bluuebunny/crossref_metadata_2025 huggingface dataset:
Is higher power shorter duration radiofrequency energy is better than lower power longer duration strategy in catheter ablation of atrial fibrillation A meta-analysis
Authors: Khanra D , Aggarwal P , Kumar H , Mishra V , Jain B , Reddy K.K
Published: November 2020

Background

An ideal strategy for radiofrequency ablation (RFA) of atrial fibrillation (AF) in the left atrium should be efficient enough to achieve transmural lesions in left atrium with no or minimal collateral tissue damage. Resistive heating of high power short duration (HPSD) RFA has been found to result in lesions larger in width but lesser in depth compared to lower power longer duration (LPLD) RFA in some experimental studies.

Purpose

This meta-analysis was performed to compare procedural, short-term and long-term outcomes of HPSD versus LPLD RFA of AF.

Methods

PubMed, Embase and Cochrane databases were systematically reviewed. Five observational studies meeting criteria were included in the meta-analysis. All the studies scored six or more points in the New-castle Ottawa scale. There were considerable variations in the ablation strategies across the studies. However, radiofrequency power more than 40W was considered as high power. Hypergeometric model with exact likelihood function was utilized for statistical analysis.

Results

Baseline parameters and ablation details have been depicted in Table 1. 740 patients with HPSD and 287 patients with LPLD ablation strategies, were followed up from 6 to 30 months. Total procedural time (P value <0.0001) and ablation time (P value <0.0001) were significantly lower in the HPSD group than LPLD group. However, the fluoroscopy time was similar (P value = 0.09) in both the groups (Table 2). There were no occurrences of atrio-esophageal fistula or pulmonary venous stenosis in any of the studies. Cardiac tamponade (P value = 0.56), stroke (P value = 0.70) and AF recurrences (P value = 0.81), were similar in both groups (Table 2).

Conclusion

Newer HPSD and conventional LPLD RFA, both the strategies are very safe procedure for treatment of RFA with low to no procedural complications. AF recurrence rates were reasonably high irrespective of ablation strategies, however, no strategy scored statistically better over the other one. Large randomized multi-centric studies with long-term follow up are needed to test the theoretical advantage of HPSD ablation over the traditional ablation strategy of AF.

Funding Acknowledgement

Type of funding source: None
A machine-learning algorithm to predict atrial fibrillation recurrence after a pulmonary vein isolation procedure
Authors: Nascimento Matos D , Ferreira A.M , Sousa A , Rodrigues G , Carmo J , Freitas P , Guerreiro S , Abecasis J , Costa F , Carmo P , Saraiva C , Cavaco D , Morgado F , Mendes M , Adragao P
Published: November 2020

Background

Contemporary risk models to predict the recurrence of atrial fibrillation (AF) after pulmonary vein isolation have limited predictive ability. Models with high specificity seem particularly suited for the setting of AF ablation, where they could be used as gatekeepers to withhold intervention in patients with low likelihood of success. Machine learning (ML) has the potential to identify complex nonlinear patterns within datasets, improving the predictive power of models. This study sought to determine whether ML can be used to better identify patients who will relapse within one year of an AF ablation procedure.

Methods

We assessed 484 patients (294 men, mean age 61±12 years, 76% with paroxysmal AF) who underwent radiofrequency pulmonary vein isolation (PVI) for symptomatic drug-refractory AF. Using this dataset, a machine-learning model based on Support Vector Machines (SVM) was developed to predict AF recurrence within one year of the procedure. The following variables were used to feed the model: type of AF (paroxysmal vs. non-paroxysmal), previous ablation procedure, left atrium (LA) volume, and epicardial fat volume (both derived from pre-ablation cardiac CT). The algorithm was trained in a random sample of 70% of the study population (n=339) and tested in the remainder 30% (n=145).

Results

A total of 130 patients (27%) suffered AF recurrence within one year of the procedure. The ML model predicted AF recurrence with 75% accuracy (95% CI 67–82%), yielding a sensitivity and specificity of 25% (95% CI 13–41%) and 94% (95% CI 88–98%), respectively. The corresponding positive and negative predictive values were 62% (95% CI 39–81%) and 77% (95% CI 67–82%), respectively. The relative weight of the variables in the ML model was: epicardial fat 56%, type of AF 23%, previous ablation 14%, and LA volume 7%. A high-risk subgroup representing 10.8% of patients was identified with the ML algorithm. In this subgroup, one-year recurrence was 62%, representing 24% of the total number of recurrences.

Conclusion

A machine-learning model showed high specificity in the identification of patients who relapse during the first year after AF ablation. In the future, these tools may be useful to improve patient selection.

Funding Acknowledgement

Type of funding source: None
Catheter ablation in atrial fibrillation: comorbidities and mortality from high-volume centers
Authors: Sousa J , Carmo J , Matos D , Rodrigues G , Ferreira A , Alencar J , Klemtz F , Durazzo A , Carvalho S , Costa F.M , Carmo P , Parreira L , Morgado F , Cavaco D , Adragao P
Published: November 2020

Background

Catheter ablation (CA), has gained wider acceptance as an attractive option for treating symptomatic AF. Although traditionally seen as a safe procedure, there is limited and conflicting data on procedure-related early morbimortality, with new evidence suggesting early mortality may be as high as 0.5%-1%.

Purpose

We aimed to assess the rates of early and late morbimortality of post-atrial fibrillation (AF) ablation in high-volume centers.

