Regular Supraventricular Tachycardia Research Articles

Two decades of SVT ablation in Denmark: a trend towards higher age, more comorbidity, and less prior use of antiarrhythmic and rate-limiting pharmacotherapy—a nationwide registry-based Danish study

Background and aimsTrends in patient selection and use of pharmacotherapy prior to catheter ablation (CA) for supraventricular tachycardia (SVT) are not well described. This study examined temporal trends in patients undergoing first-time CA for regular SVT, including atrioventricular nodal re-entry tachycardia (AVNRT), accessory pathways (APs), and ectopic atrial tachycardia (EAT) on a nationwide scale in Denmark in the period 2001–2018.Methods and resultsUsing Danish Nationwide registers, 9959 patients treated with first-time CA for SVT between 2001 and 2018 were identified, of which 6023 (61%) received CA for AVNRT, 2829 (28%) for AP, and 1107 (11%) for EAT. Median age was 55, 42, and 55 in the AVNRT, APs, and EAT group, respectively. The number of patients receiving CA increased from 1195 between 2001 and 2003 to 1914 between 2016 and 2018. The percentage of patients with a CHA2DS2-VASc score ≥ 2 increased in all patient groups. The number of patients who underwent CA with no prior use of antiarrhythmic- or rate limiting medicine increased significantly, though prior use of beta-blockers increased for AVNRT patients. Use of verapamil decreased in all three SVT groups (P < 0.05). Use of amiodarone and class 1C antiarrhythmics remained low, with the highest usage among EAT patients.ConclusionBetween 2001 and 2018, CA was increasingly performed in patients with SVT, primarily AVNRT- and EAT patients. The burden of comorbidities increased. Patients undergoing CA without prior antiarrhythmic- or rate-limiting drug therapy increased significantly. Use of beta-blockers increased and remained the most widely used drug.Graphical

Abstract 16852: Pathological ECG Findings in 24-h-Holter-ECGs in Patients With Ischemic Stroke

Introduction: ECG-monitoring covering several days is recommended by current guidelines to detect atrial fibrillation (AF) and other arrhythmias in stroke patients. In practice, the extent of rhythm monitoring varies. Here, we use data from the 24-hour screening-Holter-ECGs of the ongoing randomized multicenter trial Find-AF 2 to assess the rate of AF and other arrhythmias. Methods and Results: Find-AF 2 (NCT04371055) is a randomized and controlled open-label parallel multicenter trial with central AF adjudication (intervention arm) and blinded endpoint assessment. Patients ≥60 years with recent (≤30 days) ischemic strokes according to the AHA/ASA definition of any etiology are screened for eligibility. All eligible patients receive a 24-hour Holter-ECG prior to randomization. Holter ECG data are analyzed by the core laboratory using dedicated analysis software and following a predefined standard operation procedure. In this analysis, we included all 24-hour Holter-ECGs up to June 1, 2023. We analyzed 3742 24-hour-Holter-ECGs from 51 different centers and found new arrhythmias in 120 patients (3.2%). AF was detected in 61 patients (1.6%) with a median duration of the longest episode of 730 minutes [interquartile range (IQR) 220;1180] (see Figure 1). This led to the initiation of anticoagulation in all 61 patients (100%). In 47 patients (1.3%), pauses &gt;2.5 s (mean 3.1s±0.5s; longest pause 4.8s) or relevant bradycardias &lt;40 bpm were diagnosed. This resulted in the implantation of pacemakers in six patients. Finally, we found regular supraventricular tachycardias in 25 patients (0.7%; median duration 7.0 min [IQR 1.0;21.3]) - 24 of them had focal atrial tachycardias and one an AVNRT. Conclusion: Overall, 3.2% of ischemic stroke patients had pathological ECG findings, leading to a therapeutic change in 56%, most commonly anticoagulation for AF detection The number needed to screen for a change in medical management was 56.

The History of Atrial Flutter Electrophysiology, from Entrainment to Ablation: A 100-Year Experience in the Precision Electrocardiology.

Atrial flutter (AFL) is a regular supraventricular reentrant tachycardia generating a continuous fluttering of the baseline electrocardiography (ECG) at a rate of 250 to 300 beats per minute. AFL is classified based on the involvement of the cavo-tricuspid isthmus in the circuit. The "isthmic" (or type 1) AFL develops entirely in the right atrium; this circuit is commonly activated in a counter-clockwise direction, generating the common sawtooth ECG morphology in the inferior leads (slow descendent-fast ascendent). AFL can be nonisthmus dependent (type 2), often presenting with faster atrial rate and most commonly a left atrial location.

