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Background Aim Method Results Conclusion Sacubitril/valsartan (an angiotensin receptor‐neprilysin inhibitors [ARNI]) might improve atrial fibrillation (AF) condition, but its added value remains controversial.We aimed to analyse the effect of ARNI on AF burden.We conducted a single‐centre, retrospective self‐controlled study in a tertiary centre. Data were retrieved from January 2019–January 2023. All cardiac resynchronisation therapy‐implantable cardioverter defibrillator (CRT‐D) carriers on ARNI were included if implantation had been at least 3 months before drug initiation. Proarrhythmic events, equal time length control (before ARNI initiation), and exposure (after ARNI initiation) periods were defined. Echocardiographic data were retrieved if they were up to 1 year old before ARNI initiation and if they were available 3 months to 1 year after initiation. AF burden was defined by frequency and median value of paroxysmal events and the overall variation in AF status was determined. Ethical approval was granted by the Ethics Committee of the Centro Hospitalar e Universitário de Coimbra (Reference no: PI OBS.SF.174‐2022) and the study conforms with the Declaration of Helsinki.Seventy‐two patients were included in the study (73.3% men). After ARNI, there was a reduction in New York Heart Association functional class ± standard deviation (2.00 ± 0.75 to 1.85 ± 0.61, p = 0.043) and an increase in left ventricular ejection fraction ± standard deviation (from 31.67% ± 9.28% vs 37.33% ± 14.49%, p = 0.027). Before ARNI initiation, 34 patients did not have AF, 19 had paroxysmal AF, 15 had permanent AF, and 2 had persistent AF. The total amount of AF episodes (91 vs 44, p = 0.808) and median paroxysmal episodes (among those with paroxysmal AF or no AF) (5 vs 3, p = 0.121) were numerically reduced after ARNI initiation, though variation was not statistically significant. No differences were found as well regarding ventricular arrhythmias or device therapies.ARNI did not significantly decrease the number of AF paroxysmal episodes or median number of paroxysmal events per patient. Even though ARNI may have a positive impact on AF burden of heart failure patients, larger studies are needed to provide unequivocal evidence. [ABSTRACT FROM AUTHOR]

Currently, there is no widely accepted criterion for judging the efficacy of CRT treatment. Patients underwent CRT implantation have most often been classified as either responders or non-responders based on the occurrence or absence of reverse remodelling following CRT. Based on this definition, nearly one-third of patients are considered as non-responders with a less favourable prognosis compared to responders. Recent recommendations have revised the previous terminologies. Accordingly, the CRT non-responder definition have-been re-defined as those who deteriorate (progressors) and remain stable for years (non-progressor) after CRT implantation. Considering the progressive nature of HF, non-progression could still represent a response to the device therapy and thereby classifying these patients as non-responders might be misleading. The background of the suboptimal CRT response is multifactorial, requiring a multidisciplinary approach for improving the effectiveness of CRT treatment. Therefore, we care must be taken on the appropriate patient selection and optimisation of the medications prior to implantation, currently available technical options and innovations during the intervention, device optimisation post-implantation, as well as on the management of comorbidities.

Introduction: The efficacy of de novo cardiac resynchronisation therapy (CRT) in patients with heart failure (HF), left ventricular systolic dysfunction (LVSD), and a broad QRS morphology is well established. However, the optimal stage for upgrading patients with existing pacemakers (PPMs) or implantable cardioverter-defibrillators (ICDs) and HF with high-burden right ventricular (RV) pacing remains uncertain. Thus, this multicentre retrospective analysis compared patients with pre-existing PPMs or ICDs who underwent CRT upgrades to investigate the appropriate stage for CRT implantation in these patients and to assess the validity of treating both PPM and ICD recipients under the same recommendation level in the current guidelines. Materials and Methods: A total of 151 participants underwent analysis in this study, comprising 93 upgrades to cardiac resynchronisation therapy with pacemaker (CRT-P) and 58 upgrades to cardiac resynchronisation therapy with defibrillator (CRT-D) across three centres in the UK. The aim of the study was to investigate the safety and efficacy of upgrading to CRT from an existing conventional pacemaker or an ICD in the context of high-burden RV pacing. The analysis was conducted separately for each group, assessing changes in echocardiographic parameters, functional New York Heart Association (NYHA) class, and procedure-related complications. Results: The PPM group had a higher percentage RVP burden compared to the ICD group. Post-upgrade, NYHA functional class and EF and LV volumes improved in both groups; however, the response to an upgrade from a pacemaker was greater compared to an upgrade from an ICD. Post-procedural complication risks were similar across the two subgroups but significantly higher compared to de novo implantation. Conclusions: Within the CRT-P subgroup, participants exhibited better responses than their CRT-D counterparts, evident both in echocardiographic improvements and clinical outcomes. Furthermore, patients with non-ischemic cardiomyopathy (NICM) were better responders than those with ischaemic cardiomyopathy. These findings suggest that international guidelines should consider approaching each subgroup separately in the future. [ABSTRACT FROM AUTHOR]

Implantable cardiac devices are a vital treatment option in the management of tachy/brady-arrhythmias and heart failure with conduction disease. In the recent years, these devices have become increasingly sophisticated, with high implantation success rates and longevity. However, these devices are not without risks and complications, which need to be carefully considered before implantation. In an era of rapidly evolving cardiac device therapies, this review article will provide an update on the literature and outline some of the emerging technologies that aim to maximise the efficiency of implantable devices and reduce complications. We discuss novel pacing techniques, including alternative pacing sites in anti-bradycardia and biventricular pacing, as well as the latest evidence surrounding leadless device technologies and patient selection for implantable device therapies. [ABSTRACT FROM AUTHOR]

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. 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. 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. Upgrading to CRT is a safe and effective procedure regarding improvement of functional class, left ventricular function status and post-procedural outcome. [ABSTRACT FROM AUTHOR]

