bluuebunny/crossref_metadata_2025_split huggingface dataset:
Safety and efficacy of intra-coronary chilled saline infusion during epicardial ablation in the left ventricular summit
Authors: Banavalikar B , Shenthar J , Krishnappa D , Padmanabhan D , Reddy S 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The left ventricular (LV) summit is the most common epicardial site of idiopathic premature ventricular complexes (PVC) and is frequently associated with PVC-induced cardiomyopathy. Catheter ablation in the LV summit can be challenging due to its proximity with the major coronaries.
Hypothesis: Infusion of chilled saline (5-10 degree Celsius) into the left main coronary artery cools the endothelium during epicardial ablation in the LV summit and therefore, protects the coronaries from thermal damage.

Purpose
To determine the safety and efficacy of intra-coronary chilled saline infusion during epicardial ablation in the LV summit.

Methods
Patients with symptomatic idiopathic PVC from the LV summit formed the study population. Those with significant coronary artery disease (coronary stenosis &gt;50%) or with a scar on cardiac MRI were excluded from the study. Irrigated ablation was performed in the epicardium either percutaneously or transvenously via the distal great cardiac vein (GCV). A coronary angiogram (CAG) was always performed before RF ablation (RFA) to delineate the distance of the ablation catheter from the proximal coronaries. Chilled saline (5-10 degree Celsius) was administered into the left main coronary artery (LMCA) via Judkins catheter at a constant rate of 50 ml/min throughout the entire duration of ablation. Post-RFA, CAG was repeated to exclude any damage to the coronary arteries.

Results
Between January 2020 and July 2022, 37 patients (mean age 47.2±11.6 years; 16 females) underwent epicardial ablation in the LV summit accompanied by intra-coronary chilled saline infusion. The mean LV ejection fraction was 46.6±7.9%, and 15 patients had LVEF &lt;50% (PVC-induced cardiomyopathy). Epicardial ablation was performed percutaneously in six patients, whereas in 21 patients, it was done transvenously in the distal GCV. Chilled saline was infused into the LMCA during the entire duration of RFA without any untoward effect in any of the patients. Acute procedural success (complete elimination of the clinical PVC) was achieved in 34 out of the 37 patients. At a mean follow-up of 17±7.9 months, 35 patients (91.8%) were asymptomatic and free from the clinical arrhythmia.

Conclusion
Intra-coronary chilled saline administered during epicardial ablation in the LV summit is safe and effective in preventing RF-induced thermal injury to the proximal coronary arteries.
Stereotactic arrhythmia radiotherapy for ventricular tachycardia does not appear to alter QRS duration and QTc interval: a secondary analysis of the prospective STARNL-1 trial
Authors: Hoeksema W F , Van Der Ree M H , Dieleman E M T , Visser J , Planken R N , De Bruin-Bon R H A , De Jong R M A J , Kemme M J B , Balt J C , Balgobind B V , Postema P G 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Dutch Heart Foundation grant to dr. P.G. Postema, MD PhD

Background
Stereotactic arrhythmia radiotherapy (STAR) has evolved as promising bail-out treatment in patients with therapy-refractory ventricular tachycardia (VT). The mechanism of action of STAR in preventing VT has yet to be elucidated and further understanding could improve this technique in the future. Preclinical studies reported an increase in conduction velocity and consequently a decrease in conduction intervals on electrocardiograms (ECGs) within the first months after STAR, although this has not yet been evaluated in detail in prospective studies.

Purpose
To evaluate the early effects of STAR on ventricular conduction as electrocardiographically assessed.

Methods
The STARNL-1 was a prospective, monocenter, pre-post intervention study. Six patients with VT recurrences despite optimal doses of anti-arrhythmic drugs (AADs), after one or more unsuccessful catheter ablation(s), were considered therapy-refractory. Patients were treated with a single fraction of 25 Gy. ECG evaluation included ECGs recorded pre-therapy, at 3 hours, 12 hours, 24 hours, 1 month, and 3 months after therapy. For an additional assessment, only patients in whom AADs remained unchanged up to 3 months after STAR were selected. QRS duration and QT interval were measured by a single observer using digital callipers. Four consecutive beats were used to measure and calculate a mean QRS duration and QT interval per ECG. This study was not powered to evaluate for significant changes in ECG parameters.