Predictors of AVNRT Recurrence After Slow Pathway Modification.

Atrioventricular nodal reentry tachycardia (AVNRT) is the most common regular supraventricular tachycardia (SVT). Slow pathway modification (SPM) is the accepted first line treatment with reported success rates around 95%. Information regarding possible predictors of AVNRT recurrence is scarce.Out of 4170 consecutive patients with SPM in our department from 1993-2018, we identified 78 patients (1.9%) receiving > 1 SPM (69% female, median age 50 years) with a recurrence of AVNRT after a successful SPM. We matched these patients for age, gender and number of radiofrequency applications during first SPM with 78 patients who received one successful SPM in our center without AVNRT recurrence. Both groups were analyzed for possible predictors of a recurrence of AVNRT during long-term follow-up. The recurrence group contained a significantly lower proportion of patients with an occurrence of junctional beats during SPM (69% versus 89%, P = 0.006). Moreover, significantly more cases of previously diagnosed atrial fibrillation/tachycardia (AF/AT; 21% versus 5%, P = 0.007) and inducible AF/AT during electrophysiology study (23% versus 6%, P = 0.006) were present in the recurrence group. While more than half of patients had a recurrence within the first year, in 20% symptoms reappeared ≥ 4 years after ablation.In a small percentage of patients, AVNRT recurs after an initially successful ablation. Interestingly, these patients had significantly fewer junctional beats during ablation and a higher rate of other (inducible) arrhythmias. AVNRT recurrence spanned a considerable timeframe and should remain a differential diagnosis, even years after ablation.

Clinical Presentation of Sustained Monomorphic Ventricular Tachycardia Without Cardiac Arrest.

Background“Palpitations” are one of the most common complaints prompting medical attention. Textbooks of medicine and cardiology as well as guideline documents and position papers describe palpitations as a common symptom of ventricular tachycardia (VT). However, data to support this description are lacking. The aim of our study was to evaluate the symptomatology of sustained monomorphic VT with emphasis on the prevalence of palpitations.Methods and ResultsConsecutive patients presenting to our center with a first event of a regular sustained monomorphic VT (n=59) or a regular supraventricular tachycardia (SVT; n=109) between January 2012 and September 2019 were interviewed regarding their symptoms during the arrhythmic event. We included only patients with a first arrhythmic event to avoid the influence of previous medical encounters on our patients’ terminology. As expected, patients with VT were older (age 68.8±13.6 versus 52.6±16.8 years; P<0.001), more often of male sex (94.9% versus 37.6%; P<0.001), had lower left ventricular ejection fraction (37±11% versus 59±2%, P<0.001) and more comorbidities (87.6% versus 40.5%; P<0.001) compared with patients with SVT. Importantly, even though the heart rate upon presentation did not differ between the 2 groups (165±26 beats/min during VT versus 171±32 beats/min during SVT; P=0.16), symptomatology differed significantly; specifically, palpitations were reported in only 8.8% of VT patients, compared with 90.7% of SVT patients (P<0.001). Common symptoms in the VT group included chest pain (64%), dyspnea (21%), and dizziness (26%).ConclusionsDespite similar heart rate, patients with VT rarely report having palpitations, whereas patients with SVT do so commonly. This finding may assist with decision making in patients reporting palpitations in whom an ECG tracing is not available.

A Study of Narrow Qrs Tachycardia With Emphasis On the Clinical features, ECG, electrophysiology/radiofrequency Ablation

Aim: Atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT) are the most common forms of paroxysmal regular supraventricular tachycardias. Materials & methods: The clinical, ECG and electrophysiological findings of 121 patients with narrow QRS tachycardia were evaluated prospectively. Results: A total of 75 (62%) of the patients had AVNRT while 46 (38%) had AVRT. Pounding sensation in the neck (40 vs 15.2%; p = 0.004), presynope (26.7 vs 56.5%; p =0.001) identifiable P wave after QRS complex (25.3 vs 73.9%; p = 0.001), pseudo r'/s waves (45.3 vs 4.3%; p = 0.001), limb leads ST-T changes (34.7 vs 60.9%; p = 0.004) were the significant changes observed. A total of 94.7% of AVNRT and 87% of AVRT could be diagnosed correctly considering both clinical and ECG criteria. Conclusion: Pounding sensation in the neck and presyncope along with ECG features like identifiable P wave after QRS complex, pseudo r'/s waves and limb lead ST-T changes very accurately differentiate AVNRT and AVRT.

