Invasive management of atrial tachycardias using a novel lattice-tip catheter combining high-density mapping and dual ablation properties: initial real-world experience.

BACKGROUND: Invasive management of atrial tachycardias(ATs) requires proper diagnosis of the mechanism followed by elimination of the responsible substrate. A novel lattice-tip catheter with both high-density mapping and dual ablation properties(radiofrequency-RF/pulsed field ablation-PFA) has been recently introduced for catheter ablation of atrial fibrillation. We present the first study to assess its performance in the management of ATs (diagnostic and therapeutic). METHODS: Patients with documented ATs were selected. Activation mapping was used for the establishment of the AT mechanism. Confirmation with entrainment was performed, whenever appropriate. Accuracy of the activation mapping in diagnosis, acute ablation efficacy, and procedural characteristics were the study endpoints. RESULTS: Twenty patients were included (12 cavotricuspid isthmus-dependent atrial flutters, 5 mitral flutters, 2 roof flutters, and 2 focal ATs). Proper diagnosis was established by activation mapping in all cases. The mean mapping time was 7.85 ± 3.06 min with 296.82 ± 150.9 mean mapping points/minute. The mean ablation time was 54.25 ± 42.97 s. Conversion to sinus rhythm during ablation was achieved in all cases with the exception of a roof flutter that converted to mitral flutter and a case of a parahisian AT in which ablation was not attempted. Patients that received ablation did not experience any arrhythmia recurrence in a mean follow up of 4.14 ± 0.91 months. No major or minor complications occurred. CONCLUSION: The lattice-tip catheter and its dedicated electroanatomical mapping system provided sufficiently detailed activation mapping for the diagnosis of the AT mechanism. The delivered lesions were highly effective acutely, with no adverse events. However, limitations exist and should be acknowledged.

Cardiac resynchronization therapy in heart failure based on Strauss criteria for left bundle branch block.

AIMS: The left bundle branch block (LBBB) is a strong predictor of response to cardiac resynchronization therapy (CRT). However, a significant number of patients do not respond to the treatment. The study sought to evaluate the impact of the stricter Strauss criteria for left bundle branch block (St-LBBB) on CRT response, hospitalizations, ventricular arrhythmia (VA) events and mortality. METHODS: This study is a retrospective analysis of prospectively collected data on heart failure (HF) patients with LBBB admitted for CRT implantation. Patients were divided into two groups according to the fulfilment or not of St-LBBB criteria. RESULTS: The study included 82 patients with ischaemic (ICM) and non-ischaemic (NICM) cardiomyopathy [46 (56%) with St-LBBB and 36 (44%) with non-St-LBBB]. Patients with St-LBBB showed higher CRT response rates compared with those with non-St-LBBB (P < 0.01), while the group with NICM exhibited the greatest benefit (P < 0.01). St-LBBB CRT responders displayed significantly lower rates of HF hospitalization (P < 0.0001) compared with the non-St-LBBB group. According to Kaplan-Meier time curves, this was primarily evident in patients with NICM (P < 0.0001). CRT responders displayed significantly fewer VA events (P < 0.001) and lower mortality rates (P < 0.0001) than non-responders. Kaplan-Meier estimates demonstrated a significantly lower incidence of VAs in NICM patients with St-LBBB (P = 0.049) compared with ICM patients with St-LBBB (P = 0.25). Lower mortality rates were observed in CRT responders than non-responders (P < 0.0001), with the group of NICM with St-LBBB criteria exhibiting the greatest benefit (P = 0.0238). CONCLUSIONS: Patients with NICM and St-LBBB present the greatest benefit concerning CRT response, HF hospitalizations, VA events and mortality. Although St-LBBB criteria seem to improve patient selection for CRT, more data are needed to elucidate the role of St-LBBB criteria in this setting.

Successful management of pulmonary hemorrhage from lung carcinoid, in a patient on VenoArterial extracorporeal membrane oxygenation support.

