Arrhythmic Risk Stratification in Cardiac Amyloidosis: A Review of the Current Literature.

Cardiac amyloidosis is the most frequent infiltrative disease caused by the deposition of misfolded proteins in the cardiac tissue, leading to heart failure, brady- and tachyarrhythmia and death. Conduction disorders, atrial fibrillation (AF) and ventricular arrhythmia (VA) significantly impact patient outcomes and demand recognition. However, several issues remain unresolved regarding early diagnosis and optimal management. Extreme bradycardia is the most common cause of arrhythmic death, while fast and sustained VAs can be found even in the early phases of the disease. Risk stratification and the prevention of sudden cardiac death are therefore to be considered in these patients, although the time for defibrillator implantation is still a subject of debate. Moreover, atrial impairment due to amyloid fibrils is associated with an increased risk of AF resistant to antiarrhythmic therapy, as well as recurrent thromboembolic events despite adequate anticoagulation. In the last few years, the aging of the population and progressive improvements in imaging methods have led to increases in the diagnosis of cardiac amyloidosis. Novel therapies have been developed to improve patients' functional status, quality of life and mortality, without data regarding their effect on arrhythmia prevention. In this review, we consider the latest evidence regarding the arrhythmic risk stratification of cardiac amyloidosis, as well as the available therapeutic strategies.

Exploring suitability to electrical storm ablation in patients in waiting list for heart transplantation: A single center experience.

Electrical storm (ES) is among the most fearsome events in patients in waiting list for heart transplantation (HT) and catheter ablation (CA) demonstrated to be effective in reduce the arrhythmic burden. However, selection criteria for CA suitability in this specific population have never been addressed before. We retrospectively enrolled 36 patients (mean age 51 ± 8 years; 83% men) waiting HT referred to our department for ES resistant to antiarrhythmic drugs and percutaneous stellate ganglion blockade. Twenty patients were judged suitable for VT ablation according to specific criteria including absence of increased arrhythmic burden secondary to volume overload and hemodynamic decompensation; expected CA outcome favorable due to etiology of the cardiomyopathy, no need for coronary revascularization and technical feasibility of the procedure. The pre-emptive use of mechanical circulatory supports (MCS) were discussed integrating the PAINESD score with additional clinical and hemodynamic parameters. Acute procedural success was accounted in 85% of cases with only two major complications. The CA group reported lower length of in-hospital stay after CA suitability evaluation (56 ± 17 vs. 131 ± 64 days, p = .004). Furthermore, at a mean follow-up of 703 ± 145 days, this group showed reduction of ventricular arrhythmia (VA) recurrence leading to implantable cardioverter defibrillator shock (4 vs. 8, p = .051) and underwent HT with a lower level of urgency (0 vs. 6 patients needed for UNOS1 status upgrade). Respectively, one patient of the CA group and two patients of the conservative group died (p = .839). At the end of follow-up, eight patients underwent heart transplantation (p = .964) while four patients underwent Left Ventricular Assist device (LVAD) implantation (p = .440). This pilot study should be a proof for further studies exploring CA of VAs as a possible bridge therapy to HT.

Contemporary Advances in Cardiac Remote Monitoring: A Comprehensive, Updated Mini-Review.

Over the past decade, remote monitoring (RM) has become an increasingly popular way to improve healthcare and health outcomes. Modern cardiac implantable electronic devices (CIEDs) are capable of recording an increasing amount of data related to CIED function, arrhythmias, physiological status and hemodynamic parameters, providing in-depth and updated information on patient cardiovascular function. The extensive use of RM for patients with CIED allows for early diagnosis and rapid assessment of relevant issues, both clinical and technical, as well as replacing outpatient follow-up improving overall management without compromise safety. This approach is recommended by current guidelines for all eligible patients affected by different chronic cardiac conditions including either brady- and tachy-arrhythmias and heart failure. Beyond to clinical advantages, RM has demonstrated cost-effectiveness and is associated with elevated levels of patient satisfaction. Future perspectives include improving security, interoperability and diagnostic power as well as to engage patients with digital health technology. This review aims to update existing data concerning clinical outcomes in patients managed with RM in the wide spectrum of cardiac arrhythmias and Hear Failure (HF), disclosing also about safety, effectiveness, patient satisfaction and cost-saving.

