Treatment Of Supraventricular Tachycardia Research Articles

Prolonged sinus pauses after the paroxysms of atrial tachycardia in children, to pace or to ablate? Case report

Background. The presence of prolonged sinus pauses is quite rare in children and adolescents with structural normal heart. The decision of the optimal therapeutic tactics is always challenging. Case report. The 16-years-old girl addressed with complains of palpitations and dizziness after the palpitations end. A Holter ECG monitoring was performed with the detection of prolonged sinus pauses after the paroxysm of atrial tachycardia. We decided to perform an electrophysiological study to diagnose the tachycardia type. The presence of atrial tachycardia originating from the ostium of the coronary sinus was demonstrated. We decided to manage the tachyarrhythmia with catheter ablation. During the application of the radiofrequency currents, the tachycardia stopped, and the sinus rhythm was restored. The ablation was preferred over medication taking into consideration the potential risk of worsening of the bradycardia by antiarrhythmic therapy. Conclusions. The optimal therapeutic solution in similar pediatric cases should be directed towards the supraventricular tachycardia treatment and not to the bradyarrhythmia. The majority of supraventricular tachycardias could be cured by catheter ablation.

Effectiveness of modified Valsalva maneuver by using wide bore syringe for emergency treatment of supraventricular tachycardias: Findings from Pakistan.

The Valsalva maneuver (VM) is the most effective measure that can be carried out to treat supraventricular tachycardia (SVT). Our objective was to compare the efficacy of postural modified VM with 20 ml syringe to standard VM for the emergency treatment of SVT. This randomized control trial study was conducted at the Accident and Emergency Department, Pakistan ordinance factories hospital, Wah Cantt from July 2019 to September 2020. In the standard Valsalva group, fifty patients were placed at an angle of 45 with continuous monitoring of vitals and electrocardiogram. Patients blew into a 20ml syringe to generate 40 mmHg pressure for 15 seconds and remained in the same position for 45 seconds before a reassessment of cardiac rhythm at one-minute and three-minute intervals. In the modified Valsalva group same procedure was repeated with the other fifty patients, but immediately at the end of the strain, they were laid flat with their legs raised to 45° for 15 seconds. Participants returned to semi-recumbent position and cardiac rhythm was reassessed after 45 seconds and then at one and three minutes. In the standard Valsalva maneuver (SVM)20.0% of participants versus 58% of participants in the modified Valsalva maneuvers group(MVM) reverted to sinus rhythm at one min (odds ratio or 5.52, 95% CI 2.26-13.47; p<0.001) and time of stay in the emergency room was (odds ratio or 2.39, 95% CI 1.45- 3.93; p<0.0001). Modified Valsalva by using a wide-bore syringe is more effective method than standard Valsalva in terminating SVT.

Assessing the Risk of Hypoglycemia Secondary to Propranolol Therapy for the Treatment of Supraventricular Tachycardia in Infants

Supraventricular tachycardia (SVT) is the most common arrhythmia among infants. Prevention of SVT is frequently managed through propranolol therapy. Hypoglycemia is a known adverse effect of propranolol therapy, but little research has been done on the incidence and risk of hypoglycemia in treatment of SVT in infants with propranolol. This study attempts to offer insight into the risk of hypoglycemia associated with propranolol therapy when treating infantile SVT to help inform future glucose screening guidelines. We conducted a retrospective chart review of infants treated with propranolol in our hospital system. Inclusion criteria were infants < 1year of age who received propranolol for the treatment of SVT. A total of 63 patients were identified. Data was collected on sex, age, race, diagnosis, gestational age, nutrition source (Total Parenteral Nutrition (TPN) vs oral), weight (kg), weight for length (kg/cm), propranolol dose (mg/kg/day), comorbidities, and whether or not a hypoglycemic event was identified (< 60mg/dL). Hypoglycemic events were identified in 9/63 (14.3%) patients. Of the patients with hypoglycemic events, 9/9 (88.9%) had comorbid conditions. Patients with hypoglycemic events had significantly lower weight and propranolol dose than those without hypoglycemic events. Weight for length also tended to increase risk for hypoglycemic events. The high incidence of comorbid conditions in the patients who had hypoglycemic events suggests that hypoglycemic monitoring may only be necessary in patients with conditions predisposing to hypoglycemia.

Safety of Adenosine for the Treatment of Supraventricular Tachycardia in Hospitalized Patients with COVID-19 Pneumonia.