INTRODUCTION: A young man was referred to our Center for refractory cardiogenic shock, accompanied with uncontrolled atrial flutter of unknown duration. The patient was supported with VenoArterial Extracorporeal Membrane Oxygenation (VA ECMO) and Intra-Aortic Balloon Pump (IABP) as a bridge to decision. CASE REPORT: His course was complicated by pulmonary hemorrhage due to an unknown endobronchial mass. A low-grade typical carcinoid without metastases was revealed during work up. He was treated successfully with bronchoscopy-guided interventional therapies and cavo-tricuspid isthmus ablation. Mechanical support was successfully weaned off and 3 months after discharge, he was asymptomatic with no sign of residual tumor. DISCUSSION: Endobronchial treatment is a parenchyma-preserving alternative to surgery, with a comparable recurrence rate, especially in patients with typical carcinoid. CONCLUSION: This is the first case report describing the successful management of pulmonary hemorrhage due to lung carcinoid, in a patient supported with VA ECMO for cardiogenic shock.

Incidence and predictors of post-surgery atrial fibrillation occurrence: A cohort study in 53,387 patients.

Introduction: Atrial fibrillation (AF) represents the most common arrhythmia in the postoperative setting. We aimed to investigate the incidence of postoperative AF (POAF) and determine its predictors, with a specific focus on inflammation markers. Methods: We performed a retrospective single tertiary center cohort study including consecutive adult patients who underwent a major surgical procedure between January 2016 and January 2020. Patients were divided into four subgroups according to the type of surgery. Results: Among 53,387 included patients (79.4% male, age 64.5 ± 9.5 years), POAF occurred in 570 (1.1%) with a mean latency after surgery of 3.4 ± 2.6 days. Ninety patients died (0.17%) after a mean of 13.7 ± 8.4 days. The 28-day arrhythmia-free survival was lower in patients undergoing lung and cardiovascular surgery (p < .001). Patients who developed POAF had higher levels of C-reactive protein (CRP) (0.70 ± 0.03 vs. 0.40 ± 0.01 log10 mg/dl; p < .001). In the multivariable Cox regression analysis, adjusting for confounding factors, CRP was an independent predictor of POAF [HR per 1 mg/dL increase in log-scale = 1.81 (95% CI 1.18-2.79); p = .007]. Moreover, independent predictors of POAF were also age (HR/1 year increase = 1.06 (95% CI 1.04-1.08); I < .001), lung and cardiovascular surgery (HR 23.62; (95% CI 5.65-98.73); p < .001), and abdominal and esophageal surgery (HR 6.26; 95% CI 1.48-26.49; p = .013). Conclusions: Lung and cardiovascular surgery had the highest risk of POAF in the presented cohort. CRP was an independent predictor of POAF and postsurgery inflammation may represent a major driver in the pathophysiology of the arrhythmia.

The Combination of Hyperuricemia and Elevated High-Sensitivity C-Reactive Protein Increased the Risk of Cardiac Conduction Block.

Objective: This study aimed to explore the impact of a combination of hyperuricemia (HUA) and excessive high-sensitivity C-reactive protein (hs-CRP) levels on the likelihood of developing cardiac conduction block (CCB). Additionally, it sought to assess whether the influence of uric acid (UA) on CCB is mediated by hs-CRP. Methods: A prospective study was executed utilizing data from the Kailuan cohort, including 81,896 individuals initially free from CCB. The participants were categorized into four groups depending on the existence of HUA and low-grade inflammation (hs-CRP>3 mg/L). Cox regression analysis was employed to ascertain hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of incident CCB. A mediation analysis was performed to determine if hs-CRP functioned as a mediator in the connection between UA levels and the incidence of CCB. Results: During a median observation period of 11.8 years, we identified 3160 cases of newly occurring CCB. Compared with the low UA/low CRP group, the combination of HUA and low-grade inflammation elevated the CCB risks (HR:1.56, 95% CI:1.22-1.99), atrioventricular block (AVB) (HR:1.88, 95% CI:1.27-2.77), and right bundle branch block (HR:1.47, 95% CI:1.02-2.12), respectively. Mediation analysis revealed that in the HUA group, compared with the non-HUA group, the risk of CCB elevated by 14.0%, with 10.3% of the increase mediated through hs-CRP. Conclusion: HUA combined with elevated hs-CRP increased the risk of CCB, especially AVB. The connection between UA and the CCB risk was partly mediated by hs-CRP.

