Impact of cardiac rehabilitation exercise program on left ventricular diastolic function in coronary artery disease: a pilot study

Abstract

Diastolic dysfunction is common in coronary artery disease (CAD). Exercise-based cardiac rehabilitation (CR) improves survival and quality of life but its effect on diastolic function is unclear. We sought to determine the impact of CR on diastolic function. We conducted a prospective study of CAD patients referred for 3-month outpatient CR, with pre-CR and post-CR echocardiograms. Twenty-five outpatients (age [mean ± SD], 66 ± 11 ! years; 7 [28 %] women; 22 [88 %] with recent acute coronary syndrome) were recruited upon beginning CR; one patient lacking follow-up was excluded from analysis. Before CR, patients' mean ejection fraction was 61 ± 7 %; regional wall motion score index was 1.18 ± 0.28; and left ventricular diastolic dysfunction existed in 21 (88 %). Of the 24 (96 %) patients with post-CR follow-up, 12 (50 %) had improved diastolic function, 2 of the 24 (8 %) had normal diastolic function throughout, nine (38 %) remained at the same grade, and one (4 %) had worsened diastolic function. The E/e' ratio improved significantly after CR (11.9 ± 4.5 vs. 10.7 ± 4.5; P = .048). Fourteen patients with normal or improved diastolic function had a greater decrease in left atrial volume index (-4.2 ± 6.3 vs. 1.6 ± 6.3 mL/m(2); P = .04) and a greater increase in peak untwisting rate (20 ± 36 vs. -42 ± 45 °/s; P = .003) than did patients with no diastolic improvement. Three-month, exercise-based CR was associated with improved left ventricular diastolic function in half of our patients. Further large studies are needed to clarify the effect of CR on diastolic dysfunction in patients with CAD.