Catheter ablation (CA) is an effective treatment for ventricular tachycardia (VT), but its role in elderly non-ischemic cardiomyopathy (NICM) patients remains unclear. We aim to evaluate the feasibility of VT ablation in this population by comparing outcomes with elderly ischemic cardiomyopathy (ICM) patients. We retrospectively analyzed patients ≥ 70 years with structural heart disease who underwent VT ablation at a tertiary center from 2016 to 2024. Patients were categorized as NICM (n = 52) or ICM (n = 70), and demographic, mapping, procedural, and long-term outcomes were compared. The mean age was 76.5 ± 5.2 and 76.6 ± 4.6 years in the NICM and ICM groups. The baseline demographic data were not different except for a lower left ventricular (LV) ejection fraction in the ICM group. The LV substrate map showed larger overall scars in ICM, whereas NICM had a relatively larger unipolar than bipolar scar, suggesting intramural substrate. In NICM, scars commonly involved the perivalvular region, with frequent basal septal involvement. During a median follow-up of 819 days, the rates of VA recurrence after multiple procedures and cardiovascular mortality were similar between the groups. The estimated one-year VA-free survival was 64.6 ± 7.0

BACKGROUND AND AIMS:Patients with LMNA gene variants are at high risk for dilated cardiomyopathy and heart failure (HF), but no prediction model for severe HF events exists. This study aimed to describe the incidence of severe HF events and develop a prediction model in a large cohort of patients with adult-onset laminopathies. METHODS:From a population of 660 patients enrolled in the French LMNA nationwide registry, 470 adults were included in the derivation cohort. An independent international validation cohort included 245 additional patients. Baseline characteristics at genetic testing were assessed and the cumulative incidence of the primary endpoint HF-major adverse cardiac events (HF-MACE) was calculated, defined as HF hospitalization, HF-related death, mechanical circulatory support, or heart transplantation. Predictors of HF-MACE were studied after excluding patients with left ventricular ejection fraction (LVEF) <30% at baseline using a Fine-Gray competing risk model, adjusted hazard ratio (aHR) with 95% confidence interval (CI), and Harrell's concordance (C-) index. A secondary composite endpoint, without hospitalization, was also studied. RESULTS:Among 470 patients of the derivation cohort, HF-MACE occurred in 65 over a median follow-up of 7.1 years (interquartile range: 3.4-12.1). Four independent predictors of HF-MACE were identified: male sex (aHR 1.86; 95% CI 1.060-3.290), LVEF <50% (aHR 2.18; 95% CI 1.080-4.400), missense variants in head and rod domains (aHR 2.91; 95% CI 1.110-7.630), and complete left bundle branch block (aHR 2.99; 95% CI 1.400-6.400). The C-index of the model was 0.750 (95% CI 0.720-0.780) in the derivation cohort and 0.758 (95% CI 0.720-0.800) in the validation cohort. The 5-year cumulative incidence of HF-MACE was 1.5% (95% CI 0.6-3.6), 5.0% (95% CI 1.8-8.2), and 22.0% (95% CI 15.6-28.4) among patients with 0, 1, and ≥2 risk factors, respectively. In patients with LVEF <30% at baseline, the 1-year incidence of HF-MACE was 50%, and those patients were excluded from the risk score. CONCLUSIONS:The first prediction model for severe HF events in adult laminopathies was developed, which may facilitate early and optimal preventive management. CLINICAL TRIAL REGISTRATION:URL: https://www.clinicaltrials.gov Unique identifier: NCT03058185.

