Prevalence, Risk Factors, and Outcome of Myocardial Infarction with Angiographically Normal and Near-Normal Coronary Arteries: A Systematic Review and Meta-Analysis

Context: Coronary artery diseases are mostly detected using angiographic methods demonstrating arteries status. Nevertheless, Myocardial Infarction (MI)may occur in the presence of angiographically normal coronary arteries.Therefore, this study aimed to investigate the prevalence of MI with normalangiography and its possible etiologiesin a systematic review.Evidence Acquisition: In this meta-analysis, the required data were collectedfrom PubMed, Science Direct, Google Scholar, Scopus, Magiran, ScientificInformation Database, and Medlib databases using the following keywords: coronary angiograph , normal coronary arteries , near-normal coronaryarteries , heart diseases , coronary artery disease , coronary disease , cardiac troponin I , Myocardial infarction , risk factor , prevalence , outcome , and their Persian equivalents. Then, Comprehensive Meta-Analysissoftware, version 2 using randomized model was employed to determine theprevalence of each complication and perform the meta-analysis. P values lessthan 0.05 were considered to be statistically significant.Results: Totally, 20 studies including 139957 patients were entered into theanalysis.The patients’ mean age was 47.62 ± 6.63 years and 64.4% of the patients weremale. The prevalence of MI with normal or near-normal coronary arteries was3.5% (CI = 95%, min = 2.2%, and max = 5.7%). Additionally, smoking andfamily history of cardiovascular diseases were the most important risk factors.The results showed no significant difference between MIs with normalangiography and 1- or 2-vessel involvement regarding the frequency of major adverse cardiac events (5.4% vs. 7.3%, P = 0.32). However, a significant difference was found between the patients with normal angiography and those with 3-vessel involvement in this regard (5.4% vs. 20.2%, P < 0.001).Conclusions: Although angiographic studies are required to assess the underlying etiology of MI, physicians facing patients presenting with the clinical features of MI in presence of normal or near-normal coronary arteries should consider the prevalence and risk factors of MI with normal or near-normal coronary arteries