Results
All patients were male, all suffered from ischaemic cardiomyopathy, and all completed 3-month follow-up. One patient presented with atrial fibrillation on ECG recordings, and three patients with a paced rhythm. Four patients (66.7%) were selected for an additional assessment, two patients (P1 and P2, 33.3%) underwent changes in AAD dose and were therefore excluded. Figure 1 shows a line graph of the QRS duration and QTc interval of all STARNL-1 patients during 3-month follow-up. As can be appreciated from Figure 1, QRS duration and QTc interval did not appear to be altered between pre-therapy and 3 months after therapy. When excluding P1 and P2, QRS duration and QTc interval also did not appear to be altered between pre-therapy and 3 months after therapy.

Conclusion(s)
STAR for VT does not appear to alter QRS duration and QTc interval within the first 3 months after therapy.
QRS complex and T wave planarity for the prediction of death and appropriate shocks in recipients of prophylactic implantable defibrillators
Authors: Novotny T , Hnatkova K , Andrsova I , Vandenberk B , Sprenkeler D J , Junttila J , Reichlin T , Schloegl S , Friede T , Bauer A , Willems R , Schmidt G , Sticherling C , Zabel M , Malik M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Community’s 7th Framework Programme (HEALTH-F2-2009-602299) Ministry of Health, Czech Republic

Background
Three-dimensional (e.g., vectorcardiography) loops of normal physiologic QRS complex and T wave are known to be planar. Non-planarity of these electrocardiogram (ECG) loops was described in cardiac patients, mainly in relation to ischemic heart disease, but predictive values of the extent of non-planarity of the loops have not been systematically researched.

Methods
Pre-implantation digital ECGs were collected in 1948 cardiac patients (381 females, median age 65, inter-quartile range 56 – 72 years, 62% ischemic heart disease) who obtained an implantable cardioverter-defibrillator (ICD) for primary prophylactic reasons. In each ECG, QRS and T wave 3-dimensional loops were constructed using singular value decomposition and the non-planarity of the loops was measured as the relative power of the 3rd, least significant decomposition component. The non-planarity (i.e., the spatial twist) of the loops was related to all-cause mortality and to appropriate ICD shocks that occurred during the first 5 years after device implantation. This predictive power was compared to that of age, heart rate, left ventricular ejection fraction, QRS duration, spatial QRS-T angle, QTc interval, and T-peak to T-end interval.

Results
Non-planarity of the QRS loop was significantly associated with follow-up deaths despite ICD protection (p&lt;0.001 both univariably and in multivariable Cox regression analysis) but was less powerfully associated with appropriate ICD shocks. Non-planarity of the T wave loop was significantly associated with appropriate ICD shocks during follow-up (p&lt;0.001 both univariably and in multivariable Cox regression analysis) but was not associated with mortality during follow-up (Table). This was also seen in significant separation of Kaplan-Meier event probability curves (Figure).

Conclusions
The analysed data of recipients of prophylactic ICDs suggest that non-planarity of QRS complex and T wave loops offers distinction between patients who are at greater risk of death despite ICD protection and those who are likely to utilize the defibrillator protection.
Relation between recovering right ventricular function and appropriate ICD Therapy
Authors: Chiba T , Kajiyama T , Komai Y , Takanashi Y , Yoshino Y , Ryuzaki S , Kitagawa M , Ito R , Nakano M , Nakano M , Kondo Y , Kobayashi Y 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Right ventricular fractional area change (RVFAC) as right ventricular function is recently referred as an independent predictor of sudden cardiac death (SCD). Light ventricular function is related with SCD and adopted as a criteria of ICD implantation for primary prophylaxis. The purpose of this study was to evaluate the association of RVFAC and appropriate ICD therapy.

Methods
Consecutive patients who underwent initial ICD implantation for any diseases except for hypertrophic cardiomyopathy and Brugada syndrome and long QT syndrome were retrospectively enrolled from 2012 to 2018. Transthoracic echocardiographic parameters before ICD implantation were evaluated to investigate the association with appropriate ICD therapy. We analyzed RV function of patients undergoing echocardiography one year after implantation. RVFAC was measured by one physician and one echocardiologist.

