From the Guidelines
Influenza infection is associated with an increased risk of cardiomyopathy, particularly in individuals with pre-existing heart conditions. The evidence suggests that influenza vaccination can reduce the risk of cardiovascular events, including cardiomyopathy, in individuals with known coronary and other atherosclerotic conditions 1.
Key Points
- Influenza virus can cause inflammation of the heart muscle (myocarditis) which may lead to cardiomyopathy, a disease that affects the heart's ability to pump blood effectively.
- The virus can directly invade heart tissue or trigger an abnormal immune response that damages the heart.
- Patients with influenza who develop chest pain, shortness of breath, palpitations, or unusual fatigue should seek medical attention promptly as these may indicate cardiac involvement.
- Treatment typically involves supportive care, management of heart failure symptoms if present, and antiviral medications like oseltamivir (Tamiflu) if the infection is caught early.
- Annual influenza vaccination is recommended to reduce the risk of influenza and its cardiac complications, especially for individuals with pre-existing heart conditions who are at higher risk for developing cardiomyopathy following influenza infection.
Recommendation
Annual influenza vaccination is strongly recommended for individuals with pre-existing heart conditions to reduce the risk of cardiomyopathy and other cardiac complications 1. This recommendation is based on the evidence from cohort studies and a randomized clinical trial that indicates annual vaccination against seasonal influenza prevents cardiovascular morbidity and all-cause mortality in patients with cardiovascular conditions 1.
Important Considerations
- Influenza vaccination coverage levels among persons with cardiovascular disease remain well below national goals and are marked by disparities across age categories and ethnic groups 1.
- Healthcare providers who treat individuals with cardiovascular disease can help improve influenza vaccination coverage rates by providing and strongly recommending vaccination to their patients before and throughout the influenza season 1.
From the Research
Influenza Infection and Cardiomyopathy
- Influenza infection has been associated with various cardiovascular complications, including direct myocardial involvement presenting as myocarditis, which can lead to cardiogenic shock and death 2.
- The infection can also exacerbate existing cardiovascular disease, leading to increased rates of myocardial infarction and cardiovascular mortality 2, 3.
- Studies have shown that influenza vaccination can reduce the risk of cardiovascular events and mortality in patients with cardiovascular disease 4, 5.
Cardiovascular Complications of Influenza Infection
- Myocarditis is a known complication of influenza infection, and can range from asymptomatic to fulminant, resulting in cardiogenic shock and death 2.
- Influenza infection can also lead to increased rates of myocardial infarction, particularly in patients with pre-existing coronary artery disease 2, 3.
- Cardiovascular mortality is increased during influenza epidemics, especially in patients with pre-existing cardiovascular disease 2, 3.
Role of Influenza Vaccination in Preventing Cardiovascular Complications
- Influenza vaccination has been shown to reduce the risk of cardiovascular events and mortality in patients with cardiovascular disease 4, 5.
- The vaccine has been associated with a lower risk of major adverse cardiovascular events, including myocardial infarction and stroke 5.
- Influenza vaccination is recommended for adults with cardiovascular disease, particularly those with high-risk conditions such as coronary artery disease 6.