bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiofrequency catheter ablation using QDOT MICRO: single-center experience in treating outflow tract premature ventricular complexes
Authors: Ciconte G , Salerno R , Negro G , Rondine R , Boccellino A , Napolano A , Maiolo V , Giannelli L , Sabatelli L , Calovic Z , Vicedomini G , Pappone C 
Published: May 2024

Abstract

Aims
This study sought to examine the efficacy of radiofrequency catheter ablation (RFCA) for premature ventricular complexes (PVCs) originating from the outflow tracts. The investigation utilized the QDOT MICRO™ (QDOT) catheter, known for enabling a temperature-controlled ablation strategy.

Methods and results
The study began in November 2022 at a single center. All patients (n=100, 57% male, mean age 49±18) were prospectively and consecutively enrolled and underwent PVCs ablation with QDOT-MICRO™ catheter. The procedural and efficacy data of the study population were compared with those of a control group composed of a cohort of 100 propensity score-matched patients who underwent the same procedure with the ThermoCool® SmartTouch® Catheter using the Ablation Index strategy. Acute procedural success was defined as the elimination of the targeted PVCs at the termination of the procedure. Clinical success was defined as at least an 80% decrease in PVCs burden. Follow-up visits with 24- to 48-h Holter monitoring were performed at baseline and 1, 3, and every 3 months thereafter. Both patients with follow-up &lt;6 months and non-outflow tracts PVCs were excluded. In the study cohort, the average PVCs burden was 21,13% (IQR: 12,50, 24,44) and the RVOT PVCs were 58% (n=58). The mean procedure and fluoroscopy times were 113±103 and 18±15, respectively, and significantly differ between both groups (p=0.02 and p&lt;0.001, respectively). Signals detected by the microelectrodes at the effective site of ablation differed significantly from those recorded by the standard bipolar electrodes (p&lt;0.001). No major complication occurred during the procedures, and there was no procedure-related mortality. The freedom from PVCs recurrences was 86% in the QDOT group and 84% in the STSF group.Freedom from PVCs recurrences at a mean follow-up of 11.5±1.6 months did not significantly differ between both groups (86% vs 84%, respectively; p=0.65).

Conclusion
This study suggests that RFCA using the QDOT MICRO™ catheter is not only effective but also comparable to the standard approach for treating outflow tract PVCs. Moreover, the study highlights shorter fluoroscopy and procedure times, reinforcing the catheter's efficiency and safety. The use of microelectrodes proved beneficial in enhancing precision in RF delivery.
Long-term outcomes associated with subcutaneous implantable cardioverter-defibrillators in patients with hypertrophic cardiomyopathy
Authors: Rella V , Maurizi N , Bernardini A , Brasca F M , Salerno S , Meda M , Mariani D , Torchio M , Conte G , Auricchio A , Parati G , Olivotto I , Perego G B , Cecchi F , Crotti L 
Published: May 2024

Abstract

Background
In patients with Hypertrophic Cardiomyopathy (HCM) S-ICD is usually the preferred option as pacing is generally not indicated. However, limited data are available on its current practice adoption and long term follow-up.

Purpose
The present study was designed to examine in a multicenter, open-label, long-term study, the patient’s selection process for S-ICD implantation, the short and long term complications, the appropriate shock (AS) rates, shock efficacy and outcome.

Methods
Consecutive HCM patients with an S-ICD implanted between 2013 and 2021 in 3 international centers were enrolled in this prospective observational study. Baseline, procedural and follow-up data together with clinical evaluation, ECG, echocardiography, and telemetry checks of the S-ICD were regularly collected.

Results
Seventy patients (64% males) were enrolled, implanted at 41±15 years, 62 (89%) in primary prevention with a mean ESC SCD risk score of 4,5±1.9%: 25 (40%) at low risk, 17 (27%) at intermediate and 20 (33%) at high risk. Patients were followed-up for 5.1±2.3 years (327 person-years). Notably, 25 (36%) were followed for more than 6 years up to 10 years. Two patients (3%) received an appropriate shock on ventricular fibrillation and 17 (24%) were diagnosed with a de-novo atrial fibrillation, sub-clinical in 6 (9%). One TIA and 2 strokes were reported. Inappropriate shocks occurred in 4 patients (6%), all before Smart-Pass algorithm implementation. Eight patients experienced device related adverse events (11%).

