Search

Background: This study aimed to establish a systematic method for diagnosing atrioventricular nodal reentrant tachycardia (AVNRT) with a bystander concealed nodoventricular pathway (cNVP). Methods: We analyzed 13 cases of AVNRT with a bystander cNVP, 11 connected to the slow pathway (cNVP‐SP) and two to the fast pathway (cNVP‐FP), along with two cases of cNVP‐related orthodromic reciprocating tachycardia (ORT). Results: The diagnostic process was summarized in three steps. Step 1 was identification of the presence of an accessory pathway by resetting the tachycardia with delay (n = 9) and termination without atrial capture (n = 4) immediately after delivery of a His‐refractory premature ventricular contraction (PVC). Step 2 was exclusion of ORT by atrio‐His block during the tachycardia (n = 4), disappearance of the reset phenomenon after the early PVC (n = 7), or dissociation of His from the tachycardia during ventricular overdrive pacing (n = 1). Moreover, tachycardia reset/termination without the atrial capture (n = 2/2) 1 cycle after the His‐refractory PVC was specifically diagnostic. Exceptionally, the disappearance of the reset phenomenon was also observed in the two cNVP‐ORTs. Step 3 was verification of the AVN as the cNVP insertion site, evidenced by an atrial reset/block preceding the His reset/block in fast–slow AVNRT with a cNVP‐SP and slow–fast AVNRT with a cNVP‐FP or His reset preceding the atrial reset in slow–fast AVNRT with a cNVP‐SP. Conclusion: AVNRT with a bystander cNVP can be diagnosed in the three steps with few exceptions. Notably, tachycardia reset/termination without atrial capture one cycle after delivery of a His‐refractory PVC is specifically diagnostic. [ABSTRACT FROM AUTHOR]

A novel Diamond Temp™ (DT; Medtronic, Minneapolis, MN, USA) catheter has enabled performing a surface temperature-controlled ablation. The chemical vapor deposition diamond of the ablation catheter acts as a thermal radiator and is useful for effective cooling of the ablation catheter tip. However, a detailed analysis of the lesion formation with this catheter remains unknown. DT catheters were used in an excised swine heart experimental model. A cross-sectional analysis of 60-s lesions [a combination of various energy power settings (30, 40, and 50 W), and various contact forces (CF) (10, 30, and 50 g)] and a longitudinal analysis [a combination of various powers (40 W or 50 W), various CFs (10, 30, and 50 g), and various ablation times (5 s, 10 s, 15 s, 20 s, 25 s, 30 s, and 60 s)] of the DT catheter were analyzed. The maximum lesion depth, maximum diameter, and lesion volume with a 10 g ablation were significantly lower than those with a 30 g or 50 g ablation. There were no significant differences in the lesion formation between the 30 g ablation and 50 g ablation under each radiofrequency (RF) power setting. The impedance drops with steam pops were significantly greater than those without steam pops (pop (+) vs. pop (−), 26.2 ± 6.6 Ohm vs. 18.4 ± 7.1 Ohm, p = 0.0001). A non-linear, time-dependent increase in the lesion depth and diameter was observed for all power and CF settings. Comparing the lesion depth and diameter between 40 W and 50 W under the same CF setting and same ablation time, most of the settings had no significant difference. Ablation lesions created with the DT catheter were similar to other catheters. Similar ablation lesions were created with the 40 W or 50 W ablation under the same CF setting and same ablation time. Regardless of the ablation power, monitoring the general impedance during the RF application was indispensable for a safe procedure. [Display omitted] • The research of radiofrequency catheter ablation by ex vivo experimental model • Wattage feedback and incidence during stem pops with diamond tip catheter • Effect of the chemical vapor deposition diamond of the catheter tip • A detail analysis of the lesion formation with diamond tip catheter [ABSTRACT FROM AUTHOR]

