Arrhythmic Episodes Research Articles

Impact of pulmonary veins anatomy on the outcomes of radiofrequency ablation for paroxysmal atrial fibrillation in the era of contact force-sensing ablation catheters.

Pulmonary vein (PV) isolation (PVI) has become the cornerstone of atrial fibrillation (AF) ablation in patients with paroxysmal AF (PAF). PVI durability is influenced by many factors including PVs anatomy. Data regarding the influence of PVs anatomical variations on the outcomes of PAF ablation in the era of contact force-sensing ablation catheters are scarce and contradictory. Consecutive patients referred to our center for a first ablation of PAF using radiofrequency (RF) were included. PVs anatomy was classified into 3 groups: typical anatomy (4 distinct veins), left common ostium (LCO), and right accessory PV (RAPV). The primary outcome was recurrence of atrial arrhythmia episode during a 12-month follow-up after ablation. Two hundred twenty-three patients were included (mean age 58.4 ± 10.8years and 70.9% male). Among this cohort, 141 patients (63.2%) had typical PV anatomy, 53 (23.8%) had a LCO, and 29 (13.0%) had a RAPV. The existence of a RAPV was not associated with a higher rate of AF recurrences (22 (14.3%) vs. 7 (10.1%), p = 0.519). After multivariate analysis, the presence of an LCO did not appear to be associated with the AF recurrence rate at 12months (OR = 1.69, 95%CI 0.95-2.49, p = 0.098). Maintenance of antiarrhythmic drugs after ablation was the only factor independently associated with a decreased risk of AF recurrence at 12months (OR = 0.76, 95%CI 0.60-0.97, p = 0.046). This study suggests that the presence of an LCO or a RAPV is not associated with a higher rate of AF recurrence at 12months after radiofrequency PVI using contact force-sensing catheters in PAF patients.

Cardiac arrhythmia diagnosis applying machine learning techniques

Cardiac arrhythmia affects millions of people worldwide. Although commonly occurring, identifying and correctly diagnosing is not a simple task. In this context, this paper presents a study on the application of Machine Learning to the identification and diagnosis of cardiac arrhythmias. Classifiers were obtained using the k-NN and SVM algorithms, and tests were performed using data from the Arrhythmia dataset, which consists of information obtained from patients' ECG examinations, as well as information related to their lifestyles. Three tests were performed; in the first one, the ability of classifiers to identify whether or not an arrhythmia episode occurred. In the second one, the performance of the classifiers in the identification of the arrhythmia type was verified, and in the third one, the investigation was performed considering the gender of the individuals. The results indicate that the use of Machine Learning may, in fact, assist specialists in the diagnosis of arrhythmias. In all tests k-NN presented better performance when compared to SVM. The best result among all tests was obtained by gender classification, where k-NN presented a accuracy of 94.03% in identifying arrhythmia occurrences in female patients.

Safety and efficacy of ranolazine in hypertrophic cardiomyopathy: Real-world experience in a National Referral Center

ObjectivesWe assessed the efficacy and safety of ranolazine in real-world patients with hypertrophic cardiomyopathy (HCM). BackgroundRanolazine is an anti-anginal drug that inhibits the late phase of the inward sodium current. In a small prospective trial, ranolazine reduced the arrhythmic burden and improved biomarker profile in HCM patients. However, systematic reports reflecting real-world use in this setting are lacking. MethodsChanges in clinical and instrumental features, symptoms and arrhythmic burden were evaluated in 119 patients with HCM before and during treatment with ranolazine at a national referral centre for HCM. ResultsPatients were treated with ranolazine for 2 [1–4] years; 83 (70%) achieved a dosage ≥1000 mg per day. Treatment interruption was necessary in 24 patients (20%) due to side effects (n = 10, 8%) or disopyramide initiation (n = 8, 7%). Seventy patients (59%) were treated with ranolazine for relief of angina. Among them, 51 (73%) had total symptomatic relief and 47 patients (67%) showed ≥2 Canadian Cardiovascular society (CCS) angina grade improvement. Sixteen patients (13%) were treated for recurrent ventricular arrhythmias, including 4 with a clear ischemic trigger, who experienced no further arrhythmic episodes while on ranolazine. Finally, 33 patients (28%) were treated for heart failure associated with severe diastolic dysfunction: no symptomatic benefit could be observed in this group. ConclusionRanolazine was safe and well tolerated in patients with HCM. The use of ranolazine may be considered in patients with HCM and microvascular angina.

