Medication, reperfusion therapy and survival in a community-based setting of hospitalised myocardial infarction

Racial Differences in Trends and Prognosis of Guideline-Directed Medical Therapy for Heart Failure with Reduced Ejection Fraction: the Atherosclerosis Risk in Communities (ARIC) Surveillance Study

BACKGROUND

Racial disparities in guideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF) have not been fully documented in a community setting.

METHODS

In the ARIC Surveillance Study (2005-2014), we examined racial differences in GDMT at discharge, its temporal trends, and the prognostic impact among individuals with hospitalized HFrEF, using weighted regression models to account for sampling design. Optimal GDMT was defined as beta blockers (BB), mineralocorticoid receptor antagonist (MRA) and ACE inhibitors (ACEI) or angiotensin II receptor blockers (ARB). Acceptable GDMT included either one of BB, MRA, ACEI/ARB or hydralazine plus nitrates (H-N).

RESULTS

Of 16,455 (unweighted n = 3,669) HFrEF cases, 47% were Black. Only ~ 10% were discharged with optimal GDMT with higher proportion in Black than White individuals (11.1% vs. 8.6%, p < 0.001). BB use was > 80% in both racial groups while Black individuals were more likely to receive ACEI/ARB (62.0% vs. 54.6%) and MRA (18.0% vs. 13.8%) than Whites, with a similar pattern for H-N (21.8% vs. 10.1%). There was a trend of decreasing use of optimal GDMT in both groups, with significant decline of ACEI/ARB use in Whites (- 2.8% p < 0.01) but increasing H-N use in both groups (+ 6.5% and + 9.2%, p < 0.01). Only ACEI/ARB and BB were associated with lower 1-year mortality.

CONCLUSIONS

Optimal GDMT was prescribed in only ~ 10% of HFrEF patients at discharge but was more so in Black than White individuals. ACEI/ARB use declined in Whites while H-N use increased in both races. GDMT utilization, particularly ACEI/ARB, should be improved in Black and Whites individuals with HFrEF.

Continuous Infusion of Angiotensin IV Protects against Acute Myocardial Infarction via the Inhibition of Inflammation and Autophagy

Acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide. Angiotensin (Ang) IV possesses many biological properties that are not yet completely understood. Therefore, we investigated the function and mechanism of Ang IV in AMI in in vivo and in vitro conditions. AMI was performed by ligation of the left anterior descending coronary artery (LAD) in male C57 mice. Ang IV was continuously infused by a minipump 3 d before AMI for 33 d. The neonatal rat ventricular myocytes (NRVCs) were stimulated with Ang IV and cultured under hypoxic conditions. In vivo, Ang IV infusion significantly reduced the mortality after AMI. By the 7^th day after AMI, compared with the AMI group, Ang IV reduced the inflammatory cytokine expression. Moreover, terminal deoxyribonucleotidyl transferase- (TDT-) mediated dUTP nick-end labeling (TUNEL) assay showed that Ang IV infusion reduced AMI-induced cardiomyocyte apoptosis. Compared with AMI, Ang IV reduced autophagosomes in cardiomyocytes and improved mitochondrial swelling and disarrangement, as assessed by transmission electron microscopy. By 30^th day after AMI, Ang IV significantly reduced the ratio of heart weight to body weight. Echocardiography showed that Ang IV improved impaired cardiac function. Hematoxylin and eosin (H&E) and Masson staining showed that Ang IV infusion reduced the infarction size and myocardial fibrosis. In vitro, dihydroethidium (DHE) staining and comet assay showed that, compared with the hypoxia group, Ang IV reduced oxidative stress and DNA damage. Enzyme-linked immunosorbent assay (ELISA) showed that Ang IV reduced hypoxia-induced secretion of the tumor necrosis factor- (TNF-) ɑ and interleukin- (IL-) 1β. In addition, compared with the hypoxia group, Ang IV reduced the transformation of light chain 3- (LC3-) I to LC3-II but increased p62 expression and decreased cardiomyocyte apoptosis. Overall, the present study showed that Ang IV reduced the inflammatory response, autophagy, and fibrosis after AMI, leading to reduced infarction size and improved cardiac function. Therefore, administration of Ang IV may be a feasible strategy for the treatment of AMI.

Factors related to the use of reperfusion strategies in elderly patients with acute myocardial infarction

Background

About eighty percent of acute myocardial infarction (AMI) cases occur in the elderly, we aim to examine the use of reperfusion strategies in elderly patients (≥65 years) with AMI and to investigate the factors affecting the use of these strategies.

Methods

A total of 352 consecutive elderly patients (≥65 years) with ST-elevated AMI (STAMI) were admitted, they were divided into 2 groups based on reperfusion treatment (thrombolysis or percutaneous coronary intervention, PCI): reperfusion therapy group (n = 268) and non-reperfusion therapy group (n = 84). Demographic and medical data were collected for comparison. Odds ratios (OR) and 95% confidence interval (C.I.) were calculated directly from the estimated regression coefficients.

Results

About 76.1% of the elderly patients with AMI received reperfusion treatment (62.5% received PCI, and 13.6% received thrombolysis). Stepwise Logistic regression analysis revealed that a patient age ≥75 years (95% CI: 0.194 ~ 0.590, OR = 0.338, P = 0.000) and medical history of angina (95% CI: 0.281 ~ 0.928, OR = 0.501, P = 0.014) were determining factors for receiving less reperfusion therapy. Complications including right ventricular myocardial infarction (MI) (95% CI: 1.618 ~ 12.907, OR = 4.472, P = 0.003), unbearable symptoms (95% CI: 1.132 ~ 3.928, OR = 1.839, P = 0.021) and medical insurance (95% CI: 1.313 ~ 4.524, OR = 2.429, P = 0.004) were independent predictors of reperfusion therapy. The reperfusion therapy subset analysis revealed that intracranial hemorrhage (2.7% vs. 8.3%, P = 0.000), left ventricular ejection fraction (LVEF) <45% (13.2% vs. 29.2%, P = 0.019) and mortality rate within 1 year (2.7% vs. 6.3%, P = 0.045) were significantly decreased in the PCI group as compared with thrombolysis.

Conclusion

Elderly patients with a medical history of angina, right ventricular MI, unbearable symptoms and medical insurance are likely be recipients of reperfusion strategies.