Cardiac Resynchronization Therapy Therapy Research Articles

The Year in Hungarian Cardiology 2023: Arrhythmias

In 2023, Hungary produced notable scientific publications focused on cardiac arrhythmias. This review highlights the most impactful papers, authored at least in part by Hungarians, featuring work conducted at Hungarian research sites and published in international peer-reviewed journals. We give a short overview regarding papers dealing with the role of imaging (different types of ultrasound, cardiac magnetic resonance imaging and electroanatomical mapping) in treating cardiac arrhythmias. We summarize the novelties of ischemic complications of atrial fibrillation (AF), cerebral safety of AF ablation, and current AF ablation techniques. Optimizing risk stratification of ventricular tachycardia (VT) ablation was a landmark paper of our “machine learning” research. Further studies have made significant strides in cardiac device therapy, notably through the groundbreaking BUDAPEST-CRT Upgrade Trial for heart failure, which demonstrated marked reductions in deaths and hospitalizations following Cardiac Resynchronization Therapy (CRT) upgrade procedures. Research on the impact of frailty on CRT outcomes has underscored the importance of tailored treatments. Artificial intelligence, particularly topological data analysis, has been crucial in personalizing CRT therapy. Additionally, advancements in remote monitoring and lead extraction techniques have mirrored the rapid evolution of cardiac technology and care.

Does scar burden predict sudden cardiac death in patients with cardiac resynchronization therapy? - A Systematic Review and Meta-Analysis

Abstract Background Based on latest guidelines, scar burden assessment may have a crucial role in appropriate device choice in cardiac resynchronization therapy (CRT), but no randomized controlled trials have been made yet.1 Scar burden is associated with a higher prevalence of ventricular arrhythmias (VA) and sudden cardiac death (SCD).2 Late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) can accurately evaluate the extent of myocardial scar.3. Purpose Our aim is to investigate the association between scar burden and SCD risk in cardiac resynchronization therapy patients. Methods We performed a systematic literature search on MEDLINE using the PubMed, Embase, Scopus, and CENTRAL databases. Heart failure patients with reduced ejection fraction and CRT therapy were collected. The primary endpoint was sudden cardiac death events. Meta-analyses were performed using the META and DMETAR packages in R, using a random-effects model. The risk of bias was assessed using Quips tool and the quality of evidence was evaluated using the GRADE assessment. Results 18 eligible articles have been included in our study, with a total of 2917 patients, of whom 830, 1324, and 391 have been implanted with an ICD, CRT-D, CRT-P respectively. Altogether 59,05 % of the total population were LGE-CMR positive. The average proportion of appropriate ICD shock was 15,65 % per the total population during the median follow-up time of 39,45 months. Based on the univariant analysis of 14 articles, the cumulative hazard ratio of developing sudden cardiac death events, in the scar burden positive population compared to scar burden negative was 1,95 with CI: 1,29- 2,96 p<0,001. The multivariant analysis shows the HR of 1,88 with CI: 1,20- 2,93 p<0,001. There were 4 articles using the competing risk model which is considered to be the highest evidence level. Based on that analysis we found only a trend with a HR of 1,55 CI: 0,75-2,92. Calculating from the event numbers based on 8 eligible articles, the high scar burden group had 5.55 higher odds of getting SCD events. (OR: 5.55. CI 2,52-12,22 p<0,001). Conclusion In our meta-analysis, LGE-CMR was associated with a trend toward appropriate device therapy and can identify a subgroup of patients with an increased risk of life-threatening VA. Based on our results performing an MRI before device implantation might be important to select high-risk patients for SCD.Forest plot O.R.Forest plot uni. H.R.

