Ranolazine Unveiled: Rediscovering an Old Solution in a New Light.

Ranolazine is an anti-anginal medication that has demonstrated antiarrhythmic properties by inhibiting both late sodium and potassium currents. Studies have shown promising results for ranolazine in treating both atrial fibrillation and ventricular arrhythmias, particularly when used in combination with other medications. This review explores ranolazine's mechanisms of action and its potential role in cardiac arrhythmias treatment in light of previous clinical studies.

Approaching Ventricular Tachycardia Ablation in 2024: An Update on Mapping and Ablation Strategies, Timing, and Future Directions.

This review provides insights into mapping and ablation strategies for VT, offering a comprehensive overview of contemporary approaches and future perspectives in the field. The strengths and limitations of classical mapping strategies, namely activation mapping, pace mapping, entrainment mapping, and substrate mapping, are deeply discussed. The increasing pivotal relevance of CMR and MDCT in substrate definition is highlighted, particularly in defining the border zone, tissue channels, and fat. The integration of CMR and MDCT images with EAM is explored, with a special focus on their role in enhancing effectiveness and procedure safety. The abstract concludes by illustrating the Pisa workflow for the VT ablation procedure.

Feasibility of carbon dioxide insufflation and impact on epicardial approach utilization for ventricular tachycardia ablation in a midvolume referral center.

BACKGROUND: Epicardial access is often crucial for successful ventricular tachycardia (VT) ablation, but it is often burdened by significant procedural risk. Intentional coronary vein exit and intrapericardial CO2 insufflation (EpiCO2) can facilitate subxiphoid pericardial access. OBJECTIVE: This prospective study aimed to assess procedural feasibility, safety, and impact of the introduction of intrapericardial CO2 insufflation for epicardial access in a referral center for VT ablation. METHODS: All consecutive patients treated with epicardial VT ablation between November 2022 and January 2024 with the EpiCO2 technique at Pisa University Hospital were prospectively enrolled and compared in terms of feasibility, efficiency, and safety with a local retrospective cohort of patients treated with subxiphoid dry puncture between July 2018 and October 2022. RESULTS: Twenty-two consecutive patients (90.9% male; mean age, 54.3 years) underwent VT ablation with EpiCO2 during the study period. Epicardial access was achieved in all patients; median time from coronary sinus (CS) cannulation to epicardial access was 33 minutes. Intentional vein exit was successful in all cases, whereas CO2 insufflation was not feasible in 1 patient. There were no major complications and no significant bleeding. Since EpiCO2 introduction, epicardial approach utilization increased from 17.8% to 40% of all VT procedures. Comparison with 20 standard dry approach epicardial ablations showed no significant differences in terms of total procedural duration (322.5 [interquartile range, 296.75-363.75] minutes vs 359 [interquartile range, 323-409] minutes; P = .08). CONCLUSION: In our single-center experience, EpiCO2 was feasible and safe and led to significant increase in procedural volume without affecting total procedural time compared with standard dry puncture.

Arrhythmic risk profile in mitral valve prolapse: A systematic review and metanalysis of 1715 patients.

INTRODUCTION: Mitral valve prolapse (MVP) is a common clinical condition in the general population. A subgroup of patients with MVP may experience ventricular arrhythmias and sudden cardiac death ("arrhythmic mitral valve prolapse" [AMVP]) but how to stratify arrhythmic risk is still unclear. Our meta-analysis aims to identify predictive factors for arrhythmic risk in patients with MVP. METHODS: We systematically searched Medline, Cochrane, Journals@Ovid, Scopus electronic databases for studies published up to December 28, 2022 and comparing AMVP and nonarrhythmic mitral valve prolapse (NAMVP) for what concerns history, electrocardiographic, echocardiographic and cardiac magnetic resonance features. The effect size was estimated using a random-effect model as odds ratio (OR) and mean difference (MD). RESULTS: A total of 10 studies enrolling 1715 patients were included. Late gadolinium enhancement (LGE) (OR: 16.67; p = .005), T-wave inversion (TWI) (OR: 2.63; p < .0001), bileaflet MVP (OR: 1.92; p < .0001) and mitral anulus disjunction (MAD) (OR: 2.60; p < .0001) were more represented among patients with AMVP than in NAMVP. Patients with AMVP were shown to have longer anterior mitral leaflet (AML) (MD: 2.63 mm; p < .0001), posterior mitral leaflet (MD: 2.96 mm; p < .0001), thicker AML (MD: 0.49 mm; p < .0001), longer MAD length (MD: 1.24 mm; p < .0001) and higher amount of LGE (MD: 1.41%; p < .0001) than NAMVP. AMVP showed increased mechanical dispersion (MD: 8.04 ms; 95% confidence interval: 5.13-10.96; p < .0001) compared with NAMVP. CONCLUSIONS: Our meta-analysis proved that LGE, TWI, bileaflet MVP, and MAD are predictive factors for arrhythmic risk in MVP patients.