Abstract Cardiac resynchronisation therapy (CRT) improves prognosis in patients with heart failure (HF) however the role of ABO blood groups and Rhesus factor are poorly understood. We hypothesise that blood groups may influence clinical and survival outcomes in HF patients undergoing CRT. A total of 499 patients with HF who fulfilled the criteria for CRT implantation were included. Primary outcome of all-cause mortality and/or heart transplant/left ventricular assist device was assessed over a median follow-up of 4.6 years (IQR 2.3–7.5). Online repositories were searched to provide biological context to the identified associations. Patients were divided into blood (O, A, B, and AB) and Rhesus factor (Rh-positive and Rh-negative) groups. Mean patient age was 66.4 ± 12.8 years with a left ventricular ejection fraction of 29 ± 11%. There were no baseline differences in age, gender, and cardioprotective medication. In a Cox proportional hazard multivariate model, only Rh-negative blood group was associated with a significant survival benefit (HR 0.68 [0.47–0.98], p = 0.040). No association was observed for the ABO blood group (HR 0.97 [0.76–1.23], p = 0.778). No significant interaction was observed with prevention, disease aetiology, and presence of defibrillator. Rhesus-related genes were associated with erythrocyte and platelet function, and cholesterol and glycated haemoglobin levels. Four drugs under development targeting RHD were identified (Rozrolimupab, Roledumab, Atorolimumab, and Morolimumab). Rhesus blood type was associated with better survival in HF patients with CRT. Further research into Rhesus-associated pathways and related drugs, namely whether there is a cardiac signal, is required.

Introduction: Cardiac resynchronisation therapy is ineffective in 30–40% of patients with heart failure with reduced ejection fraction. Targeting non-scarred myocardium by selecting the site of latest mechanical activation using echocardiography has been suggested to improve outcomes but at the cost of increased resource utilisation. The interval between the beginning of the QRS complex and the local LV lead electrogram (QLV) might represent an alternative electrical marker. Aims: To determine whether the site of latest myocardial electrical and mechanical activation are concordant. Methods: This was a single-centre, prospective pilot study, enrolling patients between March 2019 and June 2021. Patients underwent speckle-tracking echocardiography (STE) prior to CRT implantation. Intra-procedural QLV measurement and R-wave amplitude were performed in a blinded fashion at all accessible coronary sinus branches. Pearson's correlation coefficient and Cohen's Kappa coefficient were utilised for the comparison of electrical and echocardiographic parameters. Results: A total of 20 subjects had complete data sets. In 15, there was a concordance at the optimal site between the electrically targeted region and the mechanically targeted region; in four, the regions were adjacent (within one segment). There was discordance (≥2 segments away) in only one case between the two methods of targeting. There was a statistically significant increase in procedure time and fluoroscopy duration using the intraprocedural QLV strategy. There was no statistical correlation between the quantitative electrical and echocardiographic data. Conclusions: A QLV-guided approach to targeting LV lead placement appears to be a potential alternative to the established echocardiographic-guided technique. However, it is associated with prolonged fluoroscopy and overall procedure time. [ABSTRACT FROM AUTHOR]

Cardiac resynchronisation therapy (CRT) is an established treatment for patients with symptomatic heart failure with reduced left ventricular ejection fraction (LVEF ≤ 35%; HFrEF) and conduction disturbances (QRS duration ≥ 130 ms). The presence of mechanical dyssynchrony (MD) on echocardiography has been hypothesised to be of predictive value in determining indication for CRT. This study investigated the impact of MD (apical rocking [AR] and septal flash [SF]) on long-term survival in CRT recipients. HFrEF patients (n = 425; mean age 63.0 ± 10.6 years, 72.3% male, 60.7% non-ischaemic aetiology) with a guideline-derived indication for CRT underwent device implantation. MD markers were determined at baseline and after a mean follow-up of 11.5 ± 8.0 months; long-term survival was also determined. AR and/or SF were present in 307 (72.2%) participants at baseline. During post-CRT follow-up, AR and/or SF disappeared in 256 (83.4%) patients. Overall mean survival was 95.9 ± 52.9 months, longer in women than in men (109.1 ± 52.4 vs. 90.9 ± 52.4 months; p < 0.001) and in younger (< 60 years) versus older patients (110.6 ± 53.7 vs. 88.6 ± 51.1 months; p < 0.001). Patients with versus without MD markers at baseline generally survived for longer (106.2 ± 52.0 vs. 68.9 ± 45.4 months; p < 0.001), and survival was best in patients with resolved versus persisting MD (111.6 ± 51.2 vs. 79.7 ± 47.6 months p < 0.001). Age and MD at baseline were strong predictors of long-term survival in HFrEF patients undergoing CRT on multivariate analysis. Novel echocardiography MD parameters in HFrEF CRT recipients predicted long-term mediated better outcome, and survival improved further when AR and/or SF disappear after CRT implantation. [ABSTRACT FROM AUTHOR]

A complex transvenous lead extraction (TLE) procedure could be associated with lower success and higher complication rates in inexperienced hands. In this study, we aim to assess the factors that determine procedural difficulty in TLE. We retrospectively studied 200 consecutive patients undergoing TLE in a single referral centre from June 2020 to December 2021. Lead extraction difficulty was assessed by the success of simple manual traction with or without a locking stylet, the need for advanced extraction tools and the number of tools required to extract the lead. Logistic and linear regression analyses were used to determine the factors independently affecting these 3 parameters. 363 leads were extracted from 200 patients (79% males, mean age 66.85 years). The indication for TLE was device-related infection in 51.5%. Multivariate analysis revealed the lead indwelling time to be the only factor affecting the 3 parameters of difficulty. Passive fixation leads and dual coil leads increased procedural difficulty by affecting 2 parameters each. Factors that affected one parameter included infected leads, coronary sinus leads, older age of the patient and a history of valvular heart disease, all associated with a simpler procedure. Right ventricular leads were associated with a more complex one. The most important factor that increased TLE procedural difficulty was a longer lead indwelling time, followed by passive fixation and dual-coil leads. Other contributing factors were the presence of infection, coronary sinus leads, older patients, a history of valvular heart disease and right ventricular leads. [ABSTRACT FROM AUTHOR]