Methods

Prospective registry of 2 high-volume ablation centers, comprising 3722 consecutive patients (mean age 61.1±11.2, 66.4% male, n=2471), who underwent AF ablation from 2005 to 2019. Early mortality was defined as death during initial admission or during the first 45 days after ablation. Median follow-up time was 5.4 years.

Results

Most patients were treated with radiofrequency (97%) while 3% were treated with cryoablation. Early mortality was 0.08% (n=3), with a median time from ablation to death of 22 days. Cumulative mortality at 3, 6 and 12 months was 0.08%, 0.16% and 0.19%, respectively. At 3 and 5 years, mortality remained low at 0.48% and 0.73%, respectively. Early mortality was higher among patients who had suffered procedural complications (fistula and stroke, p<0.001). Among the latter, pericardial effusion and tamponade were the most frequently found (0.6%, n=24), only 1 of which required emergent surgical drainage and myocardial repair. Early ischemic stroke occurred in 2 patients (0.1%). Other less frequent complications were atrio-esophageal fistula (0.1%, n=2), phrenic nerve palsy (0.1%, n=2), anoxic encephalopathy following cardiac arrest (0.03%, n=1) and pulmonary vein stenosis (0.03%, n=1).

Conclusion

Early mortality following ablation is very low (<0.1%), when performed by an experienced high-volume team. Severe complications are rare (<1%) and mostly amenable to treatment. Our findings reaffirm the overall safety of AF ablation.

AF catheter ablation morbimort

Funding Acknowledgement

Type of funding source: None
Pulmonary vein isolation procedure may be associated with intracranial artery microembolism and increased risk of acute neurological incidents
Authors: Lasek-Bal A , Puz P , Wieczorek J , Nowak S , Wnuk-Wojnar A.M , Warsz-Wianecka A , Mizia-Stec K
Published: November 2020

Background

Atrial fibrillation ablation can be associated with the microembolism detected in intracranial arteries and risk of acute neurological incidents.

Purpose

The aims of this study were a quantitative and a qualitative evaluation of microembolic signals (MES) during pulmonary vein isolation (PVI) and establishing the potential significance of MES for damage of brain assessed in radiological investigation and neurological state of patients.

Methods

To the prospective project we qualified patients with atrial fibrillation undergoing percutaneous pulmonary vein isolation (radiofrequency ablation / balloon cryoablation) with ultrasound monitoring of microembolisms in right middle cerebral artery. Baseline and up to 12 months post pulmonary vein isolation the neurological examination and brain MRI were performed in all participants.

Results

The study enrolled 80 patients at a mean age of 58 years. Microembolisms during the monitoring of the flow in the right middle cerebral artery were recorded in 61 (76.3%) patients in the amount of 51–489 (mean 239). Most often the microembolic signals were registered during the trans-septal puncture and the stage of ablation. In 89%, microembolisms were gaseous. Mean score on Fazekas scale for the whole group before ablation: 0.87±0.7 (0–3, med. 1); after: 0.93±0.71. In 3 (4.3%) patients the lesions worsened during the follow-up period. None of the patients revealed a cardiovascular event during the follow-up period and no changes were observed in the neurological status.

Conclusions

The majority of cerebral microembolism generated during PVI are gaseous in nature. The cerebral microembolism associated with PVI probably result from the technical aspects of the procedure and do not cause neither the permanent brain damage in the radiological investigation nor neurological deficit.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Medical University of Silesia, Katowice, Poland - statutory work
Electrical posterior box isolation in persistent atrial fibrillation changed to paroxysmal atrial fibrillation: a multi-center, prospective, randomized study
Authors: Pak H.N , Park J.B , Yu H.T , Kim T.H , Uhm J.S , Joung B.Y , Lee M.H , Kim Y.H , Shim J.M
Published: November 2020

Background

Persistent atrial fibrillation (PeAF) can change to paroxysmal AF (PAF) after antiarrhythmic drug medication and cardioversion.

Purpose

We investigated whether electrical posterior box isolation (POBI) may improve rhythm outcome of catheter ablation in those patient group.

Methods

We prospectively randomized 114 patients with PeAF to PAF (male 75%, 59.8±9.9 years old) to circumferential pulmonary vein isolation (CPVI) alone group (n=57) and additional POBI group (n=57). The primary end-point was AF recurrence after a single procedure, and the secondary end-point was a recurrence pattern, cardioversion rate, and the response to antiarrhythmic drugs (AADs).

Results

After a mean follow-up of 22.5±9.4 months, the clinical recurrence rate did not significantly differ between the two groups (29.8% vs. 28.1%, p=0.836; log rank p=0.815) The recurrence rate for atrial tachycardias (17.6% vs. 43.8%, p=0.141) was higher in POBI group, but the cardioversion rates (13.5% vs. 8.5%, p=0.434) were not significantly different between two groups. At the final follow-up, sinus rhythm was maintained without antiarrhythmic drug in 52.6% in CPVI group and 59.7% of POBI group (p=0.452). No significant difference was found in the major complication rates between the two groups (5.3% vs. 1.8%, p=0.618), but the total ablation time was significantly longer in the POBI group (4397±842 sec vs. 5337±1517 sec, p<0.001).

Conclusion

In patients with persistent AF converted to paroxysmal AF by AAD, the addition of POBI to CPVI did not improve the rhythm outcome of catheter ablation nor influence overall safety.