The mechanical properties of the myocardium in the left ventricle and right atrium were estimated by simultaneously measuring the local impedance (LI) and contact force (CF) using an ablation catheter. Radiofrequency catheter ablation (RFCA) is a well-established arrhythmia treatment. Monitoring the RF power, CF and properties of myocardium during RFCA are necessary to estimate the effect of ablation. Indices, such as CF, lesion size index and ablation index, do not include the myocardium mechanical properties. Therefore, there is the risk of side effects, such as cardiac tamponade, by excessive catheter indentation into vulnerable areas. We propose the simultaneous measurement of LI and CF for estimating the myocardial mechanical properties to reduce the side effects. In this study, an in vitro experimental system was constructed to measure LI and CF via the catheter. The relationship between the porcine myocardial tissue thickness and CF–LI curve was investigated using the left ventricle and right atrium. Power function coefficients approximating the CF–LI curve increased with thicker left ventricle. The thickness of the myocardium can be estimated by simultaneously measuring LI and CF. Intraoperative measurement of the myocardial mechanical properties can be used to determine the ablation conditions at each site. [ABSTRACT FROM AUTHOR]

Introduction: Local impedance (LI) parameters of IntellaNav STABLEPOINT for successful pulmonary vein isolation (PVI) of atrial fibrillation (AF) remain unclear. The purpose of this study was to seek LI data achieving successful PVI. Methods: Consecutive AF patients who underwent catheter ablation with STABLEPOINT were prospectively enrolled in two centers. PVI was performed under a constant 35‐or 40‐watt power, 20‐s duration, and >5‐g contact force. The operators were blinded to the LI data. The characteristics of all ablation points with/without conduction gaps (Unsuccess or Success tags) after the first‐attempt PVI were evaluated for the right/left PVs and anterior/posterior wall (RPV/LPV and AW/PW, respectively), and cutoff values of LI data were calculated for successful lesion formation. Results: A total of 5257 ablation points in 102 patients (65 [58–72] years old, 65.7% male) were evaluated. The LI drop values were higher in the Success tags than Unsuccess tags on the LPV‐AW and RPV‐AW/PW (p <.001), except for the LPV‐PW (p =.105). The %LI drop values (LI drop/initial LI) were higher for the Success tags in all areas (15.8 [12.2%–19.6%] vs. 11.6 [9.7%–15.6%] in LPV‐AW: p <.001, 15.0 [11.5%–19.3%] vs. 11.4 [8.7%–17.3%] in LPV‐PW: p =.035, 15.3 [11.5%–19.4%] vs. 9.9 [8.1%–13.7%] in RPV‐AW: p <.001, and 13.3 [10.1%–17.4%] vs. 8.1 [6.3%–9.5%] in RPV‐PW, p <.001). The LI drop and %LI drop cutoff values were 20.0 ohms and 11.6%, respectively. Conclusions: An insufficient LI drop with STABLEPOINT was associated with a gap formation during PVI, and the best cutoff values for the LI drop and %LI drop were 20.0 ohms and 11.6%, respectively. [ABSTRACT FROM AUTHOR]

Background: The local impedance (LI) is an emerging technology that monitors tissue‐catheter coupling during radiofrequency (RF) ablation. The relationships between the LI, RF delivery time, and lesion formation remain unclear. Methods: Using an LI‐enabled RF catheter in an ex vivo experimental model, RF lesions were created combined with various steps in the power (40 and 50 W), CF (10 g, 30 g, and 50 g), and time (10s, 20s, 30s, 40s, 50s, and 60s at 40 W and 5 s, 10s, 20s, 30s, 40s, 50s, and 60s at 50 W). The correlations between the LI drop, lesion size, and RF delivery time were evaluated. The rate of change in the time‐dependent gain in the LI, depth, and diameter and the time to reach 90% decay of the peak dY/dT (time to 90% decay) were assessed. Results: The correlation between the LI drop and ablation time revealed non‐linear changes. The time to a 90% decay in the LI drop differed depending on the RF ablation setting and was always shorter with the 50 W setting than 40 W setting. The LI drop always correlated with the lesion formation under all ablation power settings. Deeper or wider lesions were predominantly created within the time to 90% decay of the LI drop. Conclusion: The LI drop was useful for predicting lesion sizes. Deeper or wider lesions cannot be obtained with a longer ablation than the 90% decay time of the LI drop. A shorter ablation than the 90% decay time of the LI drop would be preferable for an effective ablation. [ABSTRACT FROM AUTHOR]

