Despitemany reports in the literature, recently pub-lished guidelines point out the fact thatconcern remains regarding the optimalstrategies for diagnosis and treatment ofcoronary artery
Trang 1DiVerent management strategies have been
suggested, including:
x discontinuation of oral anticoagulation until
normalisation of the INR without heparin
replacement;
x discontinuation of oral anticoagulation until
normalisation of the INR with heparin
replacement as soon as the INR is < 2.0;
x lowering the intensity of anticoagulation
while oral anticoagulation is maintained;
x continuing a therapeutic level of
anticoagulation
The choice of which regimen should be
followed should be based on the individual risk
for thromboembolic events, the time interval
required to be oV or at low anticoagulation
lev-els, and the risk of haemorrhage determined by
the procedure
Thus the concept of risk factor adjusted
intensity of anticoagulation can also be used to
determine the most appropriate and safest
strategy
Patient related risk factors (table 18.3)
increase thromboembolic risk by a factor of
5–20 Also prosthesis design and position have
to be taken into account Discontinuation of
anticoagulation for one week leads to a
signifi-cant thromboembolic risk in patients with
mitral valve replacement varying between
10–20%, whereas the incidence of
throm-boembolism in patients with aortic valve
replacement is 0–2%.12 w9 w14
The prothrombotic state of the surgical
pro-cedure itself may increase the risk for
thrombo-embolic events
All stages of haemostasis can be altered
dur-ing and after surgery—with increased platelet
aggregation and activation, conversion of
fibrinogen to fibrin, and depressed fibrinolysis
by decreased activators and increased
inactivators—thus potentially increasing the
thromboembolic risk of the prosthetic valve
patient The level of hypercoagulable changes
correlates with the magnitude and duration of
surgery, and postoperative changes and
com-plications such as infection The underlying
disease which first led to the surgical
procedure—such as a tumour—is a further risk
factor In a large general surgical population68% (11/16) of thromboembolic events oc-curred among patients who were operated onbecause of a tumour.12
The time interval necessary to discontinueanticoagulation before non-cardiac surgicalprocedures depends on: the half life of the oralanticoagulant used; the actual INR; the desiredINR for the specific procedure; and theindividual vitamin K pool.13
If warfarin is used, the guidelines of theAHA/ACC7and the British Society of Haema-tology1 suggest discontinuation for 72 hoursbefore routine non-cardiac surgical proce-dures The INR should be closely monitored,because the decrease in INR may vary greatlyamong diVerent patients
Dental surgery
Dental surgery is one of the procedures withthe lowest risk for thromboembolic complica-tions A recent literature review14covering 2014dental surgical procedures and 1964 extrac-tions showed that thromboembolic complica-tions occurred in five (0.9%) of 493 patients inwhom anticoagulation was discontinued How-ever, four of the five thromboembolic compli-cations were lethal In contrast, continuation ofanticoagulation in 774 patients was not associ-ated with any thromboembolic events Bleed-ing complications occurred in 1.6% patients,and none were fatal All bleedings occurredwith an INR > 4.5.14
Thus dental surgical procedures do notrequire major changes in the intensity ofanticoagulation Continuation of anticoagula-tion at an INR of 2.0–2.5 is the safest approachfor dental surgery; even full mouth extractionshave a low risk for bleeding, which can easily betreated with local measures (table 18.4).2 w15 w16
Heparin, as suggested by Peutenw17is not essary
nec-Interventional cardiac procedures
For left heart catheterisation by the brachialroute, the INR should be < 2.5, and by thefemoral route it should be < 1.8.2 w15
Surgical procedures
Minor surgical procedures can be performedwhile the INR is just < 2 and oral anticoagula-tion can be resumed on the day of surgery
Robinsonw10and Bartleyw11suggested it was notnecessary to discontinue oral anticoagulationbefore cataract extractions and other oculo-plastic surgical procedures, provided the INRwas not above the therapeutic range
Table 18.3 Risk assessment for non-cardiac surgical
patients Replace with heparin when INR: < 2.0 in average risk
patients
ANTICOAGULATION IN VALVAR HEART DISEASE
125
Trang 2Major surgical procedures require lowering
of the INR to < 1.5 In these cases
anticoagula-tion needs to be maintained with heparin
Heparin should be started when the INR is
< 2.5 in high risk patients (for example, in
patients with mitral mechanical valves) and
< 2.0 in patients with aortic mechanical valves
The activated partial thromboplastin time
(aPTT) should be prolonged to 1.5–2.0 of the
control value Heparin should be continued
until six hours before surgery and resumed
6–12 hours after surgery, when surgically
feasi-ble It should be continued until INR is > 2
Oral anticoagulation can be resumed 1–2 days
after surgery.1 2 7
Management before emergency surgery
In the event of emergency surgery, oral
antico-agulation needs to be neutralised by infusion of
prothrombin complex concentrate or fresh
fro-zen plasma, the dose of which needs to be
indi-vidualised Additional repeat small doses of
vitamin K may be given intravenously or
orally.15 16Complete reversal of oral
anticoagu-lants with vitamin K in large doses may lead to
prolonged resistance to oral anticoagulants and
the possibility of valve thrombosis and
throm-boemboli
Low molecular weight heparin
Recently it has been suggested that low
molecular weight heparin (LMWH) can be
used for the interim maintenance of
anticoagu-lation Although it is not approved for
applica-tion in patients with mechanical prosthesis, and
no studies are available for non-cardiac
proce-dures, it is already used for this purpose in
some countries Montalescot17reported the use
of LMWH in the immediate postoperative
period after valve surgery In 102 patients there
were two major bleedings and one
thrombo-embolic event, which did not diVer from the
incidence of bleeding and thromboembolic
events in a group of patients previously treated
with unfractionated heparin The study was
not randomised and was conducted for only 14
days without further follow up or
echocardio-graphic studies
If follow up is short after discontinuation of
anticoagulation, and echocardiographic studies
are not performed routinely, significant
thromboembolic events may be missed Valve
thrombosis may develop slowly and insidiously
and may not be evident for 1–2 months
No definite information on the safety and
eYcacy of LMWH is available at this time to
guide its use Because of the longer half life,
requiring only 1–2 doses per day in randomised
studies on unstable angina pectoris, LMWH
appears to have a promising role in the
perioperative management of non-cardiac
sur-gery Randomised studies, aimed at defining
doses in diVerent patient groups, are necessary
The optimal management of anticoagulation
during non-cardiac surgery requires careful
risk assessment of patients and procedures Self
testing and self management of anticoagulation
by the patient can facilitate management andreduce risks
Outlook for better anticoagulation control
Physicians and patients should become moreinformed about anticoagulation control Pa-tients need verbal and written informationabout the purpose of their anticoagulationtreatment and its eVects, the desired INR rangeand target INR, side eVects, drug interference,diet, and signs and symptoms of overdose(bleeding) and underdosing (valve thrombosisand thromboembolism), as well as other com-plications
Self monitoring of anticoagulation by tients has improved their anticoagulation con-trol5and thus their quality of life Modification
pa-of atherosclerotic risk factors is important forall patients with diseased native and prostheticheart valves to reduce thromboembolic andstroke risk
Future research should be directed towardsevaluation of alternatives to conventional anti-
Management of oral anticoagulant treatment can be improved by:
x Following the concept of risk factoradjusted indication for and intensity of oralanticoagulant treatment
x Use of the INR for monitoring the intensity
x Increasing the frequency of testing
The risks associated with interruption of oral anticoagulant treatment during non-cardiac surgery can be reduced by:
x Performing dental procedures at an INRbetween 2–2.5
x Using local measures to treat bleeding inthe dental surgery
x Replacing oral anticoagulant treatmentwith heparin before major surgery, whenINR is < 2.5 in high risk patients withmechanical mitral valves, and < 2.0 inpatients with aortic valves, up to six hoursbefore surgery
x Discontinuing warfarin 72 hours beforesurgery, but observing factors influencingthe time interval required for reduction inINR
x Resuming heparin 6–12 hours postsurgeryand maintaining until INR > 2.5
EDUCATION IN HEART
126
Trang 3coagulation in non-cardiac surgery, such asLMWH.
