Impact of pulmonary vein anatomy and ostial dimensions on long-term outcome after single-shot device-guided cryoablation for paroxysmal atrial fibrillation

BACKGROUND

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). This observational study aimed to assess the role of individual anatomical characteristics to predict long-term freedom from arrhythmia recurrence after CB-guided PVI for paroxysmal AF (PAF).

METHODS

Three hundred fifty three consecutive patients (58 ± 11 years, 56% males), undergoing PVI between 2012 and 2018 were analysed. Individual pulmonary vein (PV) anatomy was assessed using preprocedural cardiac magnetic resonance imaging (MRI). For each PV, the cross-sectional area (CSA) was calculated. The impact of PV characteristics and CSA on long-term AF-free survival was evaluated.

RESULTS

Acute PVI was achieved in all patients. Two hundred twenty-three patients (63%) had a normal PV anatomy (2 left- and 2 right-sided PV). Variant PV anatomy was present in 130 patients (37%). During the observation period of 48 months, AF-recurrence was documented in 167 patients (47 %). Patients with AF-recurrence presented with significantly enlarged right-sided PVs and left superior PVs (LSPVs) (p < 0.001). The presence of left common PVs (LCPVs) (n = 75, Log-rank p < 0.001) as well as right variant PVs (n = 35, Log rank p < 0.001) was associated with a significantly impaired long-term AF-free survival rate as compared to patients with normal PV characteristics.

CONCLUSION

Variant PV anatomy is a good predictor for AF-recurrence. A correlation between an enlarged CSA of right-sided PVs as well as LSPVs and AF-recurrence was documented.

First clinical experience using a novel automated mapping algorithm for mapping of ventricular arrhythmias

A new automated vector-based mapping algorithm (AMA) for 3-dimensional (3D) mapping has been introduced. The aim of this study was to present our experience using AMA to recognize additional catheter ablation targets in patients with ventricular arrhythmias (VA). A total of 16 patients (ICM; ischemic cardiomyopathy, n = 6; NICM; non-ischemic cardiomyopathy n = 10) suffering from VA underwent catheter ablation. Following bipolar voltage mapping, AMA was utilized to reveal zones of decelerated conduction velocity vectors (CVV) and this information was superimposed onto the 3D reconstructions and compared with the presence of scar. Mapping time was 28.1 ± 10 min for the endocardial reconstruction of the left ventricle (LV) and 17 ± 5.4 min for the epicardium (n = 6 patients). The mean area of LV low voltage was 13.9 ± 15% (endocardial) and 11.9 ± 5.7% (epicardial). Decelerating CVV zones were revealed in all patients (mean conduction velocity threshold of 39.3 ± 13%). Sustained VA have been terminated through ablation and substrate modification was performed in all patients. Correlation between the presence of CVV deceleration zones and areas of abnormal low voltage from bipolar mapping was revealed in only 37.5% of patients, but there was good correlation between scar from unipolar voltage mapping and the presence of CCV deceleration zones (94%; p = 0.008). The novel AMA may improve the understanding of individual VA substrates due to the visualization of decelerated CVV zones and their correlation with abnormal low voltage predominantly from unipolar mapping.

The Role of Daily Implant-Based Multiparametric Telemonitoring in Patients with a Ventricular Assist Device

The telemonitoring of heart failure (HF) patients is becoming increasingly important. This study aimed to evaluate the benefit of telemonitoring in end-stage HF patients with a ventricular-assistance device (VAD). A total of 26 HF-patients (66 ± 11 years, 88% male) on VAD therapy with an implantable cardioverter-defibrillator (ICD) or a cardiac resynchronization defibrillator (CRT-D) including telemonitoring function were enrolled. The long-term follow-up data (4.10 ± 2.58 years) were assessed. All the patients (n = 26, 100%) received daily ICD/CRT-D telemonitoring. In most of the patients (73%, n = 19), the telemedical center had to take action for a mean of three times. An acute alert due to sustained ventricular arrhythmias (VAs) occurred in 12 patients (63%) with 50% of them (n = 6) requiring ICD shock delivery. Eight patients (67%) were hospitalized due to symptomatic VAs. In 11 patients (92%), immediate medication adjustments were recommended. Relevant lead issues were revealed in thirteen patients (50%), with six patients (46%) undergoing consecutive lead revisions. Most of the events (83%) were detected within 24 h. Daily telemonitoring significantly reduced the number of in-hospital device controls by 44% (p < 0.01). The telemonitoring ensured that cardiac arrhythmias and device/lead problems were identified early, allowing pre-emptive and prompt interventions. In addition, the telemonitoring significantly reduced the number of in-hospital device controls in this cohort of HF patients.

