bluuebunny/crossref_metadata_2025 huggingface dataset:
P351Therapeutic inefficacy and pro-arrhythmic nature of metoprolol succinate and carvedilol therapy in patients with idiopathic, frequent, monomorphic premature ventricular contractions
Authors: Turan O E , Hasdemir C
Published: June 2020

Funding Acknowledgements

None

Background

Anti-arrhythmic drugs remain the first-line therapy for treatment of idiopathic ventricular arrhythmias in clinical practice.

Purpose

The aim of this study was to assess the therapeutic efficacy of extended-release metoprolol succinate (MetS) and carvedilol for idiopathic, frequent, monomorphic premature ventricular contractions (PVCs).

Methods

Study population consisted of 115 consecutive patients: 72 received MetS and 43 received carvedilol.  All patients underwent 24-hour Holter monitoring at baseline and during drug therapy.  PVC burden response to drug therapy was categorized as "Good" (≥80% reduction), "Poor" (either < 80% reduction or ≤ 50% increase) and "Pro-arrhythmic" response (> 50% increase) based on change in PVC burden compared to baseline.

Results

Presenting symptoms were palpitations in 69 (60%), shortness of breath/chest pain/syncope in 12 (10.5%), and coincidentally discovered in 34 (29.5%) patients.  Mean MetS and carvedilol dosages were 65.57 ± 30.67 mg/day and 23.66 ± 4.26 mg/day, respectively.  "Good", "Poor" and "Pro-arrhythmic" response was observed in 13.9% and 23.3%, 61.1% and 60.5%, and 25% and 16.2% of patients treated with MetS and carvedilol, respectively.  In patients with relatively high (≥16%) PVC burden, "Poor" response was observed in 86.9% and 76% of patients treated with MetS and carvedilol, respectively.  Side-effects and/or intolerance were observed in 5.5 % and 13.9 % of patients treated with MetS and carvedilol, respectively.

Conclusions

MetS and carvedilol for idiopathic, frequent, monomorphic PVCs is frequently inefficient.  Therapeutic efficacy decreases further in patients with relatively high (≥16%) PVC burden.  "Pro-arrhythmic" response was observed in approximately one quarter of the patients.

All patients Metoprolol Succinate (n = 71) Carvedilol (n = 43) p value Good response,n (%) 7 (9.9) 7 (16.3) 0.38 Poor response,n (%) 46 (64.8) 29 (67.4) 0.38 Pro-arrhythmic response,n (%) 18 (25.4) 7 (16.3) 0.38 Patients with PVC burden≥%16 Metoprolol Succinate (n = 22) Carvedilol (n = 25) Good response,n (%) 1 (4.5) 3 (12) 0.56 Poor response,n (%) 20 (91) 20 (80) 0.56 Pro-arrhythmic response,n (%) 1 (4.5) 2 (8) 0.56 Therapeutic response to Metoprolol Succinate and Carvedilol
P1487Cardiac resynchronization through His bundle pacing in patients with heart failure
Authors: Moraleda Salas M T , Sigismondi A , Arce Leon A , Fernandez Gomez J M , Manovel Sanchez A , Venegas Gamero J , Morina Vazquez P
Published: June 2020

Introduction and purpose

Permanent His bundle pacing (p-HBP) can correct intraventricular conduction disorders and could be a physiological alternative for traditional cardiac resynchronization therapy (CRT) via the coronary sinus: our aim was to describe our results in patients with heart failure and ventricular dysfunction who were resynchronized by p-HBP.

Methods

Prospective descriptive study of patients with CRT indication and who were resynchronized by p-HBP, using the specific tools. The correction of bundle branch block (BBB) by His bundle pacing (HBP) has been previously checked. We analyzed: the global success of the implant, the His thresholds, and the improvement in left ventricular ejection fraction (LVEF) at one month of follow-up.

Results

We included 54 patients (median age 66 (56-72)) with an indication for CRT: 89% (n = 48) with heart failure (HF), left bundle block branch (LBBB) and LVEF <35%; 3% (n = 2) with HF, right bundle block branch (RBBB) and LVEF <35%; 2% (n = 1) with permanent pacemaker, ventricular dysfunction and ventricular pacing >40%; and 6 % (n = 3) with complete AV block, LBBB and ventricular dysfunction. With HBP we corrected the BBB in 83% of patients (n = 45), and we achieved cardiac resynchronization through p-HBP in 93% of this patients (n = 42), with a global success (including those in whom HBP did not correct the BBB) of 78% (n = 42).

The basal QRS was 160 ms (151-162) and the paced QRS was 132 ms (125-145). The median of His acute threshold was 1.6 volts (0.9-1.9), stable at one month of follow-up, excluding one patient whose His threshold progressively increased to 5.5 volts. There was no dislocation of leads in the follow-up. LVEF improved in all patients: basal 30% (27-35) and at one month follow-up 52% (48-64). Median fluoroscopy times of device implantation including the time taken for temporary HBP were 8.1 minutes (range 6.1-9.9). There were no relevant complications during the implant or follow-up; all patients showed clinical subjective improvement.

Conclusions

CRT by p-HBP is feasible and safe in a high percentage of patients, with reasonable times of fluoroscopy, acceptable capture thresholds, and an early improvement in LVEF in patients with HF and an indication for CRT.
1269The SADS heart of the matter: a review of the sudden arrhythmic death syndrome (SADS) biobank - the cornerstone of a national strategy
Authors: Carron J , O"brien J , Heverin K , Gallagher M , Fitzgibbon M , Fabre A , Mcgorrian C , Galvin J
Published: June 2020

Background

Sudden cardiac death (SCD) in the young (age 1-35) is commonly attributed to structural and arrhythmogenic syndromes, for which there is often an underlying genetic basis. Expert recommendation emphasises the importance of genetic testing in such cases, however to date this remains the first and only national programme in Europe to facilitate this. 

