Clinical experience of idarucizumab use in cases of cardiac tamponade under uninterrupted anticoagulation of dabigatran during catheter ablation of atrial fibrillation.

Anticoagulants are prescribed for prevention of thromboembolic events (TE) of atrial fibrillation (AF), however, their effects have a negative impact on disastrous bleeding outcomes. Idarucizumab was developed to reverse the anticoagulation effects of dabigatran. This study aimed to retrospectively investigate the clinical efficacy and safety of idarucizumab in the setting of progressive emergent bleeding events associated with catheter ablation (CA). Dabigatran is given uninterruptedly as an anticoagulant in patients undergoing CA of AF. The capacity of idarucizumab to reverse the anticoagulant effects of dabigatran in patients with cardiac tamponade associated with CA was examined by measuring the activated partial thromboplastin time (aPTT), active clotting time (ACT), and prothrombin international normalizing ratio (PT-INR). The primary endpoint was effective hemostasis. This analysis included 21 patients receiving idarucizumab, given for restoration of hemostasis. In all 21 patients, hemostasis was restored at a median of 205.6 ± 14.8 min. Normal intraoperative cessation of bleeding was reported in 16 patients, and completion of hemostasis was also ascertained in the remaining four within 5 h. No TEs occurred within 72 h after the idarucizumab administration. Despite a significant reduction in the aPTT and ACT, no significant change was observed in PT-INR after administering idarucizumab. In emergency situations, idarucizumab was able to reverse dabigatran within a relatively short period without any serious adverse events.

Respiratory Collapse of the Inferior Vena Cava Reflects Volume Shift and Subsequent Fluid Refill in Acute Heart Failure Syndrome.

BACKGROUND: Fluid redistribution rather than fluid accumulation plays an important role in the development of acute heart failure (HF) syndrome. Patients with fluid redistribution develop acute HF without prominent volume overload. We investigated volume status by measuring the diameter of the inferior vena cava (IVC) and examining variations in hemoglobin and hematocrit. METHODS AND RESULTS: Seventy-four consecutive patients admitted for acute HF syndrome were analyzed. Blood tests and measurement of IVC diameter after stabilization of respiratory distress were performed on admission and were repeated after 24 h. IVC collapsibility index (IVC-CI) was calculated as (maximum IVC-minimum IVC)/maximum IVC. According to the initial IVC-CI, the patients were divided into the collapse group (IVC-CI ≥0.5: n=34) and the non-collapse group (IVC-CI <0.5: n=40). Initial blood pressure was higher in the collapse group (P<0.001). Although 24-h urine volume did not differ between the groups, hemoglobin (P<0.001) and hematocrit (P<0.001) decreased significantly in the collapse group but not in the non-collapse group after 24 h. Furthermore, IVC-CI significantly decreased in the collapse group after 24 h (P=0.003). CONCLUSIONS: In acute HF syndrome, IVC-CI ≥0.5 on admission suggests a volume shift from the central vein into the pulmonary vasculature. Fluid refill occurs within 24 h after admission. This observation could be helpful in selecting strategies for diuretic use. (Circ J 2016; 80: 1171-1177).

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%.

Outcomes and Safety of Very-Low-Dose Edoxaban in Frail Patients With Atrial Fibrillation in the ELDERCARE-AF Randomized Clinical Trial.

Importance: The prevalence of atrial fibrillation (AF) increases with age and is more common in frail patients. However, data are lacking on outcomes of oral anticoagulants (OACs) in very elderly patients with AF with frailty, who are ineligible for standard anticoagulant treatment. Objective: To compare very-low-dose edoxaban (15 mg daily) vs placebo across frailty status, including each of 5 frailty assessment parameters, among patients with AF involved in the ELDERCARE-AF (Edoxaban Low-Dose for Elder Care Atrial Fibrillation Patients) trial. Design, Setting, and Participants: This is a cohort study using data from ELDERCARE-AF, a multicenter, randomized, double-blind, placebo-controlled phase 3 study of Japanese patients with AF aged 80 years or older who were ineligible for OACs at doses approved for stroke prevention because of their high bleeding risks. Eligible patients were randomly assigned (1:1) to receive edoxaban or placebo. The study duration was from August 5, 2016, to November 5, 2019, with the last patient followed up on December 27, 2019. Data analysis was performed from February 2021 to February 2022. Exposure: Edoxaban (15 mg) once daily or placebo. Main Outcomes and Measures: The primary efficacy end point was the composite of stroke or systemic embolism, and the primary safety end point was major bleeding. Results: A total of 984 patients were randomly assigned to treatment (492 each to the edoxaban and placebo groups); 944 patients (402 frail patients [42.6%]; 542 nonfrail patients [57.4%]; mean [SD] age, 86.6 [4.3] years; 541 women [57.3%]) were included in this analysis. In the placebo group, the estimated event rates (SE) for stroke or systemic embolism were 7.1% (1.6%) per patient-year in the frail group and 6.1% (1.3%) per patient-year in the nonfrail group. Edoxaban was associated with lower event rates for stroke or systemic embolism with no interaction with frailty status or frailty assessment parameters. Major bleeding and major or clinically relevant nonmajor bleeding events were both numerically higher in the edoxaban group than in the placebo group, and no heterogeneity was observed with frailty status. Although both all-cause death and net clinical composite outcome occurred more frequently in the frail group than in the nonfrail group, there was no association with frailty status between the edoxaban and placebo groups. Conclusions and Relevance: Regardless of frailty status, among Japanese patients with AF aged 80 years or older who were ineligible for standard OACs, once-daily 15-mg edoxaban was associated with reduced incidence of stroke or systemic embolism and may be a suitable treatment option for these patients.

