R. Montone, G. Niccoli, G. Lanza
May 29, 2018
European heart journal
We appreciate the interest of Ciliberti et al. in our article about safety and prognostic relevance of invasive coronary provocative tests in patients presenting with myocardial infarction and non-obstructive coronary arteries (MINOCA). They raise concerns about the discharge therapy and the lack of any prognostic role of non-obstructive atherosclerosis. We agree that an optimal medical therapy might improve prognosis in MINOCA. However, no controlled trial has hitherto been conducted regarding pharmacological therapy in MINOCA. Recent retrospective data have suggested that statins, beta-blockers and renin–angiotensin– aldosterone (RAA) system antagonists might have favourable effects in MINOCA patients. However, besides being uncontrolled, this study included the whole heterogeneous population of MINOCA, and it is unclear whether the results might entirely be applied to MINOCA caused by vasomotor mechanisms. Indeed, the beneficial effects of statins in vasospastic angina patients are controversial, and no beneficial effects are expected from beta-blockers and RAA system antagonists. Importantly, in our study calcium-antagonist discontinuation during follow-up was a relevant prognostic variable, whereas no relation with clinical outcome was found with the use of other drugs. We have also shown that non-obstructive atherosclerosis was more frequently found in patients with a positive response to provocative tests. However, non-obstructive atherosclerosis failed to predict events at follow-up, whereas a positive test response was a significant independent predictor of events. This suggests that nonobstructive atherosclerosis may predispose to the occurrence of functional coronary alterations, but an impaired vasoreactivity only may portend a worse prognosis in the highly selected subgroup of MINOCA patients included in our study, which does not exclude, however, a prognostic role of non-obstructive atherosclerosis in the global unselected MINOCA population. In conclusion, future studies are warranted in order to establish the optimal medical treatment of MINOCA patients. Talking about the ‘MINOCA population’ as a whole, however, is likely misleading. MINOCA patients constitute a heterogeneous population and, therefore, future clinical trials should include patients with a common pathophysiologic mechanism in order to achieve results successfully applicable in specific subgroups.