P4372Left atrial strain: a potential marker of early diastolic dysfunction in patients with Marfan syndrome

Background/Introduction

Previous studies using conventional echocardiographic measurements have reported subclinical left diastolic dysfunction in patients with Marfan syndrome (MFS). Left atrial strain (LAS) has been shown to be an accurate predictor of left ventricular diastolic dysfunction. However, there is no evidence regarding the use of LAS in MFS.

Purpose

To assess feasibility of LAS and compare LAS derived measurements along with traditional diastolic parameters in MFS patients vs healthy controls.

Methods

46 MFS patients (normal LV ejection fraction, no previous cardiovascular surgery, no significant valvular regurgitation) vs. 20 healthy controls (age and sex-matched). We performed LAS analysis using 2D speckle-tracking (QLAB 10, Philips). LA strain was determined as the average value of the longitudinal deformation (7 segments) in the apical 4-chamber view (RR gating).

Results

LAS analysis was feasible in 40 MFS patients (87%). All participants had normal diastolic function according to current guidelines (ASE/EACVI 2016). MFS patients showed lower TDI e' velocities and higher average E/e' ratio, but still within normal range. Similarly, LVEF was normal but slightly reduced in MFS patients. LA strain and strain rate parameters during reservoir and conduit phase were significantly impaired in MFS patients compared to controls.

MFS vs controls MFS patients (n=40) Controls (n=20) p MFS patients (n=40) Controls (n=20) p Age 33.8±12.4 34.4±8.3 0.846 Septal e' (cm/s) 9.7±2.5 11.7±2.3 0.006 Male (%) 24 (60%) 12 (60%) 1.000 Average E/e' ratio 6.8±1.5 5.5±1.1 0.002 SBP (mmHg) 120.3±12.4 120.1±9.4 0.969 TR velocity (cm/s) 208.6±21.4 201.6±22.9 0.390 DBP (mmHg) 72.0±10.1 67.1±6.2 0.069 LAVi (ml/m2) 23.5±7.1 25.5±4.8 0.260 Aortic root (mm) 40.3±4.6 31.7±3.7 <0.001 LASr (%) 32.6±8.8 43.0±8.3 <0.001 LVEF (%) 60.9±5.6 64.2±4.2 0.022 LAScd (%) −20.1±8.0 −29.4±5.5 <0.001 E-wave (cm/s) 74.6±16.5 76.7±16.5 0.651 LASct (%) −12.8±6.1 −13.6±5.2 0.622 A-wave (cm/s) 55.2±10.9 52.0±12.8 0.327 LASRr 2.02±0.49 2.31±0.43 0.030 E/A ratio 1.4±0.4 1.5±0.4 0.287 LASRcd −2.22±0.61 −3.07±0.68 <0.001 Lateral e' (cm/s) 13.0±3.6 16.3±3.3 0.002 LASRct −2.24±0.90 −2.35±0.75 0.600 SBP: Systolic blood pressure. DBP: Diastolic blood pressure. LVEF: Left ventricular ejection fraction. LAVi: Left atrial volume index. LAS: Left atrial strain. LASR: Left atrial strain rate. (r): Reservoir. (cd): Conduit. (ct): Contraction.

Example of LA strain and strain rate

Conclusion

MFS patients showed a subtle impairment in diastolic function compared to controls. Although further evidence is needed, LAS derived parameters could be early markers of diastolic dysfunction in this group of patients.

Acknowledgement/Funding

Programa de Actividades de I+D de la Comunidad de Madrid

P1820New parameters for the evaluation of mechanic and elastic properties of the aortic root in Marfan Syndrome

Background

Elastic properties of the thoracic aorta in patients with Marfan Syndrome (MS) have already been evaluated with classic echocardiographic parameters. In the latest years the use of Speckle-Tracking (STE) ecocardiography has been widely extended. Our aim is to describe and provide new parameters of aortic deformation measured by STE in patients with MS.