P2856Risk factors for the first and second inappropriate implantable cardioverter-defibrillator therapy: a subanalysis of the NIPPON storm study

Abstract Background Implantable cardioverter-defibrillator (ICD) including cardiac resynchronization therapy with defibrillator (CRT-D) has become an established therapeutic option to reduce the risk of sudden cardiac death. However, there are risks for the first and second inappropriate ICD shock events, which have not been well clarified. Objective To clarify the risk factors for the first and second inappropriate ICD therapy events. Methods We conducted a post-hoc, secondary analysis of the data from a multicenter, prospective, observational study (the Nippon Storm Study), designed to clarify the risk factors for electrical storm. The analysis included the data of 1549 of the 1570 patients with ICD or CRT-D enrolled into the study. An inappropriate event was defined as any inappropriate ICD or CRT-D therapy delivered, including antitachycardia pacing (ATP) or ICD shock for sinus tachycardia, atrial fibrillation (AF)/ atrial flutter (AFL), regular supraventricular tachycardia, or for non-arrhythmic events Results Over a median follow-up of 28 months, 293 inappropriate ICD therapy events occurred in 153 of the 1549 patients (10.0%) in the study sample, with 106 inappropriate ICD shock events identified in 72 (4.6%) patients. Inappropriate therapy events were unlikely during sleep. On multivariate Cox regression analysis, the risk factors for the first inappropriate ICD therapy included, younger age (hazard ratio (HR), 0.986; 95% confidence interval (CI), 0.973–0.998; p=0.028), AF/AFL (AF/AFL; HR, 2.324; 95% CI, 1.372–3.939; p=0.002), ICD implantation (HR, 2.377; 95% CI, 1.332–4.244; p=0.004), and multiple versus single stimulation zone (HR, 1.852; 95% CI, 1.163–2.951, p=0.010). After the first inappropriate ICD therapy event, any interventions were performed, including a change in the ICD programming (n=122), initiation or change in medication (n=33) and catheter ablation (n=7), or a combination of interventions. The rate of the second inappropriate ICD therapy event after treatment of the first was 37.6% at one year. The patients who underwent an intervention after the first inappropriate ICD event showed a lower risk of the second event, compared to those without any intervention (1.0% versus 6.0% at one week, 4.2% versus 22.3% at one month, 27.3% versus 57.4% at one year, log-rank p&lt;0.001). On multivariate Cox regression analysis, the risk factors for the second inappropriate ICD therapy was no-intervention after the first inappropriate ICD therapy (HR, 3.521; 95% CI, 1.773–6.993; p=0.001). Conclusions The risk for the first inappropriate ICD therapy increased for younger patients, use of ICD versus CRT-D and a prior history of AF/AFL. Intervention after the first inappropriate ICD therapy could reduce the risk of the second inappropriate event.

When and howdoes a single ventricular premature beat initiate and terminate supraventricular tachycardia?

The differential diagnosis of a supraventricular tachycardia (SVT) is accomplished using a number of pacing maneuvers. The incidence and mechanism of a single ventricular premature beat (VPB) on initiation and termination of tachycardia were evaluated during programmed electrical stimulation (PES) of the heart in patients with the two most common regular SVTs: atrioventricular re-entrant tachycardia (AVNRT) and orthodromic atrioventricular tachycardia (AVRT). Three hundred and thirty-seven consecutive patients aged above 18years with an inducible sustained AVNRT or AVRT were prospectively enrolled. Patients with more than one tachyarrhythmia mechanism were excluded. Two hundred and seventeen patients (64.4%) had typical slow/fast AVNRT and 120 (35.6%) had an orthodromic AVRT using a rapidly conducting accessory pathway for V-A conduction. In this cross-sectional study, we specifically report the analysis of tachycardia induction and termination by a single VPB. Tachycardia induction with a single VPB during sinus rhythm was seen in 7 of 120 AVRT and in only one of the 217 patients with AVNRT, (5.8% vs. 0.3%, p<0.05). When a single VPB was delivered during basic ventricular pacing these values were 28% versus 4%, respectively, (p<0.001). Termination of tachycardia by a single VPB was observed in nine (4.1%) patients with AVNRT and in 57 (47.5%) with AVRT (p<0.001). Initiation of SVT by a single VPB during sinus rhythm was uncommon and favored AVRT. Termination of SVT by a single VPB was commonly seen in AVRT but rarely in AVNRT. These findings can be of help when interpreting a noninvasive arrhythmia event recording.