Diagnostic yield of implantable loop recorders: results from the hellenic registry.

OBJECTIVE: Implantable loop recorders (ILRs) are increasingly being used for long-term cardiac monitoring in different clinical settings. The aim of this study was to investigate the real-world performance of ILRs-including the time to diagnosis-in unselected patients with different ILR indications. METHODS AND RESULTS: In this multicenter, observational study, 871 patients with an indication of pre-syncope/syncope (61.9%), unexplained palpitations (10.4%), and atrial fibrillation (AF) detection with a history of cryptogenic stroke (CS) (27.7%) underwent ILR implantation. The median follow-up was 28.8 ± 12.9 months. In the presyncope/syncope group, 167 (31%) received a diagnosis established by the device. Kaplan-Meier estimates indicated that 16.9% of patients had a diagnosis at 6 months, and the proportion increased to 22.5% at 1 year. Of 91 patients with palpitations, 20 (22%) received a diagnosis based on the device. The diagnosis was established in 12.2% of patients at 6 months, and the proportion increased to 13.3% at 1 year. Among 241 patients with CS, 47 (19.5%) were diagnosed with AF. The diagnostic yield of the device was 10.4% at 6 months and 12.4% at 1 year. In all cases, oral anticoagulation was initiated. Overall, ILR diagnosis altered the therapeutic strategy in 26.1% of the presyncope/syncope group, 2.2% of the palpitations group, and 3.7% of the CS group in addition to oral anticoagulation initiation. CONCLUSION: In this real-world patient population, ILR determines diagnosis and initiates new therapeutic management for nearly one-fourth of patients. ILR implantation is valuable in the evaluation of patients with unexplained presyncope/syncope, CS, and palpitations.

Association of beat-to-beat P-wave analysis index to the extent of left atrial low-voltage areas in patients with paroxysmal atrial fibrillation.

BACKGROUND: Left atrial (LA) fibrosis has been shown to be associated with atrial fibrillation (AF) recurrence. Beat-to-beat (B2B) index is a non-invasive classifier, based on B2B P-wave morphological and wavelet analysis, shown to be associated with AF incidence and recurrence. In this study, we tested the hypothesis that the B2B index is associated with the extent of LA low-voltage areas (LVAs) on electroanatomical mapping. METHODS: Patients with paroxysmal AF scheduled for pulmonary vein isolation, without evident structural remodeling, were included. Pre-ablation electroanatomical voltage maps were used to calculate the surface of LVAs (<0.5 mV). B2B index was compared between patients with small versus large LVAs. RESULTS: 35 patients were included (87% male, median age 62). The median surface area of LVAs was 7.7 (4.4-15.8) cm2 corresponding to 5.6 (3.3-12.1) % of LA endocardial surface. B2B index was 0.57 (0.52-0.59) in patients with small LVAs (below the median) compared to 0.65 (0.56-0.77) in those with large LVAs (above the median) (p = 0.009). In the receiver operator characteristic curve analysis for predicting large LVAs, the c-statistic was 0.75 (p = 0.006) for B2B index and 0.81 for the multivariable model including B2B index (multivariable p = 0.04) and P-wave duration. CONCLUSION: In patients with paroxysmal AF without overt atrial myopathy, B2B P-wave analysis appears to be a useful non-invasive correlate of low-voltage areas-and thus fibrosis-in the LA. This finding establishes a pathophysiological basis for B2B index and its potential usefulness in the selection process of patients who are likely to benefit most from further invasive treatment.

Analysis of the effectiveness of the latest 4th-generation cryoballoon catheters in pulmonary vein isolation using high-resolution mapping.

