LV Diastolic Function
Definition
LV diastolic function encompasses LV relaxation (the active, energy-dependent process of LV pressure decline after systole) and LV chamber stiffness (the passive property resisting filling). Diastolic dysfunction is defined echocardiographically by a combination of reduced e' velocity (impaired relaxation) and markers of elevated LV filling pressures and structural remodeling. (sources/echo-hfpef-ase-2025, rating: very high)
Key Concepts
Mechanistic Basis — Relaxation, Recoil and Stiffness (Nagueh 2020)
- Diastolic function has three determinants — myocardial relaxation, early diastolic recoil and chamber stiffness — which together set LV filling pressure. Echocardiographic surrogates map onto each: e′, SR_IVR and SR_E for relaxation; LV untwisting rate for recoil; deceleration time and A-wave transit time for chamber stiffness (sources/lvdiastolic-echo-jaccimaging-2020, rating: high)
- Cellular relaxation depends on calcium uptake by SERCA2a (regulated by phospholamban); SERCA2a expression is reduced in heart failure, slowing relaxation. Titin isoforms determine passive tension and recoil — N2BA/N2B is increased in HFrEF (more compliant, reduced restoring forces), whereas N2B predominates in HFpEF (stiffer, preserved recoil) (sources/lvdiastolic-echo-jaccimaging-2020, rating: high)
- e′ is the most feasible, reproducible and prognostically validated relaxation index. Its preload dependence differs by relaxation state: with normal relaxation the transmitral gradient affects e′, whereas with impaired relaxation LA pressure has little effect because e′ is delayed until LV diastolic pressure equals or exceeds LA pressure. This is why E/e′ estimates filling pressure in myocardial disease but not in normal hearts (sources/lvdiastolic-echo-jaccimaging-2020, rating: high)
- E/e′ thresholds: average <8 = normal LVFP; >14 = elevated LVFP. E/e′ should not be used in constrictive pericarditis (annulus reversus), moderate/severe MAC, mitral stenosis, severe primary MR with normal EF, prosthetic mitral valve, or when septal e′ is reduced by LBBB/pacing — in the latter, combine with LA volume and PASP (sources/lvdiastolic-echo-jaccimaging-2020, rating: high)
- E/SR_IVR relates directly to mean wedge pressure and was more accurate than E/e′ in segmental dysfunction and normal EF — an alternative when e′ is unreliable, though limited by image quality and lack of standardisation (sources/lvdiastolic-echo-jaccimaging-2020, rating: high)
- LA reservoir strain correlates inversely with wedge pressure and LVEDP irrespective of EF and tracks diastolic grade; LA stiffness (E/e′ ÷ LA strain) is increased in HFpEF and relates to pulmonary artery pressure and vascular resistance. LA strain is confounded by reduced LV systolic function and is not validated in AF, MAC or mitral valve disease (sources/lvdiastolic-echo-jaccimaging-2020, rating: high)
Invasive Hemodynamic Reference Standards
- LV relaxation time constant τ >48 ms = impaired relaxation (load-dependent) (sources/echo-hfpef-ase-2025, rating: very high)
- LV chamber stiffness constant >0.015 = increased stiffness (sources/echo-hfpef-ase-2025, rating: very high)
- Invasive HFpEF thresholds: rest mean PCWP >15 mmHg, rest LVEDP >16 mmHg, exercise mean PCWP ≥25 mmHg, exercise LVEDP ≥23 mmHg (sources/echo-hfpef-ase-2025, rating: very high)
- LVEDP ≠ mean LAP: Elevated LVEDP can occur with normal LAP (early-stage diastolic dysfunction). Doppler correlates of LVEDP include mitral A velocity, pulmonary vein Ar velocity, Ar-A duration, and LA pump strain. Correlates of mean LAP include mitral E velocity, E/A ratio, E/e' ratio, and LARS. (sources/echo-hfpef-ase-2025, rating: very high)