Atrial tachycardia ablation through the sub-pulmonary ventricle in a patient with multiple malformations associated with congenitally corrected transposition of the great arteries and double-sided slow-pathway.

A 46-year-old woman with congenitally corrected transposition of the great arteries (ccTGA) associated with dextrocardia, situs viscerus inversus, and left superior vena cava persistence presented with an incessant supraventricular tachycardia. Electrophysiological study was not conclusive in differential diagnosis of atrial tachycardia versus atypical atrioventricular (AV) nodal reentrant tachycardia, also due to the unconventional anatomy of the coronary sinus. By a comprehensive mapping of cardiac chambers, a double side slow-pathway was localized in both atrial chambers and subsequently ablated by radiofrequency delivery without tachycardia changes. Aortic root and cusps were devoid of electrical activity. The muscular part of the sub-pulmonary ventricle at the level of interatrial septum showed an earliest activation signal of -90 ms and ablation of this site was effective in abolish the tachycardia. This is the first case to report technical concerns of septal atrial tachycardia ablation in ccTGA associated with multiple anatomical malformations. Moreover, some peculiarities have been reported for the first time including the presence of double-side AV nodal slow-pathway and atypical localization of the tachycardia origin into the muscular part of the sub-pulmonary ventricle instead of posterior pulmonary cusp.

Left bundle branch area versus conventional pacing after transcatheter valve implant for aortic stenosis: the LATVIA study.

BACKGROUND: Atrioventricular block (AVB) is a frequent complication in patients undergoing transcatheter aortic valve implantation (TAVI). Right apex ventricular pacing (RVP) represents the standard treatment but may induce cardiomyopathy over the long term. Left bundle branch area pacing (LBBAP) is a promising alternative, minimizing the risk of desynchrony. However, available evidence with LBBAP after TAVI is still low. OBJECTIVE: To assess the feasibility and safety of LBBAP for AVB post-TAVI compared with RVP. METHODS: Consecutive patients developing AVB early after TAVI were enrolled between 1 January 2022 and 31 December 2022 at three high-volume hospitals and received LBBAP or RVP. Data on procedure and at short-term follow-up (at least 3 months) were collected. RESULTS: A total of 38 patients (61% men, mean age 83 ±â€Š6 years) were included; 20 patients (53%) received LBBAP. Procedural success was obtained in all patients according to chosen pacing strategy. Electrical pacing performance at implant and after a mean follow-up of 4.2 ±â€Š2.8 months was clinically equivalent for both pacing modalities. In the LBBAP group, procedural time was longer (70 ±â€Š17 versus 58 ±â€Š15 min in the RVP group, P  = 0.02) and paced QRS was shorter (120 ±â€Š19 versus 155 ±â€Š12 ms at implant, P  < 0.001; 119 ±â€Š18 versus 157 ±â€Š9 ms at follow-up, P  < 0.001). Complication rates did not differ between the two groups. CONCLUSION: In patients with AVB after TAVI, LBBAP is feasible and safe, resulting in a narrow QRS duration, either acutely and during the follow-up, compared with RVP. Further studies are needed to evaluate if LBBAP reduces pacing-induced cardiomyopathy in this clinical setting.

Device-detected atrial sensing amplitudes as a marker of increased risk for new onset and progression of atrial high-rate episodes.

BACKGROUND: Atrial high-rate episodes (AHREs) are frequent in patients with cardiac implantable electronic devices. A decrease in device-detected P-wave amplitude may be an indicator of periods of increased risk of AHRE. OBJECTIVE: The objective of this study was to assess the association between P-wave amplitude and AHRE incidence. METHODS: Remote monitoring data from 2579 patients with no history of atrial fibrillation (23% pacemakers and 77% implantable cardioverter-defibrillators, of which 40% provided cardiac resynchronization therapy) were used to calculate the mean P-wave amplitude during 1 month after implantation. The association with AHRE incidence according to 4 strata of daily burden duration (≥15 minutes, ≥6 hours, ≥24 hours, ≥7 days) was investigated by adjusting the hazard ratio with the CHA2DS2-VASc score. RESULTS: The adjusted hazard ratio for 1-mV lower mean P-wave amplitude during the first month increased from 1.10 (95% confidence interval [CI], 1.05-1.15; P < .001) to 1.18 (CI, 1.09-1.28; P < .001) with AHRE duration strata from ≥15 minutes to ≥7 days independent of the CHA2DS2-VASc score. Of 871 patients with AHREs, those with 1-month P-wave amplitude <2.45 mV had an adjusted hazard ratio of 1.51 (CI, 1.19-1.91; P = .001) for progression of AHREs from ≥15 minutes to ≥7 days compared with those with 1-month P-wave amplitude ≥2.45 mV. Device-detected P-wave amplitudes decreased linearly during the 1 year before the first AHRE by 7.3% (CI, 5.1%-9.5%; P < .001 vs patients without AHRE). CONCLUSION: Device-detected P-wave amplitudes <2.45 mV were associated with an increased risk of AHRE onset and progression to persistent forms of AHRE independent of the patient's risk profile.

