Types of Myocardial Infarction Among Human Immunodeficiency Virus–Infected Individuals in the United States

Abstract

Importance The Universal Definition of Myocardial Infarction divides myocardial infarctions into different types. Type 1 myocardial infarctions result spontaneously from atherosclerotic plaque instability, whereas Type 2 myocardial infarctions occur in the setting of oxygen demand/supply mismatch such as with severe hypotension. Type 2 myocardial infarctions are uncommon in the general population but the frequency of Type 2 myocardial infarctions in HIV-infected individuals is unknown. Objective To characterize myocardial infarctions including type; identify causes for Type 2 myocardial infarctions, and compare demographic and clinical characteristics among HIV-infected individuals with Type 1 vs. Type 2 myocardial infarctions. Setting/Design Longitudinal HIV clinical care cohort at 6 U.S. sites. Events Potential myocardial infarctions from 1996–2014 were identified in the centralized data repository using diagnoses and cardiac biomarkers. Sites assembled de-identified packets including physician notes, ECGs, procedure and clinical laboratory results. Two physician experts adjudicated each event, categorizing each definite/probable myocardial infarction as a Type 1 or Type 2 myocardial infarction, and identifying Type 2 myocardial infarction causes. Results Among 571 definite/probable myocardial infarctions, 288 (50%) were Type 2; sepsis and recent cocaine/crack use were the most common causes (35% and 14% of Type 2 myocardial infarctions, respectively). Individuals with Type 2 myocardial infarctions were younger on average and had lower CD4 cell counts, lipid levels, and Framingham risk scores than those with Type 1 myocardial infarctions. Limitations Missing events or ascertainment bias is always a concern although we used both diagnoses and biomarkers to minimize this as much as possible. In addition, although we used a standardized approach with multiple expert adjudicators, distinguishing MI type with certainty can be difficult and there may be some misclassification of type. Conclusions/Relevance Approximately half of myocardial infarctions among HIV-infected individuals were Type 2. Type 2 myocardial infarctions were caused by heterogeneous clinical conditions including sepsis and cocaine/crack use. Demographic characteristics and cardiovascular risk factors among those with Type 1 and Type 2 myocardial infarctions differed, suggesting the need to specifically consider type among HIV-infected individuals to further understand myocardial infarction outcomes and to guide prevention and treatment.

Increased Risk of Myocardial Infarction in HIV-Infected Individuals in North America Compared With the General Population

“…Distinguishing between types is important because T2MIs result from an imbalance of myocardial oxygen supply and demand caused by a diverse set of clinical conditions, including sepsis and cocaine-induced vasospasm 27 , whereas T1MIs are due to spontaneous atherosclerotic plaque rupture, erosion, or dissection with associated intraluminal thrombus 26 . We have shown 28 that T2MIs may account for a greater proportion of MIs among HIV-infected individuals as compared with what is seen in the general population due in part to the high prevalence of illicit drug use 29 and concurrent infections among HIV-infected individuals.…”

Epidemiology of ischemic heart disease in HIV

“…In a large study from the Centers for AIDS Research Network of Integrated Clinical Systems Cohort (CNICS), MI events were divided evenly between type 1 (atherosclerotic plaque instability/rupture) and type 2 (oxygen supply/demand mismatch), with type 2 MIs more common among patients <40 years, with lower CD4 counts, and with lower traditional CVD risk. 30 Earlier data demonstrated HIV-infected individuals with acute coronary syndromes (ACS) more likely to have single-vessel disease and high restenosis rates. 31 A recent study found HIV-infected individuals presenting with ACS to have a lower overall burden of coronary plaque compared with matched control patients, 32 but another found no difference in rates of severe coronary artery disease in HIV-infected versus matched control patients undergoing coronary angiography.…”

Editorial Commentary: Clinical management of cardiovascular disease in HIV-infected patients

“…Including the assessment of subclinical atherosclerosis by measuring carotid artery intima-media thickness via ultrasound 11 or assessment of plaque features by coronary computed tomography angiography 12 will greatly improve risk stratification models. Further, in HIV+ patients with MI, it is important to diagnose specific types of MI as type 1 (caused by atherosclerosis) and type 2 (caused by bacteremia and recent use of recreational drugs) because they may require different treatment approaches 13 . Approximately half of myocardial infarction (MI) in HIV+ patients were type 2 MIs, which is higher than those in HIV negative patients 13 .…”

“…Further, in HIV+ patients with MI, it is important to diagnose specific types of MI as type 1 (caused by atherosclerosis) and type 2 (caused by bacteremia and recent use of recreational drugs) because they may require different treatment approaches 13 . Approximately half of myocardial infarction (MI) in HIV+ patients were type 2 MIs, which is higher than those in HIV negative patients 13 . Taken together, general as well as specific management approaches will help better diagnosis, prevent and treat CVD in HIV+ patients.…”