Background Edge-to-edge intervention is the most common trans-catheter procedure performed for isolated severe tricuspid regurgitation in high-surgical-risk patients. However, it creates an obstacle for future right ventricular (RV) procedures such as implantation of cardiac implantable electronic devices (CIEDs). Reports of the management of CIED implantation after tricuspid edge-to-edge therapy are scarce. Case summary A 76-year-old woman suffered from severe tricuspid regurgitation with New York Heart Association three symptoms despite optimal medical therapy. After a thorough evaluation, the heart team recommended the TriClip procedure as the treatment of choice. However, 12 months after a successful TriClip procedure, rapid atrial fibrillation needed to be addressed with CIED implantation and atrioventricular (AV) node ablation. Pre-procedural planning included the intended posterior location of the CIED to avoid interference with the implanted clip and future AV node ablation. With an additional left ventricular lead positioned anteriorly to the RV lead, the posterior position of the RV lead was secured. Under peri-procedural trans-oesophageal echocardiography (TEE), the planned procedures were performed successfully. Discussion A blind manoeuvring of the RV lead may damage the edge-to-edge tricuspid device. In addition, friction due to an overly close contract between the RV lead and the edge-to-edge device may damage the RV lead. A successful and safe CIED implantation and atrioventricular node ablation can be performed after tricuspid edge-to-edge therapy with careful planning and its precise execution under TEE surveillance. [ABSTRACT FROM AUTHOR]

Implantable cardiac devices are a vital treatment option in the management of tachy/brady-arrhythmias and heart failure with conduction disease. In the recent years, these devices have become increasingly sophisticated, with high implantation success rates and longevity. However, these devices are not without risks and complications, which need to be carefully considered before implantation. In an era of rapidly evolving cardiac device therapies, this review article will provide an update on the literature and outline some of the emerging technologies that aim to maximise the efficiency of implantable devices and reduce complications. We discuss novel pacing techniques, including alternative pacing sites in anti-bradycardia and biventricular pacing, as well as the latest evidence surrounding leadless device technologies and patient selection for implantable device therapies.

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Objective: To assess heart failure patients by speckle tracking echocardiography before cardiac resynchronisation therapy implantation to predict the outcome. Method: The descriptive follow-up study was conducted at Kafrelsheikh and Mansoura University Hospitals, Egypt, from January 2020 to May 2022, and comprised heart failure patients of either gender who had ejection fraction ≤35%, QRS width &gE;130msec and symptomatic even on optimal medical therapy. They were subjected to full clinical evaluation, electrocardiogram, basic and speckle tracking echocardiography with calculation of maximal septal to lateral delay at baseline and 3 months after cardiac resynchronisation therapy implantation. The patients were classified according to response into group I having non-responders, group II having patients who improved clinically only, and group III having responders both in clinical and echocardiographic terms. Data was analysed using SPSS 23. Results: Of the 38 patients with mean age 55.24±11.23 years, 16(42%) were females and 22(57.9%) were males. There were 7(18.4%) patients in group I, 7(18.4%) in group II and 24(63.2%) in group III. There was a positive significant correlation between response to cardiac resynchronisation therapy CRT and increase in maximal septal to lateral delay at baseline (p

Background: Left bundle branch pacing (LBBP) is a novel physiological pacing technique which may serve as an alternative to biventricular pacing (BVP) for the delivery of cardiac resynchronisation therapy (CRT). This study assessed the feasibility and outcomes of LBBP in comparison to BVP. Methods: LBBP was attempted in 40 consecutive patients as the first-line method for delivering CRT. To evaluate LBBP versus BVP, 40 patients with identical inclusion criteria who received BVP were compared with the LBBP group. Acute success rate, complications, functional and echocardiographic outcomes as well as hospitalisation for heart failure and all-cause mortality 6 months after implantation were evaluated. Results: LBBP was successfully performed in 31 (78%) patients and resulted in significant QRS narrowing (from 166 ± 16 to 123 ± 18 ms, p < 0.001), improvement in left ventricular ejection fraction (LVEF; from 28 ± 8 to 43 ± 12%, p < 0.001) and New York Heart Association functional class (from 2.8 ± 0.5 to 1.6 ± 0.6, p < 0.001) at 6 months. No LBBP-related complications occurred. Compared to BVP, LBBP resulted in a greater reduction in QRS duration (44 ± 17 vs 15 ± 26 ms, p < 0.001) with comparable absolute improvement in LVEF (15.2 ± 11.7 vs 9.6 ± 12.1%, p = 0.088). Hospitalisation for heart failure and all-cause mortality were similar in the two groups. Conclusions: LBBP is feasible and was safe in 78% of patients with favourable electrical resynchronisation and functional improvement and may serve as an alternative to BVP. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic resulted in a significant decrease in the number of hospital admissions for severe emergent cardiovascular diseases during lockdowns worldwide. This study aimed to determine the impact of both the first and the second Danish nationwide lockdown on the implantation rate of cardiac implantable electronic devices (CIEDs). We retrospectively analysed the number of CIED implantations performed in Denmark and stratified them into 3-week intervals. The total number of de novo CIED implantations decreased during the first lockdown by 15.5% and during the second by 5.1%. Comparing each 3-week interval using rate ratios, a significant decrease in the daily rates of the total number of de novo and replacement CIEDs (0.82, 95% CI [0.70, 0.96]), de novo CIEDs only (0.82, 95% CI [0.69, 0.98]), and non-acute pacemaker implantations (0.80, 95% CI [0.63, 0.99]) was observed during the first interval of the first lockdown. During the second lockdown (third interval), a significant decrease was seen in the daily rates of de novo CIEDs (0.73, 95% CI [0.55, 0.97]), and of pacemakers in total during both the second (0.78, 95% CI [0.62, 0.97]) and the third (0.60, 95% CI [0.42, 0.85]) intervals. Additionally, the daily rates of acute pacemaker implantation decreased during the second interval (0.47, 95% CI [0.27, 0.79]) and of non-acute implantation during the third interval (0.57, 95% CI [0.38, 0.84]). A significant increase was observed in the number of replacement procedures during the first interval of the second lockdown (1.70, 95% CI [1.04, 2.85]). Our study found only modest changes in CIED implantations in Denmark during two national lockdowns. [ABSTRACT FROM AUTHOR]