Transcatheter cryo-ablation of septal accessory pathways, multicenter observational study in Japan.

BACKGROUND: Ablation using radiofrequency energy has to be carefully performed when the arrhythmia substrate is located in close proximity to the atrioventricular (AV) node due to the risk of inadvertent permanent AV block. The aim of this study was to evaluate the efficacy and safety of catheter-based cryo-therapy for septal accessory pathways (APs). METHODS: A total of eleven patients (median = 56.3 years, range 13-74 years) with septal APs underwent cryoablation. Ice-mapping was performed during sinus rhythm and an AV reciprocating tachycardia utilizing the APs as a requisite limb with cooling of the catheter tip temperature to a maximum of -30℃ for less than 45 s. Cryo-ablation was performed for 4 min at a temperature of -80℃ only if ice-mapping abolished the pre-excitation or retrograde conduction over the AP without injury to the AV nodal conduction. RESULTS: Cryo-ablation was acutely successful in all eleven patients. No permanent cryo-related complications or adverse outcomes were reported. During the follow-up (range 14-26 months), no patients experienced any arrhythmia recurrences. CONCLUSION: Ice-mapping was a feasible and reliable method to determine the exact location of the APs owing to the possibility of validating the ablation site. Cryo-ablation of APs located near the AV junction is a safe and efficacious technique with a high success rate over the long term. IRB INFORMATION: Ethical Committee of Japan Red Cross Yokohama City Bay Hospital #2018-19.

Detection of diastolic potentials around the mitral annulus of structurally normal human hearts.

To examine the electrophysiologic characteristics of the subvalvular mitral region, we retrospectively searched for the presence of subvalvular diastolic potentials (DP) in 91 patients (mean age, 46.9 ± 16.6 years) who underwent catheter ablation of left-sided accessory pathways (AP). We detected low-amplitude (0.19 ± 0.09 mV) DP in 14 patients (15.4%), including 8 with overt preexcitation and 6 patients with concealed AP. The mean interval between ventricular electrogram and DP was 383 ± 46 ms (range, 306-475). DP were detected in 4 of 20 patients with antero-lateral, 3 of 38 with lateral, 4 of 12 with postero-lateral, 2 of 14 with posterior, and 3 of 10 patients with postero-septal AP. In 6 of 14 patients, DP were detected before ablation. In 4 of 8 patients with overt preexcitation, DP were consistently recorded after elimination of the delta wave, suggesting that they were not associated with AP conduction. In 6 of 11 patients, DP were observed during both sinus rhythm and ventricular pacing, suggesting that they were not artifacts. The electrophysiologic characteristics of clinically relevant DP around the mitral annulus suggest that, in normal human hearts, an anatomical substrate may be present around the mitral annulus.

Infective Endocarditis with No Underlying Disease for Which Bacterial Endophthalmitis Have Been the First Symptom.

Bacterial endophthalmitis is a rare complication of infective endocarditis (IE). We herein report a case of IE with no underlying disease for which endophthalmitis could have been the first symptom. A 58-year-old man was admitted to our hospital with a fever, vision disturbances, and pain in the left hand joint. His left eye was removed because fusion on the cornea progressed. Streptococcus agalactiae was detected in blood cultures, fluid cultures from his left hand joint, and the removed eye. Bacterial endophthalmitis may present as the first symptom of IE and develop without underlying disease due to S. agalactiae infection.

Discrimination between His-bundle and the right bundle branch during electrophysiologic studies.

