Incidence of phrenic nerve injury during pulmonary vein isolation using different cryoballoons: data from a large prospective ablation registry.

AIMS: Phrenic nerve injury (PNI) is the most common complication during cryoballoon ablation. Currently, two cryoballoon systems are available, yet the difference is unclear. We sought to compare the acute procedural efficacy and safety of the two cryoballoons. METHODS: This prospective observational study consisted of 2,555 consecutive atrial fibrillation (AF) patients undergoing pulmonary vein isolation (PVI) using either conventional (Arctic Front Advance) (AFA-CB) or novel cryoballoons (POLARx) (POLARx-CB) at 19 centers between January 2022 and October 2023. RESULTS: Among 2,555 patients (68.8 ± 10.9 years, 1,740 men, paroxysmal AF[PAF] 1,670 patients), PVIs were performed by the AFA-CB and POLARx-CB in 1,358 and 1,197 patients, respectively. Touch-up ablation was required in 299(11.7%) patients. The touch-up rate was significantly lower for POLARx-CB than AFA-CB (9.5% vs. 13.6%, p = 0.002), especially for right inferior PVs (RIPVs). The touch-up rate was significantly lower for PAF than non-PAF (8.8% vs. 17.2%, P < 0.001) and was similar between the two cryoballoons in non-PAF patients. Right PNI occurred in 64(2.5%) patients and 22(0.9%) were symptomatic. It occurred during the right superior PV (RSPV) ablation in 39(1.5%) patients. The incidence was significantly higher for POLARx-CB than AFA-CB (3.8% vs. 1.3%, P < 0.001) as was the incidence of symptomatic PNI (1.7% vs. 0.1%, P < 0.001). The difference was significant during RSPV (2.5% vs. 0.7%, P < 0.001) but not RIPV ablation. The PNI recovered more quickly for the AFA-CB than POLARx-CB. CONCLUSIONS: Our study demonstrated a significantly higher incidence of right PNI and lower touch-up rate for the POLARx-CB than AFA-CB in the real-world clinical practice.

Validation of dual atrioventricular nodal physiology in dual atrioventricular nodal non-reentrant tachycardia via adenosine triphosphate injection during atrial pacing: A novel insight into the role of leftward inferior extension.

INTRODUCTION: Dual atrioventricular nodal non-reentrant tachycardia (DAVNNT) is a rare and challenging-to-diagnose arrhythmia, without previous reports associating it with a leftward inferior extension (LIE). METHODS: Diagnosis was made using adenosine triphosphate (ATP) injection during atrial pacing in a suspected DAVNNT patient. RESULTS: Ablation of the rightward inferior extension was unsuccessful in eliminating DAVNNT; however, subsequent ablation of the LIE successfully eradicated the arrhythmia. CONCLUSION: This unique case, marked by the first instance of DAVNNT caused by LIE, diagnosed through ATP injection, underscores the utility of this diagnostic approach and broadens the spectrum of our understanding and management of this condition.

Acute procedural efficacy and safety of a novel expandable diameter cryoballoon in atrial fibrillation ablation: Early results from a multicenter ablation registry.

INTRODUCTION: The major limitation of the current cryoballoon (CB) system is a fixed 28 mm balloon-size. We sought to analyze real-world early experience with novel-sized adjustable CB. METHODS: This multicenter observational study included 140 consecutive atrial fibrillation patients (71 years, 94 men, 86 paroxysmal) who underwent pulmonary vein (PV) isolation using expandable diameter CB capable of ablation at 28 or 31 mm. RESULTS: Out of 544 targeted PVs, 526 (96.7%) were successfully isolated by a size-adjustable CB with a 770 [690-870] second median application dose, while the remaining 18 required touch-up ablation. Among them, 326 (62.0%) PVs were isolated by a 31 mm balloon, and the rate was significantly higher for upper than lower PVs (73.0% vs. 45.7%, p < .0001) and highest for right superior (78.5%) and lowest for right inferior (39.9%) PVs. The biophysical parameters and time to isolation were comparable between the 28 and 31 mm balloons, however, the real-time PV potential monitoring capability was significantly higher for 31 mm than 28 mm balloons for the left superior PV. The esophageal temperature reached 15°C during left inferior PV ablation significantly more often with 31 mm than 28 mm balloons (43.1% vs. 18.2%, p = .008). Right phrenic nerve injury (PNI) occurred in 9 (6.4%) patients during applications (6 right superior, 2 right inferior PVs), and most occurred with a 31 mm balloon. CONCLUSIONS: Our real-world early data demonstrated high acute efficacy and safety of the novel-sized adjustable CB. The biophysical parameters were similar between the 28 and 31 mm balloons. No marked decrease in the incidence of PNI was observed even with 31 mm balloons.

