Assessment of myocardial strain patterns in patients with left bundle branch block using cardiac magnetic resonance.

Recently, a classification with four types of septal longitudinal strain patterns was described using echocardiography, suggesting a pathophysiological continuum of left bundle branch block (LBBB)-induced left ventricle (LV) remodeling. The aim of this study was to assess the feasibility of classifying these strain patterns using cardiovascular magnetic resonance (CMR), and to evaluate their association with LV remodeling and myocardial scar. Single center registry included LBBB patients with septal flash (SF) referred to CMR to assess the cause of LV systolic dysfunction. Semi-automated feature-tracking cardiac resonance (FT-CMR) was used to quantify myocardial strain and detect the four strain patterns. A total of 115 patients were studied (age 66 ± 11 years, 57% men, 28% with ischemic heart disease). In longitudinal strain analysis, 23 patients (20%) were classified in stage LBBB-1, 37 (32.1%) in LBBB-2, 25 (21.7%) in LBBB-3, and 30 (26%) in LBBB-4. Patients at higher stages had more prominent septal flash, higher LV volumes, lower LV ejection fraction, and lower absolute strain values (p < 0.05 for all). Late gadolinium enhancement (LGE) was found in 55% of the patients (n = 63). No differences were found between the strain patterns regarding the presence, distribution or location of LGE. Among patients with LBBB, there was a good association between strain patterns assessed by FT-CMR analysis and the degree of LV remodeling and LV dysfunction. This association seems to be independent from the presence and distribution of LGE.

Incidence, Risk Factors, and Outcomes Associated With Permanent Pacemaker Implantation Following Tricuspid Valve Surgery.

BACKGROUND: Data regarding permanent pacemaker (PPM) implantation following tricuspid valve surgery (TVS) are limited. We sought to evaluate its incidence, risk factors, and outcomes. METHODS AND RESULTS: Medicare beneficiaries who underwent TVS from 2013 to 2020 were identified. Patients who underwent TVS for endocarditis were excluded. The primary exposure of interest was new PPM after TVS. Outcomes included all-cause mortality and readmission with endocarditis or heart failure on follow-up. Among the 13 294 patients who underwent TVS, 2518 (18.9%) required PPM placement. Risk factors included female sex (relative risk [RR], 1.26 [95% CI, 1.17-1.36], P<0.0001), prior sternotomy (RR, 1.12 [95% CI, 1.02-1.23], P=0.02), preoperative second-degree heart block (RR, 2.20 [95% CI, 1.81-2.69], P<0.0001), right bundle-branch block (RR, 1.21 [95% CI, 1.03-1.41], P=0.019), bifascicular block (RR, 1.43 [95% CI, 1.06-1.93], P=0.02), and prior malignancy (RR, 1.23 [95% CI, 1.01-1.49], P=0.04). Tricuspid valve (TV) replacement was associated with a significantly higher risk of PPM implantation when compared with TV repair (RR, 3.20 [95% CI, 2.16-4.75], P<0.0001). After a median follow-up of 3.1 years, mortality was not different in patients who received PPM compared with patients who did not (hazard ratio [HR], 1.02 [95% CI, 0.93-1.12], P=0.7). PPM placement was not associated with a higher risk of endocarditis but was associated with a higher risk of heart failure readmission (HR, 1.28 [95% CI, 1.14-1.43], P<0.001). CONCLUSIONS: PPM implantation frequently occurs after TVS, notably in female patients and patients undergoing TV replacement. Although mortality is not increased, it is associated with higher rates of heart failure rehospitalization.

Risk Assessment of Permanent Pacemaker Implantation After Transcatheter Aortic Valve Implantation in Patients With Preexisting Right Bundle Branch Block.