Real-world data of patients affected by advanced heart failure treated with implantable cardioverter defibrillator and left ventricular assist device: Results of a multicenter observational study.

BACKGROUND: Left ventricular assist device (L-VAD) implantation is increasingly used in patients with heart failure (HF) and most patients also have an implantable cardioverter defibrillator (ICD). Limited data are available on the incidence of ICD therapies and complications in this special setting. The aim of this study was to analyze the real-world incidence and predictors of ICD therapies, complications and interactions between ICD and L-VAD. METHODS: We conducted a multicenter retrospective observational study in patients with advanced HF implanted with ICD and a continuous-flow L-VAD, followed-up in five advanced HF centers in Northern Italy. RESULTS: A total of 234 patients (89.7% male, median age 59, 48.3% with ischemic etiology) were enrolled. After a median follow-up of 21 months, 66 patients (28.2%) experienced an appropriate ICD therapy, 22 patients (9.4%) an inappropriate ICD therapy, and 17 patients (7.3%) suffered from an interaction between ICD and L-VAD. The composite outcome of all ICD-related complications was reported in 41 patients (17.5%), and 121 (51.7%) experienced an L-VAD-related complication. At multivariable analysis, an active ventricular tachycardia (VT) zone and a prior ICD generator replacement were independent predictors of ICD therapies and of total ICD-related complications, respectively. CONCLUSIONS: Real-world patients with both L-VAD and ICD experience a high rate of ICD therapies and complications. Our findings suggest the importance of tailoring device programming in order to minimize the incidence of unnecessary ICD therapies, thus sparing the need for ICD generator replacement, a procedure associated to a high risk of complications.

Arrhythmogenic Cardiomyopathy: Definition, Classification and Arrhythmic Risk Stratification.

Arrhythmogenic cardiomyopathy (ACM) is a heart disease characterized by a fibrotic replacement of myocardial tissue and a consequent predisposition to ventricular arrhythmic events, especially in the young. Post-mortem studies and the subsequent diffusion of cardiac MRI have shown that left ventricular involvement in arrhythmogenic cardiomyopathy is common and often develops early. Regarding the arrhythmic risk stratification, the current scores underestimate the arrhythmic risk of patients with arrhythmogenic cardiomyopathy with left involvement. Indeed, the data on arrhythmic risk stratification in this group of patients are contradictory and not exhaustive, with the consequence of not correctly identifying patients at a high arrhythmic risk who deserve protection from arrhythmic death. We propose a literature review on arrhythmic risk stratification in patients with ACM and left involvement to identify the main features associated with an increased arrhythmic risk in this group of patients.

The Fluoroless Future in Electrophysiology: A State-of-the-Art Review.

Fluoroscopy has always been the cornerstone imaging method of interventional cardiology procedures. However, radiation exposure is linked to an increased risk of malignancies and multiorgan diseases. The medical team is even more exposed to X-rays, and a higher incidence of malignancies was reported in this professional group. In the last years, X-ray exposure has increased rapidly, involving, above all, the medical team and young patients and forcing alternative fluoroless imaging methods. In cardiac electrophysiology (EP) and pacing, the advent of 3D electroanatomic mapping systems with dedicated catheters has allowed real-time, high-density reconstruction of both heart anatomy and electrical activity, significantly reducing the use of fluoroscopy. In addition, the diffusion of intracardiac echocardiography has provided high anatomical resolution of moving cardiac structures, providing intraprocedural guidance for more complex catheter ablation procedures. These methods have largely demonstrated safety and effectiveness, allowing for a dramatic reduction in X-ray delivery in most arrhythmias' ablations. However, some technical concerns, as well as higher costs, currently do not allow their spread out in EP labs and limit their use to only procedures that are considered highly complex and time-consuming and in young patients. In this review, we aim to update the current employment of fluoroless imaging in different EP procedures, focusing on its strengths and weaknesses.