Conclusions
S-ICDs in HCM patients followed for over 5 years showed to be effective in the conversion of VF in 2 ESC SCD high risk patients (3%) and useful in the detection of sub-clinical AF in 6 (9%). S-ICDs are implanted in patients with an overall low-intermediate ESC SCD risk, probably reflecting both the inclusion of additional risk markers (i.e extensive LGE, reduced EF and apical aneurism) and the physician perception of low device-related complications S-ICD is generally safe, but greater scrutiny may be required to avoid overtreatment in HCM patients with milder risk profiles.Real world use and candidacy of S-ICDAppropriate and inappropriate shocks
Long-time exposure to sunlight is associated with the risk of sudden cardiac arrest and coronary heart disease
Authors: Kim M , Sung J H , Jang E S , Kim D H , You S C , Hwang K K , Bae J W , Kim D W , Yang P S , Joung B Y 
Published: May 2024

Abstract

Background
With ongoing climate change, the duration of sunshine hours will likely increase over the coming decades that escalating air temperature. Little is known about the potential cardiovascular risk from this climate factor.

Purpose
The aim of this study was to test whether duration of sunlight exposure is associated with incident sudden cardiac arrest (SCA), coronary heart disease (CHD), and hospitalization for heart failure (HF) and whether this association depends on seasonal variation.

Methods
A total of 308,851 participants from UK Biobank were included and were followed for a median time of 11.8 years. Participants reported how many hours they respectively spent the daylight outdoors on summer and winter typical days. Extreme outliers (&gt;12 hours/day in summer and &gt;8 hours/day in winter) were excluded. Average exposure time was calculated to unify the daylight outdoors time standard. Duration of sunlight exposure (average, summer, and winter) were categorized using quantiles and a restricted cubic spline for outcomes. Multivariate cox proportional hazard regression adjusted by age, sex, demographics, lifestyle, clinical and environmental factors was used for the analysis.

Results
During a follow-up, 1,572 (0.51%), 11,557 (3.74%) and 2,145 (0.68%) participants were diagnosed with SCA, CHD and hospitalization for HF. Compared with the participants exposed to short-time sunlight (average ≤ 1.5 hours/day), those who exposed to long-term sunlight (average ≥ 3.5 hours/day) had increased risk of SCA (HR 1.22, 95% CI 1.06 to 1.40) and CHD (HR 1.22, 95% CI 1.06 ~1.40). The associations between long-time exposure to sunlight and SCA were largely attributable to summer (HR 1.22, 95% CI 1.06 to 1.39) and not winter (HR 1.02, 95% CI 0.86 to 1.20), respectively. An hour increase of sunlight exposure was associated with increased risk of SCA in summer (HR, 1.03; 95% CI, 1.01 to 1.05), but not in winter (HR, 1.03, 95% CI, 0.99 to 1.06). Subgroup analysis identified that exposure to long-term sunlight was consistently increased risk of SCA, regardless of age, sex, body mass index, previous cardiovascular diseases, total physical activity, types of physical activity in last 4 weeks, use of sun/UV protection, sedentary time, natural environment percentage (buffer 1000m), and PM2.5. Finally, long-time exposure to sunlight was also associated with increased risk of CHD, but not associated with increased risk of HF hospitalization.

Conclusions
Findings from the present study indicate that daily long-time exposure to sunlight that increase in air temperature is a risk factor for SCA and CHD. These associations revealed graded relationship according to the duration of exposure to sunlight and more pronounced in summer. Our results suggest that public health efforts to reduce cardiovascular risk should take a wide range of exposure time to sunlight into account.
Impact of comorbidities on survival and complications in patients implanted with leadless pacemakers: a national, multicenter study
Authors: Oezkartal T , Conte G , Breitenstein A , Haeberlin A , Sticherling C , Ammann P , Grebmer C , D'alto A , Schoeni L , Bruno J , Bergonti M , Caputo M L , Klersy C , Auricchio A 
Published: May 2024

Abstract

Background
The number of leadless cardiac pacemaker (LCP) implantations has increased over the recent years, being more frequently performed in elderly patients with multiple comorbidities.

Purpose
The aim of this study is to analyze periprocedural complications and outcome of LCP patients according to their comorbidity status.

Methods
This is a Swiss multi-centre, retrospective cohort study including all consecutive patients implanted with a LCP (Medtronic Micra VR or AV) between 2015 and 2022. Charlson Comorbidity Index (CCI) was determined and patients were divided into two groups: CCI ≤ 5 (low comorbidity) and CCI &gt; 5 (high comorbidity). Periprocedural complications, in-hospital death, and all-cause mortality were assessed.