Aim

 To review detection rates of genetic variants in samples tested via the SADS BioBank and possibly demonstrate the merits of this novel resource for primary prevention for family members.

Methods

 Family screening and consent for genetic testing was carried out in the Family Heart Screening Clinic. Result analysis of samples sent for molecular autopsy via the BioBank from its induction in January 2015 was performed. Genetic analysis was conducted via the same internationally accredited next generation sequencing lab.

Results

 From January 2015 to July 2019, 161 samples had been stored in the SADS BioBank following confirmed SADS death on autopsy; 33% female and 67% male. Of these, 24 (14.9%) samples were sent for genetic testing: 21 for a 380 gene molecular autopsy and 3 for a targeted hypertrophic cardiomyopathy panel (173 genes). Of 24 samples tested, 10 (42%) yielded positive genetic variants: 4 American College of Medical Genetics (ACMG) Class IV or V mutations considered pathogenic, and 6 ACMG class III variants of uncertain significance (VUS). Familial cascade screening following confirmed pathogenic mutations resulted in detection of 3 (33.3%) positive genotypes in 9 first-degree relatives. Screening of relatives of Class III positive probands resulted in diagnosis of an Inherited Cardiac Condition (ICC) in 25% of first-degree relatives. 8.2% of first-degree relatives of probands with negative gene testing were given an ICC diagnosis following clinical screening.

Conclusions

 This short study demonstrates the unique potential the SADS BioBank has to offer in terms of identifying those most at risk and optimising prevention strategies for relatives, thus highlighting the role for such a resource in terms of preventative screening in the future.

Pathogenic Variant (ACMG Class IV & V) Variant of Uncertain Significance(ACMG Class III) No Gene Variant Identified Number Detected (n = 24) 4 6 14 1st Degree Relatives Screened (n = 86) 17 20 49 2nd Degree Relatives Screened (n = 46) 4 23 19 Genotype Detected (n = 4) 3 1 0 Phenotype Detected (n = 10) 1 5 4 Breakdown of clinical and genetic results of family screening by ACMG class.

Abstract Figure.
P962Circumferential pulmonary vein ablation in combination with a linear lesion at the left atrial roof for catheter ablation of persistent atrial fibrillation (8.5-year follow-up)
Authors: Kettering C
Published: June 2020

Background

Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Circumferential pulmonary vein ablation is still the standard approach in these patients. However, the results are not very favourable and more complex ablation strategies are the subject of current controversy. Therefore, we have evaluated the effect of an additional linear lesion at the roof of the left atrium on the long-term outcome.

Methods

A total of 220 patients (114 men, 106 women; mean age 69 years (SD ± 14 years)) with symptomatic persistent atrial fibrillation underwent a circumferential pulmonary vein ablation procedure in combination with an additional linear lesion at the roof of the left atrium (group A). After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, 6, 12, 24, 36, 48, 60, 72, 84, 96 and 102 months after the ablation procedure. The long-term follow-up data was compared to 220 patients who underwent circumferential pulmonary vein ablation without an additional linear lesion at the roof of the left atrium (group B).

Results

The ablation procedure could be performed as planned in all patients. Fifty-one out of 220 patients (23.2 %) in group A and 53 out of 220 patients (24.1 %) in group B experienced an arrhythmia recurrence within the first 3 months after ablation requiring an electrical cardioversion. At 102-month follow-up, analysis of a 168-hour ECG recording revealed no evidence for an arrhythmia recurrence in 125/220 patients (56.8 %) in group A and in 103/220 patients (46.8 %) in group B. In 66/220 patients (30.0 %) in group A and 59/220 patients (26.8 %) in group B, only short episodes of paroxysmal atrial fibrillation were documented. In 29 patients (13.2 %) in group A, a recurrence of persistent atrial fibrillation (> 48 hours) was revealed by the long-term recordings (group B: 58 patients (26.4 %)). The lower arrhythmia recurrence rate in group A was partially due to a lower incidence of atypical atrial flutter after catheter ablation. The rate of repeat ablation procedures was significantly lower in group A than in group B. There were no major complications.

Conclusions

Catheter ablation of persistent atrial fibrillation comprising a circumferential pulmonary vein ablation and an additional linear lesion at the roof of the left atrium provides more favourable results than circumferential pulmonary vein ablation alone. The effect is more pronounced during long-term than during short-term follow-up.
P95412 lead Holter monitoring in Brugada syndrome
Authors: Carvalho P , Gravinese C , Previti A , Varalda G P , Montagna L
Published: June 2020

Background

12 lead-Holter monitoring is commonly used for the assessment  of type 1 Brugada repolarization"s burden. However, data considering the prevalence and morphology of premature ventricular contractions (PVC) in these patients is lacking.

Purpose. We investigated the prevalence of PVCs in subjects with Brugada syndrome (BRs) phenotype during 24-hour 12 lead-Holter monitoring (12-L Holter), trying to identify their origin according to morphology. 

Methods. From January 2013 to September 2018, a total of 156 patients with type 1 BRs phenotype (spontaneous or drug induced) were screened for PVCs. In these patients we placed the right precordial leads at the second (V1-V2) and the forth (V3-V4) intercostal spaces. 

Results. 83 subjects (53%) displayed PVCs. Their mean age was 50 years (range 21-73) and 63 (76%) were male. 14 subjects (17%) had a spontaneous type 1 repolarization whereas 69 (83%) presented a drug induced type 1. One patient had implanted an ICD as secondary prevention after an aborted sudden cardiac death. The others were mostly asymptomatic as only five of them (6%) had history of suspected cardiac syncope. 17 subjects (20%) had performed an electrophysiological study, which resulted positive in 3 cases (4%). The population without PVCs had similar baseline characteristics.