Background: Previous studies have identified noninvasive methods for predicting atrial fibrillation (AF) recurrence after catheter ablation (CA). We assessed the association between AF recurrence and atrial late potentials (ALPs), which were measured using P‐wave signal‐averaged electrocardiography (P‐SAECG). Methods: Consecutive patients with paroxysmal AF who underwent their first CA at our institution between August 2015 and August 2019 were enrolled. P‐SAECG was performed before CA. Two ALP parameters were evaluated: the root‐mean‐square voltage during the terminal 20 ms (RMS20) and the P‐wave duration (PWD). Positive ALPs were defined as an RMS20 <2.2 μV and/or a PWD >115 ms. Patients were allocated to either the recurrence or nonrecurrence group based on the presence of AF recurrence at the 1‐year follow‐up post‐CA. Results: Of the 190 patients (age: 65 ± 11 years, 37% women) enrolled in this study, 21 (11%) had AF recurrence. The positive ALP rate was significantly higher in the recurrence group than in the nonrecurrence group (86% vs. 64%, p =.04), despite the absence of differences in other baseline characteristics between the two groups. In the multivariate analysis, positive ALP was an independent predictor of AF recurrence (odds ratio: 3.83, 95% confidence interval: 1.05–14.1, p =.04). Conclusions: Positive ALP on pre‐CA P‐SAECG is associated with AF recurrence after CA. [ABSTRACT FROM AUTHOR]

A 48-year-old male with ischemic cardiomyopathy was admitted because of cardiogenic shock due to incessant ventricular tachycardia (VT). Despite the introduction of multiple mechanical cardiac support (MCS) devices, his hemodynamics were unstable; therefore, VT ablation was performed. Due to the limited vascular and left ventricle (LV) access with the multiple MCS devices, only the left femoral artery and vein were accessible. In addition, the transseptal approach as an LV access was difficult because of the MitraClip (Abbott Park, IL, USA). Posterior papillary muscle-origin VT was successfully treated via a transaortic approach under the MCS. After the VT ablation, the patient recovered from the MCS. Mechanical cardiac support (MCS) devices are critical during ventricular tachycardia (VT) ablation in patients with left ventricular (LV) dysfunction. However, the ablation strategy for cases with limited access due to multiple MCS devices has not been established. In this case, VT was successfully treated via a transaortic approach using intracardiac echocardiography. The number of cases requiring VT ablation for patients with limited vascular and LV endocardial access would increase; therefore, the accumulation of those cases is required to find a better strategy. [ABSTRACT FROM AUTHOR]

Aims: The analysis of heart rate (HR) changes, such as the HR variability or HR turbulence, has been reported as a marker of cardiovascular events during sinus rhythm; however, those relationships during atrial fibrillation (AF) remain controversial, and those parameters are not commonly used in AF patients. We sought to investigate the relationship between a simple index focused on the HR and heart failure (HF) events in patients with permanent AF. Methods and results: We enrolled 198 patients with permanent AF and evaluated the HR range, defined as the maximum HR minus the minimum HR on 24‐h Holter electrocardiogram recordings. The patients were divided into two groups, i.e., the larger (n = 101) and smaller (n = 97) HR range (HRR) groups, determined by the median value. The HF events were defined as hospitalizations for HF or urgent hospital visits due to exacerbations of one's HF status. The observation period of this study was set at 5 years from registration. The median age was 73 (68–77) years, and 29% were female. The median HRR was 84 (63–118) beats per minutes (bpm). During the observational period of 1825 days (median), HF events occurred in 37 (0.047 per patient‐year) patients. In a log‐rank test, the larger HRR group had more frequent HF events than the smaller HRR group (P = 0.0078). In the adjusted Cox proportional hazards model using the significantly different factors from the univariate analysis (Model 1) and factors and medications associated with HF (Model 2), the larger HRR group had a higher prevalence of HF events than the smaller HRR group for both models [Model 1, adjusted hazard ratio = 3.21, 95% confidence interval (CI) 1.593–6.708, P = 0.0009; Model 2, adjusted hazard ratio = 3.12, 95% CI 1.522–6.685, P = 0.002]. When analysed using the time‐dependent Cox proportional hazards model, the HRR was associated with HF with a statistically significant difference in both the univariate and multivariate analyses [hazard ratio = 1.01, 95% CI 1.006–1.020, P = 0.0002; Model 1, adjusted hazard ratio = 1.02, 95% CI 1.011–1.027, P < 0.0001; Model 2, adjusted hazard ratio = 1.01, 95% CI 1.008–1.021, P = 0.0003). There was no significant difference in the chronotropic medications between the two groups. Conclusions: In patients with permanent AF, a larger HRR was associated with HF events. [ABSTRACT FROM AUTHOR]

