Research Myocardial Infarction After Hip Fracture Repair

We read with interest the article of Huddleston and colleagues on the incidence of postoperative myocardial infarction (POMI) after hip fracture repair (HFR).1 We fully agree with their conclusion that “the ACC/AHA preoperative cardiac evaluation guideline for major orthopedic surgery underestimates the incidence of MI after hip fracture repair,” but we think that the use of the universal definition of myocardial infarction (UDMI) is worrisome, because it underestimates the incidence itself and the severity. The incidence is very likely underestimated because all studies addressing POMI through systematic detection (Holter monitoring or systematic troponin dosage) show that one-third of POMI are symptomatic.2 Accordingly, Beattie and colleagues have recently shown that a detection policy based only on the physician's discretion allows detection of only one-third of POMI.3 This underdetection may lead to an underestimation of severity in the HFR setting, because the “POMI population” is compared with a population of individuals with and without POMI, and in the HFR setting, the described incidence of POMI varies between 27% and 50%,4 so the control group could include 26–40% of undiagnosed POMI. Furthermore, the post hoc analysis of the Perioperative Ischemic Evaluation Study and the Vascular Events in Noncardiac Surgery Patients Cohort Evaluation Study have shown that asymptomatic POMI leads to the same outcome as symptomatic POMI.5, 6 Thus, we believe that the authors failed, based upon their biased explanation and contrary to most available data,7 to find a relationship between POMI and postoperative outcomes. Nevertheless, myocardial ischemia after HFR is a major health burden, as Rosencher and colleagues, who found in a cohort of 6,860 individuals that cardiovascular disease was the most frequent cause of death at 6 months, clearly showed. The onset of this morbidity seems to occur early in the clinical course because all published studies of the use of postoperative troponin I cardiac test after HFR show a correlation with early and late cardiac outcome.4 Thus, not only preventing but also detecting and treating POMI after HFR may be of paramount interest in reducing mortality, and measurement of troponin levels could be of great help with the task itself. In addition, troponin measurements are easy to obtain and are reliable markers of cardiac morbidity correlated with in-hospital and late morbidity to measure the effectiveness of preventive strategies. This is presently established for asymptomatic cardiac complications with high troponin levels and variations in the incidence of high troponin levels in a specific population, which can also be used as a measurement of quality of care.8 This may lead to specific interventions in perioperative care that some authors have identified as a critical part of an individual's outcome.9, 10 Conflict of Interest: The authors have no conflict of interest to disclose. Author Contributions: All authors contributed to the writing of this paper. Sponsor's Role: None.