Diastolic dysfunction echocardiography
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Diastolic dysfunction Microchapters |
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Diastolic dysfunction echocardiography On the Web |
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American Roentgen Ray Society Images of Diastolic dysfunction echocardiography |
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Risk calculators and risk factors for Diastolic dysfunction echocardiography |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Shankar Kumar, M.B.B.S. [2]; Rim Halaby
Overview
Diastolic dysfunction, in the presence or absence of diastolic heart failure, is a challenging diagnosis that has several diagnostic approaches. While cardiac catheterization can be used to establish the diagnosis of diastolic dysfunction by the invasive measurement of elevated left ventricular end diastolic pressure and mean pulmonary capillary pressure, echocardiography provides an alternative noninvasive diagnostic tool.
Echocardiography
There is no single echocardiographic parameter that can confirm the diagnosis of diastolic heart failure. The echocardiographic evaluation for diastolic dysfunction includes:
- Blood flow Doppler measurements of the mitral inflow velocity patterns patterns (E: early diastolic; A: late diastolic), pulmonary vein flow patterns and E:A ratio
- Tissue Doppler (TD) measurements of the left ventricular annular flow E' and E/E' ratio
- Echocardiographic calculation of the left ventricle (LV) mass index and left atrial (LA) volume index [1]
One case series found that among patients with a clinical history of heart failure and 92% with current elevated end-diastolic pressure, all had at least one echocardiographic marker of impaired diastolic function[2]:
- "LV relaxation (average, 51+/-15 ms) was abnormal in 79% of the patients"
- "E/A ratio was abnormal in 48% of the patients"
- "E-wave deceleration time (average, 349+/-140 ms) was abnormal in 64% of the patients"
The Principles of the Echocardiographic Evaluation
The diagnosis of diastolic dysfunction relies on the evaluation of the status of the left ventricular function and on the presence of any variations in the ventricular filling pressures.
In order to know what to expect as findings in the evaluation of diastolic dysfunction, it is important to understand the physiological role of the left atrium (LA) during diastole and how it contributes to the ventricular filling.
- The LA functions as a reservoir that receives the venous blood when the mitral valve is closed
- The LA functions as a conduit of blood from the atrium to the ventricle when the mitral valve is open
- The LA functions as a pump of the remaining blood in the LA into the LV at the end of diastole while preserving a normal LVEDP
Hence, in diastolic dysfunction, the increased stiffness and diastolic dysfunction of the left ventricle impair the "conduit" role of the LA and cause a decrease in early diastolic atrio-ventricular gradient. As a consequence, the "reservoir" and "pump" role of the LA will try to compensate to maintain a normal stroke volume and left ventricular end diastolic volume at the expense of an elevated LVEDP.[3]
The predictors of the filling pressure and the degree of myocardial disease progression are essentially the mean pulmonary wedge pressure (PCWP, which is equal to the mean left atrial pressure in the absence of mitral stenosis) and the left ventricular end diastolic pressure (LVEDP).
- The diastolic phase of the cardiac cycle is normally characterized by rapid blood filling at low left ventricular pressures
- The hallmark of diastolic dysfunction is elevated left ventricular end diastolic pressure or filling pressure
- The cut off values used for the diagnosis of diastolic dysfunction are:
- PCWP >12 mmHg
- LVEDP> 16mmHg [4]
- The PCWP and LVEDP are obtained by invasive measurements done by cardiac catheterization.
The importance of echocardiography is that it provides a non invasive way to assess the heart for diastolic dysfunction through the evaluation of several parameters:
LV Wall Thickness
- The evaluation of the left ventricle is important because cardiac hypertrophy, usually secondary to hypertension, is a well known cause of diastolic dysfunction.
Left Atrial Volume
- The assessment of the left atrium volume helps in the detection of any left atrial remodeling secondary to diastolic dysfunction.[5]
Pulmonary Artery Systolic and Diastolic Pressure
- Increase in pulmonary artery pressure, in the absence of any pulmonary disease, is indicative of diastolic dysfunction.[6]
Left Ventricular Filling
- The assessment of the left ventricular filling can be derived from the evaluation of:
- The mitral inflow velocities by Doppler ultrasound.
- Peak E: early diastolic mitral inflow velocity
- Peak A: late diastolic mitral inflow velocity
- E/A ratio
- DT: Deceleration time of early filling velocities
- IVRT: Isovolumetric relaxation time
- Middiastolic flow
- The pulmonary vein flow velocity
- Peak S (systolic) and D (anterograde diastolic) velocities
- S/D ratio
- Systolic filling fraction (S time-velocity intergral/S time-velocity integral + D time-velocity integral)
- Peak Ar velocity in late diastole
- The time difference between Ar duration and mitral A-wave duration (Ar-A).
- Left ventricular annular flow (e') and E/e' ratio[3]
- The mitral inflow velocities by Doppler ultrasound.
Findings on Echocardiography in Diastolic dysfunction[3]
- The diagnosis of diastolic dysfunction requires the estimation of the left ventricular filling pressures from the calculation of the E/e' ratio:
- E/e' less than or equal to 8: Normal LV filling pressure
- E/e' more than or equal to 13: Increase LV pressure
- E/e' between 9 and 12: Other measurements are needed to estimate the LV filling pressure.
