Does a reversal of the transmitral E/A flow indicate diastolic dysfunction?

E/A Reversal and Diastolic Dysfunction

E/A reversal (E/A <1) indicates impaired left ventricular relaxation, which represents Grade I diastolic dysfunction, but it does NOT automatically mean clinically significant diastolic dysfunction or elevated filling pressures 1.

Understanding E/A Reversal in Context

The E/A ratio alone is insufficient to diagnose diastolic dysfunction because:

• Normal aging causes E/A reversal - Healthy elderly individuals commonly show E/A <1 due to age-related slowing of LV relaxation, mimicking mild diastolic dysfunction seen in younger patients 1
• E/A reversal represents only ONE stage in the spectrum of diastolic dysfunction
• Loading conditions heavily influence the E/A ratio, making it unreliable as a standalone measure

The Diastolic Dysfunction Spectrum

When diastolic dysfunction progresses, the E/A ratio follows a characteristic pattern 1:

1. Grade I (Impaired Relaxation): E/A <1 with normal filling pressures

   • Prolonged deceleration time
   • Prolonged IVRT
   • This is what E/A reversal typically indicates

2. Grade II (Pseudonormal): E/A appears normal (0.8-1.5) BUT filling pressures are elevated

   • Critical pitfall: Looks normal but represents worsening disease
   • Can be unmasked with Valsalva maneuver (E/A decreases ≥50%) 1

3. Grade III (Restrictive): E/A >2 with markedly elevated filling pressures

   • Shortened deceleration time (<150 msec)
   • Associated with poor prognosis 2

What You Actually Need to Diagnose Diastolic Dysfunction

The 2016 ASE/EACVI guidelines require a multiparametric approach 1:

Essential Additional Parameters:

• E/e' ratio: Average E/e' >14 indicates elevated filling pressures (more reliable than E/A alone)
• LA volume index: >34 mL/m² suggests chronically elevated pressures
• Peak TR velocity: >2.8 m/sec indicates elevated pulmonary pressures
• Pulmonary vein flow: Ar-A duration ≥30 msec suggests elevated LVEDP

The Algorithm:

1. Measure E/A ratio AND septal/lateral e' velocities
2. Calculate average E/e' ratio
3. Assess LA volume index
4. Measure TR velocity if present
5. If ≥3 of 4 criteria are positive (E/e' >14, LA volume >34 mL/m², TR velocity >2.8 m/sec, E/A <0.8 with e' <7 cm/sec), diastolic dysfunction with elevated filling pressures is present 3

Critical Clinical Pitfalls

Do not diagnose diastolic dysfunction based solely on E/A reversal because:

• Young athletes may have E/A <1 due to enhanced atrial function (normal variant)
• Tachycardia causes E and A wave fusion, making E/A unreliable 1
• Mitral regurgitation artificially elevates E velocity, masking true diastolic function 1
• Pseudonormalization (Grade II) shows normal E/A despite worse dysfunction than Grade I 1, 4

The most dangerous error: Assuming normal E/A ratio (0.8-1.5) means normal diastolic function when it may represent pseudonormalization with elevated filling pressures. Always check E/e', LA size, and consider Valsalva maneuver in this scenario 1.

Prognostic Implications

When E/A reversal occurs with other abnormalities indicating elevated filling pressures (restrictive pattern with E/A >2, deceleration time <150 msec), it predicts poor outcomes independently of systolic function in dilated cardiomyopathy, cardiac amyloidosis, and post-MI patients 2.