Results
In total, 172 patients (60.3±13.6 years, 131 males) including 63 ischemic cardiomyopathy were enrolled. Ninety patients received an ICD as a secondary prophylaxis. Mean LVEF and RVFAC were 38.3±14.3% and 35.8±8.82%, respectively. There was no correlation between RVFAC and LVEF (correlation coefficient =0.274). Regarding appropriate ICD therapy events, the best cut-off value of RVFAC was 34.8%. The odds ratio of low RVFAC was 2.731 (95%CI: 1.456-5.121, P&lt;0.001, Fig.1). Secondary prophylactic cohort with low RVFAC significantly showed highest incidence of appropriate ICD therapy. In multivariate analysis, only low RVFAC was an independent predictor of appropriate ICD therapy (hazard ratio 3.53, 95%CI:1.78- 6.99, P&lt;0.001). Among patients with RV dysfunction, RVFAC was normalized in 39% patients during follow up. This recovered group showed significantly lower incidence of appropriate ICD therapy than non-recovered group (P=0.037). In multivariate analysis, recovered RVFAC was related to decrease of appropriate ICD therapy rather than recovered LVEF. In patents without LV dysfunction, recovered RVFAC was significantly associated with lower incidence of ICD therapy (P=0.023, Fig.2)

Conclusion
RVFAC and RV function improvement may be important to stratify the prognosis of ICD patients.
Zero or near-zero x-ray pacemaker implantation in paediatric patients. dream or reality?
Authors: Silvetti M S , Pazzano V , Battipaglia I , Saputo F A , Tamburri I , Campisi M , Battista V , Silvetti G , Drago F 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background/Introduction
Transvenous implantation of pacemaker is performed with fluoroscopy for leads’ insertion and implantation in the heart. This implies radiation exposure for patients and operators. Fluoroscopy allows a two-dimensional view of lead movements, and sometimes it is difficult to implant lead in the complex heart anatomy, or in alternative right ventricular (RV) pacing sites, that often requires higher radiation doses. These alternative pacing sites may prevent pacing-induced ventricular dysfunction. They are his bundle pacing area (HBP), ventricular septum close to the conduction system area (VS), RV outflow tract (RVOT). The use of three-dimensional-electroanatomic mapping system (3D-EAM) may reduce fluoroscopy and guide lead implantation. Published median fluoroscopy data for similar procedure are: 6 mGy (1), 13 mGy and 231 microGy/m2 (2).

Purpose
of this study is to seek out if a 3D-EAM-guided transvenous implantation into RV alternative sites pacing in paediatric patients can be accomplished with zero or near-zero X-rays.

Methods
Retrospective analysis of children and adolescents with congenital or acquired (idiopathic) complete atrioventricular block (CAVB) without other congenital heart defects who underwent 3D-EAM-guided pacing in alternative RV sites. The implant procedure was divided in 4 steps: 1-contrast venography; 2- 3D mapping: with a steerable catheter (femoral vein), the 3D-EAM acquired geometric reconstruction of the right heart and a pacing map identified RV sites with narrower paced QRS; 3-axillary vein puncture; 4-lead and pacemaker implantation: 3D-EAM guided stylet-directed screw-in lead implantation toward desired RV sites. Data are reported as median (25th-75th centiles).

Results
54 CAVB patients (42 females), underwent 3D EAM-guided pacing (27 VVIR, 27 DDD) at age 11.5 (7.7-14) years, weight 42 (26-54) kg. Pacing sites were: 10 HBP, 4 RVOT, 40 VS (Figure 1). Procedure time was 170 (143-193) min, total fluoroscopy exposure and that of the 4 steps are reported in Table 1. The lowest exposures were: 0.2 mGy, 8 microGy/m2 (VVIR) and 0.6 mGy, 15 microGy/m2 (DDD). Paced QRS was 115 (100-120) ms.

Conclusions
3D-EAM-guided alternative RV pacing sites was accomplished with very low fluoroscopic exposure, close to zero in some cases. Therefore, with 3D-EAM we can significantly reduce radiological doses also in difficult pacing procedures in paediatric patients, thus reducing radiological risks and preserving ventricular function. The dream is becoming reality.
Safety and efficacy of automatic capture threshold algorithms in left bundle branch area pacing
Authors: Ghiglieno C , Dell'era G , Veroli A , D'amico A , De Vecchi F , Porcellini S , Santagostino M , Patti G 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Automatic capture algorithms periodically measure the minimal quantity of current needed for pacing, self-adjusting output to guarantee consistent myocardial capture, enhancing patient safety in case of an unexpected rise in threshold and reducing current drain. Left bundle branch area pacing (LBBAP) is an emerging conduction system pacing (CSP) technique which overcomes technical issues and weaknesses of pure Hisian pacing.