Transvenous lead extraction: Efficacy and safety of the procedure in female patients.

Background: Existing data on the impact of sex differences on transvenous lead extraction (TLE) outcomes in cardiac device patients are limited. Objective: The purpose of this study was to evaluate the safety and efficacy of mechanical TLE in female patients. Methods: A retrospective evaluation was performed on 3051 TLE patients (group 1: female; group 2: male) from a single tertiary referral center. All individuals received treatment using single sheath mechanical dilation and various venous approaches as required. Results: Our analysis included 3051 patients (group 1: 750; group 2: 2301), with a total of 5515 leads handled with removal. Female patients were younger, had a higher left ventricular ejection fraction, and lower prevalences of coronary artery disease and diabetes mellitus. Infection was more common in male patients, whereas lead malfunction or abandonment were more frequent in female patients. Radiologic success was lower in female patients (95.8% vs 97.5%; P = .003), but there was no significant difference in clinical success between groups (97.2% vs 97.5%; P = .872). However, major complications (1.33% vs 0.60%; P <.001) and procedural mortality (0.4% vs 0.1%; P <.001) were higher in females compared to male patients. After multivariate analysis, female sex emerged as the only predictor of major complications, including deaths (odds ratio 3.96; 95% confidence interval 1.39-11.24). Conclusion: TLE using unpowered simple mechanical sheaths in female patients is safe and effective, but is associated with lower radiologic success and higher complication rates and mortality than in males. This finding underscores the importance of recognizing sex differences in TLE outcomes.

Short and Long-Term Outcomes of Lesion Index-Guided High-Power Short-Duration Approach for Atrial Fibrillation Ablation.

High-power short-duration (HPSD) ablation is an increasingly used ablation strategy for pulmonary vein isolation (PVI) procedures, but Lesion Index (LSI)-guided HPSD radiofrequency (RF) applications have not been described in this clinical setting. We evaluated the procedural efficiency and safety of an LSI-guided HPSD strategy for atrial fibrillation (AF) ablation. Paroxysmal and persistent AF patients scheduled for AF ablation were prospectively enrolled and divided into two groups, according to the ablation power used (≥45 W for the LSI-HP Group and ≤40 W for the LSI-LP group). All patients underwent only PVI LSI-guided ablation (5.5 to 6 anteriorly; 5 to 5.5 superiorly, 4.5 to 5 posteriorly) with a point-by-point strategy and an inter-lesion distance <6 mm. Forty-six patients with AF (25 in the LSI-HP Group vs 21 in the LSI-LP Group)-59% paroxysmal, 78% male, with low-intermediate CHA2DS2-Vasc scores (2 [1-3]), a preserved ejection fraction (65 ± 6%) and a mean left atrial index volume of 39 ± 13 mL/m2 were prospectively enrolled. Baseline clinical characteristics were comparable between groups. PVI was successful in all patients. The RF time (29 (23-37) vs. 49 (41-53) min, p < 0.001), total procedure time (131 (126-145) vs. 155 (139-203) min, p = 0.007) and fluoroscopy time (12 (10-18) vs. 21 (16-26) min, p = 0.001) were significantly lower in the LSI-HP Group. No complications or steam pops were seen in either group. LSI-HP AF ablation significantly improved procedural efficiency-reducing ablation time, total procedural duration, and fluoroscopy use, while maintaining a comparable safety profile to lower-power procedures.

