BACKGROUND AND AIM
Acute coronary syndrome (ACS) with non-critical coronary arteries represents a major diagnostic, therapeutic and prognostic challenge for clinicians. The aim was to compare clinical-anamnestic characteristics and assess the prognosis of three cohorts with ACS with non-critical coronary arteries i.e. Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA), type 2 myocardial infarction (MI) and Takotsubo syndrome (TTS).
METHODS
In this single center observational study, 18223 patients who underwent coronary angiography between 2005 and 2022 were retrospectively analyzed. The final cohort included 676 patients with initial presentation as NSTEMI (301 MINOCA, 237 type 2 MI and 138 TTS).
RESULTS
The median age was 68±11, with the TTS population being the oldest (72±10, 0.01), presenting greater hypotension (0.01), tachycardia (0.01), and fewer cardiovascular risk factors, such as diabetes (0.01) and hypertension (0.01). The TTS cohort had worse LVEF on admission (0.01) and on discharge (0.01) (Fig. 1). At Kaplan-Meier analysis, patients with type 2 MI were more prone to the composite endpoint, while the TTS group was less likely (0.01) (Fig. 2). In the overall cohort, ACEi/ARB therapy on admission was an independent predictor of the composite endpoint (HR: 1.58;p=0.01), while dual antiplatelet therapy (DAPT) (HR: 0.59;p=0.01) and statin (HR: 0.71;p=0.03) at discharge were protective. After stratification according to diagnosis, ACEi/ARB therapy remained a negative predictor only in the type 2 MI cohort (HR: 2.03;p=0.01) as well as beta-blocker therapy at admission in TTS (HR: 2.97;p=0.03), while statin therapy remained protective in the MINOCA (HR: 0.51;p=0.01) and DAPT therapy in the TTS group (HR: 0.21;p=0.04) at discharge. Although a substantial number of patients with all three diagnoses achieved the endpoint, the multivariable Cox regression analysis indicated that type 2 MI, in addition to older age, male gender, worse LVEF, and anemia, is an independent factor for worse outcomes (Fig. 3).
CONCLUSIONS
Among all cohorts, T2 MI were associated with worse outcome. The use of DAPT in TTS and Statins in the MINOCA group showed a protective role. Since the TTS population was more compromised, BB use in the ADHF phase of TTS could predict a poorer outcome as much as ACEI/ARB use at admission could be a marker of greater early LV impairment of the T2 MI cohort, which was an independent predictor for worst outcome.