Abstract 14398: Predictors of Major Adverse Cardiac Events in Individuals With Left Bundle Branch Block and Cardiac Resynchronization Therapy: Analysis From the Derivate Registry

Background: Cardiac resynchronization therapy (CRT) plays an important role in managing patients with advanced heart failure (HF) with reduced ejection fraction and interventricular conduction block, as it reestablishes synchrony and cardiac function while reducing the risks of HF-related hospitalizations and mortality. Despite the well-described advantages of CRT, approximately 30% to 40% of patients fail to respond to therapy. Therefore, our study aimed to define patient characteristics associated with major adverse cardiac events (MACE) in individuals with left bundle branch block (LBBB) who received CRT. Methods: The study cohort included patients enrolled in the CarDiac MagnEtic Resonance for Primary Prevention Implantable CardioVerter DefibrillAtor ThErapy (DERIVATE) registry who had LBBB and had previously undergone CRT. We defined MACE as a composite outcome including cardiac death, hospitalization for heart failure, or major adverse arhythmic events. Cox regression analysis was used to examine the relationship between MACE and CRT therapy. Kaplan-Meier curves were utilized to explore the association between CRT and cardiac death. Results: Out of 300 individuals, 144 (48%) experienced MACE. The cohort had a mean age of 63.9 ± 10.9, with 29% being male. The median follow-up period was 1285 days. Ischemic cardiomyopathy was identified as an independent predictor of MACE (HR = 3.54; 95% CI [2.31-5.41]; P<0.01) and cardiac death (HR = 24.10; 95% CI [10.71-54.21]; P<0.01) in patients with LBBB and CRT. Amiodarone therapy was associated with a 1.91-fold (95% CI [1.20-3.05]; P=0.01) increased risk of MACE. Notably, multivariate analysis did not reveal a significant association between gender, hypertension, renal function, diabetes mellitus, or NYHA class III/IV and the occurrence of MACE. Conclusion: Our findings suggest that ischemic cardiomyopathy and the use of amiodarone therapy are independent predictors of MACE in patients with LBBB who previously underwent CRT. These findings suggest that patient-level characteristics are important predictors of MACE; however, further research is needed to better understand the interplay between ejection fraction, conduction disease, and patient characteristics post-CRT therapy.

CRT non-responder to responder conversion rate in the MORE-CRT MPP Trial.

To assess the impact of MultiPoint™ Pacing (MPP) in cardiac resynchronization therapy (CRT) non-responders after six months of standard biventricular pacing (BiVP). The trial enrolled 5,850 patients who planned to receive a CRT device. The echocardiography core laboratory assessed CRT response before implant and after six months of BiVP; non-response to BiVP was defined as < 15% relative reduction in left ventricular end-systolic volume (LVESV). Echocardiographic non-responders were randomized in a 1:1 ratio to receive MPP (541 patients) or continued BiVP (570 patients) for an additional six months and evaluated the conversion rate to the echocardiographic response. The characteristics of both groups at randomization were comparable. The percentage of non-responder patients who became responders to CRT therapy was 29.4% in the MPP arm and 30.4% in the BIVP arm (p=0.743). In patients with > 30 mm spacing between the two left ventricular pacing sites (MPP-AS), identified during the first phase as a potential beneficial subgroup, no significant difference in the conversion rate was observed. Our trial shows that approximately 30% of patients, who do not respond to CRT in the first six months, experience significant reverse remodeling in the following six months. This finding suggests that CRT benefit may be delayed or slowly incremental in a relevant proportion of patients and that the percentage of CRT responders may be higher than what has been described in short/middle-term studies. MPP does not improve CRT response in non-responders to BiVP, even with MPP-AS.

Conduction System Pacing Upgrade in Chronic Heart Failure with Severe Left Ventricular Dysfunction and Chronic Atrial Fibrillation.

Cardiac resynchronization therapy (CRT) is a standard treatment for patients with severe congestive heart failure. However, one-third of patients receiving CRT are non-responders. Conduction system pacing (CSP), including His-bundle pacing (HBP) and left bundle branch area pacing (LBBAP), has become an alternative to CRT therapy. Furthermore, CRT therapy with CSP has shown to be more effective than CRT alone. When an implantable cardiac defibrillator or CRT-defibrillator is implanted with CSP, the problem of which port the HBP lead and LBBAP lead should be connected to arises. We report 2 cases of upgrading to CRT with CSP by utilizing the atrial ports for HBP and LBBAP leads. The procedure is a simple, reasonable, and effective therapy for end-stage heart failure.

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.

Update in LV Only Fusion CRT Pacing: Annals and Future Perspectives.

