Cardiac Resynchronization Therapy Upgrade Research Articles

The Suboptimal QLV Ratio May Indicate the Need for a Left Bundle Branch Area Pacing-Optimized Cardiac Resynchronization Therapy Upgrade

The Suboptimal QLV Ratio May Indicate the Need for a Left Bundle Branch Area Pacing-Optimized Cardiac Resynchronization Therapy Upgrade

Leadless Ultrasound-Based Cardiac Resynchronization System in Heart Failure

Approximately 40% of patients with heart failure (HF) who are eligible for cardiac resynchronization therapy (CRT) either fail to respond or are untreatable due to anatomical constraints. To assess the safety and efficacy of a novel, leadless, left ventricular (LV) endocardial pacing system for patients at high risk for a CRT upgrade or whose coronary sinus (CS) lead placement/pacing with a conventional CRT system failed. The SOLVE-CRT study was a prospective multicenter trial, enrolling January 2018 through September 2022, with follow-up in March 2023. Data were analyzed from DATE MONTH, YEAR, through DATE MONTH, YEAR. The trial combined data from an initial randomized, double-blind study (n = 108) and a subsequent single-arm part (n = 75). It took place at 36 centers across Australia, Europe, and the US. Participants were nonresponders, previously untreatable (PU), or high-risk upgrades (HRU). All participants contributed to the safety analysis. The primary efficacy analysis (n = 100) included 75 PU-HRU patients from the single-arm part and 25 PU-HRU patients from the randomized treatment arm. Patients were implanted with the WiSE CRT System (EBR Systems) consisting of a leadless LV endocardial pacing electrode stimulated with ultrasound energy delivered by a subcutaneously implanted transmitter and battery. The primary safety end point was freedom from type I complications. The primary efficacy end point was a reduction in mean LV end systolic volume (LVESV). The study included 183 participants; mean age was 68.1 (SD, 10.3) years and 141 were male (77%). The trial was terminated at an interim analysis for meeting prespecified stopping criteria. In the safety population, patients were either New York Heart Association Class II (34.6%) or III (65.4%). The primary efficacy end point was met with a 16.4% (95% CI, -21.0% to -11.7%) reduction in mean LVESV (P = .003). The primary safety end point was met with an 80.9% rate of freedom from type I complications (P < .001), which included 12 study device system events (6.6%), 5 vascular events (2.7%), 3 strokes (1.6%), and 7 cardiac perforations which mostly occurred early in the study (3.8%). The SOLVE-CRT study has demonstrated that leadless LV endocardial pacing with the WiSE CRT system is associated with a reduction in LVESV in patients with HF. This novel system may represent an alternative to conventional CRT implants in some HF patient populations. ClinicalTrials.gov Identifier: NCT0292203.

Benefits of upgrading right ventricular to biventricular pacing in heart failure patients with atrial fibrillation.

Recommendations on cardiac resynchronization therapy (CRT) in patients with atrial fibrillation or flutter (AF) are based on less robust evidence than those in sinus rhythm (SR). We aimed to assess the efficacy of CRT upgrade in the BUDAPEST-CRT Upgrade trial population by their baseline rhythm. Heart failure patients with reduced ejection fraction (HFrEF) and previously implanted pacemaker (PM) or implantable cardioverter defibrillator (ICD) and ≥20% right ventricular (RV) pacing burden were randomized to CRT with defibrillator (CRT-D) upgrade (n = 215) or ICD (n = 145). Primary [HF hospitalization (HFH), all-cause mortality, or <15% reduction of left ventricular end-systolic volume] and secondary outcomes were investigated. At enrolment, 131 (36%) patients had AF, who had an increased risk for HFH as compared with those with SR [adjusted hazard ratio (aHR) 2.99; 95% confidence interval (CI) 1.26-7.13; P = 0.013]. The effect of CRT-D upgrade was similar in patients with AF as in those with SR [AF adjusted odds ratio (aOR) 0.06; 95% CI 0.02-0.17; P < 0.001; SR aOR 0.13; 95% CI 0.07-0.27; P < 0.001; interaction P = 0.29] during the mean follow-up time of 12.4 months. Also, it decreased the risk of HFH or all-cause mortality (aHR 0.33; 95% CI 0.16-0.70; P = 0.003; interaction P = 0.17) and improved the echocardiographic response (left ventricular end-diastolic volume difference -49.21 mL; 95% CI -69.10 to -29.32; P < 0.001; interaction P = 0.21). In HFrEF patients with AF and PM/ICD with high RV pacing burden, CRT-D upgrade decreased the risk of HFH and improved reverse remodelling when compared with ICD, similar to that seen in patients in SR.