Efficacy and Safety of an Extravascular Implantable Cardioverter–Defibrillator

BackgroundThe extravascular implantable cardioverter–defibrillator (ICD) has a single lead implanted substernally to enable pause-prevention pacing, antitachycardia pacing, and defibrillation energy similar to that of transvenous ICDs. The safety and efficacy of extravascular ICDs are not yet known.MethodsWe conducted a prospective, single-group, nonrandomized, premarket global clinical study involving patients with a class I or IIa indication for an ICD, all of whom received an extravascular ICD system. The primary efficacy end point was successful defibrillation at implantation. The efficacy objective would be met if the lower boundary of the one-sided 97.5% confidence interval for the percentage of patients with successful defibrillation was greater than 88%. The primary safety end point was freedom from major system- or procedure-related complications at 6 months. The safety objective would be met if the lower boundary of the one-sided 97.5% confidence interval for the percentage of patients free from such complications was greater than 79%.ResultsA total of 356 patients were enrolled, 316 of whom had an implantation attempt. Among the 302 patients in whom ventricular arrhythmia could be induced and who completed the defibrillation testing protocol, the percentage of patients with successful defibrillation was 98.7% (lower boundary of the one-sided 97.5% confidence interval [CI], 96.6%; P<0.001 for the comparison with the performance goal of 88%); 299 of 316 patients (94.6%) were discharged with a working ICD system. The Kaplan–Meier estimate of the percentage of patients free from major system- or procedure-related complications at 6 months was 92.6% (lower boundary of the one-sided 97.5% CI, 89.0%; P<0.001 for the comparison with the performance goal of 79%). No major intraprocedural complications were reported. At 6 months, 25 major complications were observed, in 23 of 316 patients (7.3%). The success rate of antitachycardia pacing, as assessed with generalized estimating equations, was 50.8% (95% CI, 23.3 to 77.8). A total of 29 patients received 118 inappropriate shocks for 81 arrhythmic episodes. Eight systems were explanted without extravascular ICD replacement over the 10.6-month mean follow-up period.ConclusionsIn this prospective global study, we found that extravascular ICDs were implanted safely and were able to detect and terminate induced ventricular arrhythmias at the time of implantation. (Funded by Medtronic; ClinicalTrials.gov number, NCT04060680.)

Ventricular tachycardia ablation before an implantable cardioverter defibrillator in secondary prevention: is always the best option?

Abstract Background Among patients with an aborted episode of malignant ventricular arrhythmias without a reversible cause, the Implantable Cardioverter Defibrillator (ICD) is considered an important therapy for secondary prevention of sudden cardiac death (SCD). Some authors propose primary catheter ablation and deferred ICD implantation may be the preferred approach in patients with substrate-related ventricular tachycardia. Purpose We want to evaluate the need of secondary time ablation in patients with secondary prevention ICD, when submitted only a medical therapy after the index event. Methods We conducted a retrospective, observational study of 90 patients who consecutively implanted ICD after an aborted episode of malignant ventricular arrhythmias without a reversible/known cause between 2014 and 2020. Patients with Brugada Syndrome, Wolff-Parkinson-White syndrome, QT related diseases and previous ventricular tachycardia (VT) ablation were excluded. Baseline clinical characteristics were analyzed, and a 1-year follow-up was performed: cardiovascular (CV) death, sustain VT), ventricular fibrillation (VF), antitachycardia pacing (ATP), ICD shock, VT ablation. Results Mean age was 58±18 years, 80% (n=72) were male and 65.5% (n=59) had a non-ischemic etiology. Most of the patients (61%; n=56) present with hemodynamic unstable VT or syncope, and 38% (n=34) with SCD [most due to VF (n=30)]. After the index event 41.1% (n=37) and 83.8% (n=75) initiate antiarrhythmic and beta-blocker (BB), respectively. During 1-year follow-up (FUP) 11.1% (n=10) had a sustain VT and 2.2% (n=2) VF leading to ATP and appropriated shock in 11.1% (n=10) and 10% (n=9), respectively. There was 2 CV death [due to acute heart failure (HF)], 8 HF hospitalization and 3 VT ablation during follow-up. The presence of chronic kidney disease at baseline was the only parameter related to 1-year CV death (1.3% vs 18.2%, p=0.039) and HF hospitalization (0% vs 18.2%, p=0.014). The antiarrhythmic after index event was associated with a significant less sustain VT [10% vs 45%, OR 0.114 (IC 95% 0.014 to 0.927] and consequently ATP (adjusted for age) and had a numerical benefit in ICD shock (2.7% vs 15.1%, p=0.076) and need of a secondary time ablation (0% vs 5.7%, p=0.266). Conclusion The ICD implant with antiarrhythmic therapy, as a primary approach to secondary prevention (vs ablation), after an aborted episode of malignant ventricular arrhythmias still showed to be a secure and viable first option. Funding Acknowledgement Type of funding sources: None.

