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.

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.

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.

Relationship among multifaceted factors including blood pressure at discharge and long-term clinical outcome in patients with cardiovascular diseases.

The relationship among blood pressure (BP) levels at discharge, other multifaceted factors assessed in cardiac rehabilitation programs, and prognosis for up to 2 years was examined in 154 consecutive cases (132 patients; 69 males; 79 ± 12 years, mean ± SD). A total of 72 composite events occurred (58 rehospitalizations from cardiovascular causes and 14 all-cause death events). The relationship between the systolic BP (SBP) at discharge and the long-term prognosis formed a J-shaped curve, with the event rate being lowest in patients with SBP of 115-125 mmHg. This relationship was still significant after adjustment of multifaceted factors assessed in cardiac rehabilitation programs.

Effects of intravenous nicorandil on the mid-term prognosis of patients with acute heart failure syndrome.

BACKGROUND: Acute heart failure syndrome (AHFS) remains a major clinical challenge because of its poor prognosis. Nicorandil, a hybrid compound of a potassium-channel opener and nitric oxide donor, has been reported to improve the prognosis of ischemic heart disease. We sought to evaluate the effect of intravenous nicorandil on the mid-term prognosis of AHFS. METHODS AND RESULTS: A total of 402 consecutive patients who were hospitalized for AHFS were divided into 2 groups according to the use of intravenous nicorandil: 78 patients in the Nicorandil group and 324 patients in the Control group. During the 180-day follow-up, death or rehospitalization for heart failure occurred in 7 patients in the Nicorandil group (9.0%) and in 75 patients (23.2%) in the Control group. Event-free survival rates were significantly higher in the Nicorandil group than in the Control group (P=0.006). Multivariate Cox hazard analysis revealed that age (hazard ratio (HR)=1.066, P<0.0001), systolic blood pressure (HR=0.983, P=0.0023), New York Heart Association class III/IV (HR=6.550, P<0.0001), log creatinine (HR=3.866, P=0.0106), and use of intravenous nicorandil (HR=0.179, P<0.0001) were significant predictive factors for the occurrence of death or rehospitalization for heart failure. CONCLUSIONS: Intravenous nicorandil treatment from the urgent phase of AHFS may improve the prognosis.

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.

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.

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.

Low diastolic blood pressure was one of the independent predictors of ischemia-like findings of electrocardiogram in patients who underwent coronary angiography.

BACKGROUND: The underlying cause of a high cardiovascular event rate in the population with low diastolic blood pressure (DBP) has not been fully elucidated. METHODS AND RESULTS: The relationship between DBP and ischemia-like findings on electrocardiography (ECG) was investigated in 187 patients who underwent coronary angiography. Patients with conditions affecting ECG (e.g. patients taking digitalis or those with old myocardial infarction, complete right bundle branch block, or hypokalemia) were excluded from the analyses. Ischemia-like ECG was defined as having one or more of the following: borderline Q wave [Minnesota code (MC) I 3], ST depression (MC IV 1-3), negative T wave (MC V 1-3), and complete left bundle branch block (MC VII 1). Based on this definition, 70 of 187 patients (37%) had ischemia-like ECG. Compared with the group without it, the group with ischemia-like ECG included more females (p<0.01), and had lower values of body mass index (p = 0.01), DBP (p<0.01), estimated glomerular filtration rate (p<0.01), left ventricular ejection fraction (LVEF; p<0.01), and higher values of age (p<0.01) and left ventricular mass index (LVMI; p<0.01). The severity of coronary artery disease did not differ between the groups. Receiver operating characteristics curve analysis revealed that 74.5 mmHg was the optimal cut-off point of DBP to predict ischemia-like ECG (area under curve, 0.63; 95% confidence interval, 0.55-0.71, p = 0.003). There were no significant relationships between systolic blood pressure and ischemia-like ECG. A multivariate analysis showed that female sex, low DBP (≤ 74.5 mmHg), LVMI, and LVEF were the significant factors for the ischemia-like ECG. The odds ratio of low DBP was 2.53 (95% confidence interval, 1.19-5.40; p = 0.02). CONCLUSIONS: Low DBP was one of the significant predictors of the ischemia-like ECG in the present study. Myocardial ischemia may be a part of the cause of high cardiovascular morbidity in the population with low DBP.