Purpose
The aim of our study was to evaluate safety and efficacy of automatic threshold algorithms in a population of patients with LBBAP.

Methods
We prospectively enrolled patients receiving LBBAP with different companies which provide LBBAP material) and we evaluated automatic capture threshold algorithms safety and accuracy at 24 hours and at 3 months after implantation. Moreover, when available, home monitoring was used for follow up.

Results
We included 45 consecutive patients who underwent LBBAP from January 2022 to August 2022. At 24 hours, mean manual LBBAP threshold was 0.5±0.2 V at 0.4 msec, while automatic LBBAP threshold was 0.5±0.3 V at 0.4 msec (p = 0.30). At 3 months mean manual LBBAP threshold was 0.6±0.2V at 0.4 msec vs 0.6±0.2V at 0.4 msec (p = 0.25). Sensing and impedance measures where optimal at 24 hours and improved during 3 months follow up, respectively from 13.7±4.8 mV to 13.9±4.8 mV (p = 0.6) and from 460.1±130 Ohm to 417.1±96.2 Ohm (p = 0.1).

Conclusion
Automatic threshold algorithms are able to effectively measure LBBAP capture threshold both in the acute phase and during follow up. The possibility to safely use automatic threshold algorithms, thus preserving battery and protecting patients against possible future threshold rises, represents another advantage of LBBAP.
Lowest peak central venous pressure correlates with highest invasive arterial blood pressure as a method for optimising AV delay in post-surgical temporary pacing
Authors: Tindale A , Cretu I , Meng H , Mason M J , Francis D P 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): British Heart Foundation.

Background
Atrioventricular (AV) delay optimisation has been performed using a variety of methods, including doppler outflow and alternating blood pressure algorithms. Patients after cardiac surgery are usually invasively monitored with arterial and central venous pressure (CVP) lines.

Purpose
We aimed to see if the CVP line could be used to optimise AV delays in temporary pacing for situations where the arterial line is absent or non-functional.

Methods
11 patients in sinus rhythm but with temporary pacemakers after cardiac surgery were studied. Each patient underwent alternating optimisation algorithms where they were subjected to 8 transitions between a reference AV delay of 120ms and a tested AV delay ranging from 40ms to 280 ms. Testing was terminated after the AV delay occurred when native conduction occurred i.e after they began AAI pacing. All patients were paced at 80 bpm.
Arterial blood pressure (ABP) and CVP were recorded from radial arterial lines and central venous lines in the internal jugular vein during the transitions. The optimal point was defined as the AV delay generating the maximum systolic blood pressure. The CVP was measured in 3 ways: peak pressure, mean pressure, and area under the curve. Central venous pressure tracings were corrected for respiration using a "fit-a-curve" function. All analysis was performed in Python.

Results
Individual pressure readings.
There was a negative correlation between individual ABP and Peak CVP pressure readings (R= -0.539, p=0&lt;0.001). A representative example for a single patient is shown in Figure 1 and for all data in Figure 2. A similar relationship, albeit less strong, was seen between ABP and Mean CVP (R= -0.281, p=0.046). There was no significant relationship between ABP and CVP AUC (R = -0.281, p=0.130).
Optimum pressure settings:
There was a strong correlation between the optimum AV delay as defined by the highest ABP and the optimum AVD as defined by the lowest peak CVP (R = 0.672, p=0.03). There was no significant relationship between the optimum AVD delay as defined by peak ABP and the optimum AVD defined by either mean CVP nor CVP AUC (R=0.269, p=0.452 for both).