Background: Primary prophylactic implantable cardioverter-defibrillators (ICDs) in patients with non-ischaemic cardiomyopathy (NICMP) remains controversial. This study sought to assess the benefit of ICD therapy with or without cardiac resynchronisation therapy (CRT) in patients with NICMP. In addition, data were compared with real-world clinical data to perform a risk/benefit analysis. Methods: Relevant randomised clinical trials (RCTs) published in meta-analyses since DANISH, and in PubMed, EMBASE and Cochrane databases from 2016 to 2020 were identified. The benefit of ICD therapy stratified by CRT use was assessed using random effects meta-analysis techniques. Results: Six RCTs were included in the meta-analysis. Among patients without CRT, ICD use was associated with a 24% reduction in mortality (hazard ratio [HR]: 0.76; 95% confidence interval [CI]: 0.62–0.93; P = 0.008). In contrast, among patients with CRT, a CRT-defibrillator was not associated with reduced mortality (HR: 0.74, 95% CI 0.47–1.16; P = 0.19). For ICD therapy without CRT, absolute risk reduction at 3‑years follow-up was 3.7% yielding a number needed to treat of 27. Conclusion: ICD use significantly improved survival among patients with NICMP who are not eligible for CRT. Considering CRT, the addition of defibrillator therapy was not significantly associated with mortality benefit compared with CRT pacemaker. [ABSTRACT FROM AUTHOR]

Cardiac Resynchronisation Therapy (CRT) has demonstrated short and long-term benefit in heart failure with reduced ejection fraction (HFrEF), including ischaemic (ICM) and non-ischaemic cardiomyopathy. However, there is a paucity of evidence regarding its role in cardiac sarcoidosis (CS). Consecutive CS patients with CRT and baseline left ventricle ejection fraction (LVEF)≤40 referred to one specialist hospital in London between November 2008-March 2023 were retrospectively reviewed. The baseline characteristics, short-term echocardiographic, clinical parameters and long-term primary and secondary outcomes were compared against a cohort of ICM patients with CRT and baseline LVEF≤40. Patients with incomplete follow-up were excluded. The primary endpoint was a composite of all-cause mortality, cardiac transplantation or heart failure hospitalisation. Secondary endpoint included ventricular arrhythmic events. 63 CS and 93 ICM patients were analysed. A greater proportion of ICM patients male with older ages overall (both p < 0.01), whereas a larger proportion of CS patients had atrioventricular block and heart failure hospitalisations (both p < 0.01). Both cohorts demonstrated significant serial increase in left ventricular (LV) ejection fraction and reduction in LV end-systolic and end-diastolic volumes (p < 0.01). After a mean follow up of 40.9 (±32.0) months, the primary and secondary endpoint was reached by significantly more CS patients (log-rank p = 0.008 and log-rank p = 0.004). Age (HR: 1.12 (95 %CI 1.06-1.17, p < 0.001) and presence of CS (HR: 8.33 (95 %CI 3.03-22.93, p < 0.001) were independent predictors of the primary endpoint on multivariable analysis. CS patients with CRT demonstrated reverse remodelling, but had adverse long-term primary and secondary outcomes when compared to ICM patients. [Display omitted] [ABSTRACT FROM AUTHOR]

Introduction: Cardiac resynchronisation therapy is ineffective in 30–40% of patients with heart failure with reduced ejection fraction. Targeting non-scarred myocardium by selecting the site of latest mechanical activation using echocardiography has been suggested to improve outcomes but at the cost of increased resource utilisation. The interval between the beginning of the QRS complex and the local LV lead electrogram (QLV) might represent an alternative electrical marker. Aims: To determine whether the site of latest myocardial electrical and mechanical activation are concordant. Methods: This was a single-centre, prospective pilot study, enrolling patients between March 2019 and June 2021. Patients underwent speckle-tracking echocardiography (STE) prior to CRT implantation. Intra-procedural QLV measurement and R-wave amplitude were performed in a blinded fashion at all accessible coronary sinus branches. Pearson’s correlation coefficient and Cohen’s Kappa coefficient were utilised for the comparison of electrical and echocardiographic parameters. Results: A total of 20 subjects had complete data sets. In 15, there was a concordance at the optimal site between the electrically targeted region and the mechanically targeted region; in four, the regions were adjacent (within one segment). There was discordance (≥2 segments away) in only one case between the two methods of targeting. There was a statistically significant increase in procedure time and fluoroscopy duration using the intraprocedural QLV strategy. There was no statistical correlation between the quantitative electrical and echocardiographic data. Conclusions: A QLV-guided approach to targeting LV lead placement appears to be a potential alternative to the established echocardiographic-guided technique. However, it is associated with prolonged fluoroscopy and overall procedure time.

His bundle pacing (HBP) is proven to be a safe and effective alternative pacing modality that, in addition, avoids pacemaker-induced cardiomyopathy (PICM) by achieving a “physiological” ventricular stimulation, via the native conduction system. Indications include various causes of bradycardia requiring anti-bradycardic pacing, inadequately controlled atrial fibrillation requiring AV node ablation and established PICM. In addition, HBP may also be used as an alternative therapy for patients with heart failure (HF) and an indication for cardiac resynchronization therapy (CRT). Available data show several advantages of HBP with regard to preservation or restoration of intra- and inter-ventricular synchronization; improvement in left ventricular ejection fraction, functional status and quality of life; decrease in atrial fibrillation incidence and improvement in HF hospitalization rates, compared with conventional pacing. Nevertheless, superiority in terms of mortality rates has not been consistently demonstrated, and the long-term efficacy and safety of HBP remain to be proven. In the present manuscript, we review the status of HBP and present our current experience with this novel pacing modality.

