Prognostic implication of right ventricular involvement in peripartum cardiomyopathy: a cardiovascular magnetic resonance study

Initial Right Ventricular Dysfunction Severity Identifies Severe Peripartum Cardiomyopathy Phenotype With Worse Early and Overall Outcomes: A 24-Year Cohort Study

BACKGROUND

Outcomes in peripartum cardiomyopathy (PPCM) vary. We sought to determine whether severity of left or right ventricular dysfunction (RVD) at PPCM diagnosis differentially associates with adverse outcomes.

METHODS AND RESULTS

We conducted a single-center retrospective cohort study of 53 patients with PPCM. The primary outcome was a composite of left ventricular assist device implantation, cardiac transplantation, or death. We used Kaplan-Meier curves to examine event-free survival and Cox proportional hazards models to examine associations of left ventricular (LV) ejection fraction <30%, LV end-diastolic diameter ≥60 mm, and moderate-to-severe RVD at PPCM diagnosis with the primary outcome. Median (interquartile range) follow-up time was 3.6 (1.4-7.3) years. Seventeen patients (32%) experienced the primary outcome, of whom 11 had moderate-to-severe RVD at time of PPCM diagnosis. Overall event-free survival differed by initial RVD severity and LV ejection fraction <30%, but not by LV end-diastolic diameter ≥60 mm. In univariable analyses, LV ejection fraction <30% and moderate-to-severe RVD were associated with the outcome (hazard ratios [95% confidence intervals] of 4.85 [1.11-21.3] and 4.26 [1.47-11.6], respectively). In a multivariable model with LV ejection fraction <30%, LV end-diastolic diameter ≥60 mm, and moderate-to-severe RVD, only moderate-to-severe RVD was independently associated with the outcome (hazard ratio [95% confidence interval], 3.21 [1.13-9.10]). Although most outcomes occurred within the first year, nearly a third occurred years after PPCM diagnosis.

CONCLUSIONS

Initial moderate-to-severe RVD is associated with a more advanced cardiomyopathy phenotype and increased risk of adverse outcomes in PPCM, within and beyond the first year of diagnosis. By identifying a worse PPCM phenotype, initial moderate-to-severe RVD may prompt earlier consideration of advanced heart replacement therapies.

Bromocriptine for the Treatment of Peripartum Cardiomyopathy

Peripartum cardiomyopathy (PPCM) is a life-threatening, pregnancy-associated heart disease that develops towards the end of pregnancy or in the first months following delivery in previously healthy women. Understanding of the pathophysiology has progressed in recent years, highlighting an oxidative-stress mediated cleavage of the nursing hormone prolactin into a toxic 16-kDa prolactin fragment as a major factor driving the disease. The 16-kDa prolactin fragment induces detrimental but potentially reversible effects on heart function. Bromocriptine, a clinically-approved drug to block prolactin release, was initially tested in a PPCM mouse model where it efficiently prevented the onset of PPCM. Consequently, this treatment concept was transferred to and successfully used in humans as a bench-tobedside approach. Encouraging proof-of-concept studies led to a randomised trial that further strengthens the role of bromocriptine in addition to standard heart failure therapy in clinical practice. The aim of this article is to summarise this novel and disease-specific medical treatment, along with current knowledge on the epidemiology and pathophysiology of PPCM.

Myocardial Damage Detected by Late Gadolinium Enhancement Cardiac Magnetic Resonance Is Uncommon in Peripartum Cardiomyopathy

BACKGROUND

In peripartum cardiomyopathy, the prevalence of focal myocardial damage detected by late gadolinium enhancement (LGE) cardiovascular magnetic resonance is important to elucidate mechanisms of myocardial injury and cardiac dysfunction. LGE equates irreversible myocardial injury, but LGE prevalence in peripartum cardiomyopathy is uncertain.

METHODS AND RESULTS

Among 100 women enrolled within the Investigations of Pregnancy Associated Cardiomyopathy cohort, we recruited 40 women at 13 centers to undergo LGE cardiovascular magnetic resonance, enrolled within the first 13 weeks postpartum. Follow-up scans occurred at 6 months postpartum, and death/transplant rates at 12 months. Baseline characteristics did not differ significantly in the parent cohort according to cardiovascular magnetic resonance enrollment except for mechanical circulatory support. LGE was noted only in 2 women (5%) at baseline. While left ventricular dysfunction with enlargement was prevalent at baseline cardiovascular magnetic resonance scans (eg, ejection fraction 38% [Q1-Q3 31-50%], end diastolic volume index=108 mL/m² [Q1-Q3 83-134 mL/m²]), most women demonstrated significant improvements at 6 months, consistent with a low prevalence of LGE. LGE was not related to baseline clinical variables, ejection fraction, New York Heart Association heart failure class, or mortality. Neither of the 2 women who died exhibited LGE. LGE was inversely associated with persistent left ventricular ejection fraction at 6 months (P=0.006).

CONCLUSIONS

Factors other than focal myocardial damage detectable by LGE explain the initial transient depressions in baseline left ventricular ejection fraction, yet focal myocardial damage may contribute to persistent myocardial dysfunction and hinder recovery in a small minority. Most women exhibit favorable changes in ventricular function over 6 months.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01085955.

Prognostic implication of right ventricular involvement in peripartum cardiomyopathy: a cardiovascular magnetic resonance study

Aims

Peripartum cardiomyopathy (PPCM) is a major cause of acute heart failure in the peripartum period and considered potentially life threatening. While many aspects of its clinical profiles have been frequently reported, functional analysis, in particular of the right ventricle, and tissue characterization by cardiovascular magnetic resonance (CMR) imaging have been only sporadically described. The aim of the present study was to analyse pathological alterations and their prognostic relevance found in CMR imaging of patients newly diagnosed with PPCM.

Methods and results

In this multicenter study 34 patients with confirmed PPCM underwent CMR imaging at the time of diagnosis and at 5 ± 1 months follow‐up. Cine imaging of PPCM patients showed moderate to severe reduction of systolic left ventricular (LV) function (mean LVEF: 29.7 ± 12.8%). In 35% of the patients right ventricular (RV) systolic function was also reduced with a mean RVEF of 42.9 ± 13.9%. Dilatation of the LV was observed in 91% (mean LV‐EDV/BSA 128.5 ± 32.1 mL/m²), and dilatation of the RV was present in 24% (mean RV‐EDV/BSA 87.4 ± 18.5 mL/m²) of the patients. Focal non‐ischemic late gadolinium enhancement (LGE) was visible in 71%, and regional wall motion abnormalities were evident in 88% of the patients. LGE and wall motion abnormalities were predominantly located in the anteroseptal and basal to midventricular segments. RV dysfunction at baseline was associated with reduced probability of full cardiac recovery at 5 ± 1 months follow‐up.

Conclusions

Besides LV systolic dysfunction, RV dysfunction and dilatation are observed in about one third of PPCM patients at the time of diagnosis. RV dysfunction is associated with unfavourable outcome. A distinct pattern of LV wall motion abnormalities and myocardial scar is evident in most PPCM patients. The present study may help to establish a set of CMR criteria suitable for diagnosis in patients with suspected PPCM and may add further knowledge to the pathology of the disease.