Introduction: Direct comparison studies about the incidence of esophagogastric complications between radiofrequency (RF) and cryoballoon (CB) catheter ablation (CA) for atrial fibrillation (AF) have been scarce. We sought to elucidate the relationship between the pulmonary vein isolation (PVI) modalities and esophagogastric complications. Methods: The study population consisted of 254 patients who underwent CA for AF from November 2017 to October 2018. Finally, 160 patients were enrolled and divided into the RF and CB groups. Esophageal ulcers, gastric hypomotility, and exfoliative esophagitis detected by esophagogastroduodenoscopy were defined as esophagogastric complications in this study. Results: The median age was 68 years old, with 34% being females. Esophagogastric complications were observed in 42.5% of patients who underwent CA. According to the detailed esophagogastric complications, the RF group had a higher prevalence of esophageal ulcers than the CB group (19% vs. 0%, p <.0001). There was no significant difference between the two groups regarding gastric hypomotility and exfoliative esophagitis (18% vs. 28%; p =.15 and 16% vs. 21%; p =.42, respectively). Conclusion: Asymptomatic esophagogastric complications were common in CA for AF. The incidence of esophageal ulcers was higher in the RF group than in the CB group, whereas the other esophagogastric complications did not significantly differ. [ABSTRACT FROM AUTHOR]

Background: Each direct oral anticoagulant (DOAC) has different dose reduction criteria. Here, we evaluated the differences in the doses of three anti‐Xa DOACs and clinical events based on the dose reduction criteria in patients with atrial fibrillation (AF). Methods: Consecutive AF patients prescribed with anti‐Xa DOACs [rivaroxaban (Riva), apixaban (Apix), and edoxaban (Edox)] between April 2011 and May 2016 were retrospectively evaluated. The incidences of thromboembolic and bleeding events were evaluated by the end of December 2020, focusing on the dose proportion. Results: A total of 786 patients (72 ± 10 years old, 66.9% male) were enrolled in this study [Riva (n = 337), Apix (n = 239), and Edox (n = 210)]. The proportion of reduced dose prescriptions was significantly greater for Edox (79.2%) than Riva (38.7%) or Apix (31.9%). A Kaplan–Meier analysis showed that the incidence of minor bleeding was significantly higher in the Apix than other groups (p <.001), even after propensity score matching. The standard dose of Apix had significantly higher bleeding events than the other DOACs (p <.001). Moreover, 23.2% and 51.6% of the patients with a standard dose of Apix were fulfilled with the dose reduction criteria for Riva and Edox and had more minor bleeding events than the unfulfilled ones (p =.046). Conclusions: The patients with a standard dose of Apix had a higher incidence of minor bleeding events than the other dosages. A reduced dose of apixaban was not prone to being chosen because of the dose reduction criteria, which may have been associated with a higher minor bleeding rate in patients with Apix. [ABSTRACT FROM AUTHOR]

Background: Local impedance (LI) can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). However, data on the effects of catheter contact angle on LI parameters are scarce. This study aimed to evaluate the influence of catheter contact angle on LI changes and lesion size with two different LI‐sensing catheters in a porcine experimental study. Methods: Lesions were created by the INTELLANAV MiFi™ OI (MiFi) and the INTELLANAV STABLEPOINT™ (STABLEPOINT). RFCA was performed with 30 W and a duration of 30 s. The contact force (CF) (0, 5, 10, 20, and 30 g) and catheter contact angle (30°, 45°, and 90°) were changed in each set (n = 8 each). The LI rise, LI drop, and lesion size were evaluated. Results: The LI rise increased as CF increased. There was no angular dependence with the LI rise under all CFs in the MiFi. On the other hand, the LI rise at 90° was lower than at 30° under 5 and 10 g of CF in STABLEPOINT. The LI drop increased as CF increased. Regarding the difference in catheter contact angles, the LI drop at 90° was lower than that at 30° for both catheters. The maximum lesion widths and surface widths were smaller at 90° than at 30°, whereas there were no differences in lesion depths. Conclusion: The LI drop and lesion widths at 90° were significantly smaller than those at 30°, although the lesion depths were not different among the 3 angles for the MiFi and STABLEPOINT. [ABSTRACT FROM AUTHOR]