Methods for improved risk assessment andrisk stratification in diVerent patient groupsshould be developed, including family historyand laboratory studies for congenital oracquired risk factors for thromboembolicevents
1 British Society of Haematology British committee for
standards in haematology guidelines on oral anticoagulation, 3rd ed.Br J Haematol 1998;101:374–87.
• This is a thorough review of clinically important topics in anticoagulation and recommendations for management.
2 Gohlke-Bärwolf C, Acar J, Oakley C, et al Guidelines
for prevention of thromboembolic events in valvular heart disease Study group of the working group on valvular heart disease of the European Society of Cardiology Eur Heart J
1995;16:1320–30.
• These guidelines provide a delineation of the concept of risk factor adjusted anticoagulation in patients with various native valvar heart diseases and following all types of valve operations, and present recommendations for management in various clinical situations.
3 Acar J, Iung B, Boissel JP, et al AREVA: multicenter
randomized comparison of low-dose versus standard-dose anticoagulation in patients with mechanical prosthetic heart valves.Circulation 1996;94:2107–12.
• This was the first multicentre randomised study to compare two different target ranges of anticoagulation (INR 2–3 v 3–4) in low risk patients after aortic valve replacement with St Jude Medical valves.
4 Turpie AG, Gent M, Laupacis A, et al A comparison of
ASS with placebo in patients treated with warfarin after heart valve replacement.N Engl J Med 1993;8:524–9.
5 Bernardo A Experience with patient self-management of
oral anticoagulation.J Thromb Thrombolysis 1996;2:321–5.
6 Sawicki PT for the Working Group for the Study of Patient Self-Management of Oral Anticoagulation A
structured teaching and self-management program for patients receiving oral anticoagulation: a randomised controlled trial.JAMA 1999;281:145–50.
7 Bonow RO, Carabello B, DeLeon AC, et al ACC/AHA
guidelines for the management of patients with valvular heart disease.J Am Coll Cardiol 1998;32:1486–8.
•This is a comprehensive review of the management of valvar heart disease, setting the current standard of care.
8 Cannegieter SC, Rosendaal FR, Briët E.
Thromboembolic and bleeding complications in patients with mechanical heart valve prostheses Circulation
1994;89:635–41.
9 Butchart EG, Bodnar E, eds.Thrombosis, embolism and bleeding London: ICR Publishers, 1992: 293–317.
10 Cannegieter SC, Rosendaal F, Wintzen A, et al.
Optimal oral anticoagulant therapy in patients with mechanical heart valves.N Engl J Med 1995;333:11–17.
11 Pedersen TR Randomised trial of cholesterol lowering
in 4444 patients with coronary heart disease: the Scandinavian simvastatin survival study (4S) Lancet
1994;344:1383–9.
12 Carrel TP, Klingenmann W, Mohacsi PJ, et al.
Perioperative bleeding and thromboembolic risk during non-cardiac surgery in patients with mechanical prosthetic heart valves: an institutional review J Heart Valve Dis
1999;8:392–8.
13 White R, McKittrik T, Hutchinson R, et al Temporary
discontinuation of warfarin therapy: changes in the international normalized ratio Ann Intern Med
1995;122:40–4.
•This is a clinically important study on the time sequence of INR decrease after discontinuation of warfarin and factors that influence it.
14 Wahl MJ Dental surgery in anticoagulated patients.
Arch Intern Med 1998;158:1610–16.
•This article presents a review of studies published during the last 40 years on thromboembolic and bleeding complications associated with different anticoagulation regimens before dental surgery, showing that continuation
of anticoagulation is associated with lower thromboembolic risk without increasing bleeding significantly.
15 Shetty HGM, Backhouse G, Bentley DB, et al.
Effective reversal of warfarin-induced excessive anticoagulation with low dose vitamin K1 Thromb Haemost
1992;67:13–15.
16 Weibert RT, The Le D, Kaiser SR, et al Correction of
excessive anticoagulation with low-dose oral vitamin K1 Ann
Intern Med 1997;125:959–62.
17 Montalescot G, Polle V, Collet J, et al Low molecular
weight heparin after mechanical heart valve replacement.
