Atrial flutter catheter ablation in adult congenital heart diseases.

The important increase in life expectancy of adult patients with congenital heart disease (ACHD) has generated new challenges, including arrhythmias that represent one of the main late complications. Reentrant atrial arrhythmias are by far the main mechanism encountered, and catheter ablation has been now presented as a first-line therapy in this patient population. The number of procedures is expected to continuously increase year after year. The heterogeneity and complexity of phenotypes encountered require these cases to be performed by highly experienced operators, in specialized centers with multidisciplinary competencies. A thorough knowledge and understanding of anatomic specificities, vascular access issues, and main circuits encountered according to underlying phenotype is essential. Acute success rates have significantly improved and are now excellent, but recurrences remain a common issue, with different mechanisms or circuits frequently encountered. Observational data have suggested the interest of systematically targeting all inducible atrial arrhythmias, whether previously documented or not, and a lot of hope and research is based on the prediction of arrhythmia substrate before arrhythmia development by imaging or electroanatomic mapping to deliver a prophylactic patient tailored ablation approach. In this review, we summarize those different points in the most common or distinctive defects to offer a didactic overview of atrial flutter catheter ablation in ACHD patients.

Transbaffle/transconduit puncture using a simple CARTO-guided approach without echocardiography in patients with congenital heart disease.

INTRODUCTION: Catheter ablation (CA) of atrial tachyarrhythmias (ATs) in patients with complex congenital heart disease (CHD) often requires technically challenging transbaffle or transconduit puncture. The aim was to assess the feasibility and safety of transbaffle/transconduit puncture based on computed tomography (CT) three-dimensional (3D) reconstruction merged with electro-anatomical mapping (EAM) without per-procedure echocardiographic guidance. METHODS AND RESULTS: We included 18 consecutive CHD patients in two centers who had atrial-switch or Fontan surgery and underwent CA of AT by an antegrade approach requiring intracardiac puncture. Twelve patients with atrial-switch surgery and six patients with extracardiac Fontan surgery were referred for CA of AT. Cardiac CT with 3D reconstruction was performed before the procedure. The 3D volume of the systemic venous atrium or extracardiac conduit acquired by EAM was merged with the corresponding CT 3D reconstruction. The ablation catheter was positioned at the optimal puncture site. Under fluoroscopic guidance, the needle was positioned next to the ablation and the puncture was performed. Balloon expansion of the puncture site was performed in every case of transconduit puncture and in two (17%) cases of transbaffle puncture. Overall, 17 intra-atrial reentrant tachycarrythmias and 9 focal ATs were successfully ablated, with no acute complications. The median time to access the pulmonary atrium was 78.5 minutes (range, 55-185) and total median fluoroscopy time was 23 minutes (range, 7-53). CONCLUSIONS: Transbaffle and transconduit punctures can be performed safely in CHD patients by using a simple technique relying on CT 3D reconstruction and EAM.

Characteristics and clinical assessment of unexplained sudden cardiac arrest in the real-world setting: focus on idiopathic ventricular fibrillation.

Aims: Recent studies have shown that in more than half of apparently unexplained sudden cardiac arrests (SCA), a specific aetiology can be unmasked by a careful evaluation. The characteristics and the extent to which such cases undergo a systematic thorough investigation in real-life practice are unknown. Methods and results: Data were analysed from an ongoing study, collecting all cases of out-of-hospital cardiac arrest in Paris area. Investigations performed during the index hospitalization or planned after discharge were gathered to evaluate the completeness of assessment of unexplained SCA. Between 2011 and 2016, among the 18 622 out-of-hospital cardiac arrests, 717 survivors (at hospital discharge) fulfilled the definition of cardiac SCA. Of those, 88 (12.3%) remained unexplained after electrocardiogram, echocardiography, and coronary angiography. Cardiac magnetic resonance imaging yielded the diagnosis in 25 (3.5%) cases, other investigations accounted for 14 (2.4%) additional diagnoses, and 49 (6.8%) patients were labelled as idiopathic ventricular fibrillation (IVF) (48.7 ± 15 years, 69.4% male). Among those labelled IVF, only 8 (16.3%) cases benefited from a complete workup (including pharmacological testing). Younger patients [odds ratio (OR) 6.00, 95% confidence interval (CI) 1.80-22.26] and those admitted to university centres (OR 3.60, 95% CI 1.12-12.45) were more thoroughly investigated. Genetic testing and family screening were initiated in only 9 (18.4%) and 12 (24.5%) cases, respectively. Conclusion: Our findings suggest that complete investigations are carried out in a very low proportion of unexplained SCA. Standardized, systematic approaches need to be implemented to ensure that opportunities for specific therapies and preventive strategies (including relatives) are not missed.

