Prognostic value of early sustained ventricular arrhythmias in ST-elevation myocardial infarction treated by primary percutaneous coronary intervention: a sub-study of VALIDATE-SWEDEHEART trial

Ventricular Tachycardia and Hospital Readmission in Patients Discharged From the Hospital After an Acute Myocardial Infarction

Background

Although ventricular tachycardia (VT) occurring during hospitalization for an acute myocardial infarction (AMI) increases mortality risk, its relationship with 30-day postdischarge rehospitalization has not been examined.

Methods

Using data from the Worcester Heart Attack Study, we examined the association between early (during the first 48 hours of admission) and late (after 48 hours from admission) VT with 30-day postdischarge all-cause and cardiovascular disease (CVD)-related rehospitalization while analytically controlling for several demographic and clinical factors.

Results

The study population consisted of 3534 patients who were hospitalized with an AMI between 2005 and 2015 (average age, 67.2 years; 40.7% women); VT occurred in 452 patients (13.7%), with the majority of instances (81.2%) occurring within 48 hours of admission. The 30-day all-cause rehospitalization rate was 17.3%, with 70.9% of the hospitalizations related to CVD. The odds of rehospitalization were 1.63 times (95% confidence interval [CI] = 0.99-2.69) and 1.12 times (95% CI = 0.83-1.51) higher for patients with AMI who developed late VT and early VT, respectively, compared to patients who did not develop VT. The risk of rehospitalization among patients with late VT was higher (odds ratio = 2.22 (95% CI = 0.79-6.26) in those with ST-segment-elevation AMI, compared to those with non-ST-segment-elevation AMI (odds ratio = 1.45 (95% CI = 0.81-2.57); early VT was not associated with rehospitalization in patients with either AMI subtype. No significant association was present between the occurrence of VT and CVD-related rehospitalization.

Conclusions

Patients who develop late VT may experience a higher risk of 30-day rehospitalization following hospital discharge for AMI, especially among those with ST-segment-elevation AMI. Larger studies are needed to confirm our findings.

Icariin improves cardiac function and remodeling via the TGF-β1/Smad signaling pathway in rats following myocardial infarction

BACKGROUND

Postinfarction cardiac remodeling presents a compensatory mechanism aimed at mitigating congestive heart failure. It is distinguished by progressive dilatation and hypertrophy of the ventricular chambers, fibrotic alterations, and prolonged apoptosis of cardiomyocytes. The primary objective of this study was to assess the effects of icariin on myocardial fibrosis and ventricular remodeling in rats subjected to myocardial infarction (MI).

METHODS

Male Sprague‒Dawley (SD) rats were subjected to randomization and subsequently divided into distinct groups: the control group, the sham group (undergoing sham operation), the MI group (experiencing ligation of the left anterior descending artery), and the icariin group. Within the icariin group, rats were further categorized into three different dose groups based on the administered icariin dosage: the MI30 group (30 mg/kg/day), the MI60 group (60 mg/kg/day), and the MI120 group (120 mg/kg/day). Cardiac function evaluation was carried out using echocardiography. Histological examinations, including hematoxylin and eosin (HE) staining, Masson staining, and immunohistochemistry studies, were conducted 90 days after the occurrence of MI. Additionally, Western blotting was employed to assess TGF-β1, p-Smad2, and p-Smad3 levels.

RESULTS

The administration of icariin revealed a noteworthy enhancement in cardiac function among rats afflicted with left anterior descending coronary artery (LAD) ligation. In comparison to the icariin groups, the MI group exhibited reduced EF and FS, along with elevated LVEDD and LVESD. Furthermore, the cardiac fibrosis levels in the MI group rats exhibited a considerable increase compared to those in the icariin group. Notably, the levels of Collagen I, Collagen III, MMP2, and MMP9 were significantly higher in the MI group than in the icariin group, with evident distinctions. Moreover, the expression levels of TGF-β, IL-13, p-Smad2, and p-Smad3 were notably upregulated in the MI group compared to the icariin group.

CONCLUSIONS

In an experimental rat model of MI, the administration of icariin resulted in the amelioration of both cardiac function and remodeling processes, operating through the intricate TGF-β1/Smad signaling pathway.