Postoperative assessment of a modified surgical approach to repair of tetralogy of Fallot. Long-term follow-up.

BACKGROUND

After repair of tetralogy of Fallot, right ventricular (RV) dilation has been associated with increased risk of ventricular arrhythmias and sudden death. To address this, a modified repair was developed.

METHODS AND RESULTS

We followed two postoperative groups: group 1 (n = 20) received repair of tetralogy of Fallot with the modified technique with transatrial ventricular septal defect closure, a short infundibular incision with avoidance of muscle resection, and patch expansion of the RV outflow tract; group 2 (n = 22) received repair of tetralogy of Fallot by the traditional technique with ventricular septal defect closure through a ventriculotomy with resection of obstructing muscle. Six patients were excluded from further follow-up: two patients, one in each group, who required RV-pulmonary artery conduit placement at original repair; one patient in group 1 who developed double-chamber RV; and three patients, two in group 1 and one in group 2, who were lost to our follow-up < 5 years postoperatively. We compared postoperative findings > 10 years after repair. Despite similar residual RV outflow tract stenosis and obligatory pulmonary insufficiency by examination and Doppler echocardiography, RV size was smaller in the modified group, as reflected by RV/left ventricle on M-mode echocardiography (0.66 +/- 0.22 versus 0.81 +/- 0.17, P = .02), cardiothoracic ratio (0.53 +/- 0.04 versus 0.58 +/- 0.06, P = .03), and QRS duration (126 +/- 19 versus 143 +/- 23, P = .03). RV systolic function was more impaired in group 2, as reflected by decreased systolic tricuspid annulus excursion on two-dimensional echocardiography. Exercise endurance time was significantly higher in group 1 patients. Lown grade 4 ventricular ectopy on ambulatory ECG was present in three patients in group 2 and none in group 1.

CONCLUSIONS

The modified technique results in significantly less RV dilation and better preservation of RV function at late follow-up.