BACKGROUND: The purpose of this study was to identify the His-bundle (HB) versus right bundle branch (RBB) during electrophysiologic studies, using the V3 phenomenon, and to compare the timing of HB versus RBB potentials of sinus cycles (His-ventricular [H-V] interval). METHODS: The study enrolled 16 patients without structural heart disease, who underwent electrophysiologic studies during which the H-V interval was within normal limits and the V3 phenomenon was induced during recordings of the HB and the RBB potentials by a multi-electrode catheter. The recording site of the earliest HB potential just before the V3 phenomenon was defined as the branching portion of His bundle (HBBP), the site immediately proximal to the HBBP as the HB, and the site immediately distal to the HBBP as the RBB. RESULTS: The HBBP was identified in all patients. In all cases but one patient, the H-V interval measured at the HB adjacent to the HBBP was > or =35 ms. However, in 12 patients, the H-V interval measured at the RBB adjacent to the HBBP was also > or =35 ms. CONCLUSIONS: The electrophysiologic identification of HB versus RBB by simultaneous recordings of HB and RBB potentials during induction of the V3 phenomenon was feasible. When the discrimination between HB and RBB was based on the measurement of the H-V interval, the proximal portion of the RBB was frequently misidentified as the HB.

Estimation of the left ventricular diastolic function with cardiac MDCT: correlation of the slope of the time-enhancement-curve with the mitral annulus diastolic velocity.

Patients with diastolic heart failure tend to have a poor outcome, similar to that for patients with systolic heart failure. The aim of this study was to explore the ability of MDCT to estimate the left ventricular diastolic function. Thirty patients with suspected coronary artery disease underwent MDCT and echocardiography. The early transmitral flow velocities (E) and the velocity of mitral annulus early diastolic motion (e') were measured in order to evaluate the diastolic function. The scanning delay of CT was determined using a test injection technique. The aortic enhancement was measured over the aortic-root lumen, and it was plotted over time to yield a time-enhancement-curve. A gamma variate function was then fit to the time-enhancement-curve and thereafter both the 'slope' of enhancement for each patient and the region of interest [ROI] were calculated. According to a univariate analysis, the slope of the time-enhancement-curve was found to correlate with the e' (r = 0.686, P = 0.000) and E/e' (r = -0.482, P = 0.007), however, no significant correlation was observed with the systolic parameters of the left ventricle. These results indicate that the slope of the time-enhancement-curve in the aorta significantly correlates with e', i.e. the diastolic parameters, which are independent of the systolic parameters. Based on these findings, we propose that the slope of the time-enhancement-curve may serve as a parameter for the left ventricular diastolic function on MDCT.

Typical atrial flutter with atypical flutter wave morphology due to abnormal interatrial conduction.

We report a case of typical counterclockwise atrial flutter (AFL) with conduction block from right to left atrium along the coronary sinus (CS) musculature, confirmed by discontinuous CS activation sequence during pacing near the ostium and differential right atrial pacing. AFL was associated with an atypical flutter wave morphology, due to the detour of the activation wavefront from right to left atrium via alternate interatrial electrical connections, such as Bachmann's bundle, the interatrial septum, or both.

Aborted cardiac arrest in a patient carrying KCNE1 D85N variant during the postpartum period.

The postpartum period is associated with an increased risk of fatal ventricular tachyarrhythmias in patients with congenital long QT syndrome (LQTS). We describe a 20-year-old female with LQTS who experienced aborted cardiac arrest during the postpartum period. Genetic screening identified a KCNE1 D85N variant, which has been reported to be a LQTS-causing gene variant, in the patient and her younger sister, whose QT interval was also prolonged. Since the allele frequency of this variant is almost 1%, it may be important to clarify whether such variant carriers indeed have an increased risk of fatal ventricular tachyarrhythmias during the postpartum period.

Increase in internal defibrillation threshold during acute myocardial infarction.

A 67-year-old man suffered an acute anteroseptal myocardial infarction complicated by multiple episodes of ventricular fibrillation, which were not systematically defibrillated by maximum, internal 35-J shocks delivered by an implanted cardioverter defibrillator (ICD). He had suffered from acute inferior myocardial infarction 6 years earlier, complicated with sustained polymorphic ventricular tachycardia (VT). Due to inducibility of sustained VT on an electrophysiologic study, an ICD was implanted. Defibrillation testing performed after healing of anteroseptal infarction was successful with a 10-J safety margin, suggesting that acute myocardial ischemia transiently elevated the internal defibrillation threshold.

Left-sided ICD implantation via right-sided venous access in a patient with left hemodialysis fistula.

A sufficient patency of the central vein ipsilateral to atriovenous fistula is the lifeline for hemodialysis patients. We describe a case with left dialysis fistula who underwent left-sided pectoral implantation of an implantable cardioverter defibrillator via right subclavicular venous access in order to avoid the possibility of development of left subclavian stenosis or occlusion and to achieve lower defibrillation thresholds. This approach may serve as an alternative choice in patients unsuitable for left-sided venous access and with higher defibrillation thresholds on right-positioned implantable cardioverter defibrillator.

