Decreased cardiovascular capacity and heart disease can occur because of damage to the heart muscle from chemotherapy treatments. Radiotherapy to the chest can also cause damage to the heart. These side effects (cardiotoxicity) are more prevalent in children and older people, in those with a pre-existing heart condition, and in those treated with a combination therapy. Common heart conditions that may develop are:
- Congestive heart failure, which is a weakening of the heart muscle, which may cause shortness of breath, dizziness, and swollen hands or feet.
- Heart disease of the coronary arteries tends to happen more often with radiation to the chest; symptoms are shortness of breath and chest pain.
- Irregular heart beat or arrhythmia, which might produce light-headedness, chest pain, and shortness of breath.
- High blood pressure or hypertension might occur on its own, or together with congestive heart failure.