Trang 4The association of coronary artery
dis-ease with heart valve disdis-ease is quently encountered and it can beexpected that this association will becomemore common because of the evolution in theepidemiology of valvar diseases Degenerativelesions are now the most frequent cause ofvalve disease in western countries and they fre-quently occur in old patients, who are also athigher risk for atherosclerotic disease Theassociation of calcified aortic stenosis and cor-onary heart disease is the main problem,because it is the most frequently encounteredassociation and because it raises specific ques-tions, particularly in regard to the detectionand management of both pathologies Despitemany reports in the literature, recently pub-lished guidelines point out the fact thatconcern remains regarding the optimalstrategies for diagnosis and treatment ofcoronary artery disease in patients with valvedisease.1
fre-Calcific aortic stenosis associated with coronary artery disease
Frequency of coronary artery disease inpatients with calcified aortic stenosis
The frequency of coronary artery disease inpatients with calcified aortic stenosis can becorrectly assessed only in studies comprisingsystematic coronary angiography, regardless ofthe symptoms The frequency of associatedcoronary disease varies according to thecharacteristics of the population involved, inparticular age and, to a lesser degree, the geo-graphic origin Series of patients with calcificaortic stenosis whose mean age is between 60and 70 years reported 30–50% of associatedsignificant coronary artery disease (at least onestenosis > 50% or 70% of vessel diameter)
Coronary artery disease has been reported inmore than 50% of patients aged > 70 years2
and, of patients aged > 80 years, in 65% inseries from the USA3 and 41% in a Britishseries.4
Series published in the 1960s and ’70s ledcertain authors to suggest that aortic stenosiscould have a protective role against coronaryatherosclerosis This was in fact probably onlythe consequence of a selection bias in series inwhich the indication of coronary angiographydepended on the symptoms Patients with aor-tic stenosis and coronary disease becamesymptomatic earlier in the course of theirdisease, which could explain the lower inci-dence and severity of coronary disease than in
patients without valve lesions More recentstudies including systematic coronary angio-graphy report frequent association of coronarydisease, with a majority of multivessel disease,and therefore do not support this hypothesis of
a protective eVect
Calcific aortic stenosis and coronary sclerosis were initially considered as twoindependent diseases, their association beinginterpreted only as a consequence of theirincreasing frequency with age Immunohisto-chemical analysis of stenotic aortic valves withdiVerent levels of severity have shown that earlylesions of aortic stenosis have several commonfeatures with atherosclerosis, in particularinflammatory cell infiltrates, lipoproteins, andcalcium deposits This is further confirmed by
athero-a prospective populathero-ation bathero-ased study, in whichpredictive factors of aortic sclerosis or stenosiswere also predictors of atherosclerosis, such asolder age, male sex, history of hypertension,smoking, and low density lipoprotein choles-terol.5The possibility that calcific aortic steno-sis and atherosclerosis could share predispos-ing factors underlines the importance ofassessing coronary status in patients with aorticstenosis
There are few data regarding the quence of coronary disease on the adaptation
conse-of the left ventricle to aortic stenosis It seemsthat patients with coronary disease have ahigher systolic wall stress because of a less pro-nounced hypertrophy, than patients with aorticstenosis and normal coronary arteries.6 Thenegative eVect of hypertrophy on left ventricu-lar function would therefore appear earlier inthe course of aortic stenosis if coronary disease
On the other hand, the negative predictivevalue of angina was thought to be high, andsome authors in the 1980s recommended notperforming coronary angiography in patientswith aortic stenosis without angina However,patients with aortic stenosis can have signifi-cant coronary artery stenosis without any chestpain Left main stenosis or three vessel diseasewas reported in 14% of the patients with aorticstenosis and no angina.7
Non-invasive assessment
Stress tests have been used to detect coronarylesions in patients with aortic valve disease, inparticular in conjunction with radionuclide
19 Interface between valve disease and
ischaemic heart disease
Bernard Iung
128
Trang 5myocardial perfusion imaging using thallium.
Such examinations generally have a rather low
specificity, because of the possibility of a false
positive result related to myocardial
hypertro-phy Moreover, sensitivity is < 100%, meaning
significant coronary artery disease can be
missed However, the main concern about the
use of stress tests on patients with aortic valve
stenosis is safety Stress tests may be performed
with specific protocols in patients with
asymp-tomatic aortic stenosis, in order to evaluate
their functional capacity accurately
Nevertheless, the presence of symptomatic
aortic stenosis remains a contraindication for a
stress test in current guidelines Tests using
dipyridamole have the same limitations
regard-ing specificity, sensitivity, and also safety Stress
echocardiography has also been shown to be
non-specific of coronary disease in patients
with aortic stenosis The detection of thoracic
aortic plaque by transoesophageal
echocardio-graphy is a strong predictor of coronary artery
disease in patients with aortic stenosis, but
10% of the patients without aortic plaque have
significant coronary artery disease Combined
assessment of carotid atherosclerosis using
echography could enhance sensitivity, although
this remains < 100% Transoesophageal
echo-cardiography can therefore not be considered
as a reliable examination to eliminate
associ-ated coronary artery disease Electron beam
computed tomography enables high grade
cor-onary artery stenosis to be detected
non-invasively High sensitivity and specificity have
been reported but this examination suVers
limitations in availability and feasibility
Coronary angiography
Given the limitations of non-invasive
tech-niques, the only method for the definite
diagnosis of coronary artery disease is coronary
angiography The risk of coronary angiography
is very low in patients with aortic stenosis when
there is no associated cardiac catheterisation
Echocardiography-Doppler generally allows an
accurate evaluation of aortic valve disease and a
haemodynamic evaluation is seldom required
North American guidelines recommend
per-forming coronary angiography in patients with
heart valve disease where there is chest pain,
objective evidence of ischaemia, decreased left
ventricular systolic function, history of
coron-ary artery disease or coroncoron-ary risk factors
(including age).1The age above which
coron-ary angiography should be systematically
performed in the preoperative evaluation of
valvar heart disease is diYcult to set definitely
North American guidelines recommend
coron-ary angiography in men over 35 years old, in
premenopausal women aged over 35 and with
coronary risk factors, and in postmenopausal
women A threshold commonly used in Europe
is 40 years for men and 50 years for women
With the current predominance of
degenera-tive valve disease, coronary angiography should
therefore be considered in nearly all patients
with calcific aortic stenosis
Treatment of aortic stenosis associated withcoronary arteriosclerosis
It is widely accepted that the treatment forsymptomatic aortic stenosis is aortic valvereplacement (AVR) Balloon dilatation pro-vides only a limited and transient improvementand does not influence the natural history ofthe disease However, concern remains asregards the optimal treatment of aortic stenosisand associated coronary artery disease accord-ing to the respective severity of both patholo-gies
Symptomatic aortic stenosis associated with significant coronary artery disease
Although the benefits are not irrevocablyproven, it is generally accepted that patientswith significant aortic stenosis associated withsignificant coronary artery disease (stenosis
> 50% or 70% of vessel diameter) should betreated by combined AVR and coronary arterybypass grafting (CABG).1 Many series havereported immediate and late results of com-bined valvar and coronary surgery in patientswith aortic and coronary disease and comparedthese results with those obtained after isolatedAVR in patients with aortic stenosis withoutcoronary lesions It is diYcult to summarise theresults of all these series, because they are het-erogenous in regard to the type of aortic valvedisease (aortic stenosis or mixed aortic stenosisand regurgitation), the severity of coronarydisease, and the period of operation (table19.1).7–12Patients treated in the 1980s and ’90swere older and had more frequent coronarydiseases.2 This evolution may explain thepersistence of a relatively high operativemortality of combined AVR and CABG,between 5–10% in most series The improve-ment of perioperative management is probablypartly counterbalanced by the increasing pro-portion of elderly patients with comorbidities
Comparative studies most often reportedhigher perioperative mortality rates after com-
Detection of coronary artery disease associated with heart valve disease
x The sensitivity of stress tests is below 100%
and they can therefore miss significantcoronary artery disease
x The main concern of stress tests is theirsafety in current practice
x Methods using imaging (transoesophagealechocardiography, electron beam
