['Records of patients who had repair of sinus venosus defect (SVD) between 1970 and 2008 were reviewed to predict very long-term outcome.', 'Repairs occurred in 104 consecutive patients (51 men), aged 29 +/- 23 years (range, 1 to 70 years). Seven had isolated SVD and 97 had associated lesions that required concomitant operations. Five patients had preoperative arrhythmias; 24 (23%) were in New York Heart Association (NYHA) class III to V. Single-patch repair was done in 91 patients, caval translocation (Warden) in 7, and double-patch in 6.', 'Ten late deaths during 38 years of follow-up (mean, 15 +/- 20 years). Survival was 97% +/- 2% and 79% +/- 7% at 10 and 30 years. Thirty-one (29%) long-term survivors experienced 47 complications, including chronic/recurrent supraventricular tachycardia in 28, heart failure in 5, permanent pacing in 8, cerebrovascular accident in 3, and unrelated cardiac reoperation in 3. At 30 years, freedom from adverse cardiac events was 47% +/- 9%, from supraventricular tachycardia, 50% +/- 9%; from permanent pacing, 83 +/- 6%; and from cerebrovascular accident, 96% +/- 2%. Follow-up age was 42 +/- 23 years (range, 5 to 82 years); 74 patients (79%) were in NYHA class I, and 15 and 5 were in class II and III to IV, respectively. Baseline cardiac rhythm was sinus in 75 patients (84%), atrial fibrillation in 11 (12%), and paced in 8. Nine patients had moderate/severe pulmonary hypertension, and 8 had left ventricular dysfunction. Only older age at operation was associated with lower survival (p = 0.003), freedom from cardiac events (p = 0.001), supraventricular tachycardia (p = 0.009), and permanent pacing (p = 0.002). Repair before age 20 was associated with lower NYHA class at follow-up (p = 0.01).'] Does age at repair affect the very long-term outcome of sinus venosus defect?