Left atrial isomerism: biventricular repair

Biventricular repair of hearts with left atrial isomerism often necessitates complex atrial and ventricular baffle procedures. We analysed our experience with an accent on baffle techniques.

From 1997 until 2008, 12 patients (four male) with left atrial isomerism received biventricular repair. Their median age at surgery was 9 (range: 1-24) months. Four patients had dextrocardia. Nine patients presented with left superior vena cava, three with absent right superior vena cava, five with unroofed coronary sinus and nine others with inferior vena cava interruption with (hemi)azygos continuation. Anomalous pulmonary venous drainage was present in three patients. Eight had a monoatrium. Atrioventricular septal defect (AVSD) occurred in six (complete AVSD in two), One patient with complete AVSD had right pulmonary agenesia with long segment tracheal stenosis. Multiple VSDs presented in one whereas three patients had double-outlet right ventricle (DORV) (one with borderline LV hypoplasia). Two had previous pulmonary artery banding. Complex intra-atrial baffle constructions were performed in seven patients. Complete AVSDs were corrected using two patches and all other AVSDs had one patch repair. Multiple VSDs were closed directly. DORV patients had intraventricular tunnel repair.

No early mortality occurred. Median follow-up was 54 (range: 2-134) months. One patient with complete AVSD and pulmonary agenesia died late after tracheal repair. Four patients needed five re-operations (closure of residual ASD (one), relief of left (two) or right (two) ventricular outflow obstruction, pulmonary artery branch plasty (one)). There was no atrial baffle stenosis. Four received a pacemaker. All survivors are in NYHA class I.

Survival and functional status of left isomerism patients after biventricular repair is good. Complex repairs with atrial or ventricular baffles are frequent. Arrhythmias were common and pose a concern late after repair.