2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia: Executive Summary

Clinical Significance of Supraventricular Tachycardia During Pregnancy in Healthy Women

BACKGROUND

Supraventricular tachycardias (SVT) are the most frequently encountered arrhythmias in pregnancy with unclear clinical significance.

OBJECTIVES

This study sought to report the prevalence, describe the management, and explore the association between SVT and adverse obstetric outcomes.

METHODS

Cohort study of primiparous and multiparous women without history of Cesarean section (CS), and with structurally normal hearts admitted in labor. The study group consisted of women with at least 1 SVT episode during pregnancy, and the control group was randomly selected in a 4:1 ratio.

RESULTS

Of 141,769 women meeting the inclusion criteria, SVT diagnosis was confirmed in 122. A total of 76 (age 33.2 ± 4.8 years) had at least 1 symptomatic and documented episode during pregnancy. In women with a known SVT diagnosis before pregnancy, medical therapy was not associated with a lower risk of SVT recurrence (OR: 1.07; 95% CI: 0.41-2.80). However, catheter ablation before pregnancy was associated with significantly lower risk of SVT recurrence (OR: 0.09; 95% CI: 0.04-0.23). Women with SVT during pregnancy had higher incidence of CS (39.5% vs 27.0%; P = 0.03), and preterm labor (PTL) (30.3% vs 8.6%; P < 0.001). Adjusting for age and parity, SVT during pregnancy was an independent predictor of CS (OR: 1.80; 95% CI: 1.03-3.10), particularly planned CS (OR: 2.89; 95% CI: 1.06-7.89) and PTL (OR: 4.37; 95% CI: 2.30-8.31).

CONCLUSIONS

SVT during pregnancy is associated with increased risk for CS and PTL in healthy women. History of SVT should be sought as early as preconception counseling, and a multidisciplinary approach is warranted for both prevention and management of SVT occurrence.

Gender and Age Differences in the Evaluation and Clinical Outcomes of Patients with Palpitations

BACKGROUND

Palpitations represent a common clinic complaint.

OBJECTIVE

To explore gender and age differences in the evaluation and outcomes of patients with palpitations in outpatient settings.

DESIGN/PARTICIPANTS

This is a retrospective observational study of 58,543 patients with no known structural cardiac disease or arrythmias presenting to primary care and cardiology clinics in an integrated health system in California with palpitations between January 2017 and December 2021. The primary and secondary endpoints were hospitalization for arrhythmia and all-cause mortality at 1 year. Multivariable logistic regression models evaluated the association between gender, age, and outcomes.

RESULTS

Men and women were equally as likely to be started on beta-blockers (adjusted OR 0.96, 95% CI 0.90-1.02) and evaluated with electrocardiograms (adjusted OR 0.95, 95% CI 0.90-1.01) and cardiac monitors (adjusted OR 1.04, 95% CI 0.99-1.08). Patients who completed Holter or event monitors had a lower rate of hospitalization for cardiovascular disease at 1 year than those without (2.3% vs. 2.7%, p = 0.001). At 1 year, women had a lower risk of all-cause mortality (adjusted OR 0.47, 95% CI 0.35-0.64) and hospitalization for atrial fibrillation (adjusted OR 0.47, 95% CI 0.30-0.72) and arrhythmias (adjusted OR 0.73, 95% CI 0.58-0.91) compared to men. Among older women and men (≥ 80 years), there was no significant difference in 1-year all-cause mortality (adjusted OR 0.57, 95% CI 0.29-1.12), hospitalization for atrial fibrillation (adjusted OR 0.58, 95% CI 0.17-1.97), or arrhythmias (adjusted OR 1.15, 95% CI 0.12-11.07).

CONCLUSIONS

There were no gender differences in referrals for cardiac monitoring or prescriptions for beta-blockers. Women had a better prognosis with a lower risk of hospitalization for arrhythmias and death at 1 year compared to men. However, 1-year risks for mortality and hospitalization for arrythmias among older women were comparable to those of older men, underscoring the importance of considering age and gender in managing patients with palpitations.

The Safety and Feasibility of Pulsed-Field Ablation in Atrioventricular Nodal Re-Entrant Tachycardia: First-in-Human Pilot Trial

BACKGROUND

The incidence of atrioventricular conduction system damage during the catheter ablation procedure has long been a safety concern in patients with atrioventricular nodal re-entrant tachycardia (AVNRT). Pulsed-field ablation (PFA) with high tissue selectivity is a promising technique to address this problem in patients with AVNRT.

OBJECTIVES

This study aimed to evaluate the safety and feasibility of PFA in patients with AVNRT.

METHODS

This was an investigator-initiated, single-center, single-arm, prospective study performed in West China Hospital, Sichuan University. Patients diagnosed with AVNRT by electrophysiological examination were included and treated using PFA. The primary outcome was the ability to achieve acute ablation success. The secondary outcomes were ablation success after 6 months and safety incidents reported.

RESULTS

A total of 30 patients with AVNRT with a mean age of 47.9 ± 13.9 years were included and underwent PFA. Acute ablation success was achieved in all patients. The skin-to-skin procedure time was 109.1 ± 32.1 minutes, and fluoroscopy time was 4.1 ± 0.9 minutes. A median of 8 (range: 6.5 to 11.0) PFA applications were delivered. The average distance of the closest ablation site to the His bundle was 6.5 ± 2.5 mm, with a minimum distance of 2.0 mm. All patients maintained sinus rhythm after 6 months. No adverse events occurred in any patient during the ablation or the 6-month follow-up.

CONCLUSIONS

PFA showed favorable feasibility and safety in patients with AVNRT in this pilot study. Further study with larger population and longer follow-up time is warranted to verify the results.

Adenosine response and failure to convert paroxysmal supraventricular tachycardia in the emergency department

BACKGROUND AND IMPORTANCE

Although adenosine is the recommended first-line therapy for patients with paroxysmal supraventricular tachycardia (SVT), it may fail to restore normal sinus rhythm. The factors associated with this failure remain unclear.

OBJECTIVE

To assess the response rate to adenosine and identify the factors causing adenosine failure in the management of paroxysmal SVT.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective study was conducted on adult patients diagnosed with paroxysmal SVT and treated with adenosine in the emergency departments of two large tertiary hospitals between June 2015 and June 2021.

OUTCOME MEASURE AND ANALYSIS

The primary outcome of the study was the patient response to adenosine, defined as the restoration of sinus rhythm documented in the patients' files. Backward-stepwise multivariate logistic regression was used to examine the predictors of adenosine failure based on the overall response to adenosine therapy.

MAIN RESULTS

A total of 404 patients, with a mean age of 49 (SD 15) years and a BMI of 32 (SD 8) kg/m 2 , and treated with adenosine for paroxysmal SVT, were included. Sixty-nine percent of patients were women. The overall response rate to any adenosine dose was 86% (n = 347). The baseline heart rate did not significantly differ between adenosine responders and non-responders (179.6 ± 23.1 vs. 183.2 ± 23.4). An association was observed between the history of paroxysmal SVT and successful response to adenosine (odds ratio = 2.08; 95% confidence interval 1.05-4.11).

CONCLUSION

The findings of this retrospective study suggested that the use of adenosine restored normal sinus rhythm in 86% of patients with paroxysmal SVT. Furthermore, a history of paroxysmal SVT and older age were associated with an increased chance of adenosine success.

