Outcome Of Cardiac Resynchronization Therapy Research Articles

R-Rʹ interval in the left bundle branch block predicts long-term outcomes after cardiac resynchronization therapy by estimating greater mechanical dyssynchrony and viable myocardium

BackgroundTypical left bundle branch block (LBBB) shows 2 peaks of the R wave, which reflect activation reaching the interventricular septum (R) and posterolateral wall (Rʹ) sequentially. ObjectiveThe purpose of this study was to investigate the relationship among R-Rʹ interval (RRʹ), mechanical dyssynchrony, extent of viable myocardium, and long-term outcomes in cardiac resynchronization therapy (CRT) candidates. MethodsThe study enrolled 49 patients (34 men; mean age: 69 ± 11 years) with LBBB who received CRT. The LBBB definition used requires the presence of mid-QRS notching in leads V1, V2, V5, V6, I, and aVL. Baseline evaluations were QRS duration (QRSd) and RRʹ measured from the 12-lead electrocardiogram; eyeball dyssynchrony (apical rocking and septal flash) and opposing-wall delay by speckle tracking from echocardiography, and extent of viable myocardium assessed by thallium-201 single-photon emission computed tomography. Primary outcomes included the combination of all-cause death and heart failure–related hospitalization. ResultsRRʹ predicted volumetric response better than QRSd (area under the curve 0.73 vs 0.67, respectively). The long RRʹ group (≥48 ms) revealed more frequent eyeball dyssynchrony and significantly greater radial (SL) and circumferential dyssynchrony (AP and SL) and %viable segment than the short RRʹ group. In multivariate regression analysis, only RRʹ ≥48 ms was independently associated with higher event-free survival rates following CRT (hazard ratio 0.21; P = .014). ConclusionThese findings suggest that RRʹ in complete LBBB was associated with mechanical dyssynchrony, extent of viable myocardium, and long-term outcomes following CRT.

A new method using deep transfer learning on ECG to predict the response to cardiac resynchronization therapy

Background: Cardiac resynchronization therapy (CRT) has emerged as an effective treatment for heart failure patients with electrical dyssynchrony. However, accurately predicting which patients will respond to CRT remains a challenge. This study explores the application of deep transfer learning techniques to train a predictive model for CRT response. Methods: In this study, the short-time Fourier transform (STFT) technique was employed to transform ECG signals into two-dimensional images. A transfer learning approach was then applied to the MIT-BIT ECG database to pre-train a convolutional neural network (CNN) model. The model was fine-tuned to extract relevant features from the ECG images and then tested on our dataset of CRT patients to predict their response. Results: Seventy-one CRT patients were enrolled in this study. The transfer learning model achieved an accuracy of 72% in distinguishing responders from non-responders in the local dataset. Furthermore, the model showed good sensitivity (0.78) and specificity (0.79) in identifying CRT responders. The performance of our model outperformed clinic guidelines and traditional machine learning approaches. Conclusion: The utilization of ECG images as input and leveraging the power of transfer learning allows for improved accuracy in identifying CRT responders. This approach offers potential for enhancing patient selection and improving the outcomes of CRT.

Outcomes of cardiac resynchronization therapy in congenital heart disease: A meta-analysis and systematic review.

Cardiac resynchronization therapy (CRT) is a standard treatment for patients with heart failure with reduced ejection fraction. However, there is still a gap of evidence in congenital heart disease (CHD) patients regarding resynchronization therapy. We performed a meta-analysis and systematic review of CHD patients who received CRT implantation. We comprehensively searched the databases of MEDLINE, EMBASE, and Cochrane database from inception to June 2023. Studies that reported response rate to CRT, total mortality rate, change in QRS duration, change in left ventricular ejection fraction, and change in New York Heart Association functional class were included. A total of 14 studies were included in the study. There were 10 studies that reported response rates after implantation. The overall response rate to CRT in CHD patients was 68% (95% confidence interval [CI] 61%-75%, I2 32%). The response rates in patients with systemic right ventricle (RV), systemic left ventricle (LV), and single ventricle were 58% (95% CI 46%-70%, I2 0%), 80% (95% CI 74%-86% I2 14%), and 67% (95% CI 49%-80% I2 0%). Response to CRT in systemic RV was inferior to systemic LV with an odds ratio of 0.38 (95% CI 0.15-0.95, I2 38%). The total mortality rate from sevenstudies was 12% (95% CI 8%-18%, I2 55%). The parameters which represented ventricular dyssynchrony improved after CRT implantation. The overall response rate to CRT in CHD was 68%. Patients with systemic RV had a lower response rate to CRT when compared to patients with systemic LV. The total mortality rate after CRT implantation was 12%.

Techniques for Cardiac Resynchronization Therapy in Patients with Congenital Heart Disease.

