Role of inducibility and its dynamic change in the outcome of catheter ablation of atrial fibrillation: a single center prospective study

BACKGROUND

The role of atrial arrhythmia inducibility as an endpoint of catheter ablation of atrial fibrillation (AF) has been a controversial subject in many studies. Our goal is to evaluate the significance of inducibility, the impact of multiple sites or protocols of stimulation or the change in inducibility status in a prospective study including patients with AF undergoing first catheter ablation.

METHODS

We studied 170 consecutive patients with AF (62.9% paroxysmal) undergoing catheter ablation. All patients underwent two separate stimulation protocols before and after the ablation from the coronary sinus ostium and the left atrial appendage: burst pacing at 300, 250, 200 milliseconds (or until refractoriness) for 10 seconds and ramp decrementing from 300 to 200 milliseconds in increments of 10 milliseconds every three beats for 10 seconds. Inducibility was defined as any sustained AF or organized atrial tachycardia (AT) lasting >30 seconds.

RESULTS

We had AF/AT inducibility in 55 patients at baseline compared to 36 following ablation. After a mean of 41, 3 months follow-up, 115 patients were free of AF. Inducibility before or after the ablation or change in inducibility status did not influence AF recurrence. There were no significant differences regarding paroxysmal or persistent patients with AF.

CONCLUSIONS

Non-inducibility of atrial arrhythmia or change in inducibility status following pulmonary vein (PV) isolation and substrate modification are not associated with long-term freedom from recurrent arrhythmia. Therefore, the use of induction of an endpoint in AF ablation is limited.

Catheter ablation of ventricular arrhythmias and in-hospital mortality: insights from the German-wide Helios hospital network of 5052 cases

AIMS

Catheter ablation (CA) of ventricular arrhythmias is one of the most challenging electrophysiological interventions with an increasing use over the last years. Several benefits must be weighed against the risk of potentially life-threatening complications which necessitates a steady reevaluation of safety endpoints. Therefore, the aims of this study were (i) to investigate overall in-hospital mortality in patients undergoing such procedures and (ii) to identify variables associated with in-hospital mortality in a German-wide hospital network.

METHODS AND RESULTS

Between January 2010 and September 2018, administrative data provided by 85 Helios hospitals were screened for patients with main or secondary discharge diagnosis of ventricular tachycardia (VT) or premature ventricular contractions (PVCs) in combination with an arrhythmia-related CA using ICD- and OPS codes. In 5052 cases (mean age 60.9 ± 14.3 years, 30.1% female) of 30 different hospitals, in-hospital mortality was 1.27% with a higher mortality in patients ablated for VT (1.99%, n = 2, 955) compared to PVC (0.24%, n = 2, 097, P < 0.01). Mortality rates were 2.06% in patients with ischaemic heart disease (IHD, n = 2, 137), 1.47% in patients with non-ischaemic structural heart disease (NIHD, n = 1, 224), and 0.12% in patients without structural heart disease (NSHD, n = 1, 691). Considering different types of hospital admission, mortality rates were 0.35% after elective (n = 2, 825), 1.60% after emergency admission/hospital transfer <24 h (n = 1, 314) and 3.72% following delayed hospital transfer >24 h after initial admission (n = 861, P < 0.01 vs. elective admission and emergency admission/hospital transfer <24 h). In multivariable analysis, a delayed hospital transfer >24 h [odds ratio (OR) 2.28, 95% confidence interval (CI) 1.59-3.28, P < 0.01], the occurrence of procedure-related major adverse events (OR 6.81, 95% CI 2.90-16.0, P < 0.01), Charlson Comorbidity Index (CCI, OR 2.39, 95% CI 1.56-3.66, P < 0.01) and its components congestive heart failure (OR 8.04, 95% CI 1.71-37.8, P < 0.01), and diabetes mellitus (OR 1.59, 95% CI 1.13-2.22, P < 0.01) were significantly associated with in-hospital death.