- The presence of two or more of the following abnormal measurements increase the confidence in the diagnosis of diastolic dysfunction:
- Ar-2-A duration >30 ms
- Change in E/A ratio with the Valsalva maneuver of >0.5
- PA systolic pressure >35 mm Hg (in the absence of pulmonary disease)
- Maximal LA volume >34 mL/m2
- Short mitral DT (<140 ms)
Assessment of LV Filling Pressures in Special Populations[3]
| Disease | Echocardiographic measurements and cutoff values |
| Atrial fibrillation | Peak acceleration rate of mitral E velocity (≥1,900 cm/s2), IVRT (≤65 ms), DT of pulmonary venous diastolic velocity (≤220 ms), E/Vp ratio (≥1.4), and septal E/e= ratio (≥11). |
| Sinus tachycardia | Mitral inflow pattern with predominant early LV filling in patients with EFs <50%, IVRT ≤70 ms is specific (79%), systolic filling fraction ≤40% is specific (88%), lateral E/é >10 (a ratio >12 has highest the specificity of 96%) |
| Hypertrophic cardiomyopathy | Lateral E/é (≥10), Ar - A (≥30 ms), PA pressure (>35 mm Hg), and LA volume (≥34 mL/m2) |
| Restrictive cardiomyopathy | DT (<140 ms), mitral E/A (>2.5), IVRT (<50 ms has high specificity), and septal E/é (>15) |
| Non cardiac pulmonary hypertension | Lateral E/é can be applied to determine whether a cardiac etiology is the underlying reason for the increased PA pressures (cardiac etiology: E/é >10; noncardiac etiology: E/é <8) |
| Mitral stenosis | IVRT (<60 ms has high specificity), IVRT/ TE - e= (<4.2), mitral A velocity (>1.5 m/s) |
| Mitral regurgitation | Ar - A (>30 ms), IVRT (<60 ms has high specificity), and IVRT/TE - e= (<3) may be applied for the prediction of LV filling pressures in patients with MR and normal EFs, whereas average E/é (><15) is applicable only in the presence of a depressed EF. |
Diastolic Stress Test
- Diastolic dysfunction is characterized by an increase in the left ventricular filling pressures. During exercise, the stroke volume and left ventricular filling volumes are increased at the expense of further increase in the filling pressures. The evaluation of the LV function during diastolic stress test has the same concept of cardiac stress test.
- Interpretation of the E/e' ratio in diastolic stress test:
- Normal diastolic function:
- E and e' increase proportionally
- E/e' ratios at rest and after exercise are the same
- Impaired myocardial relaxation:
- The increase in e' is significantly inferior to that of E
- E/e' ratio is elevated [7]
- Normal diastolic function:
Approach to Grade Diastolic Dysfunction
Shown below is a flowchart which provides a scheme for grading diastolic dysfunction. (Av., average; LA., left atrium; Val., Valsalva)
Estimation of Filling Pressure in Patients with Normal Ejection Fraction
Shown below is a flowchart which provides an algorithm for estimation of LV filling pressures in patients with normal EFs (Av, average).
References
- ↑ Walter J.How to diagnose diastolic heart failure: a consensus statement on the diagnosis of heart failure with normal left ventricular ejection fraction by the Heart Failure and Echocardiography Associations of the European Society of Cardiology.Eur Heart J(2007)28(20): 2539-2550.doi:10.1093/eurheartj/ehm037
- ↑ Zile MR, Gaasch WH, Carroll JD, Feldman MD, Aurigemma GP, Schaer GL; et al. (2001). "Heart failure with a normal ejection fraction: is measurement of function necessary to make the diagnosis of heart failure?". Circulation. 104 (7): 779–82. PMID 11502702.
- ↑ 3.0 3.1 3.2 3.3 Nagueh SF, Appleton CP, Gillebert TC, Marino PN, Oh JK, Smiseth OA; et al. (2009). "Recommendations for the evaluation of left ventricular diastolic function by echocardiography". J Am Soc Echocardiogr. 22 (2): 107–33. doi:10.1016/j.echo.2008.11.023. PMID 19187853.
- ↑ Paulus WJ, Tschope C, Sanderson JE, Rusconi C, Flachskampf FA, Rademakers FE, et al. How to diagnose diastolic heart failure: a consensus statement on the diagnosis of heart failure with normal left ventricular ejection fraction by the Heart Failure and Echocardiography Associations of the European Society of Cardiology. Eur Heart J 2007;28: 2539-50.
- ↑ Tsang TS, Barnes ME, Gersh BJ, Bailey KR, Seward JB. Left atrial volume as a morphophysiologic expression of left ventricular diastolic dysfunction and relation to cardiovascular risk burden. Am J Cardiol 2002;90: 1284-9
- ↑ Bouchard JL, Aurigemma GP, Hill JC, Ennis CA, Tighe DA. Usefulness of the pulmonary arterial systolic pressure to predict pulmonary arterial wedge pressure in patients with normal left ventricular systolic function. Am J Cardiol 2008;101:1673-6.
- ↑ Ha JW, Oh JK, Pellikka PA, Ommen SR, Stussy VL, Bailey KR, et al. Diastolic stress echocardiography: a novel noninvasive diagnostic test for diastolic dysfunction using supine bicycle exercise Doppler echocar- diography. J Am Soc Echocardiogr 2005;18:63-8.