Fighting Cardiac Thromboembolism during Transcatheter Procedures: An Update on the Use of Cerebral Protection Devices in Cath Labs and EP Labs.

Intraprocedural stroke is a well-documented and feared potential risk of cardiovascular transcatheter procedures (TPs). Moreover, subclinical neurological events or covert central nervous system infarctions are concerns related to the development of dementia, future stroke, cognitive decline, and increased risk of mortality. Cerebral protection devices (CPDs) were developed to mitigate the risk of cardioembolic embolism during TPs. They are mechanical barriers designed to cover the ostium of the supra-aortic branches in the aortic arch, but newer devices are able to protect the descending aorta. CPDs have been mainly designed and tested to provide cerebral protection during transcatheter aortic valve replacement (TAVR), but their use in both Catheterization and Electrophysiology laboratories is rapidly increasing. CPDs have allowed us to perform procedures that were previously contraindicated due to high thromboembolic risk, such as in cases of intracardiac thrombosis identified at preprocedural assessment. However, several concerns related to their employment have to be defined. The selection of patients at high risk of thromboembolism is still a subjective choice of each center. The aim of this review is to update the evidence on the use of CPDs in either Cath labs or EP labs, providing an overview of their structural characteristics. Future perspectives focusing on their possible future employment are also discussed.

Subcutaneous Implantable Cardioverter Defibrillator: A Contemporary Overview.

The difference between subcutaneous implantable cardioverter defibrillators (S-ICDs) and transvenous ICDs (TV-ICDs) concerns a whole extra thoracic implantation, including a defibrillator coil and pulse generator, without endovascular components. The improved safety profile has allowed the S-ICD to be rapidly taken up, especially among younger patients. Reports of its role in different cardiac diseases at high risk of SCD such as hypertrophic and arrhythmic cardiomyopathies, as well as channelopathies, is increasing. S-ICDs show comparable efficacy, reliability, and safety outcomes compared to TV-ICD. However, some technical issues (i.e., the inability to perform anti-bradycardia pacing) strongly limit the employment of S-ICDs. Therefore, it still remains only an alternative to the traditional ICD thus far. This review aims to provide a contemporary overview of the role of S-ICDs compared to TV-ICDs in clinical practice, including technical aspects regarding device manufacture and implantation techniques. Newer outlooks and future perspectives of S-ICDs are also brought up to date.

Electrocardiogram Changes in the Postictal Phase of Epileptic Seizure: Results from a Prospective Study.

BACKGROUND: The brain and heart are strictly linked and the electrical physiologies of these organs share common pathways and genes. Epilepsy patients have a higher prevalence of electrocardiogram (ECG) abnormalities compared to healthy people. Furthermore, the relationship between epilepsy, genetic arrhythmic diseases and sudden death is well known. The association between epilepsy and myocardial channelopathies, although already proposed, has not yet been fully demonstrated. The aim of this prospective observational study is to assess the role of the ECG after a seizure. MATERIALS AND METHODS: From September 2018 to August 2019, all patients admitted to the emergency department of San Raffaele Hospital with a seizure were enrolled in the study; for each patient, neurological, cardiological and ECG data were collected. The ECG was performed at the time of the admission (post-ictal ECG) and 48 h later (basal ECG) and analyzed by two blinded expert cardiologists looking for abnormalities known to indicate channelopathies or arrhythmic cardiomyopathies. In all patients with abnormal post-ictal ECG, next generation sequencing (NGS) analysis was performed. RESULTS: One hundred and seventeen patients were enrolled (females: 45, median age: 48 ± 12 years). There were 52 abnormal post-ictal ECGs and 28 abnormal basal ECGs. All patients with an abnormal basal ECG also had an abnormal post-ictal ECG. In abnormal post-ictal ECG, a Brugada ECG pattern (BEP) was found in eight patients (of which two had BEP type I) and confirmed in two basal ECGs (of which zero had BEP type I). An abnormal QTc interval was identified in 20 patients (17%), an early repolarization pattern was found in 4 patients (3%) and right precordial abnormalities were found in 5 patients (4%). Any kind modification of post-ictal ECG was significantly more pronounced in comparison with an ECG recorded far from the seizure (p = 0.003). A 10:1 higher prevalence of a BEP of any type (particularly in post-ictal ECG, p = 0.04) was found in our population compared to general population. In three patients with post-ictal ECG alterations diagnostic for myocardial channelopathy (BrS and ERP), not confirmed at basal ECG, a pathogenic gene variant was identified (KCNJ8, PKP2 and TRMP4). CONCLUSION: The 12-lead ECG after an epileptic seizure may show disease-related alterations otherwise concealed in a population at a higher incidence of sudden death and channelopathies. Post-ictal BEP incidence was higher in cases of nocturnal seizure.