CONCLUSIONS

We reported in-hospital mortality rates after CA of ventricular arrhythmias in the largest multicentre, administrative dataset in Germany which can be implemented in quality management programs. Aside from comorbidities, a delayed hospital transfer to a CA performing centre is associated with an increased in-hospital mortality. This deserves further studies to determine the optimal management strategy.

Incidence and characteristics of ventricular tachycardia in patients after percutaneous coronary revascularization of chronic total occlusions

Objectives

This study sought to investigate the prevalence of ventricular tachycardia after percutaneous coronary intervention (PCI) of chronic total occlusion (CTO).

Background

PCI of a CTO is associated with improvement of the left ventricular ejection fraction and possibly associated with reduced mortality. However, benefits of CTO-PCI must be weighed against a higher risk of procedure-related complications. The incidence of new-onset ventricular tachycardia after a successful CTO-PCI has not been investigated so far. In this retrospective registry we seek to describe characteristics and predictors of occurrence of post-procedural ventricular tachycardias.

Methods and results

Between 2010 and 2015, 485 patients underwent successful CTO-PCI at Heart Center Leipzig. Of them, 342 had complete follow-up and were further analyzed. Ventricular tachycardias were detected in 9 (2.6%) patients. All of them were monomorphic ventricular tachycardias occurring in median 1 day (interquartile range [IQR] 0.25–4.75 days) after PCI and caused prolongation of the hospital stay. Patients with ventricular tachycardia were older, had worse left ventricular ejection fraction (mean 33.1%, SD 5.9%) and more frequently a CTO of an infarct-related artery. The target vessel was not associated with the occurrence of ventricular arrhythmias. In multivariable analysis, only impaired left ventricular systolic function was an independent predictor for procedure-related ventricular tachycardia. Mortality rates were not different between patients with or without ventricular tachycardia.

Conclusion

Ventricular tachycardia can occur early after CTO-PCI as possible reperfusion arrhythmia and poorer left ventricular ejection fraction is the only independent predictor for onset. Although the occurrence of ventricular tachycardia after CTO-PCI seems not to influence mortality, awareness of this possible complication and longer monitoring may be recommended.

Acquired Pulmonary Vein Stenosis After Radiofrequency Ablation for Atrial Fibrillation: Single-Center Experience in Catheter Interventional Treatment

OBJECTIVES

The aim of the present study was to analyze and report a single-center experience with catheter interventional treatment of radiofrequency-induced pulmonary vein stenosis (PVS) following atrial fibrillation (AF) ablation.

BACKGROUND

Catheter interventional treatment of radiofrequency-induced PVS following AF ablation remains a challenging field because of a lack of randomized data and treatment guidelines.

METHODS

All patients at a single center who underwent catheter interventional treatment for radiofrequency-induced PVS were retrospectively assessed.

RESULTS

From January 2004 to September 2017, the total rate of PVS following interventional AF ablation was 0.78% (87 of 11,103). Thirty-nine patients with PVS were treated with 84 catheter interventions: 68 (81%) with percutaneous transluminal balloon angioplasty (PTA) and 16 (19%) with stent implantation. The distribution of stent type was 3 drug-eluting stents (19%) and 13 bare-metal stents (81%). The overall restenosis rate was 53% after PTA versus 19% after stent implantation (p = 0.007) after a median follow-up period of 6 months (interquartile range: 3 to 55 months). The total complication rate for PTA was 10% versus 13% for stenting (p = NS).

CONCLUSIONS

This study demonstrates significantly better outcomes in terms of restenosis after stent implantation versus PTA only, with comparable complication rates for these 2 options of interventional treatment of radiofrequency-induced PVS. In summary, despite the lack of randomized studies, the present data and currently available published studies seem to favor stent implantation as a first-line therapy in patients with radiofrequency-induced severe PVS.

