- Type 2 Myocardial Infarction (T2MI) is increasingly recognized as clinically distinct, one of 5 MI types
- T2MI is common, frequently recurrent and linked to poor prognosis similar to T1MI
- Patients at risk of developing T2MI may now be identified by a suite of risk factors
- Further studies are needed to design the multidisciplinary care T2MI patients require
Type 2 myocardial infarction (T2MI) is defined as myocardial necrosis attributable to blood supply/demand mismatch. It is clinically distinct and is one of 5 MI types. T2MI is increasingly recognized due to the widespread use of increasingly sensitive troponin assays, according to a Massachusetts General Hospital study published in Circulation.
Based on the study of patients undergoing coronary or peripheral angiography for a broad range of indications, T2MI was found to be “common and associated with poor prognosis,’’ says lead author James L. Januzzi, MD, cardiologist at Mass General.
But because a defined treatment strategy has not yet been elaborated, patients are at risk of being treated with less urgency than T1MI. “Studies evaluating treatment strategies for management of T2MI are needed,” says Dr. Januzzi.
In one of the largest systematic surveys of T2MI frequency, implications and risk factors a Mass General team studied 1,251 patients at a single center who were undergoing coronary or peripheral angiography with or without percutaneous intervention, and who received follow-up for a major adverse cardiovascular event (MACE). These patients were evaluated for frequency and implications. During the 1,234 days of follow-up, 16.5% (206) patients had at least one MI. Within this MI group, 73.8% (152) had at least 1 incidence of T2MI. Most study participants experiencing more than a single MI had subsequent T2MI, regardless of the index MI.
In contrast, it was rare for study participants who experienced an initial T2MI to subsequently have other types of MI.
Risk Factors Identified
In comparison with patients without T2MI, study participants who subsequently had an incident of T2MI were older, had more complex medical histories with prevalent comorbidities (including both cardiovascular and non-cardiovascular diagnoses) and were treated more extensively for cardiometabolic diseases.
Patients having an incident of T2MI after enrollment were also more likely to have higher baseline myeloperoxidase, N-terminal pro-B-type natriuretic peptides and cystatin C concentrations, and high-sensitivity to troponin I.
A significant proportion of patients with T2MI had a history of prior coronary artery disease and prior revascularization procedures, whether with stents or bypass surgery.
Overall, study results suggest those with T2MI represent a morbid population in need of multidisciplinary care and further study to reduce risk.
Refer a patient to the Corrigan Minehan Heart Center