computed tomography) give promisingresults, but still have limits in feasibility andreliability
x Coronary angiography is the only currentmeans to ensure a reliable detection ofcoronary artery disease associated withheart valve disease
x Coronary angiography should besystematic in preoperative evaluation ofheart valve diseases in men aged > 40 yearsold and women > 50 years old
INTERFACE BETWEEN VALVE DISEASE AND ISCHAEMIC HEART DISEASE
129
Trang 6bined surgery than after AVR alone The
relevance of such comparisons is, however,
limited by the fact that patients with or without
coronary artery disease diVer by many
charac-teristics In particular, patients with coronary
artery disease are generally older, more
symp-tomatic, and more frequently have left
ven-tricular dysfunction We attempted to diminish
the eVect of these confounding factors in a
study comparing patients undergoing
com-bined aortic and coronary surgery with patients
having normal coronary arteries and
undergo-ing isolated AVR, who were matched for age,
sex, functional class, left ventricular ejection
fraction, and the date of operation.11 Despite
matching in some important predictive factors,
there remained a trend towards a higher
opera-tive mortality (10.4% v 4.9%, p = 0.08) in
patients undergoing combined aortic and
coronary surgery In multivariate analysis
taking into account other patient
characteris-tics, combined CABG is associated with a
lower increase in operative mortality than in
univariate analysis.2 These findings do not
indicate that CABG in itself increases the risk
of AVR, but should be interpreted as the
adverse influence of an associated
atheroscle-rotic disease on the result of cardiac surgery
Long term results after AVR associated with
CABG are generally good, with survival rates
> 60% at nine and 10 years in recent studies,
despite the high risk profile of the patients
(table 19.1).10 11The comparison of late results
after isolated AVR in patients with normal
cor-onary arteries reveals the same limitations as
the comparison of early mortality, because of
the diVerences in the patients involved In
matched populations, mortality was not
signifi-cantly higher in patients undergoing combined
surgery up to nine years after the postoperative
period.11 Relative survival, compared with a
standard population, was not influenced by
CABG until 10 years after surgery in another
series.2 Apart from survival, late functional
results are excellent in most series, most
patients being in New York Heart Association
(NYHA) class I–II, without a low incidence of
angina and acute coronary events.9–11
Despite a trend towards an increase in
peri-operative mortality compared with patients
with normal coronary arteries, the immediate
results of AVR associated with CABG are
satisfying according to the characteristics of the
patients involved These results support the
current practice which is to bypass significant
coronary artery stenosis (50% for left main and
50–70% for other arteries) when possible in
patients who should have AVR for aortic valvestenosis (figs 19.1 and 19.2).1The extrapola-tion of large series on CABG suggests that theuse of the left internal mammary artery should
be recommended for the grafting of the leftanterior descending artery in those patientsmore frequently operated on at an advancedage, and for whom late reoperation should beavoided
Isolated AVR in patients with coronary artery stenosis
Published series comprise only a few patientswho had coronary stenosis associated with aor-tic stenosis and who underwent isolated AVRwithout CABG Moreover, these patients con-stitute a particularly heterogeneous group,because the absence of CABG can be related tovery diVerent situations, whether it is deliberate
in moderate stenosis (approximately 50%) orimpossible in significant stenosis because ofanatomical conditions The absence of CABGwas deliberate in all cases only in the Bonowseries,13 which reported a favourable outcome
Table 19.1 Results of aortic valve replacement combined with coronary artery bypass grafting in patients with aortic valve disease associated with coronary artery disease
Series Years of operation AVR+ CABG (n) AS (n) Mean age (years) 3 vessel or LM (%) Operative deaths (%) Late survival (%)
*Among postoperative survivors.
AVR, aortic valve replacement; AS, aortic stenosis; CABG, coronary artery bypass grafting, LM, left main stenosis.
Figure 19.1 Calcified aortic stenosis associated with
a 50% distal left main stem stenosis.
Figure 19.2 Calcified aortic stenosis with a tight
stenosis on the second segment of a diffusely atherosclerotic right coronary artery.
EDUCATION IN HEART
130
Trang 7but whose interpretation should take into
account the majority of mono-vessel diseases
and the short follow up In our experience, mid
term outcome after isolated AVR in patients
who had aortic stenosis associated with
moder-ate coronary artery stenosis (40–60%) is
excel-lent and identical to patients with normal
cor-onary arteries (fig 19.3).11As regards patients
who had aortic stenosis and significant
coron-ary disease which could not be bypassed for
technical reasons, there was a trend towards a
higher postoperative mortality and a more
rapid decrease of the survival curve after a four
year follow up.7 10 11 However, mid term
sur-vival was satisfying (60% at five years) and
functional results were good, with more than
90% of the patients being free from angina in
the absence of CABG.11 It is necessary to be
cautious given the small number of patients,
but these results strongly suggest that AVR
should be performed in patients with
sympto-matic aortic stenosis, even if they have
significant coronary lesions which cannot be
bypassed for technical reasons Immediate and
late results seem less satisfying than those in
patients who underwent combined aortic and
coronary surgery but are far better than the
natural history of aortic stenosis Future
studies are needed to evaluate the association
of transmyocardial laser revascularisation with
AVR in such patients
Moderate aortic stenosis associated with
significant coronary artery disease
In patients who have moderate aortic stenosis
and significant coronary artery disease for
which there is an indication for
revascularisa-tion, percutaneous coronary angioplasty
should be considered if possible In patients
who have coronary artery disease requiring
CABG, the therapeutic choice is between :
x associating AVR and CABG, which is a
radical treatment but exposes the patient to
a higher operative risk and, later, to
prosthetic related complications;
x performing only CABG, which will expose
the patient to a subsequent AVR in case of
progression of the aortic stenosis
The mean rate of progression of aortic stenosis
has been estimated at between 5–8 mm Hg per
year for mean gradient, with a mean declinebetween 0.1–0.2 cm2 per year in valve area.14
However, it is very diYcult to predict the gression of aortic stenosis in any given patient
pro-Valve replacement in a patient who haspreviously undergone CABG can be techni-cally complex and associated with an increasedmortality.15The possible evolution of moderateaortic stenosis and the risk of subsequentsurgery leads to AVR, associated with CABG,being recommended in patients who havemoderate aortic stenosis associated with coron-ary lesions requiring surgery Valve replace-ment should be performed if valve area is below
1 cm2 and considered if between 1–1.5 cm2,and/or if mean aortic gradient is between30–50 mm Hg.1
Choice of prosthesis
The major determinant of the choice between amechanical prosthesis and a bioprosthesis isthe comparison between the presumed lifeexpectancy of the patient and the duration ofthe prosthesis Bioprostheses are clearly recom-mended for patients over 80 years old, whilemechanical prostheses are generally preferred
in patients aged < 70 years The choice may bediYcult between 70 and 80 years Coronarydisease is frequently associated in this agegroup and can be considered as a promotingfactor for a mechanical prosthesis, though thispoint is controversial.16 Patients undergoingcombined aortic and coronary surgery mayhave a life expectancy that will expose them toprimary degeneration of the bioprosthesis Therisk of reoperation, which is still high in theelderly, is even more increased in patients whohave previously undergone combined aorticand coronary surgery
Medical treatment after combined aortic and coronary surgery
Patients who have undergone AVR with amechanical prosthesis can benefit from moder-ate anticoagulation (target international nor-malised ratio 2–3), provided their thrombo-embolic risk is low—that is, patients in sinusrhythm, without previous embolism and with
no severe enlargement of the left atrium.17
Moderate anticoagulation ensures an eYcientprotection against embolic events at a lowerhaemorrhagic risk This point is particularlyimportant after combined aortic and coronarysurgery because patients should also be treatedwith aspirin The combination of anticoagu-lants and aspirin is not recommended in allpatients with prosthetic heart valves, but its use
is supported by the results of clinical trials inpatients who have mechanical heart valvesassociated with atherosclerotic disease
Patients with CABG particularly benefitfrom treatment with statins It is logical to con-sider prescribing a statin in most, if not all,patients who have undergone combined aorticand coronary surgery The choice of the type ofstatin must take into account the possibility ofdrug interaction with oral anticoagulant treat-ment
Figure 19.3 Calcified aortic stenosis with
atherosclerosis of left anterior descending and
circumflex arteries, no stenosis being more than
50%.
