Dr. Paaladinesh Thavendiranathan and his colleagues at Toronto General Hospital Research Institute and Mount Sinai Hospital have found that pregnant women who have previously received treatment for cancer are at an increased risk for heart disease.
During pregnancy, the heart needs to work harder to satisfy the increased day-to-day demands of the body. Women with reduced heart function are at an increased risk of heart failure during pregnancy. Cancer can also increase the risk of heart disease.
"Many drugs used for chemotherapy cause damage to the heart, which may lead to conditions such as coronary heart disease and congestive heart failure," explains Dr. Thavendiranathan.
"Some radiation therapy can also be tough on the heart. Many cancer survivors recover from such heart damage with time, others don't and may not even be aware of it."
The research team found that women who did not experience heart damage from cancer treatment are at a very low risk of developing heart failure during pregnancy; women who did have heart damage from cancer treatment have approximately one-in-three chance of developing heart failure during pregnancy.
This study addresses gaps in previous works by specifically and methodically following cancer survivors through pre- and post-pregnancy assessments in a dedicated high risk pregnancy program at Mount Sinai Hospital lead by Dr. Cynthia Maxwell. It also provides information to help doctors provide pre-conception counselling.
"Women with a history of heart problems related to cancer treatment – even if they have recovered – should have a cardiologist as part of their care if they are pregnant," says Dr. Thavendiranathan. "They should receive close monitoring during pregnancy at a centre with expertise in cardiac disease in pregnancy."
One such centre is the Peter Munk Cardiac Centre at UHN, which has an established program in Pregnancy and Heart Disease lead by Dr. Candice Silversides.
"If you have a history of heart damage and are thinking about pregnancy, talk to your doctor about your risk of heart disease during pre-conception counselling," urges Dr. Thavendiranathan. "The heart is unlikely to fail if abnormalities are discovered early and managed properly."
This work was supported by the Canadian Institutes of Health Research and the Toronto General & Western Hospital Foundation.
