Bidirectional Association Among the Type of Atrial Fibrillation, Sleep-Disordered Breathing Severity, Heart Failure Progression, and Left Atrial Enlargement, in Patients with Atrial Fibrillation.

This study aimed to clarify (1) the association among the atrial fibrillation (AF) type, sleep-disordered breathing (SDB), heart failure (HF), and left atrial (LA) enlargement, (2) the independent predictors of LA enlargement, and (3) the effects of ablation on those conditions in patients with AF. The study's endpoint was LA enlargement (LA volume index [LAVI] ≥ 78 mL/m2).Of 423 patients with nonvalvular AF, 236 were enrolled. We evaluated the role of the clinical parameters such as the AF type, SDB severity, and HF in LA enlargement. Among them, 141 patients exhibiting a 3% oxygen desaturation index (ODI) of ≥ 10 events/hour underwent polysomnography to evaluate the SDB severity measured by the apnea-hypopnea index (AHI). The LA enlargement and HF were characterized by the LA diameter/LAVI, an increase in the B-type natriuretic peptide level, and a lower left ventricular ejection fraction.This study showed that non-paroxysmal AF (NPAF) rather than paroxysmal AF (PAF), the SDB severity, LA enlargement, and HF progression had bidirectional associations and exacerbated each other, which generated a vicious cycle that contributed to the LA enlargement. NPAF (OR = 4.55, P < 0.001), an AHI of ≥ 25.10 events/hour (OR = 1.55, P = 0.003), and a 3% ODI of ≥ 15.43 events/hour (OR = 1.52, P = 0.003) were independent predictors of an acceleration of the LA enlargement. AF ablation improved the HF and LA enlargement.To break this vicious cycle, AF ablation may be the basis for suppressing the LA enlargement and HF progression subsequently eliminating the substrates for AF and SDB in patients with AF.

Role of Sleep-Disordered Breathing and Epicardial Connections in the Recurrence of Atrial Fibrillation.

The presence of epicardial connections (ECs) between the pulmonary veins (PVs) and atrium may contribute to atrial fibrillation (AF) recurrence. This study aimed to determine the impact of sleep-disordered breathing (SDB) on the presence of ECs and the interplay between SDB and ECs on AF recurrence.We retrospectively reviewed 400 consecutive non-valvular AF patients. Among them, 235 patients exhibiting a 3% oxygen desaturation index (ODI) of ≥ 10 events/hour underwent polysomnography to evaluate the SDB severity, measured by the apnea-hypopnea index (AHI). To facilitate the ablation of AF and ECs, a high-density mapping catheter (HDMC) was employed. AF recurrence was evaluated over a 12-month period post-AF ablation.The key findings included: 1) 63% of AF patients with ECs had SDB with an AHI ≥ 20 events/hour. 2) Despite achieving complete PV isolations and precise EC ablation using an HDMC, SDB presence was associated with an increased AF recurrence. 3) Continuous positive airway pressure therapy for SDB improved AF recurrence among the AF patients with both ECs and SDB (57% versus 73%; P = 0.016). 4) AHI (odds ratio [OR] = 1.91, ≥ 28.4 events/hour) and left atrial volume (LAV) (OR = 1.42, ≥ 128.3 mL) were independent predictors of the presence of ECs, and AHI (OR = 1.44, ≥ 27.8 events/hour) was an independent predictor of the presence of AF recurrence.It is essential for physicians to recognise the potential complexity of ECs and SDB in AF patients. Thus, screening and treating SDB in AF patients presenting with ECs might play a pivotal role in suppressing AF recurrence.

Epicardial Connections After a Conventional Pulmonary Vein Antrum Isolation in Patients With Atrial Fibrillation.