Triple-chamber cardiac devices are utilized for cardiac resynchronization therapy (CRT) and is the standard-of-care therapy for heart failure (HF) patients in the current guidelines. In the setting of biventricular (BIV) pacing it involves a mandatory implantation of right ventricular (RV) lead that allows simultaneous BIV pacing with 0 ms VV (ventricular to ventricular) interval. Nevertheless, it seems that response to CRT is not related to RV lead position. RV pacing is known for deleterious effects on RV/Left Ventricle (LV) function and should not be used in persons with normal atrioventricular conduction (AV) and sinus rhythm. As it compensates for the additional asynchrony induced by unnecessary stimulation of RV pacing, only pacing the left ventricle (LV) may result in improved cardiac resynchronization therapy (CRT) outcomes and a decrease in the number of individuals who do not respond to the procedure. Furthermore, leadless LV fusion CRT pacing without RV lead could be a potential CRT therapy alternative to BIV pacing in nonischemic heart failure patients with preserved AV conduction. The aim of our study is to made an update in cardiac resynchronization therapy with LV only fusion pacing.

Computed Tomography Cardiac Veins Evaluation in Congenital Transposition of Great Vessels Prior to Cardiac Resynchronization Therapy (Crt)

Adult patients with transposition of great vessels are often candidates for cardiac resynchronization therapy (CRT). Cardiac vein anatomy is of crucial importance in planning optimal CRT therapy. Cardiac veins are very variable. In congenitally corrected transposition of great vessels coronary arteries have an unusual course but coronary veins although much less studied have much more varieties. In such cases cardiac computed tomography (CT) might offer important information prior to electrophysiological procedures. The objective of this study is to present a series of patients with transposition of the great arteries (TGA) both congenitally corrected TGA and D TGA in which imaging was used to help planning placement of leads for CRT. CT findings are thoroughly described as well as the consequent interventional procedure.

Myocardial Perfusion SPECT Imaging Radiomic Features and Machine Learning Algorithms for Cardiac Contractile Pattern Recognition

A U-shaped contraction pattern was shown to be associated with a better Cardiac resynchronization therapy (CRT) response. The main goal of this study is to automatically recognize left ventricular contractile patterns using machine learning algorithms trained on conventional quantitative features (ConQuaFea) and radiomic features extracted from Gated single-photon emission computed tomography myocardial perfusion imaging (GSPECT MPI). Among 98 patients with standard resting GSPECT MPI included in this study, 29 received CRT therapy and 69 did not (also had CRT inclusion criteria but did not receive treatment yet at the time of data collection, or refused treatment). A total of 69 non-CRT patients were employed for training, and the 29 were employed for testing. The models were built utilizing features from three distinct feature sets (ConQuaFea, radiomics, and ConQuaFea + radiomics (combined)), which were chosen using Recursive feature elimination (RFE) feature selection (FS), and then trained using seven different machine learning (ML) classifiers. In addition, CRT outcome prediction was assessed by different treatment inclusion criteria as the study’s final phase. The MLP classifier had the highest performance among ConQuaFea models (AUC, SEN, SPE = 0.80, 0.85, 0.76). RF achieved the best performance in terms of AUC, SEN, and SPE with values of 0.65, 0.62, and 0.68, respectively, among radiomic models. GB and RF approaches achieved the best AUC, SEN, and SPE values of 0.78, 0.92, and 0.63 and 0.74, 0.93, and 0.56, respectively, among the combined models. A promising outcome was obtained when using radiomic and ConQuaFea from GSPECT MPI to detect left ventricular contractile patterns by machine learning.

Strategy for Failed Transvenous Left-Ventricular Lead Placement in Cardiac Resynchronization Therapy: Surrender or Struggle?

