Pregnant and Short of Breath? How to Diagnose Peripartum Cardiomyopathy
A 23 year old G1P1001 presents to the emergency department with several weeks of dyspnea on exertion, fatigue, and palpitations in the context of a recent "stomach flu"-type illness. She endorses vomiting and diarrhea. Two months prior, she had an uncomplicated normal spontaneous vaginal delivery after an uncomplicated pregnancy. Her past medical history is significant for anemia.
Since then, despite attempting to maintain her fluid intake, her symptoms have worsened. At first, she was dyspneic on climbing steps in her home, but now she is dyspneic with minimal movements such as rolling over in bed. She saw her primary care physician once for these symptoms and was told they were probably related to her anemia. She endorses slight pedal swelling over the past few days, L > R, without calf cramping.
She denies history of previous DVT/PE, surgery or lower limb fractures in the past month, active malignancy, unilateral lower extremity pain, hemoptysis, sick contacts, rash, new medications, new exposures, or extremity paresthesias.
Vitals: HR 132, RR 26, BP 123/74, O2 100% RA, T 37.1 PO.
Physical Exam: She is fatigued and tachypneic but without tripoding. She speaks in full sentences. She has dry mucous membranes, trace pedal edema L > R, no calf tenderness, and clear lungs without crackles or wheezing.
Bedside echo: poor ejection fraction, non-dilated right ventricle.
EKG: sinus tach 137 without ischemic changes.
Dilated cardiomyopathy with concomitant heart failure (most likely)
Hypovolemia secondary to GI losses.
Pt was admitted to the Cardiac Acute Care Unit when formal echo showed an EF of 20-25%.
It is actually peripartum, not postpartum cardiomyopathy. It is the development of systolic HF (EF < 45% with or without left ventricular dilation) from late pregnancy through 5 months postpartum (usually not before 36 weeks gestation and not after 1 month postpartum).
Usually there is no other identifiable cause of heart failure
Unknown, probably multifactorial
What we do know are the risk factors:
Long-term tocolytic beta agonist use (i.e. terbutaline)
Rare: 1/15,000 pregnancies
Fatal in 50%; survivors often have exercise impairment and may require transplant
HF: dyspnea, cough, orthopnea, paroxysmal nocturnal dyspnea, lower extremity edema, fatigue, S3, mitral regurgitation murmur
Confounder: these are also pregnancy symptoms
Venous thromboembolism...since this diagnosis is also associated with LV thrombus
Accelerated HTN, diastolic HF, systemic infection, PE, other complications of late pregnancy (preeclampsia/amniotic fluid embolus), ischemia
Echo is the most important diagnostic test
Sometimes: LV/LA dilation/thrombus, RV dilation/hypokinesis, mitral or triscuspid regurgitation, small effusion
BNP: can be elevated in pregnancy already
EKG: nonspecific changes, usually sinus tach and rarely atrial fibrillation, sometimes anterior Qs
More helpful in finding ischemia as a mimic
CXR: heart failure changes... but not necessary to make the diagnosis
Pre-existing cardiomyopathy: idiopathic, familial, HIV/AIDS
Pre-existing valvular disease: mitral stenosis/regurgition, aortic stenosis/regurgitation
Pre-existing congenital heart disease: ASD, VSD, PDA
Diastolic heart failure secondary to HTN
Heart failure management
Optimize both preload and afterload
Manage arrhythmias: a-fib is common
Anticoagulation? This pt has a high risk of VTE... but data is inconclusive: Does antiplatelet/anticoagulant agents help reduce clotting events or mortality in patients who are in sinus rhythm? This is a more complex decision, especially if the patient is still pregnant
LV systolic disfunction without LV thrombus or another indication for anticoagulation: Don’t do it.
Otherwise: May consider it
Hemodynamic/mechanical support: inotropes and pressors PRN. Additionally some end up with ICDs, but 20-60% of pts recover EF by 6 months to 5 years.
Consider it sooner if hemodynamically unstable or maxed out on inotropes
Some need IABP, VA ECMO, LVAD, transplant
Know the window of time when symptoms present: Late pregnancy through 5 months postpartum. Make sure to ask female patients of childbearing age her OB history.
The echo is essential. Try to find intra-cardiac thrombi or valvular disease if you can.
Treat it like heart failure. Pay special attention to arrhythmias and hemodynamic instability (you may need inotropes/pressors).
Sonika Raj MD, MS is a current third year resident at Stony Brook Emergency Medicine.
Edited by Bassam Zahid, MD