Genetic studies on the arrhythmia in acute myocardial infarction with special reference to serum free fatty acid level.

The serious arrhythmias have been regarded as one of the important complications in patients with acute myocardial infarction. Clinical and experimental observations were made of the arrhythmogenecity in acute myocardial infarction in special reference to the high free fatty acidemia (HFFA). The results obtained were as follows: (1) The incidence of arrhythmia in 35 patients with acute myocardial infarction, in whom the serum free fatty acid (FFA) value was measured, was 84.0%. (2) The serum FFA values of arrhythmic patients were significantly higher than those of patients without arrhythmia (P less than 0.001). (3) it was also revealed that the serum FFA values of patients with ventricular premature contraction (VPC) were significantly higher than those of non-arrhythmic patients (P less than 0.001). (4) each of the rate of incidence of VPC in total arrhthmic patients and the serum FFA value on the day of attack was significantly higher than that on the following days, respectively. (5) HFFA was experimentally produced in infaracted dog with the coronary ligation by the infusion of Intralipid and heparin and its effect on the ventricular fibrillation threshold (VFT) was observed. The VFT was markedly decreased promptly after the coronary ligation and a trend of natural recovery of the VFT was seen in a period later than 60 minutes after the coronary ligation. The recovery phase was significantly suppressed by the treatment producing HFFA (P less than 0.01). The deleterious effect of HFFA on the VFT was prevented by the treatment with glucose and insulin solution (GI solution) (P less than 0.02). From these results, it is postulated that HFFA in patients with acute myocardial infarction acts as an arrhythmogenic factor by lowering the VFT and GI solution prevents the occurrence of arrhythmia by lowering the serum FFA value.