Comparative analysis of clinical outcomes in patients undergoing primary CRT implantation versus CRT upgrade: single center experience

Abstract Background As heart failure (HF) management evolves, cardiac resynchronization therapy (CRT) has emerged as a cornerstone intervention, improving left ventricular (LV) function and reducing morbidity and mortality. The Budapest trial specifically addressed upgrading from permanent pacemaker (PPM) to CRT, emphasizing the potential for improved clinical outcomes and quality of life in this population. The findings highlighted the impact of CRT upgrade and contribute valuable insights to the cardiac device strategies for HF patients. This study aims to compare clinical outcomes between patients undergoing primary CRT implantation and those undergoing CRT upgrade. Methods A retrospective analysis was conducted on a cohort of heart failure patients who received CRT devices between 2015 and 2019. Patients were categorized into two groups: those undergoing primary CRT implantation and those undergoing CRT upgrade. Clinical outcomes, including mortality rate, hospitalization for HF exacerbation, and improvements in left ventricular ejection fraction (LVEF), were assessed and compared between the two groups. Results A total of 847 patients were included in the study, with 74,5% (n=631) undergoing primary CRT implantation and 13,5% (n=114) receiving CRT upgrades. The mean age was 72±10 years-old and 57% (n=485) were women, and a mean follow-up time of 23±8 months. 33.7% (n=285) of the total were of ischemic etiology. The primary CRT implantation group demonstrated a mortality of 34% (n=215) and 13% (n=84) of hospitalization due to HF; NYHA functional class improvement in 58% (n=369), and 35,7% (n=225) were CRT responders with a mean LV ejection fraction (EF) improvement of ±10%, while the CRT upgrade group had a 31% (n=36) mortality and 19% (n=22) of hospitalization due to HF; NYHA functional class improvement in 60% (n=68), and 27% (n=31) were CRT responders with a mean LV EF improvement of 8,7%. There were no statistically significant differences regarding each endpoint, namely mortality, HF hospitalizations, NYHA functional class improvement, CRT responders and mean LVEF improvement. Conclusion A clear benefit from implantation of a primary CRT device implantation has already been demonstrated. However, recent trials revealed there was also benefit in upgrading from PPM to CRT patients with decrease LVEF, comparing with PPM. This study showed that the benefits from primary CRT were similar to the benefits from upgrading CRT, in terms of mortality reduction, HF hospitalizations, NYHA functional class improvement, CRT responders and mean LVEF improvement. Once again, just like in the most recent trials, this study demonstrates the clear benefit of upgrading from a PPM to CRT in patients with decreased LVEF.

The effect of cardiac resynchronisation therapy upgrade from right ventricular pacing on symptoms and functional clinical outcomes, results from the BUDAPEST-CRT Upgrade trial