Hypomagnesemia Caused by Chronic Use of Over-the-Counter Proton Pump Inhibitor as a Possible Cause of Supraventricular Tachycardia

Magnesium is an important co-factor that helps regulates the movement of ions through voltage-mediated channels within myocardial tissues by the membrane sodium-potassium pump, and its deficiency can reduce the pump's activity, leading to partial depolarization and changes in the activity of many potential-dependent membrane channels leading to arrhythmias. In this case report, we are looking to establish the direct relationship between hypomagnesemia caused by proton pump inhibitors (PPIs), which could lead to cardiac arrhythmias. Here, we present a 45-year-old Hispanic female, with a known past medical history of supraventricular tachycardia (SVT), hiatal hernia on proton pump inhibitor (PPI), and chronic smoking, who presented to the emergency department complaining of dizziness and palpitations that started two hours prior arrival to the hospital. At triage, the patient was found to have a heart rate of 190 beats per minute (bpm), and an electrocardiogram (EKG) revealed supraventricular tachycardia with a heart rate of 185 bpm. During the review of this case, no other confounding factors besides hypomagnesemia were noted, leaving this one to be the most likely cause of the arrhythmia. Patients on long-term PPI therapy are at higher risk of developing hypomagnesemia, which could lead to cardiac arrhythmia.

Combination of Slow Pathway Late Activation Maps and Voltage Gradient Maps in Guidance of Atrioventricular Nodal Reentry Tachycardia Cryoablation

BACKGROUND

The optimal strategy for electroanatomic mapping-guided cryoablation of atrioventricular nodal reentry tachycardia (AVNRT) remains unclear.

OBJECTIVE

To investigate the effectiveness of slow pathway late activation mapping (SPLAM) and voltage gradient mapping for AVNRT cryoablation.

METHODS

From June 2020 to February 2022, all consecutive patients with AVNRT underwent SPLAM to define the wave collision point and voltage gradient mapping to define the low voltage bridge (LVB). Conventional procedures performed from August 2018 to May 2020 served as control.

RESULTS

The study and control groups comprised 36 (aged 16.5±8.2 years) and 37 patients (aged 15.5±7.3 years), respectively. Total procedural times were comparable, and acute success rates were 100% in both groups. Compared to controls, number of cryomapping attempts (median 3 vs. 5, p=0.012) and cryoablation applications (median 1 vs. 2, p<0.001) were significantly lower in the study group. At a median follow-up of 14.6 and 18.3 months, recurrence rates were 5.6% (2 patients) and 10.8% (4 patients) in the study and control groups (p=0.402), respectively. Mapping of Koch's triangle took 11.8±3.6 min, in which 1562±581 points were collected. In SPLAM, wave collision points were defined and compatible with the final successful lesion sites in all patients, including those with multiple slow pathways. LVB could not be defined in 6 patients (16.7%), and LVB was not compatible with the final successful lesion in another 6 (16.7%).

CONCLUSIONS

For AVNRT cryoablation, SPLAM could effectively guide the localization of slow pathway ablation sites and was particularly beneficial in patients with multiple slow pathways.

Control of Heart Rate in Infant and Child Tachyarrhythmia With Reduced Cardiac Function Using Landiolol (HEARTFUL) - Results of a Prospective, Multicenter, Uncontrolled Clinical Study

BACKGROUND

The prospective Control of HEART rate in inFant and child tachyarrhythmia with reduced cardiac function Using Landiolol (HEARTFUL) study investigated the effectiveness and safety of landiolol, a short-acting β₁ selective blocker, in children.Methods and Results: Twenty-five inpatients aged ≥3 months to <15 years who developed supraventricular tachyarrhythmias (atrial fibrillation, atrial flutter, supraventricular tachycardia, and inappropriate sinus tachycardia) were treated with landiolol. The primary endpoint, the percent of patients with a reduction in heart rate ≥20% from the initial rate of tachycardia, or termination of tachycardia at 2 h after starting landiolol, was achieved in 12/25 patients (48.0%; 95% CI 28.4-67.6), which exceeded the predetermined threshold (38.0%). At 2 h after starting landiolol administration, heart rate had decreased by ≥20% in 45.8% (11/24) and recovery to sinus rhythm was achieved in 40.0% (6/15) of the patients. Adverse reactions (ARs) occurred in 24.0% (6/25) of patients, and the study was discontinued in 4.0% (1/25) of the patients; however, none of these ARs were considered serious. The most common AR was hypotension (20.0% [5/25] of patients).

CONCLUSIONS

The HEARTFUL study has demonstrated the efficacy of landiolol, by reducing heart rate or terminating tachycardia, in pediatric patients with supraventricular tachyarrhythmias. Although serious ARs and concerns were not identified in this study, physicians should be always cautious of circulatory collapse due to hypotension.

Antiarrhythmic Drug Therapy in the Treatment of Acute and Chronic Atrial Flutter

In the present article, we will focus on the pharmacologic treatment of atrial flutter aimed either at restoring/maintaining sinus rhythm or controlling the ventricular response during tachyarrhythmia. To provide a comprehensive description we will start discussing the electroanatomic substrate underlying the development of atrial flutter and the complex relationship with atrial fibrillation. We will then describe the available drugs for the treatment of atrial flutter on the bases of their electrophysiological effects and data from available clinical studies. We will conclude by discussing the general principles of rhythm and rate control treatment during atrial flutter.

Arrhythmias and Heart Failure in Pregnancy: A Dialogue on Multidisciplinary Collaboration

The prevalence of CVD in pregnant people is estimated to be around 1 to 4%, and it is imperative that clinicians that care for obstetric patients can promptly and accurately diagnose and manage common cardiovascular conditions as well as understand when to promptly refer to a high-risk obstetrics team for a multidisciplinary approach for managing more complex patients. In pregnant patients with CVD, arrhythmias and heart failure (HF) are the most common complications that arise. The difficulty in the management of these patients arises from variable degrees of severity of both arrhythmia and heart failure presentation. For example, arrhythmia-based complications in pregnancy can range from isolated premature ventricular contractions to life-threatening arrhythmias such as sustained ventricular tachycardia. HF also has variable manifestations in pregnant patients ranging from mild left ventricular impairment to patients with advanced heart failure with acute decompensated HF. In high-risk patients, a collaboration between the general obstetrics, maternal-fetal medicine, and cardiovascular teams (which may include cardio-obstetrics, electrophysiology, adult congenital, or advanced HF)—physicians, nurses and allied professionals—can provide the multidisciplinary approach necessary to properly risk-stratify these women and provide appropriate management to improve outcomes.

Inappropriate Sinus Tachycardia: Etiology, Pathophysiology, and Management: JACC Review Topic of the Week

Inappropriate sinus tachycardia (IST) is a clinical syndrome that generally affects young patients and is associated with distressing symptoms. Although the most common symptom is palpitations, it can be accompanied by a myriad of symptoms, including anxiety, dizziness, presyncope, and syncope. The pathogenesis of IST is not well understood and considered multifactorial, with autonomic dysfunction being the central abnormality. IST is a diagnosis of exclusion. Management presents a clinical challenge. The overall efficacy of lifestyle modifications and medical therapy may be limited. Recent advances in catheter and surgical sinus node sparing ablation techniques have led to improvement in outcomes. In addition, increased focus has led to development of multimodality team-based interventions to improve outcomes in this group of patients. In this review, we discuss the mechanistic basis of IST, review current approaches to diagnosis, and outline contemporary therapeutic approaches.

An Evaluation of Prehospital Adenosine Use

BACKGROUND

Adenosine has been safely used by paramedics for the treatment of stable supraventricular tachycardia since the mid-1990s. However, there continues to be variability in paramedics' ability to identify appropriate indications for adenosine administration. As the first of a planned series of studies aimed at improving the accuracy of SVT diagnosis and successful administration of adenosine by paramedics, this study details the current usage patterns of adenosine by paramedics.

