Andersons pediatric cardiology 1497

Contrary to previous impressions, children with congenital or acquired immunodeficiencies but without identifiable risk factors for IE do not appear to be at increased risk for IE, compa

by IE185–189 in patients with or without preexisting heart condition In some of the reported cases, it may have fatal outcomes

Not confirmed in children.

Contrary to previous impressions, children with congenital or acquired

immunodeficiencies but without identifiable risk factors for IE do not appear to

be at increased risk for IE, compared with the general population.3 Furthermore, factors often associated with IE in adults, such as intravenous drug abuse and degenerative heart disease, are not common predisposing factors in younger children.21,27 Hemodialysis is a leading risk factor, especially for S aureus IE in

adults,190–193 but it seems this is not the case in children (unpublished): this might be related to the still relatively mild chronic renal failure–related ectopic valvar calcification in children

Specific Previous Procedure and Device-Related Infective

Endocarditis.

In 25% to 37% of cases, IE may develop in patients with CHD after previous cardiac operations.130,154,194

IE on Surgically Implanted RV-PA Conduits and Transcatheter

Pulmonary Implanted Valves.

There has been a substantial increase of the number of surgical RV-PA conduits and transcatheter intrastent valve implantation It has become clear that the bovine jugular vein (BJV) RV-PA conduits (Contegra, VenPro Corporation) and intrastent valves (Melody, Medtronic) have slightly higher frequency of IE as compared with homografts and porcine heterografts Although there is no

complete explanation, there has been a recent study showing increased bacterial

adhesion for S aureus on BJV valves as compared with bovine pericardial

valves.195–208

The comparison between the reported incidence of IE on transcatheter

implanted Melody valve and different types of surgically implanted RV-PA conduits is presented in a comprehensive list of studies on Table 56.11

Table 56.11

Infective Endocarditis Incidence on Transcatheter and Surgically

Reference IE Pts/Total Incidence IE (%) Follow-Up Median (Min–Max) PULMONARY TRANSCATHETER IMPLANTED BJV MELODY VALVE

Lurz et al, 2008 196 5/155 3.2 0.4 (0.2–1.9)

Cheung et al, 2013 197 6/42 14.3 2.3 (0.2–5.5)

Buber et al, 2013 198 14/147 9.5 1.6 (0.1–5.3)

McElhinney et al, 2013 199 16/311 5.1 2.5 (5.1 max)

Butera et al, 2013 200 2/63 3.2 2.5 (1.0–4.0)

Fraisse et al, 2014 201 1/64 1.6 4.6 (0.2–5.2)

Malekzadeh-Milani et al, 2014 202 5/86 5.8 1.97 (0.2–2.4)

Cheatham et al, 2015 203 14/171 8.2 4.5 (0.4–7.0)

VanDijck et al, 2015 204 8/107 7.5 2.0 (0.3–7.8)

RV-PA SURGICALLY IMPLANTED BJV CONTEGRA CONDUITS

VanDijck et al 2015 204 11/53 20.4 8.8 (0.7–13.5)

Albanesi et al, 2014 205 12/106 11.3 7.6 (1.7–12.7)

Ugaki et al, 2015 206 23/244 9.4 3.2 (0.1– 11.7)

Mery et al, 2016 207 14/245 5.7 7.0 (0.02–20)

Sandica et al, 2016 208 24/444 5.4 4.3 ± 3.8

RV-PA SURGICALLY IMPLANTED CRYOPRESERVED HOMOGRAFTS

VanDijck et al 2015 204 14/517 2.4 6.5 (0.1–23.7)

Ugaki et al, 2015 206 1/135 0.7 4.3 (0.1–11.6)

Mery et al, 2016 207 4/410 0.9 7.0 (0.02–20)

Sandica et al, 2016 208 2/267 0.7 6.6 ± 5.4

RV-PA SURGICALLY IMPLANTED DECELLULARIZED PULMONARY HOMOGRAFTS

Sarikouch et al, 2016 209 0/131 0 4.59 ± 2.76

BJV, Bovine jugular vein; IE, infective endocarditis; RV-PA, right ventricle-to-pulmonary artery.

Peculiarities of Infective Endocarditis on Transcatheter Implanted Pulmonary Valves

■ The time from implantation to IE varies: it is

possible to develop IE early (1 month) or at any point later.

■ The causal agent varies: it seems S aureus is rarer,

and oral streptococci, HACEK organisms, and

Corynebacterium spp are disproportionately

represented204; there are several reports of Bartonella

spp IE.210 – 212

■ The diagnosis cannot rely on echocardiography

alone because the positive sign of vegetations is

relatively low (up to 50%)204; intracardiac echo is

reported as a possibility,33 but it is impractical and CT

is preferred as additional imaging.

■ Acute obstruction of the valve is reported as an

important complication that may require urgent

surgery.204 , 213 , 214

■ Conservative-only management might be effective

in up to 64% However, despite the belief of a

relatively low rate of reinfection,33 a significant

proportion will eventually require surgery.

■ IE-related mortality risk varies between reports: a recent meta-analysis calculated it as 9.1%,215 which is similar to the pediatric IE as a whole.

Infective Endocarditis of Atrial Septal Defect Closure Devices.

IE may exceptionally rarely occur after ASD Amplatzer occluder device (ASO;

St Jude Medical [SJM]) implantation, related to incomplete

neoendothelialization of the device beyond the expected 6 months after the

procedure A review published in 2016216 summarized a total of six IE cases described in the literature,217–222 at 11 months to 4 years after the procedure,

mostly caused by S aureus; there are an additional two cases published.223,224 IE

is very rare considering this small number of cases for the more than 300,000 devices implanted worldwide The possibility of incomplete

neoendothelialization of the device beyond 6 months after the procedure as a predisposing factor of IE may be of importance; however, there is currently no method available to visualize this finding

Implantable Cardiac Electronic Device–Related Infective