Feasibility and Accuracy of Noninvasive Continuous Arterial Pressure Monitoring during Transcatheter Atrial Fibrillation Ablation.

INTRODUCTION: Transcatheter atrial fibrillation (AF) ablation is still carried out with continuous invasive radial arterial blood pressure (IBP) monitoring in many centers. Continuous noninvasive blood pressure (CNBP) measurement using the volume-clamp method is a noninvasive alternative method used in ICU. No data on CNBP reliability are available in the electrophysiology lab during AF ablation, where rhythm variations are common. BACKGROUND: The objective of the present study was to compare continuous noninvasive arterial pressure measured with the ClearSight device (Edwards Lifesciences, Irvine, CA, USA) with invasive radial artery pressure used as the reference method during AF ablation. METHODS: We prospectively enrolled 55 consecutive patients (age 62 ± 11 years, 80% male) undergoing transcatheter AF ablation (62% paroxysmal, 38% persistent) at our center. Standard of care IBP monitoring via a radial cannula and a contralateral noninvasive finger volume-clamp CNBP measurement device were positioned simultaneously in all patients for the entire procedure. Bland-Altman analysis was used to analyze the agreement between the two techniques. RESULTS: A total of 1219 paired measurements for systolic, diastolic, and mean arterial pressure were obtained in 55 subjects, with a mean (SD) of 22 (9) measurements per patient. The mean bias (SD) was -12.97 (13.89) mmHg for systolic pressure (level of agreement -14.24-40.20; correlation coefficient 0.84), -1.85 (8.52) mmHg for diastolic pressure (level of agreement -18.54-14.84; correlation coefficient 0.77) and 2.31 (8.75) mmHg for mean pressure (level of agreement -14.84-19.46; correlation coefficient 0.85). CONCLUSION: In patients undergoing AF ablation, CNBP monitoring with the ClearSight device showed acceptable agreement with IBP monitoring. Larger studies are needed to confirm the potential clinical implications of continuous noninvasive BP monitoring during AF ablation.

Non-continuous mobile electrocardiogram monitoring for post-transcatheter aortic valve replacement delayed conduction disorders put to the test.

AIMS: Permanent pacemaker implantation (PPM-I) remains nowadays the most important drawback of transcatheter aortic valve replacement (TAVR) procedure and the optimal strategy of delayed conduction disturbances (CDs) in these patients is unclear. The study aimed to validate an ambulatory electrocardiogram (ECG) monitoring through a 30 s spot ambulatory digital mobile ECG (AeECG), by using KardiaMobile-6L device in a 30-day period after TAVR procedure. METHODS AND RESULTS: Between March 2021 and February 2022, we consecutively enrolled all patients undergoing TAVR procedure, except pacemaker (PM) carriers. At discharge, all patients were provided of a KardiaMobile-6L device and a spot digital ECG (eECG) recording 1 month schedule. Clinical and follow-up data were collected, and eECG schedule compliance and recording quality were explored. Among 151 patients without pre-existing PM, 23 were excluded for pre-discharge PPM-I, 18 failed the KardiaMobile-6L training phase, and 10 refused the device. Delayed CDs with a Class I/IIa indication for PPM-I occurred in eight patients (median 6 days). Delayed PPM-I vs. non-delayed PPM-I patients were more likely to have longer PR and QRS intervals at discharge. PR interval at discharge was the only independent predictor for delayed PPM-I at multivariate analysis. The overall eECG schedule compliance was 96.5%. None clinical adverse events CDs related were documented using this new AeECG monitoring modality. CONCLUSION: A strategy of 30 s spot AeECG is safe and efficacious in delayed CDs monitoring after TAVR procedure with a very high eECG schedule level of compliance.

Dark papillary muscles sign: a novel prognostic marker for cardiac magnetic resonance.

