Author + information
- Received August 6, 1990
- Revision received January 8, 1991
- Accepted January 21, 1991
- Published online July 1, 1991.
- ↵*Address for reprints: Duncan J. Stewart, MD, Division of Cardiology, Royal Victoria Hospital, 687 Pine Avenue West, Rm M4.76, Montreal H3A 1A1, Quebec, Canada.
Endothelin is a novel endothelium-derived vasoactive peptide with potent vasoconstrictor action in the coronary bed; however, its possible contribution to myocardial ischemia and infarction is not known. Plasma endothelin-1 concentration was measured with use of a radioimmunoassay in serial venous samples from 22 patients over a 72 h period after acute myocardial infarction (14 patients with uncomplicated infarction [group I] and 8 patients with hemodynamic or ischemic sequelae [group II]). Twenty-two normal subjects and seven patients with stable angina served as the control subjects.
Endothelin-1 levels in patients with stable coronary disease were not different from those of normal subjects (0.62 ± 0.56 and 0.76 ± 0.38 pg/ml, respectively). In group I, plasma levels of endothelin-1 rose sharply after myocardial infarction, reaching a peak of 4.95 ± 0.78 pg/ml at 6 h after the onset of chest pain (p < 0.05 compared with values in control subjects) and returning rapidly toward the normal range by 24 h. Patients with complicated infarction (group II) demonstrated a similar rapid increase in plasma endothelin-1 to a peak value of 8.29 ± 1.95 pg/ml; however, plasma endothelin-1 remained elevated in these patients, becoming significantly different from values in group I at 48 and 72 h.
There was no correlation between peak increases in creatine kinase and peak endothelin-1 in either group, suggesting that the stimulus for elevation of endothelin-1 was not myocardial necrosis itself. Furthermore, left ventricular ejection fraction did not correlate with the increase in endothelin-1 in group I patients, whereas there was a significant inverse relation between ventricular function and plasma endothelin-1 in group II.
Therefore, the rapid increase in plasma endothelin-1 associated with the onset of infarction suggests that this peptide may provide a marker of endothelial perturbation in the early phase of coronary ischemia or even contribute to alterations in myocardial perfusion. The sustained increase in plasma endothelin-1 in patients demonstrating complications of myocardial infarction might reflect continuing ischemia or marked depression in ventricular function in these patients.
- Received August 6, 1990.
- Revision received January 8, 1991.
- Accepted January 21, 1991.
- American College of Cardiology Foundation