Cardiac resynchronization therapy (CRT) for congenital heart disease has shown promising suucess as an adjunct to medical therapy for heart failure. While cardiac conduction defects and need for ventricular pacing are common in congential heart disease, CRT indications, techniques and long term outcomes have not been well establaished. This is a review of the techniques nad short term outcomes of CRT for the following complex congenital heart disease conditions: single ventricle physiology, systemic right ventricle, and the subpulmonic right ventricle.

Improved outcomes of cardiac resynchronization therapy with a defibrillator in systolic heart failure: Analysis of the Japan cardiac device treatment registry database.

Temporal change in outcomes of heart failure patients receiving cardiac resynchronization therapy with a defibrillator (CRT-D) is unknown. We assess outcomes and underlying heart diseases of patients receiving CRT-D with analyzing database of the Japan cardiac device treatment registry (JCDTR) at the implantation year 2011-2015 and New JCDTR at the implantation year 2018-2021. Proportion of nonischemic heart diseases was about 70% in both the groups (JCDTR: 69%; New JCDTR: 72%). Cardiac sarcoidosis increased with the rate of 5% in the JCDTR to 9% in the New JCDTR group. During an average follow-up of 21 months, death from any cause occurred in 167 of 906 patients in the JCDTR group (18%) and 79 of 611 patients in the New JCDTR group (13%) (adjusted hazard ratio [aHR] in the New JCDTR group, 0.72; 95% confidence interval [CI]: 0.55-0.94; p = .017). The superiority was mainly driven by reduction in the risk of noncardiac death. With regard to appropriate and inappropriate implantable cardioverter-defibrillator (ICD) therapy, there was a significant reduction in the New JCDTR group versus the JCDTR group (aHR in the New JCDTR group, 0.76; 95% CI: 0.59-0.98; p = .032 for appropriate ICD therapy; aHR in the New JCDTR group, 0.24; 95% CI: 0.12-0.50; p < .0001 for inappropriate ICD therapy). All-cause mortality was reduced in CRT-D patients implanted during 2018-2021 compared to those during 2011-2015, with a significant reduction in noncardiac death.

A systematic review and meta-analysis of cardiac resynchronization therapy in inotrope-dependent heart failure: an update

Abstract Background Inotrope-dependent heart failure (HF) carries a poor prognosis. Advanced mechanical supports have been viewed as primary treatment modalities for these patients, but cardiac resynchronization therapy (CRT) is an emerging alternative. Whether CRT is viable in HF patients who require inotropic support is uncertain. Purpose To assess outcomes of CRT in end-stage inotrope-dependent HF. Methods Following PRISMA guidelines, we searched Medline, EMBASE, Scopus, and Cochrane Library until December 31st 2022, with the following terms: "end-stage heart failure," "catecholamine-dependent overt heart failure," "inotrope-dependent heart failure," "advanced heart failure," "New York Heart Association class IV," "NYHA class IV." These terms were combined with "cardiac resynchronization therapy" OR "CRT" OR "biventricular device". Studies were included if: 1) HF patients required on inotropic support at CRT implantation; 2) patients were at least 18 years old; and 3) provided a clear definition of "inotrope dependence" or "inability to wean." A meta-analysis with random effects was performed in R (Version 3.5.1) with data presented as mean ± standard error. Results 19 studies comprised of 386 inotrope-dependent HF patients (mean age 64.4 ± 1.2 years, 76.9% male, 54.6% non-ischemic cardiomyopathy, mean QRS duration 168.0 ± 4.6 ms, mean follow-up 778 ± 110.7 days) were included for meta-analysis. A large majority of patients survived until discharge at 90% (95% CI: 81.0%-96.8%, I2=51%, p=0.04, Figure 1A), 88.6% were weaned off inotropes (95% CI: 77.5%-96.8%, I2=64%, p&amp;lt;0.01), and mean time to discharge post-CRT was 7.8 days (95% CI: 3.9-11.7, I2= 84%, p&amp;lt;0.01). After one year of follow-up 69.5% survived (95% CI: 59.2%-78.9%, I2=53%, p=0.02, Figure 1B) and 59.1% (95% CI: 50.1%-67.8%, I2=58%, p&amp;lt;0.01, Figure 1C) were alive at the end of follow-up. During follow-up the mean number of hospital admission for HF was reduced by 1.87 (95% CI: 2.70-1.04, I2=77%, p=0.04). Post-CRT mean QRS duration was reduced by 29.0 ms (95% CI: 41.33-16.68, I2=69%, p=0.006, Fig) and mean left ventricular ejection fraction increased by 4.83% (95% CI: 3.09%-6.57%, I2=16%, p=0.31, Fig). The mean NYHA class post-CRT was 2.7 (95% CI: 2.5-3.0, I2=56%, p=0.03, Figure 2A), 39.6% (95% CI: 18,.7%-62.3%, I2=83%, p&amp;lt;0.01, Figure 2C) improved to NYHA class III and 34.6% (95% CI: 16.4%-55.2%, I2=79%, p&amp;lt;0.01, Figure 2D) improved to NYHA class II. Responders to CRT tended be male (85.7% vs. 40%, p=0.015), have a history of left bundle branch block (71.4% vs. 30%, p=0.036) or an increased left ventricular end-diastolic volume (274.3 mL vs. 225.9 mL, p=0.038). Conclusion(s) Our results suggest that CRT is an alternative option for end-stage inotrope-dependent HF, improving survival, NYHA status, and HF readmission. CRT responders appear to be male with evidence of preserved diastolic function or a history of a left bundle branch block.

