Reverse remodeling and improved regional function after repair of left ventricular aneurysm.

Abstract

Changes in regional left ventricular mechanics after anteroapical aneurysm repair in human subjects can be studied noninvasively by means of magnetic resonance tagging. We hypothesized that left ventricular intramyocardial function would improve throughout the left ventricle after repair. We studied 6 male patients with a left ventricular anteroapical aneurysm (mean age +/- SD, 63 +/- 5 years) using magnetic resonance tagging 3 +/- 1 weeks before and 6 +/- 1 weeks after aneurysm repair, coronary artery bypass grafting, and mitral valve repair (n = 2). Breath-hold tagged imaging spanned the left ventricle in the short axis from apex to base. Left ventricular mass, end-diastolic and end-systolic volume, and ejection fraction were measured. Two-dimensional strain analysis was applied; averaged for the apical, middle, and basal left ventricle and the whole left ventricle; and expressed as greatest lengthening (similar to wall thickening), greatest shortening, and angular deviation of the lengthening strain from the radial direction. After aneurysm repair, left ventricular mass decreased from 373 +/- 27 to 333 +/- 25 g (P <.05), end-diastolic volume from 212 +/- 22 to 168 +/- 18 mL (P <.005), and end-systolic volume from 188 +/- 26 to 113 +/- 18 mL (P <.005); ejection fraction improved from 13% +/- 4% to 23% +/- 4% (P <.005). For the whole left ventricle, lengthening strain increased from before to after the operation (8% +/- 1% to 10% +/- 1%, P <.01). Most of the improved lengthening occurred at the middle left ventricle (8% +/- 1% to 11% +/- 1%, P <.01), in the base (8% +/- 1% to 10% +/- 1%, P <.05), and in the inferior wall (9% +/- 1% to 12% +/- 1%, P <.05). Lengthening tended to become more radially oriented, decreasing from 31 degrees +/- 3 degrees to 27 degrees +/- 3 degrees (P =.10). Shortening strain did not change (10% +/- 1% to 11% +/- 1%, P = not significant). Left ventricular aneurysm repair is associated with reverse remodeling and an improvement in the extent and orientation of intramyocardial function, especially at the middle and basal left ventricle and inferior wall.