Impact of Arrhythmia in Hospital Mortality in Acute Ischemic Stroke Patients: A Retrospective Cohort Study in Northern Mexico

Cardiac arrhythmia following acute myocardial infarction: a retrospective analysis of 27,648 hospitalized patients in a tertiary heart hospital

Arrhythmia frequently complicates acute myocardial infarction (AMI) and contributes to high morbidity and mortality. We aimed to investigate the prevalence, risk factors, and impact of cardiac arrhythmias in AMI patients at a tertiary heart hospital. This retrospective observational study included AMI patients who were admitted between January 1991 and May 2022. Patients' data were analyzed and compared according to the absence or presence of cardiac arrhythmias post-AMI. We hypothesized that arrhythmias are associated with higher mortality following AMI. During the study, 27,648 patients were hospitalized with AMI, of whom 2118 (7.7%) developed arrhythmia. Patients who developed arrhythmia had a higher average age compared to those without arrhythmia (57.2 vs. 54.8 years, p=0.001), and a larger proportion were male compared to female patients (85.2% vs. 14.8%, p=0.001). Atrial fibrillation was observed in 383 patients (18.1%). Ventricular tachycardia was found in 461 (21.8%), and ventricular fibrillation occurred in 526 patients (24.8%). Complete heart block was developed in 286 (13.5%) patients, 1st-degree atrioventricular (AV) block in 36 (1.7%), 2nd-degree AV block in 138 (6.5%), left bundle branch block in 81 (3.8%), and right bundle branch block in 118 (5.6%). The rate of β-blocker use has increased in the arrhythmias group at discharge compared to the on-admission rate (55.7% vs. 32.5%). However, it remained sub-optimal. Arrhythmias were associated with longer hospital stays and five times higher hospital mortality than the non-arrhythmia group. Multivariable logistic regression analysis indicated that arrhythmia was associated with increased mortality risk three times following AMI (adjusted odds ratio 3.01; 95% confidence interval 2.42-3.75, p=0.001). Almost one-tenth of patients hospitalized with AMI in Qatar developed arrhythmia with variable outcomes; however, the in-hospital mortality remained high. Addressing the risk factors and optimizing the prevention and treatment of AMI and arrhythmias is crucial to improving clinical outcomes. This study may underestimate the incidence of arrhythmias post-AMI as it did not report all types.

Atrial Cardiomyopathy Predicts the Functional Outcome and Mortality in Stroke Patients

AIM

Atrial cardiomyopathy (ACM) is characterized by atrial dysfunction. This study aims to assess the prognostic significance of ACM in patients with noncardioembolic stroke (NCS).

METHODS

Patients with NCS within seven days of onset were prospectively enrolled between January 2019 and December 2020. ACM was defined as either an N-terminal pro-brain natriuretic peptide (NT-pro BNP) ＞250 pg/ml or a P-terminal force in precordial lead V1 (PTFV1) ≥ 5000µV·ms. A poor functional outcome was determined as a score of 3-6 on the modified Rankin Scale (mRS) within a 2-year follow-up period. Logistic regression and Cox regression analyses were employed to examine the relationship between ACM and the long-term prognosis of patients with NCS.

RESULTS

A total of 1,346 patients were enrolled, of whom 299 (22.2%) patients were diagnosed with ACM. A total of 207(15.4%) patients experienced a poor functional outcome, and 58 (4.3%) patients died. A multivariate logistic regression analysis indicated that ACM was significantly associated with a poor functional outcome in NCS patients [adjusted odds ratio (aOR): 2.01; 95% confidence interval (CI): 1.42-2.87; p＜0.001]. Additionally, a multivariate Cox regression analysis showed that an NT-pro BNP ＞250 pg/ml was significantly associated with an increased risk of all-cause mortality [adjusted hazard ratio (aHR), 2.51; 95% CI: 1.42-4.43; p=0.001].

CONCLUSIONS

ACM may serve as a novel predictor of a poor long-term functional outcome in patients with NCS. Elevated NT-pro BNP levels (＞250 pg/ml) were found to be associated with a higher risk of all-cause mortality. These findings warrant further validation in multicenter studies.

Liraglutide inhibits AngII-induced cardiac fibroblast proliferation and ECM deposition through regulating miR-21/PTEN/PI3K pathway

BACKGROUND

Cardiac fibrosis characterized with the aberrant proliferation of cardiac fibroblasts and extracellular matrix (ECM) deposition is a major pathophysiological feature of atrial fibrillation (AF). Liraglutide has exerted an alleviative role in various cardiovascular diseases, and can also regulate the level of microRNAs (miRNAs). It has been reported that miR-21 modulated cardiac fibrosis in AF. However, the regulative effect of liraglutide on atrial fibrosis via miR-21 and the underlying mechanism are still unclear.

METHODS

The atrial fibroblasts were isolated from the heart of C57BL/6 mice, and treated with Angiotensin II (AngII) and liraglutide. The proliferation, migration, and ECM deposition were determined by cell counting Kit-8 (CCK-8), Brdu, transwell assay, cell scratch, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), western blot and immunofluorescence. The underlying mechanism was explored after transfection of miR-21 mimics into cells.

RESULTS

Liraglutide inhibited proliferation, migration, invasion of fibroblast cell and ECM deposition in AngII-stimulated cardiac fibroblasts. Additionally, liraglutide decreased the AngII-induced increase in the expression level of miR-21, but enhanced the expression of phosphatase and tensin homolog (PTEN), a target of miR-21, thereby suppressing the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway. Rescue assay confirmed that overexpression of miR-21 counteracted the ameliorative effect of liraglutide on the proliferation, migration, invasion and ECM deposition in fibroblasts stimulated by AngII.

CONCLUSIONS

Liraglutide dampened AngII-induced proliferation and migration, and ECM deposition of cardiac fibroblast via modulating miR-21/PTEN/PI3K pathway.