INfluenza Vaccine to Effectively Stop Cardio Thoracic Events and Decompensated Heart Failure

Inclusion Criteria: * \>= 18 years of age * history of hospitalization for myocardial infarction within 1 year of enrollment OR a history of hospitalization for heart failure within 2 years of enrollment * At least one of the following additional risk factors: * Prior MI (if HF the index event above; or a second MI) * Prior HF hospitalization (if MI the index event above; or a second HF event) * Age ≥ 65 * Left ventricular ejection fraction (LVEF) \< 40% * Diabetes mellitus * Obesity (BMI ≥ 30) * Renal impairment (eGFR ≤ 60) * History of ischemic stroke * History of peripheral artery disease * Current smoking Exclusion Criteria: * Known allergy, hypersensitivity (anaphylaxis), or Guillain-Barré Syndrome within 6 weeks after influenza vaccine * Any non-cardiac condition that in the opinion of the investigator would lead to life expectancy less than 9 months. * Receipt of influenza vaccine during current influenza season * Any illness requiring treatment with antibiotics or anti-inflammatory medication within the past 14 days. * Any fever over 100 degrees Fahrenheit or 38 degrees Celsius within the past 7 days.