Background Late postoperative arrhythmias and right ventricular dysfunction may occur after classic repair of tetralogy of Fallot.=Lown grade 2). Postoperative catheterization showed good hemodynamic results in 20 of 24 patients; 3 (12.5%) had moderate-to-severe pulmonary regurgitation, and 1 (4.2%) patient had right ventricular hypertension. Sustained ventricular tachycardia could not be induced in any of the 5 adult patients who underwent electrophysiological studies. One late death (caused by endocarditis) occurred in group B.Conclusions The right atrial approach significantly reduced the risk of life-threatening ventricular arrhythmias after repair of tetralogy of Fallot (P<.001) without increasing the incidence of supraventricular arrhythmias. Right ventricular dysfunction and severe pulmonary regurgitation were also more prevalent (P<.01) when the right ventricular approach was used. (Circulation. 1994;90(part 2):II-7-II-12.)