INTERFACE BETWEEN VALVE DISEASE AND ISCHAEMIC HEART DISEASE
131
Trang 8Coronary artery disease associated
with other valve diseases
Aortic regurgitation
Left ventricular ejection fraction is clearly an
important parameter to be taken into account
in the decision to operate on a patient with
severe aortic regurgitation, particularly in the
absence of symptoms In the case of significant
coronary artery disease, the respective roles of
aortic regurgitation and coronary disease in
ventricular dysfunction can be debated
How-ever, there are no grounds for using diVerent
thresholds in patients with or without coronary
artery disease
Just as in other valve diseases, degenerative
lesions are a growing cause of aortic
regurgita-tion Degenerative aortic regurgitation may be
associated with an aneurysm of the ascending
aorta, thereby requiring not only valve
replace-ment but a composite replacereplace-ment with an
aortic tube and a prosthesis associated with
reimplantation of the coronary arteries If the
patient also requires CABG, mammary artery
grafts should be used if possible to avoid the
anastomosis of the grafts on the pathological
ascending thoracic aorta
Mitral stenosis
The frequency of coronary artery disease is low
among patients with mitral stenosis because
this rheumatic disease is predominantly found
in young patients In older patients the
diagno-sis and therapeutic management of coronary
artery disease does not diVer from other valve
diseases Angina pectoris can occur in patients
with mitral stenosis and normal coronary
arteries, and it could be related to ischaemia of
the right ventricle The only other unique
fea-ture of coronary disease in patients with mitral
stenosis is the possibility of coronary
embo-lism
Mitral regurgitation
The association of mitral regurgitation and
coronary artery disease diVers from the
associ-ation of other valve diseases with coronaryatherosclerosis As in other cases, this can bethe conjunction of two diVerent pathologies,but also a unique pathology, coronary arterydisease being the only cause in the case ofischaemic mitral regurgitation
Coronary artery disease associated with non-ischaemic mitral regurgitation
On this topic there are less data in theliterature, compared with the association ofaortic valve and coronary diseases, and mostseries concern mitral valve replacement associ-ated with CABG Combined valvar and coron-ary surgery is associated with a trend towards ahigher perioperative mortality, but patientswith associated coronary artery disease are also
at higher risk than patients with isolated mitralvalve disease and normal coronary arteries.18 19
However, with the evolution of the ology of heart valve disease and the improve-ment in techniques of valve repair, combinedsurgery performed in patients with mitralregurgitation in western countries most fre-quently associates mitral valve repair andCABG The advantages of valve repair overvalve replacement—that is, lower perioperativemortality and improved event-free lateoutcome—should be taken into account whenassociating valve repair with CABG, particu-larly in patients who have a preoperativeimpairment of left ventricular function Theadvantages of an early operation in patientswith severe mitral regurgitation are even morepronounced in patients who have concomitantcoronary artery disease.20 The association ofcoronary lesions with severe mitral regurgita-tion should therefore be an incentive toconsider an early valve repair
epidemi-Ischaemic mitral regurgitation
Tackling the subject of mitral regurgitation indepth is beyond the scope of this paper,because it should not be considered as aninterface between valvar and coronary disease,but only as an ischaemic disease
Acute ischaemic mitral regurgitation iscaused by rupture of the papillary muscleoccurring at the acute phase of myocardial inf-arction, generally with an inferior location.Despite the high risk, urgent surgery is manda-tory because of the catastrophic prognosis.Most problems in managing ischaemicmitral regurgitation are encountered in pa-tients with chronic ischaemic mitral regurgita-tion Such patients have normal leaflets and theregurgitation is caused by modifications of thegeometry and kinetics of the subvalvar appara-tus, as a consequence of the abnormalities oflocal myocardial contraction Quantification ofthe regurgitation may be diYcult, particularlybecause of the possibility of variations in thegrade of mitral regurgitation according to theischaemia
There is a consensus for performing bined mitral and coronary surgery in the case
com-of severe ischaemic mitral regurgitation (grade
3 or 4), although the operative risk is generallyhigher than in the case of non-ischaemic mitralregurgitation associated with coronary disease
Combined aortic valve replacement and
coronary artery bypass grafting (CABG)
x CABG should be conducted in association
with aortic valve replacement, when
possible, for all coronary arteries with
significant stenosis
x In patients who have significant,
non-bypassable coronary artery stenosis,
aortic valve replacement, if otherwise
indicated, should not be contraindicated on
the basis of coronary status
x The progression of aortic stenosis and the
problems related to valve replacement after
previous coronary surgery support wide
indications for aortic valve replacement in
patients who have moderate aortic stenosis
and in whom CABG is indicated
EDUCATION IN HEART
132
Trang 9Valve repair gives good immediate and midterm results in such patients, but we only have
a few series with limited follow up
The treatment of moderate ischaemic mitralregurgitation (grade 2) is a matter of debate
Moderate regurgitation is traditionally not rected at the time of CABG However, asubgroup analysis of the SAVE (survival andventricular enlargement) study suggests thatmoderate mitral regurgitation has a negativeprognostic value on the outcome of patientsfollowing myocardial infarction Whether thecorrection of moderate ischaemic mitral regur-gitation by valve repair will improve theoutcome of such patients remains to be deter-mined by further studies
cor-1 ACC/AHA Guidelines for the Management of Patients with Valvular Heart Disease A report of the American
College of Cardiology/American Heart Association task force
on practice guidelines.J Am Coll Cardiol 1998;32:1486–88.