Background: Local impedance (LI) has emerged as a new technology that informs on electrical catheter‐tissue coupling during radiofrequency (RF) ablation. Recently, IntellaNav StablePoint, a novel LI‐enabled catheter that equips contact force (CF) sensing, has been introduced. Although StablePoint and its predecessor IntellaNav MiFi OI share the common technology that reports LI, distinct mechanics for LI sensing between the two products raise a concern that the LI‐RF lesion formation relationship may differ. Methods: In an ex vivo swine cardiac tissue model, we investigated the initial level and range of a reduction in LI during a 60‐s RF ablation and the resultant lesion characteristics at nine combinations of three energy power (30, 40, and 50 W) and CF (10, 30, and 50 g) steps. Correlations and interactions between CF, LI, wattage, and formed lesions were analyzed. Incidence of achieving LI drop plateau and that of a steam pop were also determined. Results: Positive correlations existed between CF and initial LI, CF and absolute/relative LI drop, CF and lesion volume, and LI drop and lesion volume. At the same LI drop, wattage‐dependent gain in lesion volume was observed. Steam pops occurred in all CF steps and the prevalence was highest at 50 W. LI drop predicted a steam pop with a cutoff value at 89Ω. Conclusion: In StablePoint, wattage crucially affects LI drop and lesion volume. Because 30 W ablation may by underpowered for intramural lesion formation and 50 W often resulted in a steam pop, 40 W appears to achieve the balance between the safety and efficacy. [ABSTRACT FROM AUTHOR]

Objective: Patients with coronary artery disease (CAD) and atrial fibrillation (AF) can be treated with multiple antithrombotic therapies including antiplatelet and anticoagulant therapies; however, this has the potential to increase bleeding risk. Here, we aimed to evaluate the efficacy and safety of P2Y12 inhibitors and aspirin in patients also receiving anticoagulant therapy.Methods: We evaluated patients from the Atrial Fibrillation and Ischaemic Events with Rivaroxaban in Patients with Stable Coronary Artery Disease (AFIRE) trial who received rivaroxaban plus an antiplatelet agent; the choice of antiplatelet agent was left to the physician's discretion. The primary efficacy and safety end points, consistent with those of the AFIRE trial, were compared between P2Y12 inhibitors and aspirin groups. The primary efficacy end point was a composite of stroke, systemic embolism, myocardial infarction, unstable angina requiring revascularisation or death from any cause. The primary safety end point was major bleeding according to the International Society on Thrombosis and Haemostasis criteria.Results: A total of 1075 patients were included (P2Y12 inhibitor group, n=297; aspirin group, n=778). Approximately 60% of patients were administered proton pump inhibitors (PPIs) and there was no significant difference in PPI use in the groups. There were no significant differences in the primary end points between the groups (efficacy: HR 1.31; 95% CI 0.88 to 1.94; p=0.178; safety: HR 0.79; 95% CI 0.43 to 1.47; p=0.456).Conclusions: There were no significant differences in cardiovascular and bleeding events in patients with AF and stable CAD taking rivaroxaban with P2Y12 inhibitors or aspirin in the chronic phase.Trial Registration Number: UMIN000016612; NCT02642419. [ABSTRACT FROM AUTHOR]

Background: The local impedance (LI) reflects the electrical catheter‐tissue coupling and correlates with the local tissue temperature. However, there have been few clinical studies showing the recommended method for LI monitoring catheters. This study aimed to investigate the optimal ablation setting for this catheter in an in vitro experimental model. Methods: LI monitoring catheters were used in an excised swine heart experimental model. The tissue contact force (CF) was directly monitored from an external weight scale. Radiofrequency ablation was performed with a combination of various energy power settings (30, 40, and 50 W), and various CFs (10, 30, and 50 g) for 60 s. The correlation between the LI‐related indexes, power, and CF with the lesion formation was statistically analyzed. Results: A positive correlation between the LI or lesion formation and CF was observed under all powers. Although the LI drop always correlated with the maximum lesion depth, lesion diameter, and lesion volume, the coefficient of the correlation value was lower under a high CF (lesion depth, diameter, and volume; 10 g, r = 0.8064, r = 0.8389, r = 0.8477; 30 g, r = 0.7590, r = 0.8063, r = 0.8060; 50 g r = 0.5555, r = 0.5701, and r = 0.5678, respectively). Steam pops occurred only under a 50 W ablation and the LI drop cutoff value for steam pops was 46 Ω. Conclusion: The same LI drop did not always lead to the same lesion size when the CF differed. Monitoring the LI and not exceeding 46 Ω would be useful for a safe ablation. [ABSTRACT FROM AUTHOR]

