First and foremost, we would like to thank Lozano et al for their interest and comments on our study.1 Our objective was to analyze and compare the prognostic value of the absence or presence of stenosis on coronary angiography in patients with non–ST-segment elevation acute myocardial infarction.
On discharge, the current clinical guidelines on non-ST-segment elevation acute coronary syndrome recommend the use of risk scores, which offer prognostic information not only on new thrombotic events but also on overall mortality.2 As indicated by Lozano et al, overall mortality does not reflect the possible nonstenotic underlying coronary artery disease in patients without significant coronary lesions. However, from the clinical standpoint, the prognosis for death provides relevant clinical information for patients and their loved ones and helps to guide decisions on appropriate treatment and follow-up. This is of particular importance in patients without significant lesions who, in the absence of stenosis on coronary angiography, are usually considered to have a good prognosis. There is thus interest in emphasizing that long-term mortality in patients with non–ST-segment elevation acute myocardial infarction and no significant coronary lesions is similar to that in patients with significant coronary lesions.
To homogenize the sample and avoid a possible confounding effect of the inclusion of processes that could resemble non–ST-segment elevation acute coronary syndrome, our study included only patients with markers of myocardial damage within the range considered myocardial infarction. Thus, patients with unstable angina were excluded, unlike in the GYSCA registry.3 It is plausible that the more favorable prognosis for mortality in non–ST-segment elevation acute coronary syndrome in the GYSCA registry is the result of better prognosis in patients with unstable angina compared with those with non–ST-segment elevation acute myocardial infarction.
We used propensity score matching to ensure that patients with no significant coronary lesions and those with significant coronary lesions were comparable and to control for differences in baseline characteristics in the prognosis. The statistical analysis was conducted in the paired cohort with the intention of providing information on the prognostic value of the presence of stenosis in patients with non–ST-segment elevation acute myocardial infarction. The results should be interpreted in this context and are therefore not comparable with those from other populations.