Atrial fibrillation inducibility after pulmonary vein isolation under general anaesthesia.

Atrial fibrillation (AF) inducibility with rapid atrial pacing following AF ablation is associated with higher risk of AF recurrence. The predictive value of AF inducibility in paroxysmal AF patients after pulmonary vein isolation (PVI), done under general anaesthesia (GA), remains questionable since GA might alter AF inducibility and/or sustainability. Consecutive patients (n = 120) with paroxysmal AF without prior catheter ablation (CA) were enlisted in the study. All patients were ablated under GA. We have used a point-by-point CA and elimination of dormant conduction after adenosine in all patients. A predefined stimulation protocol was used to induce arrhythmias after PVI. Regular supraventricular tachycardias were mapped and ablated. Patients were divided into 3 subgroups - noninducible, inducible AF with spontaneous termination in five minutes, inducible AF without spontaneous termination. During 12 months of follow-up, all patients were examined four-times with 7-day ECG recordings. There was no statistical difference between the three subgroups in a rate of arrhythmia recurrence (11.1 vs. 27.5 vs. 27.3%, P=0.387), despite a clear trend to a better success rate in the non-inducible group. The subgroups did not differ in left atrial (LA) diameter (41.0±6, 43.0±7, 42.0±5 mm, P=0.962) or in any other baseline parameter. AF inducibility as well as presence or absence of its early spontaneous termination after PVI done under general anaesthesia in paroxysmal AF patients were not useful as predictors of procedural failure.

Risk of cardiac arrhythmias after electrical accident: a single-center study of 480 patients

ObjectivePatients with electrical injury are considered to be at high risk of cardiac arrhythmias. Due to the small number of studies, there is no widely accepted guideline regarding the risk assessment and management of arrhythmic complications after electrical accident (EA). Our retrospective observational study was designed to determine the prevalence of ECG abnormalities and cardiac arrhythmias after EA, to evaluate the predictive value of cardiac biomarkers for this condition and to assess in-hospital and 30-day mortality.MethodsConsecutive patients presenting after EA at the emergency department of our institution between 2011 and 2016 were involved in the current analysis. ECG abnormalities and arrhythmias were analyzed at admission and during ECG monitoring. Levels of cardiac troponin I, CK and CK-MB were also collected. In-hospital and 30-day mortality data were obtained from hospital records and from the national insurance database.ResultsOf the 480 patients included, 184 (38.3%) had suffered a workplace accident. The majority of patients (96.2%) had incurred a low-voltage injury (< 1000 V). One hundred and four (21.7%) patients had a transthoracic electrical injury while 13 (2.7%) patients reported loss of consciousness. The most frequent ECG disorders at admission were sinus bradycardia (< 60 bpm, n = 50, 10.4%) and sinus tachycardia (> 100 bpm, n = 21, 4.4%). Other detected arrhythmias were as follows: newly diagnosed atrial fibrillation (n = 1); frequent multifocal atrial premature complexes (n = 1); sinus arrest with atrial escape rhythm (n = 2); ventricular fibrillation terminated out of hospital (n = 1); ventricular bigeminy (n = 1); and repetitive nonsustained ventricular tachycardia (n = 1). ECG monitoring was performed in 182 (37.9%) patients for 12.7 ± 7.1 h at the ED. Except for one case with regular supraventricular tachycardia terminated via vagal maneuver and one other case with paroxysmal atrial fibrillation, no clinically relevant arrhythmias were detected during the ECG monitoring. Cardiac troponin I was measured in 354 (73.8%) cases at 4.6 ± 4.3 h after the EA and was significantly elevated only in one resuscitated patient. CK elevation was frequent, but CK-MB was under 5% in all patients. Both in-hospital and 30-day mortality were 0%.ConclusionsMost of cardiac arrhythmias in patients presenting after EA can be diagnosed by an ECG on admission, thus routine ECG monitoring appears to be unnecessary. In our patient cohort cardiac troponin I and CK-MB were not useful in risk assessment after EA. Late-onset malignant arrhythmias were not observed.