Abstract Background Based on the results of the BUDAPEST-CRT Upgrade trial, in patients with intermittent or permanent right ventricular (RV) pacing and reduced left ventricular ejection fraction (HFrEF) upgrade to cardiac resynchronization therapy (CRT) reduces morbidity and mortality. Purpose Whether the substantial treatment effect of the CRT upgrade could also be detected in a better functional and exercise capacity is scarcely investigated. We examined the changes of the prespecified tertiary endpoints such as symptoms, quality of life (QoL), exercise capacity and natriuretic peptide measurement from baseline to 12 months. Methods In the BUDAPEST CRT Upgrade trial 360 HFrEF patients with a priorly implanted PM or ICD and &amp;gt;20% of RV pacing burden were randomly assigned to CRT-D upgrade (n=215) or ICD (n=145) in a 3:2 ratio. The prespecified tertiary endpoints were changes in quality of life measured by EQ-5D-3L, New York Heart Association (NYHA) functional class, 6-minute walk test (6-MWT), and NT-proBNP. When data of trial patients were unavailable due to death at 12 months, imputed values were used as 0 (6MWT) and 0 score (EQ-5D-3L) or a 5th grade (NYHA class). Responders were defined as &amp;gt;15% change of left ventricular end-systolic volume at 12 months. Results From baseline to 12 months, NYHA functional class improved in the CRT-D upgrade arm compared with the ICD only group [adjusted odds ratio (OR) 0.50; 95% CI 0.32-0.80; P=0.003]. According to the adjusted model there was a statistically significant decrease in the NT-proBNP [adjusted difference -1257 pg/mL; 95% CI -2287 – (-228); P=0.017]. In responders, the changes in NT-proBNP levels were significantly greater than in non-responders [adjusted difference -1635 pg/mL; 95% CI -2811 - (-459); P=0.007]. The progression of worsening of QoL attributed to ageing was moderated only by CRT-D upgrade [EQ-5D-3L difference by age -0.01; 95% CI -0.02 - (-0.003); P=0.004; interaction P=0.003]. 6MWT did not improve significantly in either group. Conclusions Patients receiving CRT upgrade showed a substantial improvement in symptoms and a significant decrease in natriuretic peptide levels, as compared to ICD alone, which was more pronounced in responders. Moreover, CRT-D upgrade could moderate the progression of worsening of quality of life attributed to ageing in this vulnerable, older patient population.

Heart rate is an important predictor of pacing induced cardiomyopathy in a machine learning analysis

Abstract Background 10-20% of patients who have right ventricular pacing develop pacing induced cardiomyopathy (PICM). Home monitoring (HM) could identify patients developing PICM in real-time and facilitate echocardiographic confirmation, medication optimisation and if necessary cardiac resynchronisation therapy (CRT). Purpose To identify predictors of PICM using machine learning models. Methods Consecutive cases of patients who developed PICM (12) after dual chamber pacing were identified from our implant database and matched 4:1 with propensity matched controls who underwent pacing but did not develop PICM (48) (Table 1.) HM data from the 6 months prior to echocardiographic diagnosis of PICM was analysed. PICM was defined as (1) a deterioration in left ventricular (LV) ejection fraction (EF) of &amp;gt;10%, (2) to an EF of &amp;lt;45%, (3) with right ventricular (RV) pacing &amp;gt;20% and (4) the exclusion of alternative causes. Three types of ML models were generated (1) random forest, (2) extreme gradient boosted (XGBoost) (3) K-nearest neighbours algorithm (KNN), with 10-fold cross-validation. Results HM data were available for 12 PICM cases (75 ± 8 years, 72% male). PICM occurred at 2.0 ± 1.2 years. There was no difference between cases and controls in atrial pacing (8±15% vs 18±22% p=0.14), ventricular pacing (81±29% vs 85±24% p=0.62) or base rate (53±5bpm vs 53±5bpm p=0.80). Of the 34 RM features analysed, mean ventricular heart rate was identified as the most important predictor of PICM; area under curve with XG Boost 0.95, KNN 0.95, and random forest 0.86. Other RM features failed to add any more predictive power to the models. Mean ventricular rate was significantly higher in cases than controls (80±6 bpm vs 69±9 bpm p&amp;lt;0.001). Sensitivity analysis was performed to assess whether episodes of atrial fibrillation (AF) were responsible for the higher ventricular rates. After days of AF days were excluded, mean ventricular rate was still significantly higher in cases than controls (79± 6vs 69±9bpm p&amp;lt;0.001) (Figure 1). 10/12 patients had a subsequent CRT upgrade. No consistent pattern emerged in heart rate changes in the first 3 months after CRT upgrade. Conclusion In a group of patients with normal left ventricular function at implant, remotely monitored heart rate can predict early-onset PICM. Further work is required to understand when these heart rate differences emerge, and whether they improve with positive LV remodelling.Table 1.Figure 1.