BACKGROUND:Improved patient outcomes after ventricular arrhythmia (VA) ablation procedure have been found to correlate with procedures being performed in high volume centres. Whether the concentration of expertise in experienced, urban centres disadvantages out-of-area (OOA) patients requires investigation. METHODS:We retrospectively analysed 280 patients undergoing catheter ablation for VAs between 2017 and 2021 at an expert referral centre for VA ablation. In-area (IA) and OOA cases were compared for differences in time from referral to electrophysiologist consultation and ablation procedure. For the subset of patients undergoing catheter ablation for non-premature ventricular complex (PVC) ablation, differences in rates of ventricular tachycardia (VT) recurrence and a composite outcome of VT recurrence, cardiac transplantation or death were also compared. RESULTS:One hundred and eighteen (42.1%) cases during the study period were OOA referrals. The median time from referral to consultation was 0 days (interquartile range [IQR] 0-12), and from referral to ablation was 10 days (IQR 3-87); with no significant difference between IA and OOA patients with regards to timing of ablation (p=0.86 and p=0.32 respectively). IA and OOA patients undergoing non-PVC ablations had similar rates of VT recurrence (34.7% vs. 35.7%, p=0.89) and the composite endpoint (48.3% vs. 44.0%, p=0.55). CONCLUSION:For patients referred to undergo VA ablation at our urban tertiary centre, OOA patients are not disadvantaged compared to IA patients in terms of time to consultation and/or ablation, or long-term outcomes.

Background Cardiac magnetic resonance (CMR) image integration technologies offer promise to guide delineation of ventricular scar and arrhythmogenic substrate; however, there are limited co-registered histological data or comparative studies of commonly used CMR segmentation tools for ventricular tachycardia (VT) ablation. Objectives This study sought to validate 2 commonly used vendor systems (ADAS-3D and inHEART) to integrate CMR late gadolinium enhancement to electroanatomic mapping in catheter ablation of VT. Methods Five sheep underwent anteroseptal infarction with electroanatomic mapping (129 ± 12 days postinfarct). A whole heart histological model of the postinfarction scar was created. CMR was segmented by ADAS-3D and inHEART and validated with histology for 3 layers (the endocardium, intramural layer, and epicardium). A subsequent clinical validation study was performed with 5 human subjects (1 postinfarction VT, 4 nonischemic cardiomyopathy). Critical sites of VT and functional substrate (deceleration zones) were matched to ADAS-3D and inHEART scar. Results CMR-based ADAS-3D and inHEART have comparable accuracy (>75%) with moderate agreement to identify endocardial and intramural scar compared to gold standard whole-heart histology but poorer performance (modest accuracy [60%-68%] and fair agreement in the epicardial layers). Both technologies performed poorly to identify noncompact scar. Critical sites of VT colocalize reliably with ADAS-3D and inHEART scar (88% falling within 1 scar layer). More than 80% of VT critical sites demonstrated CMR late gadolinium enhancement scar in more than 1 layer. Conclusions ADAS-3D and inHEART image integration provide similar characterization of scar distribution and allowed similar display of the anatomic relation of critical re-entry circuit sites detected by mapping to scar. However, limitations exist in the performance of these technologies to identify epicardial and noncompact scar.

Purpose: We report multimodal imaging of intraretinal silicone oil in a case operated for coloboma-associated retinal detachment (RD) and provide imaging based anatomical insights of the route on entry of intraretinal emulsified silicone oil droplets. Method: A 19-year-old male presented with gradual onset diminution of vision in right eye for several years with worsening for 1 month. The patient was evaluated with examination, multimodal imaging, including fundus photography, optical coherence tomography, multicolor imaging, and green reflectance imaging. Result: The right eye showed large inferonasal chorioretinal coloboma sparing the fovea, with dull foveal reflex on color fundus photography, loss of foveal contour with multiple hyperreflective dots predominantly collected in the outer nuclear layer in the foveal region on optical coherence tomography, greenish hue in the foveal region with feather-like projections on multicolor imaging, and crystalline deposits on green reflectance imaging. This was diagnosed as collection of intraretinal silicone oil post-RD surgery in a case of chorioretinal coloboma. Conclusion: We highlight a possible pathway for the intraretinal entry of emulsified silicone oil particles in a case of chorioretinal coloboma.