Geomagnetic Disturbances and Ventricular Arrhythmia in Patients with Implantable Cardioverter Defibrillators from a US-Based Hospital

Background and Aim: Episodes of ventricular arrhythmias (VA) have been associated with environmental exposures such as air pollution. Solar driven geomagnetic disturbances may alter autonomic nervous system activity, modify systemic oxidative stress, or induce changes in aerosols. However, few studies have investigated if there is an association between VA and geomagnetic disturbances (GMD). The aim of this study was to assess whether GMD is associated with the initiation of VA in patients with implantable cardioverter defibrillators (ICDs). Methods: This study examined the association between GMD driven by solar activity on VA, defined as sustained and non-sustained ventricular fibrillation or ventricular tachycardia, in patients with ICDs using a time-stratified case-crossover analysis between September 2006 and March 2010 from Tufts Medical Center’s Cardiac Arrythmia Center in Boston, MA. Patients were identified from a single Massachusetts-based Medical Center and VAs were identified from retrieved ICD records as part of routine care. We considered several pollutants such as PM2.5, black carbon (BC), O3, NO2 and ultrafine particles (PN) in our analyses using time lags prior to the event. Daily GMD information was appended for the week previous to each event and matched control day. Results: During the study period, 91 patients had a total of 1,050 VA. During periods of increased GMD, patients with low ejection fraction and a history of a MI or coronary intervention had increased odds of VA , with patients who had a coronary bypass graph being the highest (OR: 1.63, 95% CI 1.05, 2.52 ). Conclusions: Among patients with ICDs, exposure to GMD was associated with higher odds of VA in those with pre-existing heart disease and/or a history of coronary interventions. GMD driven by solar activity has the potential to affect heart health in patients with cardiac comorbidities. Keywords: Solar activity, geomagnetic disturbances, implantable cardioverter defibrillator, ventricular arrhythmia

Contrast defect of left atrial appendage on computed tomography is associated with higher risk of recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

The previous study has shown that the contrast defect of the left atrial appendage (LAA) on contrast-enhanced cardiac computed tomography (CT) is associated with a higher rate of stroke in patients with atrial fibrillation (AF). This study aimed to investigate the association between LAA CT contrast defect and the risk of arrhythmia recurrence after catheter ablation (CA) in patients with paroxysmal AF. A total of 283 paroxysmal AF patients [age: 67 ± 10years, 185 (65%) males] who underwent cardiac CT before CA were retrospectively analyzed. The presence or absence of LAA CT contrast defect was visually assessed using early phase CT images. Recurrence was an episode of atrial arrhythmia beyond the first 90days post-ablation. LAA flow velocity was measured using transesophageal echocardiography in 246 paroxysmal AF patients. Sixty-eight (24%) patients had an LAA CT contrast defect. LAA flow velocity was significantly reduced in patients with LAA CT defect compared to those without (56.8 ± 28.7cm/s vs. 41.1 ± 19.1cm/s, p < 0.001). During a median follow-up period of 858days, arrhythmia recurrence was identified in 85 (30%) patients. On a Kaplan Meier curve, patients with LAA CT contrast defect had significantly higher recurrence rates than those without (p = 0.043). On a multivariable Cox regression analysis, LAA CT contrast defect was a significant and independent predictor after adjustment of age, sex and left atrial volume index (hazard ratio: 1.79, 95% confidence interval: 1.03-3.07, p = 0.036). LAA CT contrast defect was associated with decreased LAA flow velocity and a higher rate of arrhythmia recurrence after CA, suggesting its usefulness as a non-invasive predictor for high-risk AF patients resistant to CA therapy.

The Impact of a Modified Anaesthetic Protocol on Animal Survival and the Characteristics of Ventricular Arrhythmias in the Course of Acute Myocardial Infarction in a Domestic Pig Model.

Acute myocardial infarction (MI) is one of the most common causes of death in humans in highly developed countries. Among its most frequent complications affecting the patient's prognosis are cardiac arrhythmias: ventricular tachycardia (VT) and ventricular fibrillation (VF). The study aimed to characterise arrhythmias in 19 pigs subjected to experimentally induced MI obtained by occlusion of the proximal left anterior descending (LAD) coronary artery using an angioplasty balloon. The anaesthetic protocol was modified to reduce mortality by including procedures stabilising haemodynamic disorders which develop during episodes of ischaemia and arrhythmia. During 30 min of experimentally induced ischaemia, the heart rhythm was recorded using a 12-lead ECG. The time, frequency, and type of arrhythmias were analysed. Ventricular arrhythmias were found in 94.74% of the treated pigs. The most common were ventricular premature complexes, reported in 88.89% of pigs with arrhythmia. Ventricular tachycardia was recorded in 66.67% and ventricular fibrillation in 50% of pigs with arrhythmias. Myocardial infarction due to proximal LAD occlusion is characterised by a high incidence of ventricular arrhythmias, especially VT and VF. Because of the high survival rate, this MI porcine model may serve as a model for research on acute ischaemic ventricular arrhythmias in humans. Additionally, it reduces the total number of animals required for testing while yielding meaningful results, which is in line with the 3R principle.

