Ventricular energetics in endoventricular circular patch plasty for dyskinetic anterior left ventricular aneurysm

Background. The endoventricular circular patch plasty (Dor procedure) applies to patients with a left ventricular dysfunction due to an ischemic dilated ventricle. In the present study, we analyzed left ventricular energetics in patients who underwent the Dor procedure. Methods. We measured left ventricular contractility (end-systolic elastance; Ees), afterload (effective arterial elastance; Ea), and efficiency (ventriculoarterial coupling; Ea/Ees, and the ratio of stroke work and pressure-volume area; SW/PVA) based on the cardiac catheterization data before and after the Dor procedure in 8 patients with a postinfarction dyskinetic anterior left ventricular aneurysm. Concomitant procedures included coronary artery bypass grafting in all patients, mitral valve repair in one patient, and cryoablation in one patient. End-systolic elastance (Ees) and Ea were approximated as follows: Ees = mean arterial pressure/minimal left ventricular volume, and Ea = maximal left ventricular pressure/(maximal left ventricular volume-minimal left ventricular volume), and thereafter Ea/Ees and SW/PVA were calculated. The left ventricular volume was normalized with the body surface area. Results. End-systolic elastance (Ees) increased after the Dor procedure (from 1.15 ± 0.60 to 1.86 ± 0.84 mm Hg·m²·mL^-1, p < 0.01), thus resulting in an improvement in Ea/Ees and SW/PVA (from 2.94 ± 1.11 to 1.64 ± 0.49, p < 0.01, and from 0.426 ± 0.110 to 0.559 ± 0.082, p < 0.01, respectively), even though Ea did not substantially change (from 2.96 ± 0.78 to 2.74 ± 0.55 mm Hg·m²·mL^-1, p = 0.4). Conclusions. Left ventricular contractility and efficiency improves after the Dor procedure in patients with a dyskinetic anterior left ventricular aneurysm. However, afterload does not change. The use of appropriate afterload-reducing therapy thus plays an especially important role in the management of patients who undergo the Dor procedure.