The Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) Classification System

Abstract

Background Current classification schemes for acute myocardial infarction (AMI) may not accommodate the breadth of clinical phenotypes in young women. Methods and Results We developed a novel taxonomy among young adults (<55 years) with AMI enrolled in the Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) study. We first classified a subset of patients (n=600) according to the Third Universal Definition of MI using a structured abstraction tool. There was heterogeneity within Type 2 AMI, and 54 patients (9%; including 51 of 412 women) were unclassified. Using an inductive approach, we iteratively grouped patients with shared clinical characteristics, with the aims of developing a more inclusive taxonomy that could distinguish unique clinical phenotypes. The final VIRGO taxonomy classified 2,802 study participants as: Class 1, plaque-mediated culprit lesion (82.5% of women; 94.9% of men); Class 2, obstructive coronary artery disease with supply-demand mismatch (2a: 1.4% women; 0.9% men;) and without supply-demand mismatch (2b: 2.4% women; 1.1% men); Class 3, non-obstructive coronary artery disease with supply-demand mismatch (3a: 4.3% women; 0.8% men) and without supply-demand mismatch (3b: 7.0% women; 1.9% men); Class 4, other identifiable mechanism: spontaneous dissection; vasospasm; embolism (1.5% women; 0.2% men); and Class 5, undetermined classification (0.8% women; 0.2% men). Conclusions Approximately 1 in 8 young women with AMI are unclassified by the Universal Definition of MI. We propose a more inclusive taxonomy that could serve as a framework for understanding biological disease mechanisms, therapeutic efficacy and prognosis in this population.

Outcomes with type 2 myocardial infarction compared with non-ischaemic myocardial injury

“…However, the distinction between type 2 MI and NIMI (the latter having additional implications for the psychosocial environment of the patient) has not led to the development of rigorously tested therapeutic strategies or procedures aimed at improving their mid-term or short-term prognosis. For this reason, in agreement with other authors,29 30 we believe that a review of the current nomenclature of MI is essential to ensuring the homogeneity of clinical studies and thus a thoughtful understanding of this clinical entity.…”

Presentation, Clinical Profile, and Prognosis of Young Patients With Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA): Results From the VIRGO Study

“…VIRGO was a prospective observational study of patients aged 18 to 55 years presenting with an AMI in 103 geographically diverse hospitals from August 2008 to January 2012 using a strict 2:1 enrollment ratio of women to men. AMI was defined as (1) an increase in cardiac biomarkers (troponin I or T or creatine kinase‐MB) with at least 1 value >99th percentile of the upper reference limit within 24 hours of admission and (2) supporting evidence of acute myocardial ischemia, including symptoms or ECG changes 18. Patients with elevated cardiac markers due to a complication of elective coronary revascularization, presumed myocarditis, or takotsubo were not eligible for VIRGO.…”

“…We used the previously published VIRGO taxonomy that classified patients into 5 phenotypes 18. Briefly, class I included patients with plaque‐mediated obstructive culprit lesions who underwent revascularization; class II included patients with obstructive coronary artery disease (≥50%) but without evident plaque rupture/thrombosis; class III included patients with nonobstructive coronary artery disease (<50%); class IV included patients with a nonplaque mechanism identified for ischemia by the primary treatment team, including coronary artery vasospasm (relieved by intracoronary nitroglycerin), SCAD (regardless of degree of stenosis), and coronary artery embolization; and class V included patients with undetermined classification.…”

“…The VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study, the largest prospective multicenter study that enrolled young adults under age 55 years with a diagnosis of AMI and had an oversampling of women,17 provides an ideal opportunity to look more carefully at MINOCA. One in 8 young women in VIRGO had no evidence of plaque rupture or thrombosis, allowing pathophysiologically driven insight into the study of ischemic MINOCA 18. Accordingly, we studied this sample to better characterize the presentation, sociodemographic and psychosocial data, clinical characteristics, sex‐specific factors (eg, perimenopausal and peripartum status), and outcomes in MINOCA versus MI‐CAD patients and among MINOCA patients by phenotypic mechanism and sex.…”

Acute Myocardial Infarction in Women

“…Approximately 1 of 8 young women with AMI in the VIRGO study did not fit in the current classification schemes for AMI, and as a result, the authors have proposed a new, more inclusive taxonomy that may provide a framework for improved understanding and investigation into risk factors, treatment strategies, and outcomes in young women. 113 For now, it is intriguing that the underlying mechanism of AMI varies by sex, with implications for treatment, yet more scientific investigation is needed in the realm.…”