Characteristics of two different cryoballoon systems for treatment of paroxysmal atrial fibrillation: study protocol for a multicenter randomized controlled trial (CONTRAST-CRYO Trial).

BACKGROUND: Single-shot pulmonary vein isolation (PVI) utilizing cryothermal energy is an effective and safe treatment for atrial fibrillation (AF) patients. A novel cryoballoon system, POLARx™, has been recently introduced. The aim of this study was to compare the efficacy, safety, and biophysical parameters of PVI between the novel cryoballoon system, POLARx™, and the standard cryoballoon system, Arctic Front Advance Pro™ (AFA-Pro), in patients with paroxysmal AF. METHODS: The CONTRAST-CRYO trial is a prospective, multicenter, open-label, randomized controlled study performed at seven large cardiac centers. This study was approved by the central ethics committee or the local ethics committee of each participating hospital and has been registered at UMIN Clinical Trials Registry (UMIN000049948). The trial will assign 200 patients with paroxysmal AF undergoing PVI to POLARx™ and AFA-Pro in a 1:1 randomization. The primary endpoint is the one-shot acute success rate of the right inferior pulmonary vein. Second endpoints include freedom from documented atrial fibrillation, atrial flutter, or atrial tachycardia without antiarrhythmic drugs at 12 months after the procedure, freedom from re-do procedures, the incidence of procedure-related adverse events, freezing duration, and the biophysical parameters during applications for each PV, total procedure and fluoroscopy time, and PVI durability during re-do procedures. CONCLUSION: The CONTRAST-CRYO trial is a prospective, multicenter, randomized study designed to elucidate the difference in the efficacy, safety, and biophysical parameters between POLARx™ and AFA-Pro in paroxysmal AF patients undergoing PVI. The findings from this trial may provide a valuable indication for selecting the optimal cryoballoon system. CLINICAL TRIAL REGISTRATION:  UMIN000049948.

Symptomatic periesophageal vagal nerve injury by different energy sources during atrial fibrillation ablation.

Background: Symptomatic gastric hypomotility (SGH) is a rare but major complication of atrial fibrillation (AF) ablation, but data on this are scarce. Objective: We compared the clinical course of SGH occurring with different energy sources. Methods: This multicenter study retrospectively collected the characteristics and clinical outcomes of patients with SGH after AF ablation. Results: The data of 93 patients (67.0 ± 11.2 years, 68 men, 52 paroxysmal AF) with SGH after AF ablation were collected from 23 cardiovascular centers. Left atrial (LA) ablation sets included pulmonary vein isolation (PVI) alone, a PVI plus a roof-line, and an LA posterior wall isolation in 42 (45.2%), 11 (11.8%), and 40 (43.0%) patients, respectively. LA ablation was performed by radiofrequency ablation, cryoballoon ablation, or both in 38 (40.8%), 38 (40.8%), and 17 (18.3%) patients, respectively. SGH diagnoses were confirmed at 2 (1-4) days post-procedure, and 28 (30.1%) patients required re-hospitalizations. Fasting was required in 81 (92.0%) patients for 4 (2.5-5) days; the total hospitalization duration was 11 [7-19.8] days. After conservative treatment, symptoms disappeared in 22.3% of patients at 1 month, 48.9% at 2 months, 57.6% at 3 months, 84.6% at 6 months, and 89.7% at 12 months, however, one patient required surgery after radiofrequency ablation. Symptoms persisted for >1-year post-procedure in 7 patients. The outcomes were similar regardless of the energy source and LA lesion set. Conclusions: The clinical course of SGH was similar regardless of the energy source. The diagnosis was often delayed, and most recovered within 6 months, yet could persist for over 1 year in 10%.