METHODS

This cross-sectional retrospective study investigated adenosine use within a large northeast EMS region from January 1, 2019, through September 30, 2021. Excluding pediatric and duplicate case reports, we created a dataset containing patient age, sex, and vital signs before, during, and after adenosine administration; intravenous line location; and coded medical history from paramedic narrative documentation, including a history of atrial fibrillation, suspected arrhythmia diagnosis, and effect of adenosine. In cases with available prehospital electrocardiograms (EKGs) for review, two physicians independently coded the arrhythmia diagnosis and outcome of adenosine administration. Statistical analysis included interrater reliability with Cohen's kappa statistic.

RESULTS

One hundred eighty-three cases were included for final analysis, 84 did not have a documented EKG for review. Categorization of presenting rhythms in these cases occurred by a physician reviewing EMS narrative and documentation. Forty of these 84 cases (48%) were adjudicated as SVT likely, 32 (38%) as SVT unlikely and 12 (14%) as uncategorized due to lack of supporting documentation. Of the 99 cases with EKGs available to review, there was substantial agreement of arrhythmia diagnosis interpretation between physician reviewers (Cohen's kappa 0.77-1.0); 54 cases were adjudicated as SVT by two physician reviewers. Other identified cardiac rhythms included atrial fibrillation (16), sinus tachycardia (11), and ventricular tachycardia (2). Adenosine cardioversion occurred in 47 of the 99 cases with EKGs available for physician review (47.5%). Adenosine cardioversion was also deemed to occur in 87% (47/54) of cases when the EKG rhythm was physician adjudicated SVT.

CONCLUSIONS

This study supports the use of adenosine as a prehospital treatment for SVT while highlighting the need for continued efforts to improve paramedics' identification and management of tachyarrhythmias.

Discrimination of atypical atrioventricular nodal reentrant tachycardia from atrial tachycardia by the V-A-A-V response

INTRODUCTION

The electrophysiological discrimination between fast-slow (F/S-) atrioventricular (AV) nodal reentrant tachycardia (NRT) and atrial tachycardia (AT) originating from the interatrial septum remains challenging. While a V-A-A-V response may occur immediately after ventricular induction or entrainment of either tachycardia, the electrophysiological dissimilarities in that response between the two tachycardias remain unclear. The purpose of this study was to identify a diagnostic indicator discriminating F/S-AVNRT from AT by examining the difference in the V-A-A-V response between the two tachycardias.

METHODS

This retrospective study included 17 patients with F/S-AVNRT [7 with common-form F/S-AVNRT using a typical slow pathway (SP) and 10 with superior type F/S-AVNRT using a superior SP] and 10 patients with reentrant AT. All 27 patients presented with long RP supraventricular tachycardia and an initial V-A-A-V response upon ventricular induction or entrainment. The V-A-A-V response in patients with F/S-AVNRT was due to dual atrial responses. We measured the interval between the first (A1) and second atrial electrogram (A2) of V-A-A-V and calculated ΔAA by subtracting A1-A2 from the tachycardia cycle length.

RESULTS

V-A-A-V responses were observed most often upon ventricular induction of F/S-AVNRT (6±5 times) as well as AT (6±6 times; P = 0.87). The V-A-A-V response upon ventricular entrainment was observed in a single patient with F/S-AVNRT versus 10 all patients with AT (P<0.001). ΔAA ranged between -80 and 228 ms in F/S-AVNRT and between -184 and 26 ms in AT. A ΔAA >26 ms predicted a diagnosis of F/S-AVNRT with a 76% sensitivity and 100% specificity, while a ΔAA ←80 ms predicted a diagnosis of AT with a 50% sensitivity and 100% specificity.

CONCLUSIONS

ΔAA is a useful, confirmatory, diagnostic indicator of F/S-AVNRT versus AT associated with the V-A-A-V response. This article is protected by copyright. All rights reserved.

The feasibility of using remote magnetic navigation system as the primary technological training tool for novice cardiac electrophysiology operators in the catheter ablation of left-sided accessory pathway

BACKGROUND

For novice operators, mastering catheter ablation of left-sided accessory pathway (LSAP) in a short duration of time without compromising efficacy and safety remains a challenge. In this study an attempt to shorten the learning curve by using robotics via a remote magnetic navigation (RMN) system was performed.

METHODS

Novice physician fellows without prior catheter ablation experience initiated their process of learning LSAP ablation using the Niobe™ RMN system. Their procedure parameters were recorded and compared with experienced operators using RMN and manual catheter navigation (MCN).

RESULTS

Novice operators quickly shortened the total procedure time after their first five procedures. In subsequent procedures, no significant difference in procedure time, fluoroscopy exposure or ablation time was observed between novice and experienced RMN operators. When compared to MCN operators, novice operators avoided excessive radiation exposure beginning with their first RMN procedure, while lower fluoroscopy doses were noted after five procedures. It was observed that procedure parameters did not differ significantly according to LSAP location.

CONCLUSION

The RMN system is a practical and easy to use tool for novice electrophysiology operators to quickly master LSAP ablation, without compromising efficacy or safety. Additionally, when compared to MCN it also protects the operators and patients from excessive radiation exposure during the procedure.

Beta blockers for the treatment of arrhythmias: Bisoprolol - a systematic review

OBJECTIVES

Beta blockers have long been successfully used for the treatment of both supraventricular and ventricular arrhythmias. However, differences exist between their chemical structure, pharmacokinetic and pharmacodynamic properties (absorption, bioavailability, metabolism, hydrophilic or lipophilic character, selective or non-selective nature, the presence or absence of intrinsic sympathomimetic activity), which may confer different antiarrhythmic properties to different beta blockers. The aim of this study was to analyze the current existing evidence for bisoprolol for the treatment of both supraventricular and ventricular arrhythmias.

MATERIAL AND METHODS

Using the keywords "bisoprolol" and "arrhythmias" or "atrial fibrillation" or "ventricular tachycardia" or "premature ventricular complexes" or "ventricular fibrillation", the Medline database was searched for articles in English or French until April 2020 assessing the role of bisoprolol in the treatment of arrhythmias. Data was then analyzed according to the type of arrhythmia treated and the quality of evidence using the GRADE approach.

RESULTS

A total of 325 studies were identified, of which 28 were considered relevant to the current topic. Among these studies, 19 assessed the role of bisoprolol for the treatment of supraventricular arrhythmias, 8 its role in treating ventricular arrhythmias and 1 its role in supraventricular and ventricular arrhythmias. The quality of evidence varied from low (7 studies) to high (5 studies).

CONCLUSION

Current evidence exists supporting the use of bisoprolol for the treatment of supraventricular arrhythmias, especially for rate control during atrial fibrillation. Evidence also exists for its efficacy in the treatment of ventricular arrhythmias, both in primary and in secondary prevention.

Arrhythmias in Pregnancy

Increasing maternal mortality and incidence of arrhythmias in pregnancy have been noted over the past 2 decades in the United States. Pregnancy is associated with a greater risk of arrhythmias, and patients with a history of arrhythmias are at significant risk of arrhythmia recurrence during pregnancy. The incidence of atrial fibrillation in pregnancy is rising. This review discusses the management of tachyarrhythmias and bradyarrhythmias in pregnancy, including management of cardiac arrest. Management of fetal arrhythmias are also reviewed. For patients without structural heart disease, β-blocker therapy, especially propranolol and metoprolol, and antiarrhythmic drugs, such as flecainide and sotalol, can be safely used to treat tachyarrhythmias. As a last resort, catheter ablation with minimal fluoroscopy can be performed. Device implantation can be safely performed with minimal fluoroscopy and under echocardiographic or ultrasound guidance in patients with clear indications for devices during pregnancy. Because of rising maternal mortality in the United States, which is partly driven by increasing maternal age and comorbidities, a multidisciplinary and/or integrative approach to arrhythmia management from the prepartum to the postpartum period is needed.

