Heatwaves may seem like a mild inconvenience, but they pose a real threat to cardiovascular health—especially for those with pre-existing heart conditions. As the UK endures another spell of high temperatures, cardiologists caution that the heart faces extraordinary stress trying to keep the body cool.
Dr Francesco Lo Monaco, founder of The National Heart Clinic, explains that during extreme heat, the heart’s workload can increase dramatically. “Under normal conditions, the heart pumps about five litres of blood per minute. In heatwaves, blood vessels dilate and heart rate rises to push more blood to the skin surface, facilitating heat loss,” he says. “At the same time, sweating leads to the loss of water and vital electrolytes, making it harder to maintain steady blood pressure and circulation.”
Scientific research has linked heatwaves with spikes in cardiovascular complications and fatalities, primarily affecting vulnerable groups. Dr Lo Monaco identifies people with coronary artery disease, heart failure, previous heart attacks or strokes, and high blood pressure as especially at risk during hot weather. Additionally, those with diabetes, kidney disease, obesity, or older adults who struggle with temperature regulation and hydration also face heightened danger.
READ MORE: Seven Million-Pound Homes Currently for Sale in the Cotswolds
READ MORE: Winning EuroMillions Numbers and Thunderball Results – Friday, June 26, 2026
While feeling warm or fatigued during heat is common, some symptoms should never be ignored or attributed simply to the heat. Dr Lo Monaco warns: “Chest pain, severe breathlessness, palpitations, confusion, or fainting require immediate medical evaluation—they are red flags, not just ‘heat-related’ discomfort.”
The good news is many heat-related heart risks can be prevented. Staying well hydrated, avoiding intense physical activity during the hottest times of the day, seeking shade or air-conditioned environments, wearing lightweight clothing, and limiting alcohol consumption can all ease the strain on the cardiovascular system.
“Heatwaves increase demands on the heart, but simple steps can reduce these risks,” Dr Lo Monaco advises. “Maintaining hydration, sensible activity, balanced nutrition, and overall heart health becomes even more critical during extreme heat periods. Prevention is a powerful tool to safeguard long-term cardiovascular wellbeing.”