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Introduction: Posterior wall isolation (PWI) combined with pulmonary vein isolation (PVI) has proven effective for persistent atrial fibrillation (AF). However, when performing PWI, creating transmural lesions with subendocardial ablation is sometimes difficult. Endocardial unipolar voltage amplitude had a higher sensitivity than bipolar voltage mapping for identifying intramural viable myocardium in the atria. In this study, we aimed to retrospectively investigate the correlation between the residual potential in the posterior wall (PW) following PWI for persistent AF and atrial arrhythmia recurrence using endocardial unipolar voltage. Methods: This was a single‐center observational study. Patients who underwent PVI and PWI for persistent AF in the first procedure between March 2018 and December 2021 at the Tokyo Metropolitan Hiroo Hospital were included in this study. The patients were divided into two groups based on the presence of residual unipolar PW potentials after PWI with a cutoff of 1.08 mV and the recurrence of atrial arrhythmias was compared. Results: In total, 109 patients were included in the analysis. Forty‐three patients had residual unipolar potentials after PWI and 66 patients had no residual unipolar potentials. The atrial arrhythmia recurrence rate was significantly higher in the group with residual unipolar potential (41.8% vs. 17.9%, p = 0.003). The residual unipolar potential was an independent predictor of recurrence (odds ratio: 4.53; confidence interval: 1.67–12.3, p = 0.003). Conclusion: Residual unipolar potential after PWI for persistent AF is associated with recurrent atrial arrhythmias. [ABSTRACT FROM AUTHOR]

Although it is common for bi‐atrial tachycardia (AT) circuits to include the Bachmann bundle, there are few reports of its role in left AT circuits. A 77‐year‐old man was admitted for recurrent AT with a cycle length of 425 ms. The endocardial and epicardial activation map revealed an AT circuit located in the left atrial anterior wall and transverse pericardial sinus, showing a centrifugal pattern stemming from the left atrial appendage. After radiofrequency ablation, AT was no longer induced. This case suggests that the Bachmann bundle may be part of the left AT circuit. [ABSTRACT FROM AUTHOR]

Introduction: In patients with prior atrial septal defect (ASD) closure and atrial tachyarrhythmias, transseptal puncture can be challenging. Methods and Results: This case report discusses a 65‐year‐old man who had previously undergone pulmonary vein isolation (PVI) and cavo‐tricuspid isthmus ablation for atrial fibrillation before ASD closure, respectively. He developed atrial tachycardia (AT) and underwent catheter ablation. AT was diagnosed as peri‐mitral flutter and the mitral isthmus (MI) linear ablation via a trans‐aortic approach successfully terminated it. Conclusion: This case demonstrates the feasibility and safety of transaortic MI linear ablation in patients with ASD closure devices or anatomical challenges when transseptal puncture is difficult. [ABSTRACT FROM AUTHOR]

T‐wave oversensing in pacemakers is rare because the set sensitivity is generally fixed. However, several models of pacemaker employ automatic sensitivity adjustment. Here, we present two cases of atrioventricular block treated by implantation of the pacemaker with automatic sensitivity adjustment. After implanting the pacemaker with automatic sensitivity adjustment, ventricular pacing suppression due to T‐wave oversensing occurred. In both cases, T‐wave oversensing disappeared after adjusting the setting sensitivity from 0.9 to 2.0 mV. [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]

Excimer laser coronary atherectomy (ELCA) is an effective treatment to remove intracoronary thrombi. In the present study, we compared in-hospital mortality in patients with acute myocardial infarction (AMI) who underwent conventional treatment and conventional treatment plus ELCA. Among 656 patients who were admitted to our hospital through the Tokyo CCU Network, 104 patients with AMI who were treated by percutaneous coronary intervention between January 2013 and December 2016 met inclusions criteria and underwent conventional treatment with ELCA (ELCA group) and 89 underwent conventional treatment alone (conventional group). We retrospectively evaluated in-hospital mortality within 30 days and used propensity score (PS) matching to reduce assignment bias and multivariate analysis to detect the predictors of in-hospital mortality. In-hospital mortality rate was significantly lower in the ELCA group before and after PS matching (2.9% vs. 13.5%, p = 0.006 before PS matching, and 2.8% vs. 14.1%, p = 0.016 after PS matching). After PS matching, β-blocker or statins use, incidence of shock, Killip classification, and door-to-balloon time were not significantly different. A multivariate logistic regression analysis identified ELCA, dyslipidemia, shock, and left ventricular ejection fraction as independent predictors of in-hospital mortality (odds ratio (OR), 0.147, 95% confidence interval [CI], 0.022–0.959, p = 0.045; OR, 0.077, 95% CI, 0.007–0.805, p = 0.032; OR, 6.494, 95% CI, 1.228–34.34, p = 0.028; OR, 0.890, 95% CI, 0.828–0.957, p = 0.002, respectively). Our data indicate that ELCA with the small diameter and low level emission may reduce the in-hospital mortality compared to conventional methods in patients with AMI in drug-eluting stent era. [ABSTRACT FROM AUTHOR]