Ventricular Resynchronization Research Articles

New-Onset Left Ventricular Dysfunction After Left Bundle Branch Pacing

New-Onset Left Ventricular Dysfunction After Left Bundle Branch Pacing

Comparison of acute hemodynamic effect of prioritizing ventricular resynchronization vs left ventricular filling during optimization of cardiac resynchronization therapy

Comparison of acute hemodynamic effect of prioritizing ventricular resynchronization vs left ventricular filling during optimization of cardiac resynchronization therapy

Conduction system pacing: overview, definitions, and nomenclature.

Conduction system pacing: overview, definitions, and nomenclature.

Automatic subcutaneous defibrillator screening in patients with intracardiac devices: comparative study depending on the point of pacing

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Subcutaneous defibrillator (S-ICD) has been shown to be effective in the prevention of sudden cardiac death with the advantage of avoiding intravascular access. Although it should not be indicated when pacing indications exists, the need for pacing may arise in the course of underlying heart disease. Before implantation, it is necessary to screen the surface electrocardiogram (ECG) to avoid inappropriate shocks due to overdetection. Published studies so far show a drastic reduction in the percentage of patients eligible for screening with conventional pacing techniques (right ventricular apex, right ventricular outflow tract or resynchronisation with coronary sinus pacing). Purpose The change in screening signal produced by cardiac pacing during is unknown. So far, no studies have been published comparing the outcome of S-ICD screening between different pacing sites, including conduction system pacing (CSP, his and left bundle branch pacing). Our aim is to analyse the success rate of screening and its predictors in patients with cardiac pacing according to the pacing point. Methods A total of 102 patients were screened for S-ICD and divided into 5 groups according to pacing type: His bundle pacing (HBP), left bundle pacing (LBP), right ventricular apex (RVA), right ventricular outflow tract (RVOT) and biventricular cardiac resynchronisation (CRT). There were no significant differences in any variable between the HBP and LBP group, so they were unified as the CSP group. We used a control group of 10 healthy patients with no implantable devices or ECG abnormalities. All patients underwent automatic screening with paced rhythm using the automatic algorithm (Boston Scientific). We considered a suitable screening when at least one vector (primary, secondary or alternative) was positive in both decubitus and standing position, in left or right parasternal position. Results Baseline characteristics by group are summarised in table1. Paced QRS width was lower in the CSP group (135 [120-160] vs 120 [106-120] p=0,001). All healthy controls passed the screening (100%). 39 (97.5%) CSP patients passed the screening, compared to 15 (71.4%) CRT, 14 (70%) RVOT and 4 (19%) RVA. The differences were statistically significant, p < 0.001 (image 1 A & B). In multivariate analysis, only pacing type was shown to be a predictor of positive screening (p 0.001), independent of paced QRS width. Conclusions In our experience, the probability of obtaining a positive screening of the S-ICD is higher with conduction system stimulation than with the other pacing points (AVD, RVOT or CRT).

PO-01-026 STEREOTACTIC CARDIAC RADIOTHERAPY FOR RECURRENT VENTRICULAR TACHYCARDIA IN PRESENCE OF WIRELESS LEFT VENTRICULAR ENDOCARDIAL STIMULATION SYSTEM

PO-01-026 STEREOTACTIC CARDIAC RADIOTHERAPY FOR RECURRENT VENTRICULAR TACHYCARDIA IN PRESENCE OF WIRELESS LEFT VENTRICULAR ENDOCARDIAL STIMULATION SYSTEM

Comparison of methods for delivering cardiac resynchronization therapy: an acute electrical and haemodynamic within-patient comparison of left bundle branch area, His bundle, and biventricular pacing.