Dysrhythmias in patients with a complete atrioventricular septal defect: From surgery to early adulthood.

ObjectiveOutcomes after surgical repair of complete atrioventricular septal defect (cAVSD) have improved. With advancing age, the risk of development of dysrhythmias may increase. The aims of this study were to (1) examine development of sinus node dysfunction (SND), atrial and ventricular tachyarrhythmias, and (2) study progression of atrioventricular conduction abnormalities in young adult patients with repaired cAVSD.Study designIn this retrospective multicenter study, 74 patients (68% female) with a cAVSD repaired in childhood were included. Patients’ medical files were evaluated for occurrence of SND, atrioventricular conduction block (AVB), atrial and ventricular tachyarrhythmias.ResultsMedian age at repair was 6 months (interquartile range 3‐10) and median age at last follow‐up was 24 years (interquartile range 21‐28). SND occurred after a median of 17 years (interquartile range 11‐19) after repair in 23% of patients, requiring pacemaker implantation in two patients (12%). Regular supraventricular tachycardia was observed in three patients (4%). Atrial fibrillation and ventricular tachyarrhythmias were not observed. Twenty‐seven patients (36%) had first‐degree AVB, which was self‐limiting in 16 (59%) and persistent in 10 (37%) patients. One patient developed third‐degree AVB 7 days after left atrioventricular valve replacement. Spontaneous type II second‐degree AVB occurred in a 28‐year‐old patient. Both patients underwent pacemaker implantation.ConclusionsClinically significant dysrhythmias were uncommon in young adult patients after cAVSD repair. However, three patients required pacemaker implantation for either progression of SND or spontaneous type II second‐degree AVB. Longer follow‐up should point out whether dysrhythmias will progress or become more prevalent with increasing age.

Irregularity and lack of p waves in short tachycardia episodes predict atrial fibrillation and ischemic stroke

Atrial fibrillation (AF) is defined as an irregular supraventricular tachycardia (SVT) without p waves, with duration >30 seconds. Whether AF characteristics during short SVT episodes predict AF and stroke is not known. The purpose of this study was to determine whether irregularity and lack of p waves, alone or in combination, during short SVT episodes increase the risk of incident AF and ischemic stroke. The population-based Malmö Diet and Cancer study includes 24-hour ECG screening of 377 AF-free individuals (mean age 64.5 years; 43% men) who were prospectively followed for >13 years. There were 65 AF events and 25 ischemic stroke events during follow-up. Subjects with an SVT episode ≥5 beats were identified, and the longest SVT episode was assessed for irregularity and lack of p waves. The association between SVT classification and AFand stroke was assessed using multivariable adjusted Cox regression. The incidence of AF increased with increasing abnormality of the SVTs. The risk-factor adjusted hazard ratio for AF was 4.95 (95% confidence interval 2.06-11.9; P <.0001) for those with short irregular SVTs (<70 beats) without p waves. The incidence of ischemic stroke was highest in the group with regular SVT episodes without p waves (hazard ratio 14.2; 95% confidence interval 3.76-57.6; P <.0001, adjusted for age and sex). Characteristics of short SVT episodes detected at 24-hour ECG screening are associated with incident AF and ischemic stroke. Short irregular SVTs without p waves likely represent early stages of AF or atrial myopathy. Twenty-four-hour ECG could identify subjects suitable for primary prevention efforts.

P827Zero-fluoroscopy approach as the gold standard for catheter ablation of regular supraventricular tachycardias - experience beyond 1500 procedures

P827Zero-fluoroscopy approach as the gold standard for catheter ablation of regular supraventricular tachycardias - experience beyond 1500 procedures

Safety and efficacy of paramedic treatment of regular supraventricular tachycardia: a randomised controlled trial

IntroductionSupraventricular tachycardias (SVTs) are a common cause of acute hospital presentations. Adenosine is an effective treatment. To date, no studies have directly compared paramedic-with hospital-delivered treatment of acute SVT with...

