Aims Atrial fibrillation (AFib) induces remodelling of the left atrium (LA). Indexed LA volume (iLAV) as more accurate measure of LA size has not been evaluated as predictor of recurrence of AFib after cardioversion. Methods and results We identified 411 adults (mean age 64.1 ± 11.4 years, 34.5% women) who underwent successful cardioversion and with no history of other atrial arrhythmia, stroke, congenital heart disease, valvular dysfunction, surgery, thyroid dysfunction, acute or chronic inflammatory disease, and pacemaker. All echocardiographic data were retrieved from the laboratory database. iLAV was measured off-line using Simpson's method. Clinical characteristics and recurrence of clinical AFib were determined by review of medical records. Patients with scheduled follow-up of at least 6 months were included. About 250 patients (60.8%) developed AFib recurrence after a median (25th–75th percentile) follow-up of 345.0 (210.0–540.0) days. Patients with AFib recurrence had significantly greater iLAV than patients without AFib recurrence (39.7 ± 8.4 vs. 31.4 ± 4.6, P < 0.001). Each mL/m2 increase in iLAV was associated with a 30% increased risk of AFib recurrence [odds ratio (OR) 1.30, confidence interval (CI) 1.23–1.38, P < 0.001]. In a multivariable model, each mL/m2 increase in iLAV was independently associated with a 21% increase in the risk of AFib recurrence (OR 1.21, CI 1.11–1.30, P < 0.001). The areas under receiver operating characteristic curves, generated to compare LA diameter and iLAV as predictors of AFib recurrence, were 0.59 ± 0.3 and 0.85 ± 0.2, respectively ( P < 0.001). Conclusion The present study is the first to show that larger iLAV before cardioversion, as a more accurate measure of LA remodelling than LA diameter, is strongly and independently associated with higher risks of AFib recurrence.

Background: Although indexed left atrial volume (iLAV) is the most accurate measure of left atrial size, it has not been evaluated prospectively as predictor of recurrence of atrial fibrillation (AFib) after successful cardioversion (CV). Methods: We prospectively selected 76 patients (mean age 66.1 ± 13.6 years, 65.8% men) with AFib who underwent successful CV. Baseline clinical and echocardiographic characteristics were obtained before CV. LAV was measured using Simpson's method and indexed to body surface area. All patients were scheduled for follow‐up visit at 1, 6, 12 months, and then annually. A 24‐hour Holter ECG was performed within 6 months and each time the patients reported symptoms suggestive of arrhythmia. Results: The 52 patients (68.4%) with AFib recurrence had larger iLAV (35.5 ± 8.9 mL/m² vs 27.0 ± 6.7 mL/m², P < 0.001). Anteroposterior LA diameter was not associated with AFib relapse (OR 1.08, 95% CI: 0.96–1.21, P = 0.09). Each unit increase in iLAV was associated with a 1.15‐fold increased risk of recurrence (OR 1.15, 95% CI: 1.06–1.25, P < 0.001). In a multivariable model, iLAV remained the only independent predictor of relapse (adjusted OR 1.14, 95% CI: 1.02–1.28, P = 0.02). The area under ROC curves, generated to compare LA diameter, and iLAV as predictors of AFib recurrence were 0.56 (SE 0.07) versus 0.78 (SE 0.05), respectively (P = 0.003). Conclusion: This is the first prospective study to show that larger iLAV, as a more accurate measure of LA remodeling than anteroposterior diameter, is strongly and independently associated with a higher risk of AFib recurrence after CV. (Echocardiography 2012;29:276‐284)

Infections resulting from cardiac implantable electronic device (CIED) implantation are severely impacting on patients’ and on health care systems. The use of TYRX^TM absorbable antibiotic-eluting envelope has proven to decrease major CIED infections within 12 months of CIED surgery. The aim is to evaluate the impact of the envelope use on infection-related clinical events in a real-world contemporary patient population. Data on patients undergoing CIED surgery were collected prospectively by participating centers of the One Hospital ClinicalService project. Patients were divided into two groups according to whether TYRX^TM absorbable antibiotic-eluting envelope was used or not. Out of 1819 patients, 872 (47.9%) were implanted with an absorbable antibiotic-eluting envelope and included in the Envelope group and 947 (52.1%) patients who did not receive an envelope were included in the Control group. Compared to control, patients in the Envelope group had higher thrombo-embolic or hemorrhagic risk, higher BMI, lower LVEF and more comorbidities. During a mean follow-up of 1.4 years, the incidence of infection-related events was significantly higher in the control compared to the Envelope group (2.4% vs. 0.8%, P = 0.007). The five-year cumulative incidence of infection-related events was 8.1% in the control and 2.1% in the Envelope group (HR: 0.34, 95%CI: 0.14–0.80, P = 0.010). In our analysis, the use of an absorbable antibiotic-eluting envelope in the general CIED population was associated with a lower risk of systemic and pocket infection.

