Patients with HFrEF taking carvedilol had improved survival as compared to metoprolol succinate. The data supports the need for furthering testing to determine optimal choice of beta blockers in patients with heart failure with reduced ejection fraction.
This study aimed to compare the effect of β-blocker dose and heart rate (HR) on mortality in patients with heart failure with reduced ejection fraction (HFrEF). The Veteran Affairs databases were queried to identify all patients diagnosed with HFrEF based on International Classification of Diseases Ninth Revision codes from 2007 to 2015 and β-blocker (carvedilol or metoprolol succinate) use. 36,168 patients on low dose β blocker were then matched with 36,168 patients on high dose β-blocker using propensity score matching. The impact of β-blocker dose and HR was assessed on overall mortality using Cox proportional hazard model. After dividing average HR into separate quartiles and adjusting for patient characteristics, high β-blocker dose was associated with lower overall mortality as compared with a low dose of β blocker (hazard ratio 0.75, 95% confidence interval 0.73 to 0.77, p <0.01) independent of the HR achieved. The results held for all 4 quartiles of average HR. A higher β-blocker dose or a lower HR were independently and jointly associated with lower mortality for all quartiles of HR. In conclusion, higher dose of β-blocker therapy and a lower achieved HR were independently associated with a reduction in mortality in HFrEF patients.
Background/Objective:
Respiratory syncytial virus (RSV) causes acute respiratory infections in children and adults. RSV has many non-specific symptoms such as cough and dyspnea. RSV is associated with high mortality in children, the elderly, and immunocompromised individuals. Although rare, RSV has been reported to cause extrapulmonary complications such as arrhythmias and myocarditis. This case focuses on a patient infected with RSV who presents with acute sustained monomorphic ventricular tachycardia (SMVT).
Case Overview:
An 83 year-old patient with a history of type 2 diabetes mellitus, hypertension, persistent atrial fibrillation, and asthma presented to the emergency department with concerns of cough, malaise, and a syncopal episode. Upon admission, the patient tested positive for RSV and was diagnosed with acute bronchitis exacerbated by history of asthma. The patient soon developed SMVT with heart rates as high as 235 beats per minute. After consultation with an electrophysiologist, the VT was attributed to myocarditis as a result of the RSV infection. Oral amiodarone was prescribed, and the patient was discharged two weeks later. In a follow-up visit, no SMVT was reported, and the dosage of amiodarone was decreased.
Discussion:
With the onset of the SARS-CoV2 pandemic in early 2020, myocarditis associated with viral infection has been of interest in recent literature. Many cases of cardiovascular complications have been reported in patients infected with SARS-CoV2. Consequently, it is important to discuss cases of other respiratory viruses also presenting with arrhythmia and myocarditis. In the current case, a patient with RSV developed new onset VT. VT can be life-threatening and can cause further cardiovascular complications.
Conclusion:
RSV can cause new onset cardiovascular complications, albeit rare. It is important for clinicians to be aware of such complications especially in cases in which patients have preexisting cardiovascular conditions. Patients infected with RSV should be closely monitored for new onset complications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.