Preexisting right bundle branch block (RBBB) is the strongest predictor for permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI). However, the risk assessment for new PPI and effective procedural strategy for preventing new PPI in patients with preexisting RBBB are still unclear. This study stratified the new PPI risk after TAVI and investigated the impact of implantation strategy in a preexisting RBBB cohort. We analyzed 237 patients with preexisting RBBB who underwent TAVI. The primary endpoint was the incidence of new PPI. Multivariate analyses investigating predictors for new PPI were performed. The overall PPI rate was 33.3%. Significant baseline predictors for new PPI were combination of RBBB, left anterior or posterior fascicular block, and first-degree atrioventricular block (odds ratio [OR] 2.55, 95% confidence interval [CI] 1.09 to 5.04), high calcium volume of noncoronary cusp (OR 2.08, 95% CI 1.05 to 4.10), and membranous septum (MS) length <2 mm (OR 2.02, 95% CI 1.09 to 3.75) in the univariate analysis and MS length <2 mm (OR 2.25, 95% CI 1.06 to 4.82) in the multivariate analysis. On the multivariate analysis including procedural variables, predilatation (OR 2.41, 95% CI 1.01 to 5.83), self-expanding valves (Corevalve, Evolut R, and Evolut Pro/Pro+; Medtronic Inc., Minneapolis, Minnesota) or mechanical expanding valves (Lotus/Lotus Edge; Boston Scientifics, Marlborough, Massachusetts) (OR 3.00, 95% CI 1.31 to 6.91), and implantation depth > MS length (OR 4.27, 95% CI 1.81 to 10.08) were significantly associated with new PPI. The incidence of new PPI increased according to the number of baseline predictors (0: 20.9%, 1: 34.3%, and ≥2: 52.0%) and procedural predictors (0: 3.7%, 1: 20.9%, 2: 40.5%, and 3: 60.0%). New PPI risk in a preexisting RBBB subset could be stratified by baseline factors. Device selection and implantation strategy considering MS length could prevent new PPI even in these high-risk population.

Is the outcome of elective vs non-elective patients undergoing transcatheter aortic valve implantation different? Results of a single-centre, observational assessment of outcomes at a large university clinic.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) can either be conducted as an elective (scheduled in advance) or a non-elective procedure performed during an unplanned hospital admission. The objective of this study was to compare the outcomes of elective and non-elective TAVI patients. METHODS: This single-centre study included 512 patients undergoing transfemoral TAVI between October 2018 and December 2020; 378 (73.8%) were admitted for elective TAVI, 134 (26.2%) underwent a non-elective procedure. Our TAVI programme entails an optimized fast-track concept aimed at minimizing the total length of stay to ≤ 5 days for elective patients which in the German healthcare system is currently defined as the minimal time period to safely perform TAVI. Clinical characteristics and survival rates at 30 days and 1 year were analysed. RESULTS: Patients who underwent non-elective TAVI had a significantly higher comorbidity burden. Median duration from admission to discharge was 6 days (elective group 6 days versus non-elective group 15 days; p < 0.001), including a median postprocedural stay of 5 days (elective 4 days versus non-elective 7 days; p < 0.001). All-cause mortality at 30 days was 1.1% for the elective group and 3.7% for non-elective patients (p = 0.030). At 1 year, all-cause mortality among elective TAVI patients was disproportionately lower than in non-elective patients (5.0% versus 18.7%, p < 0.001). In the elective group, 54.5% of patients could not be discharged early due to comorbidities or procedural complications. Factors associated with a failure of achieving a total length of stay of ≤ 5 days comprised frailty syndrome, renal impairment as well as new permanent pacemaker implantation, new bundle branch block or atrial fibrillation, life-threatening bleeding, and the use of self-expanding valves. After multivariate adjustment, new permanent pacemaker implantation (odds ratio 6.44; 95% CI 2.59-16.00), life-threatening bleeding (odds ratio 4.19; 95% confidence interval 1.82-9.66) and frailty syndrome (odds ratio 5.15; 95% confidence interval 2.40-11.09; all p < 0.001, respectively) were confirmed as significant factors. CONCLUSIONS: While non-elective patients had acceptable periprocedural outcomes, mortality rates at 1 year were significantly higher compared to elective patients. Approximately only half of elective patients could be discharged early. Improvements in periprocedural care, follow-up strategies and optimized treatment of both elective and non-elective TAVI patients are needed.

Incidence and management of atrioventricular conduction disorders in new-onset left bundle branch block after TAVI: A prospective multicenter study.