In 59 (71%) patients PVCs were monomorphic, in the other 29% we analyzed the prevalent morphology.

PVCs were classified according to their morphology as follows

(i) left bundle branch block (LBBB)/inferior axis suggesting an origin from the right ventricular outflow tract (RVOT), that was shown in 40 (48%) subjects; (ii) right bundle branch block (RBBB)/left axis suggesting an origin close to the posterior fascicle of the left bundle branch in 36 (43%). The other 7 patients presented several morphologies.

According to their number during the 24-hour monitoring, PVCs were arbitrarily classified as follows: (i) 1-59,present in 62 patients (75%); (ii) 60-749, present in 16 patients (19%); (iii) 750-9000, present in 4 patients (5%); (iv) >9000, in only one patient (1%). 

Conclusions. In our population of subjects with BRs phenotype the prevalence of PCVs is similar to that of the general population. Their morphologies suggest an origin from the RVOT or close to the posterior fascicle of the left bundle branch.
P492Estimation of no-flow duration and survival in patients with an initial shockable rhythm after out-of-hospital cardiac arrest
Authors: Goto Y , Funada A , Maeda T , Okada F , Goto Y
Published: June 2020

Funding Acknowledgements

Japan Society for the Promotion of Science (KAKENHI Grant No. 18K09999)

Background

In patients with unwitnessed out-of-hospital cardiac arrest (OHCA), the actual no-flow duration (the time with no organ perfusion) is unclear. However, when these patients have a shockable rhythm as an initial recorded rhythm, the no-flow duration may be relatively short as compared with other initial rhythms, and some patients can obtain a good functional outcome after OHCA.

Purpose

The purpose of the present study was to estimate the no-flow duration and to determine the relationship between no-flow duration and neurologically intact survival in patients with an initial shockable rhythm after OHCA.

Methods

We reviewed 82,464 patients with OHCA (aged ≥18 years, non-traumatic, witnessed, and without any bystander interventions) who were included in the All-Japan Utstein-style registry from 2013 to 2017. The study end point was 1-month neurologically intact survival (Cerebral Performance Category scale 1 or 2). No-flow duration was defined as the time from emergency call to emergency medical services (EMS) arrival at the patient site.

Results

The rate of 1-month neurologically intact survival in the patients with an initial shockable rhythm (n = 10,384, 12.6% of overall patients) was 16.5% (1718/10,384). No-flow duration was significantly and inversely associated with 1-month neurologically intact survival (adjusted odds ratios for 1-minute increments: 0.85, 95% confidence interval: 0.84–0.86). The proportion of patients with a shockable rhythm to the overall patients (y, %) had a high correlational relationship with no-flow duration (x, min), depicted by y = 21.0 - 0.95 × x, R² = 0.935. In this analytical model, the number of patients with shockable rhythm reached null at 22 minutes of no-flow duration. The no-flow durations, beyond which the chance for initial shockable rhythm diminished to <10%, <5%, and <1%, were 12, 13, and 17 minutes, respectively. The rate of neurologically intact survival in the patients with shockable rhythm (y, %) and no-flow duration (x, min) were also found to have a strong correlation, depicted by y = 0.16 × x² - 5.12 × x + 45.0, R² = 0.907. The no-flow durations, beyond which the chance for 1-month neurologically intact survival diminished to <10%, <5%, and <1%, were 10, 11, and 15 minutes, respectively.

Conclusions

In OHCA patients without any bystander interventions before EMS personnel arrival, when a shockable rhythm is recorded by EMS personnel as an initial rhythm, the no-flow duration after cardiac arrest is highly likely to be <17 minutes regardless of the layperson witness status. The limitation of no-flow duration to obtain a 1-month neurologically intact survival after OHCA may be 15 minutes when the patients have an initial shockable rhythm.
75Safety and efficacy of rivaroxaban in combination with anti-arrhythmic drugs in patients with non-permanent atrial fibrillation
Authors: Chiou W R , Chuang J Y , Huang C C , Lin P L , Lee Y H
Published: June 2020

Background

Rivaroxaban is useful for stroke prevention in atrial fibrillation (AF) patients. Most patients with non-permanent AF also treated with anti-arrhythmic drugs (AADs) to prevent the recurrence of arrhythmia. But there are limited data regarding drug-drug interactions between rivaroxaban and AADs despite its high clinical relevance.

Purpose

To compare the bleeding risks and ischemic events between the use of rivaroxaban alone and the concomitant use of AADs.

Methods

This is a multicenter retrospective study, which identified patients with a diagnosis of non-permanent AF who received rivaroxaban more than 1 month between December 1, 2011 and November 30, 2016. The study divided patients into 4 groups : rivaroxaban alone, combined with amiodarone, dronedarone and propafenone. We compared the clinical events and cumulative incidences to compare the endpoints including efficacy endpoint (new ischemic stroke, intracranial hemorrhage, or new

embolism), safety endpoints (Hb fall more than 2g/dL or transfusion more than 2U PRBC, critical site bleeding, or fatal bleeding.) and major adverse cardiovascular events (MACE), including cardiovascular death, myocardial infarction, new ischemic stroke, new embolism, or intracranial hemorrhage.

