Perioperative Myocardial Ischemia: Troponin Monitoring,Cost-effectiveness, Insights Into Pathophysiology

Background: Despite preoperative screening, technical improvements and increased patient monitoring, perioperative myocardial infarction (PMI) remains the first cause of morbidity and mortality within 30 days after surgery. Moreover, the available evidence indicates worrying rise of risk in postoperative patients with only elevated troponins reflecting cardiac injury, but without a conventional clinical diagnosis of myocardial infarction according to current definition. Worldwide, annually approximately 300 million adults undergo major non cardiac surgery and 10 million of them are estimated to suffer a myocardial injury after non-cardiac surgery (MINS), defined as a prognostically relevant increase of a troponin T peak of 0.03 ng/ml or greater. Many of the patients with MINS does not fulfill the universal definition of myocardial infarction, rarely experience ischemic symptoms and their prognosis is very poor (1 out of 10 die at 30 days).Troponin levels needed to be monitored in order to MINS diagnose and high sensitive cardiac troponin T assays are currently the most frequently used. Methods: Patients with high cardiovascular risk undergoing major non-cardiac surgery will be selected from the daily surgical program during a two years period Three determinations of hs-cTnT for each patient will be obtained. The proportion of patients with MINS and pre- and post-operative thresholds of hs-cTnT that would be prognostically relevant will be determined. The cost-effectiveness analysis of hs-cTnT monitoring compared with usual care will be undertaken. Finally using computed tomography angiography (CTA) and cardiac magnetic resonance imaging (MRI) pathophysiology of MINS will be determined, whether is due to plaque rupture, supply-demand mismatch, non-ischemic cardiac cause or non-cardiac cause. Discussion: The study will evaluate the feasibility and impact of implementing the hs-cTnT monitoring program in the Hospital de la Santa Creu i Sant Pau of Barcelona, as well