Combined single-session cardiovascular magnetic resonance: stress perfusion and three-dimensional pulmonary vein angiography for stratification of atrial fibrillation patients with chest pain syndromes prior to catheter ablation

Aims 

To determine the clinical utility of a combined single-session cardiovascular magnetic resonance (CMR) imaging protocol integrating adenosine stress perfusion and three-dimensional pulmonary vein angiography for stratification of atrial fibrillation (AF) patients referred for pulmonary vein isolation (PVI) and complaining about chest pain syndromes.

Methods and results 

The preprocedural CMR examination (adenosine stress perfusion, late gadolinium enhancement, and three-dimensional pulmonary vein angiography) was performed in 357 consecutive AF patients with chest pain syndromes referred for PVI. Stress perfusion results were used for stratification: ischaemia positive patients underwent invasive coronary angiography, ischaemia negative patients underwent PVI, and follow-up/outcome data were collected (combined primary endpoint of cardiac death/non-fatal myocardial infarction). The integrated CMR protocol had a high success rate (356/357, 99.7%), a short total examination duration (<30 min in all patients), and delivered high-quality three-dimensional pulmonary vein angiography in all patients undergoing PVI (324/324, 100%). Variants of pulmonary vein anatomy were identified in 33% of all patients (117/357). Stress positivity (28/356, 8%) had a high positive predictive value for identification of obstructive coronary artery disease (86%), while stress negativity carried a low short-term event rate following PVI (cumulative 1-year event-free survival rate, 99.6%).

Conclusion 

Combined single-session CMR as a routine diagnostic workup for AF patients with chest pain syndromes prior to PVI proved to represent a time-efficient and effective stratification tool.

Agreement between gadolinium-enhanced cardiac magnetic resonance and electro-anatomical maps in patients with non-ischaemic dilated cardiomyopathy and ventricular arrhythmias

AIMS

We sought to investigate the overlap between late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR) and electro-anatomical maps (EAM) of patients with non-ischaemic dilated cardiomyopathy (NIDCM) and how it relates with the outcomes after catheter ablation of ventricular arrhythmias (VA).

METHODS AND RESULTS

We identified 50 patients with NIDCM who received CMR and ablation for VA. Late gadolinium enhancement was detected in 16 (32%) patients, mostly in those presenting with sustained ventricular tachycardia (VT): 15 patients. Low-voltage areas (<1.5 mV) were observed in 23 (46%) cases; in 7 (14%) cases without evidence of LGE. Using a threshold of 1.5 mV, a good and partially good agreement between the bipolar EAM and LGE-CMR was observed in only 4 (8%) and 9 (18%) patients, respectively. With further adjustments of EAM to match the LGE, we defined new cut-off limits of median 1.5 and 5 mV for bipolar and unipolar maps, respectively. Most VT exits (12 out of 16 patients) were found in areas with LGE. VT exits were found in segments without LGE in two patients with VT recurrence as well as in two patients without recurrence, P = 0.77. In patients with VT recurrence, the LGE volume was significantly larger than in those without recurrence: 12% ± 5.8% vs. 6.9% ± 3.4%; P = 0.049.

CONCLUSIONS

In NIDCM, the agreement between LGE and bipolar EAM was fairly poor but can be improved with adjustment of the thresholds for EAM according to the amount of LGE. The outcomes were related to the volume of LGE.

First-principles study of phase stability, electronic and mechanical properties of plutonium sub-oxides