BACKGROUND: The existence of epicardial connection(s) (ECs) between the pulmonary veins (PVs) and atrium may hinder establishing a complete PV antrum isolation (AI) (PVAI) in patients with atrial fibrillation (AF). Thus, the purpose of this study was to determine the prevalence and location of ECs inside the conventional PVAI lines.Methods and Results: Three-hundred consecutive patients with non-valvular AF were evaluated. This study revealed that: (1) the prevalence of patients with ECs and the number of ECs per patient between the PVs and atrium became significantly greater, respectively, in accordance with the progression of paroxysmal to long-lasting AF and left atrial enlargement; (2) some ECs were located at sites far distal to the PVAI lines; (3) 25% of ECs could be detected only by high-density mapping catheters, but not by conventional circular mapping catheters; (4) a B-type natriuretic peptide (BNP) level of 176.6pg/mL and left atrial volume (LAV) of 129.0 mL may be important predictors of the presence of ECs; and (5) the rate of conduction of ECs from the right PVs was dominantly to the atrium and His-bundle, and that from the left PVs to the coronary sinus was most dominant. CONCLUSIONS: The PVAI may not be completed by using only a conventional PVAI method, and additional EC ablation inside the PVAI lines detected using high-density mapping may be able to achieve a more complete PVAI.

Radiofrequency catheter ablation of premature ventricular contractions from the mitral annulus in patients without structural heart disease.

INTRODUCTION: We previously reported the clinical benefits of radiofrequency catheter ablation (RFCA) of premature ventricular contractions (PVCs) from the right ventricular outflow tract or near the His-bundle, which can often deteriorate the clinical status. PVCs from the mitral valve (MA-PVCs) also often deteriorate the patients' clinical status. This study aimed to evaluate the effect of ablating MA-PVCs with RFCA from a trans-interatrial septal approach on the clinical status in symptomatic patients with frequent MA-PVCs without structural heart disease. METHODS: The frequency of PVCs per the total heart beats by 24-hours Holter monitoring and New York Heart Association (NYHA) functional class in 22 patients with MA-PVCs were evaluated before and 6 months after RFCA. RESULTS: Procedural success was achieved in 20 (91%) of 22 patients. Of the 22 patients, in 15 (68%) and 1 (5%) patient, a successful RFCA on the left ventricular side of the MA using the trans-interatrial septal approach and trans-coronary sinus approach was achieved. Interestingly, in four (18%) patients, a successful RFCA on the left atrial (LA) side of the MA using a trans-interatrial septal approach was achieved. Ablating MA-PVCs readily improved the NYHA functional class compared to that before. A ≥0.62 peak deflection index and ≤30 years old may be one of the important predictors of successfully ablated MA-PVCs from the LA side of the MA. CONCLUSIONS: RFCA produces clinical benefits in patients with MA-PVCs. Further, it may be necessary to initially consider a trans-interatrial septal approach to ablate these PVCs.

Evaluation of coronary artery disease in patients with atrial fibrillation by cardiac computed tomography for catheter ablation: CADAF-CT trial.

Almost all institutions routinely perform cardiac computed tomography (CT) before radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) to evaluate the cardiac anatomy. The ideal timing of the CT image acquisition is different between for RFCA of AF and for evaluation of coronary artery lesions (CALs). Thus, the aim of this study was to assess whether 64- or 320-line routine cardiac CT scans before RFCA of AF could evaluate both coronary artery lesions and pulmonary veins (LA-PVs) anatomy at the timing of the image acquisition of the LA-PVs in patients with AF who underwent RFCA of AF. The CALs were evaluated in 606 consecutive patients who underwent RFCA of AF assessed by the ideal timing of the CT image acquisition for RFCA of AF, and myocardial ischemia (MI) was also evaluated in patients with severe coronary stenosis (≥ 50%) and unevaluable CALs due to their severe coronary calcification and banding artifact by additional examinations combined with exercise stress testing, 201Tl scintigraphy, and/or fractionated flow reserve measurements. This study revealed that, in patients with AF who underwent RFCA of AF, (1) both 64- and 320-line cardiac CT scans for RFCA of AF could evaluate CALs in 93% of those patients, (2) the prevalence of MI was 9%, (3) significant relationships between the CHADS2 score and prevalence of MI were observed (p = 0.003), and (4) the positive predict values of MI in patients with severe coronary stenosis (≥ 50%) and unevaluable CALs also significantly increased in accordance with the CHADS2 score (p = 0.003). The evaluation of CALs and MI by routine cardiac CT for RFCA of AF combined with the additional examinations may be one of the most feasible modalities for patients with AF.