The Challenges of Diagnosis and Treatment of Arrhythmogenic Cardiomyopathy: Are We there yet?

we sought to review the evolution in the diagnosis and treatment of Arrhythmogenic Cardiomyopathy (ACM), a clinically multifaceted entity beyond the observation of ventricular arrhythmias, and the outcome of therapies aiming at sudden death prevention in a single center experience. retrospective analysis of the data of consecutive patients with an implanted cardioverter-defibrillator (ICD) and a confirmed diagnosis of ACM according to the proposed Padua Criteria, who were referred to our center from January 1992 to October 2021. we enrolled 72 patients (66% males, mean age at implant 46 16 years), 63.9% implanted for primary prevention. At the time of ICD implant, 29 (40.3%) patients had a right ventricular involvement, 24 (33.3%) had a dominant LV involvement and 19 (26.4%) had a biventricular involvement. After a median follow-up of 6,1 years [IQR: 2.5-9.9], 34 patients (47.2%) had 919 sustained episodes of ventricular arrhythmias (VA). 27 patients (37.5%) had 314 episodes of life-threatening arrhythmias (LT-VA), defined as sustained ventricular tachycardia 200 beats/min. Considering only the patients with an ICD capable of delivering ATP, 80.4% of VA and 65% of LT-VA were successfully terminated with ATP. 16 (22.2%) patients had an inappropriate ICD activation, mostly caused by atrial fibrillation, while in 9 patients (12.5%) there was a complication needing reintervention (in 3 cases there was a loss of ventricular sensing dictating lead revision). During the follow-up 11 (15.3%) patients died, most of them due to heart failure, and 8 (11.1%) underwent heart transplantation. ACM is increasingly diagnosed owing to heightened suspicion at ECG examination and to improved imaging technology and availability, though the diagnostic workflow is particularly challenging in the earliest disease stages. ICD therapy is the cornerstone of sudden death prevention, albeit its efficacy is not based on controlled studies, and VT ablation/medical therapy are complementary to this strategy. The high burden of ATP-terminated VA makes shock-only devices debatable. The progressive nature of ACM leads to severe biventricular enlargement and refractory heart failure, which pose significant treatment issues when a predominant RV dysfunction occurs owing to the reduced possibility for mechanical circulatory assistance.

Personalized ablation vs. conventional ablation strategies to terminate atrial fibrillation and prevent recurrence.

The long-term success rate of ablation therapy is still sub-optimal in patients with persistent atrial fibrillation (AF), mostly due to arrhythmia recurrence originating from arrhythmogenic sites outside the pulmonary veins. Computational modelling provides a framework to integrate and augment clinical data, potentially enabling the patient-specific identification of AF mechanisms and of the optimal ablation sites. We developed a technology to tailor ablations in anatomical and functional digital atrial twins of patients with persistent AF aiming to identify the most successful ablation strategy. Twenty-nine patient-specific computational models integrating clinical information from tomographic imaging and electro-anatomical activation time and voltage maps were generated. Areas sustaining AF were identified by a personalized induction protocol at multiple locations. State-of-the-art anatomical and substrate ablation strategies were compared with our proposed Personalized Ablation Lines (PersonAL) plan, which consists of iteratively targeting emergent high dominant frequency (HDF) regions, to identify the optimal ablation strategy. Localized ablations were connected to the closest non-conductive barrier to prevent recurrence of AF or atrial tachycardia. The first application of the HDF strategy had a success of >98% and isolated only 5-6% of the left atrial myocardium. In contrast, conventional ablation strategies targeting anatomical or structural substrate resulted in isolation of up to 20% of left atrial myocardium. After a second iteration of the HDF strategy, no further arrhythmia episode could be induced in any of the patient-specific models. The novel PersonAL in silico technology allows to unveil all AF-perpetuating areas and personalize ablation by leveraging atrial digital twins.

Incidence of ventricular arrhythmias after biventricular defibrillator replacement: impact on safety of downgrading from CRT-D to CRT-P.

Cardiac resynchronization therapy (CRT) reduces mortality and hospitalizations. It is debated whether CRT alone (CRT-P) or CRT plus defibrillator (CRT-D) is preferable, and still guidelines are not exhaustive. The aim of the study was to investigate whether to implant CRT-P or CRT-D in CRT-D patients who did not experience malignant arrhythmias at the moment of replacement. Out of 451 heart failure patients undergoing CRT-D according to guidelines, 103 (67±10 years, 80% men) underwent device replacement with CRT-D. Every 6 months patients underwent to clinical evaluation and device interrogation and episodes of ventricular arrhythmias (VA) stored. At baseline and before replacement echocardiogram was performed. Patients were defined responders if left ventricular (LV) end-systolic volume decreased ≥15% and super-responders if LV ejection fraction increased ≥40% or ≥50%. Mean follow-up was 75±24 months after implantation and 26±10 months after replacement. First VAs incidence per year did not decrease over time (P=0.619). Before replacement, 27 patients (26.2%, 15 responders/12 non-responders) experienced VA. After replacement, 8 patients (7.7%, 4 responders/4 non-responders) experienced VA for the first time. Super-responder condition was not associated with lower VA incidence before (0.499) and after (P=0.339) replacement. At multivariate analysis, age was the only independent predictor of electrical appropriate therapy after substitution (OR<inf>per year</inf>=1.17; 95% CI: 1.03-1.34; P=0.003). Freedom from VA before device replacement does not correlate with freedom from VA after replacement, so downgrade from CRT-D to CRT-P is not feasible at replacement, in particular in the elderlies, independently of responder and super-responder condition.