Abstract 16791: Conduction System Response to Cardiac Resynchronization Therapy

Background: Cardiac resynchronization therapy (CRT) can be an effective treatment for cardiomyopathy patients with intraventricular conduction delay. However, significant controversy remains over the effect of QRS duration shortening on CRT outcomes. We hypothesize that reduction in QRS duration following CRT implantation is associated with echocardiographic outcomes. Methods: We included all adult patients with structural heart disease and CRT followed at UCLA. We reviewed all available electrocardiograms (ECG) and echocardiograms. We excluded patients with CRT for complete heart block, congenital heart disease, and those without intrinsic QRS ECGs prior to CRT. Patients were categorized as left bundle branch block (LBBB) if Strauss criteria were met prior to CRT implantation. Other patterns (including right bundle branch block with QRS duration ≥150ms) were classified as IVCD. We evaluated QRS duration before and immediately after CRT implantation. Changes in QRS duration post-CRT implant were calculated in percentage change. Echocardiograms were evaluated for changes in left ventricular end diastolic dimension (LVIDD) and ejection fraction (LVEF) following CRT implantation. Results: We included 108 patients (mean age of implant 66.1±12.8 years, 65% male, 63% nonischemic cardiomyopathy). Of these, 44 patients (41%) had LBBB. After CRT, patients with LBBB had significant decrease in QRS duration (-9.3±17.0% vs +16.9±30.9%, p &lt; 0.001), improvement in LVEF (12.1±10.5% vs 1.85±10.7%, p &lt; 0.001) and reduction in LVIDD (-0.6±0.7cm vs 0.1±0.7cm, p &lt; 0.001) compared to patients with IVCD. Decrease in QRS duration was significantly correlated with both improvement in LVEF (Pearson r = 0.21, p = 0.037) and reduction in LVIDD (Pearson r = 0.28, p = 0.006). Conclusion: CRT resulted in significantly larger decrease in QRS duration amongst patients with LBBB compared to IVCD. QRS duration reduction was, in turn, significantly correlated with improvements in LVIDD and LVEF. This likely reflects the proximal nature of true LBBB, and the ability of CRT to utilize the remaining distal Purkinje system for impulse propagation. Further research on the electrical and mechanical response to CRT can help guide optimization of target populations.

Cardiac CT in CRT as a Singular Imaging Modality for Diagnosis and Patient-Tailored Management.

Between 30-40% of patients with cardiac resynchronization therapy (CRT) do not show an improvement in left ventricular (LV) function. It is generally known that patient selection, LV lead implantation location, and device timing optimization are the three main factors that determine CRT response. Research has shown that image-guided CRT placement, which takes into account both anatomical and functional cardiac properties, positively affects the CRT response rate. In current clinical practice, a multimodality imaging approach comprised of echocardiography, cardiac magnetic resonance imaging, or nuclear medicine imaging is used to capture these features. However, with cardiac computed tomography (CT), one has an all-in-one acquisition method for both patient selection and the division of a patient-tailored, image-guided CRT placement strategy. This review discusses the applicability of CT in CRT patient identification, selection, and guided placement, offering insights into potential advancements in optimizing CRT outcomes.

Coronary artery complications with left bundle branch area pacing: A review of literature.

Left bundle branch area pacing (LBBAP) is an emerging technique in cardiac resynchronization therapy that shows promise in improving ventricular synchrony and clinical outcomes in patients with heart failure. However, the potential risk of coronary artery complications with LBBAP necessitates careful attention and management. This literature review explores the mechanisms, acute coronary events, and clinical implications associated with coronary artery complications in LBBAP. The mechanism of coronary injury with LBBAP involves mechanical trauma, altered coronary blood flow dynamics, and endothelial damage. Acute coronary events such as myocardial ischemia, acute coronary syndromes, and coronary artery dissection can occur during or after LBBAP, leading to significant clinical implications including the need for prompt intervention and potential impact on long-term outcomes. To avoid coronary injury and acute coronary syndrome with LBBAP, specific care strategies are recommended. These include thorough pre-procedural evaluation, expert operator technique, optimization of hemodynamics and ventricular synchrony, close monitoring for ischemic events, collaboration with cardiology specialists, and long-term follow-up. The clinical implications of coronary artery complications with LBBAP necessitate careful patient selection, informed decision-making, and a multidisciplinary approach. Future directions in this field include advancements in procedural techniques, technological innovations, risk stratification strategies, enhanced imaging modalities, research on mechanisms and prevention, and collaboration among stakeholders. By implementing these strategies and focusing on future advancements, healthcare providers can minimize the risk of coronary artery complications with LBBAP and optimize patient outcomes in cardiac resynchronization therapy.

