Clinical and electrophysiological characteristics of sustained ventricular tachycardia occurring 3 to 21 days after acute myocardial infarction.

Abstract

Patients with sustained ventricular tachycardia (VT) in the post-infarction period, especially more than 48 h after acute myocardial infarction (AMI), have a high mortality. However, clinical characteristics of these patients are unknown, since previous studies have not clarified the relationship between sustained VT and acute myocardial damage. To clarify the prognostic factors in patients with sustained VT in the early post-infarction period, we retrospectively surveyed 961 consecutive patients with AMI. Eleven patients (9 men and 2 women, aged 54 to 80 years) who had no previous myocardial infarction had at least one documented episode of sustained VT between 3 and 21 days after AMI. Late potentials were detected in 7 of 7 patients who underwent signal-averaged electrocardiography within 2 days after the first occurrence of VT. Entrainment was seen in 2 patients. The 5 patients who died in hospital had the following clinical characteristics: 1) cardiogenic shock, 2) extensive infarction, 3) a short interval from AMI to the onset of VT (mean +/- SD: 4 +/- 2 days), and 4) recurrent and refractory VT. In contrast, the 6 patients who survived had the following clinical characteristics: 1) no cardiogenic shock, 2) a relatively late occurrence of VT (mean = SD: 14 +/- 7 days), 3) few episodes of VT, and 4) no recurrence of VT during the follow-up period of 12 to 58 months. The occurrence of sustained VT within 3 weeks after AMI was influenced by the general condition of the patient, and the prognosis was mainly related to cardiac function.