Funding Acknowledgement

Type of funding source: None
The outcome of ablation for non-paroxysmal atrial fibrillation targeting spatiotemporal electrogram dispersion compared with ganglionated plexi ablation
Authors: Sakata K , Tanaka T , Yamashita S , Yamashiro K
Published: November 2020

Background

Although catheter ablation targeting ganglionated plexi (GP) playing an important role in formation of triggers and substrates of atrial fibrillation (AF) has been reported as one of the effective ablation strategies in non-paroxysmal AF (non-PAF) patients, its effectiveness varies among the study groups. More recently, ablation targeting spatiotemporal electrogram dispersion (STED) areas, assumed to contain AF drivers in forms of rotational activation is proposed. However, the optimal ablation strategy for non-PAF is still controversial since the exact mechanisms of non-PAF are not well understood.

Purpose

To investigate the effectiveness of GP ablation for autonomic modification and STED ablation for modulation of AF drivers.

Methods

Consecutive 149 non-PAF patients who underwent STED ablation in our center were enrolled. We detected STED areas within the whole left and right atrium during AF using PentaRay®, and ablated them. If AF was terminated during STED ablation, we finished the procedure without burning the remaining STED areas. If not, electrical cardioversion was applied. The outcome was compared with that in consecutive 156 non-PAF patients undergoing GP ablation previously in our center.

Results

(1) The clinical characteristics were comparable between two groups (see Table). (2) A Kaplan-Meier curve showed that there was no significant difference between the freedom rates from non-PAF/non-paroxysmal atrial tachycardia (non-PAT) after single procedure in STED group and GP group (Figure, left). (3) However, the freedom rates from non-PAT in STED group was significantly lower than that GP group (Figure, right).

Conclusions

The recurrence type of atrial arrhythmia after ablation was remarkably different between ablation of STED and GP. STED ablation might eliminate fibrillatory conduction and control AF driver in patients with non-PAF.

Freedom from atrial arrhythmia

Funding Acknowledgement

Type of funding source: None
Complete transmural epicardial ablation reduces organized areas in atrial fibrillation
Authors: Rogers A , Ravi N , Bhatia N.K , Shah R.L , Pong T , Tung J.S , Purewal S , Baykaner T , Rappel W.J , Brodt C.R , Wang P.J , Lee A , Narayan S.M
Published: November 2020

Background

The surgical maze is suggested to be effective in persistent atrial fibrillation (AF) by reducing the area for fibrillatory wavelets. However, the mechanism for recurrence and next treatment steps are unclear.

Purpose

We set out to evaluate the impact of complete transmural epicardial maze lesion sets on the extent atrial organization using novel analyses of wide-area recordings of AF.

Methods

19 patients (age 50.9±12.0, 78% male) underwent maze followed by endocardial mapping of AF with a 64-pole basket catheter. Block across roof, floor, and pulmonary vein lesions sets was assessed by high-density voltage mapping and organized zones of AF were assessed by panoramic recordings. Total organized area and mean area of the dominant site were evaluated using automated custom scripts.

Results

Patients had 3.2±0.9 organized regions in 1 minute of LA recordings. A 54 yo F showed residual conduction to the posterior wall from the roof (purple, Fig. 1A) and a figure-of-8 propagation pattern during AF (arrows, fig B) which terminated with localized ablation (yellow lesions, Fig. 1A, red X, Fig. 1B). Overall, patients with complete block on epicardial lesion set had smaller areas of organization (13.7±8% vs. 45.7±32% of mapped areas, p=0.029) vs. those with gaps. The average size of the dominant area was smaller with complete transmural lines than with gaps (5.7±3% vs. 15.9±10%, p=0.033) (Fig. 1C).

Conclusion

These results show that complete transmural lesion sets constrain the critical mass available for AF, with smaller resulting organized zones. Future studies that quantify how partitioning the atrial surface affects AF may help personalize lesion sets after maze.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): NIH NRSA F32 United States
Motivational Interviewing to Support Oral AntiCoagulation adherence in patients with non-valvular Atrial Fibrillation (MISOAC-AF): a randomised clinical trial
Authors: Tzikas A , Samaras A , Kartas A , Vasdeki D , Fotos G , Dividis G , Paschou E , Forozidou E , Tsoukra P , Kotsi E , Goulas I , Karvounis H , Giannakoulas G
Published: November 2020

Background

Oral anticoagulation (OAC) is paramount to effective thromboprophylaxis; yet adherence to OAC remains largely suboptimal in patients with atrial fibrillation (AF).

Purpose

We aimed to assess the impact of an educational, motivational intervention on the adherence to OAC in patients with non-valvular AF.

Methods

Hospitalised patients with non-valvular AF who received OAC were randomly assigned to usual medical care or a proactive intervention, comprising motivational interviewing and tailored counseling on medication adherence. The primary study outcome was adherence to OAC at 1-year, evaluated as Proportion of Days Covered (PDC) by OAC regimens and assessed through nationwide prescription registers. Secondary outcomes included the rate of persistence to OAC, gaps in treatment, proportion of VKA-takers with labile INR (defined as time to therapeutic range<70%) and clinical events.

Results

A total of 1009 patients were randomised, 500 in the intervention group and 509 in the control group. At 1-year follow-up, 77.2% (386/500) of patients in the intervention group had good adherence (PDC>80%), compared with 55% (280/509) in the control group (adjusted odds ratio 2.84, 95% confidence interval 2.14–3.75; p<0.001). Mean PDC±SD was 0.85±0.26 and 0.75±0.31, respectively (p<0.001). Patients that received the intervention were more likely to persist in their OAC therapy at 1 year, while usual medical care was associated with more major (≥3 months) treatment gaps [Figure]. Among 212 VKA-takers, patients in the intervention group were less likely to have labile INR compared with those in the control group [21/120 (17.1%) vs 34/92 (37.1%), OR 0.33 95% CI 1.15–0.72, p=0.005]. Clinical events over a median follow-up period of 2 years occurred at a numerically lower, yet non-significant, rate in the intervention group [Table].