Left bundle branch area pacing (LBBAP) is a promising method for delivering cardiac resynchronization therapy (CRT), but its relative physiological effectiveness compared with His bundle pacing (HBP) is unknown. We conducted a within-patient comparison of HBP, LBBAP, and biventricular pacing (BVP). Patients referred for CRT were recruited. We assessed electrical response using non-invasive mapping, and acute haemodynamic response using a high-precision haemodynamic protocol. Nineteen patients were recruited: 14 male, mean LVEF of 30%. Twelve had time for BVP measurements. All three modalities reduced total ventricular activation time (TVAT), (ΔTVATHBP -43 ± 14 ms and ΔTVATLBBAP -35 ± 20 ms vs. ΔTVATBVP -19 ± 30 ms, P = 0.03 and P = 0.1, respectively). HBP produced a significantly greater reduction in TVAT compared with LBBAP in all 19 patients (-46 ± 15 ms, -36 ± 17 ms, P = 0.03). His bundle pacing and LBBAP reduced left ventricular activation time (LVAT) more than BVP (ΔLVATHBP -43 ± 16 ms, P < 0.01 vs. BVP, ΔLVATLBBAP -45 ± 17 ms, P < 0.01 vs. BVP, ΔLVATBVP -13 ± 36 ms), with no difference between HBP and LBBAP (P = 0.65). Acute systolic blood pressure was increased by all three modalities. In the 12 with BVP, greater improvement was seen with HBP and LBBAP (6.4 ± 3.8 mmHg BVP, 8.1 ± 3.8 mmHg HBP, P = 0.02 vs. BVP and 8.4 ± 8.2 mmHg for LBBAP, P = 0.3 vs. BVP), with no difference between HBP and LBBAP (P = 0.8). HBP delivered better ventricular resynchronization than LBBAP because right ventricular activation was slower during LBBAP. But LBBAP was not inferior to HBP with respect to LV electrical resynchronization and acute haemodynamic response.

Conduction system pacing learning curve: Left bundle pacing compared to His bundle pacing.

Conduction system pacing learning curve: Left bundle pacing compared to His bundle pacing.

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Left bundle branch area pacing: A promising modality for cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) is recognized as the first-line management for patients with heart failure (HF) and conduction disorders. As a conventional mode for delivering CRT, biventricular pacing (BVP) improves cardiac function and reduces HF hospitalizations and mortality, but there are still limitations given the high incidence of a lack of response rates. Alternative pacing methods are needed either for primary or rescue therapy. In recent years, conduction system pacing (CSP) has emerged as a more physiological pacing modality for simultaneous stimulation of the ventricles, including His bundle pacing (HBP) and left bundle branch pacing (LBBP). CSP activates the His-Purkinje system, allowing normal ventricular stimulation. However, HBP is technically challenging with a relatively low success rate, high pacing threshold, and failure to correct distal conduction abnormalities. Therefore, LBBP stands out as a novel ideal physiological pacing modality for CRT. Several non-randomized studies compared the feasibility and safety of LBBP with BVP and concluded that LBBP is superior to BVP for delivering CRT with a narrower QRS and greater improvements in left ventricular ejection fraction (LVEF) and New York Heart Association (NYHA) functional class. Concurrently, some studies showed lower and stable pacing thresholds and greater improvement of B-type natriuretic peptide (BNP) levels, as well as better mechanical synchronization and efficiency. LBBP ensures better ventricular electromechanical resynchronization than BVP. In this review, we discuss current knowledge of LBBP, compare LBBP with BVP, and explore the potential of LBBP to serve as an alternative primary therapy to realize cardiac resynchronization.

Predictive values of left ventricular mechanical dyssynchrony for CRT response in heart failure patients with different pathophysiology

Predictive values of left ventricular mechanical dyssynchrony for CRT response in heart failure patients with different pathophysiology

Octogenarian with Severe Left Ventricular Dysfunction and Cardiac Resynchronization TherapyDefibrillator Device: Successful Anesthesia Management for Hip Arthroplasty

Cardiac resynchronization therapy has emerged as a key component in management of advanced heart failure with reduced ejection fraction in selected subset of geriatric patients. The burgeoning burden of comorbidities, complexity of these devices and aging population presenting for surgeries necessitates peri-operative physicians to be cognizant and confident to handle these challenging cases. Limited literature about anesthesia management of patients implanted with these devices add to the situational challenge. We present a case of elderly gentleman with ischemic cardiomyopathy and cardiac resynchronization therapy-defibrillator device who underwent hip replacement under general anesthesia. Understanding the disease and the device are the crucial and definitive exigencies to manage such cases.

Incidence of morbidity and mortality in a cohort of congenital complete heart block patients followed over 40 years.

Incidence of morbidity and mortality in a cohort of congenital complete heart block patients followed over 40 years.

PO-621-06 SHORTER LEARNING CURVE OF LEFT BUNDLE PACING COMPARED TO HIS BUNDLE PACING

PO-621-06 SHORTER LEARNING CURVE OF LEFT BUNDLE PACING COMPARED TO HIS BUNDLE PACING

Analysis of SIRT4 gene single-nucleotide polymorphisms in a Han Chinese population with dilated cardiomyopathy.