Supraventricular tachycardias: differential diagnosis at bedside and in the electrophysiology laboratory

AbstractClinical and electrophysiologic criteria used for the differential diagnosis of regular supraventricular tachycardias (SVT) are presented. Although several electrocardiographic clues may assist differential diagnosis, this is usually accomplished at electrophysiology study and, most often, is between atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia due to a concealed accessory pathway, and atrial tachycardia. Atrial and, mainly, ventricular pacing maneuvers during sinus rhythm or tachycardia have been used with variable success rate. In clinical practice, these techniques cannot be applied to all cases, and multiple criteria have to be used for the differential diagnosis of narrow complex tachycardias with atypical characteristics.Answer questions and earn CME: https://wileyhealthlearning.com/Activity2/4469457/Activity.aspx

Risk Stratification for Arrhythmic Events in Patients With Asymptomatic Pre-Excitation: A Systematic Review for the 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society.

To review the literature systematically to determine whether noninvasive or invasive risk stratification, such as with an electrophysiological study of patients with asymptomatic pre-excitation, reduces the risk of arrhythmic events and improves patient outcomes. PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (all January 1, 1970, through August 31, 2014) were searched for randomized controlled trials and cohort studies examining noninvasive or invasive risk stratification in patients with asymptomatic pre-excitation. Studies were rejected for low-quality design or the lack of an outcome, population, intervention, or comparator of interest or if they were written in a language other than English. Of 778 citations found, 9 studies met all the eligibility criteria and were included in this paper. Of the 9 studies, 1 had a dual design-a randomized controlled trial of ablation versus no ablation in 76 patients and an uncontrolled prospective cohort of 148 additional patients-and 8 were uncontrolled prospective cohort studies (n=1594). In studies reporting a mean age, the range was 32 to 50 years, and in studies reporting a median age, the range was 19 to 36 years. The majority of patients were male (range, 50% to 74%), and <10% had structural heart disease. In the randomized controlled trial component of the dual-design study, the 5-year Kaplan-Meier estimates of the incidence of arrhythmic events were 7% among patients who underwent ablation and 77% among patients who did not undergo ablation (relative risk reduction: 0.08; 95% confidence interval: 0.02 to 0.33; P<0.001). In the observational cohorts of asymptomatic patients who did not undergo catheter ablation (n=883, with follow-up ranging from 8 to 96 months), regular supraventricular tachycardia or benign atrial fibrillation (shortest RR interval >250 ms) developed in 0% to 16%, malignant atrial fibrillation (shortest RR interval ≤250 ms) in 0% to 9%, and ventricular fibrillation in 0% to 2%, most of whom were children in the last case. The existing evidence suggests risk stratification with an electrophysiological study of patients with asymptomatic pre-excitation may be beneficial, along with consideration of accessory-pathway ablation in those deemed to be at high risk of future arrhythmias. Given the limitations of the existing data, well-designed and well-conducted studies are needed.

Differential diagnosis of regular, narrow-QRS tachycardias.

We present an update on clinical and electrophysiological criteria used for the differential diagnosis of regular supraventricular tachycardias. Although several electrocardiographic clues may assist in the differential diagnosis, this is usually accomplished at electrophysiology study, and most often, the differential diagnosis is between atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia due to a concealed accessory pathway, and atrial tachycardia. Atrial and ventricular pacing maneuvers during sinus rhythm or tachycardia have been used with various success rates. In clinical practice, these techniques cannot be applied to all cases, and multiple criteria must be used for the differential diagnosis of narrow-complex tachycardias with atypical characteristics.

0039: Elderly patients benefit from the evaluation of their tachycardia

Too often, tachycardias of elderly patients are medically treated without evaluation of their mechanism. The purpose of the study was to look for the influence of age on clinical and electrophysiological data and long-term follow-up of patients with paroxysmal supraventricular tachycardia (SVT). SVT was induced in 1690 patients, 996 females, mean age 49±19 years referred for regular tachycardia. Clinical history, SVT-related complications, echocardiography, results of electrophysiological study, methods of treatment were collected. 269 patients with SVT were aged from 70 to 97 years (group I),188 from 70 to 79 (group IA) and 81 from 80 to 97 (group IB). Anticoagulants were prescribed in 23 for an erroneous diagnosis of atrial tachycardia. They were compared to 1421 patients <70 years (group II). Heart disease was more frequent in group I (26%) (group IA:30%, group IB:18%) than in group II (9%) (p<0.0001). Atypical and typical AV node reentrant tachycardia were more frequent in group I (94%) than in group II (80%) and concealed accessory pathway was less frequent in group I (6%, Group IA:7%, IB:5%) than in group II (20%). SVT-related adverse events were more frequent in group I (26%) (p<0.0001) (group IA:25%, group IB:29%) than in group II (11%). During follow-up (3±3 years), SVT ablation was indicated more frequently in group I (73%) (p<0.002) (group IA:73%, group IB:72%) than in group II (62.5%). SVT ablation-related complications were more frequent in group IB:7%) (p<0.011) than in group I (3.5%) or IA (4%). Late occurrence of atrial fibrillation (AF) was more frequent in group IA (10%) than in group II (5%) (p<0.04) (NS for the group IB (5%). Cardiac deaths were more frequent in group I (6%) (group IA:4%, group IB: 7.5%) than in group II (2%) (p<0.001). SVT-related adverse presentation was frequent in elderly patients. We recommend the evaluation of regular SVT’s because they can be related to AVNRT/AVRT. Curative treatment of these tachycardias can be done despite a risk of ablation-related major complications more frequent after 79 years and a risk of AF development and cardiac death higher in elderly patients than in younger patients.