Results
A total of 863 patients (median age 81 years (IQR 76 – 86), male sex 65%) were included in the study, of which 58% had a CCI ≤ 5. Baseline characteristics of the 2 groups are summarized in the table. Patients in the high comorbidity group were older male presenting more frequently with ischemic cardiomyopathy, diabetes, chronic obstructive pulmonary disease, moderate to severe chronic kidney disease and malignancies. Urgent implantations were more frequent in the high comorbidity than in the low comorbidity group (65% vs. 50%, p&lt;0.001). Overall periprocedural complication rate was 2.9% (n = 25) without significant differences between the two groups (2.9% in both groups, p = 1.0). Pericardial effusion requiring pericardiocentesis was the most frequent periprocedural complication (n = 8, 0.9%). Median hospitalization was significantly longer (5 vs. 3 days, p&lt;0.001), and in-hospital mortality significantly higher (3.6% vs. 0.6%, p=0.002) in the high comorbidity group. None of the in-hospital deaths was deemed a periprocedural complication. Median follow-up was 15.4 months. As shown in the figure, all-cause mortality was significantly higher in the high morbidity group (HR 2.9, 95%-CI 2.2-3.8, p&lt;0.001) resulting in a mortality of 58% at 3 years.

Conclusions
LCP implantation in patients with multiple comorbidities was equally safe with similar peri-procedural complication rates as compared to patients with less comorbidities. However, both in-hospital death and all-cause mortality during follow-up were significantly higher in the high comorbidity group, because patients were older and sicker. Given that costs of LCPs are substantially higher than standard transvenous pacemakers, further studies are necessary to assess cost-effectiveness in patients with high comorbidity and reduced life expectancy.Figure - Survival estimate according CCITable - Baseline characteristics
The pacing threshold improvement of leadless pacemaker is better when mid or high right ventricular septal (RVS) approach than lower RVS approach after follow-up of 3 months
Authors: Kim D , Kim Y J , Jin M N , Park J B 
Published: May 2024

Abstract

Introduction
Leadless pacemaker procedures are rapidly increasing in last decade. Compared to conventional trans-venous pacemaker, pacing threshold of leadless pacemaker is important parameter for longevity (reference 1.). For the safety, right ventricular septum (RVS) is recommended as the pacing location. Recent study (reference 2.) showed that pacing thresholds in most leadless pacemaker implantation patients with elevated thresholds decrease after implant. Therefore, leadless pacemaker repositioning may not be necessary if the pacing threshold is ≤2 V. However, according to pacing location with mid-or above septum versus low or apical septum, pacing threshold stability and improvement during follow-up period after implantation is not clear.

Method
68 cases of leadless pacemaker implantation in 2 hospitals with 3 physicians was analysed. According to pacing location, we divided 2 groups with mid or above RVS and lower RVS. Patients with pacing location on mid or above RVS was 27 (Group A). Other patients with pacing location on lower RVS was 41 (Group B). During follow-up (mean 6 months), we analysed pacing threshold and QRS duration on electrocardiography (ECG) after implantation.

Results
Table 1. shows baseline characteristics including age, sex, and comorbidity were not different significantly between 2 groups. Only HF is lower in group A (14.8% versus 36.6%, p=0.044). Table 2. shows the comparison of 2 groups. Initial threshold of lower RV septal approach (Group B, 0.39±0.14V/0.24ms) showed better than mid or high septal approach (Group A, 0.70±0.33V/0.24ms), p &lt;0.001. However, 3 months later, pacing threshold decreased lower in Group A (mid or above RVS, 0.49±0.17V/0.50ms) than Group B (lower RVS, 0.67±0.50V/0.24ms), p &lt;0.001. Therefore, the change of pacing threshold is improved in Group A (mid or above RVS, -0.20±0.24V/0.24ms) than Group B (lower RVS, 0.28±0.51V/0.24ms), p &lt;0.001. However, other parameters including QRS duration and LVEF after implantation was not different between 2 groups.

Conclusion
The improvement of pacing threshold in mid or high RVS approach demonstrates that pacing threshold stability is more dominant than lower RVS approach. Our data shows that, after follow-up of 3 months, pacing threshold improvement of leadless pacemaker after implantation is better when mid or high RVS approach than lower RVS approach.Figure 1.Table 1. and 2.
Leadless pacemaker implantation versus conventional transvenous cardiac pacing early after transcatheter aortic valve replacement: a safe and relevant option?
Authors: Le Guily G , Rosier G , Vacher E , Poirier A , Le Page S , Ben Kilani M 
Published: May 2024

Abstract

Background
Leadless pacemakers (LPM) are known to have lower postoperative complications than conventional transvenous cardiac pacing especially in frail patients (pts) with many comorbidities.
The aim of this study was to assess the "real-life" feasibility and outcomes of LPMs compared to transvenous pacemakers (TPMs) in patients who underwent transcatheter aortic valve replacement (TAVR).