How to perform effective cryoballooon ablation of the left atrial roof: Considerations after experiencing more than 1000 cases.

INTRODUCTION: Cryoballoon ablation (CBA) of the left atrial (LA) roof in addition to a pulmonary vein isolation has been expected to improve the clinical outcomes post-atrial fibrillation (AF) ablation. We demonstrated the characteristics and efficacy of CBA of the LA roof through our experience with a large volume of procedures. METHODS: Among 1036 AF ablation procedures with CBA of the LA roof, 834 patients who underwent a de novo ablation were analyzed. RESULTS: Complete LA roof line conduction block was obtained in 767 patients (92.0%) solely by CBA (Group A). Compared with the other patients (Group B), the mean nadir balloon temperature during CBA of the LA roof (-44.5 ± 5.6°C for Group A vs. -40.5 ± 7.5°C for Group B, p < .01) and number of cryoballoon applications during the LA roof ablation with a circular mapping catheter located in the left superior pulmonary vein (1.3 ± 0.8 for Group A vs. 1.6 ± 1.0 for Group B, p = .02) were significantly lower in Group A. A multivariate analysis revealed that those were predictors of a complete LA roof conduction block after only CBA. The 1-year Kaplan-Meier atrial arrhythmia free rate estimates were 80.6% for Group A and 59.0% for Group B (p < .01). CONCLUSION: Complete LA roof line conduction block could be obtained with a cryoballoon without touch-up ablation in most cases. The LA roof CBA with a circular mapping catheter located in the right superior pulmonary vein was preferable to obtaining complete LA roof conduction block, which was important with regard to the clinical outcomes.

Retrograde fast pathway cryoablation inside the coronary sinus for slow-fast atrioventricular nodal reentrant tachycardia in a patient with persistent left superior vena cava.

INTRODUCTION: Persistent left superior vena cava (PLSVC) is accompanied by enlarged coronary sinus (CS) and deformation of the triangle of Koch. This makes anatomical evaluation of the atrioventricular (AV) nodal pathways difficult. METHODS: We attempted cryoablation of retrograde fast pathway located in the enlarged CS roof of PLSVC for slow-fast AV nodal reentrant tachycardia (AVNRT) induced by inadvertent antegrade fast pathway elimination during ablation of left atrial tachycardia. RESULTS: Slow-fast AVNRT was successfully eliminated without AV block progression. CONCLUSIONS: This is the first case of successful retrograde fast pathway ablation of the CS ostial roof for slow-fast AVNRT with PLSVC.

Laser Balloon Ablation in Patients with a Left Common Pulmonary Vein.

Pulmonary vein isolation (PVI) with a balloon-based visually guided laser ablation (VGLA) is regarded as a useful therapeutic tool for treating atrial fibrillation (AF). The clinical efficacy of a VGLA has never been fully investigated in patients with left common pulmonary vein (LCPV). We investigated the procedural safety as well as clinical usefulness of VGLA in patients with LCPV.This study consisted of 130 consecutive patients who underwent VGLA of de novo nonvalvular paroxysmal AF.Eleven patients (8.5%) had an LCPV (ostium maximal average diameter: 27.5 ± 4.9 mm, ostium minimal average diameter: 17.7 ± 3.5 mm). Nine out of 11 (81.8%) LCPVs were successfully occluded and isolated at the ostium with a VGLA-guided PVI. The ablation procedure time was significantly shorter in the patients with than without an LCPV (61.5 ± 15.4 versus 86.9 ± 32.9 minutes, P = 0.01). There was no difference regarding the atrial tachyarrhythmia recurrence between those with and without an LCPV (P = 0.18). A total of 15 patients underwent a redo procedure, but reconnections were not observed in any of the LCPV patients.The VGLA-guided PVI was a useful therapeutic tool even in patients with an LCPV. The presence of an LCPV might not be associated with an increased risk of any atrial tachyarrhythmia recurrence.