Lipid-Lowering Therapy With Ezetimibe Decreases Spontaneous Atherothrombotic Occlusions in a Rabbit Model of Plaque Erosion: A Role of Serum Oxysterols.

OBJECTIVE: Plaque erosion is increasing its importance as one of the mechanisms of acute coronary syndromes in this statin era. However, the clinical efficacy of currently used lipid-lowering agents in the prevention of thrombotic complications associated with plaque erosion has not been clarified. Therefore, we examined the therapeutic effects of ezetimibe or rosuvastatin monotherapy on spontaneous atherothrombotic occlusion. APPROACH AND RESULTS: Femoral arteries of Japanese white rabbits, fed a high-cholesterol diet, were injured by balloon catheter, and then angiotensin II was continuously administrated. In 94% of these arteries, spontaneous thrombotic occlusions were observed after 5 weeks (median) of balloon injury. Histochemical analyses indicated that the injured arteries had similar pathological features to human plaque erosions; (1) spontaneous thrombotic occlusion, (2) lack of endothelial cells, and (3) tissue factor expression in vascular smooth muscle cells. Ezetimibe (1.0 mg/kg per day), but not rosuvastatin (0.6 mg/kg per day), significantly decreased thrombotic occlusion of arteries accompanied with accelerated re-endothelialization and the decreases of serum oxysterols despite the comparable on-treatment serum cholesterol levels. The 7-ketocholesterol inhibited the migration of human umbilical vein endothelial cells. Both 7-ketocholesterol and 27-hydroxycholesterol increased tissue factor expression in cultured rat vascular smooth muscle cells. Tissue factor expression was also induced by serum from vehicle- or rosuvastatin-treated rabbits, but the induction was attenuated with serum from ezetimibe-treated rabbits. CONCLUSIONS: We have established a novel rabbit model of spontaneous atherothromobotic occlusion without plaque rupture that is feasible to test the therapeutic effects of various pharmacotherapies. Ezetimibe may decrease atherothrombotic complications after superficial plaque erosion by reducing serum oxysterols.

Atrial Fibrillation in a Patient with Heparin-induced Thrombocytopenia Successfully Treated by Radiofrequency Catheter Ablation Using a Direct Thrombin Inhibitor.

A 74-year-old man was admitted to our hospital to undergo radiofrequency catheter ablation (RFCA) of persistent atrial fibrillation (AF). We found that he had a history of heparin-induced thrombocytopenia (HIT). Thus, a direct thrombin inhibitor, Argatroban Hydrate (Argatroban®), was used instead of heparin as anticoagulation therapy during the RFCA procedure. Finally, the AF was successfully treated by RFCA without any complications. Given these findings, the direct thrombin inhibitor Argatroban® may be effective and feasible for anticoagulation therapy during RFCA procedures for AF in patients with HIT, such as the present case.

Impact of Annual Cardiovascular Screening Tests in Patients with Type 2 Diabetes Mellitus without Previous Histories of Cardiovascular Disease: Four-year Clinical Outcomes.

