Left ventricular torsion during exercise in patients with and without ischemic response to exercise echocardiography

Abstract

Introduction and objectives: Left ventricular torsion decreases during transmural myocardial ischemia, but the effect of exercise on left ventricular torsion has not been widely studied. We hypothesized that exercise-induced ischemia may impair left ventricular torsion. Therefore, our aim was to study the effects of exercise on left ventricular torsion in patients with an ischemic response to exercise echocardiography and in patients with a normal response.

Methods: A retrospective analysis was performed in 172 patients with ejection fraction ≥ 50% who were referred for exercise-echocardiography and studied by speckle imaging at rest, peak and postexercise. Torsion was defined as apical rotation - basal rotation (in degrees) / left ventricular length (in centimeters). A total of 114 patients had a normal exercise echocardiography and 58 patients had an ischemic response to exercise echocardiography.

Results: Patients with ischemic response to the test exhibited less basal rotation at peak exercise (+0.30° [2.39°] vs -0.65° [2.61°] in the normal group; P = .03), whereas peak apical rotation was similar (ischemic response to the test, 7.80° [3.51°]; normal response, 7.27° [3.28°]; P =.36). Torsion at peak exercise was also similar (1.07° [0.60°] in the ischemic response to the test group vs 1.16° [0.57°] in normal group; P =.37). A more impaired peak basal rotation was found in patients with anterior or anterior+posterior involvement (anterior ischemic response, +1.22° [2.45°]; anterior + posterior ischemic response, -0.20° [2.25°]; posterior ischemic response, -0.71° [1.96°]; normal response, -0.65° [2.60°]; P =.02).

Conclusions: Basal rotation at peak exercise is impaired in patients with an ischemic response to exercise echocardiography, particularly in those with anterior involvement. Apical rotation and torsion are similar to those in patients with normal exercise echocardiography.

Keywords: Coronary artery disease; Enfermedad coronaria; Ischemia; Isquemia; Left ventricular torsion; Torsión ventricular izquierda.