Coronavirus disease 2019 (COVID-19) is associated with pulmonary involvement and cardiac arrhythmias, including supraventricular tachycardia (SVT). Adenosine is commonly used to treat SVT and is generally safe, but is rarely associated with bronchospasm. There are no data regarding the safety of adenosine use in patients with COVID-19 pneumonia and physicians may hesitate to use it in such patients. We surveyed resident physicians and cardiology attendings regarding their level of comfort in administering adenosine to hospitalized COVID-19 patients. We compared a study group of 42 COVID-19 hospitalized patients who received adenosine for SVT to a matched (for age, sex, and co-morbidities) control group of 42 non-COVID-19 hospitalized patients during the same period, all of whom received IV adenosine for SVT. Escalation of care following intravenous adenosine administration was defined as increased/new pressor requirement, need for higher O2 flow rates, need for endotracheal intubation, new nebulizer therapy, or transfer to intensive care unit within 2 h of adenosine administration. Survey results showed that 82% (59/72) of residents and 62% (16/26) of cardiologists expressed hesitation/significant concerns regarding administering adenosine in hospitalized COVID-19 patients. Adenosine use was associated with escalation of care in 47.6% (20/42) COVID-19 as compared to 50% (21/42) non-COVID-19 patients (odds ratio 0.95, 95% CI 0.45-2.01, p = NS). Escalation of care was more likely in patients who were on higher FiO2, on prior nebulizer therapy, required supplemental oxygen, or were already on a ventilator. In conclusion, we identified significant hesitation among physicians regarding the use of adenosine for SVT in hospitalized COVID-19 patients. In this study, there was no evidence of increased harm from administering adenosine to patients with SVT and COVID-19. This finding needs to be confirmed in larger studies. Based on the current evidence, adenosine for treatment of SVT in this setting should not be avoided. Key Points: Question: Given the known bronchospastic effects of adenosine, is the use of adenosine safe for treatment of supraventricular tachycardia in hospitalized patients with COVID-19? Findings: A survey of residents and cardiology attending identified that a majority expressed some level of apprehension in using adenosine for SVT in COVID-19 patients. In our matched cohort study, we found adenosine use to be comparably safe in COVID-19 and non-COVID-19 hospitalized patients. Meaning: Based on current evidence, adenosine for treatment of SVT in this setting should not be avoided.

Algorithms for the prevention and treatment of supraventricular tachycardia in patients with implanted pacemakers: case series

Two clinical cases of prevention and relief of supraventricular tachycardia using modern algorithms in pacemakers of the latest generation in patients with bradyarrhythmia and paroxysmal atrial fibrillation (AF) are presented. In the first clinical case, the patient did not have an episode of AF for six months. In the second clinical case, the patient for 2 years did not have an episode of AF lasting more than 1 minute. Episodes sinus rhythm restoration by antitachypacing algorithms were recorded. These clinical cases demonstrate the effectiveness of modern algorithms in pacemakers of the latest generation for the AF prevention and sinus rhythm restoration.

Health Disparities in the Treatment of Supraventricular Tachycardia in Pediatric Patients.

Supraventricular tachycardia (SVT)is a common pediatric arrhythmia. The objective of this investigation was to investigate the existence and degree of the health disparities in the treatment of pediatric patients with supraventricular tachycardia based on sociodemographic factors. This was retrospective cohort study at a large academic medical center including children ages 5-18years old diagnosed with SVT. Patients with congenital heart disease and myocarditis were excluded. Initial treatment and ultimate treatment with either medical management or ablation were determined. The odds of having an ablation procedure were determined based on patient age, sex, race, ethnicity, and insurance status. There was a larger portion of non-White patients (p = 0.033) within the cohort that did not receive an ablation during the study period. Patients that were younger, female, American Indian/Alaskan Native, unknown race, and had missing insurance information were less likely to receive ablation therapy during the study period. In this single center, regional evaluation, we demonstrated that disparities in the treatment of pediatric SVT are present based on multiple patient sociodemographic factors. This study adds evidence to the presence of inequities in health care delivery across pediatric populations.