Conclusions
There is an inverse relationship between individual measurements of arterial blood pressure and both peak and mean central venous pressure. The optimal AVD as defined by the highest ABP correlates with the optimal AVD as defined by the lowest peak CVP measurement. However, this method does require correction for respiratory artefact.
Electrocardiographic predictors of atrial mechanical sensing in patients with leadless VDD pacemakers
Authors: Hofer D , Perucchini F , Zehetleitner S , Saguner A , Haeberlin A , Steffel J , Breitenstein A 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Leadless pacemakers (LP) capable of VDD function are a cornerstone of modern pacemaker therapy reducing complications in elderly patients while enabling atrioventricular synchrony through mechanical sensing of atrial contraction. Because mechanical sensing is less reliable than electrical sensing, the reliability of VDD function in LP varies. We evaluated the p-wave amplitude from patient ECGs as a predictor for successful VDD function in LP.

Materials and methods
Consecutive patients undergoing LP implantation capable of VDD function were included in this multi-center retrospective cohort study. As VDD function is mainly dependent on the A4 signal amplitude in the current generation of the device, ECG parameters pre-implantation were evaluated separately and in combination for association with A4 signal amplitude post-implantation.

Results
122 Patients (mean age 81, female 44%, mean BMI 25.9 kg/m2) were included. Main indication for LP implantation was AV-Block (70%). BMI-adjusted P-wave amplitude demonstrated a statistically significant positive correlation with A4 signal amplitude in leads I, II, aVL, aVF, aVR, V1 and V2 (all p&lt;0.05). A p-wave amplitude of at least 0.1mV had a specificity of 72% (95%-CI 50%-89%) for a good A4 signal. A sum of at least 0.2mV of p-wave amplitudes in V1 and aVL predicts a specificity of 83% (95%-CI 67-100%) for a good A4 signal.

Conclusions
P-wave amplitudes in selected ECG leads can predict A4 signal amplitude and therefore the reliability of VDD function in LP.
Usefulness of parahisian pacing for risk prediction of pacemaker implantation after TAVI
Authors: Notarangelo M , Dinatale A , Crocamo A , Vrenozaj R , Bearzot L , Gonzi G , Guidorossi A , Tadonio I , Vignali L , Niccoli G , Ardissino D 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Conduction disturbances determining pacemaker implantation are a significant concern in patients undergoing Transcatheter Aortic Valve Implantation (TAVI), a procedure that is nowadays spreading even in the low-risk population.

OBJECTIVE
The aim of the study was to evaluate the role of the parahisian pacing, a method to directly identify the conduction system anatomical variability, in predicting the iatrogenic damage risk conditioning pacemaker implantation after TAVI.

Methods
Between October 2021 and November 2022 we prospectively collected clinical features, ECG, procedural and imaging data (cardiac CT and echocardiography) of every patient who underwent electrophysiological study for pre-existing or worsening conduction disorders within 48 hours after TAVI procedures in our centre. After having recorded the HV interval, parahisian stimulation at decreasing energy output was performed (CL 600 ms, 25V to 0.5V x 2 ms) with definition of the loss of capture pattern related to the three anatomical variations of His bundle described by Kawashima (1).
Fisher’s exact test was used for statistical analysis; p-value &lt;0.05 was considered statistically significant.

Results
Out of 110 TAVI performed, a total of 31 patients with conduction disorders have been studied. Patients who developed permanent 3rd degree AV block after the procedure were excluded. Mean age was 82.6±4.4 years; 21 patients (67.7%) were males. 11 patients (35.5%) had a pre-existing conduction disorder worsened after TAVI, 13 patients (41.9%) developed newly-onset LBBB; 8 (25.8%) also developed 1st degree AV block. The total number of patients who underwent PM implantation was 16 (51.6%). The anatomical variables (membranous septum &lt;3mm and/or septal cusps calcifications) and type of valve implanted were not significantly associated with PM implantation (p = NS). An HV interval &lt;70 ms was registered in 20 (64.5%) patients (Fig. 1); 7 of them underwent PM implantation as they developed paroxysmal 3rd degree AV block. These 7 patients all had type 2 or type 3 pattern during parahisian stimulation. None of the patients undergoing PM implantation presented a type 1 pattern during parahisian stimulation. A significant protective value (p = 0.02) for PM implantation in patients with type 1 pattern was observed (Fig. 2).

Conclusions
Parahisian stimulation can be a useful tool to define the conduction system anatomical variability. It can also be helpful to predict the conduction system damage risk during TAVI, conditioning PM implantation. Our data need to be confirmed in a larger population.