Tachycardia-induced cardiomyopathy in three consecutive pregnancies

Tachycardia-induced cardiomyopathy is rare during pregnancy and is reversible when the underlying arrhythmia is effectively treated. Management can be complex due to the risks of antiarrhythmic medications and cardiac interventions on the developing fetus. The care requires a well-coordinated multidisciplinary team of cardiologists, electrophysiologists, and maternal-fetal specialists. In this report, we describe a case of recurrent atrial tachycardia-induced cardiomyopathy in pregnancy.

Management of Wolff-Parkinson-White syndrome in a patient with peripartum cardiomyopathy

Wolf-Parkinson-White (WPW) syndrome is a congenital heart condition in which the atrioventricular (AV) node is bypassed by an accessory pathway that connects the atria and ventricle directly along with symptoms of syncope or palpitations. WPW syndrome in patients with a history of peripartum cardiomyopathy (pregnancy-related cardiomyopathy) is associated with a high risk of morbidity and mortality secondary to failure of the pump and the conduction system of the heart. Management of these cases deals with arrhythmia and systolic heart failure, which becomes more challenging in pregnant patients as it requires treatment methods that minimize risks to the fetus. We report a case of a young female patient with WPW syndrome and peripartum cardiomyopathy presenting with symptomatic arrhythmias (tachycardia).

The correlation of 30- and 90-day mortality rates with Hs-troponin I values measured in patients diagnosed with paroxysmal supraventricular tachycardia in emergency service

Background:

This study aims to determine the relationship between troponin levels and 30- and 90-day mortality rates in patients who applied to emergency service with paroxysmal supraventricular tachycardia.

Materials and methods:

The data of our study were obtained from the retrospective screening of the files of 321 patients who applied to the emergency department between 1 January 2015 and 31 December 2016 with International Classification of Diseases diagnosis with I47.1 (supraventricular tachycardia). Unstable patients, patients under 18 years, and patients with comorbidities that could increase troponin levels did not participate in the study. A total of 159 patients diagnosed with paroxysmal supraventricular tachycardia were included in the study. These patients’ files were examined, and their examination and anamnesis information at the time of admission to hospital, demographic characteristics, and applied treatments were analyzed. The 30- and 90-day mortality rates of the patients were examined.

Results:

The study was carried out with 159 patients. Troponin was positive in 25 (15.7%) cases, while it was negative in 134 (84.3%) cases. There was no significant difference between the two groups in terms of 30- and 90-day mortality rates. Coronary artery disease was found to be higher in patients with positive troponin than patients with negative troponin.

Conclusion:

No significant difference was found between patients with positive troponin values compared to patients with negative troponin values in terms of 30- and 90-day mortality rates. We believe that prospective observational studies or large-scale retrospective studies will better elucidate this issue.

Stereotactic Radiosurgery for Atrioventricular Node Ablation in Swine: A Study on Efficacy and Dosimetric Evaluation of Organs at Risk

Introduction Stereotactic radiosurgery (SRS) delivered to arrhythmogenic foci within the heart is a promising treatment modality. We dosimetrically evaluated the radiation dose to the organs at risk of four swine that were successfully treated with linear-accelerator-based SRS for atrioventricular (AV) node ablation. Materials and methods Single-chamber pacemakers were implanted in four large white breed swine. Cardiac computed tomography simulation scans were performed to localize the AV node and organs at risk. SRS (35-40 Gy) was delivered to the AV node, and the pigs were followed up with pacemaker interrogations. One-sample t-tests were used to evaluate Dmax of great vessels, esophagus, and chest wall as compared to known normal tissue constraints as per RTOG 0631 and AAPM Task Group 101. Results All pigs had disturbances of AV conduction with progressive transition into complete heart block. Macroscopic and microscopic evaluation showed fibrosis in the AV node but did not reveal any changes in non-nodal cardiac tissue or vessels. The mean Dmax±SD (p-value) of the chest wall (14.7±3.3 (0.02)), esophagus (10.7±1.1 (<0.01)) superior vena cava (3.3±4.1 (<0.01)), right pulmonary artery (16.1±6.4 (<0.01)), right pulmonary vein (15.7± 5 (<0.01)), left pulmonary artery (11.1±1.7 (<0.01)) and left pulmonary vein (14.1±2.6 (<0.01)), and the inferior vena cava (33.68±1.6 (0.026)) were significantly below the normal tissue constraint cutoffs. Mean±SD (p-value) of the ascending aorta (19.4±16.1 (0.12)) was not significantly different than normal tissue constraint cutoffs. One swine model treated at 40 Gy had small area of hotspot in the ascending aorta (40.65 (0.4 cc)). Conclusion We have demonstrated in our swine models that SRS using 35-40 Gy can be done without exceeding known human normal tissue constraints to the chest wall, esophagus, and great vessels.

Supraventricular Tachycardia in Pregnancy: Gestational and Labor Differences in Treatment

Supraventricular tachycardia (SVT) is a tachyarrhythmia characterized by a heart rate above 120 beats per minute (BPM). Patients with SVT exhibit the following symptoms: palpitations, shortness of breath, chest pain, hemodynamic instability, or possibly asymptomatic. The increase in cardiac output and the increase in resting heart rate during pregnancy predispose pregnant women to SVT. The management of SVT in pregnancy, although remarkably similar, varies slightly based on the trimester of pregnancy. Atenolol and verapamil are effective methods of treating SVT, which can be used during the second and third trimesters. Both medications are contraindicated in the first trimester. At the same time, intravenous adenosine can be used in all three trimesters, including labor. Electrical cardioversion is an effective treatment method for hemodynamically unstable or drug-refractory patients, which has proven to be safe in all three trimesters, including labor but can result in pre-term labor in the third trimester. Non-fluoroscopic ablation proved to be the only treatment method that definitively resolved SVT without recurrence.

The clinical impact of paroxysmal arrhythmias on the hospital outcomes of patients admitted with cirrhosis: propensity score matched analysis of 2011-2017 US hospitals

BACKGROUND

We evaluate the effects of paroxysmal arrhythmia on the hospital outcomes of patients admitted with cirrhosis.

RESEARCH DESIGN AND METHODS

2011-2017 National Inpatient Sample was used to isolate patients with decompensated/compensated cirrhosis, stratified by paroxysmal arrhythmia (supraventricular: PSVT and ventricular: PVT). The cohorts were matched using propensity-score matching and compared to mortality, length of stay, cost, and cardiac complications (cardioversion, cardiogenic shock, cardiac arrest, and ventricular fibrillation).

RESULTS

In compensated cirrhosis, 2,453 had PSVT with matched controls; 5,274 had PVT with matched controls. Those with PSVT had higher mortality (aOR 1.55 95%CI 1.23-1.95) and higher rates of cardioversion and cardiogenic shock; likewise, those with PVT had higher mortality (aOR 2.41 95%CI 2.09-2.78) and higher rates of all complications. In decompensated cirrhosis, 1,598 had PSVT with matched controls; 4,178 had PVT with matched controls. Those with PSVT had higher mortality (aOR 1.57 95%CI 1.28-1.93) and higher rates of cardioversion, cardiogenic shock, cardiac arrest; those with PVT had higher mortality (aOR 2.25 95%CI 1.98-2.56) and higher rates of all complications.

CONCLUSION

The findings from this study show that in either decompensated or compensated cohort, those with paroxysmal arrhythmias are at a higher risk of in-hospital mortality and adverse cardiac outcomes.