The formation energies (ΔH_f) of fluorite PuO₂, α-Pu₂O₃ and sub-oxides PuO_2-x (0.0 < x < 0.5) are determined from atomic scale simulations based on density functional theory (DFT) employing the generalised gradient approximation (GGA) corrected with an effective Hubbard parameter (U_eff). The variation of structural and electronic properties of PuO₂ and α-Pu₂O₃ is determined while ramping up U_eff from 0 eV to 5 eV (U_eff-ramping method) to treat the presence of metastable magnetic states and to determine the most suitable U_eff value matching the experiments. The GGA+U calculated lattice parameter variation as a function of stoichiometry (a(x)) for PuO_2-x shows a positive volume of relaxation and an almost linear variation presented by the relation a(x) = a₀- 0.522738x, where a₀ is the equilibrium lattice parameter of PuO₂. The GGA+U calculated ΔH_f values of PuO_2-x lie above the tie line connecting the ΔH_f of PuO₂ and Pu₂O₃, and with decreasing O/Pu ratio, the stability of the sub-oxides increases. The crystal and electronic structure analysis of the oxygen vacancy in PuO₂ shows outward anisotropic relaxation of four Pu atoms around the vacancy site. The electronic charges within the Wigner-Seitz sphere around these Pu atoms show an overall gain of only (0.12-0.22)e per Pu atom, signifying an incomplete localization of charges. Finally, the GGA+U calculated single crystal elastic constant values decrease continuously with decreasing O/Pu ratio from 2.0 to 1.5. The rate of decrease of the average C₁₁ is almost 11-15 times higher compared to the rate of decrease of C₁₂ and C₄₄.

Effect of Exercise on Outcome after Ventricular Tachycardia Ablation in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

Competitive sports and intensive exercise are associated with adverse outcomes in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). This study aimed to assess the role of exercise on long-term results of radiofrequency catheter ablation (RFCA) therapy of ventricular tachycardia (VT) in patients with ARVD/C. Exercise participation was evaluated by telephone or in-person interviews in patients from our ARVD/C registry with previous VT ablation (38 patients, 26 males, age 52.6±14.1years). Of 38 patients, 30 were involved in sports activities before RFCA. Only the minority of our patient population (21.1%) had a sedentary lifestyle before RFCA; 42.1 and 36.8% reported recreational or competitive sports, respectively. During the follow-up period of 52.5±31.4 months, 23 of the total 38 patients with previous RFCA (60.5%) remained free from VT recurrence. In univariate and binary logistic regression analysis, only advanced age was significantly associated with VT recurrence, with a hazard ratio of 1.15, and 95% confidence interval 1.05-1.26 (p=0.004). The results of our observational study indicate that recreational sports do not impair long-term results after RFCA treatment compared with a sedentary lifestyle. Furthermore, the dynamic component of recreational exercise did not affect the outcome of VT ablation in our patient population. Recreational exercise at low to moderate intensity is not associated with an increased risk for VT recurrence after catheter ablation in patients with ARVD/C.

Natural course of acquired pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation-Is routine follow-up imaging indicated or not?

INTRODUCTION

Thermal injury during radiofrequency ablation (RFA) of atrial fibrillation (AF) can lead to pulmonary vein stenosis (PVS). The aim of the present study was to analyze the natural course of RFA-induced PVS with regard to the grade of stenosis, clinical symptoms, and mortality during long-term follow-up.

METHODS AND RESULTS

All patients with follow-up imaging for radiofrequency-induced untreated PVS were retrospectively assessed. From 2004 to 2017, the total rate of PVS following AF ablation in our center was 0.78% (87 of 11 103). Thirty-eight patients with a total of 54 untreated PVS underwent follow-up including imaging scan. The mean degree of stenosis at the time of diagnosis was 57% ± 27% vs 45% ± 35% (P = .05) after a mean follow-up of 43 ± 31 months. There was a shift in severity of the PVS: 18 of 54 (33%) vs 16 of 54 (30%) severe PVS, 19 of 54 (35%) vs 10 of 54 (18%) moderate PVS, and 17 of 54 (32%) vs 28 of 54 (52%) mild PVS (P = .0001). The mean symptom score decreased significantly during follow-up (1.8 ± 1.0 vs 0.4 ± 0.5, P = .0001). Each of the four patients with progression of PVS underwent another pulmonary vein isolation for AF recurrence following pulmonary vein reconduction during follow-up period.

