Raymond Roudaut

Automated function imaging: a new operator-independent strain method for assessing left ventricular function.

BACKGROUND Speckle tracking is a new technique based on pure 2D grayscale ultrasound acquisition allowing calculation of segmental strains. To facilitate clinical application, speckle tracking has been integrated into the most recent echocardiographic systems for quick, automated evaluation of left ventricular function (Automated Function Imaging, AFI). OBJECTIVE To evaluate the feasibility, calculation time, accuracy and reproducibility of global longitudinal strain (GLS) from AFI in determining LV function in comparison to reference echocardiographic and angiographic methods-whatever the operators experience. METHODS Echocardiography was performed in 65 patients scheduled for cardiac catheterization using a Vivid 7 system. They were divided into 3 groups according to EF (>55%, 35< or =EF< or =55%,<35%). Image quality, global LV function parameters (ejection fraction, aortic flow, dp/dt) and segmental contraction were analyzed by one experienced operator and one beginner. GLS was obtained from apical 2, 3 and 4 chamber views. GLS was compared to both echocardiographic and angiographic EF, as well as to other echocardiographic parameters. RESULTS GLS was obtained successfully in 97% of patients. Mean calculation time including correction of endocardial detection was less than 60 seconds. GLS was significantly different between the 3 groups, respectively -18.1+/-2.5%, -11.5+/-2.1% and -6.0+/-1.2% (p<0.01). Strong correlations were observed between GLS and LV function (r from 0.68 to 0.87) with a high level of reproducibility. No difference was observed between experienced and inexperienced operators. CONCLUSION AFI is clinically applicable and an effective means of assessing LV function due to its short acquisition time, feasibility and accuracy, whatever the experience of the operator.

Validation of an echocardiographic multiparametric strategy to increase responders patients after cardiac resynchronization: a multicentre study

AIMS We sought to develop and validate a multiparametric algorithm by applying previously validated criteria to predict cardiac resynchronization therapy (CRT) response in a multicentre study. Thirty per cent of patients treated by CRT fail to respond to the treatment. Although dyssynchrony by echocardiography has been used to improve the selection of patients, the complexity of myocardial contraction has generated a moderate improvement using any of several individual parameters. METHODS AND RESULTS Two hundred end-stage heart failure patients [NYHA 3-4 and left ventricular ejection fraction (LVEF)<35%] with QRS>120 ms were included. Echocardiography analysis focused on the following parameters: atrioventricular dyssynchrony, interventricular dyssynchrony, and intraventricular dyssynchrony that integrated radial (PSAX M-mode) and longitudinal [tissue Doppler imaging (TDI)] evaluations for spatial (wall to wall) and temporal (wall end-systole to mitral valve opening) dyssynchrony diagnosis. Following CRT implantation, patients were monitored for 6 months with functional and echo evaluations defining responders by a 15% reduction in end-systolic volume. Mean QRS duration and LVEF were 152 +/- 17 ms and 25 +/- 8%. There was a CRT response in 57% of patients, independent of QRS width. Mean prevalence of positive criteria was 34 +/- 8%. Feasibility and variability averages were 81 +/- 20% and 9 +/- 4%. In a single parametric approach, ranges of sensitivities and specificities were 18-65% and 45-84% with a mean of 41% and 66%. A multiparametric approach by focusing on criteria combination decreased the mean rate of false-positive results to 14 +/- 12%, 5 +/- 4%, 2 +/- 2%, and 1 +/- 2% from one to four parameters, respectively. More than three parameters were associated with a specificity above 90% and a positive predictive value above 65%. Reproducibility of this global strategy was 91%. CONCLUSION A multiparametric echocardiographic strategy based on the association of conventional criteria is a better indicator of CRT response than the existing single parametric approaches.

Efficacy and follow-up of transcatheter aortic valve implantation in patients with radiation-induced aortic stenosis

Objective To investigate transcatheter aortic valve implantation (TAVI) feasibility, effectiveness and safety in radiation-induced aortic valve stenosis cases. Methods 198 consecutive patients referred for TAVI were prospectively enrolled. They were divided into two groups: patients with a history of chest radiation therapy with suspected radiation-induced valvular disease (RXT) and others with suspected degenerative aortic valve stenosis (NRXT). Procedural, early and mid-term clinical outcomes were compared. Results Of the 198 patients enrolled in our study, 9.6% qualified for inclusion in the RXT group. A comparison of baseline characteristics revealed that patients with RXT were younger than patients with NRXT (68.3 vs 82.5 years; p<0.05) and exhibited a lower surgical risk score (Euroscore: 7.1% vs 21.8%; p<0.05) and a higher frequency of hostile thorax and porcelain aorta (52.6% vs 28.5%; p<0.05; 63.2% vs 10.6%; p<0.05, respectively). In both groups, the implantation success rate was high and the 30-day safety end point acceptable (RXT: 94.7% and 83.3%; NRXT: 93.9% and 75.6%, respectively). At 6 months, overall mortality was significantly lower in the RXT group (0% vs 18%; p=0.048). Conclusions In patients suffering from radiation-induced aortic valve stenosis and contraindicated for surgery, TAVI is a promising approach, with high feasibility, acceptable risk, low mortality and high clinical effectiveness at mid-term follow-up.

Can Power Motion Imaging Mode Combined with Contrast Agent Assess Myocardial Contraction and Perfusion? In Vitro and In Vivo Studies

Power motion imaging (PMI) is a new Doppler imaging technology that can enhance contrast agent visualization. We hypothesized that PMI combined with Albunex injection (CPMI) could provide new insights into myocardial contractility and perfusion. In a first step, PMI signal was studied with an in vitro phantom. In a second step, PMI signal was studied in 10 rabbits at different workloads. In a third step, 10 rabbits were studied before and after ischemia produced by coronary ligation and finally during reperfusion. During the latter protocol, epicardial echocardiography analyzed by PMI and fundamental mode was performed before and after Albunex injection. PMI signal was well correlated with phantom velocity. PMI signal and myocardial wall thickening were well correlated, particularly in the septal area. On the coronary occlusion model, ischemia was associated with a significant decrease in PMI and CPMI signals, whereas reperfusion was associated with a significant decrease in PMI signals only, indicating stunning. We conclude that PMI combined with CPMI is a powerful tool to assess myocardial contractility and perfusion.

970 Successful catheter ablation of chronic atrial fibrillation is associated with diastolic mechanical remodeling of the left heart

19.2±4.8 36±6.7 p<0.0001 Mean LV enddiastolic filling pressure (mmHg) 24.7±6.2 14.9±5.1 p<0.001 Mean LA emptying fraction (%) 14.2±7.6 26.8±9.2 p<0.005 Mean LA area variation (cmsq/%) 4.1±2.8 2.8±1.7 p<0.01 (72.6±15.2) (42.7±7.2) (p<0.0001) Mean area variation during 1.78±1.2 3.62±1.6 p<0.0001 the LA contraction (cmsq/%) (42.8±13.9) (69.2±21.3) (p<0.0001) LA maximal area (cmsq) 36.2±6.8 24.3±3.2 p<0.0001 LVEF - left ventricle ejection fractionLA - left atriumLV - left ventricle Conclusions: 1.Patients with ischemic cardiomyopathy and restrictive LV dias- tolic filling pattern have LA dimensions significantly higher and LA dysfunction with smaller LA emptying fraction and LA area variation during the LA contraction. 2.Be- cause LA has an important role in LV filling, the LA dysfunction and dilatation are important markers for unfavourable prognostic, increasing the early and long term postoperative risk of death.