Outcomes of PPCM
Prognosis of PPCM is positively related to the recovery of ventricular function. Failure of heart size to return to normal is associated with increased mortality and morbidity. Women with persistent left ventricular dysfunction are less likely to survive and recover normal cardiac function than are women with improved left ventricular function. A fractional shortening less than 20% and a left ventricular diastolic dimension of 6 cm or greater at the time of diagnosis are associated with a more than 3-fold higher risk for persistent cardiac dysfunction. Sliwa et al found that ejection fraction was the strongest predictor of outcome in women with PPCM. Abboud et al reported that 50% of women with PPCM recover baseline ventricular function within 6 months of delivery. In contrast, Ntusi and Mayosi found that only 30% of women with PPCM have complete recovery of cardiac function; most have partial recovery. Medical therapy as outlined in the ACCF/AHA guidelines should be continued when a woman does not recover function. When appropriate, implantation of defibrillators to prevent sudden cardiac death and use of cardiac revascularization therapy should be considered.
Reported mortality rates for PPCM vary widely. In a study by Sliwa et al, the mortality rate in 29 women was 32%, whereas in a large population-based study in Haiti by Fett et al, the mortality rate was 15.8%. In a study of 123 women by Elkayam et al, the rate was 9% at a mean follow-up time of 24 months. Brar et al concluded that mortality rates associated with PPCM were lower than initially reported at 2.5%, and Mielniczuk et al reported a mortality rate of 1.36% to 2.05%. Earlier diagnosis, coupled with modern management of heart failure, most likely has an important influence on the mortality associated with PPCM. Although rates have improved, mortality remains extremely high in women with PPCM.
One of the most frequently cited issues for women who survive PPCM is whether or not they can safely become pregnant again. No clearly established recommendations for future pregnancies in these women exist. Left ventricular recovery and function are considered the most reliable prognostic factors and predictors of survival in subsequent pregnancies. Future pregnancies are not recommended in women with persistent heart failure, because the heart most likely would not be able to puertolerate the increased cardiovascular workload associated with the pregnancy. Women whose cardiomyopathy appears to have resolved are a more difficult group to counsel. Because multiparity has been associated with PPCM, subsequent pregnancies can increase the risk for recurrent episodes of PPCM, irreversible cardiac damage and decreased left ventricular function, worsening of a woman's clinical condition, and even death.
Williams et al have suggested that dividing women into 2 categories (recovered vs nonrecovered left ventricular function) is most appropriate for counseling on future pregnancy. Even though the cardiac function has normalized in the group of women with recovered cardiac function, the left ventricular contractile reserve may remain impaired, and recurrence of PPCM is still possible. The subset of women with persistent left ventricular systolic dysfunction should be counseled against subsequent pregnancies; the risks are 19% higher for maternal death than among women with PPCM whose heart failure has resolved.