M. Di Donato

Efficacy of endoventricular patch plasty in large postinfarction akinetic scar and severe left ventricular dysfunction: comparison with a series of large dyskinetic scars

BACKGROUND Many believe that dyskinesia is the only predictor of favorable surgical outcome after large myocardial infarction and that akinetic scars do not recover well in patients with globally depressed ventricular function. METHODS This study evaluates clinical and hemodynamic results of endoventricular circular patch plasty in patients with either large akinetic scar (n = 51) or large dyskinetic scar (n = 49) and depressed left ventricular function (ejection fraction <30%). Groups were comparable for symptoms, indication for operation, and delay from myocardial infarction. Heart failure was a major indication for operation in both groups. Coronary grafting was performed in 98% of patients: 10 had mitral valve repair or replacement, and 47 patients with preoperative ventricular arrhythmias had cryotherapy. In-hospital mortality was 12% (five patients in the akinetic group [10%] and seven in the dyskinetic group [14%]). RESULTS Results showed an early and late improvement in New York Heart Association functional class and ejection fraction (from 23% +/- 5% to 31% +/- 11% to 40% +/- 13% in akinetic patients and from 23% +/- 6% to 41% +/- 10% to 41% +/- 12% in dyskinetic patients). Ventricular tachycardia was reduced significantly in both groups early and late after the operation. CONCLUSION We conclude that in patients with either large akinetic or dyskinetic scar and severe left ventricular dysfunction, endoventricular circular patch plasty associated with coronary grafting and cryotherapy, when indicated, provides surviving patients with significant improvement in cardiac function. This approach can be considered as an alternative to heart transplantation in patients with severe left ventricular dysfunction.

Late hemodynamic results after left ventricular patch repair associated with coronary grafting in patients with postinfarction akinetic or dyskinetic aneurysm of the left ventricle

This study reports hemodynamic, electrophysiologic, and clinical results in 171 patients (157 men and 14 women, mean age 57 +/- 8 years) 1 year after endoventricular circular patch repair and coronary grafting for postinfarction left ventricular dyskinetic or akinetic aneurysm. All patients had hemodynamic and electrophysiologic study before the operation and early and 1 year after the operation. The vast majority of aneurysms were anterior (n = 166), with a mean delay from infarction of 43 +/- 50 months. Fifty-two percent of patients were in New York Heart Association class III or IV, and preoperative ejection fraction was less than 40% in the majority of them (75%). Preoperative clinical ventricular tachycardia was present in 25 patients and was inducible in 59 patients. All patients had endoventricular circular patch repair with a synthetic (n = 99) or autologous patch (n = 72); 96% had associated coronary grafting with a mean number of bypass grafts of 1.9 +/- 0.9. Results at 1 year demonstrated a significant increase in ejection fraction (from 36% +/- 13% to 46% +/- 12% (p < 0.0001) and a significant reduction in ventricular volumes (end-diastolic volume index from 116 +/- 5 to 94 +/- 29 ml/m2 and end-systolic volume index from 77 +/- 45 to 53 +/- 25 ml/m2, p < 0.0001). New York Heart Association functional classification was significantly improved (2.6 +/- 0.9 vs 1.4 +/- 0.6, p < 0.0001) and ventricular tachycardias were almost suppressed (no documented clinical ventricular tachycardias and 8% incidence of inducible ventricular tachycardias after 1 year, chi 2 < 0.001). Patients who benefit most from the operation are those with more severe preoperative left ventricular dysfunction (i.e., ejection fraction < 30%), more frequent ventricular arrhythmias, and larger ventricular volumes. At regression analysis, critical disease of the right coronary artery was the only independent predictor of unsatisfactory pump improvement (as evaluated by postoperative increase of ejection fraction < 10 absolute points). In conclusion, in our large series of patients operated on by one surgical team between 1988 and 1993, who were studied hemodynamically both before and after the operation, endoventricular circular patch repair of left ventricular aneurysm associated with coronary grafting definitely improves left ventricular pump function and clinical status 1 year after the operation.

