Left ventricular function in adults with mild pulmonary insufficiency late after Fallot repair

Abstract

Objective - To assess left ventricular function in adult Fallot patients with residual pulmonary regurgitation. Setting - The radiology department of a tertiary referral centre. Patients - 14 patients with chronic pulmonary regurgitation and right ventricular volume overload after repair of tetralogy of Fallot and 10 healthy subjects were studied using magnetic resonance imaging. Main outcome measures - Biventricular volumes, global biventricular function, and regional left ventricular function were assessed in all subjects. Results - The amount of pulmonary regurgitation in patients (mean (SD)) was 25 (18)% of forward flow and correlated significantly with right ventricular enlargement (p < 0.05). Left ventricular end diastolic volume was decreased in patients (78 (11) v 88 (10) ml/m2; p < 0.05), ejection fraction was not significantly altered (59 (5)% v 55 (7)%; NS). No significant correlation was found between pulmonary regurgitation and left ventricular function. Overall left ventricular end diastolic wall thickness was significantly lower in patients (5.06 (0.72) v 6.06 (1.06) mm; p < 0.05), predominantly in the free wall. At the apical level, left ventricular systolic wall thickening was 20% higher in Fallot patients (p < 0.05). Left ventricular shape was normal. Conclusions - Adult Fallot patients with mild chronic pulmonary regurgitation and subsequent right ventricular enlargement showed a normal left ventricular shape and global function. Although the left ventricular free wall had reduced wall thickness, compensatory hypercontractility of the apex may contribute to preserved global function.