Implantable cardioverter-defibrillator therapy among patients with non-ischaemic vs. ischaemic cardiomyopathy for primary prevention of sudden cardiac death.

Aim: The magnitude of benefit related to implantable cardioverter defibrillator (ICD) therapy for primary prevention of sudden cardiac death (SCD) in non-ischaemic cardiomyopathy (NICM) and ischaemic cardiomyopathy (ICM) has not been evaluated extensively in clinical practice. Methods and results: Of the 5539 consecutive patients enrolled in the multicentre Défibrillateur Automatique Implantable-Prévention Primaire (DAI-PP) study (2002-12), 5485 patients (with information on underlying heart disease) were included in the present analysis: 2181 (39.8%) had NICM and 3304 (60.2%) had ICM. ICM patients were older (63.7 ±10.3 vs. 60.6 ± 12.2 years, P < 0.0001), with a higher ejection fraction [27% (25-30) vs. 25% (20-30), P < 0.0001], narrower QRS (37.3% vs. 21.4% with QRS <120, P < 0.0001), and higher prevalence of sinus rhythm (77.3% vs. 74.0%, P = 0.009). During a mean follow-up of 3.1 ± 2.2 years, 814 patients died, giving a mortality incidence of 48.6 per 1000 person-years [95% confidence interval (CI) 45.2-51.9], higher among ICM patients (52.3, 95% CI 47.8-56.7) than in NICM patients (42.4, 95% CI 37.3-47.6; P = 0.008) (adjusted hazard ratio 1.31, 95% CI 1.06-1.61, P = 0.01). The increase in mortality among ICM patients was mainly due to non-cardiovascular mortality (P = 0.0002), whereas incidences of cardiovascular mortality (including ICD-unresponsive SCD) were similar in the two groups. Incidences of appropriate ICD interventions (anti-tachycardia pacing, shocks) were similar, but inappropriate therapies were more frequent in NICM (7.94 vs. 5.96%; P = 0.005). Conclusion: NICM and ICM patients had a same rate of ICD therapy for primary prevention of SCD in everyday practice. But, ICM patients more often died of a non- cardiovascular cause of death. Clinical Trial Registration: NCT 01992458.

Acute mitral isthmus block during catheter ablation with vein of Marshall ethanol infusion: Angiographic considerations.

BACKGROUND: Achieving bidirectional mitral isthmus block is still challenging. Conventional ablation methods involve radiofrequency applications on the endocardial aspect of the lateral mitral isthmus, and often epicardial applications inside the coronary sinus. AIM: To evaluate the impact of the systematic use of ethanol infusion in the vein of Marshall on the achievement of acute mitral isthmus block of additional epicardial component lesion. METHODS: We evaluated patients referred to two centres for long-standing persistent atrial fibrillation ablation or recurrent peri-mitral flutter. All patients had pulmonary vein isolation and mitral isthmus line using ethanol infusion in the vein of Marshall for the first procedure and additional radiofrequency ablation lesion if necessary. For redo procedures, additional ablations (atrial lines and complex fractionated atrial electrogram ablations, if needed) were also performed. RESULTS: We included 149 patients, and ethanol infusion in the vein of Marshall was not performed in 27 patients (18%). Among 122 patients, 115 had long-standing persistent atrial fibrillation (94.2%) and seven had peri-mitral flutter (5.8%). The mean duration of continuous atrial fibrillation was 53 months before ablation. Acute bidirectional mitral isthmus block was obtained in 115 (94.2%) of the 122 patients who received ethanol infusion in the vein of Marshall (77% when considering the total population). The mean radiofrequency delivery time to obtain mitral isthmus block was 2.6minutes for the endocardial mitral isthmus radiofrequency ablation and 2.6minutes for the epicardial mitral isthmus radiofrequency ablation. Failure to obtain mitral isthmus block was associated with increased mitral isthmus length and left atrial dilation. No major complications related to ethanol infusion in the vein of Marshall were observed. CONCLUSION: Ethanol infusion in the vein of Marshall, when feasible (82%), was a safe approach to obtaining a high success rate (94%) of acute bidirectional endocardial and epicardial mitral isthmus block.