• These recent guidelines summarise most aspects of the management of valvar diseases, in particular as regards paraclinic assessment and indications for surgery.
Recommendations are given regarding indications for coronary angiography in patients with valvar disease and for aortic valve replacement in patients undergoing coronary surgery.
2 Kvidal P, Bergström R, Hörte LG, et al Observed and
relative survival after aortic valve replacement J Am Coll
Cardiol 2000;35:747–56.
• This large series with a long term follow up is particularly interesting owing to its analysis not only of absolute survival, but also relative survival as compared with a standard population This provides useful information on predictive factors of late results of aortic valve replacement, in particular in patients aged over 70 years.
3 Akins CW, Daggett WM, Vlahakes GJ, et al Cardiac
operations in patients 80 years old and older Ann Thorac
Surg 1997;64:606–15.
4 Gilbert T, Orr W, Banning AP Surgery for aortic stenosis
in severely symptomatic patients older than 80 years:
experience in a single UK centre.Heart 1999;82:138–42.
5 Stewart BF, Siscovick D, Lind BK, et al Clinical factors
associated with calcific aortic valve disease Cardiovascular health study.J Am Coll Cardiol 1997;29:630–4.
• A large population based study which enables the frequency of different degrees of aortic stenosis to be assessed The analysis of predictive factors suggests the possibility of common factors in the pathogenesis of atherosclerosis and degenerative aortic stenosis.
6 Lund O, Flo C, Jensen FT, et al Left ventricular systolic
and diastolic function in aortic stenosis Prognostic value after valve replacement and underlying mechanisms Eur
Heart J 1997;18:1977–87.
7 Mullany CJ, Elveback LR, Frye RL, et al Coronary
artery disease and its management: influence on survival in
patients undergoing aortic valve replacement J Am Coll
Cardiol 1987;10: 66–72.
•A comparative study of patients undergoing isolated aortic valve replacement with or without coronary disease and patients undergoing combined aortic and coronary surgery over two time periods The results support a wide use of preoperative coronary angiography and the association of bypass grafting with aortic valve replacement.
8 Lytle BW, Cosgrove DM, Gill CC Aortic valve
replacement combined with myocardial revascularization J
Thorac Cardiovasc Surg 1988;95:402–14.
•A study of 500 patients treated by combined aortic valve replacement and coronary surgery, with a 10 year follow
up and an analysis of the predictive factors of late results.
9 Czer LS, Gray RJ, Stewart ME, et al Reduction in
sudden late death by concomitant revascularization with aortic valve replacement J Thorac Cardiovasc Surg
1988;95:390–401.
•This comparative study comprises 474 patients operated
on for aortic valve replacement with or without bypass grafting Despite differences in patient characteristics, long term results (up to 12 years) suggest a benefit of associating coronary and aortic surgery.
10 Lund O, Nielsen TT, Pilegaard HK, et al The influence
of coronary artery disease and bypass grafting on early and late survival after valve replacement for aortic stenosis J
Thorac Cardiovasc Surg 1990;100:327–37.
11 Iung B, Drissi MF, Michel PL, et al Prognosis of valve
replacement for aortic stenosis with or without coexisting coronary heart disease: a comparative study J Heart Valve
Dis 1993;2:259–266.
•This study compared 144 patients treated by combined aortic and coronary surgery with 144 other patients operated on for aortic stenosis with normal coronary arteries, and who were matched for the main predictors of immediate and late results There is a trend toward a higher operative mortality but not towards late death in the patients who had combined surgery.
12 Flameng WJ, Herijgers P, Szecsi J, et al Determinants
of early and late results of combined valve operations and coronary artery bypass grafting Ann Thorac Surg
1996;61:621–8.
13 Bonow RO, Kent KM, Rosing D, et al Aortic valve
replacement without myocardial revascularization in patients with combined aortic valvular and coronary artery disease.
Circulation 1981;63:243–51.
•This comparative study reports good results of isolated aortic valve replacement in patients with aortic stenosis and coronary artery disease However, the low severity of coronary lesions (18% of three vessel disease) and the follow up of only four years limit the relevance of the findings.
14 Brener SJ, Duffy CI, Thomas JD, et al Progression of
aortic stenosis in 394 patients: relation to changes in myocardial and mitral valve dysfunction J Am Coll Cardiol
1995,25:305–10.
15 Odell JA, Mullany CJ, Schaff HV, et al Aortic valve
replacement after previous coronary artery bypass grafting.
Ann Thorac Surg 1996;62:1424–30.
•This series includes 145 patients operated on for aortic valve replacement after a previous coronary bypass grafting It shows an increased operative morbidity and mortality, and generally recommends valve replacement in patients with moderate aortic stenosis who need coronary surgery.
16 Jones EL, Weintraub WS, Craver JM, et al Interaction
of age and coronary disease after valve replacement:
implications for valve selection Ann Thorac Surg
1994;58:378–85.
17 Acar J, Iung B, Boissel JP, et al AREVA: multicenter
randomized comparison of low-dose vs standard dose anticoagulation in patients with mechanical prosthetic heart valves.Circulation 1996;94:2107–12.
•This prospective, randomised trial concludes that there is a benefit from using moderate anticoagulation in selected patients after aortic valve replacement with a mechanical prosthesis This is associated with a lower rate of bleeding without increasing the thromboembolic risk.
18 Lytle BW, Cosgrove DM, Gill CC, et al Mitral valve
replacement combined with myocardial revascularization:
early and late results for 300 patients, 1970 to 1983.
Circulation 1985;71:1179–90.
19 He GW, Hughes CF, McCaughan B, et al Mitral valve
replacement combined with coronary artery operation:
determinants of early and late results Ann Thorac Surg
1991;51:916–23.
20 Triboulloy C, Enriquez-Sarano M, Schaff HV, et al.
Impact of preoperative symptoms on survival after surgical correction of organic mitral regurgitation Rationale for optimizing surgical indications.Circulation 1999;99:400–5.