Introduction: The impact of remote monitoring (RM) on clinical outcomes in heart failure (HF) patients with cardiac resynchronisation therapy-defibrillator (CRT-D) implantation is controversial. This study sought to evaluate the performance of an RM follow-up protocol using modified criteria of the PARTNERS HF trial in comparison with a conventional follow-up scheme. Material and methods: We compared cardiovascular (CV) mortality (primary endpoint) and hospitalisation events for decompensated HF, and the number of ambulatory in-office visits (secondary endpoint) in CRT-D implanted patients with automatic RM utilising daily transmissions (RM group, n = 45) and conventional follow-up (CFU group, n = 43) in a single-centre observational study. Results: After a median follow-up of 25 months, a significant advantage was seen in the RM group in terms of CV mortality (1 vs. 6 death event, p = 0.04), although RM follow-up was not an independent predictor for CV mortality (HR = 0.882; 95% CI: 0.25-3.09; p = 0.845). Patient CV mortality was independently influenced by hospitalisation events for decompensated HF (HR = 3.24; 95% CI: 8-84; p = 0.022) during follow-up. We observed significantly fewer hospitalisation events for decompensated HF (8 vs. 29 events, p = 0.046) in the RM group. Furthermore, a decreased number of total (161 vs. 263, p < 0.01) and unnecessary ambulatory in-office visits (6 vs. 19, p = 0.012) were seen in the RM group as compared to the CFU group. Conclusions: Follow-up of CRT-D patients using automatic RM with daily transmissions based on modified PARTNERS HF criteria enabled more effective ambulatory interventions leading indirectly to improved CV survival. Moreover, RM directly decreased the number of HF hospitalizations and ambulatory follow-up burden compared to CRT-D patients with conventional follow-up. [ABSTRACT FROM AUTHOR]

Correctly diagnosing left bundle branch block (LBBB) is fundamental, as LBBB occurs frequently in heart failure and may trigger a vicious cycle of progressive left ventricular dysfunction. Moreover, a correct diagnosis of LBBB is pivotal to guide cardiac resynchronisation therapy. Since the LBBB diagnostic criteria were recently updated by the European Society of Cardiology (ESC), we assessed their diagnostic accuracy compared with the previous ESC 2013 definition. We further discuss the complexity of defining LBBB within the context of recent insights into the electromechanical pathophysiology of LBBB. [ABSTRACT FROM AUTHOR]

Introduction: In responders, cardiac resynchronisation therapy (CRT) results in improved left ventricular (LV) function and reduced atrial arrhythmia. The aim of this meta-analysis was to assess the potential relationship between the left atrium (LA) volume and CRT response.Material and methods: We systematically searched all electronic databases up to August 2018 in order to select clinical trials and observational studies that assessed the predictive value of LA volume index (LAVI) of CRT response. Left ventricular end-systolic volume (LVESV) reduction ≥ 15 ml and/or LV ejection fraction (EF) increase ≥ 10% were the documented criteria for positive CRT response.Results: A total of 2191 patients recruited in 10 studies with mean follow-up duration of 10.5 months were included in this meta-analysis. The pooled analysis showed that CRT responders had lower baseline LAVI compared to non-responders, with a weighted mean difference (WMD) of -5.89% (95% CI: -9.47 to -3.22, p < 0.001). At follow-up, LAVI fell in the CRT responders (WMD -4.36%, 95% CI: -3.54 to -5.17, p < 0.001) compared to non-responders (WMD 1.45 %, 95% CI: -0.75 to 3.65, p = 0.20). The mean change of LAVI in the CRT responders was related to the fall in LVESV, β = -1.02 (-1.46 to -0.58), p < 0.001 and the increase in LVEF, β = 2.02 (1.86 to 4.58), p = 0.001. A baseline LAVI < 34 ml/m2 predicted CRT response with summary sensitivity 0.80% (0.53-0.95), specificity 0.74% (0.53-0.89), and odds ratio > 11.Conclusions: Baseline LAVI predicts CRT response, and its reduction reflects devise-related LA remodelling. These results emphasis the role of LAVI assessment as an integral part of cardiac function response to CRT. [ABSTRACT FROM AUTHOR]

Copyright of Heart & Vascular Diseases / Choroby Serca & Naczyn is the property of VM Medica-VM Group (Via Medica) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Left bundle branch area pacing (LBBAP) has recently been introduced as a physiological pacing technique with synchronous left ventricular activation. It was our aim to evaluate the feasibility and learning curve of the technique, as well as the electrical characteristics of LBBAP. Methods and results: LBBAP was attempted in 80 consecutive patients and electrocardiographic characteristics were evaluated during intrinsic rhythm, right ventricular septum pacing (RVSP) and LBBAP. Permanent lead implantation was successful in 77 of 80 patients (96%). LBBAP lead implantation time and fluoroscopy time shortened significantly from 33 ± 16 and 21 ± 13 min to 17 ± 5 and 12 ± 7 min, respectively, from the first 20 to the last 20 patients. Left bundle branch (LBB) capture was achieved in 54 of 80 patients (68%). In 36 of 45 patients (80%) with intact atrioventricular conduction and narrow QRS, an LBB potential (LBBpot) was present with an LBBpot to onset of QRS interval of 22 ± 6 ms. QRS duration increased significantly more during RVSP (141 ± 20 ms) than during LBBAP (125 ± 19 ms), compared to 130 ± 30 ms without pacing. An even clearer difference was observed for QRS area, which increased significantly more during RVSP (from 32 ± 16 µVs to 73 ± 20 µVs) than during LBBAP (41 ± 15 µVs). QRS area was significantly smaller in patients with LBB capture compared to patients without LBB capture (43 ± 18 µVs vs 54 ± 21 µVs, respectively). In patients with LBB capture (n = 54), the interval from the pacing stimulus to R‑wave peak time in lead V6 was significantly shorter than in patients without LBB capture (75 ± 14 vs 88 ± 9 ms, respectively). Conclusion: LBBAP is a safe and feasible technique, with a clear learning curve that seems to flatten after 40–60 implantations. LBB capture is achieved in two-thirds of patients. Compared to RVSP, LBBAP largely maintains ventricular electrical synchrony at a level close to intrinsic (narrow QRS) rhythm. [ABSTRACT FROM AUTHOR]