Background: Although the lesion size index (LSI) has been well established, it is sometimes difficult to achieve first‐pass pulmonary vein isolation (PVI) and to avoid acute pulmonary vein reconnections, even with LSI‐guided procedures. The purpose of this study was to assess the predictive accuracy of a novel parameter, the optimized lesion size index (o‐LSI), to perform PVI. Methods: The voltage maps created by the Advisor™ high‐density (HD) grid catheter before PVI in 35 atrial fibrillation (AF) patients were examined for an association between the voltage amplitude and insufficient ablation sites (IAS), which were defined as either (i) spontaneous reconnection sites, (ii) dormant PV conduction sites unmasked with 20 mg of adenosine triphosphate disodium hydrate (ATP) injection, or (iii) PV‐LA gap sites after the initial PVI. Results: IAS was observed in 25/1417 of the total ablation sites. IAS was significantly associated with higher bipolar voltage areas (4.20 ± 2.68 vs 2.43 ± 1.93 mV, P <.0001) but not with LSI. A novel index, o‐LSI (defined as LSI/bipolar voltage), was significantly lower in IAS than in others (1.14 [0.82, 1.81] vs 2.35 [1.31, 4.80] LSI/mV). By receiver operating characteristic analysis, an o‐LSI of 2.04 was the best cutoff value for the prediction of IAS (88% sensitivity and 55% specificity, P <.0001, areas under the curve: 0.742). Conclusion: Low o‐LSI was strongly associated with IAS, potentially providing a novel index to improve first‐pass PV isolation. [ABSTRACT FROM AUTHOR]

Whether ablation for atrial fibrillation (AF) is, in terms of clinical outcomes, beneficial for Japanese patients has not been clarified. Drawing data from 2 Japanese AF registries (AF Frontier Ablation Registry and SAKURA AF Registry), we compared the incidence of clinically relevant events (CREs), including stroke/transient ischemic attack (TIA), major bleeding, cardiovascular events, and death, between patients who underwent ablation (n = 3451) and those who did not (n = 2930). We also compared propensity-score matched patients (n = 1414 in each group). In propensity-scored patients who underwent ablation and those who did not, mean follow-up times were 27.2 and 35.8 months, respectively. Annualized rates for stroke/TIA (1.04 vs. 1.06%), major bleeding (1.44 vs. 1.20%), cardiovascular events (2.15 vs. 2.49%) were similar (P = 0.96, 0.39, and 0.35, respectively), but annualized death rates were lower in the ablation group than in the non-ablation group (0.75 vs.1.28%, P = 0.028). After multivariate adjustment, the risk of CREs was statistically equivalent between the ablation and non-ablation groups (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.71–1.11), but it was significantly low among patients who underwent ablation for paroxysmal AF (HR 0.68 [vs. persistent AF], 95% CI 0.49–0.94) and had a CHA2DS2-VASc score < 3 (HR 0.66 [vs. CHA2DS2-VASc score ≥ 3], 95% CI 0.43–0.98]). The 2-year risk reduction achieved by ablation may be small among Japanese patients, but AF ablation may benefit those with paroxysmal AF and a CHA2DS2-VASc score < 3. [ABSTRACT FROM AUTHOR]