Mitral regurgitation associated with coronary artery disease
x The mechanism of mitral regurgitationshould be carefully assessed in thepreoperative evaluation:
– to diVerentiate ischaemic mitralregurgitation from non-ischaemicregurgitation associated with coronarydisease;
– to evaluate the possibility of valverepair
x Valve repair should be consideredearly—that is, in NYHA class I or II—inpatients who have severe mitral
regurgitation associated with coronaryartery disease
Trang 10The aortic valve, and its supporting
ven-tricular structures, form the piece of the heart All chambers of theheart are related directly to the valve, and itsleaflets are incorporated directly into thecardiac skeleton As such, the valve is the focusfor the echocardiographer Yet still the precisestructure of its component parts remainscontroversial, with persisting disagreementsrelating largely to the enigmatic “annulus”
centre-Indeed, it is diYcult to find an unequivocaldefinition of the annulus, a structure appearingmost frequently in the context of cardiacsurgery.1
This review describes the arrangement of theaortic root in terms of the attachment of theaortic valvar leaflets, and their relations to theaorta and its ventricular support.2Recognisingthat these parts will still be considered torepresent an annulus, I will try to show that thering like structure thus described has consider-able length, encompassing the entirety of thesemilunar attachments of the leaflets It is therecognition of the relation of these attachments
to the anatomic and haemodynamicventriculo-arterial junctions which is the key tounderstanding.3
Location of the aortic root
Although forming the outlet from the left tricle, when viewed in the context of the heart
ven-as it lies within the chest (“attitudinally correctorientation”4), the aortic root is positioned tothe right and posterior relative to the subpul-monary infundibulum (fig 20.1) The subpul-monary infundibulum is a complete muscularfunnel which supports in uniform fashion theleaflets of the pulmonary valve.5In contrast, theleaflets of the aortic valve are attached only inpart to the muscular walls of the left ventricle.This is because the aortic and mitral valvar ori-fices are fitted alongside each other within thecircular short axis profile of the left ventricle, ascompared to the tricuspid and pulmonaryvalves which occupy opposite ends of thebanana shaped right ventricle (fig 20.2) Whenthe posterior margins of the aortic root areexamined, then the valvar leaflets are seen to bewedged between the orifices of the two atrio-ventricular valves (fig 20.3) Sections in longaxis of the left ventricle then reveal the fullextent of the root, which is from the proximalattachment of the valvar leaflets within the leftventricle to their distal attachments at thejunction between the sinusal and tubular parts
of the aorta (fig 20.4)
How can we describe the aortic root?
Forming the outflow tract from the left cle, the aortic root functions as the supportingstructure for the aortic valve As such, it forms
ventri-a bridge between the left ventricle ventri-and theascending aorta The anatomic boundarybetween the left ventricle and the aorta,however, is found at the point where the
20 Clinical anatomy of the aortic root
Robert H Anderson
Figure 20.2 The ventricular apexes have been amputated from this ventricular
mass, and the base of the heart is shown from beneath in left anterior oblique
orientation Note the central location of the aortic valve, which is overlapped by
the mitral valve within the short axis of the left ventricle The tricuspid and
pulmonary valves are separated by the supraventricular crest in the roof of the
right ventricle The dotted line shows the area of fibrous continuity between the
leaflets of the aortic and mitral valves.
Figure 20.1 In this normal human heart, viewed in
attitudinally correct orientation, the subpulmonary infundibulum has been transected, and the pulmonary valve removed, showing the central position of the aortic root within the cardiac short axis.
134
Trang 11ventricular structures change to the fibroelasticwall of the arterial trunk This locus is notcoincident with the attachment of the leaflets ofthe aortic valve As shown in fig 20.4, the leaf-lets are attached within a cylinder extending tothe sinutubular junction of the aorta Thesemilunar attachments of the leaflets them-selves form the haemodynamic junction be-tween left ventricle and aorta All structuresdistal to these attachments are subject to arte-rial pressures, whereas all parts proximal to theattachments are subjected to ventricular pres-sures.
Opening out the aortic root shows the plexities of these relations (fig 20.5) Thestructures distal to the semilunar attachmentsare the valvar sinuses, into which the semilunarleaflets themselves open during ventricular sys-tole Two of these valvar sinuses give rise to thecoronary arteries, usually at or below the level
com-of the sinutubular junction (figs 20.3 and20.4) The arrangement of the coronary arter-ies permits these two sinuses to be called theright and left coronary aortic sinuses Whentheir structure is examined, it can then be seenthat, for the greater part, the sinuses are made
up of the wall of the aorta At the base of each
of these coronary sinuses, however, a crescent
of ventricular musculature is incorporated aspart of the arterial segment (fig 20.6) Thisdoes not happen within the third, non-coronary, sinus This is because the base of thissinus is exclusively fibrous in consequence ofthe continuity between the leaflets of the aorticand mitral valves (fig 20.5)
Examination of the area of the root proximal
to the attachment of the valvar leaflets alsoreveals unexpected findings Because of thesemilunar nature of the attachments, there arethree triangular extensions of the left ventricu-lar outflow tract which reach to the level of thesinutubular junction These extensions, how-ever, are bounded not by ventricular muscula-ture, but by the thinned fibrous walls of theaorta between the expanded sinuses Each ofthese triangular extensions places the most dis-tal parts of the left ventricle in potentialcommunication with the pericardial space or,
in the case of the triangle between the two onary aortic valvar sinuses, with the tissueplane between the back of the subpulmonaryinfundibulum and the front of the aorta (fig20.4) The triangle between the left coronaryand the non-coronary aortic valvar sinusesforms part of the aortic-mitral valvar curtain,with the apex of the triangle bounding thetransverse pericardial sinus (fig 20.4) The tri-angle between the non-coronary and the rightcoronary aortic valvar sinuses incorporateswithin it the membranous part of the septum
cor-This fibrous part of the septum is crossed on itsright side by the hinge of the tricuspid valve,which divides the septum into atrioventricularand interventricular components The apex ofthe triangle, however, continuous with theatrioventricular part of the septum, separatesthe left ventricular outflow tract from the rightside of the transverse pericardial sinus, extend-ing above the attachment of the supraventricu-lar crest of the right ventricle
Figure 20.3 The short axis of the heart is
photographed from above and from the right,
producing a right posterior oblique orientation Note
that the aortic root is deeply wedged between the
orifices of the mitral and tricuspid valves Note also
the origins of the coronary arteries from the sinuses
of the aortic valve adjacent to the pulmonary trunk.
Figure 20.4 This is a close up of the aortic root,
having sectioned the left ventricle along its own long
axis Note the length of the root between the basal
attachments of the valvar leaflets and the sinutubular
junction Note also the thin areas of aortic wall which
separate the left ventricular cavity from the
pericardial space just below the level of the
sinutubular junction.
