bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synchronization of repolarization after cardiac resynchronization therapy: time course and relation to reverse remodeling
Authors: Prinzen F , Verzaal NJ , Van Deursen CJM , Pezzuto S , Wecke L , Vernooy K , Delhaas T , Auricchio A 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The changes in ventricular repolarization after cardiac resynchronization therapy (CRT) are poorly understood.

Objective
Address this knowledge gap using a multimodality approach including electrocardiographic and echocardiographic measurements in patients and patient-specific computational modeling.

Methods
In a cohort of consecutive CRT patients, electrocardiographic and echocardiographic measurements were performed before and at various intervals after CRT, both during CRT-ON and temporary CRT-OFF. T-wave area was calculated from vectorcardiograms, reconstructed from the 12-lead ECG. Computer simulations were performed using a patient-specific eikonal model of cardiac activation with spatially varying action potential duration (APD) and repolarization rate, based on a patient’s ECG and MRI-based chest and cardiac anatomy.

Results
In 33 patients T-wave area during CRT-OFF doubled within 5 days of CRT (left figure) while other repolarization markers like QT-interval and peak-to-end T-wave interval hardly changed. Patients with T-wave area increase above the median increase showed a significantly larger increase in left ventricular ejection fraction than those with smaller T-wave area increase (+11±8% vs. +6±6%, respectively; p&lt;0.05, n=76). Computer simulations (figure, right) show the sequence of depolarization and repolarization before CRT, obtained by the patient-specific model (BL LBBB) and following Acute CRT. Repolarization after chronic CRT-OFF was obtained by matching the measured CRT-OFF ECG with that provided by the model. The best match was obtained by changes in APD following chronic CRT that are opposite to the change in CRT-induced activation time. Such APD changes were associated with a reduction in right and left ventricular dispersion in repolarization during chronic CRT-ON compared with acute CRT-ON.

Conclusions
T-wave area during CRT-OFF is a sensitive marker for adaptations in ventricular repolarization after CRT that are related to CRT-induced reverse remodeling and may involve an inverse relation between activation time and APD, coinciding with lower right and left ventricular dispersion of repolarization and with larger increases in LV ejection fraction during chronic CRT.
Impact of the ESC 2021 guidelines on cardiac pacing and cardiac resynchronization therapy left bundle branch block definition on CRT patient selection and survival
Authors: Rijks J , Ghossein M , Luermans J , Maass A , Meine M , Prinzen F , Linz D , Vernooy K , Van Stipdonk A 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The recently published ESC 2021 guidelines on cardiac pacing and cardiac resynchronization therapy (CRT) underwent significant changes compared to the ESC 2013 guidelines regarding the definition of left bundle branch block (LBBB) by adding notching or slurring in 2 adjacent leads as a prerequisite. The level of recommendation for CRT depends on diagnosing LBBB or non-LBBB. These changes may have a significant impact on patient selection for CRT, as fewer patients may be diagnosed with LBBB and may therefore get a lower level of recommendation for CRT.

Purpose
In this study we investigated the impact of these changes in LBBB definition on patient selection and heart transplantation/left ventricular assist device (LVAD) free survival.

Methods
A large multicenter CRT database, consisting of consecutive patients implanted with a CRT device between 2001 and 2015 in 3 university hospitals in the Netherlands, was used for this study. Patient selection, device implantation, lead positioning and follow-up were according to then prevailing guidelines and local protocols. For this study, patients were selected with baseline sinus rhythm, QRS duration &gt;130ms, and without right ventricular pacing. Patients were stratified according to ESC 2013 and ESC 2021 guideline definitions on LBBB.

Results
The current analyses included 1.202 CRT patients. 66% of patients were male with an age of 66±11 years. Heart failure etiology was ischemic in 49% of patients with baseline left ventricular ejection fraction of 25% and baseline NYHA class II-III in 93% of patients. There is a considerable difference in LBBB diagnoses when stratifying patients according to ESC 2013 and ESC 2021 guideline definitions as especially the number of LBBB patients is reduced from 80.9% to 31.6% (Figure 1). Heart transplantation/LVAD free survival analyses when stratifying according to ESC 2013 LBBB definition showed significant separation of the curves (p&lt;0.0001) (Figure 2). Furthermore, there was a significant difference between the wide (QRS&gt;150ms) LBBB and wide non-LBBB subgroup concerning heart transplantation/LVAD free survival (p&lt;0.0001). In contrast, there was no significant separation of the curves when stratifying according to ESC 2021 LBBB definition (Figure 2).

