Dynamic three-dimensional echocardiography combined with semi-automated border detection offers advantages for assessment of resynchronization therapy

Simultaneous electrical stimulation of both ventricles in patients with interventricular conduction disturbance and advanced heart failure improves hemodynamics and results in increased exercise tolerance, quality of life. We have developed a novel technique for the assessment and optimization of resynchronization therapy. Our approach is based on transthoracic dynamic three-dimensional (3D) echocardiography and allows determination of the most delayed contraction site of the left ventricle (LV) together with global LV function data. Our initial results suggest that fast reconstruction of the LV is feasible for the selection of the optimal pacing site and allows identifying LV segments with dyssynchrony

Hotline sessions presented at the American College of Cardiology Congress 2009

The article summarizes the results of clinical trials in the field of cardiovascular medicine, which were presented during the Hotline Sessions at the annual meeting of the American College of Cardiology in Orlando, USA, from 28th March to 31st March 2009. The data were presented by leading experts in the field with relevant positions within the trials. Unpublished reports should be considered as preliminary data as the analysis may change in the final publications. The summaries presented in the manuscript were generated from the oral presentations and provide the readers with the comprehensive information on the results of the latest clinical trials in cardiovascular medicine

The fusion band in V1: a simple ECG guide to optimal resynchronization? An echocardiographic case report

BACKGROUND: Patients with left bundle branch block have a preserved right bundle branch conduction and the efficacy of left ventricular pacing could be explained with the fusion between artificial pulse delivered in the left lateral wall and the spontaneous right ventricular activation. Moreover, the efficacy of left ventricular pacing could be enhanced with an optimal timing between the spontaneous right ventricular activation and the left ventricular pulse. CASE PRESENTATION: We evaluated a patient (male, 47 yrs) with surgically corrected mitral regurgitation, sinus rhythm and left bundle branch block, heart failure (NYHA class III) despite medical therapy and low ejection fraction (25%): he was implanted with a biventricular device. We programmed ventricular pacing only through the left ventricular lead. We defined what we called electrocardiographic "fusion band" as follow: programming OFF the stimulator, we recorded the native electrocardiogram and measured, through the device, the intrinsic atrioventricular interval. Then, atrioventricular interval was progressively shortened by steps of 20 ms down to 100 ms. Twelve leads electrocardiogram was recorded at each step. The fusion band is the range of AV intervals at which surface electrocardiogram (mainly in V1 lead) presents an intermediate morphology between the native left bundle branch block (upper limit of the band) and the fully paced right bundle branch block (lower limit). The patient underwent echocardiographic examination at each atrioventricular interval chosen inside the fusion band. The following parameters were evaluated: ejection fraction, diastolic filling time, E wave deceleration time, aortic velocity time integral and myocardial performance index. All the echocardiographic parameters showed an improvement inside the fusion band, with a "plateau" behaviour. As the fusion band in this patient ranged from an atrioventricular delay of 200 ms to an atrioventricular delay of 120 ms, we chose an intermediate atrioventricular delay of 160 ms, presuming that this might guarantee the persistence of fusion even during any possible physiological (autonomic, effort) atrioventricular conduction variation. CONCLUSION: In this heart failure patient with left bundle branch block, tailoring of the atrioventricular interval resynchronized myocardial contraction with left ventricular pacing alone, utilizing a sensed right atrial activity and the surface electrocardiographic pattern

Effective cardiac resynchronization therapy for an adolescent patient with dilated cardiomyopathy seven years after mitral valve replacement and septal anterior ventricular exclusion