Background: Left bundle branch (LBB) pacing is a novel pacing technique which may serve as an alternative to both right ventricular pacing for symptomatic bradycardia and cardiac resynchronisation therapy (CRT). A substantial amount of data is reported by relatively few, highly experienced centres. This study describes the first experience of LBB pacing in a high-volume device centre. Methods: Success rates (i.e. the ability to achieve LBB pacing), electrophysiological parameters and complications at implant and up to 6 months of follow-up were prospectively assessed in 100 consecutive patients referred for various pacing indications. Results: The mean age was 71 ± 11 years and 65% were male. Primary pacing indication was atrioventricular (AV) block in 40%, CRT in 42%, and sinus node dysfunction or refractory atrial fibrillation prior to AV node ablation in 9% each. Baseline left ventricular ejection fraction was < 50% in 57% of patients, mean baseline QRS duration 145 ± 34 ms. Overall LBB pacing was successful in 83 of 100 (83%) patients but tended to be lower in patients with CRT pacing indication (69%, p = ns). Mean left ventricular activation time (LVAT) during LBB pacing was 81 ms and paced QRS duration was 120 ± 19 ms. LBB capture threshold and R‑wave sense at implant was 0.74 ± 0.4 mV at 0.4 ms and 11.9 ± 5.9 V and remained stable at 6‑month follow-up. No complications occurred during implant or follow-up. Conclusion: LBB pacing for bradycardia pacing and resynchronisation therapy can be easily adopted by experienced implanters, with favourable success rates and safety profile. [ABSTRACT FROM AUTHOR]

Aim: To evaluate whether left bundle branch block with residual conduction (rLBBB) is associated with worse outcomes after cardiac resynchronisation therapy (CRT). Methods: All consecutive CRT implants at our institution between 2006 and 2013 were identified from our local device registry. Pre- and post-implant patient specific data were extracted from clinical records. Results: A total of 690 CRT implants were identified during the study period. Prior to CRT, 52.2% of patients had true left bundle branch block (LBBB), 19.1% a pacing-induced LBBB (pLBBB), 11.2% a rLBBB, 0.8% a right bundle branch block (RBBB), and 16.5% had a nonspecific intraventricular conduction delay (IVCD) electrocardiogram pattern. Mean age at implant was 67.5 years (standard deviation [SD] = 10.6), mean left ventricular ejection fraction (LV EF) was 25.7% (SD = 7.9%), and mean QRS duration was 158.4 ms (SD = 32 ms). After CRT, QRS duration was significantly reduced in the LBBB (p

Patients with cardiac implantable electronic devices (CIED) undergoing radiotherapy (RT) becoming more common due to ageing of the population. With newer CIEDs implementing the complementary metal-oxide semiconductor (CMOS) technology which allows the miniaturisation of CIED, it is also more susceptible to RT. Effects of RT on CIED ranges from device interference, device operational/memory errors to permanent damage. These malfunctions can cause life threatening clinical effects. Cumulative dose is not the only component of RT that causes CIED malfunction, as neutron use and dose rate effect also affects CIEDs. The management of this patient cohort in clinical practice is inconsistent due to lack of a consistent guideline from manufacturers and physician specialty societies. Our review will focus on the current clinical practice and the recent updated guidelines of managing patients with CIED undergoing RT. We aim to simplify the evidence and provide a simple and easy to use guide based on the recent guidelines. [ABSTRACT FROM AUTHOR]

Background: Optimization of cardiac resynchronization therapy (CRT) is often time‐consuming and therefore underused in a clinical setting. Novel device‐based algorithms aiming to simplify optimization include a dynamic atrioventricular delay (AVD) algorithm (SyncAV, Abbott) and multipoint pacing (MPP, Abbott). This study examines the acute effect of SyncAV and MPP on electrical synchrony in patients with newly and chronically implanted CRT devices. Methods: Patients with SyncAV and MPP enabled devices were prospectively enrolled during implant or scheduled follow‐up. Blinded 12‐lead electrocardiographic acute measurements of QRS duration (QRSd) were performed for intrinsic QRSd (Intrinsic), bi‐ventricular pacing (BiV), MPP, BiV with SyncAV at default offset 50 ms (BiVSyncAVdef), BiV with SyncAV at patient‐specific optimised offset (BiVSyncAVopt), MPP with SyncAV at default offset 50 ms (MPPSyncAVdef), and MPP with SyncAV at patient‐specific optimised offset (MPPSyncAVopt). Results: Thirty‐three patients were enrolled. QRSd for Intrinsic, BiV, MPP, BiVSyncAVdef, BiVSyncAVopt, MPPSyncAVdef, MPPSyncAVopt were 160.4 ± 20.6 ms, 141.0 ± 20.5 ms, 130.2 ± 17.2 ms, 121.7 ± 20.9 ms, 117.0 ± 19.0 ms, 121.2 ± 17.1 ms, 108.7 ± 16.5 ms respectively. MPPSyncAVopt led to greatest reduction of QRSd relative to Intrinsic (−31.6 ± 11.1%; p <.001), showed significantly shorter QRSd compared to all other pacing configurations (p <.001) and shortest QRSd in every patient. Shortening of QRSd was not significantly different between newly and chronically implanted devices (−51.6 ± 14.7 ms vs. −52.7 ± 21.9 ms; p =.99). Conclusion: SyncAV and MPP improved acute electrical synchrony in CRT. Combining both technologies with patient‐specific optimization resulted in greatest improvement, regardless of time since implantation. Whats new Novel device‐based algorithms like a dynamic AVD algorithm (SyncAV, Abbott) and multipoint pacing (MPP, Abbott) aim to simplify CRT optimization. Our data show that a combination of patient tailored SyncAV optimization and MPP results in greatest improvement of electrical synchrony in CRT measured by QRS duration, regardless if programmed in newly or chronically implanted devices. This is the first study to our knowledge to examine a combination of these device‐based algorithms. The results help understanding the ideal ventricular excitation in heart failure. [ABSTRACT FROM AUTHOR]

The benefit of de novo cardiac resynchronisation therapy (CRT) implantation in selected patients with heart failure is well known. The number of upgrade procedures is increasing but data on clinical response and outcome are less well documented as compared to de novo implantation. To investigate the efficacy and outcome of CRT upgrade procedures in patients with existing cardiac implantable electronic devices (CIEDs). Baseline characteristics, change in New York Heart Association (NYHA) functional class, echocardiographic parameters, life-threatening ventricular tachyarrhythmias, all-cause mortality and mode of death were evaluated in CRT patients with the comparison between de novo and upgrade CRT procedures. About 410 patients (CRT upgrade/de novo CRT, n = 97/313) were followed for 63.5 ± 38.1 months. Upgrade patients were older (75.5 ± 8.1 vs 69.9 ± 10.7 years; p < 0.001), had more often an ischaemic cause of heart failure (58.8% vs 45.4%; p = 0.021), a higher NYHA functional class (p = 0.004) and a higher comorbidity burden. Improvement in left ventricular ejection fraction (LVEF) was higher in the de novo CRT group (8.4 ± 9.9 vs 11.0 ± 10.3%; p = 0.035). Clinical response was similar between both groups (60.5 vs 62.5%; p = 0.793), as was mortality at 1 year (8.2 vs 5.8%; p = 0.351) and at last follow-up (33.0 vs 28.8%; p = 0.447). The proportion of cardiovascular related deaths was similar between both groups (46.9% vs 38.9%; p = 0.531). Patients with CRT upgrade procedures have similar symptomatic improvements, as well as 1 year and long-term outcome as compared to patients with de novo CRT implantation. [ABSTRACT FROM AUTHOR]