Results

Of 1777 enrolled patients, the rivaroxaban alone was 1205 cases, 177 in amiodarone group, 231 in dronedarone group and 164 in propafenone group. There was no statistically significant difference on efficacy endpoints, safety endpoints and MACE between the 4 groups. The average dosage of rivaroxaban was insignificantly the lowest in the group combined with dronedarone (12.3mg, p = 0.146). The rate of new embolism (0%, p = 0.029), recurrent heart failure admission rate (3.9%, p < 0.001), and all-cause mortality (3.0%, p = 0.013) in dronedarone group showed a significant lower occurrence rate. The occurrence rate of new ischemic stroke (0.9%, p = 0.549), new hemorrhagic stroke (0.4%, p = 0.546), efficacy endpoints (1.7%, p = 0.369) and MACE (3.9%, p = 0.72) in dronedarone droup were the lowest but insignificant. The cumulative incidences of efficacy endpoints, safety endpoints and MACE during follow-up period were also similar in these four groups.(Picture 1)

Conclusions

In patients with non-permanent atrial fibrillation, this real-world study showed that there were no significant differences between using rivaroxaban alone or concomitant with an AAD (dronedarone/amiodarone/propafenone) on events such as new ischemic stroke, intracranial hemorrhage, GI bleeding and MACEs. The happening of new embolism was lower especially in the group combined with dronedarone. The safety and efficacy between rivaroxaban alone and combined with rhythm control using AADs proved to be the same.  Relative low dose rivaroxaban combined with dronedarone did not increase the bleeding risk, and may decrease the probability of thromboembolism.

Abstract Figure. Picture 1
P1055Reduction of radiation exposure using an optimized fluoroscopy protocol in cryoballoon ablation does not compromise clinical outcome
Authors: Holl M J M , Bhagwandien R E , Firouzi M , De Ruiter W A , Szili-Torok T , Yap S C
Published: June 2020

Background/Introduction

Pulmonary vein isolation (PVI) using cryoballoon (CB) ablation is associated with an increased radiation exposure compared to radiofrequency ablation. Previous studies showed that radiation exposure in CB PVI can be reduced by optimizing the fluoroscopy protocol without comprising acute efficacy and safety.

Purpose

We evaluated the mid-term outcome of an optimized fluoroscopy protocol in patients undergoing CB PVI.

Methods

The study population comprised 90 consecutive patients who underwent second generation CB-based PVI. The first 46 patients underwent CB PVI with conventional fluoroscopy settings (Group A). In the following 44 patients (Group B) an optimized fluoroscopy protocol was applied consisting of 1) using fluoroscopy instead of filming for determining the pulmonary vein occlusion grade; and 2) optimal collimation of the area of interest. Primary endpoints were the total dose area product (DAP), fluoroscopy time and freedom from documented recurrence of atrial fibrillation (AF) after a single procedure.

Results

Group B had a lower median DAP (1393 cGycm2 vs. 3232 cGycm2, P < 0.001) and median fluoroscopy time (20 min vs. 24 min, P < 0.001) as compared to group A. The 1-year freedom from documented recurrence of AF after a single procedure was similar among groups (74% in Group A vs. 77% in Group B, P = 0.71). There were no significant differences between both groups for the secondary endpoints, including procedure duration, proportion of patients with complete electrical isolation, and complications.

Conclusion

Using an optimized fluoroscopy protocol in CB PVI radiation exposure could be reduced with a similar 1-year clinical outcome.
304Cryoablation versus Radiofrequency Ablation of the Atrioventricular Node in Patients with His-bundle Pacing
Authors: Zweerink A , Bakelants E , Stettler C , Burri H
Published: June 2020

Background

Atrioventricular node (AVN) ablation in the setting of His bundle pacing (HBP) may be challenging due to risk of compromising the function of the His lead. Cryoablation (CRYO) may offer theoretical advantages over conventional radiofrequency ablation (RFA), due to absence of shunting of current to the His lead, more discrete lesions, and potential reversibility in case of transient elevation of capture thresholds. However, CRYO has never been tested for AVN ablation in this setting.

Purpose

To compare procedural characteristics and outcome of CRYO compared to RFA for AVN ablation in patients with HBP.

Methods

Thirty-five patients (age 76 ± 8 yrs, 23% male) with HBP underwent AVN ablation for an "ablate and pace" indication. CRYO was performed in the first 22 pts and RFA in the following 13 pts. Procedure and fluoroscopy times, change in His threshold and success rates were compared between groups.

Results

The acute procedural success rate was 100% for both strategies without any major complications. There were no significant differences in procedure characteristics and outcome between CRYO and RFA, except for significantly shorter application times with RFA and a trend to more frequent reconduction and requirement for a redo procedure with CRYO (see table). All recurrences occurred within one month after ablation.

Conclusion

CRYO does not seem to offer any advantage over RFA for AVN ablation in patients with HBP, and does not avoid rise of His capture thresholds. Moreover, the recurrence rate may be higher with CRYO leading to more redo procedures.

Table Parameter CRYO (22 pts) RFA (13 pts) P-value Total procedure time (min) 50 [38 - 63] 40 [33 - 53] 0.257 Fluoroscopy time (min) 5.0 [2.2 - 5.4] 3.5 [1.9 - 9.0] 0.578 Expo Rx (mcGy.cm2) 237 [110 - 525] 139 [65 - 721] 0.468 Number of applications (n) 6 [3 - 11] 4 [1 - 15] 0.371 Total application time (min) 17 [9 - 29] 3 [1 - 9] 0.001 His threshold pre-ablation (V) 1.63 [0.75 - 3.44] 0.75 [0.53 - 1.63] 0.180 His threshold post-ablation (V) 1.88 [0.75 - 3.81]* 1.25 [0.63 - 3.50] 0.389 His threshold change (V) 0.00 [0.00 - 0.31]* 0.00 [0.00 - 0.75] 0.933 His threshold rise ≥1 volt (n) 4 (18%)* 3 (23%) 0.726 Acute procedural success (n) 22 (100%) 13 (100%) 1.000 AV reconduction during follow-up (n) 5 (23%) 1 (8%) 0.254 AV reconduction needing redo procedure (n) 3 (14%) 0 0.146 Interquartile range is shown in square brackets. *one loss of capture.
P991Pattern of rapid activity is preserved in persistent AF in selected locations after pulmonary vein isolation
Authors: Nagy S , Kasi P , Afonso V , Mann I , Kim S , Linton N , Lefroy D , Whinnett Z , Ng F S , Koa-Wing M , Kanagaratnam P , Peters N S , Qureshi N A , Lim P B
Published: June 2020

Funding Acknowledgements

Our research group receives an educational grant from Abbott Inc.