Conclusions

In patients receiving OAC therapy for non-valvular AF, a motivational intervention significantly improved patterns of medication adherence, without significantly affecting clinical outcomes.

Primary and secondary outcomes

Funding Acknowledgement

Type of funding source: None
Vitamin K antagonists versus direct oral anticoagulants after cardiac surgery: a 31-country cohort study
Authors: Whitlock R , Belley-Cote E.P , Healey J , Devereaux P.J , Eikelboom J , Lamy A , Brady K , Marsella B , Tagarakis G.I , Paparella D , Reents W , Punjabi P , Connolly S
Published: November 2020

Background

About 10% of patients undergoing cardiac surgery have a history of atrial fibrillation (AF). Among these patients, uncertainty exists regarding the safest and most effective oral anticoagulant (OAC) during the postoperative period.

Purpose

To evaluate practice patterns regarding OAC early after cardiac surgery in patients with a preoperative history of AF and to compare the safety and effectiveness of direct oral anticoagulants (DOACs) versus vitamin K antagonists (VKAs).

Methods

We conducted a nested cohort study within the Left Atrial Appendage Occlusion Study (LAAOS) III (NCT01561651). LAAOS III included patients with AF undergoing cardiac surgery with a CHA2DS2-VASC ≥2. In this substudy, we examined patients without end-stage renal dysfunction (eGFR >30 mL/min/1.73m2) who were discharged on OAC. We evaluated bleeding and thromboembolism within 90 days postoperatively using logistic regression adjusting for CHA2DS2-VASC score.

Results

Recruitment started in 2012 and completed in 2018 in 113 centres in 31 countries. Of the 4811 patients enrolled in LAAOS III, 3725 (77%) were included in this substudy. Preoperatively, 58% of patients received OAC: 56% DOACs and 44% VKAs. At hospital discharge 23% received DOACs and 77% VKAs; 55% of patients on a DOAC at baseline were switched to a VKA while 5% of patients on a VKA were switched to a DOAC. Patients discharged on a DOAC were older, had a higher CHA2DS2-VASC, and were more likely to be male. Patients having undergone an isolated coronary bypass procedure were more likely prescribed DOACs than VKAs (41% vs 23%, p<0.001) whereas isolated non-mechanical valve patients were more likely to be prescribed VKAs (43% vs 28%, p<0.001). Switching from a DOAC to a VKA postoperatively occurred in 42% of patients In Australia/New Zealand, 49% in Europe, and 63% in North America. Major bleeding between 48 hours postoperatively and 30 days occurred in 1.5% in the DOAC group and 1.3% in the VKA group (aOR 1.14, 95% CI 0.60–2.15, p=0.69) while between 48 hours and 90 days, it occurred in 1.8% of patients in both groups (aOR 0.97, 95% CI, 0.54–1.17, p=0.91). Cardiac tamponade, the composite of stroke and systemic arterial embolism, and the composite of stroke, systemic arterial embolism and death did not differ significantly at 30 and 90 days between the DOAC and VKA groups.

Conclusions

VKAs was the dominant OAC used early after cardiac surgery, but postoperative OAC practices varied by region. After adjustment for CHA2DS2-VASC score, the early postoperative incidence of major bleeding and of the composite of stroke and systemic arterial embolism did not differ significantly when DOACs were compared with VKAs.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): CIHR, Heart and Stroke Foundation
Effectiveness and safety of non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients with antiphospholipid syndrome: a nationwide cohort study
Authors: Yang P.S , Shim M , Kang S.H , Kim S.H , Kim W.J , Moon J.Y , Sung J.H , Kim I.J , Lim S.W , Cha D.H , Lip G.Y.H , Joung B
Published: November 2020

Background and objectives

Non-vitamin K antagonist oral anticoagulants (NOACs) are an effective and safe alternative to warfarin in atrial fibrillation (AF) patients, but there is not enough evidence that NOACs can offer sufficient protection in AF patients concomitantly diagnosed with antiphospholipid syndrome (APS). Use of rivaroxaban has been associated with an increased risk of thrombotic events compared with warfarin in results of the TRAPS trial, but the TRAPS trial is not for AF patients and included only very high-risk APS patients with triple-positive for all 3 antiphospholipid antibodies. We sought to compare thromboembolic events, bleeding, and mortality between NOAC and warfarin in patients with both AF and APS.

Methods

From the Korean National Health Insurance Service (NHIS) database during the period from January 1, 2011 to December 31, 2016, we identified an warfarin-treated group of patients with AF and APS (n=1,237) who were compared with a 1:1 propensity-matched NOAC treated group (n=1,237).

Results

After a median follow-up period of 17 months, NOAC-treated patients had lower incidence rates for ischemic stroke (5.9 and 10.5 events per 100 person-years for the NOAC and warfarin groups), major bleeding (4.1 and 8.3 events per 100 person-years, respectively), and all-cause mortality (3.4 and 15.6 events per 100 person-years, respectively) compared with warfarin in patients with AF and APS. Compared with warfarin, NOAC significantly decreased the risk of ischemic stroke (hazard ratio [HR]: 0.60, 95% confidence interval [CI]: 0.47–0.77, p<0.001), major bleeding (HR: 0.54, 95% CI: 0.41–0.72, p<0.001) and all-cause mortality (HR: 0.32, 95% CI: 0.27–0.40, p<0.001) with considering competing risk of death.

