Diastolic Function

Diastolic assessment should answer two questions:

Is LV diastolic dysfunction present?
Is left atrial pressure (LAP) elevated?

Interpret all measurements together. Rhythm, heart rate, blood pressure, loading conditions, mitral valve disease, and technical quality may alter the findings.

Routine Measurements¶

Parameter	Abnormal value
Septal e′	≤6 cm/s
Lateral e′	≤7 cm/s
Average e′	≤6.5 cm/s
Average E/e′	>14
Septal E/e′	≥15
Lateral E/e′	≥13
Peak TR velocity	≥2.8 m/s
PASP	≥35 mm Hg
LAVI	>34 mL/m²
LA reservoir strain	≤18%

Age-specific e′ thresholds may be used:

Age	Septal e′	Lateral e′	Average e′
20–39 years	<7 cm/s	<10 cm/s	<9 cm/s
40–65 years	<6 cm/s	<8 cm/s	<7 cm/s
>65 years	<6 cm/s	<7 cm/s	<6.5 cm/s

Diagnosis of Diastolic Dysfunction¶

First assess mitral annular e′ as the primary marker of impaired relaxation.

Then assess:

Average E/e′ >14
LA reservoir strain ≤18%
Mitral E/A ≤0.8 or ≥2
LAVI >34 mL/m²

Diastolic dysfunction is present when:

e′ is reduced and at least one additional marker is abnormal, or
e′ is preserved but at least two additional markers are abnormal

Increased LV mass also supports diastolic dysfunction:

Women: LV mass index >95 g/m²
Men: LV mass index >115 g/m²

Exclude physiologic remodeling in athletes before using chamber enlargement or increased LV mass as evidence of diastolic dysfunction.

LAP and Diastolic Grade¶

For most patients in sinus rhythm, begin with:

Mitral annular e′
E/e′
TR velocity or PASP

Grade	Typical findings	LAP
Normal	All three primary variables normal	Normal
Grade I	Reduced e′, normal E/e′ and PASP, E/A ≤0.8	Normal
Grade II	Findings support elevated LAP; E/A <2	Mild-to-moderately elevated
Grade III	Findings support elevated LAP; E/A ≥2	Markedly elevated

When only one or two primary variables are abnormal, use additional evidence:

Pulmonary vein S/D ratio ≤0.67
LA reservoir strain ≤18%
LAVI >34 mL/m²
IVRT ≤70 ms

Other supportive findings include:

Pulmonary vein Ar duration exceeding mitral A duration by >30 ms
Mitral L-wave velocity ≥50 cm/s
PR end-diastolic velocity ≥2 m/s
PA diastolic pressure ≥16 mm Hg
≥50% decrease in E/A with Valsalva

LAVI reflects chronic exposure to elevated filling pressure and may remain enlarged after LAP normalizes. It may also be increased with atrial arrhythmias, anemia, mitral valve disease, high-output states, or athletic remodeling.

Important Limitations¶

Do not apply the general algorithm without modification in:

Atrial fibrillation
Moderate or severe mitral annular calcification
Mitral stenosis
Severe primary mitral regurgitation
Mitral valve repair or replacement
Mitral transcatheter edge-to-edge repair
Heart transplantation
LV assist devices
Noncardiac pulmonary hypertension
Pericardial constriction

E and A waves may fuse during tachycardia or prolonged PR intervals. Average several representative beats when rhythm or loading conditions vary.

Normal resting LAP does not exclude HFpEF. Consider diastolic exercise echocardiography when symptoms remain suspicious despite normal resting measurements.

Suggested Reporting¶

Left ventricular diastolic function is normal.

Grade I left ventricular diastolic dysfunction is present with normal estimated left atrial pressure.

Grade II left ventricular diastolic dysfunction is present with elevated estimated left atrial pressure.

Grade III left ventricular diastolic dysfunction is present with markedly elevated estimated left atrial pressure.

Diastolic function is indeterminate because of discordant parameters.

Diastolic function cannot be reliably assessed because of [atrial fibrillation/mitral valve disease/tachycardia].

Key Points¶

Reduced e′ indicates impaired myocardial relaxation.
E/e′ estimates filling pressure but should not be used alone.
LAVI reflects chronic rather than instantaneous loading conditions.
E/A ≥2 with supporting evidence indicates restrictive filling and elevated LAP.
Diastolic grade and estimated LAP should both appear in the report when feasible.