Aim: We aimed to investigate the association of SIRT4 gene polymorphisms with the susceptibility and prognosis of dilated cardiomyopathy (DCM) in a Chinese population. Materials & methods: A total of 369 controls and 373 DCM patients were enrolled. Three tag single-nucleotide polymorphisms (rs2261612, rs2522138 and rs16950058) on SIRT4 were evaluated. Results: G carriers of rs2261612 were associated with the susceptibility of DCM in codominant, dominantand overdominant genetic models (all p<0.01). Furthermore, the AG/GG and AG genotype of rs2261612 in dominant and overdominant models correlated with poor prognosis of DCM, independent of left ventricular ejection fraction and cardiac resynchronization therapy (p<0.001). Conclusion:SIRT4 polymorphisms were associated with the susceptibility and prognosis of DCM in a Chinese population.

Conduction system pacing in heart failure patients

Direct conduction system pacing delivers more physiological cardiac activation and can potentially correct intraventricular conduction disturbances and restore normal activation pathways. Permanent pacing that maintains cardiac electromechanical synchrony is essential in heart failure and reduced left ventricular ejection fraction. Conduction system pacing has recently emerged as an alternative to right ventricular pacing and biventricular resynchronization therapy. In this article, we review conduction system pacing in heart failure patients.

B-PO02-187 THE DOMINANT MECHANISM OF BIVENTRICULAR PACING IN LEFT BUNDLE BRANCH BLOCK IS SHORTENING OF ATRIOVENTRICULAR DELAY

B-PO02-187 THE DOMINANT MECHANISM OF BIVENTRICULAR PACING IN LEFT BUNDLE BRANCH BLOCK IS SHORTENING OF ATRIOVENTRICULAR DELAY

B-PO03-023 HIS BUNDLE PACING ACHIEVES BETTER VENTRICULAR SYNCHRONY THAN BIVENTRICULAR PACING IN PATIENTS WITH SCAR IN THE LEFT VENTRICULAR FREE WALL

B-PO03-023 HIS BUNDLE PACING ACHIEVES BETTER VENTRICULAR SYNCHRONY THAN BIVENTRICULAR PACING IN PATIENTS WITH SCAR IN THE LEFT VENTRICULAR FREE WALL

An electrographic AV optimization for the maximum integrative atrioventricular and ventricular resynchronization in CRT

BackgroundAtrioventricular (AV) delay could affect AV and ventricular synchrony in cardiac resynchronization therapy (CRT). Strategies to optimize AV delay according to optimal AV synchrony (AVopt-AV) or ventricular synchrony (AVopt-V) would potentially be discordant. This study aimed to explore a new AV delay optimization algorithm guided by electrograms to obtain the maximum integrative effects of AV and ventricular resynchronization (opt-AV).MethodsForty-nine patients with CRT were enrolled. AVopt-AV was measured through the Ritter method. AVopt-V was obtained by yielding the narrowest QRS. The opt-AV was considered to be AVopt-AV or AVopt-V when their difference was < 20 ms, and to be the AV delay with the maximal aortic velocity–time integral between AVopt-AV and AVopt-V when their difference was > 20 ms.ResultsThe results showed that sensing/pacing AVopt-AV (SAVopt-AV/PAVopt-AV) were correlated with atrial activation time (Pend-As/Pend-Ap) (P < 0.05). Sensing/pacing AVopt-V (SAVopt-V/PAVopt-V) was correlated with the intrinsic AV conduction time (As-Vs/Ap-Vs) (P < 0.01). The percentages of patients with more than 20 ms differences between SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V were 62.9% and 57.1%, respectively. Among them, opt-AV was linearly correlated with SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V. The sensing opt-AV (opt-SAV) = 0.1 × SAVopt-AV + 0.4 × SAVopt-V + 70 ms (R2 = 0.665, P < 0.01) and the pacing opt-AV (opt-PAV) = 0.25 × PAVopt-AV + 0.5 × PAVopt-V + 30 ms (R2 = 0.560, P < 0.01).ConclusionThe SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V were correlated with the atrial activation time and the intrinsic AV conduction interval respectively. Almost half of the patients had a > 20 ms difference between SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V. The opt-AV could be estimated based on electrogram parameters.