OBJECTIVES: The prognostic role of left ventricular (LV) papillary muscle abnormalities in patients with preserved LV systolic ejection fraction (LVEF) is unknown. We sought to evaluate the prognosis role of LV papillary muscle abnormalities by CMR in patients with ventricular arrhythmias, preserved LVEF with no cardiac disease. METHODS: A total of 391 patients with > 500/24 h premature ventricular complexes and/or with non-sustained ventricular tachycardia (NSVT), preserved LVEF, and no cardiac disease were enrolled. Different features of LV papillary muscles were considered: supernumerary muscles, papillary thickness, the attachment, late gadolinium enhancement (LGE). Dark-Paps was defined as end-systolic signal hypointensity of both papillary muscles in early post-contrast cine CMR images. Mitral valve prolapse, mitral annular disjunction (MAD), and myocardial LGE were considered. RESULTS: Dark-Paps was found in 79 (20%) patients and was more frequent in females. It was associated with higher prevalence of mitral valve prolapse and MAD. During a median follow-up of 2534 days, 22 hard cardiac events occurred. At Kaplan-Meier curve analysis, patients with Dark-Paps were at higher risk of events than those without (p < 0.0001). Dark-Paps was significantly associated with hard cardiac events in all the multivariate models. Dark-Paps improved prognostic estimation when added to NSVT (p = 0.0006), to LGE (p = 0.005) and to a model including NSVT+LGE (p = 0.014). Dark-Paps allowed a significant net reclassification when added to NSVT (NRI 0.30, p = 0.03), to LGE (NRI 0.25, p = 0.04), and to NSVT + LGE (NRI 0.32, p  = 0.02). CONCLUSIONS: In LV papillary muscles, Dark-Paps is a novel prognostic marker in patients with ventricular arrhythmias and preserved ejection fraction. KEY POINTS: • Papillary muscle abnormalities are seen in patients with ventricular arrhythmias and preserved left ventricular ejection fraction. • Early post-contrast hypointensity of papillary muscles in end-systolic cine images (Dark-Paps) is a novel prognostic marker in patients with ventricular arrhythmias and preserved ejection fraction. • Dark-Paps had an additive prognostic role over late gadolinium enhancement and non-sustained ventricular tachycardia.

His-bundle pacing to treat an unusual case of chest pain after pacemaker implant.

A 63-year-old man with hypertension and 3-vessel coronary artery disease previously treated with coronary artery bypass graft was admitted to our emergency room complaining of chest pain. He had undergone pacemaker implant 5 months before due to paroxysmal advanced atrioventricular block. Electrocardiography and troponin testing were unremarkable. Echocardiography and chest X-ray ruled out lead displacement and perforation. Interrogation showed normal parameters [right atrium: impedance 550 Ohm bipolar, sensing 2.4 mV bipolar; threshold 0.50 V/0.4 ms bipolar; right ventricle (RV): impedance 580 Ohm bipolar, sensing > 25 mV bipolar; threshold 1.5 V/0.4 ms bipolar and 0.4 V/0.4 ms unipolar]. Pain was evoked only during RV pacing. An electrophysiology study demonstrated painful RV pacing from multiple sites. We hypothesized that pain was associated with pacing-induced dyssynchrony. His-bundle pacing (HBP) was considered as a solution. We achieved HBP with a bipolar fixed-screw catheter connected to a cardiac resynchronization therapy pacemaker generator. During HBP above threshold (4.00 V/1.00 ms) the patient did not complain of any pain. He was discharged 3 days later pain-free with His-bundle lead amplitude set at 5.00 V/1.00 ms. After 6 months the patient was asymptomatic, with the device showing normal functioning. This is the first clinical experience of painful RV pacing treated with HBP. .

Ventricular tachycardia ablation guided or aided by scar characterization with cardiac magnetic resonance: rationale and design of VOYAGE study.