Cardiac resynchronization therapy (CRT) is a new treatment for refractory heart failure. However, most heart failure patients treated with CRT are middle-aged or old patients with idiopathic or ischemic dilated cardiomyopathy. We treated a 17 year 11 month old girl with dilated cardiomyopathy after mitral valve replacement (MVR) and septal anterior ventricular exclusion (SAVE). Seven years after the SAVE procedure, she presented complaining of palpitations and general fatigue with normal activity. Her echocardiogram showed reduced left ventricular function. Despite of optimal medical therapy, her left ventricular function continued to decline and she experienced regular arrhythmias such as premature ventricular contractions. We thus elected to perform cardiac resynchronization therapy with defibrillator (CRT-D). After CRT-D, her clinical symptoms improved dramatically and left ventricular ejection fraction (LVEF) improved from 31.2% to 51.3% as assessed by echocardiogram. Serum BNP levels decreased from 448.2 to 213.6 pg/ml. On ECG, arrhythmias were remarkably reduced and QRS duration was shortened from 174 to 152 msec. In conclusion, CRT-D is an effective therapeutic option for adolescent patients with refractory heart failure after left ventricular volume reduction surgery

Cardiac Resynchronization Therapy in Patients with Mild Heart Failure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

# The Author(s) 2011. This article is published with open access at Springerlink.com Objective This review aims at updating the results of cardiac resynchronization therapy (CRT) in mild heart failure patients, and investigating whether CRT can prevent or reverse heart failure progression in an earlier stage. Methods Randomized controlled trials of CRT in patients with New York Heart Association (NYHA) Class I or II heart failure were identified. The effects of CRT on worsening heart failure hospitalization, all-cause mortality, and overall adverse events were meta-analyzed, and the effects of CRT on left ventricular (LV) were systematically reviewed and meta-analyzed. Results Eight studies were identified with a total of 4,302 patients. CRT was associated with a substantial improvement in LVend-systolic volume (WMD −39, 95%CI −41.56 to −36.45). CRT also had a marked effect in reducing new hospitalizations for worsening heart failure by 31 % (RR 0.69, 95%CI 0.60 to 0.79). In addition, CRTsignificantly decreased all-cause mortality by 21 % (RR 0.79, 95%CI 0.67 to 0.93). However, complications in patients with CRT increased by 74 % (RR 1.74, 95%CI 1.44 to 2.11). Conclusions This meta-analysis suggests that CRT could improve the prognosis in patients with mild heart failure and ventricular dyssynchrony, but these improvements are accompanied by more adverse events. Since most patients in the included trials had received ICD therapy, our analysis suggests that CRT could offer an additional benefit. Key words Heart failure. Cardiac resynchronization therapy. Meta-analysi

Successful reduction of intraventricular asynchrony is associated with superior response to cardiac resynchronization therapy

<p>Abstract</p> <p>Background</p> <p>Cardiac resynchronization therapy (CRT) is generally associated with a low to moderate increase of the left ventricular ejection fraction (LVEF). In some patients, however, LVEF improves remarkably and reaches near-normal values. The aim of the present study was to further characterize these so called 'super-responders' with a special focus on the extent of intra- and interventricular asynchrony before and after device implantation compared to average responders.</p> <p>Methods</p> <p>37 consecutive patients who underwent CRT device implantation according to current guidelines were included in the study. Patients were examined by echocardiography before, one day after and six months after device implantation. Pre-defined criterion for superior response to CRT was an LVEF increase > 15% after six months.</p> <p>Results</p> <p>At follow-up, eight patients (21.6%) were identified as super-responders. There were no significant differences regarding age, gender, prevalence of ischemic heart disease and LVEF between average and super-responders at baseline. After six months, LVEF had significantly increased from 26.7% ± 5.7% to 33.1% ± 7.9% (<it>p </it>< 0.001) in average and from 24.0% ± 6.7% to 50.3% ± 7.4% (<it>p </it>< 0.001) in super-responders. Both groups showed a significant reduction of QRS duration as well as LV end-diastolic and -systolic volumes under CRT. At baseline, the interventricular mechanical delay (IVMD) was 53.7 ± 20.9 ms in average and 56.9 ± 22.4 ms in super-responders - representing a similar extent of interventricular asynchrony in both groups (<it>p </it>= 0.713). CRT significantly reduced the IVMD to 20.3 ± 15.7 (<it>p </it>< 0.001) in average and to 19.8 ± 15.9 ms (<it>p </it>= 0.013) in super-responders with no difference between both groups (<it>p </it>= 0.858). As a marker for intraventricular asynchrony, we assessed the longest intraventricular delay between six basal LV segments. At baseline, there was no difference between average (86.2 ± 30.5 ms) and super-responders (78.8 ± 23.6 ms, <it>p </it>= 0.528). CRT significantly reduced the longest intraventricular delay in both groups - with a significant difference between average (66.2 ± 36.2 ms) and super-responders (32.5 ± 18.3 ms, <it>p </it>= 0.022). Multivariate logistic regression analysis identified the longest intraventricular delay one day after device implantation as an independent predictor of superior response to CRT (<it>p </it>= 0.038).</p> <p>Conclusions</p> <p>A significant reduction of the longest intraventricular delay correlates with superior response to CRT.</p