Atrial Fibrillation with Ventricular Pre-Excitation: A Diagnosis That Must Not Be Missed

Wolff-Parkinson-White (WPW) syndrome is caused by an accessory pathway that communicates between the atria and ventricles known as the Bundle of Kent. The development of atrial fibrillation, can result in the atrial impulses all being conducted via the accessory pathway and result in a sinister, board complex, irregular tachycardia, with varying QRS morphology (known as pre-excited atrial fibrillation) Adenosine is a potent atrioventricular node blocker, which can be used in the treatment of supraventricular tachycardias, but also has diagnostic utility, particularly in differentiating between supraventricular tachycardia with aberrant conduction (which would often terminate) and a ventricular tachycardia (which would not respond to adenosine). However, the administration of adenosine in pre-excited atrial fibrillation can precipitate 1:1 atrial to ventricular conduction, which can degenerate into life-threatening ventricular arrythmias. This case describes a patient who presented with pre-excited atrial fibrillation and received intravenous adenosine that resulted in development of broad complex tachycardia with haemodynamic compromise. In patients with pre-exited atrial fibrillation, AV nodal blocking agents should be avoided and direct current cardioversion should be utilised.

Neonatal Supraventricular Tachycardia: Outcomes Over a 10-Year Period at a Single Institution

Objective: Supraventricular tachycardia, one of the most common conditions requiring emergency cardiac intervention in newborns, is also the most common symptomatic tachyarrhythmia in newborns. Therefore, early diagnosis and treatment approach is important. &#x0D; Method: Demographic findings, clinical findings, and treatment approaches of newborns hospitalized with the diagnosis of supraventricular tachycardia between January 2011 and November 2020 in the Neonatal Intensive Care Unit of our hospital were evaluated retrospectively. &#x0D; Results: Thirty-eight patients without congenital heart disease (except secundum-type atrial septal defect) and diagnosed with supraventricular tachycardia were evaluated retrospectively. The mean week of gestation was 38.2 ± 1.8, the mean age at diagnosis was 10.7 ± 10.1 days, the number of patients with heart failure was 8 (21%), the number of patients with Wolff-Parkinson White syndrome was 8 (21%), the number of patients with fetal arrhythmia was 6 (15.7%) and the mean number of hospitalization days was 15.7±13.5. The patients were given adenosine in the first stage and propranolol, amiodarone, propafenone and flecainide in the second stage as medical treatment. Cardioversion was performed in 5 (13%) patients due to resistant supraventricular tachycardia. &#x0D; Conclusion: Early diagnosis and treatment of supraventricular tachycardia are very important in terms of reducing morbidity and mortality. Therefore, we think that increasing awareness of supraventricular tachycardia among clinicians following newborn babies will enable newborns with supraventricular tachycardia to receive early diagnosis and treatment.

Abstract 14388: Efficacy of Intravenous Procainamide for Treatment of Tachyarrhythmia in Children

Introduction: The safety and efficacy of IV procainamide is well established in adults, however data in pediatrics is more limited. Methods: Prospective cohort study including children &lt;18 yrs old who received IV procainamide for supraventricular tachycardia (SVT) or junctional ectopic tachycardia (JET) from June 2020 to May 2021. A severity of arrhythmia score (SAS, table), including arrhythmia density score (ADS), hemodynamic severity and need for adjunctive antiarrhythmic therapy was calculated pre and post procainamide. Full success was defined as decrease of the ADS to 0 and partial success as decrease by ≥50%. Results: Fifty-three patients (6.9 [IQR 1.2-34.9] months) received IV procainamide for treatment of SVT (n = 25, 47%) or JET (n = 28, 52%), including 44 (83%) with congenital heart disease (CHD) and 39 (74%) following cardiac surgery. Fifty (93%) patients were given a bolus (median 5 mg/kg, range 2.5-13 mg/kg) and 52 (96%) received an infusion (median 20 mcg/kg/min, range 10-30 mcg/kg/min). Full success was observed in 28 (53%) patients, partial success in 13 (25%) and failure in 12 (23%); 7 (19%) patients required adjunctive IV antiarrhythmic therapy. Median SAS decreased from 6 (IQR 4-8) to 1 (IQR 1-5) following procainamide. Procainamide bolus &gt;5 mg/kg was associated with greater decrease in SAS (median decrease 5 [4-6] vs 2 [0-4], p = 0.04). Children with CHD (median decrease 1 [IQR 0-4] vs 4 [IQR 4-5], p = 0.04), those in the early post-operative period (median decrease 2 [IQR 0-4] vs 4 [IQR 4-5], p = 0.03) and those with JET (median decrease 2 [IQR 0-4] vs 4 [IQR 2-5], p = 0.04) had less improvement in SAS score with procainamide. Conclusions: IV procainamide is effective for treatment of SVT and JET in children, and associated with decreased SAS even in patients without complete rhythm control. Higher procainamide bolus dose should be considered for increased efficacy. Future studies are needed to identify optimal doses in pediatrics.