Noninvasive Electrical Mapping Compared with the Paced QRS Complex for Optimizing CRT Programmed Settings and Predicting Multidimensional Response

The aim was to test the hypothesis that left ventricular (LV) and right ventricular (RV) activation from body surface electrical mapping (CardioInsight 252-electrode vest, Medtronic) identifies optimal cardiac resynchronization therapy (CRT) pacing strategies and outcomes in 30 patients. The LV80, RV80, and BIV80 were defined as the times to 80% LV, RV, or biventricular electrical activation. Smaller differences in the LV80 and RV80 (|LV80-RV80|) with synchronized LV pacing predicted better LV function post-CRT (p = 0.0004) than the LV-paced QRS duration (p = 0.32). Likewise, a lower RV80 was associated with a better pre-CRT RV ejection fraction by CMR (r = − 0.40, p = 0.04) and predicted post-CRT improvements in myocardial oxygen uptake (p = 0.01) better than the biventricular-paced QRS (p = 0.38), while a lower LV80 with BIV pacing predicted lower post-CRT B-type natriuretic peptide (BNP) (p = 0.02). RV pacing improved LV function with smaller |LV80-RV80| (p = 0.009). In conclusion, 3-D electrical mapping predicted favorable post-CRT outcomes and informed effective pacing strategies.Graphical

Sex-based differences in cardiac resynchronization therapy upgrade and outcome for patients with pacemaker and new-onset heart failure.

Patients with chronic right ventricular (RV) pacing are at an increased risk of heart failure. Previous studies have indicated that cardiac resynchronization therapy (CRT) is underused in this setting, and that there may be sex-based differences in both CRT use and clinical outcome. To evaluate sex-based differences in CRT use and clinical outcome for patients with new-onset heart failure post RV pacing. Data from the Swedish pacemaker registry was matched with data from the national death and disease registries. Patients with de novo pacemaker implant due to AV block during the period 2005-2020 were included. New-onset heart-failure within two years post-implant was evaluated, primary outcome was all-cause mortality. In all, 30183 patients (37% female) were included. Women were on average 3 years older, but had less comorbidities than men. Median follow-up time was 4.5 [2.0-8.0] years. Women had better age- and comorbidity-adjusted survival (HR 0.78 [0.73-0.84], p<.001). For the 3560 patients (12.4% men and 10.7% women, p<.001) who were diagnosed with new-onset heart failure, 5-year mortality was similar for men and women (50%vs. 48%, p=.29). However, women were less likely to receive CRT-upgrade (3.8%vs. 9.1%, p<.001), and those who did were almost ten years younger than the men. Women with pacemaker due to AV block are older but have less comorbidities than men. They are less likely to develop new-onset heart failure, but also less likely to receive a CRT upgrade if they do develop heart failure. Increased awareness of the positive effects of CRT upgrade and potential sex- and age-based discrimination is warranted.

Impact of Estimated Left Atrial Pressure on Cardiac Resynchronization Therapy Outcome.

We investigated the impact of baseline left atrial (LA) strain data and estimated left atrial pressure (LAP) by applying the 2016 American Society of Echocardiography and the European Association of Cardiovascular Imaging (ASE/EACVI) guidelines on cardiac resynchronization therapy (CRT) outcomes. Datasets of 219 CRT patients were retrospectively analysed. All patients had full echocardiographic diastolic function assessment before CRT and were classified based on the guideline algorithm into normal LAP (nLAP = 40%), elevated LAP (eLAP = 49%) and indeterminate LAP (iLAP = 11%). All relevant baseline characteristics were analysed. CRT-induced left ventricular (LV) reverse remodeling was measured as the relative change of LV end-systolic volume (LVESV) at 12 ± 6 months after CRT compared to baseline. Patients were followed up for all-cause mortality for a mean of 4.8 years [interquartile range (IQR): 2.7-6.0 years]. At follow-up, CRT resulted in more pronounced reduction of LVESV in patients with nLAP than in patients with eLAP. In univariate analysis, nLAP was associated with LV reverse remodelling (p < 0.001), as well as long-term survival after CRT (p < 0.01). However, multivariable analysis showed that only the association between nLAP and LV reverse remodelling after CRT is independent (p < 0.01). Adding LA strain analysis to the guideline algorithm improved the feasibility of LAP estimation without affecting the association between estimated LAP and CRT outcome. Normal LAP before CRT, estimated using the 2016 ASE/EACVI guideline algorithm, is associated with LV reverse remodelling and long-term survival after CRT. Albeit non-independent, it can serve as a non-invasive imaging-based predictor of effective therapy. Furthermore, the inclusion of LA reservoir strain in the guideline algorithm can enhance the feasibility of LAP estimation without affecting the association between LAP and CRT outcome.