Predictors of Phrenic Nerve Injury During Pulmonary Vein Isolation for Curing Atrial Fibrillation With Balloon-Based Visually Guided Laser Ablation.

BACKGROUND: Pulmonary vein (PV) isolation (PVI) with balloon-based visually guided laser ablation (VGLA) is useful for treating atrial fibrillation (AF), but phrenic nerve injury (PNI) is an important complication. We investigated the predictors of developing PNI during VGLA.Methods and Results:We included 130 consecutive patients who underwent an initial VGLA of non-valvular paroxysmal AF. Twenty patients developed PNI during the PVI. The patients with PNI had a significantly larger right superior PV ostial area (RSPVOA) than the other patients (mean [±SD] 284.7±47.0 vs. 233.1±46.4 mm2, respectively; P<0.01). Receiver operating characteristic analyses revealed that the area under the RSPVOA curve was 0.79 (95% confidence interval [CI] 0.69-0.90) with an optimal cut-off point of 238.0 mm2(sensitivity, 0.58; specificity, 0.95). In multivariate analyses, a large RSPVOA (HR 1.02, 95% CI 1.01-1.03, P<0.01) and small balloon size (HR 0.70, 95% CI 0.50-0.99, P=0.04) were independent risk factors for PNI during VGLA. PNI remained in 13 patients after the procedure, but 12 of these patients recovered from the PNI during the follow-up period. CONCLUSIONS: The incidence of PNI during VGLA was relatively high, but PNI improved in most cases. A large RSPVOA and small balloon size were predictors of PNI during VGLA.

Long-Term Performance of Right Ventricular Implantable Cardioverter-Defibrillator Leads in Arrhythmogenic Right Ventricular Cardiomyopathy and Hypertrophic Cardiomyopathy.

Patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and hypertrophic cardiomyopathy (HCM) implanted with implantable cardioverter-defibrillators (ICDs) may show a large decrease in R-wave amplitude during long-term follow-up. However, it is unclear whether this decrease is higher in these patients than in those without structural heart disease. This study investigated ICD-lead intracardiac parameters over a long duration in patients with ARVC and HCM and compared these parameters with those of a control group. We included 50 patients (mean age, 55.2 ± 17.2 years; 26% female) with ICD leads in the right ventricular apex, and compared 7 ARVC and 14 HCM patients with 29 control patients without structural heart disease. ICD-lead parameters, including R-wave amplitude, pacing threshold, and impedance during follow-up, were compared. The difference in these parameters between the time of implantation and year 5 were also compared. There were no significant differences in R-wave amplitude at implantation among the 3 groups. The change in R-wave amplitude between the time of implantation and year 5 was significantly greater in the ARVC group (-3.3 ± 5.4 mV, P = 0.012) in comparison to the control group (1.3 ± 2.8 mV); the HCM group showed no significant difference (-0.4 ± 2.3 mV, P = 0.06). Thus, in the ARVC group, R-wave amplitude at year 5 was significantly lower than that in the control group (5.7 ± 4.8 mV versus 12.5 ± 4.5 mV, P = 0.001). In ARVC patients with ICDs, ventricular sensing is likely to deteriorate during long-term follow-up; however, in HCM patients, sensing may not deteriorate.

Aortic Plaque Distribution, and Association between Aortic Plaque and Atherosclerotic Risk Factors: An Aortic Angioscopy Study.