BACKGROUND: New-onset left bundle branch block (LBBB) is one of the most frequent complications after transcatheter aortic valve implantation (TAVI) and is associated with delayed high degree atrioventricular (AV) block. OBJECTIVES: The objectives of this study were to determine the incidence of AV block in such a population and to assess the performance and safety of a risk stratification algorithm on the basis of electrophysiology study (EPS) followed by implantation of a pacemaker or implantable loop recorder (ILR). METHODS: This was a prospective open-label study with 12-month follow-up. From June 8, 2015, to November 8, 2018, 183 TAVI recipients (mean age 82.3 ± 5.9 years) were included at 10 centers. New-onset LBBB after TAVI persisting for >24 hours was assessed by electrophysiology study during initial hospitalization. High-risk patients (His-ventricle interval ≥70 ms) were implanted with a dual-chamber pacemaker recording AV conduction disturbance episodes. Patients at lower risk were implanted with an ILR with automatic remote monitoring. RESULTS: A high-grade AV conduction disorder was identified in 56 patients (30.6%) at 12 months. Four subjects were symptomatic, all in the ILR group. No complications were associated with the stratification procedure. Patients with His-ventricle interval ≥70 ms displayed more high-grade AV conduction disorders (53.2% [25 of 47] vs 22.8% [31 of 136]; P < .001). In a multivariate analysis, His-ventricle interval ≥70 ms was independently associated with the occurrence of a high-grade conduction disorder (subdistribution hazard ratio 2.4; 95% confidence interval 1.2-4.8; P = .010). CONCLUSION: New-onset LBBB after TAVI was associated with high rates of high-grade AV conduction disturbances. The stratification algorithm provided safe and valuable aid to management decisions and reliable guidance on pacemaker implantation.

Evaluation of Arrhythmia Prevalence, Management, and Risk Factors in Patients with Transcatheter and Surgically Closed Secundum Atrial Septal Defects.

OBJECTIVE: Atrial septal defect (ASD) accounts for 6-10% of all congenital heart disorders. Secundum ASD closure can be performed surgically or percutaneously. We aimed to identify the various arrhythmias that occur before, during, and after the procedure and evaluate their management. METHODS: The study included a total of 427 patients aged 0-18 years who underwent transcatheter or surgical closure of isolated secundum ASD between January 2008 and January 2020. Postoperative electrocardiogram (ECG) traces, intraoperative arrhythmias, and treatments were recorded for both groups. Echocardiography and ECG were evaluated at postoperative 1 week, 1, 3, and 6 months, and annually thereafter. RESULTS: After transcatheter closure, follow-up basal ECG showed incomplete right bundle branch block pattern in 21 patients and sinus rhythm in 229 patients. After surgical closure, incomplete right bundle branch block pattern was detected in 23 patients, complete right bundle branch block in 3 patients, and complete AV-block (Atrioventricular Block) pattern in 1 patient. The other 150 patients showed sinus rhythm. At least one postoperative follow-up Holter ECG record could be obtained for 104 patients in the transcatheter group and 96 patients in the surgical group. Of 104 patients who underwent transcatheter closure, 97 (93.3%) had normal Holter ECG findings and 7 (6.7%) had arrhythmia. Of the 96 patients who underwent surgical closure, 85 (88.5%) had normal Holter ECG traces and 11 (11.5%) had arrhythmia. There was no statistically significant difference in the frequency of arrhythmia (P = 0.164). CONCLUSION: The higher frequency of arrhythmia in adult studies compared to the pediatric age group once again demonstrates the importance of early diagnosis and treatment of ASD in childhood. The similar incidence of arrhythmia in both groups supports the safety and effectiveness of both closure methods in eligible patients.

Assessment of the QT interval in right bundle branch block.

BACKGROUND: Identifying prolonged QT interval in RBBB has been problematic. METHODS: Four approaches were compared to adjust for the QT prolongation in intermittent RBBB. The implications were assessed in a separate group of 200 persons with established RBBB. RESULTS: In 12 individuals, mean age 74.5 years with intermittent RBBB, the presence of RBBB significantly (p < 0.05) increased the QT interval in each of six different heart rate correction formulae by an amount ranging from 35.4 ms in the Hodges formula to 50.2 ms in the Bazett formula. Four different equations were tested to adjust the QT interval and one approach QTcRBBB = 0.945*QTcRBBB - 26 was the best method to adjust for the increased QT in RBBB as it produced a QT value that was not significantly different from the QT interval in the absence of RBBB in intermittent RBBB.Failure to adjust the QT interval in RBBB produces an overestimate of the QT interval which in some heart rate adjustment formulae was marked. For the Bazett heart rate adjustment approach QTc 450 ms was found in 73.9% of men and QTc over 460 ms was found in 60.6% of women. CONCLUSION: These data suggest the implementation of a new approach to recalculate the QT intervals in RBBB. QTcRBBB = 0.945*QTcRBBB - 26 with an appropriate heart rate adjustment formula (other than the Bazett formula) accurately predicts the QT interval in the absence of RBBB.