Conclusions

Compared with warfarin, AF patients with APS on NOACs had lower ischemic stroke, major bleeding, and all-cause mortality. Our data suggest that AF patients with APS can be safely and effectively treated with NOACs.

Funding Acknowledgement

Type of funding source: None
Effect of continuous positive airway pressure therapy in patients with paroxysmal atrial fibrillation and obstructive sleep apnea: a randomized controlled trial
Authors: Traaen G.M , Aakeroy L , Hunt T.E , Overland B , Bendz C , Sande L.O , Aakhus S , Zare H , Fagerland M , Steinshamn S , Bredesen N , Anfinsen O.G , Akre H , Loennechen J.P , Gullestad L
Published: November 2020

Background

There is strong evidence for an association between atrial fibrillation (AF) and sleep apnea (SA).

Purpose

We aimed to examine the effect of treatment with continuous positive airway pressure (CPAP) on the burden of AF.

Methods

After a run-in period for CPAP-tolerance, we randomly assigned 108 eligible patients between 18–75 years, who had paroxysmal AF and moderate-to-severe obstructive SA (apnea-hypopnea index (AHI)≥15), to receive either CPAP treatment (n=54) plus usual care or usual care alone (n=54) for five months. An implanted loop recorder measured time in AF continuously. The primary endpoint was the difference in change of AF burden (% of time in AF) between CPAP treatment and usual care from baseline (one month prior to randomization) to the last three months of the intervention period. Secondary endpoints were changes in quality of life assessed by the Short Form-36 (SF-36), Epworth Sleepiness Scale (ESS), and the Functional Outcomes of Sleep Questionnaire (FOSQ).

Results

Mean (SD) age was 62.4 (7.7) years, BMI 29.4 (4.2) kg/m2, ESS 7.9 (3.2), and 76.1% were men. In the intervention group, the mean duration of adherence to CPAP therapy was 4.3 hours/night. During treatment mean AHI decreased from 27.6 events/hour at baseline to 2.3 events/hour during follow-up. Mean time in AF decreased from 5.0%-4.3% in the control group and from 5.6%-4.1% in the CPAP group, but the difference in change was not significant (p=0.52). Sub-analysis of those using CPAP><4 hours/night also showed no difference, neither did the quality of life questionnaires.

Conclusion

This is the first randomized controlled trial to assess the effect of treatment of SA on the burden of AF, and did not detect a difference between those treated with CPAP compared to usual care alone.

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): Oslo University Hospital is the main funding Source. ResMed Science Center provided an unrestricted grant.
Sinus heart rate post pulmonary vein ablation and long-term risk of recurrences
Authors: Von Olshausen G , Saluveer O , Schwieler J , Drca N , Bastani H , Tapanainen J , Bourke T , Paul-Nordin A , Kenneback G , Insulander P , Jensen-Urstad M , Braunschweig F
Published: November 2020

Aim

To investigate the association of sinus heart rate pre- and post-ablation and recurrence rates in patients undergoing catheter ablation for atrial fibrillation.

Methods

Between January 2012 and December 2017, data of 482 patients undergoing their first pulmonary vein isolation (PVI) were included. All patients were followed-up for 12 months and were screened for any atrial tachyarrhythmia. Sinus heart rate measurements were recorded before (PRE), directly post ablation (POST) and 3 months post ablation (3M).

Results

In the total study population, the mean resting sinus heart rate at PRE (mean 57.9 bpm (95% CI, 57.1–58.7 bpm)) increased by over 10 bpm to POST (mean 69.4 bpm (95% CI, 68.5–70.3 bpm); p<0.001) followed by a slight decrease at 3M (mean 67.3 bpm (95% CI, 66.4–68.2 bpm)) but still remaining higher compared to PRE (p<0.001). This pattern was observed in patients with and without recurrences at PRE, POST and 3M respectively (both p<0.001). However, only at 3M, there was a significant difference in mean heart rate being lower in patients with compared to patients without recurrences (p=0.031). In this regard, patients with a heart rate ≥60 bpm at 3M and a heart rate change ≥11 bpm (PRE to 3M) had a favorable outcome in terms of recurrences compared to the remaining patients (HR 0.61 (95% CI, 0.44–0.84), p=0.002 and HR 0.55 (95% CI, 0.40–0.76), p<0.001, respectively). These variables remained independently associated in multivariable analysis.

Conclusion

Our study confirms the impact of PVI on cardiac autonomic function with a significant heart increase post-ablation. A heart rate ≥60bpm at 3M and a heart rate change ≥11 bpm (PRE to 3M) are associated with a favorable outcome in terms of recurrences.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): German Research Foundation
Prevention of long-lasting atrial fibrillation through antitachycardia pacing in 584 dual-chamber pacemaker patients
Authors: Boriani G , Sakamoto Y , Iacopino S , Komura S , Pieragnoli P , Minamiguchi H , Infusino T , Noma T , De Rosa F , Takahashi Y , Biffi M
Published: November 2020

Background

Atrial fibrillation (AF) is a frequent arrhythmia in pacemaker patients and is associated with poor quality of life and increased risks of heart failure, dementia, stroke, and death. The MINERVA trial has shown that the combination of 3 pacing algorithms – 1) atrial antitachycardia pacing (aATP), 2) atrial preventive pacing and 3) managed ventricular pacing (MVP) - delays progression to persistent and permanent AF, compared with standard DDDR pacing mode and with MVP mode, in pacemaker patients with AF history.