AIM: Knowledge of subclinical plaque morphology and plaque distribution in the aorta in vivo remains unclear. This study aimed to increase the body of knowledge in this area. METHODS: We enrolled 37 consecutive patients with stable angina pectoris patients who underwent non-obstructive angioscopy for both the coronary artery and aorta immediately after percutaneous coronary intervention. We evaluated the presence of aortic plaques and the distribution of plaque instability. Patients were allocated into two groups according to the number of vulnerable plaques in whole aorta (a low [0-11] and high [≥ 12] group). We evaluated the relationships between the two groups in terms of cardiovascular risk factors. RESULTS: Aortic plaques were identified using non-obstructive angioscopy in all patients, and the greatest number of plaques was found at the infrarenal abdominal aorta (IAA) (the aortic arch, the descending thoracic aorta, the suprarenal abdominal aorta, the IAA, and common iliac artery; 65%, 76%, 65%, 95%, and 49%, respectively; p＜0.001). The maximum yellow grade, and the number of intense yellow plaques, ruptured plaques, and thrombi were highest at the IAA (p＜0.001). The prevalence of diabetes mellitus and peripheral arterial disease was higher in the high vulnerable plaque group (83.3% vs. 40.0%, p=0.010, 50.0% vs. 8.0%, p=0.005, respectively). CONCLUSIONS: Aortic atherosclerosis was the most severe at the IAA, and aortic plaque vulnerability and distribution were associated with the prevalence of diabetes mellitus and peripheral artery disease in patients with stable angina pectoris. Non-obstructive angioscopy may identify patients at high risk of future aortic events.

Observation of an Asymptomatic Dissecting Aortic Aneurysm Using Non-Obstructive Angioscopy.

Non-obstructive angioscopy has become a novel method of evaluating atheromatous plaques of the aortic intimal wall. A 77-year-old man with coronary artery disease underwent percutaneous coronary intervention in the left descending artery. We subsequently used non-obstructive angioscopy to identify aortic atheromatous plaques and incidentally diagnosed an aortic dissecting aneurysm. Non-obstructive angioscopy demonstrated a great fissure in severe atheromatous plaques at the entry site of the aortic dissection identified by enhanced computed tomography. This is the first report to describe the aortic intimal findings of an aortic dissecting aneurysm in vivo by using trans-catheter angioscopy.

Intravascular Ultrasound and Angioscopy Assessment of Coronary Plaque Components in Chronic Totally Occluded Lesions.

BACKGROUND: The in vivo lesion morphologies and plaque components of coronary chronic total occlusion (CTO) lesions remain unclear.Methods and Results:We investigated 57 consecutive CTO lesions in 57 patients with stable angina pectoris undergoing elective percutaneous coronary intervention with intravascular ultrasound (IVUS) and coronary angioscopy (CAS) examination. All CTO lesions were classified according to the proximal angiographic lumen pattern; tapered-type (T-CTO) and abrupt-type (A-CTO). The differences in the intracoronary images of these lesion types were evaluated according to the location within the CTO segment. A total of 35 lesions (61.4%) were T-CTO. T-CTO lesions had higher frequencies of red thrombi (proximal 71.4%; middle 74.3%; distal 31.4%; P<0.001) and bright-yellow plaques (yellow-grade 2-3) (48.6%; 74.3%; 2.9%; P<0.001) at the proximal or middle than at the distal subsegment; A-CTO lesions showed no significant differences among the 3 sub-segments. At the middle subsegment, T-CTO lesions showed higher frequencies of positive remodeling (51.4% vs. 18.2%, P=0.01) and bright-yellow plaques (74.3% vs. 13.6%, P<0.001) compared with A-CTO lesions. Multivariate analysis identified bright-yellow plaque as an independent predictor (odds ratio, 7.25; 95% confidence interval, 1.25-42.04; P=0.03) of the occurrence of periprocedural myocardial necrosis. CONCLUSIONS: The combination of IVUS and CAS analysis may be useful for identifying lesion morphology and plaque components, which may help clarify the pathogenetic mechanism of CTO lesions.

Cardiac Magnetic Resonance Imaging of Very Late Intrapericardial Hematoma 8 Years after Coronary Artery Bypass Grafting.

