Plasma concentrations of endothelin during thrombolysis, in patients with anterior, inferior myocardial infarction and unstable angina

Background Endothelin is a recently discovered endothelium derived vasoconstrictive peptide. Studies have shown that Endothelin-1 (ET-I) increases in acute myocardial infarction (AMI). Methods: The aim of the study was to verify the plasma endothelin levels during thrombolysis and reperfusion according to localization and size of AMI (anterior/inferior) and in patients with unstable angina (UA) undergoing thrombolysis. Eighty patients, 18 F/62 M, hospitalized for suspected AMI (Ist episode) within 4 hrs from the onset of symptoms, suitable for thrombolysis, Killip class I-II were investigated. Plasma endothelin levels were checked before thrombolysis, at I hr, and 2 hrs after starting thrombolysis. Results: All patients admitted to the study met the reperfusion criteria. Endothelin data: Anterior AMI group: 36 patients (mean age 61.7+/-7 yrs): sample at entry 7.36+/-3.81, at I hr 7.69+/-3.86, at 2 hrs 10.83+/-5.19 pg/ml (p<0.001). Inferior AMI group: 23 patients (mean age 62.8+/-8 years): at entry 6.42+/-4.98, at I hr 7.11+/-5.31, at 2 hrs 8.07+/-5.01 pg/ml. UA group: 21 patients (mean age 59.1+/-6 yrs at entry 4.32+/-2.45, at 1 hr 4.56+/-4.18, at 2 hrs 5.21+/-4.28 pg/ml. Conclusion: Our data show that plasma endothelin levels are raised within 2 hrs of uncomplicated AMIs subjected to thrombolysis. Further, our results show that endothelin levels are higher in anterior than in inferior AMI (p<0.05). The patients with UA did not show any endothelin increase during thrombolysis and reperfusion. These data suggest that localization and size of AMI determine endothelin plasma levels.