Seismocardiography as a tool for assessment of bi-ventricular pacing.

Objective.Conduction-induced heart failure in patients with left bundle branch block (LBBB) can benefit from cardiac resynchronization therapy (CRT). However, some patients are non-responders to the therapy with one contributing factor being poor optimization of the atrioventricular (AV) pacing delay. In this study, we have investigated the pacing-induced changes in the seismocardiogram (SCG).Approach.14 patients with heart failure, LBBB, and CRT were included. SCG was recorded with pacing turned on and off. Based on a mean SCG heartbeat from each patient, fiducial points were annotated, and cardiac timing intervals (CTI) and amplitudes were derived. These were compared between the CRT group and a group of healthy normal subjects (n= 14). Echocardiography was also used to derive CTI. Intervals derived from the SCG and echocardiogram were correlated.Main results.The isovolumetric contraction time (IVCT) derived from SCG was significantly shorter in the CRT group when the pacemaker was turned on (63.2-52.6 ms,p= 0.027). The first peak-to-peak amplitude in the systolic complex was significantly larger with the pacemaker turned on (p= 0.002), as well as the ∣max-min∣ amplitude in the systolic complex (p= 0.003). Isovolumetric relaxation time and left ventricular ejection time (LVET) were not significantly different between pacemaker settings. Compared to normal subjects, IVCT was significantly prolonged with the pacemaker turned off. All amplitudes were significantly larger in the healthy subject group. IVCT and LVET derived from SCG were significantly correlated to the echocardiogram.Significance.IVCT shortened and SCG amplitudes increased in response to CRT, indicating a more efficient ventricular contraction. This demonstrates the possibility to detect cardio-mechanic changes in response to treatment with the SCG. However, for the patients the systolic part of the SCG was abnormal and difficult to characterize, raising concerns about the correct interpretation of the SCG.

Early assessment of ventricular synchronization and function after left bundle-branch-area pacing with right bundle-branch block.

AIM: To evaluate ventricular synchronization and function in patients with right bundle-branch block after left bundle-branch-area pacing (LBBAP) by echocardiography. METHODS: Forty patients who successfully received LBBAP were selected and divided into the right bundle-branch block group (RBBB group) and the non-RBBB group by pre-operation ECG. Echocardiography and follow-up were performed 1 month after operation. Interventricular synchronization was evaluated by tissue Doppler (TDI), tissue mitral annular displacement (TMAD), and interventricular mechanical delay. The tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RVFAC), tricuspid annulus sidewall systolic velocity (TV-s'), left ventricular global ventricular longitudinal strain (GLS), right ventricular free wall longitudinal strain (LS-RV), standard deviation of left ventricular 18 segments peak time difference (SDt-L) and standard deviation of right ventricular free wall 3 segments peak time difference (SDt-R) were applied to evaluate intraventricular synchronization and ventricular function. RESULTS: The difference of displacement peak time of the tricuspid and mitral valves, namely ΔPTTV-MV measured by TMAD, the difference of systolic time to peak of the tricuspid and mitral valves, namely ΔTsTV-MV measured by TDI, were statistically different between the two groups (P < 0.05). Compared with the non-RBBB group, there were no statistically significant differences in the GLS, RVFAC, LS-RV, TAPSE, TV-s', SDt-L, SDt-R (P > 0.05). CONCLUSION: Echocardiography technology including two-dimensional speckle tracking imaging (2D-STI), TDI, and TMAD can effectively analyze interventricular synchronization, intraventricular synchronization, and ventricular function. Although the movement of the right ventricular myocardium in the RBBB group was slightly later than that of the left ventricular myocardium after LBBAP, LBBAP could still be applied in RBBB patients with pacing indication.

Evaluating the role of left ventricle global longitudinal strain in myocardial perfusion defect assessment.