Heart rhythm assessment in elite endurance athletes: A better method?

IntroductionArrhythmias also occur among elite endurance athletes. Conventional diagnostic tools for assessment of arrhythmias suffer from limited availability and usability challenges, particularly under the demanding training conditions of an elite athlete. Among endurance athletes, there is a need for out-of-hospital monitoring to enhance detection of arrhythmias under conditions that are relevant and potentially provocative of underlying pathology. The Norwegian patch ECG247 Smart Heart Sensor has been developed to simplify the assessment of heart rhythm disorders. The current study aimed to evaluate the ECG247 Smart Heart Sensor function and usability in an elite athlete environment.MethodsA total of 13 professional cyclists from the UNO-X Pro Cycling Team were examined with the ECG247 Smart Heart Sensor during training camp in Spain, December 2021. All ECG data were analyzed by cardiologists at Sorlandet Hospital Arendal, Norway. The athletes also completed a brief questionnaire registering their training (from on-bike monitoring units) and provided self-assessment of usability parameters after the test.ResultsIn 8 of 13 athletes (69% male, age 23 ± 4 years), two test periods were performed with different ECG patches, resulting in a total of 21 tests with continuous ECG monitoring. Average total ECG test duration per athlete was 144 ± 47 h (89 ± 24 h/patch). Athletes performed an average of 15 ± 5 training h during each test. The ECG quality from all tests was considered satisfactory for rhythm analysis—also during exercise. The reported usability of the ECG247 Smart Heart Sensor was high, and no athletes reported trouble sleeping or training with the sensor. The automatic arrhythmia algorithm reported episodes of possible arrhythmias in 5 (24%) tests; 2 atrial flutter, 2 supraventricular tachycardia and 1 bradycardia (heart rate <30/min). Manual assessment by physicians verified the episode of bradycardia but revealed normal sinus rhythm in all other tests. No false negative events were identified in over 1,800 h of ECG collection.ConclusionThe ECG247 Smart Heart Sensor allowed for high quality ECG monitoring with high usability during intensive exercise in athletes.

Incidence, Associated Risk Factors, and Outcomes of Postoperative Arrhythmia After Upper Gastrointestinal Surgery

New-onset postoperative arrhythmia, which most often presents as postoperative atrial fibrillation (AF), is a frequent complication in patients undergoing visceral surgery of the upper gastrointestinal tract. Its relevance for patients' outcomes is unknown. To assess the incidence of arrhythmia after upper gastrointestinal surgery, its risk factors, and its short- and long-term implications for patient outcomes. This cohort study included 1210 patients who underwent surgery of the upper gastrointestinal tract (esophagus, stomach, or pancreas) at the University Medical Center Göttingen in Germany between January 2012 and December 2018. Follow-up was performed between February and May 2020. Patients were excluded if they had a preexisting cardiac arrhythmia or pacemaker. The incidence of atrial fibrillation (AF) was recorded in most cases of postoperative arrhythmia; therefore, the analysis focused on postoperative AF. A multivariable logistic regression model was used to assess associations between surgical complications and postoperative AF occurrence, with odds ratios and 95% CIs reported. A total of 1210 patients (median [IQR] age, 62 [19-90] years; 704 [58.2%] men) were enrolled in this study. Postoperative arrhythmia was recorded in 100 patients (8.3%). Among the different procedures, esophagectomy was associated with the highest incidence of postoperative AF (45.5% in complex esophageal resections and 17.1% in elective thoracoabdominal esophagectomies). The incidence of postoperative AF was associated with prolonged length of stay in the intensive care unit (23.4 days for patients with postoperative AF vs 5.9 days for those without; P < .001). Four factors were associated with the occurrence of postoperative AF: patients' age (OR, 1.06; 95% CI, 1.03-1.08; P < .001), intraoperative surgical complications (OR, 2.47; 95% CI, 1.29-4.74; P = .006), infections (OR, 2.23; 95% CI, 1.31-3.80; P = .003), and organ failure (OR, 4.01; 95% CI, 2.31-6.99; P < .001). In the multivariable analysis, postoperative AF (OR, 7.08; 95% CI, 2.75-18.23; P < .001) and sepsis (OR, 10.98; 95% CI, 3.91-30.81; P < .001) were associated with in-hospital mortality. At a median 19-month follow-up, 20 of 74 patients (27.0%) with postoperative AF developed recurring episodes of arrhythmia after discharge. This cohort study found that the postoperative AF was associated with an increased length of stay in the intensive care unit and in-hospital mortality in patients after upper gastrointestinal tract surgery. In addition, postoperative AF was associated with development of permanent or paroxysmal arrhythmia after discharge.