Methods
This is a retrospective single center study including all consecutive patients who received LPM or TPM (either single or double chamber) implantation early after a TAVR over a one-year period since September 2022 with a follow up period of at least 3 months.

Results
71 pts were included (mean age 82,56 ± 7,1 years old). 16 pts underwent LPM implantation (22,5%). Leadless system pacing was preferred in pts with history of active systemic infection 43,8%, complex conventional vascular approach 12,5 %, deterioration of general condition and clinical frailty 18,8% and history of breast cancer in 25 % pts.
Mean time between appearance of conductive disorders and pacemaker implantation was longer (2,9± 2,8 vs 1,5 ± 1,3 days; p=0,06) in the LPM group probably due to organizational issues. Procedure duration was significantly shorter in the LPM group (46 ±20,5 vs 69 ± 21,1 min; p = 0,01). There was no statistically significant difference in fluoroscopy time between the 2 groups even though this parameter was longer in the LPM group (6,8 min vs 5,6 min; p = 0,413). Significantly lower thresholds were observed in pts with LPM implantation (0,45 ± 0,33 vs 0,66 ± 0,25 V; p = 0,017) with no statistically significant difference between the 2 groups concerning the per-operative impedance value.
Median time from pacemaker implantation to discharge was 3,12 ± 3,26 vs 4,78 ±7,16 days after LPM and TPM implantation respectively (p = 0,195). There were less complications in the LPM group (1,4 % vs 9,9 %; p = 0,471). Complications were: arteriovenous fistula for 1 pt with LPM vs 2 pocket hematomas, 1 pneumothorax, 1 per-operative cardiac arrest and 3 leads dislodgements in pts with TPM. The mortality rate was significantly higher in the LPM group (4,2 % vs 2,8 %; p = 0,038) although no pacemaker related deaths were reported in both groups and no significant difference between the 2 groups was noted concerning rehospitalisations for cardiovascular cause (p= 0,407).

Conclusion
Early LPM implantation after TAVR is a feasible alternative to conventional pacing with significantly shorter procedure durations and better pacing thresholds. Our experience confirms the global clinical frailty of patients receiving LPM after TAVR but underlines the favorable safety profile of leadless system pacing with a low rate of complications.
Outcomes of tine-based leadless pacemakers retrieval: a multicenter study
Authors: Jurisic S , El-Chami M , Schiavone M , Gasperetti A , Tondo C , Gulletta S , Tandri H , Kowal J , Forleo G , Rovaris G , Saleh K , Steinwender C , Deharo J C , Hofer D , Breitenstein A 
Published: May 2024

Abstract

Background
Leadless cardiac pacemakers (LCP) are well established in daily practice and comparable in safety as well as efficacy to conventional transvenous pacemakers. With increasing implant volumes, more patients may need extraction and retrieval of these devices. Data on extractability of LCPs is however scare.

Purpose
The aim of this study is to analyze indication, techniques, efficacy and safety of LCP extractions in a multicenter international registry.

Methods
This is an international, multicenter retrospective registry. Demographic parameters, indication of LCP extraction, success and complication rate were analyzed.

Results
A total of 50 patients (median age 71 years (IQR 64-81), 34% female) were included in this study. 52% of patients received the LCP for complete AV block. The primary underlying cardiac condition was coronary artery disease in 42%. The main indication for LCP extraction was rise in threshold with loss of capture (32%), upgrade to biventricular pacemaker (26%) or upgrade to transvenous dual-chamber device (14%) (Figure 1). The overall success rate of device extraction was 96% with a mean dwell time of the LCP of 715 days (range 0-1477 days). In most cases, a steerable sheath with a single loop snare (71%) was used (Figure 2). Procedure related adverse events were low and included two pericardial effusion (not requiring any intervention) and one case of a device embolization that was retrieved successfully in the same setting. Overall mortality at 7 days was 0 %.

Conclusion
Retrieval/extraction of chronically implanted LCP appear to be safe and feasible in centers with expertise in femoral snaring.Indication for LCP retrievalTools used for LCP extraction
Precordial activation sequences from low frequency analysis in left bundle branch block patients: left bundle branch area pacing vs right ventricular pacing
Authors: Sales Belles C , Minchole A , Cabrera-Ramos M , Pueyo E , Ramos-Maqueda J 
Published: May 2024

Abstract

Introduction
Left bundle branch area pacing (LBBAP) provides a more synchronous and physiological ventricular activation than conventional right ventricular pacing (RVP) in LBBB patients. QRS duration (QRSd) is the standard measurement for assessing depolarization synchrony, but it only provides information about the activation time and not about the activation sequence.