Myocardial perfusion defect, assessed with single photon emission computed tomography (SPECT), is useful for patient management and risk stratification. Left ventricle Global Longitudinal Strain (LV GLS) has gained interest for observing subclinical LV dysfunction. We aimed to investigate the utility of LV GLS in evaluating myocardial perfusion defect. A retrospective study of all patients who underwent SPECT and LV GLS at Tel Aviv Sourasky medical center. Overall, 86 patients were included. LV GLS and SPECT correlated in the base and apex sections for infraction, and in the apex only for ischemia. Adjusted analysis showed a significant correlation between LV GLS of both the mid and apical section and infarction by SPECT, but no association with ischemia. No associations were found by arterial supply territory. A sub-analysis of patients without left bundle branch block (LBBB) strengthened the correlations, with a 58-70% higher chance of both fixed and reversible defects for every 1-unit decrease LV GLS in the mid and apical sections. LV GLS effectively evaluated the presence of infarction by SPECT in the mid and apical sections, particularly in patients without LBBB. Due to its high availability, LV GLS may have a role in evaluating myocardial perfusion defect.

Epicardial fat thickness assessment by multi-slice computed tomography for predicting cardiac outcomes in patients undergoing transcatheter aortic valve implantation.

INTRODUCTION: Chronic inflammation promotes aortic valve calcification. It is known that epicardial fat is a source of inflammation. The aim of this study was to investigate the relationship between epicardial fat thickness, cardiac conduction disorders and outcomes in patients undergoing transcatheter aortic valve implantation (TAVI). METHODS: During a three-year period, 45 patients with severe aortic stenosis who underwent TAVI were recruited to the study. Data were collected retrospectively. Epicardial fat was defined as the adipose tissue between the epicardium and the visceral pericardium. Mean epicardial fat thickness was determined by multi-slice computed tomography, which was performed before the procedure. RESULTS: The average thickness of epicardial fat was 13.06 ± 3.29 mm. This study failed to reveal a significant correlation between epicardial fat thickness and post-procedural left bundle branch block, right bundle branch block, paravalvular aortic regurgitation and pacemaker implantation rates (p > 0.05). CONCLUSIONS: The results of this study failed to show a significant relationship between epicardial fat thickness, cardiac conduction disorders and outcomes, however further studies with larger sample numbers are required to explore the relationship.

Electrophysiologic Implications of Transcatheter Aortic Valve Replacement: Incidence, Outcomes, and Current Management Strategies.

PURPOSE OF REVIEW: Transcatheter aortic valve replacement (TAVR) has changed the paradigm for management of severe aortic stenosis. Despite substantial procedural advancements, conduction system abnormalities remain a common complication following TAVR. In this review, we describe (1) incidence and risk factors for the development of conduction disturbances following TAVR, along with their prognostic significance, (2) the incidence and prognostic significance of new-onset arrhythmias following TAVR, (3) approach to management of perioperative and post-procedural conduction disturbances and arrhythmias, and (4) novel areas of research. RECENT FINDINGS: Conduction disturbances including left bundle branch block (LBBB) and high-grade atrioventricular block (HAVB) remain common issues post-TAVR despite advancements in valve technology and improvements in procedural technique. Despite data showing most conduction abnormalities resolve over time, rates of post-procedural permanent pacemaker implantation remain high. Similarly, rates of new-onset or newly detected arrhythmia, particularly atrial fibrillation, have been widely reported post-implantation of all types of TAVR valves. Recent consensus statements and decision pathway documents have been helpful in standardizing an approach to post-TAVR conduction disturbances. New areas of research show promise both for predicting which patients will develop conduction disturbances post-TAVR and for management of HAVB with novel pacing techniques. On the other hand, management of new-onset or newly detected atrial fibrillation after TAVR remains a significant challenge without standardized treatment strategy.

Assessment of QTc and Risk of Torsades de Pointes in Ventricular Conduction Delay and Pacing: A Review of the Literature and Call to Action.