Prognostic significance of remotely monitored nocturnal heart rate in heart failure patients with reduced ejection fraction.

BACKGROUND: Elevated resting heart rate is a risk factor for cardiovascular events. OBJECTIVE: The purpose of this study was to investigate the clinical significance of nocturnal heart rate (nHR) and 24-hour mean heart rate (24h-HR) obtained by continuous remote monitoring (RM) of implantable devices. METHODS: We analyzed daily-sampled trends of nHR, 24h-HR, and physical activity in patients on ß-blocker therapy for chronic heart failure and with implantable cardioverter-defibrillators or cardiac resynchronization therapy defibrillators (CRT-Ds). Patients were grouped by average nHR and 24h-HR quartile during follow-up to estimate the respective incidence of nonarrhythmic death and device-treated ventricular tachycardia/fibrillation (VT/VF). RESULTS: The study cohort included 1330 patients (median age 69 years [interquartile range 61-77 years]; 41% [n = 550] with CRT-D; median follow-up 25 months [interquartile range 13-42 months]). Compared with patients in the lowest nHR quartile (≤57 beats/min) group, patients in the highest quartile group (>65 beats/min) had an increased risk of nonarrhythmic death (adjusted hazard ratio [AHR] 2.25; 95% confidence interval [CI] 1.13-4.50; P = .021) and VT/VF (AHR 1.98; 95% CI 1.40-2.79; P < .001) and were characterized by the lowest level of physical activity (P ≤ .0004 vs every other nHR quartiles). The highest 24h-HR quartile group (>75 beats/min) showed an increased risk of VT/VF (AHR 2.13; 95% CI 1.52-2.99; P < .001) and a weaker though significant association with nonarrhythmic mortality (AHR 1.80; 95% CI 1.00-3.22; P = .05) as compared with the lowest 24h-HR quartile group (≤65 beats/min). CONCLUSION: In remotely monitored patients with implantable cardioverter-defibrillator/CRT-D on ß-blocker therapy for heart failure, elevated heart rates (nHR >65 beats/min and 24h-HR >75 beats/min) were associated with increased mortality and VT/VF risk. nHR showed a stronger association than 24h-HR with worst prognosis and lowest physical activity.

Left Atrial Appendage Occlusion in Patients with Failure of Antithrombotic Therapy: Good Vibes from Early Studies.

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and predisposes patients to an increased risk of cardioembolic events (CE), such as ischemic stroke, TIA, or systemic embolism [...].

Uric acid significantly correlates with the presence of low-voltage areas at the endocardial mapping in patients with non-valvular atrial fibrillation.

BACKGROUND AND AIMS: Interest in the role of atrial substrate in maintaining Atrial Fibrillation (AF) is growing. Fibrosis is the culprit in the electrical derangement of the myocytes. Many cardiovascular risk factors are known to be linked to atrial scarring; among them Uric Acid (UA) is emerging. The purpose of our study is to find whether UA is associated with Left Atrium (LA) with pathological substrate. METHODS AND RESULTS: 81 patients who underwent radiofrequency transcatheter ablation for nonvalvular AF at the cardiological department of the Niguarda Hospital were enrolled in an observational, cross-sectional, single-center study. UA levels were analysed before the procedure. High density electroanatomic mapping of the LA was performed and patients were divided according to the presence or not of areas of pathological substrate (bipolar voltage <0.5 mV in sinus rhythm). 19 patients showed a LA with pathological substrate. These subjects showed a significant higher prevalence of persistent phenotype of AF (84.2 vs. 25.8%, p < 0.001). UA levels were significantly higher in the group of patients with LA with pathological substrate (6.8 ± 1.9 vs 5.3 ± 1.4 mg/dL, p < 0.001) as well as the prevalence of hyperuricemia (26.5 vs. 6.5%, p = 0.021). The association between uric acid LA with pathological substrate remains significant even after correction for confounding factors (age, left ventricular dysfunction, valvular disease, arrythmia phenotype and furosemide use) and also when the ratio UA/creatinine was evaluated. CONCLUSIONS: In a population of patients who underwent AF ablation, higher UA levels were significantly associated with pathological LA substrate at electro-anatomical mapping.

