How Cancer Treatment Can Affect the Heart
When a pet is being checked or treated for cancer, it’s important to understand that the heart can be affected in several ways. Dr Samantha, Specialist in Veterinary Cardiology mentioned that the stress of illness—along with the stress of hospital visits, procedures, or anaesthesia—can sometimes reveal heart problems that weren’t apparent before. Some pets with heart disease show no outward signs until they undergo cancer related procedures.
When a pet is being checked for cancer, they often need sedation or general anaesthesia. While modern anaesthesia is very safe, especially when performed under ideal conditions, it can place extra stress on the heart. Most anaesthetic drugs naturally reduce heart strength and may lower blood pressure or trigger irregular heartbeats. For pets with existing heart disease, these effects can be more serious. Understanding a pet’s cardiac health before the procedure helps the veterinary team choose the safest anaesthesia plan and, if needed, start medications beforehand.
Cancer treatments can also influence the heart. A commonly used chemotherapy drug, doxorubicin, is very effective but known to be potentially harmful to the heart—especially in pets with some pre-existing heart muscle issues. Over time, repeated doses can make the heart weaker or cause rhythm problems. If a pet has heart disease, the oncology team may choose to adjust the treatment plan to reduce the risk.