BACKGROUND: Assessment of the heart rate-corrected QT-interval on the 12-lead electrocardiogram when prescribing medications known to increase the risk of Torsades de Pointes has become a common part of consultation-liaison psychiatry practice. OBJECTIVES: Highlighted by a patient who experienced psychiatric decompensation due to inaccurate interpretation of QTc prolongation in the setting of a wide QRS complex, we aimed to describe the approach to QTc interpretation in patients with ventricular conduction delay. METHODS: We reviewed the current literature on the approach to assessment of prolonged repolarization in patients with ventricular conduction delay due to bundle branch block (BBB) and ventricular pacing. RESULTS: Physicians of any specialty may perform initial electrocardiogram interpretation and should be proficient in the definition, recognition, and understanding of the basic pathophysiology of electrocardiographic abnormalities. We discuss current approaches to assessment of the QT-interval in patients with a wide QRS complex due to bundle branch block and ventricular pacing, including bivariate QTc modification, univariate QT-interval modifications, and use of the JT-interval. CONCLUSIONS: The QT-interval is prolonged ipso facto in patients with a wide QRS complex from ventricular conduction delay/ventricular pacing and must be adjusted for QRS duration. Multiple formulae have been proposed to account for wide QRS complex in this setting with no single universally accepted methodology. We suggest the use of either the Bogossian formula or JT-interval followed by Hodges or Framingham heart-rate correction to adjust for a wide QRS complex. It is critical that the C-L psychiatrist be able to identify a wide QRS complex on the electrocardiogram, understand implications for accurate assessment of prolonged depolarization, and apply an appropriate correction methodology.

Prone and Supine 12-Lead ECG Comparisons: Implications for Cardiac Assessment During Prone Ventilation for COVID-19.

OBJECTIVES: This study sought to describe expected changes in a mirror-image prone electrocardiogram (ECG) compared with normal supine, including a range of cardiac conditions. BACKGROUND: Unwell COVID-19 patients are at risk of cardiac complications. Prone ventilation is recommended but poses practical challenges to acquisition of a 12-lead ECG. The effects of prone positioning on the ECG remain unknown. METHODS: 100 patients each underwent 3 ECGs: standard supine front (SF); prone position with precordial leads attached to front (PF); and prone with precordial leads attached to back in a mirror image to front (PB). RESULTS: Prone positioning was associated with QTc prolongation (PF 437 ± 32 ms vs. SF 432 ± 31 ms; p < 0.01; PB 436 ± 34 ms vs. SF 432 ± 31 ms; p = 0.02). In leads V1 to V3 on PB ECG, a qR morphology was present in 90% and changes in T-wave polarity in 84%. In patients with anterior ischemia, ST-segment changes in V1 to V3 on supine ECG were no longer visible on PB in 100% and replaced by an R-wave in V1. Bundle branch block (BBB) remained detectable in 100% on PB, with left BBB appearing as right BBB on PB in 71% and QRS narrowing with qR in V1 for right BBB. ST-segment/T-wave changes in limb leads and arrhythmia detection were largely unaffected in PB. CONCLUSIONS: As expected, the PB ECG is unreliable for the detection of anterior myocardial injury but remains useful for ST-segment/T-wave abnormalities in limb leads, BBB detection, and rhythm monitoring. The prone ECG is a useful screening tool with diagnostic utility in COVID-19 patients who require prone ventilation.

Gain in real-world cardiac resynchronization therapy efficacy with SyncAV dynamic optimization: Heart failure hospitalizations and costs.

BACKGROUND: SyncAV, a device-based cardiac resynchronization therapy (CRT) algorithm, promotes electrical optimization by dynamically adjusting atrioventricular intervals. OBJECTIVE: The purpose of this study was to evaluate the impact of SyncAV on heart failure hospitalizations (HFHs) and related costs in a real-world CRT cohort. METHODS: Patients with SyncAV-capable CRT devices followed by remote monitoring and enrolled in Medicare fee-for-service for at least 1 year preimplant and up to 2 years postimplant were studied. Patients with SyncAV OFF were 4:1 matched to those with SyncAV ON on preimplant HFH rate, demographics, comorbidities, disease etiology, and left bundle branch block. HFHs were determined from the primary diagnosis of inpatient hospitalizations, and the cost for each event was the sum of Medicare, supplemental insurance, and patient payment. RESULTS: After 4:1 propensity score matching, 3630 patients were studied (mean age 75 ± 8 years; 1386 [38%] female), including 726 (25%) patients with SyncAV ON. The pre-CRT HFH rate was 0.338 HFH events per patient-year. Overall, CRT diminished the HFH rate to 0.204 events per patient-year (P < .001). SyncAV elicited a larger reduction in HFH rate (SyncAV ON: hazard ratio [HR] 0.52; 95% confidence interval [CI] 0.41-0.66; P < .001 and SyncAV OFF: HR 0.68; 95% CI 0.59-0.77; P < .001). After 2 years, the HFH rate was lower in the SyncAV ON group than in the SyncAV OFF group (0.143 HFHs per patient-year vs 0.193 HFHs per patient-year; HR 0.70; 95% CI 0.55-0.89; P = .003) and fewer HFHs were followed by 30-day HFH readmissions (4.41% vs 7.68%; P = .003) and 30-day all-cause hospital readmissions (7.04% vs 10.01%; P = .010). The total 2-year HFH-associated costs per patient were lower with SyncAV ON (difference $1135; 90% CI $93-$2109; P = .038). CONCLUSION: This large, real-world, propensity score-matched study demonstrates that SyncAV CRT is associated with significantly reduced HFHs and associated costs, incremental to standard CRT.