Implication of geriatric nutritional risk index on treatment response and long-term prognosis in patients with cardiac resynchronization therapy

PurposeGeriatric Nutritional Risk Index (GNRI) is a simple tool for assessing the nutritional status of the aging population. This study aims to explore the clinical implication of GNRI on treatment response and long-term clinical outcomes in heart failure (HF) patients receiving cardiac resynchronization therapy (CRT). MethodsPatients who underwent CRT implantation or upgrade at our hospital were retrospectively included. The association of GNRI and its tertiles with the echocardiographic response, all-cause mortality or heart transplantation, and the first hospitalization due to HF were investigated. ResultsTotally, 647 patients were enrolled, with a median age of 60 [Interquartile Range (IQR): 52–67] years and mean score of GNRI at 107.9 ± 23.7. Super-response rates increased significantly among the GNRI T1, T2, and T3 groups (25.1%, 29.8% vs. 41.1%, P = 0.002). Patients with higher GNRI were more likely to have better LVEF improvement after multiple adjustments (OR = 1.13, 95% CI: 1.04–1.23, P = 0.010). Higher GNRI was independently associated with a lower risk of all-cause mortality or heart implantation (HR = 0.95, 95% CI: 0.93–0.96, P < 0.001) and HF hospitalization (HR = 0.96, 95% CI: 0.95–0.98, P < 0.001). The inclusion of GNRI enhanced the predictability of all-cause mortality based on traditional model, including sex, New York Heart Association functional class, left bundle branch block, QRS reduction, and N-terminal pro-B-type natriuretic peptide level (C statistics improved from 0.785 to 0.813, P = 0.007). ConclusionHigher GNRI was associated with better treatment response and long-term prognosis in HF patients with CRT. Evaluation of nutritional status among CRT population is necessary for individualized choice of potential responders.

Long-Term Outcomes of Cardiac Resynchronization Therapy in Patients With Repaired Tetralogy of Fallot: A Multicenter Study.

A growing number of patients with tetralogy of Fallot develop left ventricular systolic dysfunction and heart failure, in addition to right ventricular dysfunction. Although cardiac resynchronization therapy (CRT) is an established treatment option, the effect of CRT in this population is still not well defined. This study aimed to investigate the early and late efficacy, survival, and safety of CRT in patients with tetralogy of Fallot. Data were analyzed from an observational, retrospective, multicenter cohort, initiated jointly by the Pediatric and Congenital Electrophysiology Society and the International Society of Adult Congenital Heart Disease. Twelve centers contributed baseline and longitudinal data, including vital status, left ventricular ejection fraction (LVEF), QRS duration, and NYHA functional class. Outcomes were analyzed at early (3 months), intermediate (1 year), and late follow-up (≥2 years) after CRT implantation. A total of 44 patients (40.3±19.2 years) with tetralogy of Fallot and CRT were enrolled. Twenty-nine (65.9%) patients had right ventricular pacing before CRT upgrade. The left ventricular ejection fraction improved from 32% [24%-44%] at baseline to 42% [32%-50%] at early follow-up (P<0.001) and remained improved from baseline thereafter (P≤0.002). The QRS duration decreased from 180 [160-205] ms at baseline to 152 [133-182] ms at early follow-up (P<0.001) and remained decreased at intermediate and late follow-up (P≤0.001). Patients with upgraded CRT had consistent improvement in left ventricular ejection fraction and QRS duration at each time point (P≤0.004). Patients had a significantly improved New York Heart Association functional class after CRT implantation at each time point compared with baseline (P≤0.002). The transplant-free survival rates at 3, 5, and 8 years after CRT implantation were 85%, 79%, and 73%. In patients with tetralogy of Fallot treated with CRT consistent improvement in QRS duration, left ventricular ejection fraction, New York Heart Association functional class, and reasonable long-term survival were observed. The findings from this multicenter study support the consideration of CRT in this unique population.

Cardiac resynchronization therapy for pacing induced cardiomyopathy: Role of baseline right ventricular pacing burden.

Cardiac resynchronization therapy (CRT) is indicated for patients with heart failure with reduced left ventricular ejection fraction (LVEF) and chronic right ventricular (RV) pacing burden ≥40% (pacing-induced cardiomyopathy, PICM). It is uncertain whether baseline RV pacing burden impacts response to CRT. We conducted a retrospective study of all CRT upgrades for PICM at our hospital from January 2017 to December 2018. Univariate and multivariable-adjusted changes in LVEF, and echocardiographic response (≥10% improvement in LVEF) at 3-12 months post-CRT upgrade were compared in those with RV pacing burden ≥90% versus<90%. We included 75 patients (age 74±11years, 71% male) who underwent CRT upgrade for PICM. The baseline RV pacing burden was ≥90% in 56 patients (median 99% [IQR 98%-99%]), and<90% in 19 patients (median 79% [IQR 73%-87%]). Improvement in LVEF was greater in those with baseline RV pacing burden ≥90%versus<90% (15.7±9.3%vs. 7.5±9.6%, p=.003). Baseline RV pacing burden ≥90% was a strong predictor of an improvement in LVEF ≥10% after CRT upgrade both in univariate and multivariate-adjusted models (p=.005 and .02, respectively). A higher baseline RV pacing burden predicts a greater improvement in LVEF after CRT upgrade for PICM.

