Clinical Outcomes for Peripartum Cardiomyopathy in North America: Results of the IPAC Study (Investigations of Pregnancy-Associated Cardiomyopathy)

Abstract

Background: Peripartum cardiomyopathy (PPCM) remains a major cause of maternal morbidity and mortality.

Objectives: This study sought to prospectively evaluate recovery of the left ventricular ejection fraction (LVEF) and clinical outcomes in the multicenter IPAC (Investigations of Pregnancy Associated Cardiomyopathy) study.

Methods: We enrolled and followed 100 women with PPCM through 1 year post-partum. The LVEF was assessed by echocardiography at baseline and at 2, 6, and 12 months post-partum. Survival free from major cardiovascular events (death, transplantation, or left ventricular [LV] assist device) was determined. Predictors of outcome, particularly race, parameters of LV dysfunction (LVEF), and remodeling (left ventricular end-diastolic diameter [LVEDD]) at presentation, were assessed by univariate and multivariate analyses.

Results: The cohort was 30% black, 65% white, 5% other; the mean patient age was 30 ± 6 years; and 88% were receiving beta-blockers and 81% angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. The LVEF at study entry was 0.35 ± 0.10, 0.51 ± 0.11 at 6 months, and 0.53 ± 0.10 at 12 months. By 1 year, 13% had experienced major events or had persistent severe cardiomyopathy with an LVEF <0.35, and 72% achieved an LVEF ≥0.50. An initial LVEF <0.30 (p = 0.001), an LVEDD ≥6.0 cm (p < 0.001), black race (p = 0.001), and presentation after 6 weeks post-partum (p = 0.02) were associated with a lower LVEF at 12 months. No subjects with both a baseline LVEF <0.30 and an LVEDD ≥6.0 cm recovered by 1 year post-partum, whereas 91% with both a baseline LVEF ≥0.30 and an LVEDD <6.0 cm recovered (p < 0.00001).

Conclusions: In a prospective cohort with PPCM, most women recovered; however, 13% had major events or persistent severe cardiomyopathy. Black women had more LV dysfunction at presentation and at 6 and 12 months post-partum. Severe LV dysfunction and greater remodeling at study entry were associated with less recovery. (Investigations of Pregnancy Associated Cardiomyopathy [IPAC]; NCT01085955).

Keywords: heart failure; myocardial recovery; race; remodeling.

FIGURE 1. Event Rate by Baseline LVEF

The percentage of women who died or underwent LVAD implantation during the first year post-partum. Dashed blue line = women with an initial LVEF ≥0.30; solid red line = women with an initial LVEF <0.30. The event rate was significantly higher in women with an LVEF <0.30, p = 0.004. LVAD = left ventricular assist device; LVEF = left ventricular ejection fraction.

FIGURE 2. LVEF Over Time Post-Partum

(A) Overall cohort. LVEF at study entry, 6, and 12 months post-partum for the entire cohort. (B) By race. The LVEF was significantly poorer in black women with PPCM at study entry (p = 0.009), 6 months (p = 0.006), and 12 months post-partum (p = 0.001). LVEF = left ventricular ejection fraction; PPCM = post-partum cardiomyopathy.

FIGURE 3. Initial LVEF and LVEDD and LVEF Over Time

(A) Initial LVEF <0.30 or ≥0.30. In women with severe LV dysfunction at study entry, poorer LV function persists at 6 months (p < 0.001) and 12 months (p < 0.001) postpartum. (B) Initial LVEDD <6.0 or ≥6.0 cm. Women with greater LV remodeling at entry (LVEDD ≥6.0 cm) demonstrate a lower LVEF at study entry (p = 0.04) and less recovery at 6 months (p < 0.001) and 12 months (p < 0.001) post-partum. LV = left ventricular; LVEDD = left ventricular end-diastolic diameter.

FIGURE 4. Final Status Based on the Initial LVEF

Comparison of status at the end of the study based on the initial LVEF. Red column, percentage of women with no recovery (event or final LVEF <0.35); blue column, percentage of women with partial recovery (final LVEF 0.35 to 0.49); purple column, percentage of women with complete recovery (LVEF ≥0.50). Recovery was evident in 86% of women with a baseline LVEF ≥0.30, compared with 37% of those with an LVEF <0.30, p < 0.001. LVEF = left ventricular ejection fraction.

CENTRAL ILLUSTRATION. Myocardial Recovery and Outcomes in Peripartum Cardiomyopathy: Baseline LVEF, Race, and 12-Month Outcome—Absolute LVEF and Change in LVEF From Baseline

(A) Absolute LVEF at 12 months. The y-axis shows the LVEF at 12 months; the baseline LVEF is shown on the x-axis. A significant association was seen in blacks (p < 0.005) but not in whites and others (p = 0.44). (B) Change in LVEF from baseline to 12 months. The change in LVEF is shown on the y-axis and baseline LVEF is shown on the x-axis. A significant association was seen in whites and others (p < 0.0001) but not in blacks (p = 0.68). LVEF = left ventricular ejection fraction.