Assessment of ventricular mechanical synchronization after left bundle branch pacing using 2-D speckle tracking echocardiography.

BACKGROUND: The left bundle branch pacing (LBBP) makes the ventricular depolarization closer to the physiological state and shortens QRS duration. The purpose of this study is to explore the ventricular systolic mechanical synchronization after LBBP in comparison with traditional right ventricular pacing (RVP) using two-dimensional strain echocardiography (2D-STE). METHODS: Thirty-two patients who received LBBP (n = 16) or RVP (n = 16) from October 2018 to October 2019 and met the inclusion criteria were included in this retrospective study. Electrocardiogram (ECG) characteristics, pacing parameters, pacing sites, and safety events were assessed before and after implantation. Acquisition and analysis of ventricular systolic synchronization were implemented using 2D-STE. RESULTS: In RVP group, ECG showed left bundle branch block patterns. At LBBP, QRS morphology was in the form of right bundle branch block, and QRS durations were significantly shorter than that of the RVP QRS (109.38 ± 12.89 vs 149.38 \± 19.40 ms, P < .001). Both the maximum time differences (TD) and SDs of the 18-segments systolic time to peak systolic strain were significantly shorter under LBBP than under RVP (TD, 66.62 ± 37.2 vs 148.62 ± 43.67 ms, P < .01; SD, 21.80 ± 12.13 vs 52.70 ± 17.72 ms, P < .01), indicating that LBBP could provide better left ventricular mechanical synchronization. Left and right ventricular pre-ejection period difference was significantly longer in RVP group than in LBBP group (10.23 ± 3.07 vs 39.94 ± 14.81 ms, P < .05), indicating left and right ventricular contraction synchronization in LBBP group being better than in RVP group. CONCLUSION: LBBP is able to provide a physiologic ventricular activation pattern, which results in ventricular mechanical contraction synchronization.

Importance of Preoperative Computed Tomography Assessment of the Membranous Septal Anatomy in Patients Undergoing Transcatheter Aortic Valve Replacement With a Balloon-Expandable Valve.

BACKGROUND: Cardiac conduction disturbance (CD) is the most frequent complication following transcatheter aortic valve replacement (TAVR). This study examined whether the anatomy of the membranous septum (MS) could provide useful information about the risk of CD following TAVR with a balloon-expandable valve (BEV).Methods and Results:Among 132 consecutive patients, 106 (mean age, 85.6±5.1 years; 75 females) were included in the study. Using preoperative CT and angiography, MS length and implantation depth (ID) were assessed. The MS length minus the prosthesis ID was calculated (∆MSID). Correlation between CD, defined as new-onset left-bundle branch block (LBBB) or the need for permanent pacemaker (PPM) within 1 week after the procedure, and MS length were evaluated. A total of 19 patients (18%) developed CD following TAVR. MS length was significantly shorter in these patients than in those without CD (5.3±1.3 vs. 6.6±1.4; P<0.001), and was the important predictor of CD (odds ratio [OR]: 0.43, 95% confidence interval [CI]: 0.27-0.69, P<0.001). When considering the pre- and postprocedural parameters, the ∆MSID was smaller in patients with CD (-1.7±1.5 vs. 0.8±1.9, P<0.001), and emerged as the important predictor of CD (OR: 0.47, 95% CI: 0.33-0.69, P<0.001). CONCLUSIONS: Short MS is associated with an increased risk of CD after TAVR with BEV.