Initiation and development of a percutaneous left atrial appendage closure programme: A French centre's experience and literature review.

BACKGROUND: Percutaneous left atrial appendage closure may be considered in selected patients with atrial fibrillation at significant risk of both thromboembolism and haemorrhage. AIMS: To report the experience of a tertiary French centre in percutaneous left atrial appendage closure and to discuss the outcomes compared with previously published series. METHODS: This was a retrospective observational cohort study of all patients referred for percutaneous left atrial appendage closure between 2014 and 2020. Patient characteristics, procedural management and outcomes were reported, and the incidence of thromboembolic and bleeding events during follow-up were compared with historical incidence rates. RESULTS: Overall, 207 patients had left atrial appendage closure (mean age 75.3±8.6 years; 68% men; CHA2DS2-VASc score 4.8±1.5 ; HAS-BLED score 3.3±1.1), with a 97.6% (n=202) success rate. Twenty (9.7%) patients had at least one significant periprocedural complication, including six (2.9%) tamponades and three (1.4%) thromboembolisms. Periprocedural complication rates decreased from earlier to more recent periods (from 13% before 2018 to 5.9% after; P=0.07). During a mean follow-up of 23.1±20.2 months, 11 thromboembolic events were observed (2.8% per patient-year), a 72% risk reduction compared with the estimated theoretical annual risk. Conversely, 21 (10%) patients experienced bleeding during follow-up, with almost half of the events occurring during the first 3 months. After the first 3 months, the risk of major bleeding was 4.0% per patient-year, a 31% risk reduction compared with the expected estimated risk. CONCLUSION: This real-world evaluation emphasizes the feasibility and benefit of left atrial appendage closure, but also illustrates the need for multidisciplinary expertise to initiate and develop this activity.

Atrial Fibrillation Ablation in a Patient with Cor Triatriatum Sinister and Left Common Pulmonary Vein: Impact of Left Atrium Anatomy on Ablation Approach.

Atrial fibrillation is the most common presentation in adult patients with cor triatriatum sinister. The key to successful and safe catheter ablation in these patients is an accurate exploration and thorough understanding of the left atrial anatomy, both before and during the procedure. Catheter manipulation is highly dependable on left atrial anatomy, including the interatrial septum, insertion of pulmonary veins and cor triatriatum membrane. Anatomical variants such as the left common pulmonary trunk may influence the ablation approach and outcome. We report the case of a 52-year-old patient with cor triatriatum sinister and the left common pulmonary vein variant who underwent successful high-power, short-duration catheter ablation for paroxysmal atrial fibrillation.

Catheter ablation in adults with congenital heart disease: A 15-year perspective from a tertiary centre.

BACKGROUND: With the growing adult congenital heart disease (ACHD) population, the number of catheter ablation procedures is expected to dramatically increase. Data reporting experience and evolution of catheter ablation in patients with ACHD, over a significant period of time, remain scarce. AIM: We aimed to describe temporal trends in volume and outcomes of catheter ablation in patients with ACHD. METHODS: This was a retrospective observational study including all consecutive patients with ACHD undergoing attempted catheter ablation in a large tertiary referral centre over a 15-year period. Acute procedural success rate and freedom from recurrence at 12 and 24 months were analysed. RESULTS: From November 2004 to November 2019, 302 catheter ablations were performed in 221 patients with ACHD (mean age 43.6±15.0 years; 58.9% male sex). The annual number of catheter ablations increased progressively from four to 60 cases per year (P<0.001). Intra-atrial reentrant tachycardia/focal atrial tachycardia was the most common arrhythmia (n=217, 71.9%). Over the study period, acute procedural success rate increased from 45.0% to 93.4% (P<0.001). Use of irrigated catheters (odds ratio [OR] 4.03, 95% confidence interval [CI] 1.86-8.55), a three-dimensional mapping system (OR 3.70, 95% CI 1.72-7.74), contact force catheters (OR 3.60, 95% CI 1.81-7.38) and high-density mapping (OR 3.69, 95% CI 1.82-8.14) were associated with acute procedural success. The rate of freedom from any recurrence at 12 months increased from 29.4% to 66.2% (P=0.001). Seven (2.3%) non-fatal complications occurred. CONCLUSIONS: The number of catheter ablation procedures in patients with ACHD has increased considerably over the past 15 years. Growing experience and advances in ablative technologies appear to be associated with a significant improvement in acute and mid-term outcomes.