CONCLUSION

This study showed a spontaneous reduction in stenosis grade and symptoms of PVS over a 3.5-year follow-up. Consequently, routine follow-up imaging of PVS seems not to be necessary. However, additional RF energy delivery to stenotic pulmonary veins should be avoided if possible. In case of conduction recovery, the ablation line should be done wide-antrally and follow-up imaging of PVS is recommended.

Impact of olive oil and honey on healing of diabetic foot: a randomized controlled trial

Background: This study aimed 1) to examine the impact of honey on diabetic foot; 2) to examine the effect of olive oil on diabetic foot; and 3) to compare the impact of honey and olive oil in the healing of diabetic foot.

Methods: In this randomized controlled trial, 45 patients took part. Patients were randomly assigned to three groups. In the honey group, the wound was dressed using gauzes with honey daily for 1 month. In the olive oil group, the wound was dressed using gauzes with olive oil (4 mL) daily for 1 month. Patients in the control group received usual dressing. Wounds were assessed before and after intervention using the Wagner scoring system and the checklist of diabetic foot healing (where a higher score indicates better wound healing).

Results: Demographic characteristics of patients in the three groups were similar. Mean scores of tissue around the wound, wound grade, wound drainage, and wound healing were similar before intervention in all three groups. After intervention, means score of tissue around the wound, wound grade, wound drainage, and wound healing were significantly higher in patients in the honey and olive oil groups compared to patients in the control group.

Conclusion: The results of this study reveal that honey is as effective as olive oil in the treatment of diabetic foot. Given the few studies on this topic, further investigation is needed.

Time-dependent prediction of arrhythmia recurrences during long-term follow-up in patients undergoing catheter ablation of atrial fibrillation: The Leipzig Heart Center AF Ablation Registry

The prediction of arrhythmia recurrences after catheter ablation of atrial fibrillation (AF) remains challenging. The aim of current analysis was to investigate the time-dependent prediction of arrhythmia recurrences after AF catheter ablation during long-term follow-up. The study included 879 patients (61 ± 10 years; 64% males; 39% persistent AF) undergoing first AF catheter ablation. Rhythm outcomes were documented using 7-days Holter monitoring. The APPLE score (Age, Persistent AF, imPaired eGFR, Left atrium (LA), EF) was calculated at baseline, while MB-LATER score (Male gender, Bundle branch block, LA, AF Type, Early Recurrences) 3 months after ablation. The median follow-up time was 37 months [95%CI 35;39]. ERAF and LRAF occurred in 45% and 64%, respectively. On multivariable analysis, ERAF (HR 2.095, 95%CI 1.762–2.490, p < 0.001) was strongly associated with LRAF. The APPLE (HR 1.385, 95%CI 1.276–1.505, p < 0.001) and MB-LATER (HR 1.326, 95%CI 1.239–1.419, p < 0.001) scores significantly predicted LRAF during follow-up. On the ROC analysis, APPLE (AUC 0.640, 95%CI 0.602–0.677, p < 0.001) and MB-LATER (AUC 0.654, 95%CI 0.616–0.691, p < 0.001) demonstrated moderate prediction. Summarizing, ERAF was the strongest predictor for LRAF in time-dependent manner. The APPLE and MB-LATER scores demonstrated moderate prediction of arrhythmia recurrences during long term follow-up.

Is epicardial fat tissue associated with atrial fibrillation recurrence after ablation? A systematic review and meta-analysis

INTRODUCTION

Although an undoubted association between epicardial fat tissue (EFT) and atrial fibrillation (AF) has been recently approved, the association between EFT and post-ablation AF recurrence is not evident yet. This study aimed to assess the association between EFT and AF recurrence after ablation.