Purpose

We performed a comparative non randomized evaluation to confirm the hypothesis that aATP is the main driver of persistent/permanent AF reduction independently on the effect of preventive atrial pacing.

Methods

Thirty-one Italian and Japanese Cardiology centers included consecutive dual-chamber pacemaker patients with AF history. aATP was programmed in all patients while preventive atrial pacing was not enabled. Comparison was made with all the 3 groups in MINERVA randomized trial. The main endpoint was incidence of AF longer than 7 consecutive days, as detected by device diagnostics.

Results

A total of 146 patients (73 years old, 54% male) were included and followed for a median observation period of 31 months. The 2-year incidence of AF>7 days was 12% in the aATP group, very similar to that found in the arm of the MINERVA trial with aATP enabled (13.8%, p=0.732) and significantly lower than AF incidence found in the MINERVA Control DDDR arm (25.8%, p=0.012) and in the MINERVA MVP arm (25.9%, p=0.025).

Conclusions

In a real-world population of dual-chamber pacemaker patients with AF history, use of aATP was associated with low incidence of persistent AF during follow up, highlighting that the positive results of the MINERVA trial are related to the effectiveness of aATP rather than to the effects of preventive atrial pacing.

Funding Acknowledgement

Type of funding source: None
Role of tilt-table testing in syncope diagnosis and management: analysis of patients referred to a syncope unit
Authors: Castelo A , Laranjo S , Lousinha A , Cunha P , Brandao C , Alves S , Silva A , Ferreira V , Bras P , Mano T , Oliveira M , Ferreira R
Published: November 2020

Introduction

Head-up tilt-testing (HUT) enables the reproduction of reflex syncope in a laboratory setting. Despite being used to confirm the diagnosis of this syncope, there is some concerns regarding the best protocol to use and recent studies with implantable loop recorders have called the value of HUT into question.

Aim

To characterize the population undergoing HUT according to the modified Italian protocol, type of response to HUT and subsequent management at our center in the last 4 years.

Methods

Retrospective analysis of consecutive P who underwent HUT between 2015 and 2018. Descriptive analysis of patients (P) demographics and medical history, indication for HUT, type of response to HUT and management.

Results

A total of 419P (55.1% female) were included with a mean age of 62 years. The majority (n=302, 72.1%) had comorbidities (structural heart disease – 55%, cardiac dysrhythmias – 57.6%, hypertension – 48.3%, diabetes – 15.6%, depression – 15.9%, cerebrovascular disease –10.6%) or was under medication (n=220, 52.5%) with a potential hypotensive or bradycardic effect (44.1% ACEI/ARA, 29.1% beta-blocker, 27.7% diuretic, 23.6% antidepressant, 22.7% calcium channel blocker, 19.1% benzodiazepines). Syncope/presyncope episodes accounted for 56.1% of the HUT, with falls and disequilibrium accounting for 52%. In 21 cases (5%) suspected dysautonomia or other non-specified reasons were the indication for HUT. HUT were ordered according to the guidelines in 136P (84.6% – indication level I, 3.6% – level IIa, 11.8% – level IIb). HUT was positive in 292P (69.7%) – 77.1% after nitroglycerin administration (vasodepressor – 170P, cardioinhibitory – 53P, mixed – 62P and dysautonomic – 7P). Cardioinhibitory (CI) response predominated in the younger, and vasodepressor in the older P. Of the P with CI response, 41.5% had asystole (median of 41.4s, minimum 7.5s, maximum 115s). All P were instructed in the need to avoid triggering factors and perform counterpressure maneuvers. A pacemaker was implanted in 24P (5.7% of all population, due to long sinus pauses and asystole). Twenty-four P (5.7%) completed a tilt training program.

Conclusion

Most of the HUT were requested for syncope/presyncope, frequently according to the guidelines. There was a high rate of positive tests, with a predominance of vasodepressive response, particularly in the elderly.

Funding Acknowledgement

Type of funding source: None
Efficiency and safety of his bundle pacing in patients with newly-acquired heart failure after long-term right ventricular pacing, results from China mainland
Authors: Yiheng Y.A.N.G , Kexin W.A.N.G , Yunlong X.I.A , Yingxue D.O.N.G
Published: November 2020

Background

Clinical outcomes of his bundle pacing (HBP) lead implantation in patients with pacing induced cardiomyopathy (PICM) are unknown. We aim to investigate the efficiency and safety of HBP upgrade in a single center.

Methods and results

Patients with PICM and indication of resynchronization therapy were selected during 2018.1–2019.12. Clinical data including parameters of echocardiographic examination, ECG measurements, New York Heart Association (NYHA) classification were assessed before and after HBP upgrade. HBP upgrade was fulfilled in 38 of 40 (95%) patients. During a mean of 9.36±5.63 months follow-up, 28 patients completed the follow-up of clinical data. The mean age was 67.86±12.85 years and men account for 67.9%. Mean of H-V interval was 56.86±7.11ms. Left ventricular ejection fraction (LVEF) significantly increased from baseline 32.75% to 44.19% (P<0.01). QRS duration decreased from 184.67±27.35 ms at baseline to 123.28±15.82ms with HBP (P<0.01). LVEDD remodeled reversed from 60.85 mm at right ventricular pacing (RVP) implantation to 53.16mm. NYHA functional class improved to 1.96 from 2.64 at baseline during follow-up (P<0.01). Over a median follow-up period of 3.03 (0.9–19.4) months, threshold of his bundle lead decreased from baseline 1.35±0.89mv to 1.2±0.89mv but no significance (P=0.308>0.05).

