The prognosis evaluation of guideline-directed medical therapy for type 2 acute myocardial infarction patients with acute respiratory failure

Abstract Backgrounds Type 2 myocardial infarction (T2MI) arises from an imbalance between myocardial oxygen supply and demand during acute illness such as tachyarrhythmia, hypoxia, or hypotension without acute atherothrombosis. The efficacy of guideline-directed medical therapy (GDMT) in T2MI complicated by acute respiratory failure remains uncertain. Purposes This study was aimed to assess the impact of GDMT (including dual antiplatelet therapy, statins and β-blockers) on the prognosis of patients with T2MI and acute respiratory failure. Methods The data for this study were derived from a retrospective cohort of patients admitted to and discharged from 72 secondary and tertiary hospitals between 2010 and 2023. Inclusion criteria included patients with a discharge diagnosis of T2MI and acute respiratory failure. GDMT was defined according to the ACC/AHA Class I recommendations. Patients were divided into GDMT and N-GDMT groups, with differences in clinical characteristics adjusted using propensity score matching (PSM). Primary outcome indicators were major adverse cardiac and cerebrovascular events (MACCE), while secondary outcome indicators included in-hospital mortality, cardiac mortality, non-lethal myocardial infarction, recurrent ischemic stroke, bleeding events and revascularization. Results This study comprised 898 patients in the GDMT group and 3,777 in the N-GDMT group, resulting in 888 matched pairs after PSM. Baseline data showed that patients in the GDMT group had a higher burden of pre-existing comorbidities. In terms of treatment, the GDMT group had a higher proportion of patients undergoing Percutaneous Coronary Intervention (PCI) (4.84% vs. 1.80%, p= 0.001). In-hospital mortality was significantly lower in the GDMT group (12.4% vs. 26.4%, p< 0.001).Over amedian follow-up of 1,304 days, the incidence of MACCE within 1 month was significantly lower in the GDMT group (23.1% vs. 41.3%, p< 0.001). Furthermore, the GDMT group exhibited lower all-cause mortality (52.4% vs. 60.1%, p＜0.01) and cardiac mortality (41.3% vs. 50.3%, p< 0.001) compared to the N-GDMT group, with higher rates of revascularization (3.15% vs. 1.24%, p＜0.01). There were no statistically significant differences in the incidence of bleeding BARC3 (0.45% vs. 0.45%, p=1), recurrent non-lethal myocardial infarction (0.23% vs. 0%, p =0.5) and recurrent stroke (1.46% vs. 0.79%, p =0.261). GDMT at discharge was associated with a lower risk of MACCE in unadjusted analysis (HR=0.51, 95%CI= 0.44-0.59, p＜0.01) and after adjusting for age, gender, Killip classification and comorbidities in multivariate Coxregression analysis (aHR = 0.49, 95%CI= 0.41-0.58). Conclusions Adherence to GDMT was associated with a lower incidence of MACCE during 1-month follow-up, suggesting the importance of GDMT in this patient population.Clinical characteristics of patients