BACKGROUND: Long-term data showed that up to 27% of pulmonary veins are reconnected using cryoballoon ablation. This study aimed to evaluate the efficacy of the latest 4th-generation cryoballoon catheters using ultra high-resolution mapping. METHODS: In patients with atrial fibrillation, a standard pulmonary vein isolation (PVI) with the latest 4th-generation cryoballoon catheter (Arctic Front Advance PRO, Medtronic Minneapolis, USA) and the spiral mapping catheter (Achieve Advance, Medtronic, Minneapolis, MN, USA) was performed. Subsequently, high-resolution mapping was achieved using the novel multipolar grid mapping catheter (Advisor HD Grid SE, Abbott Laboratories, USA). Follow-up was obtained after 6 months by means of a 7-day Holter electrocardiogram. RESULTS: In our study, acute PVI was successfully achieved in all 31 patients. The latest 4th-generation cryoballoon catheter is safe in the acute phase of PVI. Additional high-resolution mapping (mean points per map 21,001 ± 4911) using the multipolar grid mapping catheter enabled us to identify residual gaps only in the carina pulmonary vein region; therefore, no additional ablation was performed. Three of 31 patients (10%) presented with atrial arrhythmia recurrence always related with pulmonary vein reconnection; using high-resolution mapping had no additional benefit in identifying pulmonary veins in which reconnection will occur. CONCLUSION: The utility of additional high-density mapping, facilitated by the HD Grid catheter after PVI with the 4th-generation cryoballoon catheter do not substantiate a discernible advantage over conventional mapping methodologies, particularly, the spiral mapping catheter. Residual carinal conduction was observed in a substantial cohort of patients (48%), highlighting a persistent challenge in achieving complete electrical isolation.

Efficacy and safety of colchicine for atrial fibrillation prevention: An updated meta-analysis of randomized controlled trials.

BACKGROUND: Atrial fibrillation (AF), the most common arrhythmia, is closely related to inflammation. Colchicine has the potent anti-inflammatory effects. Several randomized clinical trials (RCTs) have evaluated the efficacy and safety of colchicine in the prevention of AF but the results are inconsistent. OBJECTIVE: The purpose of our study was to evaluate the impact of colchicine on AF. METHOD AND RESULTS: PubMed, EMBASE, Web of Science, Cochrane Library and ClinicalTrials.gov were searched for related studies until Jan 8, 2024. A total of 17 studies including 16,238 participants were included. Compared to the placebo group, there were fewer incidences of AF in the colchicine group (RR: 0.75, 95%CI: 0.68-0.83, P < 0.001). The incidence of overall adverse events and overall gastrointestinal intolerance did not differ significantly between the two groups. However, diarrhea, nausea, and discontinuation occurred more frequently in patients treated with colchicine. CONCLUSION: Colchicine can prevent patients from the incidence of AF, regardless of the mean age of patients, type of atrial fibrillation, maintenance dose, duration of colchicine use, cumulative daily dose, and follow-up time with more diarrhea, nausea and discontinuation. These adverse events can be avoided by low doses (0.5 mg once daily) and long period time of colchicine use.

Atrial fibrillation in the setting of cardiac amyloidosis - A review of the literature.

Cardiac amyloidosis (CA) is related to the aggregation of insoluble fibrous deposits of misfolded proteins within the myocardium. Transthyretin amyloidosis (ATTR) and immunoglobulin light-chain amyloidosis are the main forms of CA. Atrial fibrillation (AF) is a common arrhythmia in CA patients, especially in those with ATTR amyloidosis. Increased atrial preload and afterload, atrial enlargement, enhanced atrial wall stress, and autonomic dysfunction are the main mechanisms of AF in CA patients. CA is associated with the formation of endocardial thrombi and systemic embolism. The promoters of thrombogenesis include endomyocardial damage, blood stasis, and hypercoagulability. The prevalence of thrombi in patients with AF remains elevated despite long-term anticoagulation. Consequently, transesophageal ultrasound examinations before cardioversion should be performed to exclude endocardiac thrombi despite anticoagulation. Furthermore, the CHA2DS2-VASc score should not be used to assess the thromboembolic risk in CA patients with AF. Rate control is challenging in patients with CA, while rhythm control is the preferred treatment option, especially in the early stages of the disease process. Although catheter ablation is an effective treatment option, more data are needed to explore the role of the procedure in CA patients.

Cryoablation versus hybrid radiofrequency with high- and very-high-power short-duration catheter ablation for the treatment of paroxysmal atrial fibrillation.

