Improved early ventricular performance with a right ventricle to pulmonary artery conduit in stage 1 palliation for hypoplastic left heart syndrome: evidence from strain Doppler echocardiography.(Congenital Heart Disease)

Objective: To quantify non-invasively right ventricular (RV) performance in infants after stage 1 palliation for hypoplastic left heart syndrome (HLHS).

Design: Prospective, observational study with two dimensional and strain Doppler echocardiography.

Setting: Single tertiary paediatric cardiology centre.

Patients: Convenience sample of nine consecutive infants with HLHS. Four whose surgery involved a systemic to pulmonary artery (S-PA) shunt were compared with five whose surgery incorporated a right ventricle to pulmonary artery (RV-PA) conduit.

Methods: Basal RV free wall longitudinal strain rate, systolic strain ([euro]), and RV percentage area change were calculated during a single assessment between 27-50 days after surgery.

Results: Cardiopulmonary bypass time was longer in patients who underwent RV-PA (226 (30) minutes [nu] 181 (18) minutes, p = 0.03), but cross clamp time, duration of ventilation, and inotrope use did not differ. Two patients in the S-PA group died, on days 29 and 60 after surgery. Peak systolic strain rate (-1.24 (0.19)/s [nu] -0.91 (0.21)/s, p = 0.048), peak [euro] (-17.8 (1.8)% [nu] -13.4 (2.0)%, p = 0.01), and RV percentage area change (56 (6)% [nu] 25 (6)%, p < 0.01) were all greater among RV-PA patients. These indices also tended to be greater in survivors as a group. Ventricular loading conditions (oxygen saturations, diuretic treatment, and blood pressure) were similar in both groups.

Conclusion: Strain Doppler echocardiography shows improved RV longitudinal systolic contractility in patients during convalescence after the RV-PA modification of stage 1 palliation for HLHS compared with those with an S-PA shunt.

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Heart 2004;90:191-194. doi: 10.1136/hrt.2003.016675

Since Norwood described success with stage I surgical palliation (SIP) for hypoplastic left heart syndrome (HLHS), a systemic to pulmonary artery (S-PA), or Blalock-Taussig, shunt has been incorporated to provide pulmonary blood flow. (1) This surgery results in a precarious balance between systemic and pulmonary blood flow and combines the insults of significant volume loading of the right ventricle (RV) with low diastolic coronary perfusion pressure, (2) often negatively influencing the postoperative outcome.

A recently re-established modification of SIP incorporates a right ventricle to pulmonary artery (RV-PA) conduit rather than an S-PA shunt. (3) The goal of this modification is to eliminate aortic diastolic runoff into the pulmonary circulation, thus improving coronary perfusion and ventricular function. While there are limited data to suggest that hospital survival is improved for these patients, (4) it is unknown whether or not this modification results in improved performance of the RV compared with the traditional approach.

Strain Doppler echocardiography (SDE) provides a non-invasive means of quantifying myocardial deformation. (5) (6) In principle, systolic strain ([euro]) reflects the extent of myocardial fibre shortening, while strain rate (SR) reflects the velocity of myocardial shortening. The two indices provide complementary information about segmental myocardial function, are applicable to the RV, and can be measured at the bedside.

This is the first report of the …