Introduction: For those cardiac resynchronization therapy (CRT) candidates who experience left-ventricular (LV) lead placement failure or underwent concomitant cardiac surgeries, surgical placement of epicardial LV lead guided by electroanatomic mapping may be a promising alternative. Methods: Electroanatomic mapping was used to guide positioning of the LV lead through a surgical approach. The LV lead was placed at the region with the latest local LV activation and normal voltage, away from the scar. Results: From April 2010 to September 2018, 10 consecutive patients (3 female) underwent surgical epicardial LV lead implantation. Among them, 3 had other surgical indications simultaneously (including 1 CRT non-responder), and 7 had failed transvenous LV lead placement. After CRT, the QRS duration was shortened from 149.3 ± 20.4 ms to 125.1 ± 15.2 ms (p = 0.01). At 6 months, the LV ejection fraction was significantly improved and remained stable in the follow-up (FU) period thereafter (baseline vs. 6 months, 31.0 ± 8.3% vs. 42.2 ± 13.4%, p = 0.006). Other parameters, including the threshold and impedance of the LV lead, were also stable at a mean FU of 755 ± 406 days, and the NYHA functional classification decreased from 2.9 ± 0.7 to 1.8 ± 0.8 (p = 0.002). Conclusions: Placement of an epicardial LV lead guided by electroanatomic mapping could be used as an adjunctive strategy in patients who were unable or refractory to conventional CRT therapy. This approach could also be applied in patients who had other surgical indications at the same time.

Abstract 12159: Impact of Ischemic Heart Disease on Cardiac Resynchronization Therapy - Analysis From National Inpatient Sample

Introduction: Comparative outcomes of hospitalizations for Cardiac Resynchronization Therapy (CRT) implantation procedures with and without coexisting Ischemic Heart Diseases (IHD) have not been studied at national level databases. We attempted to assess outcomes and baseline characteristics in these hospitalizations based on the National Inpatient Sample (NIS). Hypothesis: Ischemic heart disease worsens inpatient outcomes in patients undergoing CRT implantation. Methods: We conducted a retrospective analysis of hospitalizations for CRT implantation from the National Inpatient Sample (NIS) between 2013 and 2014. ICD-9 Billing codes were used to identify the target population. The primary outcomes were inpatient mortality, and hospital length and cost of stay. Results: A total of 11057 cases were identified. IHD was listed as any diagnosis in 66% of these hospitalizations. The mean age was 72.5 and 66.9 years for CRT implantation with and without IHD, respectively. Hospitalizations without IHD were more likely to be female (44% vs. 25%; p=0.01). Patients in the CRT with IHD group had a higher comorbidity burden with a higher proportion of hypertension, chronic kidney disease, anemia, peripheral artery disease, and congestive heart failure (Table 1). Inpatient mortality was similar between both groups (OR 1.17, CI 0.75-1.81). The IHD cohort had higher rates of cardiac arrest (OR 1.30, CI 1.05-1.62), acute kidney injury (OR 1.21, CI 1.08-1.35), longer length and a higher cost of stay (Table 1). Conclusions: IHD is associated with higher costs, longer length of stay, and higher rates of cardiac arrest. However, the in-hospital mortality was not different between the two groups. Higher incidence of cardiac arrest in patients with CRT and IHD underlines the importance of ICD with CRT. The clinical implication is that the threshold of selecting a CRT-D device in patients eligible for CRT therapy should be lower in patients with IHD vis-à-vis patients without IHD.

Cardiac mechanics as predictors of left ventricular reverse remodelling in patients with dilated non-ischemic cardiomyopathy