METHODS

The present study was a systematic review and meta-analysis using related literature available in electronic databases until July 2018 via "atrial fibrillation" and "epicardial fat" as the main keywords. Considering the different methods of EFT measurement, three different pooled meta-analyses were conducted in this study including: 1) comparison of total EFT volume, 2) left atrium (LA)-EFT volume, and 3) EFT thickness between two groups with and without AF recurrence estimating standardized mean difference (SMD) through a random and non-random effect meta-analysis. Statistical analysis was also performed using Comprehensive Meta-analysis (CMA) Software.

RESULTS

Following a search into a total number of 518 articles, the findings of 12 studies published in 10 articles were enrolled in this meta-analysis. Accordingly, the results of meta-analysis showed that LA-EFT and total EFT volumes were higher in recurrent subjects (LA-EFT: SMD = 0.862 ml; I2 = 0.00, 95% confidence interval (CI) = 0.567-1.156; total EFT: SMD = 1.017 ml, I2 = 0.00, 95% CI = 0.748-1.286). Besides, a significant higher EFT thickness in patients with AF recurrence compared to those with no AF recurrence was observed (SMD = 0.808 mm, I2 = 91.07, 95% CI = 0.215-1401).

CONCLUSION

The total EFT and LA-EFT volumes, as well as EFT thickness, seemed to be associated with AF recurrence in patients undergoing AF ablation.

Sleep Disorders and Atrial Fibrillation: Current Situation and Future Directions

Atrial fibrillation (AF) is a growing health problem worldwide. In recent years, there has been a rising interest in the relationship between sleep disorders and AF. Several studies have reported higher prevalence and incidence rates of AF in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). However, some believe that OSAHS is not a risk factor for AF; but AF, by itself, is regarded as one of the possible triggers for OSAHS. In this study, the related literature investigating the association between OSAHS and AF was reviewed, and then the possible mechanisms of this interplay were discussed. To conclude, recommendations for further research in this field were presented to researchers and some points were highlighted for physicians.

Exercise and Atrial Fibrillation: Some Good News and Some Bad News

Atrial fibrillation (AF) is considered as the most common sustained arrhythmia in adults, whose incidence rate is on the rise due to the increase in the mean age of the global population. In recent years, many efforts have been made to identify effective factors in the incidence of AF to prevent them and thereby reduce the consequences of AF. Physical activity is one of the topics that attracted much attention in the last two decades. According to some findings, extreme and prolonged exercise itself can be considered as a risk factor for the onset of AF; however, other studies have shown that exercise can be regarded a protective factor against AF in the general population. The present study reviews the findings of studies on the relationship between AF and exercise and discusses possible mechanisms for this relationship. Additionally, we present some recommendations for researchers and physicians about exercise management in association with AF prevention.

Characteristics of the ablation lesions in cardiac magnetic resonance imaging after radiofrequency ablation of ventricular arrhythmias in relation to the procedural success

BACKGROUND

In human patients, studies about the cardiac magnetic resonance (CMR) appearance of the acute radiofrequency (RF) lesions in relation to the procedural outcomes after catheter ablation (CA) of ventricular arrhythmias (VA) are scarce. We aimed to investigate the RF lesions characteristics in relation to the procedural success.

METHODS

Patients referred for ablation of VA received CMR (1.5 T) using gadolinium contrast before and after ablation. CA in left ventricle was performed using a 3.5-mm irrigated catheter. The volume and transmurality of the RF-induced lesions were measured in early gadolinium-enhanced postablation CMRs. Acute failure was defined as persistently inducible VA at the end of the CA.

RESULTS

Twenty-five patients (60.7 ± 9.8 years, 19 with sustained ventricular tachycardia) were studied. All RF lesions had nonenhanced core. The volume of the nonenhanced lesions showed positive correlation with the maximal RF power (r = 0.598, P = .002) and the impedance drop (r = 0.416, P = .038). Patients with transmural (≥75%) lesions had significantly larger impedance drop as compared to those with nontransmural lesions (<75%): 20.3 ± 9.4 versus 13.5 ± 4.3, P = .037. In the failures, the lesions volume was nonsignificantly larger: 3.86 ± 3.3% versus 2.6 ± 1.7%, P = .197; however, it was considerably deeper: 86 ± 13% versus 62 ± 26%, P = .03.