Conclusion
The changes made in LBBB definition in the ESC 2021 CRT guidelines lead to a difference in stratification of LBBB and non-LBBB. The ESC 2013 LBBB definition, however, seems to be better in predicting heart transplantation/LVAD free survival after CRT.
Longer left ventricular activation time is associated with lower mortality and risk of heart failure hospitalization in CRT recipients
Authors: Marinko S , Platonov PG , Carlson J , Borgquist R 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): ALF Governmental Funding within the Swedish health care system

Introduction
Cardiac resynchronization therapy (CRT) is an established treatment for heart failure in selected patients. Longer QRS duration has been showed to correlate to clinical outcome, but measures global activation time, rather than the left ventricular dyssynchrony that CRT aims to correct. This study therefore evaluated the incremental value of using Left Ventricular Activation Time (LVAT) for prediction of outcome after CRT.

Methods
Medical records of 445 patients receiving CRT implants at a large-volume tertiary care center were retrospectively evaluated. Digital electrocardiograms (ECG) before and after CRT implantation were collected and ECG parameters were analysed in relation to a primary composite endpoint of time to heart failure hospitalisation or death from any cause. LVAT was defined as time from QRS onset to maximum positive deflection in lead V6 (Figure 1).

Results
Patients were followed for up to 6 years (median 2.7), during which 147 patients (33%) reached the primary endpoint (93 deaths and 103 heart failure hospitalisations). LVAT was measured pre-implant (median 71ms [58-88]) and post-implant (median 74ms [57-96]). There was no CRT-mediated reduction in LVAT (delta -2.3ms +/-31ms, p=0.27). When divided into quartiles, preoperative LVAT had a significant association with clinical outcome (HR 0.76 [0.64-0.90] per increasing quartile, p=0.001), also shown in a median-split Kaplan Meier curve (Figure 2, log rank p=0.001). Multivariate hazard ratio (adjusted for relevant clinical variables) was 0.83; [0.69-0.99]; p=0.047). There was an interaction between LVAT and ECG morphology (p=0.033), and when ECG groups were analysed separately, there was only a significant result for those with native left bundle branch block morphology. Post-implant LVAT, or change in LVAT, did not correlate with the primary endpoint (p=0.25 and p=0.38 respectively.

Conclusion
In CRT recipients, longer pre-implant LVAT was associated with lower risk of heart failure hospitalisation and death during a follow-up of up to 6 years. This association was mainly seen in patients with native LBBB prior to implant. No association was seen with post-CRT LVAT and clinical outcome. If confirmed in prospective trials, evaluation of preoperative LVAT may help optimise patient selection for CRT.
Measurement of electrical dyssynchrony in CRT patients: 12-lead ECG versus 96-lead body surface map
Authors: Sedova K , Van Dam P , Sbrollini A , Burattini L , Blahova M , Necasova L , Sramko M , Kautzner J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant agency AZV, Ministry of Health of the Czech Republic

Background
Quantification of electrical dyssynchrony would allow optimization of lead placement and timing in patients with CRT. The standard deviation of activation times (SDAT) derived from body surface maps (BSM) was proposed as a measure of electrical dyssynchrony in CRT patients. However, SDAT derived from standard 12-lead ECG would be clinically preferred.

Objective
To evaluate and compare the SDAT measured from BSM and 12-lead ECG for assessment of electrical resynchronization in patients with implanted CRT.

Methods
CRT patients with sinus rhythm and LBBB at baseline (n=19, 58% males; age 60±11 years; NYHA class II-III; QRS 160±29) were studied using 96-lead BSM. For each ECG lead, the activation time was automatically detected and SDAT was calculated using either 96 leads or standard 12 leads. Electrical dyssynchrony was assessed during native sinus rhythm and 6 different pacing modes (see figure).

Results
SDAT calculated from BSM and 12-lead ECG decreased during optimal BiV pacing as compared to sinus rhythm by 26% (p=0.006) and 30% (p=0.003), respectively. The two other BiV setups showed also a decrease in SDAT values. Importantly, a high degree of reliability was found between values of SDAT obtained from12-lead ECG and 96-lead BSM for different pacing modes, the intraclass correlation coefficient was 0.8 to 0.9 (95% CI 0.7 - 0.9, p&lt;0.001).

