If you enjoy relaxing in a hot tub but have a heart condition, soak with caution. Medical experts say sudden or extended immersion in hot water can superheat your body and stress your heart.
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“Hot tubs and saunas are potentially dangerous for patients with known or suspected heart disease,” says cardiologist Curtis Rimmerman, MD.
However, awareness and common sense can help keep you safe while you soak, he says.
Common-sense hot tub tips
Talk with your doctor before enjoying a soak. If you get the go-ahead, follow these tips to keep yourself safe:
- Regulate water temperature. Most hot tubs have a temperature control and thermometer.
- Limit your exposure to hot water. Most experts say no more than five to 10 minutes is safe.
- Stay hydrated. Keep a bottle of cool water nearby and sip as you soak.
Cooling process and your heart
When you submerge your body in hot water, your temperature rises, but your blood pressure drops.
Evaporating sweat normally helps cool you off. But, when you immerse yourself in hot water, that natural cooling mechanism doesn’t work. As a result, you can’t cool off.
When your body gets superheated:
- Your blood vessels dilate to try to help cool off the body.
- Blood diverts to the skin, away from the body core.
- Heart rate and pulse increase to counteract a drop in blood pressure.
Normally, these events don’t cause problems. However, if you have existing cardiovascular disease, the cascade of events could overtax your heart. This can lead to:
- Loss of adequate blood pressure, if your heart can’t pump enough blood
- Increased blood pressure, if you have blood vessel disease or narrowing and hardening of the arteries
- Dizziness or feelings of faintness
- Abnormal heart rhythms
- Inadequate blood flow to the heart or body
- Heart attack
Medications prescribed for heart conditions can also contribute to the problem:
- Beta-blockers lower heart rate and limit cutaneous (skin) blood flow.
- Diuretics increase excretion of water and salt.
A cardiologist’s advice
Dr. Rimmerman describes the process this way: “A sudden rise in body temperature creates significant stress on the cardiovascular system, predominantly via a cascade of adjustments resulting in an elevated heart rate. The higher heart rate — especially in the presence of reduced heart function, heart arrhythmias and coronary artery blockages — can precipitate a cardiac event such as blood flow problems and, in the worst case scenario, manifest as a heart attack.”
Go ahead and relax — safely
Dr. Rimmerman advises patients to keep safety in mind even when relaxing in a Jacuzzi. “My best advice is to make sure the water temperature is not too high, to stay hydrated, and if you choose to use a hot tub or sauna — especially if you are a heart patient — engage in the activity for only brief periods of time.”