Recurrent Symptomatic Supraventricular Tachycardia In A Collegiate Volleyball Player

ACSM Case Report SubmissionCalan Sowa, MD HISTORY: A 21-year-old collegiate women’s volleyball player with a past medical history of supraventricular tachycardia (SVT) ablated in July of 2020 presented to the training room after developing shortness of breath and palpitations while participating in volleyball practice. Her symptoms arose spontaneously, and she experienced no chest pain or dizziness, endorsed no recent fevers or chills and had no recent sick contacts. She had no history of illicit substance use and had been otherwise feeling well. PHYSICAL EXAMINATION: Examination in the training room revealed regular tachycardia at a rate of approximately 200 beats per minute. Blood pressure was within normal limits. The patient exhibited no dyspnea and bilateral lungs were clear to auscultation. Neurologic exam was within normal limits. EKG was not available in the training room and therefore the patient was instructed to report to the Emergency Room for further evaluation. DIFFERENTIAL DIAGNOSIS: 1. Supraventricular tachycardia2. Ventricular tachycardia3. Viral myocarditis TESTS AND RESULTS: Troponin I: normalBasic Metabolic Panel: normalEKG: Normal sinus rhythm with HR 56 bpm48-Hour Holter Monitor: -Predominant rhythm: SVT with normal AV conduction-Average HR: 75 bpm, Minimum HR 44 bpm, Maximum HR 194 bpm-Ectopy: Occasional PACs without ventricular ectopy-Dysrhythmias: Supraventricular tachycardia (SVT); 399 beats at 215 bpm-Symptoms: Palpitations and shortness of breath reported once at which time the rhythm was sinus with a rate of 53 bpm FINAL WORKING DIAGNOSIS: Recurrent SVT TREATMENT AND OUTCOMES: 48-hour Holter monitoring confirmed an episode of recurrent SVT lasting for approximately twenty seconds that occurred during participation in volleyball practice. The patient was referred to cardiology and ultimately elected to follow up with her home cardiologist in Virginia. She is awaiting evaluation and resulting medical/procedural management and return-to-play instruction.

World Congress of Perinatal Medicine

SPEAKERS ABSTRACTS The application of super slow review of ultrasound clips to a diagnosis of fetal tachyarrhythmia Name and surname: Jun Yoshimatsu Institution: National Cerebral and Cardiovascular Center Email: yoshimatsu.jun.hp@ncvc.go.jp Objective Fetal arrhythmias occur in 1–2% of all pregnant cases. Premature atrial contraction (PAC), premature ventricular contraction (PVC) which are clinically benign are relatively common and do not require therapy. In contrast supraventricular tachycardias (SVTs), atrial flutter (AFL), ventricular tachycardia which are life-threatening are relatively rare but require treatment. These tachyarrhythmias easily complicate fetal congestive heart failure which can be followed by a fetal death. Thus, prenatal treatment for SVT and AFL is warranted to convert to sinus rhythm. Recently our group demonstrated that protocol-defined transplacental treatment for fetal SVT and AFL was effective and tolerable in 90% of cases. In order to choose the appropriate medication for fetal tachyarrhythmia the accurate diagnosis is important. Because fetal electrocardiography is still not available fetal echocardiography is commonly used for the diagnosis of fetal arrhythmia. The M-mode and Doppler echocardiography may achieve prenatal identification of arrhythmic types. The easier method helps more accurate and precise diagnosis of it. Recent advances of ultrasound examination technology allows a high spatial resolution and high temporal resolution at the same time. The image editing of video clips of four chamber view, which is the most easier image plane, is applicable for the diagnosis of fetal arrhythmias. We conducted the research to innovate the useful video clip editing method including a super slow motion for the precise diagnosis of fetal arrhythmias. Method From our fetal echocardiography database, 55 fetal echocardiography video clips (35 AFL, 20 SVT) were reviewed. Four chamber view clips of each case were selected. Every clips were edited into 10% speed. One examiner inserted the clip maker at the timing of atrial contraction and ventricular contraction. The intervals between ventricular contraction and atrial contraction were measured. Also the number of times of contraction of atrium and ventricle and their relations were recorded. Results Every contractions of each portion (atrium and ventricle) could be detected easily with edited video clips. The differentiation between AFL and SVT could be done completely by counting the number of contractions of atrium and ventricle. Also the V-A intervals and the A-V intervals could be measured in one hundredth seconds. In all cases, the diagnosis is compatible with that had made postnatally. Conclusion The first step of this study was depended on the examiner’s naked eyes helped by editing application. The accuracy of each steps of this study were satisfactory. This is the preliminary step to conduct the deep learning of Artificial Intelligence (AI). The most important point of using AI is setting up what to teach and how to teach. Our study showed the possibility of the application of AI to make a diagnosis of fetal tachyarrhythmia.

