Extreme heat events (EHEs) are a leading cause of weather-related injury and death in the United States, and under a changing climate, these meteorological episodes are predicted to increase in both frequency and intensity. Prolonged heat exposure from EHEs places an increased strain on the heart and may lead to heat-related illness if the cardiovascular system fails to properly thermoregulate internal body temperature. Every individual is susceptible to heat-related illness, however, those with reduced cardiovascular function and pre-existing cardiovascular diseases are at a greater risk for morbidity and mortality during EHEs. This document gives an overview of our current understanding of heat exposure and its impact on cardiovascular health outcomes, an overview of the medications that may exacerbate heat-related cardiovascular illness, and asummary of the interaction between extreme heat and air pollutants, and their collective impact on cardiovascular health. Additionally, this document summarizes epidemiologic evidence and identifies gaps in the extant peer-reviewed literature on the effectiveness of strategies and interventions to protect against heat-related cardiovascular disease and death. This information is intended to aid health departments and other health professionals in understanding and responding to the impacts of heat exposure on cardiovascular health.