The Year in Hungarian Cardiology 2023: Heart failure

The year 2023 proved to be a productive period with many remarkable scientific papers published from Hungary in the field of heart failure (HF). Our aim with this brief review is to highlight the results of the most prominent landmark randomized clinical trials as well as other relevant influential publications with significant contribution from Hungarian authors. Several clinical trials were published in 2023 with the primary focus on optimizing medical management. Papers described the use of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in HF in association with renal dysfunction, COVID-19 infection, and evaluating their economic impact. A comprehensive manuscript analysed the geographic differences in patient characteristics, treatments, and outcomes in the PARADISE-MI trial population. With regards to glucagon-like peptide-1 (GLP-1) receptor agonists, the STEP-HFpEF landmark clinical trial reported a favourable effect for semaglutide in patients with HFpEF and obesity. The intermittent administration of levosimendan did not improve post-hospitalization clinical stability in a population with advanced HF. In the field of cardiac resynchronization therapy (CRT), results of the BUDAPEST-CRT Upgrade trial was published in the European Heart Journal. This was the first prospective, randomized controlled trial to demonstrate that CRT upgrade in patients with intermittent or permanent RV pacing and HFrEF reduces morbidity and mortality. Several papers focused on the greater field of cardiomyopathies, including medical therapies, diuretic use, and cardiotoxicity. Finally, it is important to mention that an issue of Cardiologia Hungarica was published that was entirely dedicated to HF.

Phenogrouping and risk stratification of patients undergoing cardiac resynchronization therapy upgrade using topological data analysis

Choosing the optimal device during cardiac resynchronization therapy (CRT) upgrade can be challenging. Therefore, we sought to provide a solution for identifying patients in whom upgrading to a CRT-defibrillator (CRT-D) is associated with better long-term survival than upgrading to a CRT-pacemaker (CRT-P). To this end, we first applied topological data analysis to create a patient similarity network using 16 clinical features of 326 patients without prior ventricular arrhythmias who underwent CRT upgrade. Then, in the generated circular network, we delineated three phenogroups exhibiting significant differences in clinical characteristics and risk of all-cause mortality. Importantly, only in the high-risk phenogroup was upgrading to a CRT-D associated with better survival than upgrading to a CRT-P (hazard ratio: 0.454 (0.228–0.907), p = 0.025). Finally, we assigned each patient to one of the three phenogroups based on their location in the network and used this labeled data to train multi-class classifiers to enable the risk stratification of new patients. During internal validation, an ensemble of 5 multi-layer perceptrons exhibited the best performance with a balanced accuracy of 0.898 (0.854–0.942) and a micro-averaged area under the receiver operating characteristic curve of 0.983 (0.980–0.986). To allow further validation, we made the proposed model publicly available (https://github.com/tokmarton/crt-upgrade-risk-stratification).

Comparison of de novo implantation vs. upgrade cardiac resynchronisation therapy: a multicentre experience

Background The clinical safety and consequences of upgrade procedures compared with de novo cardiac resynchronisation therapy (CRT) implantation in heart failure remain unclear. The present study aimed to assess clinical and procedural consequences of patients undergoing CRT upgrade as compared to de novo CRT implantations. Methods In this prospective cohort study, two subgroups were considered as the study population as (1) de novo group that CRT was considered on optimised medical treatment with heart failure of NYHA functional class from II to IV, left ventricular ejection fraction (LVEF) of ≤35%, and QRS width of >130 ms and (2) upgrade group including the patients with previously implantable cardioverter defibrillator (ICD) with the indications for upgrading to CRT. The two groups were compared regarding the changes in clinical outcome and echocardiography parameters. Results The procedure was successful in 95.9% of patients who underwent CRT upgrade and 100% of those who underwent de novo CRT implantation. It showed a significant improvement in LVEF, severity of mitral regurgitation and NYHA functional classification, without any difference between the two study groups. Overall procedural related complications were reported in 10.8% and 3.8% (p = .093) and cardiac death in 5.4% and 2.5% (p = .360), respectively, with no overall difference in postoperative outcome between the two groups. Conclusions Upgrading to CRT is a safe and effective procedure regarding improvement of functional class, left ventricular function status and post-procedural outcome.

