Background-In patients with atrial fibrillation (AF) undergoing radiofrequency (RF) electrical disconnection of multiple pulmonary veins (PVs), the incidence of late conduction recurrences has not been systematically determined. Methods and Results-Using a prospectively designed, multistep approach, we aimed at assessing the correlation between acute achievement and chronic maintenance of electrical conduction block across RF lesions disconnecting the distal tract of the PV in 43 patients (52.3Ϯ8.2 years) with AF.

Background The HeartLogic algorithm measures data from multiple implantable cardioverter‐defibrillator‐based sensors and combines them into a single index. The associated alert has proved to be a sensitive and timely predictor of impending heart failure (HF) decompensation. Hypothesis We describe a multicenter experience of remote HF management by means of HeartLogic and appraise the value of an alert‐based follow‐up strategy. Methods The alert was activated in 104 patients. All patients were followed up according to a standardized protocol that included remote data reviews and patient phone contacts every month and at the time of alerts. In‐office examinations were performed every 6 months or when deemed necessary. Results During a median follow‐up of 13 (10–16) months, the overall number of HF hospitalizations was 16 (rate 0.15 hospitalizations/patient‐year) and 100 alerts were reported in 53 patients. Sixty alerts were judged clinically meaningful, and were associated with multiple HF‐related conditions. In 48 of the 60 alerts, the clinician was not previously aware of the condition. Of these 48 alerts, 43 triggered clinical actions. The rate of alerts judged nonclinically meaningful was 0.37/patient‐year, and the rate of hospitalizations not associated with an alert was 0.05/patient‐year. Centers performed remote follow‐up assessments of 1113 scheduled monthly transmissions (10.3/patient‐year) and 100 alerts (0.93/patient‐year). Monthly remote data review allowed to detect 11 (1%) HF events requiring clinical actions (vs 43% actionable alerts, P < .001). Conclusions HeartLogic allowed relevant HF‐related clinical conditions to be identified remotely and enabled effective clinical actions to be taken; the rates of unexplained alerts and undetected HF events were low. An alert‐based management strategy seemed more efficient than a scheduled monthly remote follow‐up scheme.

Aims In the Multisensor Chronic Evaluation in Ambulatory Heart Failure Patients study, a novel algorithm for heart failure (HF) monitoring was implemented. The HeartLogic (Boston Scientific) index combines data from multiple implantable cardioverter defibrillator (ICD)‐based sensors and has proved to be a sensitive and timely predictor of impending HF decompensation. The remote monitoring of HF patients by means of HeartLogic has never been described in clinical practice. We report post‐implantation data collected from sensors, the combined index, and their association with clinical events during follow‐up in a group of patients who received a HeartLogic‐enabled device in clinical practice. Methods and results Patients with ICD and cardiac resynchronization therapy ICD were remotely monitored. In December 2017, the HeartLogic feature was activated on the remote monitoring platform, and multiple ICD‐based sensor data collected since device implantation were made available: HeartLogic index, heart rate, heart sounds, thoracic impedance, respiration, and activity. Their association with clinical events was retrospectively analysed. Data from 58 patients were analysed. During a mean follow‐up of 5 ± 3 months, the HeartLogic index crossed the threshold value (set by default to 16) 24 times (over 24 person‐years, 0.99 alerts/patient‐year) in 16 patients. HeartLogic alerts preceded five HF hospitalizations and five unplanned in‐office visits for HF. Symptoms or signs of HF were also reported at the time of five scheduled visits. The median early warning time and the time spent in alert were longer in the case of hospitalizations than in the case of minor events of clinical deterioration of HF. HeartLogic contributing sensors detected changes in heart sound amplitude (increased third sound and decreased first sound) in all cases of alerts. Patients with HeartLogic alerts during the observation period had higher New York Heart Association class ( P = 0.025) and lower ejection fraction ( P = 0.016) at the time of activation. Conclusions Our retrospective analysis indicates that the HeartLogic algorithm might be useful to detect gradual worsening of HF and to stratify risk of HF decompensation.

Background: Atrial fibrillation (AF) ablation outcome is still operator dependent. Ablation Index (AI) is a new lesion quality marker that has been demonstrated to allow acute durable pulmonary vein (PV) isolation followed by a high single-procedure arrhythmia-free survival.This prospective, multicenter study was designed to evaluate the reproducibility of acute PV isolation guided by the AI.Methods: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV encircling and were divided in four study groups according to operator preference in choosing the ablation catheter (a contact force [ST] or contact force surround flow [STSF] catheter) and the AI setting (330 at posterior and 450 at anterior wall or 380 at posterior and 500 at anterior wall). Radiofrequency was delivered targeting interlesion distance ≤6 mm. Results:The rate of first-pass PV isolation (ST330 90 ± 16%, ST380 87 ± 19%, STSF330 90 ± 17%, STSF380 91 ± 15%, P = .585) was similar among the four study groups, whereas procedure (ST330 129 ± 44 minutes, ST380 144 ± 44 minutes, STSF330 120 ± 72 minutes, STSF380 125 ± 73 minutes, P < .001) and fluoroscopy time (ST330 542 ± 285 seconds, ST380 540 ± 416 seconds, STSF330 257 ± 356 seconds, STSF380 379 ± 454 seconds, P < 0.001) significantly differed. The difference in the rate of first-pass isolation was not statistical different (P = .06) among the 12 operators that performed at least 15 procedures. Conclusions:An ablation protocol respecting strict criteria for contiguity and quality lesion results in high and comparable rate of acute PV isolation among operator performing ablation with different catheters, AI settings, procedure, and fluoroscopy times. K E Y W O R D S ablation index, atrial fibrillation, catheter ablation, reproducibility 874

Background Highly localized impedance (LI) measurements during atrial fibrillation (AF) ablation have recently emerged as a viable real‐time indicator of tissue characteristics and durability of the lesions created. We report the outcomes of acute and long‐term clinical evaluation of the new DirectSense algorithm in AF ablation. Methods Consecutive patients undergoing AF ablation were included in the CHARISMA registry. RF delivery was guided by the DirectSense algorithm, which records the magnitude and time‐course of the impedance drop. The ablation endpoint was pulmonary vein isolation (PVI), as assessed by the entrance and exit block. Results 3556 point‐by‐point first‐pass RF applications of >10 s duration were analyzed in 153 patients (mean age=59 ± 10 years, 70% men, 61% paroxysmal AF, 39% persistent AF). The mean baseline LI was 105 ± 15 Ω before ablation and 92 ± 12 Ω after ablation (p < .0001). Both absolute drops in LI and the time to LI drop (LI drop/τ) were greater at successful ablation sites (n = 3122, 88%) than at ineffective ablation sites (n = 434, 12%) (14 ± 8 Ω vs 6 ± 4 Ω, p < .0001 for LI; 0.73 [0.41–1.25] Ω/s vs. 0.35[0.22–0.59 Ω/s, p < .0001 for LI drop/τ). No major complications occurred during or after the procedures. All PVs had been successfully isolated. During a mean follow‐up of 366 ± 130 days, 18 patients (11.8%) suffered an AF/atrial tachycardia recurrence after the 90‐day blanking period. Conclusion The magnitude and time‐course of the LI drop during RF delivery were associated with effective lesion formation. This ablation strategy for PVI guided by LI technology proved safe and effective and resulted in a very low rate of AF recurrence over 1‐year follow‐up.