1-year mortality elevated after procedural/spontaneous myocardial infarction

A significantly higher 1-year mortality is seen following procedural myocardial infarction (pMI) and spontaneous MI (spMI) with troponin peak >35x the upper reference level (URL), reports a study. On the other hand, only spMI demonstrates a significant influence on mortality for troponin levels ≤35x.

In total, 10,707 patients underwent percutaneous coronary intervention (PCI) from 2012 to 2020, of whom 8,515 presented with chronic coronary syndrome (CCS) and 2,192 with spMI. Among patients with CCS, 913 (10.7 percent) had pMI.

Troponin peaks >1-5×, >5-35×, and >35× the URL were noted in 53 percent, 41 percent, and 6 percent of pMI patients, and in 24 percent, 38 percent, and 37 percent of spMI patients, respectively.

At 1 year, mortality rates were increased after pMI (7.7 percent; adjusted hazard ratio [aHR], 4.40, 95 percent confidence interval [CI], 1.59‒12.2) and after spMI (8.5 percent; aHR, 7.57, 95 percent CI, 5.44‒10.5) with troponin peak >35x the URL relative to those without MI (1.4 percent). Additionally, there was high mortality following spMI with troponin peak >1-5× or >5-35× the URL.

This study included patients with CCS and baseline troponin ≤1× the URL or with acute spMI who underwent PCI. PMI was characterized by post-PCI troponin increase >1x the URL in CCS patients, while spMI consisted of any acute coronary syndrome with elevated troponin.

The researchers evaluated the 1-year risk of all-cause death after pMI and spMI across three strata of troponin elevation (>1-5×, >5-35×, and >35× the URL). CCS patients with post-PCI troponin ≤1× the URL served as reference. Finally, the Architect methodology was used to measure conventional troponin I.