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HOW MUCH CONTRAST Chamber/ vessel Normal size cc/kg Increase volume, normal flow cc/kg Marked increase... RV • Peak systolic pressure is less than 30mmHg and EDP is less than 7mmHg

CARDIAC CATHETERIZATIONS

Cao Việt Tùng MD

National Hospital of Pediatrics

Part I Basic concept

Indications

Diagnostic Intervention

Which Catheter should be used ?

pressures and to precisely localized gradients

• Side hole catheters - for angiography prevent

measurement

Type of catheter

HOW MUCH CONTRAST

Chamber/

vessel

Normal size (cc/kg)

Increase volume, normal flow (cc/kg)

Marked increase Volume & flow Aorta

1.5 2.0 1.5 1.2 2.0 1.5

1.8 2.5 2.0 1.5 2.5 2.0

Part II

Hemodynamic

Normal pressure & Saturation

RA m=3mmHg

RV: 25/3 mmHg

LA: Mean=8 mmHg

PRESSURE – VOLUME LOOP

RV

• Peak systolic pressure is less than 30mmHg and EDP

is less than 7mmHg (represents peak ‘a’ wave in right atrium)

• Increase RV pressure:

 RVOT obstruction

PA - RV

• Systolic gradient between the RV and PA :(gradient up

to 10mmHg may be normal)

• RVOT obstruction

• Gradients up to 30-40mmHg may be seen with

structurally normal PV but increase blood flow i.e

large ASD

WEDGE PRESSURE

a distal PA, good reflection of the downstream pressure i.e LA pressure, LVED

LA

 same waves as RA

 mean LA pressure is normally higher

 ‘v’ wave is higher than ‘a’ wave - caused by pulmonary vein contraction

 ‘v’ even higher when measured in PV’s

INTRACARDIAC SHUNT

• An increase saturation in between different sites in right heart suggest presence and magnitude of left to right shunt

• Decrease saturation in between different sites in left heart suggest presence and magnitude of right to left shunt

• A step up of less than 6% at atrial level, 4% at ventricular level and 4% at great vessel level – can be consider as normal

RA

• Step up of more than 9% is highly suggestive of Left

to right shunt:

– ASD with or without mitral valve disease

– Left ventricular to right atrial shunt

– VSD defect with TR

– Coronary AV fistula

– Ruptured sinus valsava into RA

RV

• Step up of more than 6% suggest of left to right shunt

– Low ASD level

– VSD defect

– Coronary AV fistula

– Ruptured sinus valsava into RV

RIGHT TO LEFT SHUNT

• Suspicious if

 the aortic saturation is <95% or

 2% or greater step between LA/LV and aorta

SHUNT CALCULATION

Flow (L/min/m2)

• Pulmonary blood flow (Qp)

• Systemic blood flow (Qs)

• assumed 98% or LA/LV/aortic if no R to L shunt

Need to get saturation for:

Aorta IVC (high and low) SVC (high and low)

PA

PV

SHUNT CALCULATION

• Normal ratio of Qp/Qs=1

• In left to right shunt, increase pulmonary blood flow the ratio increase

PVR and SVR

• O2, inhaled NO, IV or nebulized prostacyclin

• What is positive response?

– Reduction of mean PAP & PVR > 20%?

– Acute reduction of the mean PAP of > 10 mm

Hg with a resultant mean PAP of 40mmHg or less without a fall in cardiac output is

considered a positive vasoreactivity response