Is it justifiable today to perform thrombolysis in only one fifth of the patients with myocardial infarct?
Sarasin, C.; Pfisterer, M.; Weiss, P.
Schweizerische Medizinische Wochenschrift 122(11): 369-374
1992
ISSN/ISBN: 0036-7672 PMID: 1557615 Document Number: 388199
The one year mortality data of 231 patients entering the hospital with acute myocardial infarction who did or did not undergo thrombolysis are presented. 49 patients (21.2%) received thrombolytic therapy. 31% were excluded from thrombolytic therapy because of age over 70 years, 29% because of the time lag since onset of symptoms (over 6 hours), 61% because of absent ECG criteria and 32% because of other contraindications. The one year mortality rate was significantly lower in patients undergoing thrombolysis (8.2%) versus patients without thrombolysis (20.3%, p less than 0.05). Mortality in patients without thrombolysis and age greater than 70 years was 23.6%, in patients with late entry 20.1%, in those excluded from thrombolytic therapy with missing ECG elevations 17.9% and in patients with contraindications 28%. If thrombolytic therapy was withheld due to age greater than 70 years or late entry only, mortality was high (33.3% and 38.5% respectively; p less than 0.02 versus lysis). This was not true for patients without significant ST elevation: to the contrary 12 of 42 patients without lysis (28.6%; p less than 0.02 versus lysed patients) and greater than or equal to 2 mm ST elevation irrespective of other exclusion criteria died. Since mortality in patients over 70 years of age or entering the hospital more than 6 hours after onset is of such magnitude (especially if there are ECG signs of ongoing ischemia), the risk-benefit ratio should be considered individually to ensure that these high-risk patients are not excluded a priori from thrombolytic therapy.