A strain-based LBBB classification predicts the degree of reverse remodeling and outcome in patients with cardiac resynchronization therapy

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Research Foundation Flanders (FWO). Introduction Septal strain patterns measured by echocardiography reflect the gradual process of left bundle branch block (LBBB)-induced left ventricular (LV) remodeling. We investigated whether these strain stages also predict progressive volumetric response and outcome in cardiac resynchronization therapy (CRT) patients. Methods This prospective study enrolled consecutive CRT patients from 5 European centers who underwent echocardiographic examination with speckle-tracking strain analysis before CRT implantation. Dyssynchrony was assessed using septal strain curves, which were classified into 5 patterns (stage LBBB-0 to LBBB-4). The magnitude of reverse remodeling was determined at 1 year. The pre-defined outcome was death from any cause or heart transplantation. Results The study involved 267 patients (age 66±11 years; 69% men; 90% LBBB) with a mean LV ejection fraction (EF) of 30±7%. Across the stages, CRT resulted in a gradual volumetric response, ranging from almost no response in LBBB-0 patients (ΔLV end-systolic volume −9 ±21ml; ΔLVEF +4±8%) to super-response in LBBB-4 patients (ΔLV end-systolic volume −85 ±54ml; ΔLVEF +20±9%) (p&amp;lt;0.001 for both). Median follow-up was 49 months. LBBB-0 patients had worst outcome (log rank p = 0.002, Figure), with subsequent LBBB stages gradually showing more favorable outcome (log rank p = 0.045, Figure). There was a stepwise decrease in adverse events according to the staged LBBB classification. LBBB stages 1 to 4 predicted long-term survival without heart transplantation with respective hazard ratios of 0.61 (95% CI 0.25–1.50), 0.26 (95% CI 0.10–0.68), 0.29 (95% CI 0.11–0.77) and 0.13 (95% CI 0.04–0.51) compared to LBBB-0. After multivariable adjustment for baseline LVEF, ischemic heart disease and presence of an implantable cardioverter defibrillator, LBBB staging remained significantly associated with a decreased risk for adverse outcome (hazard ratio 0.69 (95% CI 0.51–0.92) per 1-stage increase). Conclusions Septal strain patterns are associated with the extent of reverse remodeling and outcome in CRT patients. The proposed LBBB classification provides pathophysiological insights in LBBB-induced LV dysfunction and may be helpful to identify patients who may benefit most from CRT implantation.

The prognostic value of non-invasively estimated left atrial pressure in patients undergoing cardiac resynchronization therapy

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union’s Horizon 2020 research and innovative program under the Marie Sklodowska -Curie grant agreement No. 860745. Background The impact of non-invasively estimated left atrial pressure (LAP) on cardiac resynchronization therapy (CRT) outcome has been previously investigated, yet with inconsistent results. Aim We aim at investigating the association between baseline LAP and CRT outcome applying both the standard guideline approach (Nagueh et al 2016) and the integrated guideline + LA strain approach. Methods Datasets of 219 CRT patients were retrospectively analyzed. All patients had full echocardiographic diastolic function assessment before CRT and were classified based on the guidelines approach for estimation of LAP into normal LAP (nLAP = 40%), elevated LAP (eLAP = 49%) and undetermined LAP (uLAP = 11%, when classification was not possible due to missing data, Figure A, solid bars). All baseline characteristics, comorbidities, and ECG data in addition to LA strain components before CRT were collected and analyzed. The amount of CRT-induced LV reverse remodeling was assessed at 12±6 months after CRT and was defined as percentage decrease of LV end-systolic volume (LVESV) compared to baseline. Patients were followed up for a mean of 4.8 years (interquartile range (IQR): 2.7–6.0) for all-cause mortality. Results Compared to patients with eLAP, patients with nLAP were more of female sex (40% vs. 21%) and they had lower serum creatinine (1.1 ± 0.4 vs. 1.5 ± 0.6 mg/dl). ECG data showed that they had less prevalence of AF (9 vs. 15%). All LA strain indices were better in patients with nLAP (23 ± 9 vs. 12 ± 7% for reservoir strain, 10 ± 4 vs. 7 ± 5% for conduit strain and 11 ± 7 vs. 4 ± 4% for pump strain, P &amp;lt; 0.01 for all comparisons). At follow-up, LVESV was reduced more in patients with nLAP than in patients with eLAP (47 ± 28 vs. 30 ± 30%, P &amp;lt; 0.01, figure B solid bars). Survival rates of patients with nLAP was significantly higher than patients with eLAP (Hazard ratio (HR): 0.40; confidence interval (CI): 0.22–0.27; P &amp;lt; 0.01, figure C solid lines). In the subgroup of uLAP an LA reservoir strain was used to further identify patients with nLAP (LA reservoir strain ≥ 18%). Accordingly, the integrated guideline+LA strain approach improved the feasibility for classification from 89% to 97%, where the percentage of the uLAP dropped from 11% to 3% (only patients with no baseline LA strain remained classified as uLAP, figure A). Patients with nLAP according to the integrated approach showed very similar CRT-induced LV reverse remodeling (figure B dashed bars) and long-term survival as compared to patients with nLAP according to the standard approach (figure C dashed lines). Conclusion Applying the standard guideline approach for LAP, patients with nLAP before CRT show more LV reverse remodeling and better long-term survival after CRT, as compared to patients with eLAP. The guideline + LA strain approach markedly improves the feasibility of LAP estimation, while not influencing the association between LAP and outcome after CRT.