Abstract Background and purpose The appearance of left ventricular reverse remodelling (LVRR) is associated with a better prognosis in patients with dilated non-ischemic cardiomyopathy (DCM). Our aim was to identify cardiac imaging parameters, including speckle tracking by transthoracic echocardiography (TTE) and feature tracking by CMR, associated with LVRR in a prospective cohort of patients with DCM. Methods From 2014 to 2021, 182 patients with DCM and left ventricle ejection fraction (LVEF) &amp;lt;40% were prospectively evaluated in our hospital. LVRR was defined as an increase in LVEF ≥10 points or absolute LVEF ≥50%, associated with a reduction in left ventricular end- diastolic diameter ≥10%. Patients underwent multimodality imaging evaluation including CMR with a 1.5 Tesla scanner, and TTE. Cardiac mechanics, including global longitudinal strain (GLS), strain rate (SR) and mechanical dispersion (MD) were measured. Results Median age of our cohort was 62.3 (14.4) years, and 67.7% were male. Most patients (&amp;gt;90%) were treated with beta-blockers or RASS blockers, and 67% with mineralocorticoid receptor antagonists. 30% had cardiac resynchronization therapy (CRT) and 37% had ICD as primary prevention. Mean LVEF was 31.3%. During a mean follow-up period of 35.9 (35.4) months, 38.3% of patients had LVRR. Age and gender distribution were similar in both groups. Regarding cardiovascular risk factors and pharmacological treatment, no differences were found between patients with and without LVRR. Baseline CRT therapy was not associated with LVRR (22.6% vs 34.7%; p=0.249). However, there was a trend towards higher LVRR in those who received CRT during follow-up 18.8% vs 0%; p=0.069). Patients who experienced LVRR had lower basal LVEF (23.4% vs 29%; p&amp;lt;0.008), as well as poorer RV function, including lower RVEF (40.5% vs 51%; p=0.006) and lower TAPSE (16 mm vs 19 mm; p=0.021). Regarding cardiac mechanics, those patients with lower GLS (−9% vs −12%; p=0.001), and higher MD (73 mm vs 55 mm; p=0,050) had LVRR more frequently during follow-up. The presence of a left bundle branch block (LBBB) contraction pattern by strain was associated with higher rate of LVRR (83.3% vs 30.4%; p=0.011). The burden of fibrosis measured by LGE with CMR was not associated with LVRR (14% vs 12%; p=NS). Patients with LVRR had a lower cardiovascular mortality (3.3 vs 14.3%; p=0.117), lower mortality due to heart failure (0% vs 12.2%; p=0.046), less heart failure hospitalizations (20% vs 46.9%; p=0.016), and a lower incidence of ventricular tachyarrhythmias (3.3% vs 18.4%; p=0.051). Conclusions LVRR in patients with DCM receiving optimized medical therapy is associated with a better prognosis. Imaging parameters, including a lower basal LVEF, RVEF, GLS and higher MD, as well as LBBB echo pattern, were associated with a higher frequency of LVRR, and might help to identify patients who could benefit from CRT/and may be helpful to stratify patients's risk. Funding Acknowledgement Type of funding sources: None.

Atrial fibrillation associated with heart failure treated by a 2-lead CRT-DX system (BIO-AffectDX): Study design and clinical protocol.

BackgroundEvidence to support use of cardiac resynchronization therapy (CRT) among patients with both heart failure (HF) and atrial fibrillation (AF) is largely limited to retrospective or post hoc subanalyses. Data from a prospectively enrolled and contemporary cohort are needed.ObjectiveWe aim to better characterize the changes from baseline in HF patients with concomitant AF subsequently implanted with a 2-lead CRT-DX system capable of sensing in the atrium, aggregating diagnostics, and delivering CRT therapy. The primary objective of this study is to evaluate the percentage of all HF subjects with an improvement in a clinical composite score from pre-CRT implant to 12 months.MethodsThe study is a US-based, prospective, observational multicenter clinical trial conducted at up to 50 sites and enrolling approximately 400 subjects with a follow-up period of 1 year. Multiple subject assessments, atrial rhythm status, and device interrogation will be collected at follow-up visits occurring at 3, 6, and 12 months postimplant.ResultsA Clinical Events Committee will adjudicate subject HF events, arrhythmia events, death events, and all device-classified ventricular tachycardia and ventricular fibrillation episodes with treatment that are collected throughout the follow-up period. Their decisions are based on independent physician review of the data from sites and device interrogation.ConclusionThe BIO-AffectDX study aims to provide further insight into the expected outcomes from CRT treatment in patients with HF and AF.

State-of-the-art narrative review: multimodality imaging in electrophysiology and cardiac device therapies.

Cardiac electrophysiology procedures have evolved to provide improvement in morbidity and mortality for many patients. Cardiac resynchronization therapy (CRT), implantable cardioverter/defibrillator (ICD) placement and lead extraction procedures are proven procedures, associated with significant reductions in patient morbidity and mortality as well as improved quality of life. The applications and optimization of these therapies are an evolving field. The optimal use and outcomes of cardiac electrophysiology procedures require a multidisciplinary approach to patient selection, device selection, and procedural planning. Cardiac imaging using echocardiography plays a key role in selection of patients for CRT therapy, for guidance of left ventricular (LV) lead placement, and for optimization of atrioventricular pacing delays in patients with CRT. Cardiac computed tomography (CT) is an important tool in assessment of lead perforation, as well as assessing risk of lead extraction and procedural planning. Cardiac magnetic resonance imaging (MRI) is an important adjunct to transthoracic echocardiography for patient selection and risk stratification for defibrillator therapy for multiple disease states including ischemic cardiomyopathy, hypertrophic cardiomyopathy, cardiac sarcoidosis, and arrhythmogenic right ventricular cardiomyopathy (ARVC). Cardiac positron emission tomography (PET) is a useful adjunct to the diagnosis of device infections as well as inflammatory conditions including cardiac sarcoidosis. Our review attempts to summarize the contemporary roles of multimodality imaging in CRT therapy, ICD therapy and lead extraction therapy.