EASY-WPW: a novel ECG-algorithm for easy and reliable localization of manifest accessory pathways in children and adults

AIMS

Accessory pathway (AP) ablation is a standard procedure for the treatment of Wolff-Parkinson-White syndrome (WPW). Twelve-lead electrocardiogram (ECG)-based delta wave analysis is essential for predicting ablation sites. Previous algorithms have shown to be complex, time-consuming, and unprecise. We aimed to retrospectively develop and prospectively validate a new, simple ECG-based algorithm considering the patients' heart axis allowing for exact localization of APs in patients undergoing ablation for WPW.

METHODS AND RESULTS

Our multicentre study included 211 patients undergoing ablation of a single manifest AP due to WPW between 2013 and 2021. The algorithm was developed retrospectively and validated prospectively by comparing its efficacy to two established ones (Pambrun and Arruda). All patients (32 ± 19 years old, 47% female) underwent successful pathway ablation. Prediction of AP-localization was correct in 197 patients (93%) (sensitivity 92%, specificity 99%, PPV 96%, and NPV 99%). Our algorithm was particularly useful in correctly localizing antero-septal/-lateral (sensitivity and specificity 100%) and posteroseptal (sensitivity 98%, specificity 92%) AP in proximity to the tricuspid valve. The accuracy of EASY-WPW was superior compared to the Pambrun (93% vs. 84%, P = 0.003*) and the Arruda algorithm (94% vs. 75%, P < 0.001*). A subgroup analysis of children (n = 58, 12 ± 4 years old, 55% female) revealed superiority to the Arruda algorithm (P < 0.001*). The reproducibility of our algorithm was excellent (ϰ>0.8; P < 0.001*).

CONCLUSION

The novel EASY-WPW algorithm provides reliable and accurate pre-interventional ablation site determination in WPW patients. Only two steps are necessary to locate left-sided AP, and three steps to determine right-sided AP.

Impact of pulmonary vein variant anatomy and cross-sectional orifice area on freedom from atrial fibrillation recurrence after cryothermal single-shot guided pulmonary vein isolation

BACKGROUND

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). This study aimed to evaluate ablation efficacy and freedom from arrhythmia recurrence using the novel POLARx compared to the Arctic Front Advance Pro (AFA) CB system including the analysis of individual PV characteristics.

METHODS

A total of 687 patients underwent CB-guided ablation for AF. Arrhythmia recurrence was defined as an ECG documented episode of any AF/atrial tachycardia (AT) > 30 s. Anatomical characteristics were assessed using magnetic resonance imaging (MRI). For each PV, the cross-sectional orifice area (CSOA) was determined. Follow-up examinations were scheduled after 3, 6, and 12 months.

RESULTS

Acute PVI was achieved in all patients. Twelve-month AF-free survival was similar between the groups (POLARx 43/86 (50%) vs. AFA 318/601 (53%), Log-rank (LR) p = 0.346). MRI found a comparable percentage of patients with normal PV anatomy (POLARx 71/86 (83%) vs. AFA 530/601 (85%), p = 0.162). Patients with variant PV characteristics presented with a significantly impaired 12-month AF-free survival (normal PVs 326/585 (56%) vs. variant PVs 27/102 (27%), LR p < 0.001) independent of the applied CB ablation system. PAF patients with AF recurrence presented with significantly larger CSOA of the left-sided PVs and the right superior PVs (LSPV: p < 0.001; LIPV: p < 0.001; RSPV: p < 0.001). In PERS AF, no association between CSOA and ablation outcome was observed. Multivariate analyses identified PERS AF (hazard ratio (HR) 2.504, confidence interval (CI), 1.900-3.299, p < 0.001) and variant PV anatomy (HR 2.124, CI 1.608-2.805, p < 0.001) as independent predictors for AF recurrence.

CONCLUSIONS

Both CB ablation systems are associated with comparable 12-month AF-free survival rates. Variant PV anatomy seems to be predictive for AF recurrence. An association between CSOA and the outcome after CB-guided PVI was demonstrated for PAF.