Methods

95 unoperated adult patients with MS and 32 healthy controls were prospectively enrolled. We measured classic parameters of the aortic root using 2D echocardiography. We calculated the posterior aortic wall systolic excursion at the sinuses of Valsalva and ascending aorta using M Mode in TDI colour; with ST 2D ecocardiography we measured the aortic strain at the sinuses of Valsalva (SV) and the anterior and posterior aortic wall displacement at the SV. Aortic distensibility was calculated using the formula: 1000 * (Ds − Dd)/Dd * 1/(Ps − Pd) in mmHg–1 (Ds: systolic and Dd: diastolic diameters, Ps systolic and Pd diastolic blood pressure). Aortic stiffness index was calculated as Ln((Ps/Pd)/(Ds-Dd)/Dd)).

Results

As shown in the table bellow, patients with MS had lower aortic strain, aortic anterior and posterior wall displacement and impaired aortic distensibility and stiffness index compared to healthy controls. We found a strong negative linear correlation between aortic root diameter at the SV and aortic root strain (r=−0.56, figure 1).

Results of statistical analysis MS (n=95) Controls (n=32) p Age (years) 32.84±12.35 32.41±7.98 0.85 Aortic root diameter at the sinuses of Valsalva (mm) 38.82±5.35 30.92±3.65 <0.001 Aortic root strain (%) 4.66±2.45 9.19±2.49 <0.001 Anterior aortic wall displacement STE (mm) 10.39±3.64 13.10±2.26 <0.001 Posterior aortic wall displacement STE (mm) 9.02±2.87 11.04±1.82 <0.001 Aortic distensibility 0.98±0.46 1.37±0.72 0.01 Aortic stiffness index 3.74±0.43 3.47±0.51 0.01 MS = Marfan Syndrome; STE = Speckle Tracking Ecocardiography.

Figure 1. Dispersion plot

Conclusions

Our results suggest that aortic deformation and displacement obtained by STE echocardiography is impaired in MS, showing a reduced distensibility and an increased stiffness of the aortic wall, with a strong negative correlation between aortic root dilation and aortic strain. All these parameters may be useful as additional tools for the diagnosis and follow-up of Marfan patients, and could be useful to to improve the echocardiographic evaluation of the aortic root.

P4374Biventricular systolic function analysis in patients with Marfan Syndrome using speckle-tracking 2D ecocardiography

Background

Left Ventricular systolic disfunction has already been described in Marfan Syndrome (MS) in patients without valvular dysfunction using 2D and 3D speckle tracking echocardiography (STE). This dysfunction has been related to a more severe causal genetic mutation, which suggest the presence of a primary cardiomiopathy in these patients. Right ventricular function has been less studied so far. We sought to evaluate biventricular function in our cohort of MS patients with 2D-STE.

Methods

95 unoperated adult patients with MS and 32 healthy controls were prospectively enrolled. Patients with more than mild mitral or aortic regurgitation were excluded. Using STE we obtanied left ventricular global longitudinal strain (LVGLS) from the average of 16 segments from 4,2 and 3-chamber views and RVGLS values were obtained from the average of 6 segments from the apical 4-chamber view. We also measured classic parameters of systolic biventricular function (LVEF and TAPSE).

Results

Compared to controls, patients with MFS had significantly lower LVGLS and RVGLS (table 1). Values obtanied for LVGLS in MS patients were at the lower limit of normality stablished in the latest cuantification guidelines, while RVGLS and RV free wall LS were slightly above the limit of normality. LVEF and TAPSE were also slightly diminished in MS patients, though the differences found were clinically not relevant.

Results of statistical analysis MS (n=93) Controls (n=32) p Age (years) 32.84±12.4 32.41±7.98 0.85 Aortic Root Diameter Valsalva Sinuses (mm) 38.82±5.35 30.91±5.3 <0.001 LVGLS (%) −18.93±2.62 −21.52±2.26 <0.001 RVGLS (%) −21.25±3.54 −24.68±3.08 <0.001 RV free wall LS (%) −22.09±3.92 −25.56±3.63 <0.001 LVEF (%) 59.5±5.34 63.27±4.19 0.001 TAPSE (mm) 23.97±4.57 25.82±3.32 0.03 MS = Marfan Syndrome; LVGLS = Left ventricular global longitudinal strain; RVGLS = right ventricular global longitudinal strain.

Conclusions

Our study suggests that patients with MFS show lower biventricular strain compared with healthy controls. 2D-STE imaging may be useful to detect subclinical changes in cardiac function in patients with MFS and should be added to routine ecocardiographic evaluation in order to improve the follow-up and treatment of these patients.