A case report of ethanol infusion in the vein of Marshall using the right jugular vein approach.

BACKGROUND: Ethanol infusion has recently been described as a curative strategy for certain peri-mitral flutters by blocking electrical conduction across the mitral isthmus along with the Marshall bundle. The present case showed that a right jugular vein approach, less described, may be a good choice when performing an ethanol infusion in the vein of Marshall (VOM). CASE SUMMARY: A 45-year-old man was admitted to our unit for dyspnoea associated with an atypical atrial flutter with a cycle length of 320 ms. The left atrial activation map showed a peri-mitral counter-clockwise circuit. The atrial flutter cycle length went up to 345 ms once an endocardial and epicardial point-by point-ablation of the mitral line was completed. At this stage, a new activation map showed that the mitral line was still permeable with an epicardial conduction bridge through the VOM. We decided to use an ethanol infusion for the ablation of the VOM. The coronary sinus could not be thoroughly catheterized due to a winding and angular shape so we decided to try a right jugular vein approach. A total of 9 mL of ethanol was injected into the VOM. A final venogram showed the diffusion of ethanol around the VOM. Sinus rhythm was restored during the last ethanol infusion. A new voltage map confirmed the completion of the mitral line, and we confirmed the bidirectional block. DISCUSSION: The present case showed that a right jugular vein approach may be a good choice when catheterizing and performing an ethanol infusion in the VOM.

Catheter ablation of intra-atrial reentrant/focal atrial tachycardia in adult congenital heart disease: Value of final programmed atrial stimulation.

BACKGROUND: While outcomes of intra-atrial reentrant/focal atrial tachycardia (IART/FAT) catheter ablation have considerably improved in adult congenital heart disease (ACHD), recurrences remain common with different circuits frequently encountered. OBJECTIVE: We aimed to assess the value of programmed atrial stimulation after successful clinical IART/FAT catheter ablation in patients with ACHD. METHODS: This is a retrospective study including all patients with ACHD undergoing IART/FAT catheter ablation in a tertiary center. After successful catheter ablation of clinical arrhythmia, survival free from arrhythmia recurrence was analyzed according to whether all inducible IARTs/FATs were targeted. RESULTS: From 2004 to 2020, 238 IART/FAT catheter ablation procedures were performed (mean age 44.1 ± 15.0 years; 61.3% men). Acute procedural success of clinical arrhythmia was achieved in 208 procedures (87.4%). Among 122 procedures with programmed atrial stimulation (58.7%), at least 1 other IART/FAT was induced in 61 patients (50%). All inducible IARTs/FATs were ablated in 54 patients (88.5%), whereas 7 patients (11.5%) presented with at least 1 nontargeted inducible IART/FAT. Patients with nontargeted inducible IART/FAT had a higher risk of atrial arrhythmia episodes than did inducible patients treated with ablation of all IARTs/FATs (hazard ratio 5.7; 95% confidence interval 1.7-18.4; P = .004), with 12-month atrial arrhythmias recurrence rates of 22.9% and 77.7%, respectively. Inducible patients with successful ablation of all IARTs/FATs had a risk of recurrence similar to that of noninducible patients (hazard ratio 0.6; 95% confidence interval 0.3-1.3; P = .215). CONCLUSION: Beyond clinical IART/FAT catheter ablation in patients with ACHD, our findings suggest the interest of systematically targeting all remaining inducible arrhythmias, irrespective of whether previously documented.