Fifty-fifty - a comparison of two 50 watts high power short duration protocols using temperature- versus power- controlled radiofrequency ablation for atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Radiofrequency-guided catheter ablation (RFCA) is an established treatment option for atrial fibrillation (AF). New approaches applying higher than usual energy levels for shorter periods (high power short duration, HPSD) to improve lesion quality have been reported. The novel DiamondTemp (DT) catheter allows for temperature-guided high power RFCA. Data on a direct comparison of the two emerging RFCA approaches are lacking.

Purpose

This observational single center study aimed to compare the efficacy, safety and characteristics of the novel DT catheter to an ablation index (AI) guided 50 W high power short duration (HPSD) ablation protocol using a conventional force-sensing equipped ablation catheter with surround-flow.

Methods

A total number of 101 patients undergoing RFA for AF were included. 33 patients treated with the DT catheter (50 W, 9 sec), were compared to 69 consecutive patients undergoing AI-guided AF ablation (AI anterior 550; AI posterior 400) with an open-irrigated catheter adherent to a 50 W HPSD protocol. Procedural data and recurrence rates were documented. Follow-up examinations were scheduled after 3, 6 and 12 months.

Results

Acute procedural success was achieved in all patients (n=101, 100%). DT-guided AF ablation was associated with a significantly longer mean procedure duration (98.8±30.1min vs. 78.2±25.6, p=0.002*). PVI using the DT ablation catheter required significantly more RF applications (75.4±30.8min vs. 61.3±14.1, p=0.019*). Total RF duration was significantly lower in the DT group (792.1±311.2sec vs. 1035.5±287.2sec, p&lt;0.001*) as well as fluoroscopy time (4.6±2.1min vs.5.5±2.5min, p&lt;0.006*) and dose (183.8±178.1yGym2 vs. 295.8±247.5yGym2, p&lt;0.013*). Procedure related mayor complications occurred in 1 patient from the DT group (acute stroke; 3%) and in no patients from the HPSD cohort. Early recurrence was reported from 4 patients treated with the DT catheter (12%) compared to 8 patients undergoing HPSD RFA (12 %) (p=1.000).

Conclusion

Temperature- and power- controlled AF ablation using 50 W was safe and effective. AI-guided HPSD ablation resulted in significantly shorter procedure times with significantly fewer RF applications for PVI, whereas total RF duration and fluoroscopy times were significantly higher in this cohort. Further studies are needed to confirm this initial observation.

The novel POLARx ablation system improves cryothermal single-shot guided pulmonary vein isolation: impact of individual pulmonary vein anatomy

Funding Acknowledgements

Type of funding sources: None.

Background

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). Recently, a novel balloon-guided cryothermal single shot device (POLARx) was introduced.

Purpose

This observational study aimed to evaluate ablation efficacy and outcome using the novel POLARx CB system compared to the established one and to access the impact of individual PV characteristics on freedom from arrhythmia recurrence in paroxysmal (PAF) and persistent (PERS) AF.

Methods

666 patients undergoing CB-guided ablation for AF were included. 601 patients treated with the AFA ablation system (Arctic Front Advance Pro, AFA) were compared to 65 consecutive patients who underwent PVI using the POLARx. Individual anatomical characteristics of the left atrium and PVs were assessed using pre-procedural cardiac magnetic resonance imaging (MRI). For each PV, the cross-sectional orifice area (CSOA) was determined. Follow-up examinations were scheduled after 3 and 6 months.