Conclusion

HBP significantly improved echocardiographic measurements and NYHA classification for those with PICM. The threshold of his bundle lead is relatively stable in our follow-up period, reminding that the HBP upgrade is safe and effective for PICM patients.

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): This study was supported by grants from Liaoning Clinical Capacity Construction Funding (LNCCC-D-20-2015).
Application of the ESC and AHA guidelines for admission of syncope patients presenting to the ED
Authors: Du Fay De Lavallaz J , Zimmermann T , Badertscher P , Flores D , Widmer V , Walter J , Strebel I , Lopez-Ayala P , Wussler D , Koechlin L , Di Somma S , Keller D , Kuehne M , Mueller C
Published: November 2020

Background

Syncope in the ED is linked with high diagnostic and prognostic uncertainty, leading to an extremely high rate of admissions. These often inappropriate admissions are costly and expose patients to unnecessary testing. The recent ESC and AHA guidelines aim at reducing these admissions by stratifying patients in high- and low-risk groups.

Methods

The BASEL IX Syncope study is a large prospective international multicenter study recruiting patients 40 years presenting to the ED with syncope within the last 12 hours in eight countries on three continents. Cardiac syncope was centrally adjudicated by two physicians using all data collected up to 1-y follow-up. We classified patients as requiring admission or being judged safe for discharge according to the ESC and AHA guidelines criteria and compared these with the physician's decision regarding hospitalization. We assessed the consequence of these decisions on 30-day serious cardiac events and mortality. We validated our findings in a large American cohort recruiting syncope patients >60 years in 11 EDs.

Results

1977 patients were eligible for this analysis. 215 (10.8%) experienced 30-day Major Adverse Cardiovascular Events (MACE). The ESC and AHA guidelines would have admitted a largely different number of patients (75.9% vs 29.6%) and provided different safety regarding adverse events and death at 30 days (Figure). The validation in the US cohort provided similar results, however US ED physicians decided to admit more patients (84%) as compared with the international derivation cohort (46.6%).

Conclusion

The AHA and ESC syncope guidelines recommend admission based on very different criteria and for a largely different number of patients. While the most recent ESC guidelines were written with the aim to limit the number of patients admitted, they still classify a large majority of an ED syncope cohort as high risk and warranting admission. The large discrepancy between the two guidelines is based on the criteria used for the classification: While the ESC guidelines consider risk factors, previous cardiac history, physical examination and ECG criteria, the AHA guidelines focus on serious conditions previously known or diagnosed in the ED. Figure: Percentage of the overall cohort admitted (green) or discharged (red) according to the AHA and ESC guidelines and to the decision of the physician in the BASEL-IX cohort. Patients experiencing a cardiac syncope, a 30-day MACE or death are represented for both the discharged and admitted groups.

Figure 1

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): University hospital Basel
Usefulness of late gadolinium enhancement cardiac magnetic resonance to predict appropriate therapies in implantable cardioverter defibrillator patients in primary prevention
Authors: Sanchez Somonte P , Quinto L , Zarakett F , Garre P , Alarcon F , Tolosana J.M , Guasch E , Arbelo E , Pujol M , Caixal G , Ortiz J.M , Jauregui B , Berruezo A , Mont L , Roca I
Published: November 2020

Background

The scar and the amount of border zone measured by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) has been proposed as an independent predictor of ventricular arrhythmias in patients with ischemic and non-ischemic cardiomyopathy. However, at the present time, the guidelines are based only on the ejection fraction to recommend an implantable cardioverter defibrillator (ICD) in primary prevention, and only a minority of these patients receive appropriate therapies. So, prevention needs to be improved.

Purpose

To identify predictors of appropriate therapies in patients with a primary prevention ICD using cardiac magnetic resonance imaging and a dedicated software (ADAS-3D) to characterize the scar.

Methods

Patients who underwent a LGE-MR prior to ICD implantation in primary prevention were retrospectively included. Clinical and cardiac imaging characteristics were collected. The myocardium was segmented with ADAS-3D software in 10 layers (from endocardium to epicardium). The scar, border zone, core and conducting channels were automatically measured in grams by the software.

Results

Since 2008 to 2017, 206 patients were included. Mean age was 67±28 years, 80% men, mean ejection fraction 26%±9, 52% with ischemic cardiomyopathy and 48% non-ischemic. The primary endpoint was appropriate therapies and/or sudden cardiac death (SCD). Median follow-up was 46.33 months. 46 patients (22%) reached the primary endpoint. Greater scar mass (36.05 grams vs 21.5 grams; HR 1.04; 95% CI (1.03–1-05), p<0.001), core mass (9.8 grams vs 5.6 grams; HR 1.06; 95% CI (1.04–1-09), p<0.001), border zone mass (26.2 grams vs 15.9 grams; HR 1.05; 95% CI (1.04–1-09), p<0.001) and channel mass (3.0 grams vs 1.6 grams; HR 1.15 95% CI (1.06–1.25), p<0.001) were associated with appropriate therapies and SCD. A border zone mass >5.3 grams was independently associated with the primary endpoint (HR: 4.77; 95% CI (1.15–19.73), p=0.03).