Baseline creatinine level and long-term outcomes in patients with heart failure undergoing cardiac resynchronization therapy

Abstract Funding Acknowledgements Type of funding sources: None. Background Renal dysfunction has been shown as an independent predictor of mortality in patients with heart failure (HF). However, data on the long-term outcomes of cardiac resynchronization therapy (CRT) in patients with chronic kidney disease is scarce due to underrepresentation of such patients in clinical trials on CRT. Aim To determine outcome and mortality predictors in patients with HF and elevated creatinine level treated with cardiac resynchronization therapy. Methods Study population consisted of 1059 consecutive patients with CRT implanted between 2002 and 2019 in a tertiary care university hospital, in a densely inhabited, urban region of Poland (949 subjects [89.6%] with CRT-D; 110 patients with CRT-P [10.4%]; 832 men [78.6%]). Results The median creatinine level before CRT implantation was 96 umol/L (10th and 90th percentile: 67-160). We divided all CRT patients into quartiles per creatinine level: I &amp;lt;79 umol/L, II 79 to less than 96 umol/L, III 96 to less than 118 umol/L, and IV ≥118 umol/L. During the median follow-up of 1661 days (10th and 90th percentile: 323-3995), mortality rates for quartiles I-IV were 36.8, 44.9, 60.1, and 71.7%, respectively (P&amp;lt;0.05) [Figure 1]. The creatinine level ≥118 umol/L (quartile IV) appeared to be an independent risk factor for death (HR 1.004, 95%CI 1.003-1.006, P&amp;lt;0.001). On multivariable analysis, lower left ventricular ejection fraction (HR 0.97, 95%CI 0.95-0.99, P=0.04), higher NT-proBNP level (HR 1.00, 95%CI 1.0001-1.0005, P=0.04), and diabetes treated with insulin (HR 1.64, 95%CI 1.07-2.53, P=0.02) were independent risk factors for death in quartile IV. The mortality rate in those with creatinine level ≥118 umol/L and left ventricular ejection fraction ≤ 20% was 88% during the observation. Conclusions Compared to patients without renal dysfunction prior to CRT implantation, mortality rates of those with creatinine level ≥118 umol/L are significantly higher and reach 70% in 4.5 years of median observation. Almost 9 out of 10 CRT recipients with creatinine level ≥118 umol/L and left ventricular ejection fraction ≤ 20% die within 4.5 years since CRT implantation. Figure 1. Kaplan-Meier curves for survival of patients treated with cardiac resynchronization therapy as a function of creatinine level

Impact of gender on the utilization of cardiac implantable devices and outcome: results from the German DEVICE registry

Abstract Funding Acknowledgements Type of funding sources: None. Background Implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy (CRT) are widely used in patients with life-threatening cardiac arrhythmias or systolic heart failure. Real world data regarding gender impact on ICD and CRT implantation and outcome is scarce. Purpose To investigate the impact of gender-specific differences on cardiac devices implantation and outcomes. Methods The German DEVICE registry is a nationwide prospective multicentre database of ICD and CRT devices implantation. A total of 5451 patients were prospectively enrolled in 44 centres between March 2007 and February 2014 and were monitored for a median of 17 months. Results A minority of patients in this registry was female 1050 (19.3%; mean age 64.4 ± 14.6 years; median BMI 27.2) while men represented 80.7% (mean age 65.5 ± 12.4 years; median BMI 26.8). Female patients were less likely to have a LVEF &amp;lt;35% (70.6% vs. 77.7%; p&amp;lt;0.0001) and more likely to have a LVEF &amp;gt;55% (13.3% vs. 6.6%; p&amp;lt;0.0001). Moreover, women were less likely to have coronary artery disease (42.3% vs. 64.7%; p&amp;lt;0.0001), history of myocardial infarction, percutaneous coronary intervention, and coronary artery bypass graft (p&amp;lt;0.0001 for all). The rate of CRTs was significantly higher in women than in men (33.4% vs. 28.7%; p=0.0036). In terms of secondary prevention implantations, women were more likely to have history of ventricular fibrillation (VF; 50.7% vs. 37.2%; p&amp;lt;0.0001) but less likely to have history of ventricular tachycardia (VT; 34.5% vs. 47.5%; p&amp;lt;0.0001). The rates of major periprocedural complications and in-hospital complications were higher in women (3.3% vs. 1.7%; p=0.002 and 5.6% vs. 3.7%; p=0.0208). The Kaplan-Meier estimated 1-year all-cause mortality was 5.4% for women and 7.4% for men, while the overall mortality during follow-up was 10% for women and 14% for men (p=0.0004), with no gender differences in terms of death cause. Significantly less women received device shocks (14.2% vs. 17.5%; p=0.0260), while more women needed device revision during follow-up (10.9 % vs. 8.2%; p=0.0246). Similar rates of primary and secondary prevention indication were noted for female and male patients (p=0.9717). There was no difference between the groups regarding the need of postprocedural system revision (p=0.7884), as well as in-hospital death, cardiac death, or sudden cardiac death. The non-fatal complications during follow-up were comparable for men and women. Moreover, similar rates and durations of all cause and cardiac rehospitalizations were found (p=0.1644 and p= 0.1816). Conclusion In this real-life patient cohort only a minority of female patients were enrolled. Female patients were more likely to undergo CRT implantation and had a higher risk for acute major periprocedural complications and in-hospital complications but a lower overall mortality in 1-year follow-up. However, the differences in baseline characteristics should be considered as potential confounders.

