Only a few studies describe the pathophysiology and outcomes of dilated cardiomyopathy (DCM) in pregnancy, which the authors aim to review here. DCM causes enlargement of the ventricles and reduced systolic function. Fluid overload and raised cardiac output in pregnancy may contribute to cardiac complications that lead to cardiac remodeling and heart failure, a common cause of maternal mortality. The risk of cardiac complications is higher in women with New York Heart Association class III and IV. Fetal and neonatal complications are common with coexisting obstetric risk factors. Hence, prepregnancy counseling and a multi-disciplinary approach are essential. Renin-angiotensin-aldosterone system blockers prevent cardiac remodeling but are teratogenic. Drugs, such as β-blockers to control cardiac remodeling, thiazide diuretics to reduce preload, hydralazine and nitrates to reduce afterload and digoxin to increase inotropy, are safe and should be used to manage DCM in pregnancy.
Keywords: B-type natriuretic peptide; arrhythmia; dilated cardiomyopathy; echocardiography; heart failure; pregnancy; premature birth; renin–angiotensin–aldosterone system; small for gestational age; β-blockers.
Dilated cardiomyopathy (DCM) is a rare disease of the heart associated with the enlargement of its chambers and subsequent reduction in its pumping ability. The authors aim to describe the disease process, presentation and treatment of DCM in pregnancy in this review article. A physiological change in pregnancy is an increase in the total blood volume to ensure blood supply to the fetus. This can, however, have a negative impact on the already diseased heart in DCM and present as heart failure in pregnancy. The clinical outcomes of DCM in pregnancy depend on heart health prior to pregnancy. During pregnancy, the mother can suffer from cardiac events, such as heart failure, arrhythmias and sudden death, whereas the fetus may be born prematurely and be small for gestational age. Drugs useful in slowing the progression of DCM, such as angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, are contraindicated in pregnancy. Hence, such women require careful monitoring throughout pregnancy by a multi-disciplinary team. Drugs that can be safely used to manage DCM include β-blockers, thiazide diuretics and digoxin. More comprehensive studies on DCM in pregnancy are needed to better understand the disease process and accordingly counsel and treat women with this condition in pregnancy.