A 55-year-old man presented with dyspnea, edema, and appetite loss. He had undergone coronary artery bypass grafting 8 years previously. He had jugular venous distention and Kussmaul's sign. Contrast-enhanced cardiac magnetic resonance imaging (CMRI) demonstrated an intrapericardial mass compressing the right ventricular (RV) cavity. T1- and T2-weighted black-blood images showed a mass with heterogeneous high signal intensity and a thick and dark rim. The mass was considered to be a chronic hematoma. After pericardiotomy with surgical removal of the hematoma, CMRI showed the marked improvement of the RV function. Late intrapericardial hematoma is rare and CMRI is useful for making a differential diagnosis.

A case of ventricular fibrillation as a consequence of capecitabine-induced secondary QT prolongation: A case report.

Capecitabine is an oral fluoropyrimidine which can prolong QT interval. However, there have been no reports that capecitabine induced ventricular fibrillation (VF) due to secondary QT prolongation in patients with no structural heart disease. A 39-year-old woman developed VF during the chemotherapy of capecitabine for colon cancer. At the administration, corrected QT interval (QTc) was prolonged to 559 ms despite no evidence of organic heart disease. Discontinuation of capecitabline normalized the QTc (414 ms). During the follow-up of eight years, neither the QTc prolongation nor the recurrent VF has been detected. We report the rare case of capecitabine-related VF without any organic heart disease. .

Assessment of the Safety and Efficacy of Edoxaban for the Treatment of Venous Thromboembolism Secondary to Active Malignancy.

Objective: To assess the safety and efficacy of edoxaban for the treatment of venous thromboembolism (VTE) secondary to active malignancy. Materials and Methods: We enrolled 48 patients with newly diagnosed VTE secondary to active malignancy that was treated with oral edoxaban for 1 year between September 2014 and August 2015. We retrospectively examined the presence or absence of recurrent symptomatic VTE, VTE-related mortality, and bleeding events. Results: No recurrent symptomatic VTE or VTE-related deaths were recorded, enabling efficient assessment. Treatment safety was determined based on the reports of bleeding. Bleeding was reported in two patients, with serious bleeding in one of them. Conclusion: Edoxaban is safe and effective for the treatment of VTE secondary to active malignancy.

Impact of optical coherence tomography- and coronary angioscopy-assessed neointimal tissue characteristics on occurrence of periprocedural myonecrosis in patients with in-stent restenosis.

Several characteristics of neointimal tissues, including neoatherosclerotic progression, have been reported in lesions with in-stent restenosis (ISR). However, the effects of these characteristics on outcomes after percutaneous coronary intervention (PCI) for ISR lesions remain unclear. We assessed the relationships between neointimal tissue characteristics and the occurrence of periprocedural myonecrosis (PMN) after PCI in ISR lesions. We investigated 72 ISR lesions in 72 patients with stable angina pectoris (SAP) who underwent pre- and post-revascularization optical coherence tomography (OCT) and coronary angioscopy (CAS). All lesions were classified as with PMN, defined by an elevated peak high-sensitivity cardiac troponin-T level during the 24-h post-PCI period, and without PMN. PMN was observed in 23 (31.9 %) lesions. PMN lesions had higher frequencies of OCT-derived thin-cap fibroatheroma (26.1 vs. 6.1 %, P = 0.03), CAS-derived intensive yellow neointima (30.4 vs. 10.2 %, P = 0.04), neointima with complex surface (60.9 vs. 28.6 %, P = 0.01), and CAS-derived atheromatous appearance (CAS-AAP), defined as yellow plaque including complex thrombi underneath disrupted neointimal coverage after ballooning (47.8 vs. 16.3 %, P = 0.008) at the most stenotic sites inside stents, compared to lesions without PMN. Multivariate logistic regression analysis identified CAS-AAP (odds ratio: 3.568, 95 % confidence interval: 1.109-11.475, P = 0.033) as an independent predictor of PMN. For ISR lesions in SAP patients, an OCT- and CAS-based assessment of neointimal tissue characteristics might help to predict the occurrence of PMN.