Introduction. There is evidence to suggest that structural remodelling in psAF potentially gives rise to areas of rapid cycle length activity that may act as driving mechanisms. We describe a new method to compare rapid activity (RA) in psAF prior to and after pulmonary vein isolation, in extended AF segments (EAFS). We focus on patterns of RA, based on the hypothesis that AF drivers are transient but recur in the same locations. 

Methods. Five patients (61 ± 8 years of age, 3 male) for catheter ablation of psAF were included. 3D maps were collected with a double spiral 20 pole catheter. In stable locations, pre and post PVI, 37s EAFS were recorded using 8s segments, automatically every 1s, creating a 7s overlap between segments. Dominant cycle length (DCL) was determined for every 8s segment by a fully automated algorithm. RA was defined as the rapidest 20th percentile for each patient. RA episodes consisted of continuous segments with rapid DCL (black lines in Fig 1) and terminated with a non-rapid segment (red lines on Fig 1). Episodes were truncated where overlap occurred (Box 1 and Box 2 in Fig 1). The pattern of RA was assessed by the number, cumulative duration and mean duration of RA episodes within an EAFS pre and post PVI.

Results. Mean DCL of EAFS increased significantly in 4/5 patients after PVI, the number of EAFS with rapid activity showed a reduction in all patients.  The percentage of new sites with RA post PVI was 27%. The number of sites that retained RA post PVI was 14 ± 11.3 (58.3%; Table 1).  Of these, number and cumulative duration of RA did not change in 4/5 patients, and mean duration of RA remained stable in 5/5.

Conclusion. An automated DCL algorithm shows that, in most cases, global AFCL prolongs significantly with PVI overall, but selected foci retain RA and RA patterns. These may represent active drivers, as their activity appears to be independent of their surroundings.

Table 1 Patient ID Number of segments Mean AFCL ± SD of all segments Number of EAFS with rapid activity Pre-PVI Post-PVI P Pre-PVI Post-PVI New sites 1 145 135 ± 8.9 141 ± 9.8 <0.001 94 62 15 2 121 154 ± 12.9 162 ± 15.0 <0.001 94 72 11 3 172 148 ± 13.7 160 ± 16.6 <0.001 108 82 25 4 301 172 ± 22.9 174 ± 21.5 0.418 198 189 58 5 200 177 ± 9.9 215 ± 18.1 <0.001 87 43 14 Pre and Post PVI cycle length and EAFS with rapid activity. (AFCL: AF cycle length; EAFS: Extended AF segments; PVI: Pulmonary vein isolation)

Abstract Figure.
P938Regulation of the delayed rectifier potassium current during the adrenergic adaptation of cardiomyocytes
Authors: Kiss D , Hezso T , Kurtan B , Veress R , Baranyai D , Kovacs Z S , Dienes C S , Szentandrassy N , Banyasz T , Magyar J , Nanasi P P , Horvath B
Published: June 2020

Funding Acknowledgements

Supported by the ÚNKP-19-3 New National Excellence program of the Ministry for Innovation and Technology

Introduction and aims

Adaptation of the human heart to physical activity is a complex mechanism that includes the change of heart rate, morphology of the action potential (AP) among others. Stimulation of β-adrenergic receptors (β-AR) causes the shortening of the AP duration of ventricular cardiomyocytes. This is caused by the regulation of the potassium currents by the β-adrenergic signaling pathway.

Our aim was to investigate the role of protein kinase A (PKA) and calcium/calmodulin-dependent protein kinase II (CaMKII) in the regulation of the slow component (IKs) of the delayed rectifier potassium current under β-AR activation.

Methods

Our experiments were performed on isolated canine cardiomyocytes from the left ventricle. The IKs current profile was determined under a ventricular AP. We used "AP voltage clamp" conditions in six experimental groups:

Control (CTRL),

β-AR stimulation with isoproterenol (ISO),

CaMKII inhibition with KN-93 (KN-93),

PKA inhibition with H-89 (H-89)

β-AR stimulation with inhibited CaMKII (KN-93 + ISO),

β-AR stimulation with inhibited PKA (H-89 + ISO).

β-AR stimulation with inhibited CaMKII and PKA (KN-93 + H-89 + ISO)

Results

The highest current density of IKs was approximately 6 times higher and the charge delivered by IKs was about 8 times larger in the ISO group than in CTRL or KN-93 conditions. In the KN-93 + ISO group, IKs amplitude was about 60% smaller and delivered about half the total charge compared to the ISO group. In the H‑89 + ISO group, IKs was about 30% smaller and delivered 40% less total charge than in the ISO group. In the KN-93 + H-89 + ISO group the IKs did not changed sicnificantly.

Conclusion

Based on our results, CaMKII plays an important role in regulating IKs by β-AR stimulation.
P1466Leadless pacemaker mid and long term follow-up in a single center-study
Authors: Martinez Sande J L , Garcia-Seara J , Gonzalez-Melchor L , Cacho-Antonio C E , Fernandez-Lopez X A , Rodriguez-Manero M , Abou-Jokh C , Lopez-Canoa J N , Gonzalez-Juanatey J R
Published: June 2020

Introduction and objectives

Initial results of Leadless pacemakers (LPM) has been promising in worldwide, nevertheless there are still no long term experience published, so the objective of our study was to evaluate electrical parameters at mid  and long term follow-up, describing as well total complications and mortality in a single center-study.

