Myocardial perfusion and left ventricular function in long-term follow-up and prognosis of electrostimulation cardiomyoplasty

Twenty two patients with congestive cardiac failure treated surgically by dynamic cardiomyoplasty (CMP) with m. latissimus dorsi were examined. Myocardial perfusion was assessed with (199)TlCl scintigraphy combined with dipyridamole stress-test. In order to obtain direct evidence of myocardial perfusion from muscular flap we also injected a bolus of (99m)Tc into a. thoracodorsalis, with simultaneous blood sampling from coronary sinus. Haemodynamic parameters were assessed using radionuclide angiography.

In a year of follow-up all the patients were assigned to one of two groups: eleven patients demonstrated improvement in clinical status (first group) and in another group comprising eleven persons no positive effect or deterioration were obvious (second group). The patients of the first group before operation revealed two times less persistent defect size than patients of the second group. Analysis of integral index of persistent defect revealed more expressive differences between groups. Before the surgical treatment the patients with improvement in clinical status after cardiomyoplasty demonstrated greater size of reversible defect in comparison with patients of the second group. In the second group coronary fraction of thallium accumulation was 1.4 times higher in comparison to the first group, as the result of myocardial hypertrophy in patients with bad prognosis. There were no significant differences between the two groups in Il/m level before cardiomyoplasty. Before the surgical treatment the patients with improvement in clinical status after cardiomyoplasty demonstrated greater ejection fraction in comparison with patients of the second group.

Cardiomyoplasty led to a decrease in the mean size of reversible defects due to indirect revascularisation. This hypothesis was testified to by the fact that in patients after cardiomyoplasty nuclide appeared in coronary sinus at 10-12th seconds after injection into artery thoracodorsalis through anastomoses between the latissimus dorsi muscle and the myocardium. The time of appearance of the second wave of rise gamma-counting in blood samples from coronary sinus reflects the repeated entry of radiopharmaceutical in myocardium after recirculation.