Objective We previously reported that, among asymptomatic patients with type 2 diabetes mellitus (T2DM) without a history of cardiovascular disease (CVD), up to 19% of the patients with myocardial ischemia were detected by annual cardiovascular screening tests (ACVSTs). Thus, the present study assessed the long-term clinical outcomes of ACVSTs in those patients. Methods Six hundred and fifty-seven outpatients with T2DM who received ACVSTs at least once or not at all from April 2014 to March 2018 were defined as the S and NS groups, respectively. The data were compared between these two groups. Results This study revealed that, among outpatients with T2DM in our hospital over those four years, with the increasing frequency of receiving ACVSTs, 1) the frequency of the internal use of statins, anti-platelets, and renin-angiotensin system inhibitors, which are well-known as medications for preventing CVD, significantly increased; 2) low-density lipoprotein-cholesterol and triglyceride levels significantly improved; 3) levels of highly sensitive C-protein, a strong predictors of CVD, were significantly suppressed; 4) the progression of renal dysfunction was significantly suppressed; 5) the cumulative of four-point major adverse cardiovascular events and admissions due to heart failure significantly decreased; and 6) the cumulative of all-cause mortality was significantly suppressed. Conclusions Given the above, it may be important to continue ACVSTs in outpatients with T2DM without a history of CVD for several years.

Efficacy and Safety of Nepcell STM in Achieving Hemostasis After Removal of a 15-Fr Femoral Venous Sheath in Patients Undergoing Cryoballoon Ablation for Atrial Fibrillation.

Background: Hemostasis at the femoral venous access site after cryoballoon ablation (CA) for atrial fibrillation (AF) is often prolonged because of aggressive anticoagulation and the use of 15-Fr-caliber sheaths. The Nepcell STM (NC) is a newly developed hemostatic pad made of fibrosed calcium alginate extracted from natural seaweed. The calcium ions from the NC accelerate the clotting cascade. This single-center randomized clinical trial assessed the efficacy and safety of the NC in patients undergoing CA for AF. Methods and Results: In all, 62 patients undergoing CA for non-valvular paroxysmal AF were randomly assigned to either the NC or control group. The primary endpoints of this study were time to hemostasis, internal hemorrhage, and rebleeding. Secondary endpoints were the length of hospital stay (LOS) and vascular complications at 1 month. The time to hemostasis was significantly shorter in NC than control group (mean [±SD] 377±216 vs. 505±241 s; P=0.031). The frequency of internal hemorrhaging (6% vs. 37%; P=0.003) and rebleeding (0% vs. 13%; P=0.033) was lower in the NC than control group, contributing to a decreased LOS in the NC group (3.56±0.67 vs. 4.23±0.73 days; P<0.001). There were no NC-related vascular complications at the 1-month echographic examination. Conclusions: The use of NC was associated with a shorter hemostasis time and fewer bleeding complications in patients undergoing CA for AF, leading to a shorter LOS.

Influence of Serum Cholinesterase Levels on Patients Suspected of Having Stable Coronary Artery Disease.

Objective The serum cholinesterase (ChE) level has been used for the evaluation of the nutritional status in daily practice. It has been reported that the serum ChE level is significantly more elevated in patients with three-vessel coronary disease than in normal subjects. Thus, the aim of this study was to assess the influence of serum ChE levels in patients suspected of having stable coronary artery disease (CAD). Methods The relationship between myocardial ischemia and the serum ChE levels was evaluated in 559 consecutive patients suspected of having stable CAD without a history of cardiovascular disease admitted to our hospitals to undergo coronary angiography. Results This study revealed that, in patients suspected of having stable CAD, 1) the frequency of myocardial ischemia was significantly increased in accordance with the serum ChE levels (p<0.001); 2) higher ChE levels were associated with a higher body mass index (p<0.001) and the co-existence of dyslipidemia (p<0.001), including higher values of low-density lipoprotein-cholesterol (p<0.001) and triglycerides (p<0.001) and serum albumin (p<0.001), as well as a younger age (p<0.001); 3) the specificity and sensitivity of myocardial ischemia were 0.599 and 0.658 at the ChE level of 286 IU/L, respectively; and 4) an increased serum ChE (OR=1.66, p<0.001) was an independent risk factor for myocardial ischemia, in patients suspected of having stable CAD. Conclusion The serum ChE level may be an important diagnostic biomarker in patients suspected of having stable CAD.

