Right ventricular unloading for heart failure related to Ebstein malformation

Abstract

Background: Patients with Ebstein malformation (EM) and severe RV dilatation and dysfunction have increased operative risk. Early results with right ventricular unloading utilizing the bidirectional cavopulmonary shunt (BCPS) during repair of EM have been encouraging. We report our experience of the 1.5-ventricle repair strategy for this difficult group of patients.

Methods: Between July 1999 and January 2013, 62 patients with severe EM underwent BCPS at the time of tricuspid repair. Median age was 21.5 years (range, 9 months to 57 years), 51.6% were male, and 72.5% were children. Severe RV dilatation was present in all patients; severe RV dysfunction was present in 72.5% (n=45) and moderate to severe RV dysfunction in 22.5% (n=14). Mean RV systolic pressure was 32.7±0.7 mm Hg and mean PA pressure was 15.6±2.1 mm Hg. Mean preoperative left ventricular ejection fraction (LVEF) was 0.536±0.071; it was less than 40% in 10 patients (16.1%). New York Heart Association class III/IV heart failure was present in 43 patients (69.3%) preoperatively and 20 patients (32.2%) were initially referred for heart transplant evaluation. Prior EM surgery occurred in 35.4% (n=22; 8 prior valve repair, 8 prior valve replacement, Blalock-Taussig shunt in 4, atrial septal defect (ASD) closure in 2).

Results: Tricuspid repair was performed in 51.6% (n=32, 5 had re-repair). Bioprosthetic valve replacement was performed in 48.4% (n=30, 8 had rereplacement). The BCPS was a planned procedure in 53 patients (85.5%) because of RV dysfunction; BCPS was added after unsuccessful weaning from bypass in 7 (11.2%), and in the early postoperative period due to hemodynamic instability in 2. Concomitant procedures included ASD closure in 48.3%, maze in 38.7%, and mitral valve repair in 6.4%. Postoperative extracorporeal membrane oxygenation support was needed in 8 patients. Delayed chest closure was performed in 25.8%. Early mortality was 1.6% (n=1). Mean mechanical ventilation time was 69.7 hours. Mean intensive care unit and hospital stays were 5.4±3.5 and 10.7±3.5 days, respectively. Mean follow-up was 3.6±2.6 years (maximum, 12.8 years). Patients (n=10) with low preoperative LVEF (0.362±0.035) improved to 0.517±0.042 postoperatively (p=0.001). There was 1 late death in a patient with cystic fibrosis. Late reintervention was needed in 5 patients (8%). Late follow-up was available in 95% (n=59); all were acyanotic and 88% were in New York Heart Association functional class I/II.

Conclusions: Concomitant BCPS is a useful adjunct in repair of advanced EM with severe RV dilatation and dysfunction. Operation can be performed with low early mortality. Intermediate-term survival and quality of life is good to excellent, and transplantation can be delayed or avoided in the majority.