Acute outcomes of three-dimensional mapping for fluoroscopy reduction in paediatric catheter ablation for supraventricular tachycardia.

Catheter ablation is a safe and effective therapy for the treatment of supraventricular tachycardia in children. Current improvements in technology have allowed progressive reduction in radiation exposure associated with the procedure. To assess the impact of three-dimensional mapping, we compared acute procedural results collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to published results from the Prospective Assessment after Pediatric Cardiac Ablation study. Inclusion and exclusion criteria from the Prospective Assessment after Pediatric Cardiac Ablation study were used as guidelines to select patient data from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to compare acute procedural outcomes between cohorts. Outcomes assessed include procedural and fluoroscopy exposure times, success rates of procedure, and complications. In 786 ablation procedures, targeting 498 accessory pathways and 288 atrioventricular nodal reentrant tachycardia substrates, average procedural time (156.5 versus 206.7 minutes, p < 0.01), and fluoroscopy time (1.2 versus 38.3 minutes, p < 0.01) were significantly shorter in the study group. Success rates for the various substrates were similar except for manifest accessory pathways which had a significantly higher success rate in the study group (96.4% versus 93.0%, p < 0.01). Major complication rates were significantly lower in the study group (0.3% versus 1.6%, p < 0.01). In a large, multicentre study, three-dimensional systems show favourable improvements in clinical outcomes in children undergoing catheter ablation of supraventricular tachycardia compared to the traditional fluoroscopic approach. Further improvements are anticipated as technology advances.

Supraventricular Tachycardia

Supraventricular tachycardia (SVT) is a category of arrhythmias that originate at or above the atrioventricular node. These are typically narrow complex QRS arrhythmias, without discernible P waves, with a regular rhythm and rapid rate. SVT is relatively common, occurring in 2.25 cases per 1,000 persons. Therefore, understanding the pathophysiology and method of treatment of SVT is an important skill for the emergency medicine physician to master. Therapeutic interventions include vagal maneuvers or pharmacologic agents, such as adenosine or calcium channel blockers, for the stable patient and synchronized cardioversion for the unstable patient. Stable patients with minimal comorbidities whose sinus rhythm is converted back in the emergency department can be safely discharged with a close follow-up by a cardiologist. However, admission is often required for the patient who presents with unstable SVT or has multiple comorbidities and requires further work-up. This review contains 10 figures, 3 tables, and 48 references. Keywords: ablation, adenosine, cardioversion, supraventricular tachycardia, valsalva maneuver, Wolff-Parkinson-White syndrome

Modern treatment of supraventricular tachycardia

Supraventricular tachycardia (SVT) is one of the most common arrhythmias. The prevalence of SVT varies widely in different countries and is 2,25 per 1,000 people in the general population. SVT reduce the quality of life of patients, and in some cases can worsen the prognosis. In patients with cardiovascular disease, the risk of SVT increases. Therapy of SVT is selected depending on the stability of hemodynamic and the QRS width. Until now, the treatment of SVT remains an urgent issue of modern cardiology, since despite the high effectiveness of catheter ablation, antiarrhythmic therapy plays an important role.