Gastric hypomotility (GH) is a possible complication of catheter ablation (CA) for atrial fibrillation (AF). However, it is unclear which factors are associated with GH. We sought to elucidate the relationship between the CA procedure and GH. The study population consisted of 254 patients who underwent CA for AF from November 2017 to October 2018. Finally, 119 patients were enrolled and divided into two groups: with or without GH (GH or non-GH groups). To evaluate the association with GH, the clinical backgrounds and procedure characteristics of the radiofrequency CA (RFCA) were compared between the two groups. The median age was 69 years old with 34% of female. GH were observed in 27.7% of patients who underwent RFCA, which was significantly higher than that in the cohort of patients who underwent esophago-gastro-duodenoscopy during the same time period (1.9%: 151 in 8063 patients, p < 0.0001). According to the detailed RFCA procedure, additional posterior wall isolation with pulmonary vein isolation (PVI) had a higher prevalence of GH than that with only PVI (54.8% vs. 18.2%; odds ratio 5.46, 95%CI 2.24–13.32, p = 0.0002). After an adjustment using a multivariate logistic analysis, a posterior wall isolation with the PVI was identified as the only independent predictor for GH (odds ratio 5.01, 95%CI 1.94–13.43, p = 0.0009). Additional posterior wall isolation with PVI was associated with gastric hypomotility. • Gastric hypomotility (GH) is an important complication during AF ablation. • We evaluated the incidence of GH after the index catheter ablation (CA). • The GH was highly observed after the CA than general populations (27.7% vs. 1.9%). • Additional posterior wall isolation was the independent risk factor for GH. [ABSTRACT FROM AUTHOR]

Background: Right ventricular (RV) pacing causes left ventricular (LV) dyssynchrony sometimes resulting in pacing‐induced cardiomyopathy. However, RV pacing for hypertrophic obstructive cardiomyopathy is one of the treatment options. LV flow energy loss (EL) using vector flow mapping (VFM) is a novel hemodynamic index for assessing cardiac function. Our study aimed to elucidate the impact of RV pacing on EL in normal LV function and hypertrophic cardiomyopathy (HCM) patients. Methods: A total of 36 patients with dual‐chamber pacemakers for sick sinus syndrome or implantable cardioverter defibrillators for fatal ventricular tachyarrhythmias were enrolled. All patients were divided into two groups: 16 patients with HCM (HCM group) and others (non‐HCM group). The absolute changes in EL under AAI (without RV pacing) and DDD (with RV pacing) modes were assessed using VFM on color Doppler echocardiography. Results: In the non‐HCM group, the mean systolic EL significantly increased from the AAI to DDD modes (14.0 ± 7.7 to 17.0 ± 8.6 mW/m, P =.003), whereas the mean diastolic EL did not change (19.0 ± 12.3 to 17.0 ± 14.8 mW/m, P =.231). In the HCM group, the mean systolic EL significantly decreased from the AAI to DDD modes (26.7 ± 14.2 to 21.6 ± 11.9 mW/m, P <.001), whereas the mean diastolic EL did not change (28.7 ± 16.4 to 23.9 ± 19.7 mW/m, P =.130). Conclusions: RV pacing increased the mean systolic EL in patients without HCM. Conversely, RV pacing decreased the mean systolic EL in patients with HCM. [ABSTRACT FROM AUTHOR]

A 61-year-old male was referred to our hospital to receive catheter ablation of paroxysmal atrial fibrillation. Since no anatomical abnormalities were detected by preoperative computed tomography of left atrium and pulmonary veins (PVs), he underwent a cryoballoon ablation for a PV isolation. We performed single, 3-min freeze applications to all four PVs while monitoring the esophageal temperature. Immediately after the procedure, he complained of nausea, followed by a body weight loss of 9 kg over 2 months. Since no structural abnormalities were detected even through careful evaluation, he was diagnosed with hypoperistalsis caused by the cryoballoon ablation. Although his symptoms partially improved, they persisted over a year. The cryoballoon procedure is believed to be relatively safe, but even just a simple 3-min freeze application caused severe hypoperistalsis in the present case. Operators should recognize the risk of such complications. < Learning objective: Cryoballoon ablation is thought to be a safe procedure, however, there are important complications. Asymptomatic or mild-symptomatic hypoperistalsis after cryoballoon ablation is not uncommon. In this case, even just a single 3-min freeze for each pulmonary vein caused severe hypoperistalsis. Repetitive or longer freezes are reported as a risk for this complication, therefore, the operator should recognize the risk of this complication, and a shorter freeze time may be considered instead of a fixed 3-min freeze.> [ABSTRACT FROM AUTHOR]