Long-term outcomes from upgrade to cardiac resynchronisation therapy in ischaemic versus non-ischaemic heart disease

Background Cardiac resynchronisation therapy (CRT) can be necessary in patients with chronic heart failure, who have already been provided with transvenous cardiac implantable electrical devices. Upgrade procedures revealed controversial results, while long-term outcomes regarding underlying Ischaemic- (ICM) or Non-Ischaemic heart disease (NICM) have yet to be described. Methods The Mannheim Cardiac Resynchronisation Therapy Registry (MARACANA) was designed as a retrospective observational single-centre registry, including all CRT implantations from 2013-2021 (n = 459). CRT upgrades (n = 136) were retrospectively grouped to either ICM (n = 84) or NICM (n = 52) and compared for New York Heart Association classification (NYHA), paced QRS-width, left ventricular ejection fraction (LVEF), tricuspid annular plane systolic excursion (TAPSE) and other heart failure modification aspects in the long-term (59.3 ± 5 months). Results Baseline-characteristics including paced QRS-width, upgrade indications or NYHA-classification were comparable for both groups (group comparison p>.05). The CRT upgrade improved NYHA (ICM: 2.98 ± 0.4 to 2.29 ± 0.7, NICM: 2.94 ± 0.5 to 2.08 ± 0.5) and the LVEF (ICM: 27.2 ± 6.6 to 38.25 ± 8.8, NICM: 30.2 ± 9.4 to 38.7 ± 13.8%) after five years, irrespective of underlying heart disease (each group p < .05, group comparison p>.05). Only ICM revealed significant improvements in TAPSE (15.9 ± 4.1 to 18.9 ± 4.1 mm) and narrowing of the paced QRS-width (185.4 ± 29 to 147.2 ± 16.3 ms) after five years (each p < .05). Conclusions Upgrade to CRT might improve heart failure symptoms and left-ventricular systolic function in the long-term, irrespective of underlying ischaemic or non-ischaemic heart disease.

Cardiac Magnetic Resonance, Electromechanical Activation, Kidney Function, and Natriuretic Peptides in Cardiac Resynchronization Therapy Upgrades.

As the mechanism for worse prognosis after cardiac resynchronization therapy (CRT) upgrades in heart failure patients with RVP dependence (RVP-HF) has clinical implications for patient selection and CRT implementation approaches, this study's objective was to evaluate prognostic implications of cardiac magnetic resonance (CMR) findings and clinical factors in 102 HF patients (23.5% female, median age 66.5 years old, median follow-up 4.8 years) with and without RVP dependence undergoing upgrade and de novo CRT implants. Compared with other CRT groups, RVP-HF patients had decreased survival (p = 0.02), more anterior late-activated LV pacing sites (p = 0.002) by CMR, more atrial fibrillation (p = 0.0006), and higher creatinine (0.002). CMR activation timing at the LV pacing site predicted post-CRT LV functional improvement (p < 0.05), and mechanical activation onset < 34 ms by CMR at the LVP site was associated with decreased post-CRT survival in a model with higher pre-CRT creatinine and B-type natriuretic peptide (AUC 0.89; p < 0.0001); however, only the higher pre-CRT creatinine partially mediated (37%) the decreased survival in RVP-HF patients. In conclusion, RVP-HF had a distinct CMR phenotype, which has important implications for the selection of LV pacing sites in CRT upgrades, and only chronic kidney disease mediated the decreased survival after CRT in RVP-HF.

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.

Pacing-Induced Cardiomyopathy in Leadless and Traditional Pacemakers: A Single-Center Retrospective Analysis.