Background: Bipolar active fixation (BipolarAFL) and quadripolar passive fixation left-ventricular leads (QuadPFL) have been designed to reduce the risk of phrenic nerve stimulation (PNS), enable targeted left-ventricular pacing, and overcome problems of difficult coronary venous anatomy and lead dislodgment. This study sought to report the long-term safety and performance of a BipolarAFL, Medtronic Attain Stability 20066, compared to QuadPFL.Methods: We performed a single-operator retrospective analysis of 81 patients receiving cardiac resynchronization therapy (CRT) (36 BipolarAFL, 45 QuadPFL). Immediate implant data and electrical and clinical data during follow-up (FU) were analyzed.Results: BipolarAFL has been chosen in patients with significantly larger estimated vein diameter (at the lead tip: 7.2 ± 4.1 Fr vs. 4.1 ± 2.3 Fr, p < 0.001) without significant time difference until the final lead position was achieved (BipolarAFL: 20.9 ± 10.5 min, vs. QuadPFL: 18.9 ± 8.9 min, p = 0.35). At 12 month FU no difference in response rate to CRT was recorded between BipolarAFL and QuadPFL according to left ventricular end-systolic volume (61.1 vs. 60.0%, p = 0.82) and New York Heart Association (66.7 vs. 62.2%, p = 0.32). At median FU of 48 months (IQR: 44–54), no lead dislodgment occurred in both groups but a significantly higher proportion of PNS was recorded in QuadPFL (13 vs. 0%, p < 0.05). Electrical parameters were stable during FU in both groups without significant differences.Conclusion: BipolarAFL can be implanted with ease in challenging coronary venous anatomy, shows excellent electrical performance and no difference in clinical outcome compared to QuadPFL.

Purpose: Cardiac resynchronisation therapy (CRT) has proven mortality benefits for heart failure patients with moderate to severe systolic left ventricular dysfunction and evidence of a left bundle branch block. Determining responders to this therapy can be difficult due to the presence of myocardial fibrosis and scar. Left ventricular global longitudinal strain (LV GLS) is a robust and sensitive measure of myocardial function and fibrosis that has significant prognostic value for a plethora of cardiac pathologies. Our aim was to perform a systematic review of the value of LV GLS for predicting outcomes in patients undergoing CRT. Methods: A systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) protocol for reporting on systematic reviews and meta-analyses. An electronic search of all English, adult publications in EMBASE, MEDLINE/PubMed and the Cochrane Database of Systematic reviews was undertaken. Results: The search yielded, 9 studies that included 3,981 patients with symptomatic heart failure, undergoing CRT implantation with LV GLS utilised as a predictor of all-cause mortality, cardiovascular death, rehospitalisation, LVAD implantation/ heart transplantation or left ventricular reverse remodelling. Significant heterogeneity was observed in study outcome measures, included populations, LV-GLS cut-offs and follow-up definitions, resulting in the inability to reliably conduct a meta-analyses. Overall, pre-CRT LV GLS was found to be a predictor of outcome post CRT insertion. Conclusions: In conclusion, all studies implied that incrementally abnormal baseline LV GLS pre-CRT implantation was associated with a long term poorer outcome.

Introduction: Multipoint pacing (MPP) has been proposed as an effective way to improve cardiac resynchronisation therapy (CRT) response. We performed a systematic review and meta‐analysis evaluating the efficacy of CRT delivered via MPP compared to conventional CRT. Methods: A literature search was performed from inception to January 2021 for studies in Medline, Embase and Cochrane databases, comparing MPP to conventional CRT with a minimum of 6 months follow‐up. Randomised and nonrandomised studies were assessed for relevant efficacy data including echocardiographic (left ventricular end systolic volume [LVESV] and ejection fraction) or functional changes (New York Heart Association [NYHA] class/Clinical Composite Score). Subgroup analyses were performed by study design and programming type. Results: A total of 7 studies with a total of 1390 patients were included in the final analysis. Overall, MPP demonstrated greater echocardiographic improvement than conventional CRT in nonrandomised studies (odds ratio [OR]: 5.33, 95% confidence interval [CI]: [3.05–9.33], p <.001), however, was not significant in randomised studies (OR: 1.86, 95% CI: [0.91–3.79], p =.086). There was no significant difference in LVESV reduction >15% (OR: 1.96, 95% CI: [0.69–5.55], p =.20) or improvement by ≥1 NYHA class (OR: 2.49, 95% CI: [0.74–8.42], p =.141) when comparing MPP to conventional CRT. In a sub analysis, MPP programmed by widest anatomical separation (MPP‐AS) signalled greater efficacy, however, only 120 patients were included in this analysis. Conclusion: Overall MPP was more efficacious in nonrandomised studies, and not superior when assessed in randomised studies. There was considerable heterogeneity in study design making overall interpretation of results challenging. Widespread MPP programming in all CRT patients is currently not justified. Further large, randomised studies with patient‐specific programming may clarify its effectiveness. [ABSTRACT FROM AUTHOR]

