Maybe it put too much pressure on a damaged heart
Hot tubs can increase heart rate due to the high water temperature which can raise body temperature, dilate blood vessels, and cause dehydration. The body responds to the higher temperature by working harder to maintain blood flow, which increases the heart rate and metabolic rate. This can be concerning for individuals with pre-existing heart conditions and may require clearance from a doctor before use. It is recommended to limit time in a hot tub to no more than 15-20 minutes to avoid overheating or dehydration.