Pacing-induced cardiomyopathy (PICM) is a clinical syndrome that is characterized by a drop in the left ventricular ejection fraction (LVEF) due to chronic high-burden right ventricular (RV) pacing. It has been postulated that leadless pacemakers (LPs) cause decreased risk of PICM compared to transvenous pacemakers (TVPs), but the exact risk reduction is unknown. We performed a single-center retrospective analysis of adults who received an LP or TVP between January 1, 2014, and April 1, 2022, and had echocardiograms before and after the pacemaker implant. This study's outcomes were the RV pacing percentage, change in EF, the need for cardiac resynchronization therapy (CRT) upgrade, and follow-up duration. A Wilcoxon rank-sum test calculated the change in EF. RV time, defined as the duration from pacemaker placement to the follow-up echocardiogram in months multiplied by the RV pacing percentage, served as a surrogate for how long the RV was paced. A total of 614 patients were screened, and 198 patients were included in the study, where 72 received LP and 126 received TVP. The median follow-up was 480 days. The average of the reported RV percentage pacing was 63.43% for LP and 71.30% for TVP (p=0.14). The incidence of PICM and CRT upgrade was 44% and 9.7%in the LP group and37% and 9.5%in the TVP group(p=0.3 and p>0.9), respectively. After accounting for age, sex, LP versus TVP, atrioventricular nodal ablation, RV pacing percentage, and follow-up duration, univariate analysis showed that RV time was significantly different between the two types of pacemakers (13.54 ± 14.21 months (LP) versus 9.26 ± 13.95 months (TVP), p=0.009). The difference in RV time between patients who underwent CRT upgrade and those who did not was statistically insignificant (12.11 ± 14.47 months (no CRT) versus 9.19 ± 12.00 months (CRT), p=0.5). This analysis demonstrated that the incidence of PICM was high in both groups (44% (LP) versus 37% (TVP)), despite significantly more RV time in patients with LP. There was no difference in CRT upgrade between LP and TVP.

PO-05-027 INCIDENCE OF PACING-INDUCED CARDIOMYOPATHY AND NEED FOR CARDIAC RESYNCHRONIZATION THERAPY UPGRADE IN PATIENTS WITH LEADLESS PACEMAKER: LONG TERM FOLLOW-UP OF 75 PATIENTS

Excessive right ventricular (RV) pacing with traditional pacemaker has been associated with a 17-25% risk of pacing-induced cardiomyopathy (PICM), defined as a decrease of left ventricular ejection fraction by 10% or more. The risk of PICM with more septally placed leadless pacemaker is unknown. We aimed to report the incidence of PICM in patients with leadless pacemaker and the need for cardiac resynchronization therapy (CRT) upgrade. We performed a single-center analysis of patients who underwent leadless pacemaker implantation between January 1, 2014 and April 1, 2022. Patient echocardiogram result pre and post implantation were collected. The outcomes of this study included the incidence of PICM in leadless pacemaker implant patient, the rate of CRT upgrade, RV pacing percentage, total RV pacing time and follow up duration. The definition of total RV pacing time was the duration from pacemaker to last follow up multiplied by RV pacing percentage. A total 75 patients underwent leadless-pacemaker implantation were included in this study. The mean age was 80 ± 8.5 year-old. Indications for single chamber leadless implantation include sick sinus syndrome and bradycardia. Mean duration of follow up was 14.6 months. The RV pacing percentage was 64.4 ± 38.58 %.The mean RV pacing time was 9.2 ± 1.4 months, PICM was found in 32 patients (44%), 10 patients (13.5%) required CRT upgrade due to congestive heart failure symptoms. The mean duration between implantation of leadless pacemaker to upgrade CRT was 372 ± 489.8 days. The incidence of PICM in leadless pacemaker patients was 44% and 13.5 % of patients required CRT upgrade within 2 years after the leadless pacemaker implant in the majority of the patients. Further studies are necessary to confirm these findings.

The therapeutic benefit of upgrade to cardiac resynchronization therapy in patients with pacing-induced cardiomyopathy.

