What 2D echo findings suggest postpartum cardiomyopathy (PPCM) in a patient?

2D Echocardiography Findings in Postpartum Cardiomyopathy

The primary 2D echo finding that defines postpartum cardiomyopathy is a left ventricular ejection fraction (LVEF) <45%, with or without left ventricular dilatation. 1, 2

Core Diagnostic Echocardiographic Criteria

Systolic Dysfunction Parameters:

• LVEF <45% is the essential diagnostic criterion required for PPCM diagnosis 1, 2
• Fractional shortening <30% serves as an alternative measure of systolic dysfunction 1, 3
• These parameters nearly always show reduction below the 45% threshold in PPCM 1

Ventricular Dimensions:

• LV end-diastolic dimension >2.7 cm/m² body surface area is part of formal diagnostic criteria, though not required for diagnosis 1, 3
• LV end-diastolic diameter >60 mm indicates poor prognosis and predicts failure to recover 2, 4
• Important caveat: The left ventricle may NOT be dilated in PPCM—absence of dilatation does not exclude the diagnosis 1, 2

Additional Structural Findings

Chamber and Valve Abnormalities:

• Four-chamber enlargement is commonly observed 1
• Mitral regurgitation is present in approximately 43% of patients 1, 2
• Tricuspid regurgitation may be present 1
• Biatrial enlargement is frequently seen 1
• Right ventricular enlargement occurs in approximately 24% of cases 1, 5

Right Ventricular Involvement:

• RV systolic dysfunction is present in approximately 35% of PPCM patients, with mean RVEF of 42.9 ± 13.9% 5
• RV dilatation (RV end-diastolic volume/BSA >87.4 mL/m²) occurs in about one-quarter of patients 5
• RV dysfunction at baseline predicts reduced probability of full cardiac recovery 5

Prognostic Echocardiographic Features

High-Risk Parameters:

• LVEF <30% at presentation strongly predicts poor recovery of ventricular function 2, 4
• LVEF <34% is an independent prognostic factor for persistent LV systolic dysfunction (95% CI, 1.38-7.30; P = 0.007) 4
• LV end-diastolic diameter >60 mm is associated with worse outcomes and failure to recover 2
• LV end-diastolic diameter ≥64 mm predicts persistent dysfunction 4

Volume Parameters:

• LV end-diastolic volume index of 95 ± 22 ml/m² (compared to 67 ± 9 ml/m² in normal postpartum women) indicates marked LV dilatation 6
• LV end-systolic volume index of 66 ± 18 ml/m² (versus 27 ± 5 ml/m² in controls) reflects severe systolic impairment 6

Critical Complications to Assess

Thrombus Formation:

• LV thrombus is not uncommon when LVEF <35% 1, 2
• Echocardiography is essential for ruling out LV thrombus, particularly when LVEF is severely depressed 2
• Common pitfall: Failure to screen for LV thrombus in patients with LVEF <35% carries significant embolic risk, including cerebral, coronary, and mesenteric embolism 1, 2

Elevated Pressures:

• Elevated pulmonary artery pressures are frequently present 1

Regional Wall Motion Abnormalities

• Regional wall motion abnormalities are evident in 88% of PPCM patients 5
• These abnormalities are predominantly located in the anteroseptal and basal to midventricular segments 5

Timing of Echocardiographic Assessment

Serial Evaluation Protocol:

• Initial echocardiography should be performed immediately when PPCM is suspected 2
• Repeat assessments should occur before patient discharge, at 6 weeks, 6 months, and annually to evaluate treatment efficacy and recovery 2
• Early improvement in LV function occurs in approximately 93% of patients (13 of 14), following an exponential time course during LV remodeling 6

Key Diagnostic Pitfalls to Avoid

Do Not Exclude PPCM Based on:

• Absence of LV dilatation—the ventricle may not be dilated, but LVEF is nearly always reduced below 45% 1, 2
• Normal LV dimensions—systolic dysfunction (LVEF <45%) is the defining feature, not chamber size 1, 2

Must Screen For:

• LV thrombus in all patients with LVEF <35% to prevent catastrophic embolic complications 1, 2
• RV dysfunction, as it predicts unfavorable outcomes and reduced probability of recovery 5

Distinguishing Features from Other Conditions

Versus Pre-existing Dilated Cardiomyopathy:

• Pre-existing idiopathic or familial dilated cardiomyopathy typically presents with larger cardiac dimensions than PPCM 2, 7
• Pre-existing cardiomyopathy usually manifests by the 2nd trimester rather than postpartum 2, 7

Versus HIV Cardiomyopathy:

• HIV cardiomyopathy often presents with non-dilated ventricles 2