Key Clinical Message: Esophageal injury is a major concern during catheter ablation of atrial fibrillation. Operators avoid radiofrequency applications on the esophagus by changing ablation line; however, it is unavoidable in patients with a dilated esophagus, such as esophageal achalasia. Steerable esophageal thermometer is useful for evaluating precise temperatures to prevent esophageal injury. [ABSTRACT FROM AUTHOR]

Background Cardiac troponin T (cTnT) has been reported to be associated with cardiac mortality. In the present study, we evaluated the role of routine assessment of cTnT as a predictor of future cardiac death in patients with left ventricular (LV) dysfunction. Methods Patients who were eligible for prophylactic implantable cardioverter defibrillator (ICD) were included from cardiac catheterization database. Inclusion criteria were patients with LV ejection fraction of ≤ 35% and with New York Heart Association (NYHA) ≥class II. Exclusion criteria were patients with acute coronary syndrome, ICD for secondary prevention, NYHA class IV, and lack of data. The final study patients were divided into the following three groups in accordance with two quartile points of serum cTnT levels: low cTnT, intermediate cTnT, and high cTnT groups. The primary endpoint of this study was cardiac death. Results A total of 70 patients were included (mean age, 62±13 years; male individuals, 56; ischemic, 36; and non-ischemic, 34). During the observation period of 2.2 years, cardiac death was observed in 17 patients (fatal arrhythmic event, 9; heart failure, 7; myocardial infarction, 1). In the Kaplan–Meier analysis, the high cTnT group showed the highest risk among all the groups ( p <0.001). Even in sub-analyses for ischemic and non-ischemic patients, the results were the same, and the high cTnT group showed the highest event rate ( p <0.05). In contrast, no cardiac death was observed in the low cTnT group. Conclusion The cTnT levels in a stable state were associated with cardiac death in patients with LV dysfunction, even in those with non-ischemic diseases. [ABSTRACT FROM AUTHOR]

A seventy year-old male was referred to our hospital to undergo radiofrequency catheter ablation (RFCA) for drug-refractory paroxysmal atrial fibrillation (AF). Pre-operative three-dimensional computed tomography revealed a unique left atrial (LA) roof vein. Electrophysiological findings showed expansion of the myocardial sleeve and local firing in the LA roof vein. We performed isolation of this arrhythmogenic abnormal vein concomitant with general pulmonary vein isolation in this case, and AF did not recur after the procedure. [ABSTRACT FROM AUTHOR]

Background Dabigatran etexilate (DE), an effective direct oral anticoagulant for patients with atrial fibrillation (AF), should be carefully used in patients with renal insufficiency. Data on the safety of DE in Japanese “real world” patients with mildly impaired renal function are limited. We hypothesized that low-dose DE (110 mg, twice daily) could be safely used in Japanese AF patients with mildly impaired renal function compared to those with preserved renal function. Methods and results One hundred ninety-six consecutive AF patients taking low-dose DE were retrospectively enrolled in this study, and were divided into two groups: preserved creatinine clearance (CCr ≥50 ml/min; n = 127) and reduced CCr (30–49 ml/min; n = 69). Baseline characteristics including CHADS 2 , CHA 2 DS 2 -VASc, and HAS-BLED scores were evaluated. Activated partial thromboplastin time (aPTT) was measured as a surrogate marker of the anticoagulant activity of DE, which was evaluated at 661 time points in total and the data were divided into five time windows after the last DE intake. The incidence of bleeding complications was compared between the two groups of reduced and preserved CCr. Reduced CCr group showed higher age (76.9 ± 6.3 years vs. 67.6 ± 6.7 years), higher CHADS 2 (2.6 ± 1.4 vs. 1.8 ± 1.2), higher CHA 2 DS 2 -VASc (4.3 ± 1.6 vs. 3.2 ± 1.6), and higher HAS-BLED (2.3 ± 1.0 vs. 2.0 ± 1.0) scores in comparison with preserved CCr group ( p < 0.01, respectively). There was no difference in aPTT over the entire time windows between the two groups. The incidence of total bleeding events was not significantly different between the two groups (reduced vs. preserved CCr = 2/69 vs. 2/127). Conclusion Low-dose DE was safe in AF patients with mildly reduced CCr. [ABSTRACT FROM AUTHOR]