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Continued part 1, part 2 of ebook Medical disorders in pregnancy provide readers with content about: new insights in peripartum cardiomyopathy; gestational diabetes: underpinning principles, surveillance, and management; pregestational diabetes in pregnancy; hypertensive disorders in pregnancy; seizures in pregnancy;... Please refer to the part 2 of ebook for details!
N e w I n s i g h t s in P e r i p a r t u m C a rd i o m y o p a t h y Meredith O Cruz, MD, MPH, MBA a, *, Joan Briller, MD b,c , Judith U Hibbard, MD a KEYWORDS Peripartum cardiomyopathy Pregnancy Cardiac disease Congestive heart failure KEY POINTS Specific diagnostic criteria should be used to diagnose peripartum cardiomyopathy (PPCM), but this is a diagnosis of exclusion Although rare, PPCM is a leading cause of maternal mortality Significant advances have been made in understanding PPCM pathophysiology, especially hormonal and genetic mechanisms Long-term and recurrent pregnancy prognosis depends on recovery of cardiac function INTRODUCTION Peripartum cardiomyopathy (PPCM), or heart failure (HF) associated with pregnancy, was first described in 1937.1 The syndrome was poorly defined until 1971 when specifically noted as occurring in the peripartum period.2 Hibbard and colleagues3 included echocardiographic (ECHO) criteria for PPCM in 1999, stressing reduced ejection fraction (EF 30 mL/ and K1 1 year, implantable cardioverter defibrillators may be warranted for primary prevention of sudden cardiac death.60 Relatively high rate of recovery in PPCM should be considered before a defibrillator is placed Moreover, delayed recovery after months is reported in a significant minority of patients, which may modify the decision for placement.61 Women should have received a minimum of months of GDMT with b-blockers and ACEIs before deciding.60 Wearable cardiac defibrillators have been used successfully for primary prevention in anticipation of ventricular function recovery, especially with high-risk features.62 Cardiac resynchronization therapy is recommended for some patients.60 LV assist devices (LVADs) and transplantation are therapeutic options in the most critical patients, with the former associated with subsequent improvement of ventricular function in a few patients.45,63 Impact of breastfeeding on outcomes has been controversial, especially given the proposed role of prolactin in disease development.50,64,65 Fear of adverse effects of medication transmission to the child via breast milk or increased hemodynamic demands of lactation in sick women sometimes lead to recommendations to discontinue lactation Fifteen percent of women in the IPAC registry breastfed.64 No effect was seen on myocardial recovery at 12 months In a retrospective review of PPCM women recruited via the Internet, 67.3% of women breastfed, and this was associated with increased recovery.65 However, it is unknown if women had better initial EFs or other reasons for improved survival Other Novel Therapies In mouse models, proapoptotic fragments of prolactin lead to myocardial injury.27,28 Bromocriptine stimulates hypothalamic dopaminergic receptors inhibiting prolactin 289 290 Cruz et al secretion, suggesting theoretic treatment benefit.66 A randomized controlled trial with bromocriptine as adjunctive therapy in 20 South African women showed improved ventricular recovery as proof of concept, although adverse outcomes in the control group were high.67 A nonrandomized German registry found bromocriptine use twice as common in women with improved LV function, although the percentage of women receiving advanced HF interventions in both groups was similar.68 A recent multicenter trial of 63 PPCM patients with EFs less than 35% randomized women to week or weeks of bromocriptine therapy.69 No patient required advanced HF interventions or died There was a nonsignificant trend toward greater recovery in the 8-week therapy group, but both groups showed improvement Therapy was well tolerated A major limitation to the study was lack of a placebo control group An accompanying editorial suggested that bromocriptine could be added to usual GDMT.70 Small numbers of patients, validity of comparing outcomes to a historical control groups with large numbers of AAs who have worse outcomes, concerns about potential hypertensive or thrombotic complications with bromocriptine treatment, and loss of ability to lactate in treated women, especially in developing countries, are among the reasons dampening enthusiasm for widespread use in the United States in the absence of a placebo-controlled trial.6 When bromocriptine is used, patients should receive concomitant anticoagulant therapy.69 Although approved for other indications, bromocriptine is not currently approved for treatment of PPCM in the United States Evidence regarding treatment with intravenous immune globulin has been inconsistent.71,72 A South African study demonstrated improved outcomes in PPCM women treated with pentoxyfylline Tumor necrosis factor-a levels decreased in patients and controls, but there was greater survival, EF improvement, and NYHA class in the pentoxyfilline group.73 A randomized trial of Levosimendan, a calcium sensitizer, in 24 women with PPCM showed no difference in clinical or outcomes.74 GDMT should continue with persistent LV dysfunction There are no well-controlled studies to advise duration of therapy when LV function improves, but most experts recommend continuing for months after recovery.6,75 Ivabradine could be discontinued first, followed by aldosterone antagonists before downtitration of ACEIs or b-blockers, observing for recurrence.75 Management of Delivery Most women present postpartum, but for women who present during pregnancy, it is not known if early delivery will diminish progression of LV dysfunction.6 Timing and mode of delivery decisions are best made by a team approach, including the maternal fetal medicine, cardiology, obstetric-anesthesia, and neonatology providers caring for the patient Labor is not contraindicated for stable patients Administration of steroids to promote fetal lung maturity can increase fluid retention.45 In the authors’ practice, labor induction can be conducted with minimal risk; cervical ripening with prostaglandins and oxytocin can be administered safely Early epidural will minimize sympathetic output however, but caution must be exercised with fluid boluses to avoid overload.51 Shortening the second stage of labor and the use of low-forceps or vacuum device will also decrease cardiac work.76 Given the surgical risks encountered with cesarean delivery, such as infection, blood loss, fluid shifts, and postoperative complications, the authors believe cardiovascular benefits from vaginal delivery most often outweigh that of surgical delivery The authors reserve cesarean delivery for obstetric indications; however, need for prompt delivery may influence the decision Placement of a pulmonary artery catheter for hemodynamic monitoring is rarely recommended,50 but strict monitoring of fluid status is critical The authors often administer diuretics after delivery in the absence of bleeding to prevent volume overload ... Hypotension Inotropes DigoxinL2 [ Myocontractility Arrhythmias Gastrointestinal symptoms Narrow therapeutic index Arrhythmias Hypotension with dobutamine and milrinone Dopaminec,L2 Dobutaminec,L2 Milrinonec,L4... occurring peripartum coinciding with the peak incidence of PPCM.6 Both prolactin and soluble FMs-like tyrosine kinase-1 (sFlt1) have been implicated in PPCM pathogenesis .27 ,28 An imbalance in angiogenic... heparin or continuous unfractionated heparin during pregnancy depending on whether antepartum or intrapartum, along with warfarin postpartum All agents are compatible with breastfeeding. 52 There