The Impact of Concomitant Diagnosis of Viral Infections on in-Hospital Mortality in Patients Hospitalized with a Diagnosis of Heart Failure in the United States: Insights from the National Inpatient Sample

Cumulative incidence and mortality rate of cardiovascular complications due to laboratory-confirmed influenza virus infection: A systematic review and meta-analysis

Influenza infection is associated with cardiovascular complications that range significantly in presentation and severity. The cumulative incidence of cardiovascular complications due to laboratory-confirmed influenza, however, is not reported in the literature. We conducted a systematic review and random-effects meta-analysis to evaluate the cumulative incidence and mortality rate of influenza virus-related cardiovascular complications in hospitalized patients. We searched the PubMed and EMBASE databases for studies reporting acute myocardial infarction (AMI), heart failure (HF), arrhythmia of any kind, stroke or transient ischemic attack (TIA), and myocarditis in hospitalized patients with laboratory-confirmed influenza virus infection. Prospective studies, retrospective cohort studies, and randomized controlled trials (RCTs) were included in the analysis. We followed the PRISMA checklist and used 95% confidence intervals (CIs) to report meta-analysis outcomes. This study was registered on PROSPERO (CRD42023427849). After retrieving 2803 studies, we identified 19 studies (18 observational and 1 RCT) with relevant data, and we included 6936 patients in our analysis, of whom 690 (9.9%) developed a cardiovascular outcome of interest. The cumulative incidence of HF was 17.47% (95% CI: 5.06%-34.54%), arrhythmia of any kind 6.12% (95% CI: 0.00%-21.92%), myocarditis 2.56% (95% CI: 0.66%-5.38%), AMI 2.19% (95% CI: 1.03%-3.72%), and stroke or TIA 1.14% (95% CI: 0.00%-4.05%). The in-hospital mortality rate from cardiovascular events was 1.38% (95% CI: 0.00%-4.80%). Cardiovascular complications occur in patients with influenza virus infection, with the cumulative incidence of specific cardiac manifestations varying considerably (1.51%-17.47%). Preventive strategies and close clinical monitoring after infection remain a priority.

The Influence of Diagnoses of Specific Viral Infections on In-Hospital Mortality, Length of Stay and Cost in Patients Admitted to Hospital with a Diagnosis of Myocarditis: An Analysis of the National Inpatient Sample

Background

The influence of different viral infections in patients with myocarditis is unknown. Myocarditis is an inflammatory disease of heart muscle that is commonly caused by viruses. The impact of different viral infections in patients with myocarditis is unknown.

Methods

We conducted a retrospective cohort study using data between 2016-2020 in the National Inpatient Sample in the USA to evaluate admissions with myocarditis and concomitant viral infection. The outcomes of in-hospital mortality, length of stay (LoS), and cost, among patients hospitalized for myocarditis was evaluated.

Results

A total of 27,050 hospital admissions for myocarditis were included and 6750 (25.0%) had a co-diagnosis of viral infection. Patients with myocarditis and viral infection had significantly higher mortality compared to those without viral infection (23.6% vs. 4.4%, p < 0.001). Viral infection was associated with increased in-hospital mortality (odds ratio (OR) 2.03, 95% CI 1.51 to 2.73, p < 0.001), greater median LoS (7 vs. 3 days, p < 0.001) and median hospitalization cost ($21,445 vs. $11,596, p < 0.001), compared to patients without viral infection. The rate of death was greatest for patients with a diagnosis of coronavirus disease 2019 (COVID-19), viral pneumonia and herpes zoster, respiratory syncytial virus, chronic hepatitis, and influenza which was 36.0%, 34.3%, 27.3%, 21.4%, 20.0%, and 14.5%, respectively.

Conclusions

In conclusion, the diagnosis of viral infection is present in one in four patients hospitalized with myocarditis and is correlated with greater mortality, LoS, and in-hospital cost.