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Cardiomyopathy, Peripartum, Emergency Medicine

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Cardiomyopathy, Peripartum, Emergency Medicine

Basics

Description

Various causes are suggested but remain unproved:

674.54 Peripartum cardiomyopathy, postpartum condition or complication

  • Dilated cardiomyopathy occurring during the last month of pregnancy up to 5 mo following the delivery
  • Diagnostic criteria (all required):Onset of myocardial failure during last month of pregnancy or 1st 5 mo after deliveryAbsence of a specific causeAbsence of prior cardiac disease
  • Diagnosis requires strict criteria of echocardiographic dysfunction
  • Incidence: 3-5/10,000 live births
  • ~50% of cases resolve spontaneously
  • Mortality: 18-56%
  • Risk factors:Older women (>30 yr)Multiparous womenMultiple gestationsProlonged tocolytic therapy (>4 wk)ObesityPreeclampsiaAfrican American
  • Systemic and pulmonary embolism more frequent than with other forms of cardiomyopathy
  • Factors indicating a poor prognosis:Lower left ejection fraction at 6 mo postpartumOnset >2 wk postpartumAge >30 yrAfrican American descentMultiparity
  • Onset of myocardial failure during last month of pregnancy or 1st 5 mo after delivery
  • Absence of a specific cause
  • Absence of prior cardiac disease
  • Older women (>30 yr)
  • Multiparous women
  • Multiple gestations
  • Prolonged tocolytic therapy (>4 wk)
  • Obesity
  • Preeclampsia
  • African American
  • Lower left ejection fraction at 6 mo postpartum
  • Onset >2 wk postpartum
  • Age >30 yr
  • African American descent
  • Multiparity

Etiology

  • Viral infection leading to myocarditis in presence of immunosuppression during pregnancy (most likely)
  • Immunologic response to an unknown maternal or fetal antigen
  • Maladaptive response to the hemodynamic stresses of pregnancy
  • Stress-activated cytokines
  • Prolonged tocolysis
  • Selenium deficiency

Diagnosis

Signs and Symptoms

  • Dyspnea
  • Dizziness
  • Chest pain
  • Orthopnea
  • Cough
  • Paroxysmal nocturnal dyspnea
  • Anorexia
  • Fatigue
  • Arrhythmias
  • Onset and duration of symptoms
  • Unexplained persistent cough
  • Excessive weight gain:>2-4 lb/wk
  • Prior cardiac disease
  • Prior pregnancies and complications
  • >2-4 lb/wk
  • Palpitations
  • Jugular venous distention
  • Gallop rhythm
  • Mitral regurgitation murmur
  • Loud P2
  • Pulmonary rales
  • Peripheral edema (especially rapid onset)
  • Hepatomegaly
  • Hepatojugular reflux

Essential Workup

  • CXR views:Pulmonary venous congestionCardiomegaly (can be difficult to differentiate with pregnancy)Pleural effusions
  • EKG:NonspecificLeft ventricular hypertrophyLeft atrial enlargementT-wave flattening or inversionArrhythmiasVentricular ectopy (40%)Atrial fibrillation (20%)
  • Pulmonary venous congestion
  • Cardiomegaly (can be difficult to differentiate with pregnancy)
  • Pleural effusions
  • Nonspecific
  • Left ventricular hypertrophy
  • Left atrial enlargement
  • T-wave flattening or inversion
  • Arrhythmias
  • Ventricular ectopy (40%)
  • Atrial fibrillation (20%)