Atrioventricular shortening is the dominant mechanism of benefit of biventricular pacing in left bundle branch block

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): British Heart Foundation Background Cardiac resynchronization therapy delivered via biventricular pacing is thought to improve haemodynamic function through resynchronization of ventricular activation. Biventricular pacing also improves ventricular filling by shortening atrioventricular delay. Quantifying the relative contributions of these two mechanisms requires atrioventricular delay to be altered while left bundle branch block is preserved. This occurs when the His bundle is paced at an output below the left bundle branch block correction threshold. Purpose We performed His bundle pacing with preservation of left bundle branch block to measure the relative contributions of atrioventricular delay shortening and ventricular resynchronisation to the overall haemodynamic benefit of biventricular pacing. Methods Patients with left bundle branch block referred for conventional cardiac resynchronization therapy with biventricular pacing were recruited. Using a high precision, beat-by-beat systolic blood pressure assessment protocol, we assessed the haemodynamic effects of biventricular pacing and temporary His bundle pacing with left bundle branch block preservation at a full range of atrioventricular delays. We used non-invasive epicardial mapping (ECGI) to assess left ventricular activation time. Left bundle branch block preservation was defined as &amp;lt;20ms shortening of the interval between intrinsic His potential to QRS offset to the interval from stimulation to QRS offset in His bundle pacing. Results In 19 patients, His bundle pacing with preservation of left bundle branch block produced a peak systolic blood pressure improvement of 5.1mmHg (95% confidence interval: 2.2 to 8.0, p = 0.0013) compared to AAI pacing. In 16 of these patients, biventricular pacing was performed and produced a peak systolic blood pressure improvement of 7.1mmHg (3.8 to 10.4, p &amp;lt; 0.001) compared to AAI pacing. The mean within-patient improvement in systolic blood pressure from His bundle pacing with preservation of left bundle branch block to biventricular pacing was 2.6mmHg (-0.4 to 5.7, p = 0.053, n = 16). The mean improvement in systolic blood pressure with left bundle branch block-preserved His bundle pacing was 63% of the mean improvement with biventricular pacing. Change in left ventricular activation time from intrinsic rhythm to 12-lead-ECG-defined left bundle branch block preservation was 0.1ms (-6.4 to 6.7, n = 19). Conclusion Biventricular pacing in left bundle branch block improves haemodynamic function through ventricular resynchronization and shortening of atrioventricular delay. The majority of benefit appears to be produced by atrioventricular delay shortening. When left bundle branch block is not corrected, His bundle pacing may still produce considerable haemodynamic improvement through this mechanism. Abstract Figure.

Frequency, predictors, and prognosis of heart failure with improved left ventricular ejection fraction: a single-centre retrospective observational cohort study.

AimsAn improved left ventricular ejection fraction (HFiEF) was observed across heart failure (HF) patients with a reduced or mid‐range ejection fraction (HFrEF or HFmrEF, respectively). We postulated that HFiEF patients are clinically distinct from non‐HFiEF patients.Methods and resultsA total of 447 patients hospitalized due to a clinical diagnosis of HF (LVEF <50% at baseline) were enrolled from September 2017 to September 2019. Echocardiogram re‐evaluation was conducted repeatedly over 6 months of follow‐up after discharge. The primary endpoint included the composite of HF hospitalization and all‐cause mortality. Subjects (n = 184) with HFiEF (defined as an absolute LVEF improvement≥10%) were compared with 263 non‐HFiEF (defined by <10% improvement in LVEF) subjects. Multivariable Cox regression was performed and identified younger age, smaller left ventricular end diastolic dimension (LVEDD), beta‐blocker use, AF ablation and cardiac resynchronization therapy (CRT) as independent predictors of HFiEF. According to Kaplan–Meier analysis, HFiEF subjects had lower cardiac composite outcomes (P = 0.002) and all‐cause mortality (P = 0.003) than non‐HFiEF subjects. Multivariate Cox survival analysis revealed that non‐HFiEF (compared with HFiEF) was an independent predictor of both the primary endpoints (HR = 0.679, 95% CI: 0.451–0.907, P = 0.012), which was driven by all‐cause mortality (HR = 0.504, 95% CI: 0.256–0.991, P = 0.047).ConclusionsThese data confirm that compared with non‐HFiEF, HFiEF is a distinct HF phenotype with favourable clinical outcomes.