Peripartum cardiomyopathy

PC complicates approximately one in 2000 births worldwide: wide variation as 1 in 300 births in Haiti, and 1 in 100 in parts  of Nigeria.

In the US PC is four times as likely to develop in Black women as it is in White women.

Black women are more likely than White women to present later in the postpartum period.

Black women have worse outcomes than White women.

The incidence of PC is increasing due to the increasing age of mothers, and increased recognition of this process.

20% of women with this disorder die or survive because of cardiac transplants and the majority recover partially or completely.

Subsequent pregnancy in women with a history of peripartum cardiomyopathy is associated with a significant decrease in left ventricular function, clinical deterioration and even death.

PC is now a leading cause of maternal death in many parts of the US and around the world.

Risk factors for its development include older maternal age, African-American ethnicity, multiparity, antecedent hypertension and preeclampsia.

Accounts for approximately 60% of cases of cardiogenic shock during pregnancy.

It is a potentially lethal sequela of normal pregnancy and should be considered in any patient presenting with heart failure symptoms in the third trimester of pregnancy up to the first few months in the postpartum period.

About 50% of patients with PC fully recover, but morbidity and mortality are high and some patients require a left ventricular assist device or cardiac transplantation.

Black women in the US are twice as likely as White women to have persistent heart function impairment, and in those that do recover, it takes twice as long to do so.

Mortality rates are as high as 20%, and higher in Black women in the US and in the less developed world.

Diagnosis consists of: signs/symptoms of heart failure developing one month antepartum to five months postpartum, no evidence of pre-existing heart disease, ejection fraction reduced to less than 45%, and the absence of another recognizable cause for heart failure.

PC is a diagnosis of exclusion with differential diagnosis including: pre-existing structural heart disease, preeclampsia, induced pulmonary edema, pulmonary embolism, coronary artery, dissection, exposure to toxins, including alcohol and chemotherapy.

Cardiac MRI can be helpful in evaluating systolic function in cardiac structure.

BNP levels are usually elevated with PC.

The diagnosis is generally made by echocardiography, with documentation of systolic dysfunction in the absence of other structural heart disease.

Patients typically present with symptoms and signs of heart failure that include: dyspnea, orthopnea, elevated  jugular, venous pressure, pulmonary rales , and edema.

Elevated anti-proBNP may be helpful in diagnosis.

The proposed mechanism is the role of prolactin: its breakdown products may damage cardiac vasculature.

Intrinsic cardiac factors render some women susceptible to hormonal imbalances from pituitary and placental hormones that normally modulate maternal physiology to support fetal and newborn growth and development.

In genetically susceptible patients, activation of enzymes that cleave prolactin lead to pro inflammatory proteins that lead to cardiomyocyte apoptosis.

Bromocriptine management is reserved for patients who are extremely ill, as it suppresses lactation and is associated with thrombotic  complications.

Therapy during the postpartum. Includes diuretics, enalapril and beta blockers, which are safe during breast-feeding and are first line treatments.

Most patients recover left ventricular function within six months after diagnosis if their initial LVEF is greater than 30%.

High rate of recurrence of peripartum cardiomyopathy occurs in subsequent pregnancies.

management of labor and delivery in patients with peripartum cardiomyopathy can be complex.

Patients who are hemodynamically stable, can deliver vaginally.

There are no proven disease specific therapies for peripartum cardiomyopathy, but the use of bromocriptine to suppress the release of prolactin from the pituitary is a consideration for patients with a left ventricular ejection fraction of less than 35%.

In most patients, the left ventricular ejection fraction increases to more than 50% within six months after diagnosis, but in some cardiac function never fully recovers.

A left ventricular assist device or heart transplantation is required it up to 10% of the cases and survival among transplant recipients is inferior to survival among age-adjusted patient’s swho received heart transplants for other reasons.

Overall mortality among patients with peripartum cardiomyopathy can be as high  20% and is higher in low income countries.

Breast-feeding is safe in women with postpartum cardiomyopathy: withholding breast-feeding may increase infant mortality.

The disease occurs in 10-to 50% of patients and recurrence can have worse outcomes, including death.

Lack of recovery of systolic function before the subsequent pregnancy is associated with worse outcome.