Key Echocardiographic Parameters
- Mitral annular e' velocity: Best index of LV relaxation; reduced across all grades of dysfunction; less load-dependent than E velocity; lateral, septal, and average have different cutoffs; unreliable with significant MAC, prosthetic MV, pericardial disease, and regional dysfunction at sampled site (sources/echo-hfpef-ase-2025, rating: very high)
- E/e' ratio: Average >14 = high specificity for elevated LAP; average <8 = normal; 8–14 = grey zone/indeterminate; septal ≥15 or lateral ≥13 also abnormal thresholds (sources/echo-hfpef-ase-2025, rating: very high)
- LA Reservoir Strain (LARS): Peak positive LA strain during ventricular systole; ≤18% = high specificity for elevated LAP; correlates inversely with LAP; LA stiffness index = E/e' ÷ LARS (highest accuracy for HFpEF identification); LARS should NOT be used to assess LAP in AF, significant MR, HTX, normal EF with GLS >18%, or suspected LA stunning; age-dependent (decreases with age) (sources/echo-hfpef-ase-2025, rating: very high)
- LAVi: Marker of chronic (not acute) LAP elevation; >34 mL/m² abnormal; poor correlation with acute LAP changes; secondary marker in current algorithm (not primary); non-diastolic causes: anemia, athletic heart, AF/flutter, MV disease, high-output states (sources/echo-hfpef-ase-2025, rating: very high)
- TR velocity / PASP: Elevated PASP passively reflects elevated LAP in absence of pulmonary vascular disease; PASP ≥35 mmHg (or TR velocity ≥2.8 m/s when RAP unavailable) = elevated LAP; use intravenous agitated saline or UEA to complete incomplete TR envelopes (sources/echo-hfpef-ase-2025, rating: very high)
- PV S/D ratio: ≤0.67 (= systolic filling fraction ≤40%) indicates elevated mean LAP; most reliable with reduced LVEF; unreliable in normal EF, AF, HCM, MV disease (sources/echo-hfpef-ase-2025, rating: very high)
- IVRT: ≤70 ms = elevated LAP (high specificity); >110 ms = likely normal LAP; age-dependent and preload-dependent; particularly useful in MAC (sources/echo-hfpef-ase-2025, rating: very high)
- Ar-A duration: >30 ms = elevated LVEDP; age- and EF-independent; accurate in MR and HCM (sources/echo-hfpef-ase-2025, rating: very high)
- Valsalva maneuver: E/A decrease ≥50% = highly specific for elevated LAP; age-independent; standardize as 40 mmHg intrathoracic pressure sustained for 10 s (sources/echo-hfpef-ase-2025, rating: very high)
Age-Specific Normal Ranges
- E wave, A wave, E/A ratio, e' velocity, E/e' ratio, TR velocity, LAVi, and LARS are all significantly age-dependent
- Age-specific cutoffs for impaired LV relaxation (e' velocity):
| Age Group | Septal e' (cm/s) | Lateral e' (cm/s) | Average e' (cm/s) |
|---|---|---|---|
| 20–39 y | <7 | <10 | <9 |
| 40–65 y | <6 | <8 | <7 |
| >65 y | <6 | <7 | <6.5 |
- Normal ranges ≠ optimal values — aging itself reduces diastolic function
- E/e' ratio and LAVi show near-linear (no threshold) associations with HF incidence/death in older adults (sources/echo-hfpef-ase-2025, rating: very high)
Two-Step Algorithm for Diagnosing Diastolic Dysfunction
Step 1: Assess e' as marker of impaired LV relaxation
- Reduced e': septal ≤6 cm/s OR lateral ≤7 cm/s OR average ≤6.5 cm/s (age-adjusted cutoffs can also be used)
Step 2: Assess markers of LA/LV remodeling and elevated LAP:
- Average E/e' >14
- LARS ≤18%
- E/A ≤0.8 (age-adjusted) OR ≥2
- LAVi >34 mL/m² (excluding athletes, anemia, AF, flutter, MV disease)
Diastolic dysfunction present if:
- Reduced e' + ≥1 marker from Step 2, OR
- Normal e' + ≥2 markers from Step 2
Additional finding: LV mass index >115 g/m² (men) or >95 g/m² (women) after excluding athletes (sources/echo-hfpef-ase-2025, rating: very high)
