Some drugs used in chemotherapy to treat cancer are known to cause damage to the heart muscle. The most common of these are anthracyclines (e.g. doxorubicin), antibiotic anticancer drugs, and allothiolate compounds. These drugs can directly damage the myocardium (myocardial cells) and cause an inflammatory response that leads to fibrosis (hardening of the tissue) and an inability of the heart to pump blood effectively.
Chemotherapy drugs can cause chemotherapy-induced cardiomyopathy or chemotherapy-induced cardiotoxicity and cause damage that leads to heart failure.
The development of cardiotoxicity depends on several factors, including:
- The dose and duration of chemotherapy: Higher doses and longer duration of treatment increase the risk.
- The age of the patient, especially very young or very elderly patients.
- People with pre-existing heart problems (e.g., hypertension or coronary artery disease) are more vulnerable to the effects of chemotherapy.
Symptoms
Chemotherapy-induced cardiomyopathy can cause:
- Shortness of breath and fatigue even during daily activities.
- Swollen feet, abdomen or ankles due to fluid retention.
- Palpitations or other arrhythmias.
- Chest pain in severe cases.
Cancer patients with the above symptoms should see a cardiologist who specializes in cardiomyopathy.
The prognosis for chemotherapy-induced cardiomyopathy depends on the degree of heart damage caused by the chemotherapy drugs and the treatment received. If cardiomyopathy is recognized early and treated properly, patients may recover completely or manage the disease with medication. In more severe cases, treatment may include implanting a defibrillator to control dangerous arrhythmias.
Diagnosis at the Clinic includes an echocardiogram to assess cardiac function and cardiac endurance. Also, evaluation of markers of cardiac damage. A cardiac MRI may be requested for more accurate imaging of the heart.