Results of nonguided subtotal endocardiectomy associated with left ventricular reconstruction in patients with ischemic ventricular arrhythmias

We analyzed the effects of nonguided endocardiectomy in patients with ischemic ventricular arrhythmias who underwent reconstructive operations for postinfarction left ventricular aneurysm. A total of 106 patients among 287 consecutive patients had spontaneous or inducible ventricular tachycardia (49 spontaneous and 57 inducible). Cryotherapy was done in 67 patients and coronary revascularization was done in 98%. Patients underwent complete hemodynamic study including programmed ventricular stimulation before and early after operation. Thirty-seven patients underwent hemodynamic evaluation after 1 year. The hospital mortality rate was 7.5%. At early and late studies the mean ejection fraction was significantly increased. Ventricular tachycardia was no longer inducible in 92% of patients after operation; only two patients had spontaneous ventricular tachycardia early after operation. At late study 10.8% of patients had inducible ventricular tachycardia and no spontaneous ventricular tachycardia was documented. All surviving patients had clinical follow-up (mean 21.3 months, range 2 to 64 months). There were eight late deaths and no episodes of ventricular tachycardia or syncope that necessitated hospitalization. In conclusion, nonguided, extended endocardiectomy associated with left ventricular reconstruction is safe and effective in curing ischemic spontaneous and inducible ventricular tachycardia.

Surgical treatment of ventricular septal defect complicating acute myocardial infarction. Experience of a north Italian referral hospital

The purpose of our study was to evaluate the clinical outcome of postinfarction ventricular septal defect (VSD) of patients referred to our institution for surgical treatment, by assessing the role of several operative, pre- and post-operative variables on mortality. The medical records of 58 consecutive patients (mean age 73+/-7 years), operated on after 14+/-12 days from the acute myocardial infarction were retrospectively reviewed and the data were analyzed. Associated procedures were left ventricular reconstruction in 13 patients and aortocoronary bypass grafting in 47 (81%). The overall operative, in-hospital mortality rate was 52% (75% in patients operated on within the first week and 16% if time from infarct to surgery was >3 weeks). Time from AMI to surgery and time from hospital admission to operation were significantly shorter in non-survivors (p=0.003 and 0.012, respectively). Other pre-operative variables significantly associated with mortality were: cardiogenic shock, pulmonary pressure, VSD diameter. In conclusion, time from AMI to operation appears to be a very important prognostic factor. However, size of VSD and hemodynamic conditions significantly influence the mortality. Moreover, concomitant procedures of revascularization can be safely performed, when required, as actually occurs in most cases.

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

Objective To investigate left ventricular elastance (Emax) and effective arterial elastance (Ea) in postinfarction left ventricular aneurysm and evaluate their role in left ventricular function improvement after endoventricular circular patch plasty (EVCPP). Ventriculoarterial coupling has never been studied in these patients. Patients 22 consecutive patients (49 to 73 years) with left ventricular anterior aneurysm. Methods Haemodynamic studies were done before and two weeks after EVCPP. Ventriculography was performed during atrial pacing (100 beats/min). Pressure/volume loops were analysed and derived parameters measured. Emax was estimated 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 diastolic volume index from mean (SD) 155 (53) to 106 (29); end systolic volume index from 112 (51) to 62 (30) ml/m2 (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 between left ventricular pressure upstroke and peak systolic pressure decreased, from 237 (39) to 191 (41) ms (p < 0.0001), paralleling morphological changes in pressure tracings. Conclusions After EVCPP, ventriculoarterial coupling improves because of the fall in Ea caused by end systolic pressure reduction. The improvement is related to aortic pressure waveform changes and improved relaxation.

‘Programmed’ Left Ventricular Angiography: A New Method for Assessing Left Ventricular Compliance

In the present study a new method for evaluating left ventricular chamber compliance is reported. We induced a programmed postextrasystolic beat during routine left ventricular angiography through a temporary pacing catheter, placed at the sinoatrial junction (S1-S1 = 600 ms; S1-S2 = 400 ms; S2-S3 = 800 ms). Thirty-two patients with documented critical coronary artery disease and 5 normal subjects represent the study group. The method allows to have two couples of end-diastolic pressure and end-diastolic volume and we calculated the modulus of chamber stiffness with the formula: K = (1n EDP 3 - 1n EDP 1)/(EDVI 3 - EDVI 1), where EDP 1-3 and EDVI 1-3 are end-diastolic pressure and end-diastolic volume index in basal beat and in the postextrasystolic pause, respectively. Left ventricular chamber compliance (dV/dP) and specific compliance (dV/VdP) were also calculated. In order to assess the clinical value of the method, we divided the patients with coronary artery disease into three groups: 12 patients had angina and no previous myocardial infarction; 15 had a previous myocardial infarction and responded to postextrasystolic potentiation with an increase in left ventricular ejection fraction greater than or equal to 0.08 and 5 patients had myocardial infarction and did not respond to postextrasystolic potentiation. Diastolic indices showed significant differences between subgroups; patients with more severe disease and with systolic dysfunction had the highest values of the modulus of chamber stiffness and the lowest values of chamber compliance. Moreover, these indices were not correlated with basal end-diastolic volumes, but they were directly and significantly correlated with the actual increase in left ventricular filling.