Pacing-induced cardiomyopathy (PICM) is an important cause of heart failure in patients with a right ventricular pacing burden. Recent evidence suggests that an upgrade to cardiac resynchronization therapy (CRT) may confer benefit in PICM. To assess the extent and identify predictors of improvement following upgrade to CRT in patients with PICM. We retrospectively analyzed 43 patients undergoing CRT upgrade for PICM over the 10-year period of 2011 to 2021 at our center. All patients with PICM who underwent device upgrade from a dual- or single-chamber ventricular pacemaker to CRT were included. PICM was defined as a decrease of ≥10% in left ventricular ejection fraction (LVEF), resulting in an LVEF <50% among patients with ≥20% Right ventricular pacing burden without an alternative cause for cardiomyopathy. LVEF significantly improved from 28.7% preupgrade to 44.3% post-CRT upgrade (P < .01). Of 37 patients with severe LV dysfunction, 34 (91.9%) improved to an LVEF >35% and 13 (35.1%) improved to an LVEF >50%. The LV end-diastolic diameter decreased from 5.9 cm preupgrade to 5.4 cm postupgrade (P < .01). Using linear regression, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use was associated with significant LVEF improvement (+7.21%, P = .05). We observed a low rate of complications, and 1 in 4 CRT upgrades required venoplasty (n = 10 of 43, 23.3%). We provide further evidence for the benefit of CRT upgrade in the management of patients with PICM.

Efficacy of CRT upgrade in pacemaker-induced cardiomyopathy in an outpatient clinic – Results of a prospective registry

PurposeThe aim of this prospective, monocentric registry study was to investigate whether upgrading to cardiac resynchronization therapy (CRT) in pacemaker-induced cardiomyopathy (PICM) can improve left ventricular function in typical outpatient clinical patients. MethodsWe screened for PICM in a pacemaker outpatient clinic between 2017 and 2021. The follow-up period was 6 months. The primary endpoint was decreased left ventricular end systolic volume (LVESV), and the responder criterion was decreased LVESV >15%. Secondary endpoints were LVEF, NYHA class, device-associated complications and death. Results66 patients were newly diagnosed with PICM. 55 of them received a CRT upgrade. For the primary endpoint, LVESV decreased from 101.6 ± 48.2 ml to 75.9 ± 35.8 ml (p < 0.001). Secondary endpoints were: a) LVEF increased from 31.5 ± 5.4% to 46.1 ± 7.6% (p < 0.001) and b) NYHA class improved by an average of one class in both groups (p < 0.001). The overall complication rate was 1.8%. ConclusionsCRT upgrade in outpatient clinic patients with PICM improves left ventricular function and functional capacity and is associated with an acceptable complication rate.

Abstract 10991: Incidence of Pacing-Induced Cardiomyopathy in Leadless and Traditional Pacemakers: A Retrospective Analysis of 198 Patients

Introduction: Transvenous pacemaker (TVP) with right ventricular (RV) apical pacing over 40% has been associated with a 17-25% risk of Pacing-Induced Cardiomyopathy (PICM), defined as a decrease in ejection fraction (EF) by 10% or more. It’s been postulated that a septally placed Leadless Pacemaker (LP) causes less risk of PICM, but the exact incidence is unknown. Methods: We performed a single-center retrospective analysis of adults who received an LP or TVP between January 1, 2014 and April 1, 2022 and had echocardiograms before and after the pacemaker. This study’s outcomes were the RV pacing percentage, change in EF, the need for cardiac resynchronization therapy (CRT) upgrade, and follow-up duration. A Wilcoxon rank-sum test calculated the change in EF. RV time, defined as the duration from pacemaker to echocardiogram in months multiplied by the RV pacing percentage, served as a surrogate for how long the RV was paced. Results: A total of 614 patients were screened and 198 patients were included in the study, where 72 received LP and 126 received TVP. The median follow-up was 480 days. The average of the reported 161 patients with RV percentage pacing for LP was 63.43% and TVP was 71.30% (p=0.14). The incidence of PICM and CRT upgrade in the LP group was 44% and 9.7% in LP and TVP was 37% and 9.5% in TVP (p=0.3 and p&gt;0.9), respectively. After accounting for age, age, sex, LP vs TVP, atrioventricular nodal ablation, RV pacing percentage, and follow-up duration, univariate analysis showed that RV time was significantly different between pacemakers (LP 1,353.97 ± 1,420.56 months vs TVP 926.47 ± 1,395.17 months, p=0.009), but not with CRT (No CRT 1,211.37 ± 1,447.45 months vs CRT 919.34 ± 1,199.54 months, p=0.5). Conclusions: This analysis demonstrated that the incidence of PICM was high in both groups (LP 44% vs TVP 37%). Despite significantly more RV time in patients with LP, there was no difference in CRT upgrade.