Conclusions

The amount of border zone, core and channel mass measured by LGE-MR and ADAS software are independent predictors of appropriate therapies and SCD in patients with ICD in primary prevention.

Scar characterization

Funding Acknowledgement

Type of funding source: None
Clinical outcomes and programming strategies of implantable cardioverter defibrillator (ICD) devices during childhood in hypertrophic cardiomyopathy: a UK national cohort study
Authors: Norrish G , Chubb H , Field E , McCleod K , Till J , Stuart G , Hares D , Linter K , Bhole V , Bowes M , Uzun O , Sadagopan S , Rosenthal E , Mangat J.P , Kaski J.P
Published: November 2020

Background

Sudden cardiac death (SCD) is the most common mode of death in childhood hypertrophic cardiomyopathy (HCM). ICDs have been shown to be effective at terminating malignant ventricular arrhythmias but at the expense of a high incidence of complications. The optimal device and programming strategies to reduce complications in this patient group are unknown.

Purpose

To describe the programming strategies and clinical outcomes of ICD implantation in childhood HCM.

Methods

Anonymised, non-invasive clinical data were collected from a retrospective, longitudinal multi-centre cohort of children (<16 years) with HCM (n=687) and an ICD in-situ from the United Kingdom.

Results

96 patients (61 male (64%), 6 non-sarcomeric (6%)) underwent ICD implantation at a median age 14yr (IQR 11–16, range 3–16) and weight 52.3 kg (IQR 34.8–63.1). Indication for ICD was primary prevention in 72 (75%). 82 (85%) had an endovascular system, 3 (3%) epicardial and 11 (12%) subcutaneous system. 61 patients (74%) were receiving one or more cardioactive medications at implantation [B blockers n=66, 70%, disopyramide n=14, 15%, amiodarone n=7, 7%, calcium channel blocker n=7, 9%, other n=5, 6%]. Programming practices varied: all had VF therapies activated (median 220bpm, IQR 212–230); 70 (73%) had a VT zone programmed (median rate 187 bpm, SD 20.9), of which 26 (27%) had therapies activated. 50 patients (61%) had antitachycardia pacing (ATP) activated. Over a median follow up of 53.6 months (IQR 27.3,108.4), 4 patients (4.2%) died following arrhythmic events despite a functioning device. 25 patients had 53 appropriate therapies (ICD shock n=47, ATP n=8), incidence rate 5.22 (95% CI 3.5–7.8). On univariable analysis, secondary prevention indication for ICD implantation was the only predictor of therapy [16 (64%) vs 8 (11.3%), p value <0.001]. 8 (8.3%) patients had 9 inappropriate therapies (ICD shock n=4, ATP n=5), incidence rate 1.37 (95% CI 0.65–2.8), caused by T wave oversensing (n=2), lead migration (n=1), supraventricular tachycardia (n=1). Device complications were seen in 30 patients (31%), including lead complications (n=16) and infection (n=10). No clinical characteristics predicted time to inappropriate therapy or lead complication.

Conclusions

In a contemporary cohort of children with HCM, the incidence of inappropriate therapies is lower than previously reported, yet complication rates remain higher than reported in adult patients. No clinical, device or programming strategies were associated with inappropriate therapies or lead complications.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): British Heart Foundation
Non-invasive electrical synchrony method to guide para-hisian stimulation implant technique
Authors: Logarzo E , Ortega D , Barja L , Paolucci A , Mangani N , Revollo G , Aboy J
Published: November 2020

Introduction

Right ventricular apex stimulation solves electrical disorder but electrical disynchrony can be generated. Left bundle branch block results in heart failure and device upgrade is needed in some cases. Para-hisian stimulation generates a physiological cardiac activation through normal conduction system. Sheaths and special leads are used with current techniques. We developed an implantation technique guided by non-invasive electric synchrony using conventional screw-in leads. Synchromax is a novel device used to evaluate non-invasive cardiac electrical synchrony. It is easy to understand, fast to obtain, non-invasive and reproducible. Synchromax was analyzed in previous studies and correlated with other methods.

Objective

Usefulness and safety of non-invasive cardiac electrical synchrony method using conventional screw-in leads to guide para-hisian device implantation.

Materials and methods

421 patients were evaluated. All patients had indication of ventricular stimulation (pacemaker and ICD). Non-invasive electrical synchrony was performed with Synchromax study during the device implantations in all patients. Synchrony index and curves were analyzed. Type 2 curve and index between 0,1 and 0,4 were considered synchronous. Type 8 curve and index more than 0.7 were considered dyssynchronous. Attempt numbers, thresholds, fluoroscopy time and dislodgments were analyzed.

Results

Mean age 69 years (±8 years). 67,9% males. 421 devices were implanted (334 pacemakes and 87 ICDs). Sick sinus syndrome was the main pacemaker aetiology and dilated cardiomyopathy was in patients with ICD. Conventional screw-in leads were used in all cases. An implant technique was designed. A J-shaped curve with a small perpendicular curve at the tip is performed in the stylet. On average 1,9 attempts were made. Thresholds average 1,2 mV. High thresholds in 4 patients with selective parahisian stimulation. 7 dislodgments was evidenced (1,6%). Fluoroscopy time average 8,4 min. Type 2 curve and index under 0,4 was obtained in 94,5% of cases.

Conclusions

Para-hisian pacemaker implantation guided by Synchromax method using conventional screw-in leads is safe and useful achieving a physiological stimulation. Few attempts were needed with this new technique. Thresholds were similar to those used in conventional technique.

Funding Acknowledgement

Type of funding source: None