Radiofrequency Catheter Ablation of Supraventricular Tachycardia in Patients With Pulmonary Hypertension: Feasibility and Long-Term Outcome

Background

Supraventricular tachycardia (SVT) occurs commonly and is strongly correlated with clinical deterioration in patients with pulmonary hypertension (PH). This study aimed to investigate the feasibility and long-term outcome of radiofrequency catheter ablation (RFCA) in PH patients with SVT.

Materials and Methods

Consecutive PH patients with SVT who were scheduled to undergo electrophysiological study and RFCA between September 2010 and July 2019 were included. The acute results and long-term success of RFCA were assessed after the procedure.

Results

In total, 71 PH patients with 76 episodes of SVT were analyzed. Cavotricuspid isthmus-dependent atrial flutter (n = 33, 43.5%) was the most common SVT type, followed by atrioventricular nodal reentrant tachycardia (n = 16, 21.1%). Of the 71 patients, 60 (84.5%) underwent successful electrophysiological study and were subsequently treated by RFCA. Among them, acute sinus rhythm was restored in 54 (90.0%) patients, and procedure-related complications were observed in 4 (6.7%) patients. Univariate logistic regression analysis showed that cavotricuspid isthmus-independent atrial flutter [odds ratio (OR) 25.00, 95% confidence interval (CI) 3.45–180.98, p = 0.001] and wider pulmonary artery diameter (OR 1.19, 95% CI 1.03–1.38; p = 0.016) were associated with RFCA failure. During a median follow-up of 36 (range, 3–108) months, 7 patients with atrial flutter experienced recurrence, yielding a 78.3% 3-year success rate for RFCA treatment.

Conclusion

The findings suggest that RFCA of SVT in PH patients is feasible and has a good long-term success rate. Cavotricuspid isthmus-independent atrial flutter and a wider PAD could increase the risk for ablation failure.

Evaluation of cardiac functions after catheter ablation of atrioventricular nodal reentrant tachycardia

Background/aim

Radiofrequency catheter ablation (RFA) is the most effective method of supraventricular tachycardia therapy. Recurrent supraventricular tachycardia causes systolic dysfunction and dilated cardiomyopathy. The aim of this study was to evaluate the long-term alterations of atrial and ventricular functions after RFAof typical atrioventricular nodal reentrant tachycardia (AVNRT).

Materials and methods

This cross-sectional study included 55 consecutive patients with symptomatic drug-resistant AVNRT who had had an invasive electrophysiology study and RFA. Speckle-tracking–based echocardiographic assessment was performed shortly before and 1 year after the operation. Left ventricle (LV) and right ventricle (RV) peak systolic strain (PSS) and atrial strain measurements were performed.

Results

RFA successfully eliminatedtachyarrhythmia in all patients. LV apical 4-chamber PSS –20.8% (–24.7 to –16.0) vs. –22.8% (–26.6 to –17.0, P < 0.001), LV apical 2-chamber PSS –21.5% (–26.8 to –10.1) vs. –22.0% (–27.8 to –13.7, P < 0.001), LV global PSS –20.4% (–26.4 to –14.4) vs. –23.0% (–27.1 to –2.3, P < 0.001), RV global PSS –26.0% (–30.0 to –18.0) vs. –26.5% (–32.1 to –19.7, P < 0.001), and peak left atrial longitudinal strain 41.0% (19.0–71.8) vs. 54.0% (25.6–82.0, P < 0.001) were significantly improved 1 year after RFA.

Conclusion

RFA of AVNRT not only provides relief of palpitations but also improves cardiac functions.

Long-Term Outcomes of Near-Zero Radiation Ablation of Paroxysmal Supraventricular Tachycardia: A Comparison With Fluoroscopy-Guided Approach

OBJECTIVES

This study aimed to assess the long-term outcomes of minimally fluoroscopic approach (MFA) compared with conventional fluoroscopic ablation (ConvA) in terms of recurrences of arrhythmia and long-term complications.

BACKGROUND

Catheter ablation (CA) of supraventricular tachycardia (SVT) with an MFA, under the guidance of electroanatomic mapping (EAM) systems, results in a significant reduction in exposure to ionizing radiations without impairing acute procedural success and complication rate. However, data regarding long-term outcomes of MFA compared with ConvA are lacking.

METHODS

This is a retrospective observational study. All patients undergoing MFA CA of SVT (atrioventricular nodal re-entrant tachycardia and atrioventricular re-entrant tachycardia) between 2010 and 2015 were enrolled and were compared with matched subjects (1 MFA: 2 ConvA) undergoing ConvA during the same period. The 2 co-primary outcomes were recurrence of arrhythmias and long-term complications.

RESULTS

Six-hundred eighteen patients (mean age 38 ± 15 years, 60% female) were enrolled. MFA included 206 patients, whereas 412 were treated with ConvA. Acute success (99% vs. 97%; p = 0.10) and acute complications (2.4% vs. 5.3%; p = 0.14) were similar in the 2 groups. During a median follow-up of 4.4 years, 5.9% of patients experienced recurrence of arrhythmias. At multivariate analysis, ConvA (hazard ratio [HR]: 3.03) and procedural success (HR: 0.10) were independently associated with recurrence of arrhythmias. Late complications (i.e., advance atrioventricular block and need for pacemaker implantation) occurred more frequently in ConvA (3.4% vs. 0.5%; p = 0.03) compared with MFA.

CONCLUSIONS

CA guided by EAM systems with MFA provided better long-term results and reduced risk of complications compared with ConvA.

European Resuscitation Council Guidelines 2021: Adult advanced life support

These European Resuscitation Council Advanced Life Support guidelines, are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the prevention of and ALS treatments for both in-hospital cardiac arrest and out-of-hospital cardiac arrest.

Enhanced detection of cardiac arrhythmias utilizing 14-day continuous ECG patch monitoring

BACKGROUND

To evaluate the performance of a single‑lead, 14-day continuous electrocardiogram (ECG) patch for the detection of arrhythmias compared to conventional 24-h monitoring.

METHODS

This prospective clinical trial enrolled patients suspected of arrhythmias but not diagnosed by 12‑lead ECGs. Each patient underwent a 24-h Holter and 14-day ECG patch simultaneously. Seven types of arrhythmias were classified: supraventricular tachycardia (SVT, repetitive atrial beats >4 beats), irregular SVT without P wave (>4 beats), AF/AFL (irregular SVT without P wave ≥30 s), pause ≥3 s, atrioventricular block (AVB; Mobitz type II, third-degree, two to one or high degree AVB), ventricular tachycardia (VT), and polymorphic VT.

RESULTS

A total of 158 patients were recruited (mean wear time:12.3 ± 3.2 days). The overall arrhythmia detection rate was higher with 14-day ECG patches (59.5%) compared to 24-h Holter (19.0%, P < 0.001). Up to 87.2% of arrhythmias recorded with 14-day ECG patches were not associated with symptoms. The 14-day ECG patch was associated with higher detection rates compared to the 24-h Holter in patients with SVT (52.5% versus 15.8%, P < 0.001), irregular SVT without P wave (12.7% versus 4.4%, P = 0.002), AF/AFL (9.5% versus 3.8%, P = 0.042), and critical arrhythmias (pause ≥3 s, AVB, VT, polymorphic VT) (16.5% versus 2.5%, P < 0.001). The 14-day ECG patch detected more than 2 types of arrhythmias in 5.1% of patients. No serious adverse events in patients wearing the 14-day ECG patch were reported.

CONCLUSIONS

The 14-day ECG patch outperformed 24-h Holter to detect overall, asymptomatic, critical and multiple arrhythmias. It is safe and has the potential to identify individuals with hidden arrhythmias, especially those with critical arrhythmias.

