Introduction
Heart failure (HF) is a clinical syndrome caused by malfunction of the heart’s ability to pump blood to the rest of the body due to impaired ventricular filling or ejection. Clinical manifestations encompass a large constellation of signs and symptoms of volume overload. HF affects over 6 million Americans(1) and costing the healthcare system up to 32 billion dollars annually(2). When unmanaged, it can be debilitating, rapidly progressive and ultimately fatal.
Throughout decades of research, the scientific community has identified various etiologies of HF that range from common conditions such as coronary artery disease and valvular diseases, to less common conditions such as infections(3, 4). Several studies have repeatedly shown that influenza infection represent a significant hazard for patients with heart failure. Sepsis was shown to increase hospitalization of heart failure and mortality. More recently amidst the COVID-19 pandemic, there have been reports of increased incidence of heart failure in patients with acute COVID-19 infection(5).
Based on the role of infections on heart failure, it was reasonable to hypothesize that vaccines may curb the deleterious effects of infections on heart failure. Indeed, several studies have demonstrated a cardioprotective of annual influenza vaccine(6, 7). Influenza vaccination reduced all-cause mortality in patients enrolled on PARADIGM-HF(8). Additionally, pneumococcal vaccination was associated with lower heart failure incidence and all-cause mortality(9). Based on these studies, the 2022 American College of Cardiology/American Heart Association/ Heart Failure Society of America HF guidelines encouraged vaccination for heart failure patients(10).
Whereas the previous strongly showed a positive impact of vaccination on heart failure, a comprehensive evaluation of the role of vaccination in heart failure is lacking especially with the evolving techniques and types of vaccines, such as mRNA vaccines. For example, previous case reports described an association between Takotsubo (stress) cardiomyopathy and COVID-19 vaccine(11). Therefore, we decided to analyze VAERS database to provide the first comprehensive evaluation of the association between vaccines and cardiomyopathy/heart failure.