Conclusion
SDAT assessment is considered an important metric of electrical dyssynchrony in CRT. Our results suggest that 12-lead ECG provides similar results as BSM and thus, allows simplification of the measurement. Further prospective studies are necessary to verify the clinical utility of SDAT from 12-lead ECG.
Improvement in electrical synchrony during bi-ventricular vs. left ventricular pacing with dynamic atrioventricular delays may be predicted by conduction times
Authors: Thibault B , Chow A , Mangual J , Badie N , Waddingham P , Mcspadden LUKE , Betts T , Calo L , Grieco D , Leyva F 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Abbott

Introduction
Automatic adjustment of atrioventricular delay (AVD) with SyncAV has been shown to improve electrical synchrony with either biventricular (BiV) or left ventricular (LV) only pacing. Selecting the optimal pacing mode may be guided by measuring conduction delays between the right atrium (RA), right ventricle (RV), and LV.

Purpose
Evaluate correlations between inter-chamber conduction delays and the QRS duration (QRSd) reduction achieved by BiV or LV-only pacing with SyncAV.

Methods
CRT implant patients (LBBB, QRSd ≥ 150 ms) were prospectively enrolled. Blinded QRSd was measured from 12-lead ECG during BiV and LV-only pacing, with SyncAV enabled and optimized to minimize QRSd. Conduction delays were measured by the device from unipolar electrograms during pacing and sensing (e.g. RAp-RVs). Correlations between each delay and which mode had the narrower QRSd was assessed by binomial regression.

Results
In total, 68 patients were evaluated (66.1 yr, 67.1% male, 32.5% ischemic, 26.3% EF, 165.1 ms intrinsic QRSd). BiV+SyncAV and LV+SyncAV reduced QRSd by 23.8% and 21.3% (P&lt;0.001) vs. intrinsic conduction. Of all delays, RVs-LVs and LVp-RVs were significantly correlated with patient probability of BiV+SyncAV yielding a narrower QRSd than LV+SyncAV. BiV+SyncAV was favored in 70.6% (48/68) of all patients, but was favored in 92.3% (24/26) of patients with LVp-RVs &lt; median (143 ms) (P=0.030 vs all).

Conclusion
When combined with SyncAV, BiV yielded a narrower QRSd than LV-only in the majority of patients, but was favored in a greater proportion who exhibit LVp-RVs delays below the median. Such conduction delay cut-offs can be used to facilitate pacing mode selection.
Upgrade pacemaker to CRT: predictors and the importance of LVEF
Authors: Silva BV , Silverio Antonio P , Couto Pereira S , Alves Da Silva P , Brito J , Garcia B , Oliveira C , Martins AM , Nunes Ferreira A , Magalhaes A , Cristina H , J Pinto F , Sousa J , Marques P 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Nowadays 10-15% of CRT implantaon is upgrading from paents (pts) with pacemaker (PMK) who develop reduced LVEF and worsening symptoms from HF. There are few retrospecve studies showing some predictors of pts with single or dual chamber PMK that may need upgrade to CRT, but it is not completely established which pts may benefit the most.

Purpose
To identify predictors at follow-up of upgrading pacemaker to CRT in a population with pacemaker implantation.

Methods
Single center case-control study of pts that performed upgrading to CRT-pacemaker (CRT-P) in our hospital. We excluded pts that performed upgrade to CRT-D. We compare to a PMK populaon matched to age at implantaon and cause of PMK implantaon. Demographic, clinic and electrocardiographic (ECG) data were considered at baseline. Echocardiographic evaluation was performed before pacemaker/CRT upgrading implantaon and at follow-up. Predictors of upgrading were evaluated by the Cox regression. Prognosc impact of LVEF was evaluated as upgrading to CRT-P by Kaplan-Meier curves.