A simplified differential pacing technique for the evaluation of bidirectional cavo-tricuspid isthmus block during ablation of typical atrial flutter

PURPOSE

Bidirectional block of the cavo-tricuspid isthmus (CTI) is an established endpoint of CTI-dependent atrial flutter (AFl) ablation. Differential pacing has been used to evaluate the CTI block. The purpose of this study is to describe a modified differential pacing technique to evaluate the CTI block.

METHODS

Sixty-two patients underwent radiofrequency (RF) ablation of CTI-dependent AFl. The acute endpoints were non-inducibility of the AFl, and verification of the bidirectional CTI block by our methodology. Pacing was performed in the CS with an ablation catheter positioned immediately lateral to the CTI ablation line, and then 1-2 cm more laterally. The stimulus-to-ablation catheter atrial electrogram intervals were measured at these sites (Stim_CS-Abl₁ and Stim_CS-Abl₂, respectively). Pacing with the ablation catheter also was performed at these 2 sites, and the stimulus-to-CS electrogram intervals (Stim_ABL1-CS and Stim_ABL2-CS) were measured. The criteria for the bidirectional block were Stim_CS-Abl₁ > Stim_CS-Abl₂, and Stim_ABL1-CS > Stim_ABL2-CS. Clinical efficacy was defined as freedom from recurrent AFl during follow-up.

RESULTS

Following 12.2 ± 3.7 min of RF delivery across the CTI, intervals were Stim_CS-Abl₁ = 181.2 ± 22.7 ms and Stim_ABL1-CS = 181.0 ± 23.6 ms, and Stim_CS-Abl₂ = 152.2 ± 26.5 ms and Stim_ABL2-CS = 151.2 ± 22.7 (P < 0.001). Atrial flutter was rendered not inducible in all patients, and no procedural complications were encountered. During the next 15.9 ± 0.7 months, two patients were lost to follow-up, and among the 62 other patients, one (1.7%) had flutter recurrence.

CONCLUSIONS

The bidirectional CTI block can be assessed quickly and easily using only the ablation and CS catheters for differential pacing.

Assessment of the hemogram parameters in patients with paroxysmal supraventricular tachycardia: a retrospective study

OBJECTIVE

Inflammation has been suggested as a potential mechanism in the pathogenesis of arrhythmia. Hemogram parameters such as monocyte count to high-density lipoprotein cholesterol ratio (MHR), neutrophil/lymphocyte ratio (NLR), and monocyte/lymphocyte ratio (MLR) have been considered to be markers of inflammation and new cardiovascular risk predictors. This retrospective study aimed to investigate the relationship between MHR, NLR, and MLR in patients with paroxysmal supraventricular tachycardia (PSVT).

METHODS

A retrospective study conducted at a university hospital in Bolu, Turkey, between 2017 and 2019. Our study included 196 patients who underwent electrophysiological study (EPS) due to palpitation or documented PSVT on electrocardiography (ECG). Patients having documented atrioventricular nodal re-entrant tachycardia (AVNRT) on ECG or inducible AVNRT on EPS were included in the PSVT group (n=130), and patients with palpitation but without inducible arrhythmia on EPS (n=66) were included in the control group. Routine biochemical and hemogram tests were performed before the EPS procedure.

RESULTS

When hemogram parameters were compared, there was no statistically significant difference in MHR values [0.010 (0.001-0.030) vs 0.010 (0.001-0.020) p =0.67]. Additionally, both NLR [2.21(0.74-11.36) vs 1.98(0.72-24.87) p=0.13] and MLR [0.25 (0.03-1.05) vs 0.24(0.07-1.39) p=0.41] were not statistically significant between the two groups.

CONCLUSION

There is no significant difference in PSVT patients regarding hemogram parameters including white blood cell subtypes, MLR, NLR, and MHR. Therefore the evaluation of hemogram parameters may not be clinically relevant for PSVT patients.

Review paper on WPW and athletes: Let sleeping dogs lie?

Accessory pathways are present in 1 in 300 young individuals. They are often asymptomatic and potentially lethal arrhythmias may be the first presentation. During long-term follow-up, up to 20% of asymptomatic individuals with pre-excitation go on to develop an arrhythmia and the absence of traditional clinical and electrophysiological high-risk markers does not guarantee the "safe" nature of an accessory pathway. The widespread availability of permanent cure for the condition at low risk by catheter ablation, creates an incentive to screen for accessory pathways with a 12-lead ECG, particularly in individuals who are perceived to be at increased risk, such as athletes and high-risk professions. We review the existing literature on the assessment and management of accessory pathways (Wolff-Parkinson-White [WPW] syndrome) and discuss its implications for the young athletic population.

Thyroid dysfunction in patients with suspected or documented supraventricular tachyarrhythmia

Background and objectives

The association between thyroid dysfunction and supraventricular tachyarrhythmia (SVT) other than atrial fibrillation (AF) is not well elucidated. We hypothesized that patients with suspected or documented SVT have undetected thyroid dysfunction more frequently than general population.

Subjects and methods

Patients with symptoms suggestive of SVT other than AF who were planned to undergo an EP study at our center were eligible for this study. Patients with known thyroid disease, medications affecting thyroid function test (TFT) or atrial fibrillation were excluded. The primary outcome was prevalence of TFT abnormalities in the study population. The secondary outcome was prevalence of clinically significant arrhythmia during the EP study.

Results

A total of 533 patients were analyzed. Patients were divided into the two groups according to TFT results. Fifty-six (10.5%) patients had abnormal TFT results (thyroid dysfunction group), while 477 (89.5%) had normal thyroid function (euthyroidism group). The overall prevalence of thyroid dysfunction was 10.5%. The thyroid dysfunction group showed a tendency for higher induction of clinically significant SVT than the euthyroidism group. However, thyroid dysfunction was not an independent predictor of clinically significant SVT during EP study.

Conclusion

In this study, patients with suspected SVT who were planned for EP study had a relatively high incidence of thyroid dysfunction. Clinically significant arrhythmia tended to be induced more frequently in the thyroid dysfunction group than in the euthyroidism group. Further investigations are needed to verify the clinical implications of TFT in patients with SVT other than AF.

Arrhythmia Mechanisms and Outcomes of Ablation in Pediatric Patients With Congenital Heart Disease

BACKGROUND

In contrast to the adult population with congenital heart disease (CHD), arrhythmia mechanisms and outcomes of ablation in pediatric patients with CHD in recent era have not been studied in detail. Aims of this study were to determine arrhythmia mechanisms and to evaluate procedural and long-term outcomes in pediatric patients with CHD undergoing catheter ablation.

METHODS

Consecutive patients <18 years of age with CHD undergoing catheter ablation over an 11-year period (2007-2018) were included. Procedural outcome included complete or partial success, failure or empirical ablation. Long-term outcome included arrhythmia recurrence and burden according to a 12-point clinical arrhythmia severity score.

RESULTS

The study population consisted of 232 patients (11.7 years [0.01-17.8], 33.5 kg [2.2-130.1]). The most common diagnoses were Ebstein's anomaly (n=44), septal defects (n=39), and single ventricle (n=36). Arrhythmia mechanisms included atrioventricular reentry tachycardia (n=104, 90 patients), atrioventricular nodal reentry tachycardia (n=33, 29 patients), twin atrioventricular nodal tachycardia (n=3, 2 patients), macroreentrant atrial tachycardia (n=59, 56 patients), focal atrial tachycardia (n=33, 25 patients), ventricular ectopy (n=10, 8 patients), and ventricular tachycardia (n=15, 13 patients). Fifty-six arrhythmias (39 patients) were undefined. Outcomes included complete success (n=189, 81%), partial success (n=7, 3%), failure (n=16, 7%), or empirical ablation (n=20, 9%). Over 3.6 years (0.3-10.7) arrhythmia recurred in 49%. Independent of arrhythmia recurrence, arrhythmia scores decreased from 4 (0-10) at baseline to 0.5 (0-8) at 4 years follow-up (P<0.001). In 23/51 repeat procedures (45%), a different arrhythmia substrate was found. Overall adverse event rate was 9.4%, although only 1.6% (n=4) were of major severity and 0.8% (n=2) of moderate severity.

