Cardiac magnetic resonance imaging for the assessment of ventricular function, geometry, and viability before and after surgical ventricular reconstruction

Abstract

Objective: Surgical ventricular reconstruction is a treatment option for patients with apical akinesia or dyskinesia. The Surgical Treatment for Ischemic Heart Failure trial recently demonstrated its safety but no added benefit to bypass surgery, although the trial's inclusion criteria did not contain shape or viability parameters. However, we evaluated cardiac magnetic resonance-derived parameters as potential predictors of function after surgical ventricular reconstruction.

Methods: In 24 patients with cardiac magnetic resonance before and after surgical ventricular reconstruction, we assessed cardiac volumes, function, scar, and geometry (sphericity index, short to long axis; apical conicity index, apical to short axis; apical volume index, apical to basal volume).

Results: Surgical ventricular reconstruction significantly reduced ventricular volumes (-64.2%) and increased global ejection fraction by 12% (P < .01). The sphericity index was increased by surgical ventricular reconstruction (0.60 ± 0.07 vs. 0.76 ± 0.13. P < .05) indicative of ball shapes. The apical to short axis (0.71 ± 0.13 to 0.58 ± 0.09) and apical to basal volume (0.45 ± 0.08 to 0.26 ± 0.11) decreased, consistent with aneurysm removal. The preoperative ventricles contained 25% ± 14% of scar (apical: 72% ± 8%, midcavity: 38% ± 14%, basal region: 10% ± 12%). Patients with ejection fraction improvement greater than 12% had less basal scar preoperatively and showed greater apical to basal volume reduction than those with ejection fraction improvement less than 12%. Basal wall motion scores did not differ between the subgroups. However, multivariable analysis identified only ejection fraction and urgency of operation as independent risk predictors.

Conclusions: The assessment of basal viability and the determination of the apical to basal volume may allow identifying the subgroup of patients who potentially derive a benefit from surgical ventricular reconstruction. A larger study is needed to support this conclusion.