MINOCA due to vasospasm compared to other mechanisms: patients characteristics, evolution and prognosis
Authors: Martin Munoz M , Izquierdo Coronel B , Fraile Sanz A , Alvarez Bello M , Perela Alvarez C , Nieto Ibanez D , Olsen Rodriguez R , Abad Romero R , Rodriguez Montes P , Gil Mancebo N , Mata Caballero R , Lopez Pais J , Espinosa Pascual M J , Awamleh Garcia P , Alonso Martin J J 
Published: November 2023

Abstract

Introduction
coronary vasospasm is a common cause of MINOCA (myocardial infarction with non-obstructive coronary arteries). The aim of this study is to compare characteristics and prognosis of patients (pts) with MINOCA due to vasospasm (MINOCA-V) vs those with MINOCA due to other causes (MINOCA-O).

Methods
we included all MINOCA pts between January 2015-December 2022. The definitions of MINOCA and vasospasm were based on European Clinical Guidelines. The diagnosis of vasospasm was made in the cath lab or with non-invasive bedside tests (ergonovine). The follow-up analysis included major adverse cardiovascular events (MACE: death from any cause, cardiovascular readmission, reinfarction and stroke). The median follow-up was 59.5 months [36-75].

Results
there were a total of 120 MINOCA pts, of which 19 (16%) were MINOCA-V and 101 (84%) MINOCA-O (embolism, dissection, type II infarction, unknown). Regarding the clinical profile of MINOCA-V, they were fewer women (21 vs 49% p=0.03), younger (mean age 56±11 vs 63±15 p=0.03) and more smokers (78.9 vs 50.5% p=0.02). There were no significant differences in cocaine use (7.7 vs 5.5% p=0.75) or other baseline characteristics (Table 1). Not only there was a higher percentage of pts with ST elevation at admission in the vasospasm group (53 vs 12% p&lt;0.01), but also they presented with a higher elevation of biochemical markers of myocardial damage (MMD), both troponin (125.11±203.8 vs 609.48±1661.2 ng/L,p&lt;0.01) and CK (201±272.4 vs 338.75±384.3 U/L p=0.01). There were no significant differences in renal function (Cr 1.4±1.8 vs 1.1±1.5mg/dL p=0.15) and cholesterol levels (163.05±48 vs 172.6±65.7mg/dL p=0.99). The use of magnetic resonance imaging to complete diagnosis did not differ between both groups (26vs37% p=0.34), although it was more effective when approaching the etiology in MINOCA-O (0 vs 18%, p=0.04). The duration of admission was similar between both groups (6±4 days in MINOCA-V vs 5±4 in MINOCA-O, p=0.78). The treatment at discharge was different, being greater the use of nitrates (53vs10% p&lt;0.01) and calcium antagonists (CA), both not dyhidropyridines (53 vs 7% p&lt;0.01) and dihydropyridines (53 vs23% p=0.01) in MINOCA-V and less that of beta-blockers (BB) (0 vs 62% p&lt;0.01) and acetylsalicylic acid (ASA) (32vs73% p&lt;0.01).
During follow-up, the evolution was similar in terms of mortality (HR 1.81 IC95%[0.33-10] p=0.2) and MACE (HR 1.76 IC95%[0.69-4.51] p=0.17). No differences were found in cardiovascular readmissions (HR 1.04 IC95%[0.35-3.07] p=0.29), stroke (no cases in both groups) and reinfarction (HR 1.3 IC95%[0.25-6.81] p=0.57).

Conclusion
we conclude that pts with MINOCA-V are more likely to be male, younger and smokers than MINOCA-O. They usually present with ST elevation and increased elevation of MMD. Treatment at discharge is different: with greater use of nitrates and CA and lower ASA and BB. The prognosis is similar in both groups with no significant differences in mortality or MACE.