Results

Acute PVI was achieved in all patients (100%). 6-months AF-free survival was significantly higher in the POLARx cohort (POLARx: n=45, 69%; AFA: n=359, 60%; Log-rank p=0.037*). This applies to PAF (n=42, 65%, p=0.033*), PERS (n=23, 35%, p&lt;0.001*) and normal PV anatomy (2 left- and two right-sided PVs; n=57, 88%, p&lt; 0.001*). MRI found a comparable percentage of patients with normal PV anatomy (POLARx: n=57, 88%; AFA: n=512, 85%, p=0.126). A higher amount of variant PV anatomy was revealed in patients with PERS AF (p=0.043*), but this factor was not predictive for AF-recurrence (PAF: p=0.610; PERS: p=0.096). PAF patients with AF-recurrence presented with significantly larger CSOA of the left sided PVs and the right superior PVs (LSPV: 224.8 ± 98.1 mm2 vs. 220.6 ± 64.8 mm2, p&lt;0.001*; LIPV: 145.9 ± 63.2 mm2 vs. 140.4 ± 52.8 mm2, p&lt;0.001*; RSPV 268.9 ± 79.3 mm2 vs. 262.3 ± 75.6 mm2, p&lt;0.001*). In patients with PERS AF no association between CSOA and ablation outcome was observed. Multivariate Cox regression analyses identified the AFA ablation system (p=0.022*, hazard ratio (HR) 1.776, confidence interval (CI) 0.240-9.281) and PERS AF (p&lt;0.001*, HR 6.608, CI 0.220-73.839) as independent predictors for AF-recurrence.

Conclusion

PVI using the POLARx system improves freedom from AF recurrence independent of individual anatomical considerations and PV occlusion rates. For PAF patients, a significant association between CSOA and the outcome after CB- guided PVI was demonstrated.

News from the Cold Chamber: Clinical Experiences of POLARx versus Arctic Front Advance for Single-Shot Pulmonary Vein Isolation

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) represents a cornerstone in the treatment of atrial fibrillation (AF). Recently, a novel balloon-guided single shot device (POLARx, Boston Scientific) was designed. Our study aimed to compare the efficacy, safety and characteristics of the novel CB system with the established one (Arctic Front Advance (Pro), AFA, Medtronic). A total number of 596 patients undergoing CB-guided ablation for AF were included. 65 patients (65.0 ± 11.6, 31% female) undergoing PVI with the POLARx were compared to a cohort of 531 consecutive patients (63.0 ± 27.9, 25% female) treated with AFA. Acute PVI was achieved in all patients (n = 596, 100%). Total procedure duration (POLARx 113.3 ± 23.2 min, AFA 100.9 ± 21.3 min; p < 0.001) and fluoroscopy time (POLARx 10.5 ± 5.9 min, AFA 4.8 ± 3.6 min; p < 0.001) were significantly longer in the POLARx group. The POLARx balloon achieved significantly lower nadir temperatures (POLARx −57.7 ± 0.9 °C, AFA −45.1 ± 2.6 °C; p < 0.001) and a significantly higher percentage of pulmonary veins successfully isolated with the first freeze (p = 0.027 *). One major complication occurred in the POLARx (2%) and three (1%) in the AFA group. Both ablation systems are comparably safe and effective. AF ablation utilizing the POLARx system is associated with longer procedure and fluoroscopy times as well as lower nadir temperatures.

The Effect of Diabetes Mellitus on the Recurrence of Atrial Fibrillation after Ablation

Diabetes mellitus (DM) plays a crucial role in the regulation of atrial fibrillation (AF). This study aimed to evaluate the outcome of pulmonary vein isolation (PVI) using a single-shot device in patients with AF and DM. A total of 531 consecutive patients undergoing initial cryoballoon (CB)-guided PVI were evaluated. Two hundred eighty-one patients (53%) suffered from paroxysmal AF (PAF; mean age 51 ± 23.2 years, 26% female), 250 patients (48%) from persistent AF (PERS; 64 ± 10.0 years old, 30% female) and 80 patients (15%) were diagnosed with coincidental DM (68 ± 19.6 years old, 30% female). Follow-up visits were performed at 3, 6 and 12 months including 7-day Holter ECGs. Primary endpoint was the first documented recurrence of atrial tachyarrhythmia. AF recurrence occurred in 26% (140 patients). PAF patients with DM presented with a significantly higher risk for arrhythmia recurrence (Kaplan Meier analysis; Log rank p < 0.001 *). Multivariate analyses found DM to be an independent predictor (IP) for AF recurrence (p = 0.009 *, hazard ratio (HR) 4.363, confidence interval (CI) 1.456–13.074). In PERS, DM was associated with a 43% increase in AF recurrence (p = 0.320, HR 1.427, CI 0.707–2.879). DM has relevant effects on AF recurrence after PVI-only ablation approaches for AF. Major differences were observed in PAF as DM seems to favor the development of individual arrhythmia substrate, which is usually not yet present in PAF. In PERS, DM effects are less pronounced as individual fibrosis has already developed. Thus, personalized paths addressing individual arrhythmia substrates are needed in this specific cohort of patients.

