Assessment of left ventricular function The InGenious HyperCare European Network Excellence in phenotyping: Assessment of left ventricular function Tatiana Kuznetsova University of Leuven, Belgium

LVF Outline Systolic function Diastolic function Echocardiographic protocol (JRP A3)

LVF Systolic function Conventional echocardiography enables the assessment of LV dimensions, volumes, sphericity index, and severity of mitral regurgitation; HF due to systolic dysfunction is relatively easy to diagnose by echocardiography. (dilated left ventricle with a reduced ejection fraction)

LVF Components of regional function Radial function Longitudinal Circumferential Without the longitudinal component, sarcomere shortening would lead to an EF < 30%.

LVF Tissue Doppler imaging Tissue Doppler Imaging (TDI) makes it possible to specifically evaluate the longitudinal and radial components of regional LV systolic function. Measurements of myocardial deformation with the Doppler technique have been validated using microcrystals and MRI (Urheim S, Circulation 2000; Edvardsen T, Circulation 2002).

Basal segments of inferior and infero-lateral walls LVF Off-line analysis Strain rate Strain AVC MVO Time integration AVC MVO Basal segments of inferior and infero-lateral walls Peak systolic SR End-systolic S SPEQLE: Software Package for Echocardiographic Quantification, Leuven; version 4.06

LVF Inter-observer differences in percent versus average of two readings Mean of 2 readings Bland and Altman, 1986

LVF Longitudinal S and SR by RWT Mean values are adjusted; * P 0.05 ***P0.001

LVF Regional LV geometry Wall stress related to: σ = P x R / 2WT Pressure ↑ → σ ↑ Shape, cavity size ↑ → σ ↑ Wall thickness ↑ → σ ↓ σ = P x R / 2WT Since R curvature is larger in longitudinal direction, the stress on longitudinal fibres is higher, they show decreased deformation first.

LVF Systolic function TDI, compared with conventional echocardiography, is a more sensitive method for the detection of LV systolic dysfunction, particularly in subjects with LV remodelling and normal EF. Our observations underscore the importance of normal long axis function in maintaining a coordinated ventricular contraction. The clinical utility of strain and strain rate in risk stratification or as therapeutic target remains to be established.

LVF Diastolic function About 50% of patients with new onset of HF do have a normal EF (HF with preserved EF). HF with preserved EF is associated with a high mortality rate, comparable to that of patients with reduced EF. (Bhatia R.S., N Engl J Med 2006; Bursi F., JAMA 2006) Assessment of diastolic function requires conventional and Tissue Doppler Imaging

LVF Transmitral blood flow vs pulsed Tissue Doppler Imaging A E Ea Aa

LVF Inter-observer differences in percent versus average of two readings Mean of 2 readings Bland and Altman, 1986

LVF Determinants of TDI velocities Stepwise analysis: Ea: age, BMI, DBP, LVMI; LV length, EF; Aa: age, HR, DBP, LV length, EF; Ea/Aa: age, BMI, HR, DBP. Intrafamilial correlation coefficients (P<0.0001 for all) were: Ea: 0.43; Aa: 0.41; Ea/Aa: 0.46.

Echo Echocardiographic performance protocol A single observer performs all echocardiographic examinations by means of Vivid 7 ultrasound scanner (GE Vingmed, Horten, Norway) Standardized echocardiography scanning sequence (about 40 min, page 76-77 MOP JRP A3) Correct orientation of the ultrasound beam and imaging planes to LV structure and blood flow is essential All echocardiographic examinations in a digital format are stored on a local network for off-line reading by two independent observers (EchoPack, GE and SPEQLE, University of Leuven)

Echo Methods to limit echocardiographic measurement variability Use echocardiography central reading laboratory: a. Minimize number of readers, b. Monitor reader variability, c. Rapid communication with study sites on study quality. Standardized “hands-on” training of sonographers onsite. Monitoring of sonographers for technical quality; encode study quality in database. American Society of Echocardiography Recommendations for Use of Echocardiography in Clinical Trials. J Am Soc Echocardiogr 2004;17:1086-1119

Echo Methods to limit echocardiographic measurement variability Reading off-line strategies: Batch read when possible to minimize systematic temporal drifts; Average multiple beats (minimum of 3); Single reader preferable. Establish acquisition and reader variability: Test-retest of small sample of participants, ie, same participant repeated over small interval, same machine, same sonographer, same reader; Blind duplicates for inter-reader and intra-reader variability assessment.

JRP A3 Echo-centers Katholieke Universiteit Leuven, B JA Staessen, T Kuznetsova, T Richart Jagiellonian University Cracow, PL K Kawecka-Jaszcz, K Stolarz, M Loster Medical University of Gdansk, PL K Narkiewicz, W Sakiewicz, A Rojek Universitá degli Studi di Padova, I E Casiglia, V Tikhonoff Hospital Universitari Valencia, SP E Lurbe, J Alvarez Institute of Internal Medicine, RU Y Nikitin, S Malyutina, A Ryabikov