BACKGROUND: Radiofrequency ablation has been shown to be a safe and effective treatment for scar-related ventricular arrhythmias (VA). Recent preliminary studies have shown that real time integration of late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) images with electroanatomical map (EAM) data may lead to increased procedure efficacy, efficiency, and safety. METHODS: VOYAGE is a prospective, randomized, multicenter controlled open label study designed to compare in terms of efficacy, efficiency, and safety a CMR aided/guided workflow to standard EAM-guided ventricular tachycardia (VT) ablation. Patients with an ICD or with ICD implantation expected within 1 month, with scar related VT, suitable for CMR and multidetector computed tomography (MDCT) will be randomized to a CMR-guided or CMR-aided approach, whereas subjects unsuitable for imaging or with image quality deemed not sufficient for postprocessing will be allocated to standard of care ablation. Primary endpoint is defined as VT recurrences (sustained or requiring appropriate ICD intervention) during 12 months follow-up, excluding the first month of blanking period. Secondary endpoints will include procedural efficiency, safety, impact on quality of life and comparison between CMR-guided and CMR-aided approaches. Patients will be evaluated at 1, 6 and 12 months. DISCUSSION: The clinical impact of real time CMR-guided/aided ablation approaches has not been thoroughly assessed yet. This study aims at defining whether such workflow results in more effective, efficient, and safer procedures. If proven to be of benefit, results from this study could be applied in large scale interventional practice. Trial registrationClinicalTrials.gov, NCT04694079, registered on January 1, 2021.

Left atrial thrombus and smoke resolution in patients with atrial fibrillation under chronic oral anticoagulation.

BACKGROUND: The study aimed to explore the resolution of left atrial and left atrial appendage (LAA) spontaneous echo-contrast or thrombus in patients with nonvalvular atrial fibrillation/flutter (AF/AFL) under chronic oral anticoagulation (OAC). METHODS: A single-center retrospective analysis of patients who underwent a transesophageal echocardiography (TOE) for an electrical cardioversion was conducted. RESULTS: Among 277 TOE performed, 73 cases (26%) of LAA echo-contrast or thrombus were detected, 53 patients with LAA/LA echo-contrast (19%) and 20 (7%) with a thrombus. All patients were under chronic anticoagulation with a VKA (65%) or with a NOAC (35%). The Echo-contrast Group maintained the same OAC strategy in 49 patients (93%). The Thrombus Group kept the same OAC strategy with a NOAC in 6 cases (30%) and changed the strategy in 14 patients (70%), titrating NOAC dose in 1 (5%) and the VKA dose in 4 (20%) and switching from NOAC to VKA in 5 (25%), from VKA to NOAC in 3 (15%), and from NOAC to NOAC in 1 (5%). Smoke resolution was observed in 4/40 cases (10%) of the smoke group and thrombus resolution in 8/15 (53%) of the thrombus group. Patients with thrombus resolution had a lower CHA2DS2-Vasc score (3.5 ± 2 vs 4 ± 1, p = 0.05), were more often under NOAC (37.5 vs 28%, p = 0.07), and had a longer anticoagulation time (7.5 vs 4 months, p = 0.08). CONCLUSION (S): Changing OAC strategy is associated with thrombus resolution in more than 50% of chronically anticoagulated patients.

Clinical impact of high-density mapping on the acute and long term outcome of atypical atrial flutter ablations.

PURPOSE: We evaluated the clinical impact of the high-density (HD) mapping compared with the standard low-density (LD) ablation catheter mapping technique in the treatment of AFLs. METHODS: We retrospectively evaluated short and long outcomes of patients approached with an HD and a LD electro-anatomical strategy for atypical AFLs. RESULTS: Eighty-seven patients were included. Patients were almost male (60%), relatively old (65 ± 8 years), with a moderate CHA2DS2Vasc score (2.3 ± 1.3), a preserved ejection fraction (58 ± 6), and moderate atrial dilatation (44 ± 7 mm). Baseline clinical characteristics were comparable between groups (p = NS). Among AFLs, 10 (11%) were located in the right and 78 (89%) in the left atrium, including 22 (28%) roof dependent and 37 (47%) mitral dependent (p = NS). Sinus rhythm restoration during ablation was more frequently observed in the HD group (79% vs 56%, p = 0.037), without differences in mapping time, procedural time, and radiological dose (p = NS). Overall AFL/AT/AF recurrence rate at 1, 2, and 3 years was lower in the HD group (14% vs 37% p = 0.02, 14% vs 48% p = 0.002 and 14% vs 50% p < 0.001, respectively) with a time-dependent trend only in the LD group (37% vs 48% vs 50% at 1, 2, and 3 years respectively, p = 0.059). HD mapping (OR 0.17; 95% CI 0.04-0.66) and younger age (OR 1.09; 95% CI 1.01-1.19) resulted independent predictors of overall arrhythmias at follow-up. CONCLUSIONS: Short- and long-term outcomes of atypical AFL ablation were better in the case of HD mapping, which resulted independent predictor of arrhythmia recurrences.

