Effects of reconstructive surgery for left ventricular anterior aneurysm on ventriculoarterial coupling

Objective-To investigate left ventricular elastance (Emax) and effective ar terial elastance (Ea) in postinfarction left ventricular aneurysm and evalu ate their role in left ventricular function improvement after endoventricul ar circular patch plasty (EVCPP). Ventriculoarterial coupling has never bee n studied in these patients. Patients-22 consecutive patients (49 to 73 years) with left ventricular ant erior aneurysm. Methods-Haemodynamc studies were done before and two weeks after EVCPP. Ven triculography was performed during atrial pacing (100 beats/min). Pressure/ volume loops were analysed and derived parameters measured. Emax was estima ted by applying the "single beat" method. Ea was calculated as end systolic pressure/stroke volume. Results-Left ventricular volumes and Ea decreased after surgery: end diasto lic volume index from mean (SD) 155 (53) to 106 (29); end systolic volume i ndex from 112 (51) to 62 (30) ml/m(2) (both p < 0.0001); Ea from 1.65 (0.70 ) to 1.39 (0.41) mm Hg/ml (p = 0.04). Ejection fraction and Emax increased, without significant changes in stroke volume and work. The decrease in Ea was directly correlated with its preoperative value. The time interval betw een left ventricular pressure upstroke and peak systolic pressure decreased , from 237 (39) to 191 (41) ms (p < 0.0001), paralleling morphological chan ges in pressure tracings. Conclusions-After EVCPP, ventriculoarterial coupling improves because of th e fall in Ea caused by end systolic pressure reduction. The improvement is related to aortic pressure waveform changes and improved relaxation.