Catheter ablation of electrical storm in patients with arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: Therapeutic strategies for electrical storm (ES) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) are not well defined. OBJECTIVE: The purpose of this study was to report the acute and long-term results of ventricular tachycardia (VT) radiofrequency catheter ablation (RFCA) as a treatment of ES in patients with ARVC. METHODS: This multicenter study retrospectively enrolled 23 consecutive patients with ARVC (mean age 43.6 ± 16.7 years; all men) who underwent 24 RFCA procedures for ES between 2003 and 2015. RESULTS: Thirteen patients (57%) had a previous VT RFCA procedure; 14 (61%) had right ventricular dysfunction and 7 (30%) left ventricular ejection fraction ≤ 50%. The clinical VT was inducible in 19 procedures (79%). Epicardial ablation was performed in 4 procedures (17%). The median number of targeted VTs was 1 (range 1-6). Complete acute success (no VT inducible) was achieved in 11 procedures (46%) and partial acute success (clinical VT nor inducible) in 11 (46%). After a median follow-up of 3.9 years (range 1 month-10 years), ES recurred in 2 patients and end-stage heart failure developed in 4 (17%), leading to 1 death and 3 heart transplantations. At 1-year follow-up, the probability of freedom from VT recurrence was 75% and did not significantly predict long-term survival. At the last evaluation, 8 patients (35%) were free of non-ß-blocker antiarrhythmic drugs as compared with 1 (4%) at baseline (P = .02). CONCLUSION: Catheter ablation was efficient to prevent ES recurrence in patients with ARVC. However, these patients were at high risk of evolution toward ARVC-related heart failure that was not associated with VT recurrence.

Radiotherapy in Patients With a Cardiac Implantable Electronic Device.

Recently, the Heart Rhythm Society published recommendations on management of patients with cardiac implantable electronic device (CIED) who require radiotherapy (RT). We aimed to report the experience of a teaching hospital, and discuss our practice in the context of recently published guidelines. We identified all consecutive CIED recipients (12,736 patients) who underwent RT between March 2006 and June 2017. Among them, 90 (1%) patients (78.2 ± 10 years, 73% male) had a CIED: 82 pacemakers and 8 implantable cardioverter-defibrillators. Two patients required CIED extraction prior to RT for ipsilateral breast cancer (no device replacement in 1 patient). Four patients (5%) were considered at high-risk, 35 (39%) at intermediate-risk, and the remaining 50 (56%) at low-risk for CIED dysfunction. Overall, only a minority of patients followed recommended local protocol during RT delivery (31%) and during follow-up (56%). CIED malfunction was detected in 5 patients (6%), mainly back-up mode resetting (80%), with 4 (including 3 pelvic cancer location) patients initially classified as being at intermediate-risk and 1 at low-risk. Four out of the 5 patients with CEID malfunction had received neutron producing beams. In conclusion, our findings underline the lack of rigorous monitoring of patients undergoing RT (though CIED malfunction appears to be rare and relatively benign in nature), and emphasize the interest of considering neutron producing beam for risk stratification as recommended in recent guidelines. Optimization of patient's management requires a close collaboration between both CIED clinicians and radiation oncologists, and more systematic remote CIED monitoring may be helpful.

Ablation of supraventricular arrhythmias in adult congenital heart disease: A contemporary review.

Supraventricular arrhythmias are an important and increasing cause of morbidity in adults with congenital heart disease, requiring specific management strategies. Pharmacological treatment has limited efficacy, and is often associated with some side-effects. Major improvements in catheter ablation techniques have opened new opportunities to better understand underlying mechanisms of supraventricular arrhythmias, offer better therapy, and eventually improve symptoms and quality of life in these patients. An array of tools and techniques are necessary to access relevant anatomical areas to address the arrhythmogenic substrate. The mechanism of these arrhythmias is mostly related to macroreentry around surgical scars or cavotricuspid isthmus-dependent flutter. The efficacy of catheter ablation is mainly dependent on the underlying congenital heart condition, with the most complex cases typically being associated with atrial switch and Fontan surgeries. Although relatively high rates of recurrence are seen after a single procedure, additional attempts are often helpful to decrease recurrences and improve symptoms. Catheter ablation in such patients continues to present many unique challenges that are best addressed by experienced multidisciplinary teams, at centres equipped with the proper catheters, imaging capabilities, mapping systems and support staff needed to maximize safety and success. Consensus indications have emerged that often support ablation as first-line therapy in these patients. In this comprehensive review, we aim to describe the specific issues associated with ablation of supraventricular arrhythmias in adult congenital heart disease, assess the results in contemporary practice and, finally, review the current indications.