PURPOSE:To report optical coherence tomography angiography (OCTA) characteristics of bilateral MacTel Type 1 with capillary obliteration. METHODS:Color fundus photography, OCTA, fundus fluorescein angiography, fundus autofluorescence. RESULTS:We describe three cases of bilateral MacTel Type 1 with a special emphasis on OCTA characteristics. CONCLUSION:Optical coherence tomography angiography is a noninvasive method to detect capillary telangiectasia and abnormal vascular tortuosity in the superficial capillary plexus and deep capillary plexus. Optical coherence tomography angiography demonstrates that bilateral MacTel Type 1 may have both aneurysmal and occlusive components.

BACKGROUND:Functional substrate mapping identifies areas of decremental conduction, which are critical targets for ventricular tachycardia (VT) ablation. The evidence for this observation is derived from unblinded studies. OBJECTIVES:In a blinded study, we evaluated the correlation between areas of decremental conduction unveiled with functional substrate mapping and VT critical sites identified using traditional substrate mapping. METHODS:We studied consecutive patients with structural heart disease undergoing VT ablation whereby the operator simultaneously acquired 2 maps: a baseline substrate map (unblinded) simultaneous with a functional substrate map (blinded) using an extra-stimulus pacing protocol. Ablation was performed using conventional mapping techniques without access to functional mapping data. Postprocedure, blinded analyses evaluated the spatial concordance between decremental conduction areas and VT critical sites. RESULTS:Among 33 patients who underwent the extra-stimulus protocol, 20 patients completed mapping and had inducible VT (mean age: 62 [IQR: 54-73] years; 55% ischemic cardiomyopathy [ICM]). Among 51 VTs with putative isthmi or breakthrough sites identified, these sites colocalized with decremental conduction regions in 78% and 73% using 10-milliseconds and 20-milliseconds cutoffs, respectively (P = 0.25). Although colocalization rate did not differ between thresholds, the 20-milliseconds decremental area was smaller (P < 0.01). Colocalization rate was higher in ICM compared with nonischemic cardiomyopathy (NICM) patients (93% vs 59%, P < 0.01 for 10-ms; 86% vs 55%, P = 0.03 for 20-ms). CONCLUSIONS:In a blinded evaluation, areas of decremental conduction identified by functional substrate mapping showed a high degree of colocalization with VT critical sites, particularly in ICM patients. This relationship was less consistent in NICM patients.

BACKGROUND & AIM:Smartwatches can provide a non-invasive heart rate (HR) monitoring to aid screening for atrial fibrillation, however, the accuracy of HR detections in the context of other arrhythmias requires further investigation. We aimed to assess the accuracy of HR measurements of two commonly used wearables at onset, during and termination of various induced and paced arrhythmias. METHOD:Patients undergoing an electrophysiology study were fitted intraprocedurally with both the Apple Watch Series 4 (AW) and Fitbit Versa (FB). Detected HRs on the devices were recorded at initiation, during, and at termination of various paced and induced arrhythmias. True HR was confirmed via intracardiac electrograms and 12-lead electrocardiogram. Detected HRs on the AW and FB were assessed for accuracy, defined as HR with in ±10% of the true rate. RESULTS:A total 322 cardiac rhythms from 32 patients were analysed. Both AW and FB demonstrated reasonable HR detection during sinus rhythm (100% vs 87%; p=0.04) and supraventricular tachycardia (SVT) (89% vs 86%; p=1). Both devices performed poorly at detecting SVT termination (62% vs 41%; p=0.04) and ventricular tachycardia (41% vs 16%; p=0.007). Neither device identified changes in HR during ventricular fibrillation or asystole. CONCLUSIONS:Both the Apple Watch and Fitbit demonstrate reasonable accuracy in HR detection during regular rhythms of supraventricular origin, however, struggle with arrhythmia terminations and ventricular arrhythmias. Care should be taken when assessing HR trends for presence of cardiac arrhythmias.