CONCLUSIONS

CMR after VA ablation showed nonenhanced lesions resembling the no-reflow phenomenon in myocardial infarction. Although the size and the depth of the RF injury correlated with the ablation energy and impedance drop, they were not associated with acute ablation success.

Catheter ablation of atrial fibrillation with nonfluoroscopic catheter visualization-a prospective randomized comparison

PURPOSE

The application of a novel platform for nonfluoroscopic catheter sensor tracking within pre-recorded x-ray loops in the context of catheter ablation of atrial fibrillation (AF) demonstrated significant potential for reduction of fluoroscopy. We sought to provide the first prospective randomized comparison of fluoroscopy needs, procedure times, and complications in AF catheter ablation with or without additional use of nonfluoroscopic catheter visualization (NFCV).

METHODS

Patients with AF were randomized into two groups before scheduled radiofrequency ablation: (1) using established mapping systems and fluoroscopy as needed (CONV group) or (2) with additional NFCV (NFCV group). All procedures were performed in the same lab using the same ablation catheter tip technology and the same mapping and ablation strategies. Primary endpoints were radiation time and dose. Secondary endpoints were procedural parameters, complications, and long-term success.

RESULTS

A total of 80 patients (48 male patients, mean age 60 years, 46 patients with paroxysmal AF) were randomized into the two groups. Clinical parameters between both groups were similar. NFCV use reduced mean fluoroscopy time (1.9 vs. 13.2 min, p < 0.001) and mean dose (510 vs. 1549 Gycm², p < 0.001) significantly. Procedural parameters were similar in the two groups. One conservatively treated groin complication occurred (1.3%).

CONCLUSIONS

Radiation exposure can be significantly reduced by using the novel NFCV technology in addition to standard AF ablation technologies without negative effects on procedure durations, success rates, or complication rates. With the use of the technology, abandonment of lead protection for EP staff is possible following transseptal puncture.

Prediction of electro-anatomical substrate and arrhythmia recurrences using APPLE, DR-FLASH and MB-LATER scores in patients with atrial fibrillation undergoing catheter ablation

Arrhythmia recurrences after catheter ablation of atrial fibrillation (AF) cause intensive treatment costs. Left atrial electro-anatomical remodeling measured as low voltage areas (LVA) during catheter ablation indicates advanced disease stage and is associated with poor ablation success. The aim of this study was to analyze the prediction of LVA and arrhythmia recurrences using APPLE, DR-FLASH and MB-LATER scores. APPLE, DR-FLASH scores were calculated at baseline and MB-LATER at 3 months post-ablation in AF patients undergoing first catheter ablation. LVA was determined using high-density maps and defined as <0.5 mV. Early (ERAF, <3 months) and late (LRAF, 3–12 months) were analyzed during follow-up. The study population included 241 patients (age 64 ± 11 years, 59% males, 59% persistent AF, 27% LVA, 27% LRAF). LVA were significantly associated with recurrences (OR 2.081, p = 0.026). While on univariable analysis, all scores were significantly associated with LVA, on multivariable analysis only APPLE (OR 1.789, p < 0.001) and DR-FLASH (OR 2.144, p < 0.001) remained significant predictors. However, MB-LATER (OR 1.445, p = 0.034) and ERAF (OR 5.078, p < 0.001) remained associated with LRAF on the multivariable analysis. These results were validated in a subgroup of 873 patients (age 61 ± 10, 63% males, 39% persistent AF, 34% LRAF, 27% LVA) from The Leipzig Heart Center AF Ablation Registry. All scores were significantly associated with recurrences. However, ERAF was the most powerful predictor for later rhythm outcomes. Summarizing, a clinical score useful for prediction for both LVA and rhythm outcomes in AF patients remains a clinical unmet need.