Advantages of using a portable cardiac monitor in outpatients with paroxysmal atrial fibrillation

Aim. To study the advantages of using a portable electrocardiographic (ECG) monitor in outpatients with paroxysmal atrial fibrillation (AF).Material and methods. We examined 88 patients (26 men, 62 women, mean age, 63 [57;68] years) with paroxysmal AF with an average frequency of arrhythmia episodes of 1,0 [0.3;3.75] per month. Forty three (49%) patients were included in the remote monitoring (RM) group using the ECG Dongle monitor, and 45 (51%) patients were included in the conventional monitoring (CM) group. Patients underwent scheduled examinations 2, 6 and 12 months after the start of therapy. Unscheduled consultations were carried out in case of AF recurrence. Patients from the RM group, using portable cardiac monitor, additionally self-registered ECG 1 time per week and in case of symptoms suggestive of AF. ECG strips were sent to the clinical investigator for analysis.Results. With the help of portable cardiac monitor, 2477 ECG strips were collected and analyzed: 2159 (87,2%) — sinus rhythm, 318 (12,8%) — AF and atypical atrial flutter. Forty four episodes of AF in 3 patients were asymptomatic. In addition, 211 (8,5%) sinus rhythm ECG strips were recorded by 13 patients with symptoms suggestive of AF. In the RM group, 7 (16%) patients were hospitalized due to recurrent AF, while in the CM group, 20 (44%) patients (p=0,004). The total number of emergency hospitalizations was 8 and 29 in the RM and CM groups, respectively. The number of patients who called an ambulance was significantly lower in the RM group: in the CM group, 37 calls for an ambulance were made by 22 patients, while in the RM group — 12 patients made 15 calls (p=0,044). The proportion of calls followed by hospitalization (40 vs 70%, p=0,043) was significantly lower in the RM group.Conclusion. Remote ECG monitoring using the ECG Dongle system is a useful way to monitor patients with paroxysmal AF, which make it possible to register asymptomatic AF episodes, differentiate the causes of palpitations, and significantly reduce the frequency of emergency calls and hospitalizations.

Incidence and Predictors of Cardiac Arrhythmias in Patients With COVID-19.

BackgroundCoronavirus disease 2019 (COVID-19) is a systemic disease caused by severe acute respiratory syndrome coronavirus 2. Arrhythmias are frequently associated with COVID-19 and could be the result of inflammation or hypoxia. This study aimed to define the incidence of arrhythmias in patients with COVID-19 and to correlate arrhythmias with pulmonary damage assessed by computed tomography (CT).MethodsAll consecutive patients with a COVID-19 diagnosis hospitalized at Universitair Ziekenhuis Brussel, Belgium, between March 2020 and May 2020, were screened. All included patients underwent a thorax CT scan and a CT severity score, a semiquantitative scoring system of pulmonary damage, was calculated. The primary endpoint was the arrhythmia occurrence during follow-up.ResultsIn this study, 100 patients were prospectively included. At a mean follow-up of 19.6 months, 25 patients with COVID-19 (25%) experienced 26 arrhythmic episodes, including atrial fibrillation in 17 patients, inappropriate sinus tachycardia in 7 patients, atrial flutter in 1 patient, and third-degree atrioventricular block in 1 patient. No ventricular arrhythmias were documented. Patients with COVID-19 with arrhythmias showed more often need for oxygen, higher oxygen maximum flow, longer QTc at admission, and worse damage at CT severity score. In univariate logistic regression analysis, significant predictors of the primary endpoint were: the need for oxygen therapy (odds ratio [OR] 4.59, 95% CI 1.44–14.67, p = 0.01) and CT severity score of pulmonary damage (OR per 1 point increase 1.25, 95% CI 1.11–1.4, p < 0.001).ConclusionsIn a consecutive cohort of patients with COVID-19 the incidence of cardiac arrhythmias was 25%. The need for oxygen therapy and CT severity score were predictors of arrhythmia occurrence during follow-up.

Fever following Covid-19 vaccination in subjects with Brugada syndrome: Incidence and management.

