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.

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 (epsilon), 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 v 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 v -0.91 (0.21)/s, p = 0.048), peak epsilon (-17.8 (1.8)% v -13.4 (2.0)%, p = 0.01), and RV percentage area change (56 (6)% v 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.