Interventricular septal defect shown by left ventricular cine-angiocardiography

Preoperative transcatheter closure of congenital muscular ventricular septal defects

BACKGROUND

Surgical repair of muscular ventricular septal defects, particularly those associated with complex heart lesions carries a higher risk of reoperation and death than the repair of membranous defects. Closing a muscular defect through an incision in the systemic ventricle may cause late ventricular dysfunction. In a collaborative approach to this problem, we undertook preoperative transcatheter closure of muscular ventricular septal defects remote from the atrioventricular and semilunar valves, followed by the surgical repair of associated conditions.

METHODS

In 12 patients selected jointly by a cardiologist and a cardiac surgeon, we attempted preoperative transcatheter umbrella closure of 21 defects. Half the patients had associated complex heart lesions; the others had had pulmonary-artery banding to reduce the amount of left-to-right shunting. Half had severe ventricular septal deficiency.

RESULTS

All 21 defects were successfully closed without major complications. Subsequent cardiac surgery for associated conditions in 11 of the 12 patients resulted in a mean pulmonary-to-systemic flow ratio of 1.1, indicating minimal residual left-to-right shunting; 1 patient awaited surgical repair. No deaths, reoperations, or late complications have occurred after a follow-up of 7 to 20 months.

CONCLUSIONS

A collaborative approach using transcatheter closure followed by the surgical repair of associated cardiac lesions may decrease rates of operative mortality, reoperation, and left ventricular dysfunction in patients with muscular ventricular septal defects.

Colour flow imaging in the diagnosis of multiple ventricular septal defects

Thirty one patients with multiple ventricular septal defects were studied by cross sectional echocardiography, conventional pulsed and continuous wave Doppler, colour flow imaging, and left ventriculography to determine the relative diagnostic benefits and pitfalls of each technique. The patients studied had a wide range of congenital heart defects with 19 patients having isolated multiple ventricular septal defects, three with associated tetralogy of Fallot, five with double outlet right ventricle, three with complete transposition and ventricular septal defect, and one with a complete atrioventricular septal defect. In 23 patients the defects were inspected at operation. Cross sectional imaging with integrated pulsed and continuous wave Doppler correctly identified multiple defects in only 12 (39%) patients. In contrast, colour flow imaging was accurate in 24 (77%) patients and left ventriculography in 20 (65%) patients. When patients were subdivided on the basis of relative peak systolic ventricular pressures into restrictive defects (18 patients) and non-restrictive defects (13 patients) the diagnostic value of colour flow imaging was different for each group. Colour flow mapping correctly identified multiple ventricular septal defects in 16/18 (89%) patients with restrictive defects but only 8/13 (62%) with non-restrictive defects. The comparative diagnostic accuracy of left ventriculography was 15/18 (83%) in the restrictive group and 5/13 (38%) in the non-restrictive group. Colour flow imaging was the single investigative technique with the greatest diagnostic accuracy in the diagnosis of multiple ventricular septal defects. It failed to be consistently accurate in defined subgroups with non-restrictive defects as did left ventriculography. The greatest overall diagnostic accuracy in this series was obtained when both colour flow imaging and ventriculography techniques were used in combination in a complementary fashion.

Left ventriculotomy for closure of muscular ventricular septal defects. Treatment of choice

Closure of muscular ventricular septal defects (VSDs) through the right atriotomy or right ventriculotomy may be difficult. These VSDs are often located behind the hypertrophied trabeculae carnae or papillary muscle. Residual or recurrent VSD may result from the difficult approach. Between March 1971 and December 1975, we have used the left ventriculotomy near the apex for closure of muscular VSDs in ten children. The patients' ages ranged from five months to eight years and three months. The diagnosis was established by cardiac catheterisation and left ventricular angiocardiogram in all patients. Six patients had multiple VSDs; in four patients VSD in the muscular septum was present (three apical, one midseptal). Operations were performed on cardiopulmonary bypass with moderate hypothermia and intermittent anoxic arrest. VSDs in the membranous septum were closed through the right atrium. Muscular VSDs were approached through a small vertical incision in the left ventricle near the apex. The postoperative course was uneventful in eight patients. Two patients, aged 16 months and eight years, died; histology showed grade IV pulmonary vascular disease in both. All survivors are well four months to five years after the operation, without clinical evidence of residual or recurrent VSD.