A. Tiete

Systemic right ventricular failure after atrial switch operation: midterm results of conversion into an arterial switch

BACKGROUND Failure of the systemic right ventricle after atrial switch operation can be treated by conversion into an arterial switch operation. METHODS Four patients, age 38 to 59 months, presented with right ventricular failure after Senning operation and ventricular septal defect closure. One patient had elevated left ventricular pressure; in the other three patients the left ventricle was retrained to a left ventricular/right ventricular pressure ratio of 0.8 or greater by pulmonary artery banding in 12 to 24 months. RESULTS Postoperative course after arterial switch operation was prolonged, but clinical condition was good at discharge. Fractional shortening ranged from 20% to 28%. Trace-to-moderate aortic regurgitation was present; only 1 patient had preserved sinus rhythm. After a mean follow-up of 43.5 months 1 patient had died due to left ventricular dysfunction. The survivors are in New York Heart Association functional class I to II. Fractional shortening has improved (29% to 37%); aortic regurgitation has not increased. No patient has undisturbed sinus rhythm. CONCLUSIONS Conversion of an atrial into an arterial switch is an alternative to cardiac transplantation in childhood. However, the procedure is demanding. Long-term morbidity is caused by rhythm disturbances. Aortic valve performance and left ventricular function require close observation.

Efficacy of extracorporeal membrane oxygenation in a congenital heart surgery program

SummaryBackgroundTo report our experience with extracorporeal membrane oxygenation (ECMO) in a congenital heart surgery program.MethodsSince 12/1996, 24 patients (8 newborns, 9 infants, 3 children, 4 adolescents/ adults 17–23 years), mean age 4.0±7.4 years (2 days–23 years), body weight 2.7–87 kg had ECMO as circulatory support. Indication was failure to wean from cardiopulmonary bypass in the majority of cases.ResultsMean duration of support was 3.8±2.9 d (12 h–13 d). Fourteen patients were weaned from ECMO (9 discharged), three successfully transplanted (one after switching to a pulsatile assist device). One patient on left-ventricular support required ECMO for sudden rightventricular failure (decreased). There were six deaths on ECMO due to multiorgan failure (MOV) (3) or no myocardial recovery (3). Six patients died after weaning (3 MOV, 2 myocardial failure, 1 fungal sepsis). Overall, twelve patients (50%) were discharged and are clinically well after 3.4±2.4 years (0.8–7.2 years).ConclusionIn our series, ECMO markedly reduces mortality in patients who would otherwise not survive either open heart surgery or myocardial failure of any origin and was not associated with discernible morbidity in the midterm.

Systemic mechanical heart valve replacement in children under 16 years of age

SummaryWe report the early and late outcome following left-sided mechanical heart valve replacement in children. Between 10/1981 and 02/2001, 27 children (13 male, mean age 7.2 ± 5.2 years, range 0.53–15.7 years) underwent mechanical mitral (MVR 16), aortic (AVR 9) or double valve replacement (DVR 2) with St. Jude Medical valves. Eighteen children (66.7%) had undergone previous cardiac surgery. Valve disease was congenital in 23, due to endocarditis in 2 and rheumatic in 2 patients. Concomitant cardiac surgery was performed in 12 patients (44.4%). Operative mortality was 3.7% (1/27). Perioperative complications were complete heart block (5) and myocardial infarction (1). Mean follow-up was 6.5±5.9 years (range 0.4–19 years, total 169.9 patient-years). There was one valve-related late death due to mitral valve thrombosis without phenprocoumon. Actuarial survival after 1, 5 and 10 years was 93, 93 and 93%. Late complications included endocarditis (2), minor hemorrhagic event (1) and stroke (1). Overall 10-year freedom from any anticoagulation-related adverse event under phenprocoumon was 91% (1.3%/patient year). Eight patients required reoperations: re-MVR (5; outgrowth of the prostheses (3), pannus overgrowth (2)), closure of paravalvular leak after AVR (2), and re- DVR (1; endocarditis). Actuarial freedom from reoperation after 1, 5 and 10 years was 96, 88 and 76%.ConclusionMechanical valve prostheses are a valuable option for left-sided heart valve replacement in pediatric patients with good results. Operative mortality and the incidence of any valve-related events as endocarditis, reoperation, thromboembolism or anticoagulation related bleeding is acceptable.