PURPOSE:To evaluate multimodal imaging of vitelliform lesions in macular telangiectasia type 2. METHOD:Color fundus photograph, optical coherence tomography angiography, fundus autofluorescence, and fundus fluorescein angiography. RESULT:Vitelliform lesions were found in two cases of macular telangiectasia type 2. CONCLUSION:Vitelliform deposits can be present in eyes with macular telangiectasia type 2. Fundus autofluorescence imaging is a highly sensitive modality for detecting vitelliform lesions.

INTRODUCTION:In patients with ischemic cardiomyopathy (ICM), recurrent VF may be treated with catheter ablation by targeting triggering premature ventricular complexes (PVCs) and/or ventricular scar homogenization. Data on optimal ablation strategies in patients with non-ischemic cardiomyopathy (NICM) remain limited. This study aimed to compare ablation strategies and outcomes in patients with recurrent VF due to ICM versus NICM. METHODS AND RESULTS:We retrospectively analyzed consecutive patients with structural heart disease and recurrent VF undergoing catheter ablation. Catheter ablation was performed, including targeting the triggering and/or clinically frequent PVC, targeting any inducible ventricular tachycardia, and/or scar homogenization. Procedural characteristics, arrhythmogenic substrate features, and post-ablation clinical outcomes were compared between ICM and NICM groups. Forty-five patients were included (17 ICM, 28 NICM; mean age 60 ± 15 years; 87% male). PVC ablation was performed in 42% of ICM and 39% of NICM patients, while scar homogenization was undertaken in 76% and 57%, respectively. Left ventricular scar burden, assessed by bipolar and unipolar voltage mapping, was significantly greater in the ICM, whereas the prevalence of abnormal Purkinje potentials was similar between groups. VF-free survival after multiple procedures did not differ between groups, with estimated 1-year rates of 87 ± 9% in ICM and 85 ± 8% in NICM (log-rank p = 0.93). CONCLUSIONS:In patients with NICM and recurrent VF, catheter ablation targeting arrhythmogenic substrate-including unipolar low-voltage regions-combined with PVC ablation yields outcomes comparable to those in ICM, supporting this approach as a reasonable treatment strategy.

BACKGROUND:Very high-power short-duration (vHPSD) radiofrequency ablation (RFA) is an alternative strategy for pulmonary vein isolation. However, rapid temperature rises may cause complications. The QDOT Micro is designed to detect temperature rises for automatic power and irrigation flow adjustments. We compared how differences in ablation electrode design between three RFA catheters impact vHPSD lesions. METHODS:vHPSD RFA was performed within a validated gel tank model. Four-second ablations were delivered with stable contact force using the QDOT, SmartTouch, and TactiFlex SE at 60, 70, 80, and 90 watts, positioned perpendicular (90°), oblique (45°), and parallel (0°) to the ablation target, utilizing 0.9% and 0.45% "half-normal" saline (HNS) irrigation. The SmartTouch and TactiFlex were operated in power-controlled mode, and each configuration was repeated three times, with images captured every second to characterize lesions. RESULTS:In total, 216 vHPSD lesions were delivered. At 90 W, 90°, and 0.9% saline, the QDOT produced lesions with a mean depth of 1.93 mm. The TactiFlex produced shallower lesions, with a mean depth of 1.88 mm (p = 0.02), and the SmartTouch produced the deepest, with a mean depth of 2.37 mm (p < 0.001). The mean diameter of QDOT lesions, at 4.63 mm, was comparable to TactiFlex lesions (4.58 mm, p = 0.8), whilst the SmartTouch lesions were significantly wider than both the QDOT and TactiFlex (6.04 mm, p < 0.001). Steam-pop risk, based on lesion temperature, was lowest for the TactiFlex. CONCLUSION:vHPSD lesions produced with the QDOT achieved greater dimensions and temperatures than those with the TactiFlex under controlled conditions, suggesting a difference in the cooling profile of the ablation electrodes. vHPSD with the SmartTouch or 0.45% HNS are likely to increase the risk of steam pops.