Global longitudinal strain predicts responders after cardiac resynchronization therapy-a systematic review and meta-analysis.

To evaluate the association between baseline global longitudinal strain (GLS) and ΔGLS (difference of baseline GLS and follow-up) and cardiac resynchronization therapy (CRT) response defined either with clinical or with echocardiographic characteristics.This meta-analysis was performed in accordance to both the Meta-Analysis of Observational Studies in Epidemiology and Strengthening the Reporting of Observational Studies in Epidemiology guidelines. Two independent investigators performed a comprehensive systematic search in MedLine, EMBASE and Cochrane databases through September 2019 without limitations. Data analysis was performed by using the Review Manager software (RevMan), version 5.3, and Stata 13 software. A p value of less than 0.05 (two-tailed) was considered statistically significant.Twelve studies (1004 patients, mean age 63.8years old, males 69.4%) provided data on the association of baseline GLS with the response to CRT therapy. We found that CRT responders had significantly better resting GLS values compared with non-responders [GLS mean difference -2.13 (-3.03, -1.23), p < 0.001, I2 78%]. Furthermore, CRT responders had significantly greater improvement of GLS at follow-up compared with non-responders [ΔGLS mean difference -3.20 (-4.95, -1.45), p < 0.001, I2 66%]. These associations remained significant in a subgroup analysis including only studies with similar CRT response definition. In this meta-analysis, we found that CRT responders had a baseline and ΔGLS significantly higher than the non-responders strengthening the central role of GLS as a tool for selecting candidates for CRT. Furthermore, improved GLS values after CRT may be used to better define CRT responders.

Cardiac resynchronization therapy in paediatric patients with congenital heart disease: single centre with 10 years of experience.

In recent years, cardiac resynchronization therapy (CRT) has also started to be performed in the paediatric and CHD population. This study aimed to evaluate the efficacy of CRT in children with CHD. Patients with CHD who underwent CRT treatment in our paediatric cardiology clinic between January, 2010 and January, 2020 were included in the study. Demographic findings, 12-lead electrocardiograms, echocardiograms, clinical characteristics, management strategies, and outcomes were reviewed systematically. The study population consisted of 18 CHD patients who had been treated with CRT for 10 years in our institution. The median age was 11 years (2.2-18 years) and the median weight was 39 kg (10-81 kg). Systemic ventricle was left ventricle in 13 patients, right ventricle in 4 patients, and 1 patient had single-ventricle physiology. CRT implantation indications were as follows: dysfunction after permanent pacemaker in 11 patients, dysfunction after left bundle branch block in 4 patients, and systemic ventricular dysfunction in 3 patients. CRT implantation techniques were epicardial (n = 13), hybrid (n = 4), and transvenous (n = 1) methods. QRS duration significantly decreased after CRT implantation (160 versus 124 m/second, p < 0.05). Median systemic ventricle ejection fraction (EF) significantly increased after the procedure (30 versus 50%, p < 0.05). Fourteen patients (78%) were responders, two patients (11%) were superresponders, and two patients (11%) were non-responders after the CRT treatment. One patient deceased during follow-up. Median follow-up duration was 40 months (6-117 months). When electromechanical dyssynchrony occurs in paediatric cases with CHD and developing heart failure, patients should be evaluated in terms of CRT to improve ventricular function. Alternative CRT therapy will be beneficial in these cases that do not improve clinically despite optimal medical treatment.