Supraventricular tachycardia: current methods of diagnosis and treatment (the focus on updated 2019 European Society of Cardiology clinical practice guidelines for the management of patients with supraventricular tachycardia)

The lecture is devoted to one of the most urgent problems in cardiology – management of patients with paroxysmal supraventricular tachycardia (SVT) in clinical practice. The main principles of the diagnosis of SVT and their electrophysiological mechanisms are outlined. Clinical presentation and ECG diagnosis of different forms of tachycardia are stated. The acute care and long-term treatment of SVT with narrow and wide QRS complex are presented. The methods of treatment and algorhythms of management of patients with SVT are given according to the updated ESC guidelines. The data on antiarrhythmic drugs and their usage are presented, along with the general principles of catheter treatment of tachycardia

Real world data on non-complex catheter ablations performed on zero fluoroscopy in a secondary centre in the south of Belgium

Objective We have designed a study, whose aim was to confirm the feasibility and safety of the zero fluoroscopy approach in the treatment of supraventricular tachycardias (SVT) and premature ventricular contractions (PVCs) originating in the right ventricle in a secondary centre located in the south of Belgium. Methods We included in our retrospective analysis patients with a clinical history and/or electrocardiographic documentation of SVT or frequent symptomatic monomorphic PVCs referred to our centre from November 2019 to March 2020 for catheter ablation. Results A total of 49 patients were considered eligible for potential enrolment in the study, 3 were excluded because of presence of a manifest left sided atrio-ventricular accessory pathway, 5 because of left ventricular PVCs and 4 because of left atrial tachycardia. 4 patients were instead excluded because of need of utilisation of fluoroscopy during the procedure. A total of 33 patients were therefore included in the analysis. Right atrial flutters and typical AVNRT were the most common arrhythmia treated, corresponding together to the 81% of the total. Right femoral access was obtained in 86% of cases with left femoral access used in the remaining when right femoral access was not successful after the third attempt. Coronary sinus cannulation was efficacious within 10 min in 76% of cases. There were four minor complications overall. Conclusion The main finding of our study is that non-complex ablations can be performed on zero-fluoroscopy safely and with a good clinical outcome also in a secondary centre.

Incidental Cardiac Arrhythmia Identification With Consumer Grade Heart Rate Monitors: A Case Study

HISTORY: A 19-year-old sophomore NCAA Division I female volleyball player was identified, via a consumer-grade heart rate (HR) telemetry system, as having what would be considered a high heart rate (123% of age predicted max HR or 233 bpm) during practice. PHYSICAL EXAMINATION: Athlete was observed without interaction for signs of distress, excessive heavy breathing, pallor changes, or any sort of balance issues that would indicate dizziness or syncope. After approximately 5 minutes, HR returned to a normal level that would be commensurate with the exercises/drills being performed. Once a more in-depth analysis of the collected data was performed it was determined that consultation with team physician and cardiologist was needed. Retrospective analysis of data recorded prior to this episode was undertaken and identified approximately 40% of recorded session contained a similar episode. Further clarification of both HR, and R-R interval data aided in identification of episodes. DIFFERENTIAL DIAGNOSIS: 1. Supraventricular tachycardia (SVT) 2. Wolf-Parkinson-White Syndrome 3. Atrioventricular Nodal Reentrant Tachycardia (AVNRT) TEST AND RESULTS: Electrocardiogram: --No noticeable abnormalities Holter Monitor: --identified an exercise induced SVT episode with no other abnormalities when episode was not present. --HR data was used to assist in identifying duration, initiation and termination of the episode. FINAL/WORKING DIAGNOSIS: Exercise induced SVT TREATMENT AND OUTCOMES: Athlete continued participation with continuous real time heart rate monitoring for episodic activity. When episodes of tachycardia occurred, the athlete was removed from practice/play until a return to normal HR was achieved. After conclusion of academic year an ablation was attempted to correct the problem. The remaining athletes using the HR telemetry system have performance data analyzed on a daily basis for possible identification of arrhythmic signatures. Currently development and implementation of a policy to address identified athletes is underway and will streamline addressing future instances.

233Conventional fluoroscopy guided vs zero-fluoroscopy catheter ablation of supraventricular tachycardias

