Aims: To evaluate the effect of thrombolysis on mortality and its causes in older patients with acute myocardial infarction (AMI).
Methods and results: An analysis of 706 consecutive patients > or =75 years old with a first AMI enrolled in the PPRIMM75 registry showed that although there were important differences in baseline characteristics among patients treated with thrombolysis, primary angioplasty (PA) and those who did not receive reperfusion therapy, 30 day mortality did not differ (29, 25, and 32%, respectively). The main cause of death in patients treated with thrombolysis was cardiac rupture (54%), whereas most of the other patients died in cardiogenic shock. Patients who received thrombolysis had a higher (P<0.0001) incidence of free wall rupture (FWR) (17.1%) compared with those who did not receive reperfusion therapy (7.9%) or who underwent PA (4.9%). By multivariable analysis, patients treated with thrombolytic therapy (TT) showed an excess risk of FWR (OR, 3.62; 95% CI, 1.79-7.33), a hazard not observed in patients who underwent PA. When compared with patients who did not receive reperfusion therapy, the odds ratio of 30 day mortality was 1.07 (95% CI, 0.65-1.76) for patients treated with thrombolysis and 0.78 (95% CI, 0.45-1.34) for those who underwent PA. The figures for 24 month mortality were 0.78 (95% CI, 0.65-1.76) and 0.67 (95% CI, 0.28-0.81), respectively.
Conclusion: Treatment of first AMI with TT increases the risk of FWR in very old patients, a risk not observed in patients treated with PA.