CLINICAL ANATOMY OF THE AORTIC ROOT
135
Trang 12When considered as a whole, therefore, the
aortic root is divided by the semilunar
attachment of the leaflets into supravalvar and
subvalvar components.1The supravalvar
com-ponents, in essence, are the aortic sinuses, but
they contain at their base structures of
ventricular origin The supporting subvalvar
parts are primarily ventricular, but extend as
three triangles to the level of the sinutubular
junction Stenosis at the level of the
sinutubu-lar junction is usually described as being
“sup-ravalvar” In that the peripheral attachments of
the leaflets are found at this level, the junction
is also an integral part of the valvar
mech-anism.6 Indeed, stretching of the sinutubular
junction is one of the cardinal causes of valvar
incompetence
Does the aortic valve have an
annulus?
As with so many disputes, the answer to this
ongoing conundrum resides in the definition of
an “annulus” In the strictest sense, an annulus
is no more than a ring In this respect, the
entirety of the aortic root can be removed from
the heart, and slipped on the finger in the form
of a ring Within the ring as thus removed,
how-ever, the leaflets themselves are not supported
in ring-like, but rather in crown-like fashion
The answer regarding the presence or absence
of an annulus, therefore, is very much in the
eyes of the beholder Some have argued that
fibrous thickenings attach the leaflets within the
root, and point to these supposed thickenings as
the “annulus”.1I find this confusing, since the
purported thickenings are not universally
present Even when found, if removed they
would constitute a crown-like circlet rather than
a true ring It is my own belief that the aortic
root would be best understood if divorced from
the concept of the “annulus” This is unlikely to
happen SuYce it to say, therefore, that the
“ring” takes the form of the cylindrical aortic
root in which the valvar leaflets are supported in
crown-like fashion (fig 20.7)
Clinical implications
There are several inferences from the complex
interplay of ventricular and arterial structures
which make up the aortic root which are
important in the clinical context When seen in
long axis section, the diameter of the root varies
greatly through its short length The root is
much wider at the midpoint of the sinuses than
at either the sinutubular junction or at the basal
attachment of the leaflets This becomes of
sig-nificance when considering measurements of
the “annulus” since, as discussed, the hinges of
the leaflets extend through all these three
levels Proper values can only be provided when
measurements are made at the bottom of the
valvar attachments, at the widest point of the
sinuses, and at the sinutubular junction
Similarly, if measurements were taken from the
basal attachment of one leaflet to the
compara-ble point of an adjacent leaflet, as is frequentlyshown in diagrams, this would not measure thefull diameter of the outflow tract, but rather atangent across the root These considerationsare also important in a surgical context Thenative valvar leaflets are obviously removedduring the procedure of valvar replacement
The prostheses used for the purposes ofreplacement most usually have a truly circularsewing ring Should the stitches used for secur-ing this ring be placed within the semilunarremnants of the removed valvar leaflets, thenthere will be some distortion when the valve is
Figure 20.5 The aortic root has been opened through a longitudinal incision
across the area of aortic-mitral valvar continuity, and spread open to show the semilunar attachments of the valvar leaflets Note the interleaflet triangles extending to the sinutubular junction, and the crescents of myocardium at the base of the two coronary aortic sinuses.
Figure 20.6 This section across one of the two
coronary sinuses of the aortic valve shows how the hinge of the valvar leaflet is attached to the ventricular myocardium well proximal to the anatomic ventriculo-arterial junction (see fig 5 also).
EDUCATION IN HEART
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Trang 13“seated”, albeit that this does not usually promise its subsequent function Whennecropsied hearts are examined subsequent tovalvar replacement, the circular sewing ring isusually found to be located at the anatomicventriculo-arterial junction.2 It is the normaldiscrepancy between this junction and thehaemodynamic junction which is the key tounderstanding the clinical anatomy of the aor-tic root.
com-I am indebted to Dr Siew Yen Ho for her help in the preparation
of this review, and to Karen McCarthy and Vi Hue Tran for help
in preparing the illustrations The work itself was supported by the British Heart Foundation together with the Joseph Levy Foundation.
1 Yacoub MH, Kilner PJ, Birks EJ, et al The aortic
outflow tract and root: a tale of dynamism and crosstalk Ann
Thorac Surg 1999;68(suppl):S37–43.
•A review of a lifetime’s experience of surgery to the aortic root Like many surgeons, however, Sir Magdi views the aortic valvar leaflets as though supported by an “annulus”.
Included in the review is a picture demonstrating the so-called “annulus”, but this is taken at a single level across the semilunar hinge line of the leaflet No consideration is given to the length of the root, nor the semilunar arrangement of the leaflets Sir Magdi’s picture should be compared with fig 6 as shown in this review.
2 Sutton JPIII, Ho SY, Anderson RH The forgotten
interleaflet triangles: a review of the surgical anatomy of the aortic valve.Ann Thorac Surg 1995;59: 419–27.
•An alternative account of the surgical anatomy of the aortic valve, taking cognisance of the semilunar arrangement of the leaflets, and the interdigitations thus produced between the aortic valvar sinuses and the fibrous extensions of the suboartic outflow tract.
3 Anderson RH Editorial note: the anatomy of arterial
valvar stenosis.Int J Cardiol 1990;26:355–60.
•A short note which emphasised the discrepancy between the anatomic and haemodynamic ventriculo-arterial junctions It is appreciation of this discrepancy which is the key to understanding of the clinical anatomy.
4 McAlpine WA.Heart and coronary arteries An anatomical atlas for clinical diagnosis, radiological investigation, and surgical treatment Berlin: Springer-Verlag, 1995.
•This atlas was produced long before it was ready to be appreciated The work is a true thing of beauty, and the gems to be found within its pages are manifold It is not easy to understand, but the effort needed to extract the salient clinical material is well worth it.
5 Stamm C, Anderson RH, Ho SY Clinical anatomy of the
normal pulmonary root compared with that in isolated pulmonary valvular stenosis J Am Coll Cardiol
1998;31:1420–5.
•An analysis of the normal pulmonary valve is used as the foundation for understanding the malformations which produce valvar stenosis The key, once more, is to appreciate the semilunar arrangement of the leaflets The essence of valvar stenosis is progressive fusion of the zones of apposition between the valvar leaflets.
6 Stamm C, Li J, Ho SY, et al The aortic root in
supravalvular stenosis: the potential surgical relevance of morphologic findings J Thorac Cardiovasc Surg
1997;114:16–24.
•This analysis is concerned with so-called “supravalvar”
stenosis As is shown, the level of narrowing in this entity
is almost always found at the sinutubular junction, and involves additionally the valvar leaflets.
Figure 20.7 A diagrammatic representation of the aortic root shows its
considerable length The leaflets are attached within the cylinder of the root in the
form of a coronet.
CLINICAL ANATOMY OF THE AORTIC ROOT
137