Predictors of the Use of Mineralocorticoid Receptor Antagonists in Patients With Left Ventricular Dysfunction Post-ST-Segment-Elevation Myocardial Infarction

Advantages of long-term combination pharmacotherapy with a beta-blocker and eplerenone in patients with ST-segment elevation acute coronary syndrome

Aim. To conduct a comparative analysis of the effect of long-term pharmacotherapy (12 months) using a β-blocker (nebivolol) and its combination with eplerenone in patients after ST-segment elevation acute coronary syndrome (STE-ACS) with heart failure with mildly reduced ejection fraction (EF) (HFmrEF) on the structural and functional cardiac parameters.

Material and methods. We examined 130 patients with STE-ACS and HFmrEF after successful myocardial revascularization by percutaneous coronary intervention. The mean age of patients was 53,6 [46;57] years. Ten patients withdrew from the study due to personal reasons. Subsequently, patients were randomly divided into 2 treatment groups as follows: 60 patients received nebivolol; 60 patients received nebivolol and eplerenone. Patients were examined at two stages: 1st day of the disease before PCI and 12 months later. All patients underwent a clinical examination, echocardiography, followed by assessment of left ventricular (LV) EF, LV end-diastolic volume index (EDVI), LV endsystolic volume index (ESVI), LV myocardial index (LVMI), LV wall motion score index (WMSI), the ratio of peak early diastolic flow over peak late diastolic flow (E/A), the ratio of early diastolic transmitral flow velocity to the mitral annular velocity (E/e´).

Results. Twelve-month pharmacotherapy with nebivolol in patients after STE-ACS showed an increase in LVEF by 7,2% (p<0,05), a decrease in WMSI by 13,0% (p<0,05), an increase in the E/A ratio by 11,1% (р<0,05), decrease in the E/e’ ratio by 7,2% (р<0,05). LV EDVI increased by 4,6% (p>0,05). Twelve-month combined pharmacotherapy with nebivolol and eplerenone showed an increase in LVEF by 16,0% (p<0,01), a decrease in LV ESVI by 17,9% (p<0,05), and a decrease in WMSI by 26,7% (p<0,01), LVMI — by 23,8% (р<0,01). At the same time, LV EDVI decreased by 0,7% (p>0,05). The E/A ratio increased significantly by 22,2% (<0,01), E/e’ decreased by 29,6% (р<0,01). Comparative analysis also found that combination therapy had a more pronounced positive effect on LVEF (p<0,05), ESVI (p<0,05), WMSI (p<0,05), LVMI (p<0,01), as well as diastolic function in the form of a significant increase in E/A (p<0,05) and E/e’ (p<0,01), which recovered to normal values.

Conclusion. The advantages of long-term combination pharmacotherapy of nebivolol and eplerenone in HFmrEF patients after STE-ACS on both structural and functional cardiac parameters were established.

New Perspectives on Sex Steroid and Mineralocorticoid Receptor Signaling in Cardiac Ischemic Injury

The global burden of ischemic heart disease is burgeoning for both men and women. Although advances have been made, the need for new sex-specific therapies targeting key differences in cardiovascular disease outcomes in men and women remains. Mineralocorticoid receptor directed treatments have been successfully used for blood pressure control and heart failure management and represent a potentially valuable therapeutic option for ischemic cardiac events. Clinical and experimental data indicate that mineralocorticoid excess or inappropriate mineralocorticoid receptor (MR) activation exacerbates ischemic damage, and many of the intracellular response pathways activated in ischemia and subsequent reperfusion are regulated by MR. In experimental contexts, where MR are abrogated genetically or mineralocorticoid signaling is suppressed pharmacologically, ischemic injury is alleviated, and reperfusion recovery is enhanced. In the chronic setting, mineralocorticoid signaling induces fibrosis, oxidative stress, and inflammation, which can predispose to ischemic events and exacerbate post-myocardial infarct pathologies. Whilst a range of cardiac cell types are involved in mineralocorticoid-mediated regulation of cardiac function, cardiomyocyte-specific MR signaling pathways are key. Selective inhibition of cardiomyocyte MR signaling improves electromechanical resilience during ischemia and enhances contractile recovery in reperfusion. Emerging evidence suggests that the MR also contribute to sex-specific aspects of ischemic vulnerability. Indeed, MR interactions with sex steroid receptors may differentially regulate myocardial nitric oxide bioavailability in males and females, potentially determining sex-specific post-ischemic outcomes. There is hence considerable impetus for exploration of MR directed, cell specific therapies for both women and men in order to improve ischemic heart disease outcomes.

Care and Outcomes of ST-Segment Elevation Myocardial Infarction Across Multiple COVID-19 Waves

BACKGROUND

There are concerns of delays in ST-segment elevation myocardial infarction (STEMI) care during the COVID-19 pandemic. It is unclear whether the care and outcomes of STEMI patients differ between COVID-19 waves and compared with historical periods.

METHODS

Consecutive patients in the Vancouver Coastal Health Authority STEMI database were included to compare care during 3 distinct waves of the COVID-19 pandemic (9 months; March 2020 to January 2021) with an historical non-COVID-19 cohort. We compared STEMI incidence, baseline characteristics, and outcomes between groups. We also examined time from first medical contact (FMC) to reperfusion, symptom to FMC, and FMC to STEMI diagnosis, as well as predictors of delays.

RESULTS

The incidence of STEMI was similar during COVID-19 (n = 305; mean 0.93/day) and before COVID-19 (n = 949; 0.97/day; P = 0.80). The COVID-19 cohort showed significant delay in FMC-to-reperfusion (median 116 min vs 102 min; P < 0.001) and FMC-to-STEMI diagnosis (median 17 mins vs 11 min; P < 0.001). Delays in FMC-to-device times worsened across the 3 COVID-19 waves (FMC-to-device time ≤ 90 min in wave 1: 32.9%; in wave 2: 25.6%; in wave 3: 16.3%; P = 0.045 [47.5% before COVID-19; P < 0.001]). There were no significant predictors of delay were unique to the COVID-19 cohort.

CONCLUSIONS

This study demonstrates delays in reperfusion during the COVID-19 pandemic compared with the historical control, with delays increasing during subsequent waves within the pandemic. It is critical to further understand these care gaps to improve STEMI care for future waves of the current and future pandemics.