Echocardiographic evaluation and surgical implications of common atrioventricular canal defects with absent or diminutive ostium primum defect.

Common atrioventricular canal defects without ostium primum defects are rare, and their accurate identification has important surgical implications. Retrospective echocardiographic database review identified subjects with common atrioventricular canal defects with absent or diminutive ostium primum defects. Surgical reports and initial and postoperative echocardiograms were reviewed to identify the imaging planes necessary to characterize this anomaly and the surgical challenges imposed by the diagnosis. Fourteen subjects were identified (93% with trisomy 21) with either absent (n = 6) or diminutive (n = 8) ostium primum defects. Malaligned conal septum was present in 50% of subjects with absent primum defects and 12.5% of subjects with diminutive defects. Immediate or long-term complications of the 11 postoperative patients included atrioventricular block (n = 4) and moderate (n = 5) or severe (n = 3) mitral regurgitation. In conclusion, echocardiographic features for the identification of common atrioventricular canal defects with absent or diminutive ostium primum defects are described. Surgical challenges involve attaining adequate exposure of the mitral component and achieving mitral valve competence.

Physiology of isolated anomalous pulmonary venous connection of a single pulmonary vein as determined by cardiac magnetic resonance imaging.

The physiology of isolated partially anomalous pulmonary venous connection of a single pulmonary vein has yet to be fully characterized. This study assessed the magnitude of the left-to-right shunt and right ventricular (RV) dilation from a single anomalous pulmonary vein using cardiac magnetic resonance imaging. Subjects with >1 anomalous pulmonary vein or associated lesions, including atrial septal defects, were excluded. In the 6 subjects identified, the median pulmonary-to-systemic flow ratio was 1.55 (range 1.3 to 1.6). The mean RV end-diastolic volume indexed to body surface area in the subjects was significantly larger than in a normal reference cohort (108 +/- 16 vs 78 +/- 18 cm(3)/m(2), p = 0.0009) and greater than the upper limit of normal in all 6 subjects. Older age did not correlate with increased magnitude of shunting (r = 0.3, p = 0.5), but increased age did correlate with RV end-diastolic volume indexed to body surface area (r = 0.96, p = 0.01). Isolated partially anomalous pulmonary venous connection with only 1 vein connecting anomalously results in a modest left-to-right shunt and mild RV dilation.

Expanding the indications for pulmonary valve replacement after repair of tetralogy of fallot.

BACKGROUND: Insertion of a competent pulmonary valve has been advocated to reduce right ventricular volume overload associated with pulmonary regurgitation (PR) after repair of tetralogy of Fallot. However the indications, proper timing, and long-term benefits of restoring pulmonary valve function remain controversial. METHODS: Thirty-six patients (aged 15.2 +/- 9.2 years) underwent pulmonary valve implantation (31 homografts, 5 heterografts) 12.2 +/- 6.9 years after tetralogy repair. Additional surgical procedures included pulmonary artery augmentation (n = 14), closure of septal defects (n = 10), and cryoablation and endocardial resection of ventricular tachycardia (n = 2). RESULTS: All patients have had clinical improvement in their exercise capacity. Preoperative and postoperative bicycle ergometry tests in 6 patients demonstrated significant improvement in the percent of predicted peak workload (68.5% +/- 19.8% to 80.7% +/- 17.4%, p < 0.015). One midterm death occurred in a 38-year-old patient with a history of ventricular tachycardia who died suddenly 2 years after pulmonary valve insertion. Postoperative echocardiographic measurements were available in 34 patients at a mean follow-up of 5 years. There was a 30% reduction in right ventricular end-diastolic diameter indexed to body surface area after surgery (30.1 +/- 10.2 to 18.6 +/- 6.0 mm/m(2), p < 0.0001). Two patients required conduit replacements at 1 and 9 years postoperatively. CONCLUSIONS: Timely insertion of a competent pulmonary valve in children, adolescents, and young adults with significant PR after tetralogy of Fallot repair results in subjective and objective improvement in exercise capacity and is associated with reduction in right ventricle size.