BackgroundFever is a potential side effect of the Covid‐19 vaccination. Patients with Brugada syndrome (BrS) have an increased risk of life‐threatening arrhythmias when experiencing fever. Prompt treatment with antipyretic drugs is suggested in these patients.Aim of the studyTo evaluate the incidence and management of fever within 48 h from Covid‐19 vaccination among BrS patients.MethodsOne hundred sixty‐three consecutive patients were enrolled in a prospective registry involving five European hospitals with a dedicated inherited disease ambulatory.ResultsThe mean age was 50 ± 14 years and 121 (75%) patients were male. Prevalence of Brugada electrocardiogram (ECG) pattern type‐1, ‐2, and ‐3 was 32%, 44%, and 24%, respectively. Twenty‐eight (17%) patients had an implantable cardioverter‐defibrillator (ICD). Fever occurred in 32 (19%) BrS patients after 16 ± 10 h from vaccination, with a peak of body temperature of 37.9° ± 0.5°. Patients with fever were younger (39 ± 13 vs. 48 ± 13 years, p = .04). No additional differences in terms of sex and cardiovascular risk factors were found between patients with fever and not. Twenty‐seven (84%) out of 32 patients experienced mild fever and five (16%) moderate fever. Pharmacological treatment with antipyretic drugs was required in 18 (56%) out of 32 patients and was associated with the resolution of symptoms. No patient required hospital admission and no arrhythmic episode was recorded in patients with ICD within 48 h after vaccination. No induced type 1 BrS ECG pattern and new ECG features were found among patients with moderate fever.ConclusionFever is a common side effect in BrS patients after the Covid‐19 vaccination. Careful evaluation of body temperature and prompt treatment with antipyretic drugs may be needed.

Capabilities of long-term ECG monitoring in patients with myocardial infarction: the longer, the better?

Background. In modern cardiology, 24-hour electrocardiogram (ECG) monitoring has a high diagnostic value, but this method has a number of disadvantages in detecting episodes of unstable life-threatening arrhythmias. An increase in ECG monitoring duration allows expanding the possibilities of diagnosing life-threatening arrhythmias.Objective. To study the possibilities of long-term ECG monitoring (48–120 hours) in the detection of life-threatening arrhythmic events and parameters of myocardial electrical instability in patients with ST-segment elevation myocardial infarction (STEMI).Design and methods. The study included 71 STEMI patients. All patients from the 4th day of STEMI underwent multi-day ECG monitoring in 3 leads using a telemetric ECG recording complex with an average recording duration of 90.4 ± 30.2 hours. The analysis of episodes of myocardial ischemia, rhythm and conduction disturbances, turbulence and heart rate variability, late ventricular potentials and dispersion of the QT interval within 5 days was carried out.Results. Long-term monitoring allowed detecting high-grade ventricular extrasystoles. Analysis of episodes of myocardial ischemia in the postinfarction period revealed significant differences in the data of 120h-ECG monitoring in comparison with 24h-ECG. Multiday ECG monitoring made it possible to detect dysfunction of the autonomic regulation of cardiac activity in patients 2 times more often.Conclusion. A comprehensive assessment of the possibilities of multi-day ECG monitoring is a promising direction in predicting severe arrhythmias in patients in the postinfarction period.

Effect Evaluation of Cardiac Resynchronization Therapy in Elderly Patients with Heart Failure by Ultrasound Image under QuickOpt Algorithm.

This research was aimed at analyzing the application value of echocardiography and QuickOpt algorithm in optimizing parameters of cardiac resynchronization therapy (CRT) in elderly patients with heart failure. 50 elderly patients who were diagnosed with chronic heart failure and underwent CRT were chosen as the research objects. According to the different optimization methods, the patients were divided into the echocardiography group and QuickOpt algorithm group, 25 cases in each group. The general data, optimized intervals, corresponding maximum aortic velocity time integrals (aVTIs), cardiac ultrasound indicators, and ventricular arrhythmia episodes of the patients in the two groups were analyzed. The results showed that there was no significant difference in the optimized sensed atrioventricular (SAV), paced atrioventricular (PAV), and ventricle to ventricle (VV) intervals and the corresponding aVTIs obtained by echocardiography and QuickOpt (P > 0.05). The consistency analysis revealed that the aVTIs in the SAV, PAV, and VV intervals presented a good consistency (P < 0.01), which were obtained by the echocardiography and QuickOpt functional optimization; the concordance correlation coefficient (CCC) in them was 96.16%, 98.03%, and 95.48%, respectively. The left ventricular ejection fraction (LVEF) showed an increasing trend over time in both groups, while the left ventricular end systolic volume (LVESV), left ventricular end diastolic volume (LVEDV), and morphological right ventricle (MRV) showed the downward trends over time, and the differences between two groups were not significant (P > 0.05). For the premature ventricular contraction (PVC) of ventricular arrhythmia episodes, there was no significant difference between the two groups in log (PVCs) and log (PVC runs) (P > 0.05). It was also found that both echocardiography and QuickOpt algorithm could improve the cardiac function of patients with heart failure significantly and reduce ventricular arrhythmia episodes and ventricular remodeling via optimized CRT; there was no difference in the improvement effect of the two optimization methods. However, echocardiography was inferior to QuickOpt algorithm in terms of time-consuming optimization in the intervals. This provided a reference for the clinical diagnosis and treatment of elderly patients with heart failure.