Predictive value of diabetes mellitus for freedom from arrhythmia recurrence after cryoballoon-guided pulmonary vein isolation

Funding Acknowledgements

Type of funding sources: None.

Background

Diabetes mellitus (DM) has been identified to play an important role in the regulation of atrial fibrillation (AF). Data concerning the impact of DM on the development of individual arrhythmia substrates are still lacking.

Purpose

Therefore, the primary aim of this study was to examine the outcome of cryoballoon-guided pulmonary vein isolation (PVI) in patients (pts) suffering from DM and coexisting AF.

Methods

523 consecutive pts undergoing initial PVI using the 2nd generation cryoballoon were analysed. 273 pts (52%) suffered from paroxysmal AF (PAF) (51 ± 23.2 years old, 26% female), 250 pts (48%) from persistent AF (PERS) (63.9 ± 10.0 years old, 30% female) and 69 pts (13%) were diagnosed with DM (68 ± 19.6 years old, 30% female). Follow-up (FU) visits were performed at 3, 6 and 12 months including 7-day Holter ECGs. Primary endpoint was the first documented recurrence of any atrial arrhythmia after a 3 months blanking period (&gt; 30 sec.).

Results

Within the observation period of 12 months AF recurrence occurred in 29% (n = 151 pts). Regardless of the coincidence of DM, PAF pts were significantly younger than those with PERS (p = 0.001). PAF pts additionally suffering from DM presented with a significantly higher risk for arrhythmia recurrence (p = 0.047). Multivariate analyses verified DM as a strong independent predictor for arrhythmia recurrence associated with a &gt; 4 fold higher risk for recurrence after ablation (p = 0.009, hazard ratio (HR) 4.363, confidence interval (CI) 1.46-13.07). PERS pts showed a slightly increased rate of arrhythmia recurrence when additional DM was diagnosed. In these patients multivariate analyses revealed that DM was associated with a 43% higher risk for arrhythmia recurrence (p = 0.321, HR 1.143, CI 0.59-2.22). Beyond that, severe gender disparities were observed with female gender as independent predictor for arrhythmia recurrence (p = 0.027*, HR 1.927, CI 1.079-3.440).

Conclusions

DM has relevant implication for arrhythmia recurrence after PVI. More distinct effects were observed in PAF patients following AF ablation. This could be related to more severe arrhythmia substrates in PAF pts suffering from DM compared to PAF pts without additional DM and even more substantial structural changes in PERS. Thus, individual paths in ablation management are required in these pts with AF and coexisting DM.

Late diagnosed DiGeorge syndrome in a 44-year-old female: a rare cause for recurrent syncopes in adulthood-a case report

Background

DiGeorge syndrome, also known as ‘CATCH 22’, is the most common deletion in humans and is one of the velocardiofacial syndromes. It is characterized by a specific facial phenotype, and structural and functional abnormalities in the cardiac and endocrine systems. One form of endocrine system dysfunction is hypocalcaemia, which causes arrhythmic events and can result in a transient loss of consciousness. We present a case highlighting the late diagnosis of DiGeorge syndrome in a patient with recurrent episodes of syncope due to suspected arrhythmic events secondary to hypocalcaemia.

Case summary

A 44-year-old woman was referred for further investigation of recurrent syncope episodes and documented transient QT-prolongation with hypocalcaemia. Previous detailed cardiological examination, including invasive procedures such as coronary angiography and cardiac magnetic resonance tomography, was unremarkable. Slight characteristic facial dysmorphia and transient hypocalcaemia were strongly suggestive of DiGeorge syndrome. The diagnosis was confirmed by genetic testing. Calcium substitution was initiated and no recurrent episodes of syncope or arrhythmic events were reported during 12 months of follow-up.

Discussion

Clinical presentation and time of manifestation of the DiGeorge syndrome varies widely depending on the mutation expression extent. An atypical disease course may delay the diagnosis and appropriate management of affected patients. In this case, confirmation of the diagnosis allowed the initiation of appropriate treatment, reducing the risk for further events. Given that syncope and arrhythmia can be the first and only manifestation of late-onset DiGeorge syndrome, specialists in adult cardiology need to be aware of this presentation.