Cardiac resynchronization therapy guided by activation mapping in non-left bundle branch block patients

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Various studies have questioned the magnitude of the benefit of cardiac resynchronization therapy (CRT) in patients without left bundle branch block (LBBB). This worse response could be due to the suboptimal location of the electrodes. Purpose We hypothesize that in non-LBBB patients, an implant guided by ventricular electroanatomic mapping by locating the areas with the greatest activation delay will improve the outcome of CRT. Material and methods We included 7 patients non-LBBB. To locate the most delayed activation zones, an electromagnetic activation map was created using the Ensite Precision navigator connected to the right ventricular catheter and to a guidewire with electrical recording capacity at its distal end. ECG, clinical, and echocardiographic data were recorded at baseline and post-implantation, compared with 7 patients LBBB (control group). Results In non-LBBB patients, several activation patterns could be defined according to the conduction disorder, including right bundle branch block (RBBB)+left anterior hemiblock (figure 1A) or RBBB alone (figure 1B). All patients with non-LBBB improved at follow-up in the NYHA functional class (p=0,011) and in the Minnesota test (7,85±4,63; p=0.004). The mean reduction in QRS duration was 14,57±9,86 ms (p=0.008), LVEF increased 8.22±4.62 ms (p=0.003), LVOTS decreased by 15,71±12,23 ml (p=0.015) and the LVEDV in 10,42±5,15 ml (p=0.002). There were no significant differences between the response to CTR in non-LBBB patients and LBBB patients (table 1), including LVEF (8.22±4.62 vs 11.54±5.54, p=0.248) and difference in Minnesota test (7.85±4.63 vs 9.71±5.87, p=0.524). Conclusions CRT guided by electroanatomical mapping produced significant clinical and structural improvement in non-LBBB patients. This improvement was of a similar magnitude to LBBB patients. Various patterns of ventricular activation according to the conduction disorder were observed.

Prognostic value of nutritional status in post-implant CRT outcomes in patients with chronic heart failure

Abstract Funding Acknowledgements Type of funding sources: None. Introduction There’s a close relationship between chronic heart failure (CHF) and malnutrition, and their main pathophysiological modifications are well known. Cardiac resynchronization therapy (CRT) has proven to be a promising therapy in symptomatic heart failure (HF) patients with broad QRS complexes and impaired systolic function with optimized medical therapy. However, there is still a considerable amount of non-responder patients. The role of nutritional status in CRT therapy response has yet still not been well assessed. Purpose Assess the prognostic value of nutritional status in post-op outcomes in patients with Chronic Heart Failure and (CRT) Methods Single-center retrospective study of patients submitted to CRT implantation between January 2007 and march 2021. Inclusion criteria were patients meeting criteria for CRT implantation, QRS duration ≥ 120ms, FEVE ≤ 35%, NYHA class II–IV and no adverse events during the follow up. Primary outcomes measured were all-cause mortality, cardiovascular mortality, and hospitalizations due to HF in a 1-year follow-up. To evaluate patient's nutritional status the CONUT score was used with patients being categorized in 2 groups: Low CONUT (Score 0-4: normal/low malnutrition) and Hight CONUT (Score 5-12: moderate/severe malnutrition). Results 198 patients (83%) exhibited Low CONUT status, and 41 patients (17%) exhibited High CONUT status. Patients with Hight CONUT were older (72.9 yrs vs 65.9 yrs, p&amp;lt;0.001), and exhibited higher percentage of chronic obstructive pulmonary disease (43.9% vs 27.3%, p=0.004), atrial fibrillation (72.9%, vs 25.3%, p&amp;lt;0.001), hypertension (78.1% vs 60.6%, p=0.038), chronic kidney disease (39.1% vs 21.2%, p=0.016) and NYHA IV (19.5% vs 5.1%, p&amp;lt;0.001). Cardiovascular mortality was 3.7% in the low CONUT group vs 29.3% in the Hight CONUT group (p&amp;lt;0.001; HR, 0.12; 95% CI, 0.05-0.29) and total HF hospitalizations were 16 and43, respectively (p=0.013; HR, 0.482, 95% CI, 0.27 to 0.86). The nutritional status prior to CRT assessed by the CONUT score showed to be an independent predictor of cardiovascular mortality (p=0.007; HR, 0.16 95% CI, 0.04-0,60). Conclusion Malnutrition was a common condition in our CRT patients showing that deficient nutrition status remains highly underdiagnosed. Patients with worse nutritional status before CRT device implantation presented higher morbidity and were more prone to worst outcomes such as cardiovascular mortality and mortality by all causes as well as higher incidence of hospitalizations secondary to HF decompensation. Assessment of nutritional status using screening tools may provide additional prognostic information in patients with HF and help early identification of those who may benefit from further assessment and nutritional intervention.