Standard versus strict stability criteria in radiofrequency paroxysmal atrial fibrillation ablation using ablation index.

PURPOSE: To compare the outcome of paroxysmal atrial fibrillation (AF) ablation via pulmonary vein isolation using Ablation Index (AI) with strict or standard stability criteria. METHODS: We enrolled 130 consecutive naive patients affected by paroxysmal AF who underwent PVI at two high-volume centers. AI target was ≥380 at the posterior wall and ≥500 at the anterior wall. Strict versus standard stability criteria were set for Group 1 (65 patients) and Group 2 (65 patients), respectively. We compared those strategies with a historical cohort of 72 consecutive patients treated at same centers in the VISITALY study, using average force ≥10 g and strict stability criteria as target parameters. Interlesion distance target was <6 mm. Recurrence was defined as any AF, atrial tachycardia (AT) or atrial flutter (AFL) during the 12 months after ablation, excluding a 90-days blanking period. RESULTS: Procedure duration (224.05 ± 47.21 vs. 175.61 ± 51.29 min; p < .001), fluoroscopy time (11.85 ± 4.38 vs. 10.46 ± 6.49 min; p = .019) and pericardial effusion rate (9.23% vs. 0%; p = .01) were higher in Group 1 than in Group 2. Freedom from AF/AT/AFL at 12 months was not significantly different (Group 1: 86.15%; Group 2: 90.77%; p = .42). Compared to VISITALY study, there were not significant differences in terms of recurrences. CONCLUSION: A strategy of PVI using AI with standard stability criteria performed the best in terms of procedure efficiency and safety. Twelve-months arrhythmia-free survival rate was comparable with other strategies pursuing an interlesion distance target <6 mm, regardless of the use of AI.

Multimodality Imaging for Atrial Fibrosis Detection in the Era of Precision Medicine.

In recent years, atrial fibrillation (AF) has increasingly become a focus of attention because it represents the most encountered arrhythmia in clinical practice and a major cause of morbidity and mortality. Issues underlying AF have long been debated; nevertheless, electrical, contractile, and structural remodeling is demonstrated to be the pivotal contributor to arrhythmic substrate. Fibrosis is a hallmark of arrhythmogenic structural remodeling, resulting from an accumulation of fibrillar collagen deposits, as a reparative process to replace degenerating myocardium with concomitant reactive fibrosis, which causes interstitial expansion. Although the precise role of fibrosis in AF initiation and maintenance remains to be fully elucidated, a better definition of its extent and distribution may assist in designing individually tailored ablation approaches and improving procedure outcomes by targeting the fibrotic substrates with an organized strategy employing imaging resources. A deep comprehension of the mechanisms underlying atrial fibrosis could be crucial to setting up improved strategies for preventing AF-promoting structural remodeling. Imaging modalities such as echocardiography, cardiac computed tomography, and cardiac magnetic resonance, combined sometimes with invasive electroanatomical mapping, could provide valuable information for the optimal patients' management if their use is not limited to cardiac anatomy study but extended to characterize abnormal left atrial substrate. Although pulmonary vein isolation is usually efficacious in treating paroxysmal AF, it is not sufficient for many patients with nonparoxysmal arrhythmias, particularly those with longstanding persistent AF. Noninvasive imaging techniques play a pivotal role in the planning of arrhythmic substrates ablation and show a strong correlation with electro-anatomic mapping, whose novel multipolar mapping catheters allow nowadays a more precise comprehension of atrial substrate. This review aims to explore the impact of the various imaging modalities for the detection of atrial fibrosis and their role in the management of AF.