Methods

 

This was a prospective, observational clinical trial that included 183 consecutive patients, with an indication for a single-chamber pacemaker implantation.

Results

 

All successful implantation included a total of 183 patients with a mean age of 79,2 ±6,6 years (range 54-93y/o); 111 (60,6%) were men and more frequent rhythm was permanent atrial fibrillation (160), including those in which a node ablation was performed in the same procedure (22). Clinical and echocardiographyc characteristics are described in table 1.Mean follow-up was of 26 ±10 months including: 64 patient at 24 months, 46 at 36 months and 7 patients at 48 months. Electrical parameters are represented in figure 1, which were stable and flawless at long term follow-up.  Total complications were 3,3%, with only 2 patient requiring surgery for resolution (1,7%), and all were acute during LPM implantation. A total of 17 patients (9,3%) died with no relation to pacemaker. 

Conclusions

In our experience, leadless pacemakers electrical performance continues stable, appropriate at long term follow-up, and no other complications developed.

Baseline Characteristics of Patients Age(years) 79.2 ± 6.6[54-93] Male gender, n (%) 118 (60.6%) Hypertension, n (%) 149 (81.7%) Diabetes mellitus, n (%) 64 (34.9%) COPD, n (%) 33(18.3%) Renal dysfunction, n (%) 30 (16.7%) Valvular disease, n (%) 74 (41.1%) Atrial Fibrillation, n (%) 161 (98.0%) LVEF(%) 60.0 ± 8 OAC, n (%) 123(67.2%) NOAC, n (%) 23 (10.0%)

Abstract Figure. Electrical performance
P541Cardiac resynchronization therapy: left or non-left bundle branch block? That is the question
Authors: Aguiar Ricardo I , Nunes-Ferreira A , Rigueira J , Rodrigues T , Cunha N , Antonio P S , Morais P , Pereira S C , Bernardes A , Santos I , Magalhaes A , Neves H , Pinto F J , De Sousa J , Marques P
Published: June 2020

Introduction

Cardiac resynchronization therapy (CRT) is associated with reduced mortality and improved quality of life in patients (pts) with low ejection fraction (EF) and conduction delays. Patients with left bundle branch block (LBBB) seem to be the ones who benefit the most from CRT and there is controversy about its efficacy in patients with non-LBBB.

Purpose

To compare the prognostic impact and the response rate to CRT in patients with LBBB and non-LBBB.

Methods

Prospective single-center study of patients who implanted CRT between 2015 and 2019. Clinical, electrocardiographic and echocardiographic evaluations were made before CRT implant and between 6-12 months post-implant. Patients with EF elevation ≥ 10% or left ventricle end-systolic volume (ESV) reduction ≥ 15% were classified as responders. Patients with EF elevation ≥ 20% or LV ESV reduction ≥ 30% were classified as super-responders. All the parameters were compared between patients with or without LBBB. Prognostic impact of resynchronization therapy was evaluated by comparing total mortality using the Cox regression and Kaplan-Meier methods.

Results

From 2015-2019, 566 CRTs were implanted (26.1% female, 72 ± 10.2 years old, follow-up duration 18.9 ± 15.8 months). From these patients, 59% had LBBB (69% males, mean age 71.6 ± 10.8 years, 34.5% ischemic, EF < 30% in 65.5%). The cardiovascular risk factors and comorbidities were similar in both populations (with and without LBBB), except for diabetes which was more frequent in non-LBBB patients (33% vs 50.6%, p = 0.007). Mean duration of QRS was similar between LBBB vs non-LBBB patients (163 ± 19ms vs 160 ± 22ms, p = NS) and baseline ejection fraction was also equivalent (29.8 ± 13.6% vs 27.9 ± 8.9%).

The prevalence of complications and surgical revisions were similar in both groups.

The response rate according to left ventricle remodelling criteria was higher in LBBB pts (65.9% vs 49.1%, p < 0.05), but the super-responders were similar in both groups (32.5% vs 26.4% p = NS).

The 4-year survival rate of patients with LBBB and non-LBBB was similar (86.5% vs 85.3%).

Conclusion

In our population the response rate to CRT was higher in LBBB pts. However, and despite the actual controversy about the efficacy of CRT in non-LBBB, the long-term mortality was similar in patients with or without LBBB.

Abstract Figure. lon-term survival
P1149Subcutaneous implantable cardioverter-defibrillator when Transvenous ICD is not a viable option
Authors: Russo V , Molini S , De Bonis S , Ziacchi M , Ricciardi G , Migliore F , Viani S , Lavalle C , Pangallo A , La Greca C , Brambilla R , Tordini A , Ospizio R , Lovecchio M , Rago A
Published: June 2020

Funding Acknowledgements

NO FUNDING

OnBehalf

RHYTHM DETECT Registry

Background

The class of recommendation for S-ICD implantation in patients who have inadequate vascular access is I according to AHA-ACC-HRS Guidelines and IIb according to ESC Guidelines. Data are lacking about the use of S-ICD for patients in which a transvenous ICD is not a viable option because of the inability to deploy a transvenous lead.

Purpose

To describe current practice and to measure outcomes associated with S-ICD use in patients in which a transvenous ICD is not a viable option.

Methods

942 consecutive patients underwent S-ICD implantation at 22 Italian centers from 2014 to 2019. We identified 101 (11%) patients who received S-ICD because of the reported impossibility of deploying a transvenous lead.