Importance of the length of the myocardial sleeve in the superior vena cava in patients with atrial fibrillation.

BACKGROUND: Pulmonary vein (PV) antrum isolation (PVAI) has proven to be a useful strategy for radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) worldwide. However, non-PV foci, especially from the superior vena cava (SVC), play an important role in initiating and maintaining AF. METHODS: In all, 427 consecutive patients with non-valvular AF who were admitted to our hospitals to undergo RFCA of AF using an EnSite™ system were evaluated. The length from the top of the sinus node to the top of the myocardial sleeve of SVC (L-SVC), longer and shorter diameter of SVC of 1 cm above of junction of right atrium and SVC, and local activation time (LAT) of SVC were measured. Then, the SVC firing was evaluated by an intravenous administration of isoproterenol and adenosine triphosphate. RESULTS: L-SVC, longer and shorter diameter of SVC, and LAT of SVC were significantly longer in the SVC firing group than non-SVC firing group (P < .05). Moreover, in accordance with the L-SVC, the frequency of the SVC firing significantly increased (P < .001). A univariate analysis and multivariate statistical analysis revealed that L-SVC longer than 37.0 mm (odds ratio 6.39) and longer diameter of SVC (odds ratio 6.78) were independent risk factors for SVC firing in patients with AF who underwent RFCA of AF. CONCLUSIONS: In view of these findings, L-SVC longer than 37.0 mm longer diameter SVC longer than 17.0 mm may be one of the important predictors of SVC firing in patients with AF.

A Case of a Figure of Eight Atrial Tachycardia after a Pulmonary Vein Antrum Isolation of Atrial Fibrillation.

A 66-year-old female, whom received a pulmonary vein (PV) isolation (PVAI) with linear ablation of the carina lines between the superior and inferior PVs of both the right and left PVs for atrial fibrillation (AF), was admitted to receive a radiofrequency catheter ablation (RFCA) of symptomatic drug-refractory atrial tachycardia (AT). The EnSiteTM analysis by the AdvisorTM HD Grid catheter during the AT could easily detect that the carina between the right superior and inferior PVs exhibited a low voltage area (< 0.5 mV), in addition to the fact that the electrical activation turned around the right PVs in a figure 8, even though mapping was performed during AT. This AT was steadily terminated, after commencing the radiofrequency energy delivery to the carina of the right PVs.

Evaluation of Coronary Artery Disease in Patients with Atrial Fibrillation by Cardiac Computed Tomography for Catheter Ablation: CADAF-CT Trial 2.

Objective We recently reported that routine cardiac computed tomography (CT) scans for radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) could steadily detect coronary artery lesions (CALs) and could accurately detect myocardial ischemia in 9% of patients with AF who underwent RFCA of AF. The aim of this study was to identify the independent risk factor (s) of myocardial ischemia in those patients. Methods Patient characteristics, blood test, CALs, Ordinal coronary calcium scoring (OCCS), and myocardial Ischemia (MI) were evaluated in 757 consecutive patients who underwent RFCA of AF. Results There were 685 and 72 patients without and with myocardial ischemia, respectively. A univariate analysis and multivariate statistical analysis revealed that a male gender (Odds ratio 2.11), a high number of co-existing coronary risk factors (NCCRF ≥3) (Odds ratio 2.03), an elevated brain natriuretic peptide level (BNP ≥100 pg/mL) (Odds ratio 3.37), an enlarged left atrial volume (≥90 mL) (Odds ratio 2.91), and a high OCCS (≥4) (Odds ratio 13.0) were independent risk factors of myocardial ischemia in patients undergoing RFCA of AF. Conclusion The high OCCS (≥4) by cardiac CT was the strongest independent risk factor of myocardial ischemia in those patients. However, physicians may be able to find the high risk patients of myocardial ischemia by evaluating a male gender, in the presence of a high NCCRF (≥3) and elevated BNP (≥100 pg/mL) without OCCS by cardiac CT in patients undergoing RFCA of AF.

