Spherical dilatation of the apex in failing left ventricles: a target for surgical remodelling techniques

The present study investigates the geometry of failing left ventricles with a special focus on apical deformation. A new surgical remodelling technique is evaluated.

In 124 patients with impaired left ventricular function (EF<40%) undergoing coronary artery bypass grafting (CABG) left ventricular (LV) geometry was evaluated by MRI scanning before and after surgery. Besides the sphericity index (SI) two further indices were calculated, longitudinal EF (LEF) and an apical conicity index (ACI). The results were compared to 15 patients with coronary heart disease and normal LV function and 10 test persons. In 35 patients with impaired LV function perpendicular apical compression (AC) stitches were placed.

In failing left ventricles indexed LV length increased (5.3 ± 0.6 cm/m2 vs. 4.7 ± 0.8 cm/m2 in control patients and 4.6 ± 0.3 cm/m2 in test persons, P=0.03). LEF was reduced (6% ± 4 versus 22% ± 6 and 19% ± 7 P=0.04). The classical SI was 0.56 ± 0.06 in heart failure patients, 0.50 ± 0.05 in control patients and 0.48 ± 0.04 in test persons. The ACI were 0.75 ± 0.06, 0.58 ± 0.06 and 0.57 ± 0.04 respectively (P<0.05), indicating a pronounced dilatation at the apex. After apical compression LEF improved to 15 ± 1%, the ACI to 0.64 ± 0.04 (P=0.04). LVEDV (166 ± 11 mL [AC] vs. 196 ± 14 mL [without AC]) as well as LV-EF (48 ± 3% [AC] vs. 36 ± 2% [without AC]) significantly improved only after remodelling (P<0.05).

Apical compression improved ventricular geometry and ventricular function in patients with dialatation of the left ventricular apex.