A ‘mess’ of a diagnosis: Is it type 2 MI or a nonischemic imposter?
The unsettled role of drug therapy
With their often-complicated clinical profile, patients with type 2 MI or nonischemic myocardial injury tend to be medically undertreated, yet there is observational evidence they can benefit from familiar drug therapies.
In the previously noted cohort study of 3,800 younger patients with one of the three forms of myocardial injury, less than half of patients with type 2 MI received any form of CAD secondary prevention therapy at discharge, the researchers, with first author Avinainder Singh, MD, from Yale University, New Haven, Conn, wrote.
The finding, consistent with Dr. Newby’s study from 2018, suggests that “categorizing the type of MI in young subjects might inform long-term cardiovascular prognosis,” and “emphasizes the need to identify and implement secondary prevention strategies to mitigate the high rate of cardiovascular death in patients with type 2 MI,” they concluded.
Further, outcomes varied with the number of discharge CV meds in an older cohort of patients with myocardial injury. Those with type 2 MI or acute or chronic nonischemic myocardial injury were far less likely than patients with type 1 MI to be prescribed guideline-based drugs. Survival was greater for those on two or three classes of CV medications, compared with one or none, in patients with acute or chronic nonischemic injury.
The investigators urged that patients with nonischemic myocardial injury or type 2 MI “be treated with cardiovascular medication to a larger degree than what is done today.”
When there is documented CAD in patients with type 2 MI, “it would be reasonable to suggest that preventative secondary prevention approaches, such as such lipid-reduction therapy or aspirin, would be beneficial,” Dr. Sandoval said. “But the reality is, there are no randomized trials, there are no prospective studies. ACT-2 is one of the few and early studies that’s really trying to address this.”
“The great majority of these people are not going to the cath lab, but when they do, there seems to be a signal of potential benefit,” Dr. Januzzi said. “For someone with a type 2 MI, it’s quite possible revascularization might help. Then more long-term treatment with medications that are proven in randomized trials to reduce risk would be a very plausible intervention.”
“We’ve actually proposed a number of potential therapeutic interventions to explore, both in people with type 2 MI and in people with injury without MI,” he said. “They might include sodium glucose cotransporter 2 inhibitors. They might include antithrombotic therapy or more aggressive lipid lowering, possibly for the pleiotropic effects rather than the effects on atherosclerosis.”
Any such therapies that prove successful in well-designed trials could well earn both type 2 MI and nonischemic myocardial injury, neglected as disorders in their own right, the kind of respect in clinical care pathways that they likely deserve.
Dr. Newby has disclosed receiving consulting fees or honoraria from Eli Lilly, Roche, Toshiba, Jansen, Reckitt Benckiser Pharmaceuticals, Pfizer, AstraZeneca, Bristol-Myers Squibb, GlaxoSmithKline, CellProthera, and Oncoarendi; and conducting research or receiving grants from Pfizer, AstraZeneca, Bristol-Myers Squibb, GlaxoSmithKline, Merck, Boehringer Ingelheim, and Inositec. Sandoval reports serving on an advisory board and as a speaker for Abbott Diagnostics and on an advisory board for Roche Diagnostics. Dr. Januzzi has disclosed receiving grant support from Novartis, Applied Therapeutics, and Innolife; consulting for Abbott Diagnostics, Janssen, Novartis, Quidel, and Roche Diagnostics; and serving on endpoint committees or data safety monitoring boards for trials supported by Abbott, AbbVie, Amgen, CVRx, Janssen, MyoKardia, and Takeda. Dr. Chew has reported receiving grants from AstraZeneca and Edwards Life Sciences. ACT-2 is sponsored by the National Medical and Health Research Council of Australia.
A version of this article first appeared on Medscape.com.