Feasibility of Implementation of a “Simplified, No‐X‐Ray, No‐Lead Apron, Two‐Catheter Approach” for Ablation of Supraventricular Arrhythmias in Children and Adults

Although the "near-zero-X-Ray" or "No-X-Ray" catheter ablation (CA) approach has been reported for treatment of various arrhythmias, few prospective studies have strictly used "No-X-Ray," simplified 2-catheter approaches for CA in patients with supraventricular tachycardia (SVT). We assessed the feasibility of a minimally invasive, nonfluoroscopic (MINI) CA approach in such patients. Data were obtained from a prospective multicenter CA registry of patients with regular SVTs. After femoral access, 2 catheters were used to create simple, 3D electroanatomic maps and to perform electrophysiologic studies. Medical staff did not use lead aprons after the first 10 MINI CA cases. A total of 188 patients (age, 45 ± 21 years; 17% <19 years; 55% women) referred for the No-X-Ray approach were included. They were compared to 714 consecutive patients referred for a simplified approach using X-rays (age, 52 ± 18 years; 7% <19 years; 55% women). There were 9 protocol exceptions that necessitated the use of X-rays. Ultimately, 179/188 patients underwent the procedure without fluoroscopy, with an acute success rate of 98%. The procedure times (63 ± 26 vs. 63 ± 29 minutes, P > 0.05), major complications (0% vs. 0%, P > 0.05) and acute (98% vs. 98%, P > 0.05) and long-term (93% vs. 94%, P > 0.05) success rates were similar in the "No-X-Ray" and control groups. Implementation of a strict "No-X-Ray, simplified 2-catheter" CA approach is safe and effective in majority of the patients with SVT. This modified approach for SVTs should be prospectively validated in a multicenter study.

Exclusion of Fluoroscopy Use in Catheter Ablation Procedures: Six Years of Experience at a Single Center

Nonfluoroscopic mapping systems have demonstrated significant reduction of radiation exposure in radiofrequency (RF) catheter ablation procedures. However, their use as only imaging guide is still limited. To evaluate the usefulness of a completely nonfluoroscopic approach to catheter ablation of supraventricular arrhythmias using the Ensite-NavX™ electroanatomical navigation system. During 6 years, all consecutive patients referred for RF catheter ablation of regular supraventricular tachycardia (SVT) were admitted for a "zero-fluoroscopy" approach and studied prospectively. The only exclusion criterion was the need to perform a transseptal puncture. A total of 340 procedures were performed on 328 patients (179 men, age 55.7 ± 18.6 years). One hundred fifty-three patients had typical atrial flutter (AFL), 146 had AV nodal reentrant tachycardia (AVNRT), 35 had AV reciprocating tachycardia (AVRT), 4 patients had incisional atrial flutter (IAF), and 2 had focal atrial tachycardia (AT). Procedural success was achieved in 337 of the cases (99.1%). In 322 (94.7%), the procedure was completed without any fluoroscopy use. Mean procedure time was 110.5 ± 51.8 minutes. Mean RF application time was 9.8 ± 12.8 minutes and the number of RF lesions was 16.43 ± 15.8. Only 1 major complication related to vascular access was recorded. During follow-up, there were 12 recurrences (3.5%) (8 patients from the AVNRT group, 4 patients from the AP group). RF catheter ablation of SVT with an approach completely guided by the NavX system and without use of fluoroscopy is feasible, safe, and effective.