Abstract Funding Acknowledgements None Introduction Conventionally, catheter movement and placement during catheter ablation (CA) is guided by X-ray fluoroscopy. In recent years, an ‘as low as reasonably possible’ principle was established to minimize the ionizing radiation dose received by the patient and the operator. Zero-fluoroscopy approach is at the extreme end of the spectrum of this principle. With exclusion of X-ray fluoroscopy, three-dimensional electroanatomical mapping system and intracardiac echocardiography are used for catheter guidance during ablation procedures. Purpose The aim of our study was to assess and compare procedural parameters and clinical outcomes of conventional X-ray fluoroscopy guided and zero-fluoroscopy CA for treatment of supraventricular tachycardias. Methods Retrospective analysis included CA procedure between April 2014 and May 2019. Five hundred and thirteen (513) patients were selected for analysis; they had confirmed diagnosis of atrioventricular nodal reentry tachycardia (AVNRT) or atrioventricular reentry tachycardia (AVRT). Patients were divided into two groups based on the use of fluoroscopy (conventional approach group - CG; zero-fluoroscopy group - ZF). Procedural data and clinical outcomes were analyzed. Two groups were compared using chi-squared test or Mann-Whithney U test when appropriate. Results There were 249 patients (44.2% males) in CG group, and 260 patients (47.5% males) in ZF group. ZF group included 113 (43.5%) pediatric patients. The groups differed in mean age (53.4 ± 16.4 years vs 30.0 ± 19.8 years (CG vs ZF), p &amp;lt; 0.001), postprocedural use of antiarrhythmic agents or beta blockers (55.3% vs 17.0% (CG vs ZF), p &amp;lt; 0.001) and type of arrhythmia (72.3% vs 60.6% AVNRT (CG vs ZF), p = 0.003). In CG group, all procedures were performed using radiofrequency (RF) energy, whereas in ZF group, cryoablation was used in 18.3% of procedures at the discretion of the operator. Mean procedural duration was longer in CG group (100.1 ± 48.8 vs 90.4 ± 83.0 minutes, p &amp;lt; 0.001). The mean fluroscopy time was 13.6 ± 9.3 minutes and mean dose area product was 554.1 ± 713.6 mGycm2 in the CG group. Acute success rate was higher in CG group (95.7 vs 90.7%, p = 0.027). However, the arrhythmia-free survival rate after 13.8 ± 11.0 months of follow-up was lower in the CG group (90.9 vs 96.5%, p = 0.009). Mean number of procedures per patient was 1.04 in the CG group and 1.14 in the ZF group (p &amp;lt; 0.001). There were no severe complications. Conclusions Zero-fluoroscopy CA of supraventricular tachycardias is associated with lower procedural success rate, but higher long-term arrhythmia-free survival rate when compared to conventional fluoroscopy guided procedures. It is possible, that these differences are stemming from somewhat different patient populations in both groups.

Evaluation of pre-hospital use of a valsalva assist device in the emergency treatment of supraventricular tachycardia [EVADE]: a randomised controlled feasibility trial

BackgroundThe valsalva manoeuvre is an internationally recommended initial treatment for supraventricular tachycardia (SVT). The pre-hospital use of a valsalva assist device, to help deliver this manoeuvre, could improve cardioversion rates and reduce the need for patients to attend hospital.MethodsWe conducted a randomised controlled feasibility trial comparing ambulance clinician use of a valsalva assist device versus standard care to treat adult patients presenting to an ambulance service in the south west of England. Eligible consenting participants were randomised 1:1 to device or standard care with trial procedures mirroring a proposed definitive trial.Feasibility was assessed upon ambulance clinician and participant recruitment rates and feedback, data completeness and potential future primary outcome rates.ResultsOver a 6 months period (1 July to 31 December 2018), 276 (23%) of 1183 eligible ambulance clinicians were trained and they recruited 34 participants; approximately 10% of patients presenting with suspected SVT during that time. Seventeen participants were randomised to each arm and all underwent their allocated valsalva strain method. All trial data and 63/68 (93%) of pre and post-valsalva ECGs were available. Seven (21%) participants had ineligible initial rhythms on retrospective expert ECG review. Valsalva assist device use was associated with cardioversion and non-conveyance in 4 (24%) and 2 (12%) participants respectively. No participants assigned to standard care were cardioverted and all were conveyed. Participant feedback highlighted the challenges of retaining trial information during an SVT attack.ConclusionsThe trial achieved efficient clinician training, randomisation and data collection, and there was an encouraging effect signal associated with device use. However, trial design changes should be considered to address the relatively small proportion of eligible patients recruited and challenges identified with consent and confirmation of cardioversion as a primary outcome.Trial registrationThe trial was registered with ClinicalTrials.gov (NCT03514628) on 2 May 2018.

Treatment of Supraventricular Tachycardia in Patients With Non-cardiac Surgery by Dexmedetomidine

Treatment of Supraventricular Tachycardia in Patients With Non-cardiac Surgery by Dexmedetomidine