Frequency of cardioversions as an additional risk factor for stroke in atrial fibrillation – the FinCV-4 study

Background Patients with atrial fibrillation (AF) are selected for oral anticoagulation based on individual patient characteristics. There is little information on how clinical AF burden associates with the risk of ischaemic stroke or systemic embolism (SSE). The aim of this study was to explore the association of the frequency of cardioversions (CV) as a measure of clinical AF burden on the long-term SSE risk, with a focus on patients at intermediate stroke risk based on CHA2DS2-VASc score. For these patients, additional SSE risk stratification by assessing CV frequency may aid in the decision on whether to initiate oral anticoagulation. Methods This retrospective analysis of FinCV Study from years 2003–2010 included 2074 patients who were not using any oral anticoagulation (long term or temporary) after CVs and undergoing a total of 6534 CVs for AF from emergency departments of three hospitals. Two study groups were formed: high CV frequency (mean interval between CVs ≤12 months and low frequency (>12 months). Results A total of 107 SSEs occurred during a mean follow-up of 5.4 years. The event rates per 100 patient-years were 1.82 and 0.67 in high versus low CV frequency groups, respectively. After adjustment for CHA2DS2-VASc score, CV frequency independently predicted SSE (HR, 2.87 [95% CI, 1.47 to 5.64]; p = .002) at 3 years. Competing risk analysis also identified CV frequency (sHR, 2.70 [95% CI, 1.38–5.31]; p = .004) as an independent predictor for SSE. In patients with CHA2DS2-VASc score 1 and low CV frequency, the SSE risk was only 0.08 per 100 patient-years. Conclusions Frequency of CVs for symptomatic AF episodes provides additional information on stroke risk in AF patients with CHA2DS2-VASc score 1. Key messages This retrospective study offers a unique opportunity to observe the natural course of AF patients with infrequent episodes of clinical arrhythmia when they were not using OAC (before introduction of CHA2DS2-VASc score). Stroke or systemic embolism rate was very low (0.08 per 100 patient-years) in patients with one CHA2DS2-VASc point who visited the emergency room for cardioversion less than once a year. Frequency of cardioversions can be used for additional risk stratification in patients at intermediate risk of stroke based on CHA2DS2-VASc score.

Implantable cardioverter defibrillator in arrhythmogenic cardiomyopathy: which role for antitachycardia pacing?

Abstract Funding Acknowledgements Type of funding sources: None. Background Arrhythmogenic Cardiomyopathy (ACM) is an inherited cardiomyopathy characterized by ventricular arrhythmias and sudden cardiac death. Implantable cardioverter defibrillator (ICD) remains the only proven therapy to reduce mortality in ACM. Purpose The objective of this study was to identify characteristics of ventricular arrhythmias and treatment in patients with ACM. Method Retrospective analysis of the data of consecutives patients with confirmed diagnosis of ACM based on the proposed Padua Criteria, who underwent implantation of transvenous ICD from January 1992 and October 2021. The clinical data and information about appropriate and inappropriate ICD therapies were obtained from medical records with the review of the available intra-cardiac electrograms (EGMs). Results We enrolled 52 patients (69% males, mean age at implant 48.9 ±14.8 years), 27 (52%) were implanted for primary prevention, 25 (48%) for secondary prevention. After a median follow-up of 7.52 years [IQR: 4.37 - 12.0], 32 patients (61.5%) had 914 sustained episodes of ventricular arrhythmias (VA). 25 patients (48%) had 309 episodes of life-threatening arrhythmias (LT-VA), defined as sustained ventricular tachycardia ≥200 beats/min. In 29/32 patients (91%) ATP treated at least one episode of VA and in 14/25 (56%) at least one episode of LT-VA. Ventricular tachycardia (VT) detection was programmed at least 20 seconds, while VF detection was at least 7 seconds. Among patients with appropriate ICD activation, the first treated episode was a LT-VA in 50% of cases. Out of 914 VA episodes, 735 (80.4%) were treated with ATP and 179 (19.6%) with shocks. Considering LT-VA (cycle length 248 ± 25 ms), 201/309 (65%) and 108/309 (35%) episodes were treated with ATP and shocks, respectively. In 13 patients (25%) there was an inappropriate ICD activation, mostly caused by atrial fibrillation, while in 8 patients (15%) there was a complication needing reintervention (in 3 cases there was a loss of ventricular sensing dictating lead revision). Conclusions ACM patients are at risk of VA and LT-VA. The majority of VA at follow-up are monomorphic at rate &amp;lt;200 beats/minute, however the first treated VA episode is a LT-VA in half of cases. ATP is highly successful in terminating VT and even LT-VA, which questions the use of non-transvenous ICD in this young patient population. Nevertheless, transvenous ICDs are burdened by a relevant rate of lead complications which should be weighed in the choice of the ICD type.