Purpose
Our aim is to assess the activation sequence by precordial activation delay (pAD) using a low-frequency (LF) ECG method comparing baseline and paced ECG in LBBAP and RVP patients.

Methods
Twelve-lead ECGs recordings were acquired from 29 patients with LBBB (16 LBBAP and 13 RVP) after 24 hours of sequential LBBAP or RVP. LF-ECG was employed for QRS-complex analysis. The activation time for each lead was computed and an activation sequence constructed by linking them. pAD was calculated as the time between the first and the last lead activation. pAD provides information about both, the delay in ventricular depolarization as indicated by its magnitude, and the depolarization direction (as it can take a positive or negative value indicating a left or right ventricle delay, respectively).

Results
At baseline, both groups (LBBAP and RVP) showed the latest activation at V5-V6, supported by positive median pAD values with no statistically significant differences between both groups (50 (21, 65) vs. 54 (17, 67) ms, p=0.93). LBBAP reduced V6 delay and pAD values compared to the baseline QRS (basal: 50 (21, 65) vs. paced: 2 (-18, 25) ms, p&lt;0.001) while RVP did not exhibit any difference (basal: 54 (17, 67) vs. paced: 36 (19, 53) ms, p=0.33). LBBAP provided lower pAD values when compared to RVP (2 (-18, 25) vs. 36 (19, 53) ms, p&lt;0.01).

Conclusions
pAD measured using a LF-ECG analysis is a feasible method to evaluate depolarization synchrony and provides complementary information to QRSd. In contrast to RVP, LBBAP generates a physiological ventricular activation sequence in patients with LBBB.Baseline patients characteristicsVentricular activation sequences and pAD
The role of atrial pacing site in reducing filling pressures by accelerated pacing in virtual HFpEF patients
Authors: Van Loon T , Habel N , Van Empel V , Linz D , Delhaas T , Lustgarten D , Vernooy K , Meyer M , Lumens J 
Published: May 2024

Abstract

Background
Patients with heart failure with preserved ejection fraction (HFpEF) and pacemakers have been shown to benefit from moderately accelerated pacing rates compared to the standard 60bpm. HFpEF patients often present with prolonged P-wave duration (PWD) and atrial fibrillation. Right atrial appendage pacing (RAAP) lengthens PWD, RA septal (RASP) has a neutral effect, while Bachmann’s bundle pacing (BBP) normalizes or shortens PWD compared to sinus rhythm. The mechanical and hemodynamic effects of atrial pacing site selection remain unknown.

Aim
To investigate the impact of RAAP, RASP and BBP on cardiac mechanics and hemodynamics in an established cohort of virtual HFpEF patients undergoing accelerated pacing.

Method
HFpEF with prolonged PWD was simulated using the validated CircAdapt computational model of the human cardiovascular system. First, left ventricular (LV) diastolic dysfunction was simulated by decreasing LV myocardial relaxation rate and compliance, such that mean left atrial (LA) pressure (mLAP) was 15mmHg. Second, PWD was prolonged by prescribing a gradual electrical activation delay from RA to LA of 140ms. We then simulated atrial pacing with three different lead positions (Fig.1, left) and gradually increased pacing rate with a constant 120-ms paced atrioventricular (AV) delay. The CircAdapt model computed regional LA strain and mLAP with RAAP, RASP, and BBP. Cardiac output (5L/min) and mean arterial pressure (92mmHg) were kept constant in all simulations.

Results
Simulated BBP demonstrated the most synchronous LA mechanical activation and function, characterized by uniform segmental LA strain patterns and highest LA reservoir strain (LASR) (Fig.1, middle, with colored arrows highlighting the mechanical dyssynchrony). Hemodynamically (Fig.1, right), BBP acutely decreased mLAP (-1.0mmHg) at the initial heart rate of 60bpm, while RAAP increased it (+0.3mmHg). As pacing rate accelerated, BBP reduces filling pressure (mLAP: -2.8mmHg), more than RASP (-1.8mmHg) or RAAP (-1.2mmHg) at 80bpm. At high pacing rates, RASP and RAAP adversely increase mLAP, due to the prolonged atrial contraction duration and shorter LV filling time.

Conclusion
Our simulations of different atrial pacing sites in virtual HFpEF patients suggest that BBP yields the most synchronous LA activation pattern and a more substantial reduction in filling pressures with accelerated atrial pacing compared to RASP. Reduction in mLAP with accelerated pacing was attenuated with RAAP. While our study concentrated on a specific paced AV interval, the favorable outcomes observed with BBP could be further improved by including different, rate-adaptive, AV protocols.Fig 1.