Myocardial bundles with slow conduction properties are present on the left interventricular septal surface of normal human hearts.

INTRODUCTION: The aim of this study was to examine the electrophysiologic characteristics of the normal left interventricular septum (LIVS). METHODS AND RESULTS: We explored the LIVS in search of endocardial potentials following ventricular electrograms during sinus rhythm in 28 patients without structural heart disease. In all patients, low-frequency (mean amplitude: 0.81 +/- 0.33 mV) systolic potentials (LA1) were detected in a basal-to-apical activation sequence (earliest to latest QRS-LA1 interval: 93.3 +/- 10.8 ms to 127.1 +/- 16.6 ms). Programmed stimulation demonstrated decremental conduction properties, and the effective refractory period of the tissue between the ventricular electrogram and LA1 at baseline (376.7 +/- 48.8 ms) was significantly prolonged by disopyramide (421.3 +/- 54.1 ms, P < 0.05 vs baseline). In 21 patients (75%), diastolic potentials (LA2) morphologically similar to LA1 (mean amplitude: 0.52 +/- 0.17 mV) were detected in an apical-to-basal activation sequence (earliest to latest QRS-LA2 interval: 368.9 +/- 32.4 ms to 440.7 +/- 45.8 ms). Para-Hisian pacing with capture of the His bundle showed shorter S-LA1 and S-LA2 intervals compared to the beats without His-bundle capture but with ventricular capture (156.3 +/- 11.2 ms vs 183.2 +/- 12.3 ms, and 385.7 +/- 21.6 ms vs 397.4 +/- 23.4 ms, respectively, P < 0.0001). At the same rate, the LA1-LA2 interval was significantly shorter during right ventricular apical than atrial overdrive pacing (220.4 +/- 23.1 ms vs 261.4 +/- 30.7 ms, P < 0.0001). CONCLUSION: Unique myocardial bundles with slow conduction properties and various electrical connections with the specialized conduction system may exist in the LIVS of normal human hearts.

Coronary sinus recordings of double potentials associated with retrograde conduction through left atrioventricular accessory pathways.

INTRODUCTION: In some patients with left AV accessory pathway (AP), double potentials are recorded along the coronary sinus (CS) during retrograde AP conduction only. This electrophysiologic study was performed to clarify the origin and clinical significance of double potentials in 11 patients. METHODS AND RESULTS: The direction of activation of the first, relatively blunt component (DP1) was lateral to septal in 5 patients with anterior or anterolateral AP, centrifugal in 2 patients with posterior or posterolateral AP, and septal to lateral in 4 patients with posteroseptal AP, suggesting the earliest activation of DP1 was near the AP. The direction of activation of the second, sharper potentials (DP2) were septal to lateral in all patients. The double potentials were fused in the paraseptal CS region. Pacing from the lateral CS musculature or lateral left atrium reproduced the double potentials. The effective refractory period of the double potentials was reached by ventricular extrastimulation, and the left atrial deflection preceded the double potentials, excluding a ventricular or AP origin. CONCLUSION: In patients with connections between the paraseptal CS musculature and left atrium but no connections more laterally, retrograde left AP conduction is associated with double potentials in the CS recordings. The double potentials represent activation of the left atrial insertion of the AP (DP1) and later activation of the CS musculature (DP2) via connections between the paraseptal CS musculature and left atrium, respectively. The activation pattern of DP1 depends on AP location, thus providing important information for AP localization during CS mapping.

Electrophysiological characteristics and radiofrequency ablation of accessory pathways with slow conductive properties.

BACKGROUND: Atrioventricular accessory pathways (AP) with unusually long ventriculo-atrial (VA) conduction times are present in a significant subset of patients with the Wolff-Parkinson-White (WPW) syndrome, not including patients with the permanent form of atrioventricular junctional reciprocating tachycardia. METHODS AND RESULTS: We compared the electrophysiological characteristics and outcomes after radiofrequency (RF) ablation in 34 patients with the WPW syndrome, a VA interval >80 ms, and paroxysmal tachycardia with an RP/PR ratio <1 (the slow group), vs 80 patients with WPW syndrome and a VA interval <80 ms (the fast group). AP were found in the posteroseptal region significantly more often in the slow than in the fast group. In addition, the decremental conductive properties of the AP were more common in the slow than in the fast group. Catheter ablation of AP was highly successful in both groups, although ablation required a greater number of RF applications and longer procedure times in the slow group, especially for AP with decremental conductive properties. CONCLUSIONS: A posteroseptal AP location was more common in AP associated with long conduction times than in AP with typical conductive properties. Both types of AP were successfully ablated, although the slow group required longer procedures and more RF energy deliveries.