CONCLUSIONS

Pediatric patients with CHD demonstrate a broad spectrum of arrhythmia mechanisms. Despite recurrence and emergence of novel mechanisms after a successful procedure, ablation can be performed safely and successfully resulting in decreased arrhythmia burden.

Detecting Atrial Fibrillation and Atrial Flutter in Daily Life Using Photoplethysmography Data

OBJECTIVE

Photoplethysmography (PPG) enables unobtrusive heart rate monitoring, which can be used in wrist-worn applications. Its potential for detecting atrial fibrillation (AF) has been recently presented. Besides AF, another cardiac arrhythmia increasing stroke risk and requiring treatment is atrial flutter (AFL). Currently, the knowledge about AFL detection with PPG is limited. The objective of our study was to develop a model that classifies AF, AFL, and sinus rhythm with or without premature beats from PPG and acceleration data measured at the wrist in daily life.

METHODS

A dataset of 40 patients was collected by measuring PPG and accelerometer data, as well as electrocardiogram as a reference, during 24-hour monitoring. The dataset was split into 75%-25% for training and testing a Random Forest (RF) model, which combines features from PPG, inter-pulse intervals (IPI), and accelerometer data, to classify AF, AFL, and other rhythms. The performance was compared to an AF detection algorithm combining traditional IPI features for determining the robustness of the accuracy in presence of AFL.

RESULTS

The RF model classified AF/AFL/other with sensitivity and specificity of 97.6/84.5/98.1% and 98.2/99.7/92.8%, respectively. The results with the IPI-based AF classifier showed that the majority of false detections were caused by AFL.

CONCLUSION

The PPG signal contains information to classify AFL in the presence of AF, sinus rhythm, or sinus rhythm with premature contractions.

SIGNIFICANCE

PPG could indicate presence of AFL, not only AF.

An artificial intelligence-enabled ECG algorithm for the identification of patients with atrial fibrillation during sinus rhythm: a retrospective analysis of outcome prediction

BACKGROUND

Atrial fibrillation is frequently asymptomatic and thus underdetected but is associated with stroke, heart failure, and death. Existing screening methods require prolonged monitoring and are limited by cost and low yield. We aimed to develop a rapid, inexpensive, point-of-care means of identifying patients with atrial fibrillation using machine learning.

METHODS

We developed an artificial intelligence (AI)-enabled electrocardiograph (ECG) using a convolutional neural network to detect the electrocardiographic signature of atrial fibrillation present during normal sinus rhythm using standard 10-second, 12-lead ECGs. We included all patients aged 18 years or older with at least one digital, normal sinus rhythm, standard 10-second, 12-lead ECG acquired in the supine position at the Mayo Clinic ECG laboratory between Dec 31, 1993, and July 21, 2017, with rhythm labels validated by trained personnel under cardiologist supervision. We classified patients with at least one ECG with a rhythm of atrial fibrillation or atrial flutter as positive for atrial fibrillation. We allocated ECGs to the training, internal validation, and testing datasets in a 7:1:2 ratio. We calculated the area under the curve (AUC) of the receiver operatoring characteristic curve for the internal validation dataset to select a probability threshold, which we applied to the testing dataset. We evaluated model performance on the testing dataset by calculating the AUC and the accuracy, sensitivity, specificity, and F1 score with two-sided 95% CIs.

FINDINGS

We included 180 922 patients with 649 931 normal sinus rhythm ECGs for analysis: 454 789 ECGs recorded from 126 526 patients in the training dataset, 64 340 ECGs from 18 116 patients in the internal validation dataset, and 130 802 ECGs from 36 280 patients in the testing dataset. 3051 (8·4%) patients in the testing dataset had verified atrial fibrillation before the normal sinus rhythm ECG tested by the model. A single AI-enabled ECG identified atrial fibrillation with an AUC of 0·87 (95% CI 0·86-0·88), sensitivity of 79·0% (77·5-80·4), specificity of 79·5% (79·0-79·9), F1 score of 39·2% (38·1-40·3), and overall accuracy of 79·4% (79·0-79·9). Including all ECGs acquired during the first month of each patient's window of interest (ie, the study start date or 31 days before the first recorded atrial fibrillation ECG) increased the AUC to 0·90 (0·90-0·91), sensitivity to 82·3% (80·9-83·6), specificity to 83·4% (83·0-83·8), F1 score to 45·4% (44·2-46·5), and overall accuracy to 83·3% (83·0-83·7).

INTERPRETATION

An AI-enabled ECG acquired during normal sinus rhythm permits identification at point of care of individuals with atrial fibrillation.

FUNDING

None.

The Electrocardiogram: Still a Useful Tool in the Primary Care Office

A 12-lead electrocardiogram (ECG) is the most commonly ordered cardiac test. Although data are not robust, guidelines recommend against performing an ECG in patients who are asymptomatic, even if they have a higher risk of developing cardiovascular disease in the long term. Conversely, patients with cardiac symptoms, including chest pain, dyspnea, palpitation, and syncope, should have an ECG performed in the office. Computerized algorithms exist ubiquitously to guide interpretation, but they can be the source of erroneous information. A stepwise approach is given to guide the primary care physician's approach to the systematic interpretation of ECG tracings.

Early repolarization in the inferior leads after accessory pathway ablation is highly correlated with atrial fibrillation in Wolff-Parkinson-White syndrome

BACKGROUND

Both atrial fibrillation (AF) and early repolarization (ER) are highly prevalent in patients with Wolff-Parkinson-White (WPW) syndrome.

METHODS

We retrospectively identified 123 WPW patients with manifest accessory pathway (mAP) and 105 patients with concealed accessory pathways (cAP) who underwent successful ablation of the APs. AF history prior to the ablation was investigated. The presence of ER was evaluated from the 12-lead electrocardiograms performed both before and immediately after the ablation. Patients were further followed up for AF occurrence after the AP ablation.

RESULTS

Compared with cAP patients, WPW patients presented with higher incidence of previous AF, as well as ER after the AP ablation. Compared with those without AF history, WPW patients with comorbid AF were more prone to presenting ER, especially in the inferior leads, after the mAP ablation. Regression analysis suggested that the post-ablation ER in the inferior leads was strongly associated with AF in WPW patients [OR = 5.85; 95% confidence interval (CI): 2.29-14.96], even after adjusting for age and left atrial diameter (OR = 5.14; 95% CI: 1.80-14.74). Moreover, post-ablation inferior-lead ER was predictive of AF recurrence after mAP ablation during the follow-up of 22.6 ± 11.1 months. In comparison, ER was correlated with neither AF history nor AF recurrence in patients undergoing cAP ablation.

CONCLUSIONS

ER in the inferior leads after the mAP ablation is highly correlated with AF history and recurrence in WPW patients.