BACKGROUND: High-power short-duration (HPSD) and very-high-power short-duration (vHPSD-90 W/4 s) radiofrequency (RF) technology has reduced the procedure time of pulmonary vein isolation (PVI) using RF without compromising the efficacy of the technique. The current study compares the novel technology of HPSD/vHPSD with cryoablation (CRYO) in terms of efficacy, safety, and procedure time in a cohort of symptomatic patients with paroxysmal atrial fibrillation (pAF). METHODS: This is a prospective, non-randomized trial. Patients with pAF received either CRYO or HPSD/vHPSD RF PVI. The primary endpoint of the study was arrhythmia recurrence in a 12 month follow-up period. Secondary endpoints included procedure time, fluoroscopy time, and safety. RESULTS: 104 patients were included (45 in HPSD/vHPSD and 59 in CRYO), with comparable characteristics between groups. The follow-up was 12.4 ± 0.5 months. There was no significant difference regarding arrhythmia recurrences during the early post-procedural period of the first 3 months (8.9% recurrences in HPSD/vHPSD versus 5.1% in CRYO-p 0.463) and in the mid-term follow-up of 12 months (17.8% recurrences in HPSD/vHPSD versus 10.2% in CRYO-p 0.385). Safety was excellent for both procedures. CRYO was a procedure of significantly shorter duration (64.64 ± 8.94 min versus 75.29 ± 18.30 min, p = 0.0001) at the expense of longer fluoroscopy time (HPSD/vHPSD 5.34 ± 1.83 versus 7.89 ± 3.70 min CRYO, p 0.001). CONCLUSIONS: HPSD/vHPSD and CRYO in pAF were comparable regarding the arrhythmia recurrence rates in a 12-month follow-up with excellent safety. The hybrid approach of HPSD/vHPSD has accelerated RF-PVI compared to conventional RF, but CRYO remains a procedure of significantly shorter duration at the expense of longer fluoroscopy time.

Cardiac contractility modulation in patients with heart failure - A review of the literature.

Experimental in vivo and in vitro studies showed that electric currents applied during the absolute refractory period can modulate cardiac contractility. In preclinical studies, cardiac contractility modulation (CCM) was found to improve calcium handling, reverse the foetal myocyte gene programming associated with heart failure (HF), and facilitate reverse remodeling. Randomized control trials and observational studies have provided evidence about the safety and efficacy of CCM in patients with HF. Clinically, CCM therapy is indicated to improve the 6-min hall walk, quality of life, and functional status of HF patients who remain symptomatic despite guideline-directed medical treatment without an indication for cardiac resynchronization therapy (CRT) and have a left ventricular ejection fraction (LVEF) ranging from 25 to 45%. Although there are promising results about the role of CCM in HF patients with preserved LVEF (HFpEF), further studies are needed to elucidate the role of CCM therapy in this population. Late gadolinium enhancement (LGE) assessment before CCM implantation has been proposed for guiding the lead placement. Furthermore, the optimal duration of CCM application needs further investigation. This review aims to present the existing evidence regarding the role of CCM therapy in HF patients and identify gaps and challenges that require further studies.

Association of Late Potentials With Fatal Arrhythmic Events in Patients With Brugada Syndrome-A Meta-analysis.

Risk stratification of patients with Brugada syndrome (BrS) remains challenging. Signal-averaged electrocardiogram (SAECG) is a noninvasive tool that can be used to identify the electrophysiologic substrate potentially underlying fatal ventricular arrhythmias. The aim of this meta-analysis is to summarize the existing evidence about the role of late potentials (LP) as a predictor for arrhythmic events in patients with BrS. A systematic search in the MedLine database through to June 2022 without any limitations was performed. Ten studies were included in the quantitative synthesis (1431 patients with BrS, mean age 47.4 years, males 86%). Of these, 1220 patients underwent SAECG evaluation (53.2% had positive LP, and 20.6% had a fatal arrhythmic event). There was a nonsignificant association between positive LPs and fatal arrhythmic events [RR: 2.06 (0.98-4.36), P = 0.06, I2 = 82%]. By including only studies with patients without a history of fatal arrhythmia, the association between LP with arrhythmic events remained nonsignificant [RR: 1.29 (0.67-2.48), P = 0.44, I2 = 54%]. In conclusion, there is a possible association between LP and fatal arrhythmic events in patients with BrS, but the literature remains inconclusive. Large cohort studies using a multiparametric approach for risk stratification purposes are needed to improve the risk stratification of BrS and to optimize the selection of BrS patients that should be referred for implantable cardioverter-defibrillator.