Introduction: The assessment of the ventricular myocardial substrate critically depends on the size of mapping electrodes, their orientation with respect to wavefront propagation, and interelectrode distance. We conducted a dual‐center study to evaluate the impact of microelectrode mapping in patients undergoing catheter ablation (CA) of ventricular tachycardia (VT).Methods: We included 21 consecutive patients (median age, 68 [12], 95% male) with structural heart disease undergoing CA for electrical storm (n = 14) or recurrent VT (n = 7) using the QDOT Micro catheter and a multipolar catheter (PentaRay, n = 9). The associations of peak‐to‐peak maximum standard bipolar (BV_c) and minibipolar (PentaRay, BV_p) with microbipolar (BV_μMax) voltages were respectively tested in sinus rhythm with mixed effect models. Furthermore, we compared the features of standard bipolar (BE) and microbipolar (μBE) electrograms in sinus rhythm at sites of termination with radiofrequency energy.Results: BV_μMax was moderately associated with both BV_c (β = .85, p < .01) and BV_p (β = .56, p < .01). BV_μMax was 0.98 (95% CI: 0.93−1.04, p < .01) mV larger than corresponding BV_c, and 0.27 (95% CI: 0.16−0.37, p < .01) mV larger than matching BVp in sinus rhythm, with higher percentage differences in low voltage regions, leading to smaller endocardial dense scar (2.3 [2.7] vs. 12.1 [17] cm², p < .01) and border zone (3.2 [7.4] vs. 4.8 [20.1] cm², p = .03) regions in microbipolar maps compared to standard bipolar maps. Late potentials areas were nonsignificantly greater in microelectrode maps, compared to standard electrode maps. At sites of VT termination (n = 14), μBE were of higher amplitude (0.9 [0.8] vs. 0.4 [0.2] mV, p < .01), longer duration (117 [66] vs. 74 [38] ms, p < .01), and with greater number of peaks (4 [2] vs. 2 [1], p < .01) in sinus rhythm compared to BE.Conclusion: microelectrode mapping is more sensitive than standard bipolar mapping in the identification of viable myocytes in SR, and may facilitate recognition of targets for CA.

Cardiac amyloidosis may result in an aggressive form of heart failure (HF). Cardiac contractility modulation (CCM) has been shown to be a concrete therapeutic option in patients with symptomatic HF, but there is no evidence of its application in patients with cardiac amyloidosis. We present the case of TTR amyloidosis, where CCM therapy proved to be effective. The patient had a history of multiple HF hospitalizations due to an established diagnosis of wild type TTR-Amyloidosis with significant cardiac involvement. Since he was highly symptomatic, except during continuous dobutamine and diuretic infusion, it was opted to pursue CCM therapy device implantation. At follow up, a significant improvement in clinical status was reported with an increase of EF, functional status (6 min walk test improved from zero meters at baseline, to 270 m at 1 month and to 460 m at 12 months), and a reduction in pulmonary pressures. One year after device implantation, no other HF hospital admission was needed. CCM therapy may be effective in this difficult clinical setting. The AMY-CCM Registry, which has just begun, will evaluate the efficacy of CCM in patients with HF and diagnosed TTR amyloidosis to bring new evidence on its potential impact as a therapeutic option.

BACKGROUND: Retrograde ethanolization of the vein of Marshall (VOM) has been identified as an adjunct technique in the treatment of persistent atrial fibrillation (AF) and left atrial tachycardia, as stated in the last consensus statement on ablation of AF. However, there is a lack of high-volume data on the technique. METHODS: Through the collection of data from worldwide centers, we performed this international survey that aims to analyze the safety and procedural characteristics of VOM ethanolization in patients referred for treatment of AF or left atrial tachycardia. RESULTS: We included 5579 patients (66 years; range, 20–93) from 26 centers, who underwent VOM ethanolization between 2008 and 2024 for persistent AF (81%), paroxysmal AF (9%), or left atrial tachycardia (10%) under deep sedation (53%) or general anesthesia (47%). A concomitant mitral isthmus line was attempted in 79% of the cases, achieving mitral isthmus block in 98% of patients. There were 0.92% of periprocedural serious adverse events, including 0.09% of peri-procedural death (5 patients). Three patients developed hemodynamic collapse immediately after VOM ethanolization, causing the death of 1 due to anaphylactic shock. One patient died following surgical drainage of pericardial effusion 3 weeks after the procedure. The 3 other deaths were not directly related to VOM ethanolization. Pericardial effusion was observed in 123 patients (2.2%) at the time of or immediately after the procedure, requiring drainage in 20 patients (0.36%) and later in 32 additional patients (0.57%), including 5 (0.09%) requiring drainage. Pacemaker implantation was required in 2 patients (0.04%), 1 for high-grade atrioventricular block and 1 for sinus node dysfunction. CONCLUSIONS: This international survey shows that VOM ethanolization is predominantly performed in patients with persistent AF. It is associated with rare but potentially life-threatening adverse events. Mitral isthmus line ablation results in a very high rate of block when performed concomitantly.