Diagnosis Tests & Interpretation

  • Electrolytes:Generally normal
  • BUN, creatinine
  • CBC:Mild postpartum anemia may contribute to fatigue and dyspnea.
  • Creatine kinase with muscle and brain fraction
  • β-Natriuretic peptide (BNP):Useful for distinguishing between heart failure due to diastolic and/or systolic dysfunction and a pulmonary cause of dyspneaBNP >100 pg/mL diagnosed heart failure with a sensitivity of 90%, a specificity of 76%, and a predictive accuracy of 83%. BNP of ≤50 pg/mL has a high negative predictive value.
  • Generally normal
  • Mild postpartum anemia may contribute to fatigue and dyspnea.
  • Useful for distinguishing between heart failure due to diastolic and/or systolic dysfunction and a pulmonary cause of dyspnea
  • BNP >100 pg/mL diagnosed heart failure with a sensitivity of 90%, a specificity of 76%, and a predictive accuracy of 83%. BNP of ≤50 pg/mL has a high negative predictive value.
  • CXR:CardiomegalyEffusions (usually right sided)3 phases of pulmonary findings:Stage I: Pulmonary redistribution to upper lung fields (cephalization)Stage II: Interstitial edema with Kerley B linesStage III: Alveolar edemaBilateral confluent perihilar infiltrates leading to classic butterfly patternMay be asymmetric and mistaken for pneumonia
  • Echo:Demonstrates global dilation, cardiac wall thinning, and decreased ejection fractionCriteria for the diagnosis were established by Hibbard et al.:Ejection fraction <45% or M-mode fractional shortening of <30%End-diastolic dimension >2.72 cm/m2Exclude valvular pathology and cardiac tamponade.
  • Cardiomegaly
  • Effusions (usually right sided)
  • 3 phases of pulmonary findings:Stage I: Pulmonary redistribution to upper lung fields (cephalization)Stage II: Interstitial edema with Kerley B linesStage III: Alveolar edemaBilateral confluent perihilar infiltrates leading to classic butterfly patternMay be asymmetric and mistaken for pneumonia
  • Stage I: Pulmonary redistribution to upper lung fields (cephalization)
  • Stage II: Interstitial edema with Kerley B lines
  • Stage III: Alveolar edema
  • Bilateral confluent perihilar infiltrates leading to classic butterfly pattern
  • May be asymmetric and mistaken for pneumonia
  • Demonstrates global dilation, cardiac wall thinning, and decreased ejection fraction
  • Criteria for the diagnosis were established by Hibbard et al.:Ejection fraction <45% or M-mode fractional shortening of <30%End-diastolic dimension >2.72 cm/m2
  • Exclude valvular pathology and cardiac tamponade.
  • Ejection fraction <45% or M-mode fractional shortening of <30%
  • End-diastolic dimension >2.72 cm/m2
  • Indicated to assess for myocarditis and steroid therapy

Differential Diagnosis

  • Other causes of dilated cardiomyopathy:IschemiaInfarctionValvular rupture or diseaseChronic HTNFamilialToxins:Ethanol, anthracyclines, cocaine, drug allergyMetabolic:ThiamineSeleniumHypothyroidismThyrotoxicosisHypophosphatemiaInfectious:ViralParasitic or rickettsialBacterialFungalSystemic disorders:SarcoidosisSclerodermaSystemic lupus erythematosusEosinophilic myocarditisNeuromuscular dystrophiesMitochondrial cardiomyopathies
  • Other causes of shortness of breath or edema:Pulmonary embolismPneumoniaAsthmaCardiac ischemiaAnemiaHyperthyroidismConstrictive pericarditisPericardial tamponadeNephrotic syndromeCirrhosis
  • Ischemia
  • Infarction
  • Valvular rupture or disease
  • Chronic HTN
  • Familial
  • Toxins:Ethanol, anthracyclines, cocaine, drug allergy
  • Metabolic:ThiamineSeleniumHypothyroidismThyrotoxicosisHypophosphatemia
  • Infectious:ViralParasitic or rickettsialBacterialFungal
  • Systemic disorders:SarcoidosisSclerodermaSystemic lupus erythematosus
  • Eosinophilic myocarditis
  • Neuromuscular dystrophies
  • Mitochondrial cardiomyopathies
  • Ethanol, anthracyclines, cocaine, drug allergy
  • Thiamine
  • Selenium
  • Hypothyroidism
  • Thyrotoxicosis
  • Hypophosphatemia
  • Viral
  • Parasitic or rickettsial
  • Bacterial
  • Fungal
  • Sarcoidosis
  • Scleroderma
  • Systemic lupus erythematosus
  • Pulmonary embolism
  • Pneumonia
  • Asthma
  • Cardiac ischemia
  • Anemia
  • Hyperthyroidism
  • Constrictive pericarditis
  • Pericardial tamponade
  • Nephrotic syndrome
  • Cirrhosis

Treatment

Pre-Hospital

Initial Stabilization/Therapy

  • Prompt evaluation of respiratory and hemodynamic status
  • Control airway as needed
  • Supplemental oxygen
  • Continuous positive airway pressure, as needed
  • Preload and afterload reduction