Changes of NT-proBNP and sST2 levels for predicting isolated episodes of ventricular tachyarrhythmias and electrical storm in patients with systolic heart failure and various implanted devices

Aim . To study the changes in N-terminal pro-brain natriuretic peptide (NT-proBNP) and growth stimulation gene-2 (sST2) to predict isolated episodes of ventricular tachyarrhythmias (VTA) and electrical storm (ES) in patients with systolic heart failure and implanted cardioverter-defibrillators, cardiac resynchronization therapy (CRT) defibrillators, as well as cardiac contractility modulation (CCM) devices. Material and methods . The study included 69 patients (mean, 59; women, 10; mean age, 59±13 years) with class I-III systolic HF and ischemic (n=36) or nonischemic (n=33) cardiomyopathy. The survey was carried out at baseline, as well as 1, 3, 6 and 12 months after device implantation. This included data collection, physical examination, determination of NT-proBNP and sST2, 6-minute walk test, electrocardiography (ECG), 24-hour Holter monitoring, echocardiography, assessment of device performance. Predictors of isolated VTA and ES were identified using ROC and multivariate analyzes. Results . According to the follow-up (median, 28 months) results, 3 groups of patients were formed: group 1 — without VTA (n=45); group 2 — isolated VTA (n=15); group 3 — ES (n=9). According to multivariate analysis, predictors of isolated VTA were as follows: 1) baseline NT-proBNP &gt;3200 pg/ml; 2) minimum NTproBNP &gt;1100 pg/ml during 12-month follow-up; 3) sST2 &gt;26 ng/ml 3 months after device implantation; 4) presence of old myocardial infarction; 5) no echocardiographic signs of response to CRT or CCM therapy. There were following predictors of ES: 1) left ventricular end-systolic dimension &gt;7,0 cm; 2) presence of VTA runs according to 24-hour Holter monitoring; 3) no echocardiographic signs of response to CRT or CCM therapy. Conclusion . The results obtained indicate that NT-proBNP and sST2 assessment in patients with systolic heart failure is promising for predicting isolated VTA, but not ES. Cardiac reverse remodeling as a result of effective CRT or CCM therapy is associated with a significant risk reduction for isolated VTA and ES.

Analysis of Risk Factors for Acute Heart Failure in Patients with Dilated Cardiomyopathy and Persistent Severe Functional Mitral Regurgitation Despite Cardiac Resynchronization Therapy

Congestive heart failure resulting from non-ischemic dilated cardiomyopathy (DCM) with secondary functional mitral regurgitation (FMR) is associated with poor prognosis. Medical treatment results in a 1-year survival of 52% to 87% and a 5-year survival of 22% to 54%, with highest survivals observed in more recent years, probably reflecting improvements in medical therapy. Non-surgical interventions involve cardiac resynchronization therapy. In addition to medical treatment, cardiac resynchronization therapy (CRT) should be considered in patients with New York Heart Association (NYHA) class II– IV HF, left ventricular ejection fraction (LVEF) =35%, normal sinus rhythm and left bundle branch block with QRS &gt;150 ms. In these patients, CRT can also facilitate left ventricular (LV) reverse remodeling and reduce associated FMR.&#x0D; The aim of this study was to investigate the features of symptomatology and to analyze the risk factors for acute heart failure (AHF) in patients with DCM and persistent severe functional mitral regurgitation despite CRT and optimal guideline-directed medical therapy (GDMT).&#x0D; Materials and methods. After providing informed consent, 144 patients with severe FMR were involved in the study. Concomitant tricuspid valve regurgitation was registered in 142 (98.6%) cases. The median LVEF was 27.0 (23.0-31.6)%. 40 (27.8%) patients had a permanent form of atrial fibrillation, and 24 (16.7%) patients had a first-degree atrioventricular node block. The median NT-proBNP was 2600 (2133-3200) pg/ml, indicating the presence of severe chronic heart failure.&#x0D; Results. The median term after CRT device implantation was 36 (3.5-60) months. A comparative analysis between DCM patients with and without CRT revealed statistically significant differences between clinical characteristics, namely: age (p=0.020), lower heart rate (p=0.004), lower hemoglobin (p=0.017), higher erythrocyte sedimentation rate (ESR) (p=0.000) and more frequent AHF at the hospital stage (p=0.030). The incidence of AHF at the hospital stage was 13.8% in patients with CRT and 3.5% in those without CRT. The calculated odds ratio of AHF was 4.44 (95% confidence interval (CI) 1.039-18.971), and the relative risk of AHF was 3.966 (95% CI 1.054-14.915).&#x0D; Discussion. FMR has been reported to persist in about 20% to 25% of CRT patients and, in an additional 10% to 15%, it may actually worsen after CRT. In this subset of CRT non-responders, reduced reverse remodeling, increased morbidity, and increased mortality have been reported compared with CRT patients in whom FMR was significantly reduced or abolished.&#x0D; Conclusions. The results of our study demonstrate that severe functional mitral regurgitation despite cardiac resynchronization therapy in patients with dilated cardiomyopathy is a significant risk factor for AHF and subsequent hospitalizations for heart failure.