Results
We included 71 pts that performed CRT-P upgrade (mean age 77±10; 49,6% male, mean LVEF before PMK 54.9±9.2%) and 71 pts with pacemaker implantaon (mean age 78 ± 11; 50,4% male; mean LVEF 60.9±7.2%). The clinical characteriscs, ECG and echocardiographic were similar between pacemaker and CRT-P-upgrade, except atrial fibrillaon being more prevalent in PMK group (57.5% vs 42.5% p=0.039). Mortality was not different duringfollow-up between the two groups. In univariate analysis, QRS duraon (PMK: 115ms vs upgrade CRT-P: 132 ms, p=0.038), LVEF (PMK: 60.9% vs upgrade CRT-P: 54.9%, p=0.002) and LV end-diastolic diameter (LVEDD) (PMK: 48.9.4 ± 6.6mm vs upgrade CRT-P: 56.4 ± 6.6mm, p=0.001), LV end-sistolic diameter (LVESD) (PMK: 29.5 ± 6.5mm vs upgrade CRT-P: 37.9 ± 9 mm, p=0.006) were associate to upgrading to CRT. In our population, the unique independent predictor was lower LVEF(Long Rank 6.108, p=0.013) – Figure 1. The best LVEF cut- off to predict upgradingto CRT was 55% (AUC 0.954, sensitivity 64%, specificity 84%) – Figure 2.

Conclusion
In our populaon of CRT upgrading pts, a broad QRS duraon, lower LVEF and a higher LVEDD and LVESD were associated to upgrade to CTR-P. We try to establish a new value for LVEF that could lead to upgradingto CRT-P, and maybe the classical cut-off of 50% should be reviewed.
Systematic screening for right-to-left shunt prior to lead extraction
Authors: Breitenstein A , Hofer D , Starck CH , Steffel J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Transvenous lead extraction has become a relevant treatment option in patients with device-associated infection, but also in the context of device- and lead dysfunction. Lead extraction can be complicated by a stroke, which may result from paradoxical embolization of lead debrids during lead extraction in the presence of a patent foramen ovale (PFO) with a right-to-left shunt.

Purpose
Analysis of the presence of a PFO in patients undergoing transvenous lead extraction in a Swiss tertiary centre. Furthermore, different strategies to reduce the risk for stroke due to the presence of a PFO will be summarized.

Methods and Results
In this retrospective analysis from January 2017 until December 2021, a total of 304 patients who underwent lead extraction were included. In nearly half of the population, lead dysfunction was the leading cause for extraction, while device-associated infection was present in 31 % of the patients. In 14 patients (4.6 %), a right-to-left shunt was detected either during (via transesophageal echocardiography) or prior to the procedure. Prior to the systematic pre-procedural PFO screening, 9 patients with a right-to-left shunt were identified of which 2 patients suffered from a peri-interventional stroke (22 %) while in the population without a PFO no stroke occurred. The remaining 5 patients with a right-to-left shunt were identified prior to the lead extraction procedure (after setting up an institutional PFO screening programm) and were treated accordingly. Since then, no further neurological episodes occurred (Figure 1). If a PFO was identified, an interventional PFO occlusion was performed either prior to the lead extraction (2 of 5 patients) or together with the lead extraction as a single procedure (1 patient). In the 2 other patients, where a device infection was present together with a PFO, the PFO shunt was occluded transiently using a sizing balloon during the lead extraction procedure to avoid to implant a PFO occluder device in an infectious environment.

Conclusions
Presence of a right-to-left shunt in patients who need to undergo transvenous lead extraction is a known risk factor for embolic strokes. Identification and treatment of this condition prior or during lead extraction is associated with a reduction in stroke events.
Transvenous lead extraction: the Tandem approach
Authors: Akhtar Z , Zuberi Z , Leung LWM , Kontogiannis C , Waleed K , Elbatran AI , Sohal M , Gallagher MM 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Transvenous lead extraction (TLE) has become an important strategy in the management of patients with cardiac implantable electronic devices (CIEDs). A rising population of patients with CIEDs coupled with an expanding indication for TLE, has fuelled demand. There are notable procedural risks however development of techniques and tools have contributed to an improvement in the safety and efficacy of TLE. The mechanical rotational dissecting sheath is safe and efficacious whilst the Needle’s Eye Snare (NES) is an additional ‘bail-out’ strategy contributing to procedural success.

Purpose
We sought to evaluate the outcomes of TLE performed from the superior access in conjunction with counter-traction provided by snaring of the targeted lead via the femoral access.