High prevalence of hyperlipidaemia in patients with AV re-entry tachycardia and AV nodal re-entry tachycardia

Diet rich in lipids and hyperlipidaemia increases incidence of atrial premature beats and all supraventricular arrhythmias. The aim of the study was to investigate the prevalence of hyperlipidaemia in patients with AV re-entry tachycardia (AVRT) and AV nodal re-entry tachycardia (AVNRT). We conducted a retrospective, cross-sectional, case-control study that included all consecutive patients for whom AVRT or AVNRT was confirmed during electrophysiology study. Age and gender-matched patients admitted to hospital or outpatient clinic for various reasons were randomly included and served as a control group. Hyperlipidaemia was defined according to 2016 European Society of Cardiology guidelines. A total of 1448 subjects were included: 725 patients with AVRT/AVNRT and 723 controls. AVRT/AVNRT patients had high hyperlipidaemia prevalence, which was significantly higher when compared to the control group (50.1 vs. 35.8%, p < 0.001). AVRT patients, with median age of 37.5 years, had hyperlipidaemia prevalence of 45.7%. In a multivariate analysis, hyperlipidaemia was independently associated with AVRT/AVNRT (OR 2.128, p < 0.001), both with AVNRT (OR 1.878, p < 0.001) and AVRT (OR 2.786, p < 0.001). Hypercholesterolemia was significantly more prevalent in patients with AVNRT and AVRT, while this was not the case for hypertriglyceridemia. There were no differences between the AVRT and AVNRT patients regarding hyperlipidaemia prevalence (51.9 vs. 45.7%, p = 0.801), even though AVRT patients were significantly younger (37.5 vs. 48.5, p < 0.001). In conclusion, this is the first study that investigated hyperlipidaemia prevalence in patients with AVRT or AVNRT. AVRT/AVNRT patients had higher prevalence of hyperlipidaemia and higher total and LDL cholesterol levels.

Intracardiac echocardiography versus fluoroscopy for endovascular and endocardial catheter navigation during cryo-ablation of the slow pathway in AVNRT patients

Background

A new zero-fluoroscopy technique for electrophysiology catheter navigation relying on intracardiac echocardiography (ICE) has been recently reported (Ice&ICE trial). We investigated potential differences in efficacy, safety or procedural performance between conventional fluoroscopy- and ICE-guided cryothermal ablation (CA) in symptomatic AVNRT patients.

Methods

Clinical and electrophysiological data of AVNRT patients included in the Ice&ICE trial (22 patients, 16 females; =zero-fluoroscopy group) were compared to those of consecutive AVNRT patients, who underwent fluoroscopy-guided CA (25 patients, 17 females; = fluoroscopy group) during the last 2 years in our institution.

Results

Slow pathway ablation or modulation was successful in all patients. Fluoroscopy time and radiation dose in the fluoroscopy group were 11.2 ± 9.0 min and 20.3 ± 16.2Gycm², whereas no fluoroscopy was used in the opposite group (p <  0.001, respectively). EPS duration was not different between the groups (zero-fluoroscopy:101.6 ± 40.2 min, fluoroscopy:99.4 ± 37.2 min, p = n.s.). Catheter placement time was significantly shorter in the fluoroscopy group (2.2 ± 1.6 min vs. 12.0 ± 7.5 min, p <  0.05), whereas cryo-application duration (from the first cryo-mapping to the last CA) was significantly shorter in the zero-fluoroscopy group (27.5 ± 37.0 min vs. 38.1 ± 33.9 min, p <  0.05). Mean cryo-mapping and CA applications were numerically lower in the zero-fluoroscopy group (CM:7.5 ± 5.7 vs. 8.8 ± 6.2; CA:3.1 ± 1.7 vs. 3.2 ± 2.0, p = n.s.). No major adverse events occurred in both groups. After 15.0 ± 4.2 months, arrhythmia recurrence was not different between the groups (4.5% vs. 8.0%, p = n.s.).

Conclusions

Zero-fluoroscopy ICE-guided EP catheter navigation shows comparable efficacy and safety to fluoroscopic guidance during CA in AVNRT patients. ICE visualization of catheters and endocardial structures within the triangle of Koch shortens the cryo-application duration, though time needed for catheter placement is longer, when compared with conventional fluoroscopic guidance, which results in similar mean EPS duration with both navigation techniques.

Trial registration

(German Clinical Trials Register ID: DRKS00011360; Registration Date 14.12.2016)

Electronic supplementary material

The online version of this article (10.1186/s12947-019-0162-2) contains supplementary material, which is available to authorized users.

Indications for β-Blocker Prescriptions in Heart Failure with Preserved Ejection Fraction

OBJECTIVES

To better understand indications for β-blocker (BB) prescriptions among older adults hospitalized with heart failure with preserved ejection fraction (HFpEF).

DESIGN/SETTING

Retrospective observational study of hospitalizations derived from the geographically diverse Reasons for Geographic and Racial Differences in Stroke cohort.

PARTICIPANTS

We examined Medicare beneficiaries aged 65 years or older with an expert-adjudicated hospitalization for HFpEF (left ventricular ejection fraction = 50% or greater).

MEASUREMENTS

Discharge medications and indications for BBs were abstracted from medical records.

RESULTS

Of 306 hospitalizations for HFpEF, BBs were prescribed at discharge in 68%. Among hospitalizations resulting in BB prescriptions, 60% had a compelling indication for BB-44% had arrhythmias, and 29% had myocardial infarction (MI) history. Among the 40% with neither indication, 57% had coronary artery disease (CAD) without MI and 38% had hypertension alone (without arrhythmia, MI, or CAD), both clinical scenarios with little supportive evidence of benefit of BBs. Among hospitalizations resulting in BB prescription at discharge, 69% had geriatric conditions (functional limitation, cognitive impairment, hypoalbuminemia, or history of falls). There were no significant differences in the prevalence of geriatric conditions between hospitalizations of individuals with compelling indications for BBs and hospitalizations of individuals with noncompelling indications.

CONCLUSIONS

BBs are commonly prescribed following a hospitalization for HFpEF, even in the absence of compelling indications. This occurs even for hospitalizations of individuals with geriatric conditions, a subpopulation who may be at elevated risk for experiencing harm from BBs.

Prevalence and clinical characteristics of Danon disease among patients with left ventricular hypertrophy and concomitant electrocardiographic preexcitation

BACKGROUND

Cardiac involvement in Danon disease typically manifests as left ventricular hypertrophy (LVH) and ventricular preexcitation. This study aimed to identify patients with Danon disease among patients with LVH and concurrent electrocardiographic preexcitation.

METHODS

Electrocardiographic preexcitation was identified in 10 of 197 patients with unexplained LVH in whom genetic testing was performed using next-generation sequencing.

RESULTS

Three (3/10, 30%) patients with Danon disease were found in association with different mutations in the gene of lysosome-associated membrane protein 2 (LAMP2). Compared to seven patients without Danon disease, these three patients presented with distinctive clinical phenotypes, including onset at an earlier age (20 ± 2 years vs. 53 ± 9 years, p < 0.001), more neurological involvements (100% vs. 0, p = 0.008), higher electrocardiographic voltages (10 ± 1 mV vs. 5 ± 1 mV, p < 0.001), wider QRS complexes (163 ± 5 ms vs. 115 ± 20 ms, p = 0.006), less common asymmetric hypertrophy (0% vs. 86%, p = 0.033), and more frequent elevation of three serum enzymes (creatine kinase, aspartate aminotransferase, and lactate dehydrogenase). Intracellular vacuoles accumulation with deficiencies of LAMP2 protein was found in both cardiac and skeletal myocytes of patients with Danon disease.

CONCLUSION

In patients with coexistent LVH and ventricular preexcitation, Danon disease is common with distinctive clinical presentations. Comprehensive assessment of these resemble patients can provide valuable findings for early identification and clinical decision making of patients with Danon disease.