Association between left ventricular lead position and intrinsic QRS morphology with regard to clinical outcome in cardiac resynchronization therapy for heart failure.

Left ventricular (LV) lead position may be an important factor for delivering effective cardiac resynchronization therapy (CRT). We therefore aimed to evaluate the effects of LV lead position, stratified by native QRS morphology, regarding the clinical outcome. A total of 1295 CRT-implanted patients were retrospectively evaluated. LV lead position was classified as lateral, anterior, inferior, or apical, and was determined using the left and right anterior oblique X-ray views. Kaplan Meier and Cox regression were performed to evaluate the effects on all-cause mortality and heart failure hospitalization, and the potential interaction between LV lead position and native ECG morphologies. A total of 1295 patients were included. Patients were aged 69 ± 7 years, 20% were female, 46% received a CRT-Pacemaker (vs. CRT-Defibrillator), mean LVEF was 25% ± 7%, and median follow-up was 3.3 years [IQR 1.6-5-7 years]. Eight hundred and eighty-two patients (68%) had a lateral LV lead location, 207 (16%) anterior, 155 (12%) apical, and 51 (4%) inferior. Patients with lateral LV lead position had larger QRS reduction (-13 ± 27 ms vs. -3 ± 24 ms, p < .001). Non-lateral lead location was associated with a higher risk for all-cause mortality (HR 1.34 [1.09-1.67], p = .007) and heart failure hospitalization (HR 1.25 [1.03-1.52], p = .03). This association was strongest for patients with native left or right bundle branch block, and not significant for patients with prior paced QRS or nonspecific intraventricular conduction delay. In patients treated with CRT, non-lateral LV lead positions (including apical, anterior, and inferior positions) were associated with worse clinical outcome and less reduction of QRS duration. This association was strongest for patients with native LBBB or RBBB.

Effects of Atrioventricular Optimization on Left Ventricular Reverse Remodeling With Cardiac Resynchronization Therapy: Results of the SMART-CRT Trial.

The role of atrioventricular optimization (AVO) to improve cardiac resynchronization therapy outcomes remains controversial. Previous post hoc analyses of a multicenter trial showed that measures of electrical dyssynchrony (right ventricular-left ventricular [LV] or QLV durations) are associated with patients who benefit from AVO. This was a global, multicenter, prospective, randomized trial of de novo cardiac resynchronization therapy implant patients with an right ventricular-LV duration ≥70 ms to determine whether AVO results in greater reverse remodeling. Patients were randomized 1:1 for either an AVO algorithm (SmartDelay) that determines atrioventricular delay and pacing chamber, biventricular or LV only, or a fixed atrioventricular delay of 120 ms with biventricular pacing. Paired echocardiograms performed at baseline and 6 months were evaluated. The primary end point was echocardiographic cardiac resynchronization therapy response, defined dichotomously as a >15% reduction in LV end-systolic volume. A total of 310 patients (n=120 women) were randomized and had completed 6 months of follow-up. The echocardiographic cardiac resynchronization therapy response rate did not statistically differ between the groups (SmartDelay, 74.8%; fixed, 67.7%; P=0.17). Analyses of prespecified secondary end points demonstrated significant improvements in the absolute (median: SmartDelay, -41.0 mL; fixed, -33.0 mL; P=0.01) and relative change in LV end-systolic volume (SmartDelay, -38.3%; fixed, -27.8%; P=0.03) for patients with SmartDelay optimization. Similar results were observed for the relative improvement in LV ejection fraction (SmartDelay, 46.7%; fixed, 32.1%; P=0.050); absolute improvement in LV ejection fraction trended to be higher with SmartDelay (P=0.06). Analysis of reverse remodeling parameters demonstrated that AVO via SmartDelay, relative to the nonoptimized fixed atrioventricular delay comparator group, improved absolute and relative changes in LV function in patients with longer right ventricular-LV duration. URL: https://www. gov; Unique identifier: NCT03089281.