Electrode Model and Simulation of His- Bundle Pacing for Cardiac Resynchronization Therapy

Abstract A disturbed synchronization of the ventricular contraction can cause a highly developed systolic heart failure in affected patients with reduction of the left ventricular ejection fraction, which can often be explained by a diseased left bundle branch block (LBBB). If medication remains unresponsive, the concerned patients will be treated with a cardiac resynchronization therapy (CRT) system. The aim of this study was to integrate His-bundle pacing into the Offenburg heart rhythm model in order to visualize the electrical pacing field generated by His-Bundle-Pacing. Modelling and electrical field simulation activities were performed with the software CST (Computer Simulation Technology) from Dessault Systèms. CRT with biventricular pacing is to be achieved by an apical right ventricular electrode and an additional left ventricular electrode, which is floated into the coronary vein sinus. The non-responder rate of the CRT therapy is about one third of the CRT patients. His- Bundle-Pacing represents a physiological alternative to conventional cardiac pacing and cardiac resynchronization. An electrode implanted in the His-bundle emits a stronger electrical pacing field than the electrical pacing field of conventional cardiac pacemakers. The pacing of the Hisbundle was performed by the Medtronic Select Secure 3830 electrode with pacing voltage amplitudes of 3 V, 2 V and 1,5 V in combination with a pacing pulse duration of 1 ms. Compared to conventional pacemaker pacing, His-bundle pacing is capable of bridging LBBB conduction disorders in the left ventricle. The His-bundle pacing electrical field is able to spread via the physiological pathway in the right and left ventricles for CRT with a narrow QRS-complex in the surface ECG.

Novel two-lead cardiac resynchronization therapy system provides equivalent CRT responses with less complications than a conventional three-lead system: Results from the QP ExCELs lead registry.

IntroductionThe novel two‐lead cardiac resynchronization therapy (CRT)‐DX system utilizes a floating atrial dipole on the implantable cardioverter‐defibrillator lead, and when implanted with a left ventricular (LV) lead, offers a two‐lead CRT system with AV synchrony. This study compared complication rates and CRT response among subjects implanted with a two‐lead CRT‐DX system to those subjects implanted with a standard three‐lead CRT‐D system.Methods and ResultsA total of 240 subjects from the Sentus QP—Extended CRT Evaluation with Quadripolar Left Ventricular Leads postapproval study were selected to identify 120 matched pairs based on similar demographic characteristics using a Greedy algorithm. The complication‐free rate was evaluated as the primary endpoint. All‐cause mortality, heart failure hospitalizations, device diagnostic data, New York Heart Association (NYHA) class improvement, and defibrillator therapy were evaluated from clinical data, in‐office interrogations, and remote monitoring throughout the follow‐up period. Complication‐free survival favored the CRT‐DX group with 92.5% without a major complication compared to 85.0% in the CRT‐D cohort (P = .0495; 95% confidence interval: 0.1%‐14.9%) over a mean follow‐up of 1.3 and 1.4 years, respectively. Incidence of all‐cause mortality, heart failure hospitalizations, NYHA changes at 6 months postimplant, and percent of LV pacing during CRT therapy were similar in both device cohorts. Inappropriate shocks were more frequent in the CRT‐D cohort with 5.8% of subjects receiving an inappropriate shock vs 0.8% in the CRT‐DX cohort.ConclusionThe results of this subanalysis demonstrate that the CRT‐DX system can provide similar CRT responses and significantly fewer complications when compared to a similar cohort with a conventional three‐lead CRT‐D system.