An E/e′ of 5 in Atrial Fibrillation Indicates Normal Left Ventricular Filling Pressures
An average E/e′ ratio of 5 is well below the threshold for elevated left atrial pressure (LAP) and suggests normal LV filling pressures in your patient with atrial fibrillation, despite the mild hypokinesia. This finding is reassuring and does not require specific intervention for diastolic dysfunction.
Interpretation Based on Guidelines
According to the 2016 ASE/EACVI guidelines, the cutoff value for elevated LAP in patients with normal ejection fraction is average E/e′ >14 1. Your patient's E/e′ of 5 is markedly below this threshold, indicating:
- Normal left ventricular filling pressures
- No evidence of elevated LAP
- Likely Grade I diastolic dysfunction at most (if any diastolic dysfunction exists)
The guidelines specifically state that in patients with normal EF and myocardial disease, when evaluating for elevated LAP, three key parameters should be assessed 1:
- Average E/e′ ratio (cutoff >14 for elevated LAP)
- LA maximum volume index (cutoff >34 mL/m² for elevated LAP)
- TR jet velocity (cutoff >2.8 m/sec for elevated LAP)
Your patient meets none of these criteria based on the E/e′ alone, and you've confirmed normal LAVI.
Clinical Context in Atrial Fibrillation
The assessment of diastolic function in AF is more challenging than in sinus rhythm, but E/e′ remains valid and reproducible in AF patients 2. Research demonstrates that:
- In AF patients, a septal E/e′ >11 correlates with invasive LV diastolic pressures >15 mmHg 3
- E/e′ shows adequate correlation with invasive filling pressures (r = 0.47 to 0.79) in AF 2
- Elevated E/e′ (>15) is associated with impaired functional capacity, quality of life, and adverse prognosis in AF 2
Your patient's E/e′ of 5 falls far below even the lower threshold of 11, reinforcing that filling pressures are normal.
Management Approach
No specific intervention for diastolic dysfunction is needed. Your management should focus on:
1. Standard AF Management per AF-CARE Pathway 4
- [C] Comorbidity and risk factor management
- [A] Anticoagulation based on CHA₂DS₂-VASc score
- [R] Rate or rhythm control based on symptoms
- [E] Regular evaluation (6 months, then annually)
2. Address the Mild Hypokinesia
- Investigate the etiology of regional wall motion abnormality
- Consider ischemic evaluation if not already performed
- Optimize medical therapy for any underlying coronary disease
3. Rate Control Strategy (if permanent AF)
- Target resting heart rate <110 bpm (lenient control) 4
- Use beta-blocker as first-line given normal EF
- Stricter control only if symptoms persist
4. Monitor for Progression
- Repeat echocardiography if clinical status changes
- Watch for development of heart failure symptoms
- Re-assess E/e′ if symptoms of dyspnea or exercise intolerance develop
Important Caveats
Acquisition technique matters in AF: For accurate E/e′ measurement in AF patients, select cardiac cycles with 2:
- Controlled heart rate (<100 bpm)
- Similar preceding and pre-preceding RR intervals
- Cardiac cycle length and equivalence are more important than the number of beats averaged
The mild hypokinesia warrants attention: While the E/e′ is reassuring, the presence of regional wall motion abnormality with normal EF suggests either:
- Early ischemic disease
- Prior small infarction
- Tachycardia-induced changes from AF
This should be evaluated independently of the diastolic function assessment.
Normal LAVI is concordant: The combination of normal E/e′ (<14) and normal LAVI (<34 mL/m²) provides strong evidence against elevated filling pressures 1. This concordance strengthens your assessment.