Evaluation of Left Ventricular Systolic Function after Pulmonary Valve Replacement Using Cardiovascular Magnetic Resonance Imaging

摘要

Following reparative surgery for tetralogy of Fallot or critical pulmonary stenosis(PS),patients frequently present with severe right ventricular(RV)volume overload due to pulmonary regurgitation,resulting in decreased RV function.Surgical pulmonary valve replacement(PVR)is known to improve RV function,but changes in left ventricular(LV)function after PVR have rarely been described.We sought to determine the midterm results regarding LV systolic function after PVR using cardiac MRI in 40 consecutive patients with repaired TOF(31 patients)or PS(9 patients)with an age of 29±9 years who underwent PVR from 2006 to 2011 at a single center.Cardiac MRI RV and LV volumes before and after PVR were analyzed.Demographics,clinical variables,cardiopulmonary bypass duration,and medications were reviewed.LV ejection fraction(LVEF)increased from(54±8)to(57±6)%(P=0.02).Before PVR,26 patients had depressed LVEF of(49±5)%(range 36– 54%).In this group,LVEF increased by(7±7)%(P<0.0001)after PVR.Low LVEF before PVR was correlated with increased LVEF after PVR(regression coefficient-0.7,R 2=0.59,P<0.0001).Demographics,medications,prior pregnancies,and cardiopulmonary bypass duration had no effect on LVEF after PVR.The increase in LVEF was most significant in patients with low pre-PVR LVEF.