British randomised controlled trial of AV and VV optimization ("BRAVO") study:rationale, design, and endpoints

Background Echocardiographic optimization of pacemaker settings is the current standard of care for patients treated with cardiac resynchronization therapy. However, the process requires considerable time of expert staff. The BRAVO study is a non-inferiority trial comparing echocardiographic optimization of atrioventricular (AV) and interventricular (VV) delay with an alternative method using non-invasive blood pressure monitoring that can be automated to consume less staff resources. Methods/Design BRAVO is a multi-centre, randomized, cross-over, non-inferiority trial of 400 patients with a previously implanted cardiac resynchronization device. Patients are randomly allocated to six months in each arm. In the echocardiographic arm, AV delay is optimized using the iterative method and VV delay by maximizing LVOT VTI. In the haemodynamic arm AV and VV delay are optimized using non-invasive blood pressure measured using finger photoplethysmography. At the end of each six month arm, patients undergo the primary outcome measure of objective exercise capacity, quantified as peak oxygen uptake (VO2) on a cardiopulmonary exercise test. Secondary outcome measures are echocardiographic measurement of left ventricular remodelling, quality of life score and N-terminal pro B-type Natriuretic Peptide (NT-pro BNP). The study is scheduled to complete recruitment in December 2013 and to complete follow up in December 2014. Discussion If exercise capacity is non-inferior with haemodynamic optimization compared with echocardiographic optimization, it would be proof of concept that haemodynamic optimization is an acceptable alternative which has the potential to be more easily implemented

Sequential biventricular pacing improves regional contractility, longitudinal function and dyssynchrony in patients with heart failure and prolonged QRS

<p>Abstract</p> <p>Aims</p> <p>Biventricular pacing (BiP) is an effective treatment in systolic heart failure (HF) patients with prolonged QRS. However, approximately 35% of the patients receiving BiP are classified as non-responders. The aim of this study is to evaluate the acute effects of VV-optimization on systolic heart function.</p> <p>Methods</p> <p>Twenty-one HF patients aged 72 (46-88) years, QRS 154 (120-190) ms, were studied with echocardiography, Tissue Doppler Imaging (TDI) and 3D-echo the first day after receiving a BiP device. TDI was performed; during simultaneous pacing (LV-lead pacing 4 ms before the RV-lead) and during sequential pacing (LV 20 and 40 ms before RV and RV 20 and 40 ms before LV-lead pacing). Systolic heart function was studied by tissue tracking (TT) for longitudinal function and systolic maximal velocity (SMV) for regional contractility and signs of dyssynchrony assessed by time-delays standard deviation of aortic valve opening to SMV, AVO-SMV/SD and tissue synchronization imaging (TSI).</p> <p>Results</p> <p>The TT mean value preoperatively was 4,2 ± 1,5 and increased at simultaneous pacing to 5,0 ± 1,2 mm (p < 0,05), and at best VV-interval to 5,4 ± 1,2 (p < 0,001). Simultaneous pacing achieved better TT distance compared with preoperative in 16 patients (76%). However, it was still higher after VV-optimization in 12 patients 57%. Corresponding figures for SMV were 3,0 ± 0,7, 3,5 ± 0,8 (p < 0,01), and 3,6 ± 0,8 (p < 0,001). Also dyssynchrony improved.</p> <p>Conclusions</p> <p>VV-optimization in the acute phase improves systolic heart function more than simultaneous BiP pacing. Long-term effects should be evaluated in prospective randomized trials.</p