Primary Prevention Implantable Cardioverter Defibrillator (ICD) Therapy in Women-Data From a Multicenter French Registry.

BACKGROUND: There are limited data describing sex specificities regarding implantable cardioverter defibrillators (ICDs) in the real-world European setting. METHODS AND RESULTS: Using a large multicenter cohort of consecutive patients referred for ICD implantation for primary prevention (2002-2012), in ischemic and nonischemic cardiomyopathy, we examined the sex differences in subjects' characteristics and outcomes. Of 5539 patients, only 837 (15.1%) were women and 53.8% received cardiac resynchronization therapy. Compared to men, women presented a significantly higher proportion of nonischemic cardiomyopathy (60.2% versus 36.2%, P<0.001), wider QRS complex width (QRS >120 ms: 74.6% versus 68.5%, P=0.003), higher New York Heart Association functional class (≥III in 54.2%♀ versus 47.8%♂, P=0.014), and lower prevalence of atrial fibrillation (18.7% versus 24.9%, P<0.001). During a 16 786 patient-years follow-up, overall, fewer appropriate therapies were observed in women (hazard ratio=0.59, 95% CI 0.45-0.76; P<0.001). By contrast, no sex-specific interaction was observed for inappropriate shocks (odds ratio ♀=0.84, 95% CI 0.50-1.39, P=0.492), early complications (odds ratio=1.00, 95% CI 0.75-1.32, P=0.992), and all-cause mortality (hazard ratio=0.87 95% CI 0.66-1.15, P=0.324). Analysis of sex-by- cardiac resynchronization therapy interaction shows than female cardiac resynchronization therapy recipients experienced fewer appropriate therapies than men (hazard ratio=0.62, 95% CI 0.50-0.77; P<0.001) and lower mortality (hazard ratio=0.68, 95% CI 0.47-0.97; P=0.034). CONCLUSIONS: In our real-life registry, women account for the minority of ICD recipients and presented with a different clinical profile. Whereas female cardiac resynchronization therapy recipients had a lower incidence of appropriate ICD therapies and all-cause death than their male counterparts, the observed rates of inappropriate shocks and early complications in all ICD recipients were comparable. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT01992458.

Implantable cardiac defibrillator among adults with transposition of the great arteries and atrial switch operation: case series and review of literature.

BACKGROUND: The experience with the implantable cardiac defibrillator (ICD) in patients with transposition of the great arteries (TGA) and history of atrial switch surgery remains limited. METHODS: Retrospective evaluation aiming to assess characteristics and outcomes of consecutive TGA patients with history of atrial switch surgery implanted with an ICD between January 2005 and June 2012 in four French centers. RESULTS: Of the 12 patients (median 34 years [28, 40]; 67% male), 4 patients (33%) were implanted for secondary prevention after symptomatic documented sustained ventricular tachycardia or sudden cardiac arrest. ICDs were implanted for primary prevention in 8 patients (67%), including cardiac resynchronization in 3 patients; severe systemic ventricle dysfunction was present in all cases (median ejection fraction 27% [20, 40]). Overall, one patient died during the ICD implantation secondary to refractory cardiac arrest after defibrillation testing. Over a median follow-up of 19 months [10, 106], 6 patients out of 11 (54%) experienced worsening of congestive heart failure, including 5 who were eventually transplanted. Overall, 3 patients (27%) experienced significant ICD-related complications, whereas only one patient (primary prevention indication) developed appropriate ICD therapy (successful anti-tachycardia pacing without shock). Half of the patients presented with at least one episode of sustained (≥ 5 min) atrial arrhythmia during follow-up. CONCLUSIONS: Our findings underline the key role of progressive heart failure in dictating outcomes among TGA patients with prior atrial switch repair. Our results also underline the need of better risk-stratification for sudden cardiac death in those patients.