Radiofrequency catheter ablation of premature ventricular contractions from near the His-bundle.

OBJECTIVE: This study aimed to investigate the effects of radiofrequency catheter ablation (RFCA) and clinical and electrophysiological characteristics in symptomatic patients with premature ventricular contractions (PVCs) from near the His-bundle (His-PVCs). METHODS: The patient characteristics, prevalence of complications with any life style related disease (ALSRD) including hypertension, dyslipidemia, or diabetes mellitus, and/or cardiovascular disease (CVD) including coronary artery disease, cerebrovascular disease, renal dysfunction, or cardiomyopathy, clinical status, frequency of PVCs evaluated by 24hour Holter monitoring, echocardiography including the left ventricular diastolic dysfunction (LVDD) parameters, and electrophysiological findings were evaluated in 14 consecutive symptomatic patients with His-PVCs. RESULTS: The prevalence of males, being elderly and/or slightly obese, current and/or history of smoking, ALSRD or CVD related complications, and LVDD probably resulting from ALSRD and/or CVD complications were higher in patients with His-PVCs. RFCA of His-PVCs steadily decreased the PVC frequency and improved the systolic function, LV dilation, and clinical status, but not the LVDD. There was a significant relationship between the accordance rate of the QRS polarity between sinus rhythm and His-PVCs and the distance between the successful ablation site and His-bundle. CONCLUSION: The analysis of the QRS duration and accordance rate of the QRS polarity between sinus rhythm and His-PVCs before the RFCA may help to determine the distance between the origin of the PVCs and His-bundle. Further, the appropriate ablation catheter may be selected during the RFCA procedure. Finally, RFCA may be one of the most effective, feasible, and safest therapies for symptomatic patients with His-PVCs.

A case of paroxysmal atrial fibrillation in a patient successfully treated by radiofrequency catheter ablation with a severely right-sided dislocation of the heart after a total right lung excision.

A 72-year-old woman with symptomatic and drug-refractory paroxysmal atrial fibrillation (AF) underwent radiofrequency catheter ablation (RFCA). She had a history of a total right lung excision. Her chest X-ray and computed tomography (CT) revealed a severely sight-sided dislocation of the heart. Thus, the procedure was carefully performed under guidance of a CT, intracardiac echogram, atriography, and 3D mapping system. Finally, the AF was successfully treated by RFCA without any complications.

Paroxysmal Atrial Fibrillation in Patients Successfully Treated by Radiofrequency Catheter Ablation with Severely Compression, Lateral Displacement, and Clockwise Rotation of Their Hearts due to Severe Pectus Excavatum.

Two cases with severe pectus excavatum and symptomatic atrial fibrillation (AF) underwent radiofrequency catheter ablation (RFCA). Their chest X-ray and computed tomography (CT) findings revealed lateral displacement and clockwise rotation of their hearts, and severe right atrial and mild right ventricular compression against the sternum, but no left atrium compression against the spinal column. The procedure was therefore carefully performed under guidance with CT, intra-cardiac echography, atriography, and a three-dimensions mapping system. Finally, the AF was successfully treated by RFCA without any complications. These findings underscore the importance of understanding cases of abnormal anatomy and carefully designing a strategy before performing any procedure.

A case of premature ventricular complexes/ventricular tachycardia from the left ventricular outflow tract successfully ablated from the distal great cardiac vein.

We experienced a 41-year-old male with premature ventricular complexes/ventricular tachycardia from the left coronary cusp and distal great cardiac vein of the left ventricular outflow tract successfully treated by radiofrequency catheter ablation utilizing a 3D mapping system (EnSiteNavX/Velocity™ Cardiac Mapping System, St. Jude Medical, St. Paul, MN, USA) without any complications. .