Echocardiographic Assessment of Dynamic Changes in Left Ventricular Shape.
Changes in resting left ventricular shape have been related to underlying left ventricular dysfunction and may precede detectable hemodynamic abnormalities. The significance of dynamic changes in left ventricular shape has only recently been examined. In patients with systolic left ventricular dysfunction, dynamic changes in heart shape correlate strongly with exercise duration. Patients whose ventricles develop a more spheric left ventricular shape during exercise have diminished exercise capacity compared to patients whose ventricles become more ellipsoidal. In patients having mitral valve surgery for chronic, severe mitral regurgitation, mitral valve repair results in improved rest and exercise ejection indexes when compared to valve replacement, primarily due to a marked reduction in end-systolic stress and maintenance of a more ellipsoidal left ventricular shape. Potential mechanisms for these observations are discussed.
Tischler
Marc D.
MD
Medical Center Hospital of Vermont, McClure 1, Burlington, VT 05401.