LAP Estimation Algorithm (Sinus Rhythm)
Three primary variables (apply to all sinus rhythm patients except: severe primary MR, any MS, moderate/severe MAC, AF, HTX, non-cardiac PH, pericardial constriction, LVAD):
- Reduced e' (septal ≤6 or lateral ≤7 or average ≤6.5 cm/s)
- Elevated E/e' (septal ≥15, lateral ≥13, or average ≥14)
- Elevated TR velocity ≥2.8 m/s (when RAP unknown) or PASP ≥35 mmHg
Algorithm outcomes:
- All 3 normal → Normal LAP → Normal diastolic function
- All 3 abnormal OR any 2 abnormal → Elevated LAP; Grade 2 if E/A <2; Grade 3 if E/A ≥2
- Only e' reduced + E/A ≤0.8 → Grade 1 diastolic dysfunction (impaired relaxation, normal LAP)
- Any 1 or 2 abnormal with E/A >0.8 → Assess supplemental: LARS ≤18%, PV S/D ≤0.67, LAVi >34 mL/m², IVRT ≤70 ms
- If ≥1 supplemental positive → Elevated LAP
- If all supplemental normal → Normal LAP (consider exercise echo if symptomatic)
Key change from 2016 guidelines: LAVi no longer a primary variable (demoted to supplemental due to poor tracking of acute LAP changes and non-diastolic causes of enlargement) (sources/echo-hfpef-ase-2025, rating: very high)
Grading Diastolic Dysfunction
- Grade 1 (Mild): Reduced e', normal E/e' + PASP, E/A ≤0.8 — impaired LV relaxation with normal LAP
- Grade 2 (Mild to Moderate): Elevated LAP, E/A >0.8 but <2
- Grade 3 (Severe/Marked): Elevated LAP, E/A ≥2 (restrictive filling)
Diastolic Exercise Echocardiography
- Indications: Symptomatic patients with Grade 1 diastolic dysfunction or indeterminate resting LAP; up to 50% of HFpEF patients have normal resting LAP
- Not indicated if: Normal diastolic function at rest with preserved e' (unlikely to develop elevated pressures), or already elevated resting filling pressures (diagnosis established)
- Performance: Supine bicycle preferred; treadmill acceptable; dobutamine stress strongly discouraged
- Positive (definite): Average E/e' ≥14 (or septal ≥15) AND peak TR velocity >3.2 m/s during exercise
- Normal: Average E/e' <10 AND TR velocity <2.8 m/s during exercise
- Likely HFpEF: E/e' >14 + TR velocity >2.8 but <3.2 m/s
- PASP >50 mmHg portends worse prognosis
- 17% of patients develop elevated filling pressures with exercise; elevated filling pressure without ischemia has worse prognosis than isolated ischemia (sources/echo-hfpef-ase-2025, rating: very high)
Special Population Modifications
Atrial Fibrillation
- No single parameter has strong enough association to stand alone
- Algorithm (Figure 8): 4 primary variables (E velocity ≥100 cm/s, septal E/e' >11, TR >2.8 m/s or PASP >35 mmHg, DT ≤160 ms)
- 0–1 abnormal: normal LAP (unless LARS <18%, PV S/D <1, or BMI >30)
- 2 abnormal: indeterminate; ≥3 abnormal: elevated LAP
- Less beat-to-beat transmitral inflow variability with varying cycle length = elevated LAP (sources/echo-hfpef-ase-2025, rating: very high)
Mitral Regurgitation
- Primary MR with normal EF: E/e' ratio not reliable; use Ar-A duration >30 ms and IVRT/TE-e' <5.6
- MR with depressed EF: E/e' >14 has direct relation to LAP and predicts hospitalizations/mortality
- LARS has no significant relationship with LAP in significant MR (sources/echo-hfpef-ase-2025, rating: very high)
MAC (Moderate/Severe)
- E/A <0.8 → normal LAP; E/A >1.8 → elevated LAP
- E/A 0.8–1.8 → measure IVRT: ≥80 ms = normal, <80 ms = elevated (sources/echo-hfpef-ase-2025, rating: very high)
Pulmonary Hypertension
- Septal flattening → lateral E/e' preferred (not average); lateral E/e' >13 = elevated LAP; <8 = normal; 8–13 = indeterminate
- E/A ≤0.8 favours precapillary PH; E/A ≥2 favours postcapillary (Group II) PH
