Ventricular geometric characteristics and functional benefit of mild right ventricular outflow tract obstruction in patients with significant pulmonary regurgitation after repair of tetralogy of Fallot
Journal
American Heart Journal
Journal Volume
167
Journal Issue
4
Pages
555-561
Date Issued
2014
Author(s)
Chiu H.-H.
Yang M.-C.
Abstract
Background Right ventricular (RV) outflow tract obstruction (RVOTO) might protect the RV from adverse remodeling caused by significant pulmonary regurgitation (PR) in patients with repaired tetralogy of Fallot (rTOF), but the underlying mechanisms and influences on exercise tolerance remain unclear. This study sought to investigate the impacts from mild RVOTO on ventricular remodeling and exercise capacity in rTOF. Methods Eighty-five rTOF patients with a PR fraction ?20% were assessed with cardiac magnetic resonance, cardiopulmonary exercise test, and echocardiography. Patients with a peak RVOT pressure gradient 20-50 mmHg were considered to have mild RVOTO (n = 29), while those with a gradient <20 mmHg had isolated PR (n = 56). Results Comparing to patients with isolated PR, patients with combined PR and mild RVOTO had smaller RV and RVOT dimension, better RV and left ventricular (LV) ejection fraction (EF), and superior exercise capacity. PR severity and RV mass/volume ratio were similar between these 2 groups. LVEF coupled with RVEF only in patients with isolated PR. In multivariate analysis, smaller RVOT dimension was independently related to smaller RV dimension (P <.001) and higher RVEF (P =.005). Furthermore, mild RVOTO was independently associated with higher peak oxygen consumption (P =.014) and oxygen uptake efficiency slope (P =.005). Conclusions Patients with combined PR and mild RVOTO had better RV remodeling and exercise capacity compared to those with isolated PR. Our findings confirm the benefits from mild residual RVOTO support a policy of conservative RVOTO relief at repair. ? 2014 Mosby, Inc.
SDGs
Other Subjects
oxygen; article; bicycle ergometer; cardiopulmonary exercise test; cardiovascular magnetic resonance; cohort analysis; controlled study; disease severity; exercise physiology; Fallot tetralogy; female; functional assessment; heart left ventricle ejection fraction; heart left ventricle endsystolic volume; heart left ventricle mass; heart right ventricle function; heart right ventricle outflow tract obstruction; heart right ventricle pressure; heart ventricle remodeling; heart ventricle size; human; major clinical study; male; nuclear magnetic resonance scanner; oxygen consumption; oxygen gas analyzer; priority journal; pulmonary valve insufficiency; tissue Doppler imaging; Adult; Cardiac Surgical Procedures; Echocardiography; Female; Follow-Up Studies; Heart Ventricles; Humans; Magnetic Resonance Imaging, Cine; Male; Postoperative Complications; Prognosis; Pulmonary Valve Insufficiency; Retrospective Studies; Severity of Illness Index; Tetralogy of Fallot; Ventricular Function, Left; Ventricular Outflow Obstruction; Ventricular Pressure; Ventricular Remodeling
Type
journal article