Results

21 patients presented with inadequate vascular access but no previous device in place. One patient had a mechanical prosthesis in tricuspid position. The remaining 79 patients received the S-ICD after removal of a prior system implanted, and venous occlusion was diagnosed after lead extraction, or partially or completely failed lead removal. In 24 of these patients a functional transvenous pacing system was left in place for persisting pacing needs. Patients were 60 ± 15 years old, 85% were male, 77% had ischemic or non-ischemic dilated cardiomyopathy, ejection fraction was 36 ± 13%. At implantation, acute conversion test was performed in 64 patients and shock energy of ≤65J was successful in 62 (96.9%) patients. During a median follow-up of 18 months, 6 patients died for non-device related reasons and 1 patient underwent heart transplantation. One patient underwent device replacement for battery depletion and one patient underwent leadless pacemaker implantation. Minor complications (hematomas not requiring system revision) were reported in 2 patients. Appropriate therapies were delivered in 4 patients and 8 patients experienced inappropriate therapies (in 3 patients due to double counting during pacing); all resolved with device reprogramming. Conclusions: In current clinical practice, a minority of S-ICD patients receive the device because of inadequate vascular access. The profile of these patients is similar to that of the typical ICD population in the context of primary sudden death prevention, but many of them present with pacing indications. Acute and mid-term efficacy of S-ICD seemed high. Few complications occurred during follow-up. Particular attention must be paid to device programming for those patients with concomitant pacing systems, in order to prevent inappropriate therapies.
852Lead abandonment and subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation in a cohort of patients with ICD lead malfunction
Authors: Russo V , Viani S , Migliore F , Tola G , Bisignani G , Biffi M , Dello Russo A , Sartori P , Rordorf R , Ottaviano L , Perego G B , Papa A , Segreti L , Lovecchio M , Bongiorni M G
Published: June 2020

Funding Acknowledgements

NO FUNDING

OnBehalf

Rhythm Detect Registry

Background

Currently, when an implantable-cardioverter defibrillator (ICD) lead becomes nonfunctional, a class IIa recommendation exists for either lead abandonment or for removal. The benefits of removal include creation of an access for insertion of a new lead.  However, the subcutaneous ICD (S-ICD) does not require the insertion of any leads into the cardiovascular system, and may represent an additional option for patients not requiring pacing.

Purpose

 To report outcomes associated with a strategy of lead abandonment and S-ICD implantation in the setting of lead malfunction.

Methods

We analyzed all consecutive patients who underwent S-ICD implantation after abandonment of malfunctioning leads and we compared outcomes with those of patients who underwent transvenous extraction and subsequent reimplantation of a single-chamber transvenous ICD (T- ICD).

Results

43 patients were implanted with an S-ICD after abandonment of malfunctioning leads, while in 62 patients extraction and subsequent reimplantation of a T-ICD. The two groups were comparable (Age 55 ± 16 vs. 54 ± 33years, BMI 26 ± 3 vs. 24 ± 4kg/m2, LVEF 43 ± 15 vs. 48 ± 8%). S-ICD defibrillation test success rate at implantation was 96% at 65J. In the extraction group, no major complications were reported during extraction, while the procedure failed and an S-ICD was implanted in 4 patients. During a median follow-up of 21 months, the rate of major complications was not higher in the S-ICD group than in the T-ICD group (HR 1.07; 95%CI 0.29–3.94; P = 0 .912; Figure), as well as the rate of minor complications (HR 2.13; 95%CI 0.49–9.24; P = 0 .238).

Conclusions

 In case of ICD lead malfunction, extraction prevents potential long-term risks of abandoned leads, e.g. increased complications for a possible future mandatory extraction indication such as infection, and allows magnetic resonance imaging. Nonetheless in this series, the strategy of lead abandonment and S-ICD implantation appeared to be feasible and safe with no significant increase in adverse outcomes for patients not requiring pacing and may represent an option in selected clinical settings (very high risk or failed extractions, older patients, etc.). Longer follow-up studies are needed to fully understand the potential risks of lead abandonment.

Abstract Figure
P1168Redefining first degree AV block: constant fusion pacing CRT is easier in longer PR interval patients
Authors: Vacarescu C , Luca C T , Petrescu L , Mornos C , Goanta E V , Crisan S , Lazar M A , Cozlac R A , Cozma D
Published: June 2020

Background

LV only pacing is non-inferior to BiV pacing, and recent publications showed that DDD CRT without RV lead is safe in patients with normal atrioventricular (AV) conduction, although there are no device algorithms available for fusion pacing and PR interval variability is understudied in this population. Purpose: To analyse AV behaviour in pts with DDD CRT and the impact to effective fusion maintenance.

Methods

Consecutive pts with right atrium/left ventricle (RA/LV) DDD CRT pacing system were included. Prospective data were collected at every 6 months follow-up visits: device interrogation, exercise test (ET), echocardiography. CRT assessment during ET analysed loss of LV capture with special focus on maintaining constant fusion pacing during exercise. We defined 2 groups of pts: longer PR interval pts (200-250 ms) and normal PR interval pts (˂200 ms). In case of LV loss of capture or unsatisfactory LV fusion pacing, device reprogramming was performed individualised for each patient and BB/ivabradine dose titration was done to achieve stability of PR spontaneous interval. Patients were rescheduled in no later one month to be reassessed by ET.

Results

55 pts (29 male) aged 62 ± 11 y.o. were included, 36 pts with normal PR and 19 pts with longer PR. During follow-up (45 ± 19 months), a total of 235 ETs were performed with mean exercise load 118 ± 35 watts. In the normal PR group 14 pts (39%) had inadequate pacing or loss of LV capture during ET due to physiological shortening of PR interval vs. 4 pts (21%) in the long PR group. Loss of LV capture by exceeding maximum tracking rate (MTR) was noted in 6 pts (17%) with normal PR vs. 2 pts (11%) with longer PR. Post ET device optimisation included:  reprogramming rate adaptive AV interval (23 ± 8 ms decrease in normal PR pts vs. 12 ± 7 ms in longer PR pts, p < 0.0001) and individualised programming of MTR. BB/ivabradine optimisation was performed in 32% of pts with normal PR vs. 13% of pts with longer PR.