Ed Treatment/Procedures

  • Antepartum therapy:NitratesHydralazineIV furosemideAmlodipine: A dihydropyridine calcium channel blocker that has been shown to improve survival in nonischemic cardiomyopathy patientsDigoxin to control rate due to atrial fibrillationCarvedilol (antepartum and not in acute decompensated phase)LMWH if EF <35%Fetal monitoring
  • Invasive cardiac monitoring if unstable
  • Postpartum therapy:Consider adding ACE inhibitors (enalapril) or ARBs.Anticoagulation therapy often recommended:30% of cases complicated by systemic or pulmonary embolismDuring pregnancy, use SC or IV heparin rather than warfarin, which causes birth defects.
  • For severe symptoms or lack of response to standard therapy:DobutamineDopamineNitroprussideAssist devicesIntra-aortic balloon pumpLV assist deviceExtracorporeal membrane oxygenationImmunosuppressive therapy:Advocated for patients who fail to improve within 2 wk of standard medical therapyPrednisone with cyclosporine or azathioprineImmunoglobulin therapy remains controversial
  • Nitrates
  • Hydralazine
  • IV furosemide
  • Amlodipine: A dihydropyridine calcium channel blocker that has been shown to improve survival in nonischemic cardiomyopathy patients
  • Digoxin to control rate due to atrial fibrillation
  • Carvedilol (antepartum and not in acute decompensated phase)
  • LMWH if EF <35%
  • Fetal monitoring
  • Consider adding ACE inhibitors (enalapril) or ARBs.
  • Anticoagulation therapy often recommended:30% of cases complicated by systemic or pulmonary embolismDuring pregnancy, use SC or IV heparin rather than warfarin, which causes birth defects.
  • 30% of cases complicated by systemic or pulmonary embolism
  • During pregnancy, use SC or IV heparin rather than warfarin, which causes birth defects.
  • Dobutamine
  • Dopamine
  • Nitroprusside
  • Assist devicesIntra-aortic balloon pumpLV assist deviceExtracorporeal membrane oxygenation
  • Immunosuppressive therapy:Advocated for patients who fail to improve within 2 wk of standard medical therapyPrednisone with cyclosporine or azathioprineImmunoglobulin therapy remains controversial
  • Intra-aortic balloon pump
  • LV assist device
  • Extracorporeal membrane oxygenation
  • Advocated for patients who fail to improve within 2 wk of standard medical therapy
  • Prednisone with cyclosporine or azathioprine
  • Immunoglobulin therapy remains controversial

Medication

  • Amlodipine: 2.5-10 mg/d PO
  • Bumetanide: 0.5-2 mg IV
  • Digoxin: 0.5 mg IV, then 0.25 mg IV q4h for 2 doses; 0.125-0.375 mg/d PO
  • Milrinone: 50 μg/kg over 10 min
  • Dobutamine: 2-10 μg/kg/min IV
  • Dopamine: 2-20 μg/kg/min IV
  • Enalapril: 0.625-1.25 mg IV; 2.5-20 mg/d PO
  • Furosemide: 20-100 mg IV
  • Metoprolol: 12.5 mg PO BID
  • Morphine sulfate: 2-4 mg IV q5min
  • Nitroglycerin: 0.4 mg sublingual; 1-2 in of nitroglycerin paste; 5-20 μg/min IV, max. of 100-200 μg/min IV. USE NON-PVC tubing
  • Nitroprusside: 0.5-10 μg/kg/min IV

Follow-Up

Disposition

  • Patients with pulmonary edema, cardiogenic shock, or evidence of ischemia should be admitted to the ICU.
  • All symptomatic patients with new onset of peripartum cardiomyopathy should be admitted.
  • Mild left ventricular dysfunction
  • Established history of peripartum cardiomyopathy:Mild fluid overload attributable to excessive salt intakeComplete resolution of symptoms following ED treatmentNo evidence of cardiac ischemia
  • Close follow-up arranged
  • Mild fluid overload attributable to excessive salt intake
  • Complete resolution of symptoms following ED treatment
  • No evidence of cardiac ischemia

Follow-Up Recommendations

  • Drink 6-8 glasses of liquid each day.
  • Limit salt intake.
  • Avoid alcohol because it may worsen cardiomyopathy.
  • Support socks may help decrease the swelling in legs and prevent clot formation.
  • Daily weights:Weight gain can be a sign of extra fluid in the body.Call doctor if gain of >2 lb in a day.
  • Return for shortness of breath, feeling faint, palpitations.
  • Weight gain can be a sign of extra fluid in the body.
  • Call doctor if gain of >2 lb in a day.

Pearls and Pitfalls

  • Remember high rates of thromboembolism in pregnancy and peripartum cardiomyopathy.
  • Utilize multidisciplinary approach with cardiology and obstetrics consultations.

Additional Reading

  • Johnson-Coyle L, Jensen L, Sobey A. Peripartum cardiomyopathy: Review and practice guidelines. Am J Crit Care. 2012;21(2):89-98.
  • Murali S, Baldisseri MR. Peripartum cardiomyopathy. Crit Care Med. 2005;33:S340-S346.
  • Pearson GD, Veille JC, Rahimtoola S, et al. Peripartum cardiomyopathy: National Heart, Lung, and Blood Institute and Office of Rare Diseases (National Institutes of Health) workshop recommendations and review. JAMA. 2000;283:1183-1188.
  • Ramaraj R, Sorrell VL. Peripartum cardiomyopathy: Causes, diagnosis, and treatment. Cleve Clin J Med 2009;76(5):289-296.
  • Tidswell M. Peripartum cardiomyopathy. Crit Care Clin. 2004;20:777-788.

Codes

ICD9

ICD10

SNOMED

  • 62377009 Postpartum cardiomyopathy (disorder)