Purpose: Inappropriate implantable cardioverter-defibrillator (ICD) shocks are associated with greater healthcare resource utilization, poorer quality-of-life, and higher mortality. We aimed to investigate the performance of enhanced supraventricular tachycardia (SVT) discrimination algorithms (morphology discrimination, rate stability, and sudden or chamber onset) for reducing inappropriate ICD therapies in patients with ICD/cardiac resynchronization therapy devices. Methods: This prospective, non-randomized, multicenter study (ReduceIT) study took place at 56 sites across Germany and Estonia. Adults at risk of sudden cardiac death undergoing St. Jude Medical™ ICD or CRT-D implantation were included. The primary endpoint was freedom from inappropriate ICD shock at 12 months and was analyzed in the intention to treat (ITT) and per-protocol population. Results: Overall, 733 patients (65.9 ± 11.4 years) were included, of which 40.9% and 59.1% received a single- and dual-chamber detection device, respectively. During follow-up (median 11.9 [0–21.6] months), 96.3% of patients experienced no inappropriate therapy (ITT). The sensitivity, specificity, and accuracy for VT/VF were 91.9%, 95.5%, and 94.7%, respectively. In the per-protocol population (n = 620), the proportion of patients free from inappropriate shock at 12 months was 98.4% (n = 610; 95% CI 97.1–99.2%) and exceeded the expected value of 93% (p < 0.0001) which was derived from the rates in the SPICE, ATPonFastVT, and DECREASE studies. A total of 44 patients (6.0%) died during follow-up, 19 deaths were cardiac-related which is consistent with a meta-analysis of EMPIRIC, MADIT-RIT, ADVANCE III, and PROVIDE. Serious device and procedure-related adverse effects occurred in 9.8% of patients. Conclusions: In ICD/CRT-D devices with advanced SVT discriminators, device programming according to clinical setting and detection chamber significantly reduces the rate of inappropriate ICD shocks without compromising patient safety. The algorithms and settings described herein have particular clinical importance and their employment may be of benefit to ICD recipients. [ABSTRACT FROM AUTHOR]

Introduction In responders, cardiac resynchronisation therapy (CRT) results in improved left ventricular (LV) function and reduced atrial arrhythmia. The aim of this meta-analysis was to assess the potential relationship between the left atrium (LA) volume and CRT response. Material and methods We systematically searched all electronic databases up to August 2018 in order to select clinical trials and observational studies that assessed the predictive value of LA volume index (LAVI) of CRT response. Left ventricular end-systolic volume (LVESV) reduction ≥ 15 ml and/or LV ejection fraction (EF) increase ≥ 10% were the documented criteria for positive CRT response. Results A total of 2191 patients recruited in 10 studies with mean follow-up duration of 10.5 months were included in this meta-analysis. The pooled analysis showed that CRT responders had lower baseline LAVI compared to non-responders, with a weighted mean difference (WMD) of –5.89% (95% CI: –9.47 to –3.22, p < 0.001). At follow-up, LAVI fell in the CRT responders (WMD –4.36%, 95% CI: –3.54 to –5.17, p < 0.001) compared to non-responders (WMD 1.45 %, 95% CI: –0.75 to 3.65, p = 0.20). The mean change of LAVI in the CRT responders was related to the fall in LVESV,  = –1.02 (–1.46 to –0.58), p < 0.001 and the increase in LVEF,  = 2.02 (1.86 to 4.58), p = 0.001. A baseline LAVI 11. Conclusions Baseline LAVI predicts CRT response, and its reduction reflects devise-related LA remodelling. These results emphasis the role of LAVI assessment as an integral part of cardiac function response to CRT.

Objective: Revision to cardiac resynchronisation therapy (CRT) in patients with existing pacemakers with worsening heart failure (HF) can improve symptoms and cardiac function. We identify factors that predict improvement in left ventricular ejection fraction (LVEF) within a year of CRT revision. Methods: We performed a retrospective study of 146 consecutive patients (16% female, mean age 73 ± 11 years, mean LVEF 27 ± 8%) undergoing revision to CRT (January 2012 to May 2018) in a single tertiary centre. LVEF was measured pre-revision and 3, 6 and 12 months post-upgrade. Results: At 6 months, 68% of patients demonstrated improvement in LVEF (mean ΔLVEF + 6.7% ± 9.6). Compared to patients in atrial fibrillation (AF), patients with sinus rhythm had a greater improvement in LVEF at 6 months (sinus 8.4 ± 10.3% vs. AF 4.2 ± 8.0%, p = 0.02). Compared to ischaemic cardiomyopathy (ICM), patients with non-ischaemic cardiomyopathy (NICM) had a greater improvement in LVEF at 6 months (NICM 8.4 ± 9.8% vs ICM 4.8 ± 9.2%, p = 0.05). Patients with RV pacing ≥40% at baseline had a greater improvement in LVEF at 6 months (≥40% RV pacing 9.3 ± 10.2 vs.

Response to cardiac resynchronisation therapy (CRT) in patients with heart failure depends on the degree of correction of electromechanical dyssynchrony between the left and right ventricles (LV, RV). It is not known whether chronic programming of interventricular (VV) intervals based on characterisation of myocardial strain at different pacing intervals performed acutely would have better long-term clinical outcomes. We hence aimed to evaluate this relationship between speckle tracking strain patterns and rates at different VV intervals and long-term clinical outcomes of programmed VV pacing in patients with CRT in a prospective, longitudinal follow-up study. We assessed echocardiographic effects, myocardial strain patterns and rates in acute settings at VV intervals; 'LV Off', 'VV0', 'VV60' and 'RV Off' to provide 'RV-only', 'simultaneous BiV', 'sequential LV–RV' and 'LV-only' pacing respectively in 338 patients (age, 67.5 ± 10.3 years; male, 70%) with CRT. Thereafter, devices were programmed chronically to VV60, and long-term clinical outcomes were assessed. With VV0, VV60 and LV only pacing, LVEF improved to 33.6 ± 12.3%, 40.0 ± 11.4% and 42.6 ± 11.2%, respectively, from 23.7 ± 10.2% at baseline (p <.001). Incremental improvement in strain occurred with VV0, VV60 and LV only pacing; greatest with LV only pacing. At 1 year, 23% patients had NYHA III-IV compared to 96% at baseline (p <.001). In patients with CRT, different VV timings show significant differences in acute myocardial strain patterns and rates, and LVEF. These changes are markedly favourable with LV-only and sequential LV–RV pacing, the latter with chronic programming also results in long-term clinical improvement. [ABSTRACT FROM AUTHOR]