- Combine with LAVi >34 mL/m² and LARS <16% to identify Group II PH (sources/echo-hfpef-ase-2025, rating: very high)
Cardiac Transplantation
- Avg E/e' <7 = normal LAP; >14 = elevated LAP; 7–14 → SRIVR (E/SRIVR ratio ≤200 cm = normal; >200 cm = elevated); if SRIVR unavailable → TR velocity (≤2.8 m/s normal; >2.8 m/s elevated) (sources/echo-hfpef-ase-2025, rating: very high)
LBBB / RV Pacing / CRT
- Septal e' reduced by dyssynchrony → lateral E/e' preferred; average and septal E/e' less reliable
- If E+A fusion (complete): rely on TR velocity and LAVi/LARS for filling pressure estimation (sources/echo-hfpef-ase-2025, rating: very high)
Restrictive Cardiomyopathy / Cardiac Amyloidosis
- Advanced disease: E/A >2.5, DT <150 ms, IVRT <50 ms, e' 3–4 cm/s; Grade 3 = poor prognosis
- Cardiac amyloidosis "5-5-5 sign": systolic/e'/a' annular velocities all <5 cm/s
- Amyloidosis apical sparing: apical/mid+basal strain ratio >1; septal apical-to-basal ratio >2.1; EF/strain ratio >4.1 — differentiates from HCM, hypertensive LVH, AS (sources/echo-hfpef-ase-2025, rating: very high)
Pericardial Constriction
- Key features distinguishing from restrictive CM:
- Respirophasic septal shift (>25% mitral / >40% tricuspid inflow variation)
- Normal or elevated medial annular e' (>7 cm/s) — annulus reversus
- Expiratory hepatic vein reversal/forward ≥0.8
- Lateral and RV free wall strain diminished vs septum — strain reversus
- TE-e' interval typically NOT prolonged (prolonged in restrictive CM) (sources/echo-hfpef-ase-2025, rating: very high)
AI Applications
- Multiple approaches: rule-based, multi-view ML, single-view deep learning (from apical 4-chamber)
- Continuous diastolic function score (reduces "indeterminate" labelling)
- Electrocardiographic AI models showed good accuracy for diastolic dysfunction grades with similar prognostic value to echo (n~100,000 paired ECG/echo)
- All current AI models trained on 2016 guidelines — validation against invasive hemodynamics and outcomes needed (sources/echo-hfpef-ase-2025, rating: very high)
Diastolic Dysfunction and Arrhythmic Death Risk
- Grade III diastolic dysfunction (restrictive pattern) is independently associated with a 3.52-fold increased risk for arrhythmic death (AD) or resuscitated cardiac arrest (RCA) in ischaemic and dilated cardiomyopathy (HR 3.52; 95% CI 2.00–6.22; P<0.001), adjusted for ICD implantation, QRS duration, hypertension, and diuretics. (sources/arrhythmia-diastolic-circep-2020, rating: medium)
- This association is independent of LVEF: persists in both LVEF ≤35% (P=0.001) and LVEF >35% (P=0.014) subgroups — suggesting diastolic grading adds incremental arrhythmic risk information beyond the standard ICD threshold. (sources/arrhythmia-diastolic-circep-2020, rating: medium)
- 8-year cumulative AD/RCA risk by diastolic grade: 58% (grade III) vs 37% (grade II) vs 22% (grade I) vs 5% (normal). No patient with normal diastolic function died of arrhythmic death. (sources/arrhythmia-diastolic-circep-2020, rating: medium)
- Grade I dysfunction was protective for arrhythmic events (HR 0.41; 95% CI 0.23–0.71; P=0.002); grade II was neutral (HR 1.03; P=0.93). (sources/arrhythmia-diastolic-circep-2020, rating: medium)
- In the LVEF >35% subgroup, grade III patients had 41% cumulative AD/RCA risk at 8 years — comparable to patients meeting LVEF ≤35% ICD criteria — suggesting a high-risk group currently missed by standard thresholds. (sources/arrhythmia-diastolic-circep-2020, rating: medium)
- Proposed mechanism: grade III dysfunction reflects advanced myocardial fibrosis and ventricular stiffness, which create anatomical reentry substrate for ventricular tachyarrhythmia.