Left Bundle Branch Area Pacing over His Bundle Pacing: How Far Have We Come?

Implantable cardiac pacemakers have greatly evolved during the few past years, focusing on newer modalities of physiologic cardiac pacing [...].

Temporal association between drops in thoracic impedance and malignant ventricular arrhythmia: A longitudinal analysis of remote monitoring trends.

INTRODUCTION: Thoracic impedance (TI) drops measured by implantable cardioverter-defibrillators (ICDs) have been reported to correlate with ventricular tachycardia/fibrillation (VT/VF). The aim of our study was to assess the temporal association of decreasing TI trends with VT/VF episodes through a longitudinal analysis of daily remote monitoring data from ICDs and cardiac resynchronization therapy defibrillators (CRT-Ds). METHODS AND RESULTS: Retrospective data from 2384 patients were randomized 1:1 into a derivation or validation cohort. The TI decrease rate was defined as the percentage of rolling weeks with a continuously decreasing TI trend. The derivation cohort was used to determine a TI decrease rate threshold for a ≥99% specificity of arrhythmia prediction. The associated risk of VT/VF episodes was estimated in the validation cohort by dividing the available follow-up into 60-day assessment intervals. Analyses were performed separately for 1354 ICD and 1030 CRT-D patients. During a median follow-up of 2.0 years, 727 patients (30.4%) experienced 3298 confirmed VT/VF episodes. In the ICD group, a TI decrease rate of >60% was associated with a higher risk of VT/VF episode in a 60-day assessment interval (stratified hazard ratio, 1.42; 95% confidence interval (CI), 1.05-1.92; p = .023). The TI decrease preceded (40.8%) or followed (59.2%) the VT/VF episodes. In the CRT-D group, no association between TI decrease and VT/VF episodes was observed (p = .84). CONCLUSION: In our longitudinal analysis, TI decrease was associated with VT/VF episodes only in ICD patients. Preventive interventions may be difficult since episodes can occur before or after TI decrease.

Direct anchoring technique for pacing and defibrillation leads inserted through cephalic vein: insight for a single high-volume center.

BACKGROUND: Direct anchoring of PM and ICD leads over cephalic vein body is officially discouraged by manufactures due to a supposed risk of conductor fracture or insulation failure, however careful tightening of anchoring knots can probably prevent lead damage. Direct anchoring (DA) technique is routinely used in our center for all leads inserted by cephalic vein while standard anchoring sleeves are used to secure subclavian leads only. Aim of the study is to assess short- and long-term safety of cephalic direct anchoring technique. METHODS: All patients undergoing PM and ICD implantation in our center from November 2014 to March 2016 were consecutively enrolled. Primary endpoints were acute lead fracture, lead dislodgement and chronic lead failure. Secondary endpoint was a composite of short-term surgical complications (pocket hematoma, pneumothorax, and pericardial effusion) plus device infections. Subclavian leads secured with sleeve anchoring (SA) were used as control. RESULTS: A total of 550 leads were implanted in 310 consecutive patients. DA involved 323 leads (59%) while SA was used for 227 (41%). Median follow-up was 50 months (IQR 24-62 months). 17 lead malfunctions (3.1%) were observed during follow-up. No difference was observed between groups (10 DA vs. 7 SP, P=ns). Survival analysis found no difference between groups. Secondary endpoints were not statistically different between groups (5 vs. 1, P=0.08). CONCLUSIONS: Direct anchoring technique of PM and ICD leads is a safe technique and does not increase lead malfunction risk.