Conclusions

A lower rate of optimisations after exercise test was needed in pts with a slightly longer AV conduction to achieve stability of fusion pacing DDD CRT without device algorithms. Larger studies are needed to assess AV conduction variability and the benefits of fusion pacing CRT in pts with longer PR interval.

Abstract Figure.
P1125 Safety and efficacy of ventricular tachycardia ablation during sinus rhythm in patients with structural heart disease
Authors: Fernandez-Armenta Pastor J , Silva E , Soto-Iglesias D , Penela D , Acosta J , Jauregui B , Bisbal F , Linhart M , Fernandez M , Borras R , Villuendas R , Cano L , Berruezo A
Published: June 2020

Funding Acknowledgements

Project “PI-0057-2017”, funded by Junta de Andalucía and co-funded by European Union (ERDF/ESF, “Invesing in your future”)

Background

The best strategy for scar related ventricular tachycardia (VT) ablation is not yet established. Recently, the use of ventricular assist devices is being proposed to allow ablation during unstable VT. 

Purpose

Analyze the results of a multicenter registry of substrate-guided VT ablation performed primarily during stable rhythm.

Methods 

This prospective multicenter registry included 433 VT ablation procedures performed in 372 consecutive patients with structural heart disease undergoing VT ablation. Substrate ablation (scar dechanneling technique) during sinus rhythm without initial VT induction was the standard protocol. Any episode of sustained VT or appropriate ICD therapy was considered VT recurrence. 

Results 

Myocardial infarction was the arrhythmogenic substrate in 64% of patients. 90.5% of patients were male, mean age 64 ± 13 years. Mean LVEF was 38 ± 13%.No ventricular assist device was used in any case. After substrate ablation no VT was inducible in 69% of cases. End-procedure non-inducibility was achieved in 73.1% of cases. Complication rate was 6.7 %. 30-days mortality was 1.9% (7 patients), including one procedure related death. At one year after first procedure 17 patients died (4.5%). Age, chronic obstructive pulmonary disease and renal failure were independent predictors of mortality. One-year freedom from VT recurrence was 84%. 

Conclusion

Substrate-guided VT ablation during stable rhythm as main approach for scar-related VT treatment is associated to low complication and recurrence rates in this prospective multicenter study.
64effects of long-term exercise training and detraining on endothelial function and arterial stiffness in patients with atrial fibrillation: a randomized controlled trial with 1-year follow-up
Authors: Kim S , Han D , Jeong I , Lee H , Koh Y , Lee S
Published: June 2020

Introduction

Exercise training (ET) improves endothelial function and arterial stiffness in patients with cardiovascular disease. However, whether ET improves endothelial function and arterial stiffness in patients with atrial fibrillation (AF) is unclear. If it does, for how long the effects are sustained remains to be determined.

Methods

In a prospective study, 58 patients with AF (age, 62 ± 7 years) were randomized into an ET group for 12 months (CT, n = 13), a group with 6-month detraining after a 6-month ET (DT, n = 15), and a medical treatment only group (MT, n = 30). For ET, cycling on a bicycle ergometer was performed in the DT and CT groups 3 times a week for 6 and 12 months, respectively. Each session started with a 10-minute warmup at 60% to 70% of the maximal heart rate (HRpeak), followed by four 4-minute intervals at 80% to 90% of the HRpeak, with 3 minutes of active recovery at 60% to 70% of the HRpeak between intervals, ending with a 5-minute cooldown period. Peak exercise oxygen consumption (Vo2), intimal-medial thickness (IMT) of the carotid artery measured on high-resolution ultrasonography, and left ventricular function were measured at baseline, after 6 months of training, and after additional 6 months of continuous training or detraining follow-up assessments. In addition, plasma von Willebrand factor (vWF), endothelin-1, nitric oxide, tumour necrosis factor alpha, interleukin-1 beta, interleukin-6, and interleukin-10 levels were measured as indices of endothelial function.

Results

The 6-month ET increased peak Vo2 (CT: 29.0 ± 6.5 ml/[kg·min] and DT: 26.0 ± 8.2 ml/[kg·min] vs. MT: 23.0 ± 5.2 ml/[kg·min], p = 0.04) and decreased plasma vWF levels (CT: 103.7 ± 30.7 IU/dL and DT: 106.0 ± 31.2 IU/dL vs. MT: 145.0 ± 47.7 IU/dL, p = 0.01). Detraining significantly reduced the ET-induced increase in Vo2 and decreased the vWF to baseline level, although continuous ET maintained changes in Vo2 (CT: 28.1 ± 5.3 ml/[kg·min] and DT: 22.4 ± 6.6 ml/[kg·min] vs. MT: 21.5 ± 4.8 ml/[kg·min], p = 0.043) and in vWF (CT: 84.3 ± 39.1 IU/dL vs. DT: 122.2 ± 27.5 IU/dL and MT: 135.9 ± 50.4 IU/dL, p = 0.014). However, carotid arterial IMT, and resting left ventricular systolic and diastolic functions showed no significant changes, with no inter-group differences after 6 months of training and 6 months of continuous training or detraining.

Conclusions

The decreased vWF level suggested that ET can be a strong non-pharmacologic option to improve endothelial function in patients with AF. However, it can rapidly lose its effects after detraining. Therefore, physicians should encourage their patients to participate in a continuous exercise program to sustain its benefits in terms of improved exercise capacity and endothelial function in patients with AF.