An inappropriately-appropriate ICD therapy: What is the mechanism and what interventions can be done?

Key Clinical Message: R-wave double counting is a rare cause of ventricular oversensing that can lead to inappropriate shocks. Optimizing device programming is essential for the avoidance of subsequent inappropriate therapies. Abstract: R-wave double counting is a rare cause of ventricular oversensing that can lead to inappropriate shocks. We present the case of a female patient, 52-years-old with a history of end-stage hypertrophic cardiomyopathy. The patient suffered an implantable cardioverter-defibrillator (ICD) shock. Cardiac device interrogation revealed ventricular tachycardia (VT) with a cycle length of 420 ms that was misclassified in the ventricular fibrillation (VF) zone owing to R-wave double counting. Optimizing device programming is essential for the avoidance of subsequent inappropriate therapies. Possible therapeutic options are briefly presented in the case.

Contemporary management of ventricular arrhythmias in heart failure.

Enhanced ventricular arrhythmogenesis is commonly experienced by patients in the end-stage of heart failure spectrum. A high burden of ventricular arrhythmias can affect the ventricular systolic function, lead to unexpected hospitalizations and further deteriorate the prognosis. Management of ventricular arrhythmias in this population is challenging. Implantable cardioverter-defibrillators are protective for the immediate termination of life-threatening arrhythmias but they have no impact in reducing the arrhythmic burden. Combination treatment with invasive (catheter ablation, mechanical hemodynamic support, sympathetic denervation) and noninvasive (antiarrhythmic drugs, medical therapy for heart failure, programming of implantable devices) therapies is commonly required. The aim of this review is to present the available therapeutic options, with main focus on recently published data for catheter ablation and provide a stepwise treatment approach.

Cardioneuroablation for neurally-mediated syncope: Initial experience.

Cardioneuroablation is an emerging alternative therapeutic modality for young patients with severe neurally-mediated syncope. We present two images of cardioneuroablation performed in young patients who suffered from recurrent neurally-mediated syncope with asystole and functional atrioventricular block. The patients remain syncope-free during follow-ups.

Electrocardiographic changes after balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension: Data from the Hellenic Registry.

BACKGROUND: Balloon pulmonary angioplasty (BPA) has provided an effective invasive treatment for inoperable patients with chronic thromboembolic pulmonary hypertension (CTEPH). The hemodynamic improvement achieved by BPA has significantly increased the long-term prognosis of these patients, mostly by reversing the negative remodeling of the right ventricle (RV). MATERIALS AND METHODS: In a cohort of 17 patients with symptomatic CTEPH hemodynamic data were collected before and after the completion of BPA sessions. After the confirmation of statistically significant hemodynamic improvement, we examined the changes in certain prespecified electrocardiographic (ECG) parameters (PR interval duration, QRS duration, QTc interval duration, R wave and S wave amplitude in lead I, R wave and S wave amplitude in precordial leads V1, V5 and V6) before the initiation and one month after the completion of BPA sessions. In addition, ECGs were qualitatively assessed before and after treatment for the presence of ECG abnormalities related to PH, proposed by the guidelines of the European Society of Cardiology (ESC). The term ESC criteria 1-6 was used for their description. RESULTS: Statistically significant correlation (p < 0.05) was found between the reduction in mean pulmonary artery pressure (mPAP) and the decrease of the depth of the S wave in leads I (p 0.0069), V5 (p 0.0003), V6 (p 0.0011) and in the R wave amplitude in leads V5 (p 0.0122) and V6 (p 0.0185). From the ESC criteria, RV strain pattern was the commonest in the initial cohort, with significant improvement after therapies. CONCLUSION: Hemodynamic improvement after BPA therapies is correlated with improved ECG amplitude parameters in leads I, V5 and V6. RV strain pattern is common among untreated patients with significant improvement after therapies.