- Note: pilot study (n=210, single centre); diastolic grading used pre-2016 ASE criteria. Not yet incorporated into ICD guidelines. See concepts/VA-Risk-Stratification-DCM and entities/ICD for the broader arrhythmic risk framework.
Contradictions / Open Questions
- LAVi as a primary vs supplemental variable: The 2016 ASE guidelines included LAVi as a primary parameter. The 2025 update demoted it to secondary/supplemental due to its weak and indirect correlation with acute LAP changes and multiple non-diastolic causes of LA enlargement. However, LAVi retains prognostic value (independent predictor of death, HF, AF, stroke) creating a tension between its prognostic and diagnostic roles. (sources/echo-hfpef-ase-2025, rating: very high)
- LARS age-dependence and EF-dependence: LARS has highest LAP estimation accuracy in patients with reduced LVEF; in normal EF patients it can be normal despite elevated LAP (especially if GLS >18%). This means LARS is most useful precisely in the patients where clinical diagnosis of HFpEF is already clearest, and least useful in the more ambiguous preserved EF group. (sources/echo-hfpef-ase-2025, rating: very high)
- E/e' grey zone (8–14) remains unresolved: Despite replacing the 2016 4-variable algorithm, a substantial grey zone persists for E/e' ratio between 8–14 where LAP is indeterminate. The 2025 update adds LARS and supplemental parameters to resolve this but accuracy in the grey zone remains moderate. (sources/echo-hfpef-ase-2025, rating: very high)
- Age-specific prognostic thresholds only validated for >65 years: The ARIC study data providing prognostically relevant diastolic measurements covers only adults >65 years. For younger patients, the 2025 guidelines use normal range cutoffs rather than outcomes-based thresholds, creating potential misclassification in younger individuals. (sources/echo-hfpef-ase-2025, rating: very high)
- E/e′ — defended in 2020, constrained in 2025. The 2020 review argues that studies reporting poor E/e′ accuracy in HFpEF are small and methodologically flawed, and that E/e′ remains useful in myocardial disease. The 2025 ASE guideline retains E/e′ as a primary variable but adds LA reservoir strain and demotes LAVi, reflecting an updated evidence appraisal. The disagreement is not about physics but about how much weight to place on imperfect correlation in heterogeneous populations (sources/lvdiastolic-echo-jaccimaging-2020, rating: high; sources/echo-hfpef-ase-2025, rating: very high)
- 2016 versus 2025 algorithm — the four-parameter rule is now historical. The 2020 review describes the 2016 ASE/EACVI approach using e′, average E/e′, TR velocity and LAVi with a majority rule. The 2025 update replaces this with a stepwise algorithm based on reduced e′ plus LAP markers, and demotes LAVi to a supplemental variable because it tracks chronic rather than acute pressure and has many non-diastolic causes. Clinicians following the older algorithm may label patients differently (sources/lvdiastolic-echo-jaccimaging-2020, rating: high; sources/echo-hfpef-ase-2025, rating: very high)
- Diastolic grade III as an arrhythmic risk marker vs. current LVEF-centric ICD guidelines: Pezawas et al. (2020, n=210, 7-year follow-up) found grade III diastolic dysfunction independently predicted arrhythmic death regardless of LVEF (HR 3.52), with the LVEF >35% subgroup facing 41% cumulative AD/RCA risk at 8 years — comparable to ICD-eligible LVEF ≤35% patients. Current ICD guidelines do not incorporate diastolic grading. Whether grade III dysfunction should complement LVEF thresholds for primary prevention ICD decisions requires large prospective validation. (sources/arrhythmia-diastolic-circep-2020, rating: medium)
Connections
- Related to entities/HFpEF
- Related to entities/Heart-Failure
- Related to entities/HCM
- Related to entities/ATTR-Amyloidosis
- Related to entities/Atrial-Fibrillation
- Related to concepts/Pulmonary-Hypertension
- Related to concepts/Valvular-Heart-Disease
- Related to concepts/VA-Risk-Stratification-DCM — diastolic grade III as LVEF-independent arrhythmic risk predictor
- Related to entities/ICD — diastolic grading as candidate additional primary prevention criterion
- Related to sources/echo-hfpef-ase-2025
- Related to sources/arrhythmia-diastolic-circep-2020