IMPROVEMENT OF LEFT-VENTRICULAR FUNCTION AND CARDIOVASCULAR NEURAL CONTROL AFTER ENDOVENTRICULOPLASTY AND MYOCARDIAL REVASCULARIZATION

Objective: To investigate the effects of endoventriculoplasty (EVP) an d myocardial revascularization on left ventricular function and on sym pathovagal balance modulating sinus node and vasomotor activity, we st udied patients with left anterior, septal or anteroseptal ventricular aneurysm, before and after surgery. It has been demonstrated that, com pared to the standard aneurismectomy, EVP associated with coronary gra fting has a lower operative mortality and improves ventricular functio n, clinical status and prognosis. Methods: We collected pre-and post-o perative echocardiographic and angiographic data to determine morpholo gical and hemodynamic changes. The pre-and post-operative neural cardi ovascular control was assessed by power spectrum analysis of heart rat e and systolic arterial pressure (SAP) variabilities during rest and t ilt. Results: As expected, post-operative Ventricular function improve d significantly: ejection fraction increased from 33 +/- 2 to 46 +/- 3 % (p < 0.01) when assessed by echocardiography and from 40 +/- 4 to 55 +/- 5% (p < 0.01) when assessed by angiography; left ventricular end- diastolic pressure fell from 22 +/- 3 to 13 +/- 2 mmHg (p < 0.05). Pre -operatively sympathovagal balance responsiveness was blunted: tilt te st did not induce, in respect to resting values,: any significant chan ge in low frequency (LF,,) and high frequency (HFRR) components of RR variability (in normalized units, n.u.) and in LFSAP. Post-operatively , tilt induced significant changes in LFRR and HFRR (in n.u.), in LF/H F ratio and LFSAP in respect to resting values. The pre-and post-opera tive percent differences -delta %-, from rest to tilt, of LFRR, HFRR, LF/HF and LFSAP were also significantly different (p < 0.01, p < 0.05, p(0.05, p < 0.05). In addition, we compared data obtained from surviv ors arid non-survivors (6 out of 19 patients died within 4 months beca use of heart failure). Non-survivors were characterized by significant ly lower RR variance (184 +/- 80 vs. 1193 +/- 309 ms(2) at rest, 196 /- 87 vs. 546 +/- 104 ms(2) during tilt, p < 0.05) and lower LFRR (15 +/- 7 vs. 61 +/- 6 at rest, 23 +/- 10 vs. 58 +/- 6 during tilt, in n.u ., p < 0.01). Conclusions: (1) The improvement of ventricular function induced by EVP and myocardial revascularization is accompanied by a r estored capability to oscillate of cardiovascular neural regulatory me chanisms; (2) the drastic reduction of variance and LF component from RR variability seems to be associated with an ominous outcome. (C) 199 8 Elsevier Science B.V.