Method
The ‘Tandem’ procedure consisted of the rotational powered sheath performing dissection of the adhesions encapsulating the leads (at the superior access), in ‘Tandem’ with the Needle’s Eye Snare providing countertraction via the femoral vein. In brief: after deployment of the locking stylet in the lead lumen, the NES was used to grasp the lead in the right atrium and hold it tort while a rotational sheath was used to dissect through the veins. Once the sheath reached the right atrium, the lead was released from the snare and the sheath was used to continue dissection toward the lead tip. Data for all consecutive ‘Tandem’ procedures performed between 1/1/2021 – 1/1/2022 in our high-volume TLE institute were collected and evaluated for safety and efficacy.

Results
Forty patients aged 69.2±16.3 (70% male), underwent TLE of 75 leads (45 right ventricle, 25, right atrium, 5 left ventricle) with dwell time of 150.1±80.3 months for a non-infectious indication (65%). Of the 40 cases, 27 were hypertensives, 14 had ischaemic heart disease whilst 5 suffered diabetes with a left ventricle ejection fraction of 46.8±10.2%; 12 (30%) were pacing dependent. Procedures were performed by cardiologists in the cardiac catheterisation suite under general anaesthesia (95%) using a locking stylet (100%) with an Evolution RL (11-french 58.7%); a NES 13 millimetres curve (88%) was used to successfully snare 91% of the targeted leads. Complete procedural success was achieved in 92% of leads with 98.7% clinical success. Minor complications occurred in 2 cases (pneumothorax, pocket haematoma requiring intervention), in the absence of any major complications or peri-procedural mortality; there was no 30-day mortality.

Conclusion
The ‘Tandem’ procedure provides an additional strategy to improve the safety and efficacy of TLE, especially in leads of a long dwell time.
Major procedure-related complications in a real-world cohort of patients undergoing transvenous lead extraction
Authors: Doring M , Lucas J , Bode K , Nedios S , Hilbert S , Ebert M , Moscoso Luduena C , Hindricks G , Richter S 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Transvenous lead extraction (TLE) is the mainstay therapy for device-related infections. Though TLE procedures are associated with low complication and high success rates, risk factors for major procedure-related complications remain not well defined.

Purpose
To evaluate the safety and efficacy of TLE in a large single centre cohort and to identify risk factors for major complications.

Methods
All consecutive patients undergoing TLE in our department between May 2012 and December 2021 were included in a prospective registry. Our protocol for TLE followed a stepwise approach according to lead dwell time and estimated complexity of the procedure: use of simple traction ± locking stylet (LS) ± mechanical and/or powered sheaths ± snare technique via a femoral or jugular access. Patient characteristics, procedural data and complications were gathered and analysed. Logistic regression analysis was applied to identify risk factors for major procedure related complications.

Results
A total of 2218 leads (25.7% ICD leads) were targeted for TLE in 1060 patients (67.7 ± 14.8 years; 74% male). The mean lead dwell time was 82 ± 62 months. The leading indication for TLE was cardiac device related infection (CDRI) in 695 patients (65.6%), 373 (35.2%) had systemic and 322 (30.4%) localized infection. Leads were extracted by simple traction in 30%, traction with LS in 3.7%, dilator sheaths with LS in 47.7%, and additional use of powered mechanical sheaths in 14.6%. The snare technique was used in 3.9%, with additional venous entry from femoral in 3.5% and jugular in 1.0% of all targeted leads. TLE was completely successful in 92.6%, partially successful with lead fragments &lt;4cm in 4.2%, and failed in 3.1% of all patients, which translated to a clinical success rate of 96.9%.
Twenty-nine patients (2.7%) experienced minor and 18 patients (1.7%) had major procedure-related complications (cardiac tamponade/perforation) including 2 intraprocedural deaths (0.2%). Presence of abandoned leads (HR 8.41, 95% CI 3.21–22.02; p&lt;0.001), lead-years-per-patient (HR 1.063, 95% CI 1.037–1.090; p&lt;0.001), dwelling time of the oldest lead (HR 1.011, 95% CI 1.006–1.016; p&lt;0.001), and a right-sided implantation (HR 2.68, 95% CI 1.05–6.83; p=0.04) were significant predictors of major complications in logistic regression analysis.

Conclusion
TLE is feasible, effective and safe in our large single centre experience. Overall complication and failure rates are low. Following our TLE protocol, the presence of abandoned leads, a right-sided implantation and dwelling time of the extracted leads were associated with major procedure-related complications.