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.

Atypical Fast-Slow Atrioventricular Nodal Reentrant Tachycardia Incorporating a "Superior" Slow Pathway: A Distinct Supraventricular Tachyarrhythmia.

BACKGROUND: The existence of an atypical fast-slow (F/S) atrioventricular nodal reentrant tachycardia (AVNRT) including a superior (sup) pathway with slow conductive properties and an atrial exit near the His bundle has not been confirmed. METHODS AND RESULTS: We studied 6 women and 2 men (age, 74 ± 7 years) with sup-F/S-AVNRT who underwent successful radiofrequency ablation near the His bundle. Programmed ventricular stimulation induced retrograde conduction over a superior SP with an earliest atrial activation near the His bundle, a mean shortest spike-atrial interval of 378 ± 119 milliseconds, and decremental properties in all patients. sup-F/S-AVNRT was characterized by a long-RP interval; a retrograde atrial activation sequence during tachycardia identical to that over a sup-SP during ventricular pacing; ventriculoatrial dissociation during ventricular overdrive pacing of the tachycardia in 5 patients or atrioventricular block occurring during tachycardia in 3 patients, excluding atrioventricular reentrant tachycardia; termination of the tachycardia by ATP; and a V-A-V activation sequence immediately after ventricular induction or entrainment of the tachycardia, including dual atrial responses in 2 patients. Elimination or modification of retrograde conduction over the sup-SP by ablation near the right perinodal region or from the noncoronary cusp of Valsalva eliminated and confirmed the diagnosis of AVNRT in 4 patients each. CONCLUSIONS: sup-F/S-AVNRT is a distinct supraventricular tachycardia, incorporating an SP located above the Koch triangle as the retrograde limb, that can be eliminated by radiofrequency ablation.

ANXIETY LEVELS IN PATIENTS WITH PAROXY-SMAL SUPRAVENTRICULAR TACHYCARDIA IN RELATION WITH THE PATIENT DEMOGRAPHICS, TYPE OF SUPRAVENTRICULAR TACHYCARDIA AND THEIR PERSONALITY TYPE.

The aim of the study was to evaluate the incidence of different personality types and state and trait anxiety levels in patients with paroxysmal supraventricular tachycardia and their association with patients age, gender and the mechanism of the paroxysmal SVT. 62 patients with documented paroxysmal supraventricular tachycardia who underwent endocardial eletrophysiological study and catheter ablation of the paroxysmal SVT were included in the study. The patients were asked to fill out the Myers-Brigss Type Indicator and State-Trait Anxiety Inventory questionnaires and the results were analyzed and correlated with the arrhythmia mechanism determined during electrophysiological study and catheter ablation procedure, and the patients' demographics (age and gender). There was no significant difference in State (mean 41.53±13.51, p=0.893) or Trait (mean 44.70±12.62, p=0.315) anxiety scores according to gender although higher scores were found in females. Older patients (≥50 years old compared to <50 years old) had higher anxiety scores but with no statistical significance (p=0.344 for state anxiety and p=0.100 for trait anxiety). The patients with AVNRT had significantly higher Trait anxiety scores (mean 46.82±10.52) than the patients with AVRT or AT (mean 40.59±10.91) (p=0.032). State anxiety score was not significantly different between patients with different SVT types (p=0.706). Anxiety is an important factor to be considered in patients with paroxysmal supraventricular tachycardia. It doesn't seem to be associated with different personality types. Female and older patients tend to show higher anxiety levels. The atrioventricular Nodal Reentrant Tachycardia (AVNRT) is associated with significantly higher trait anxiety levels compared to other types of paroxysmal supraventricular tachycardia.

[An intelligent model for classifying supraventricular tachycardia mechanisms based on 12-lead wearable electrocardiogram devices].

OBJECTIVE: To develop an intelligent model for differential diagnosis of atrioventricular nodal re-entrant tachycardia (AVNRT) and atrioventricular re-entrant tachycardia (AVRT) using 12-lead wearable electrocardiogram devices. METHODS: A total of 356 samples of 12-lead supraventricular tachycardia (SVT) electrocardiograms recorded by wearable devices were randomly divided into training and validation sets using 5-fold cross validation to establish the intelligent classification model, and 101 patients with the diagnosis of SVT undergoing electrophysiological studies and radiofrequency ablation from October, 2021 to March, 2023 were selected as the testing set. The changes in electrocardiogram parameters before and during induced tachycardia were compared. Based on multiscale deep neural network, an intelligent diagnosis model for classifying SVT mechanisms was constructed and validated. The 3-lead electrocardiogram signals from Ⅱ, Ⅲ, and Ⅴ1 were extracted to build new classification models, whose diagnostic efficacy was compared with that of the 12-lead model. RESULTS: Of the 101 patients with SVT in the testing set, 68 were diagnosed with AVNRT and 33 were diagnosed with AVRT by electrophysiological study. The pre-trained model achieved a high area under the precision-recall curve (0.9492) and F1 score (0.8195) for identifying AVNRT in the validation set. The total F1 scores of the lead Ⅱ, Ⅲ, Ⅴ1, 3-lead and 12-lead intelligent diagnostic models in the testing set were 0.5597, 0.6061, 0.3419, 0.6003 and 0.6136, respectively. Compared with the 12-lead classification model, the lead-Ⅲ model had a net reclassification index improvement of -0.029 (P=0.878) and an integrated discrimination index improvement of -0.005 (P=0.965). CONCLUSION: The intelligent diagnostic model based on multiscale deep neural network using wearable electrocardiogram devices has an acceptable accuracy for classifying SVT mechanisms.

U22, a protocol to quantify symptoms associated with supraventricular tachycardia.

BACKGROUND: The main indication for ablation of supraventricular tachyarrhythmias (SVTA) is symptomatic relief. Specific paroxysmal symptoms cannot be quantified with general measures of quality of life, such as with the SF-36 questionnaire. U22 is a new protocol which measures the effects of arrhythmia on well-being, the intensity of discomfort during an episode, the type and temporal characteristics of dominant symptoms, and the duration and frequency of episodes. Discrete 0-10 scales are used. Unlike SF-36, U22 can be used in individual patients. METHODS: U22 and SF-36 protocols were used in the symptomatic evaluation of 88 patients (mean age = 49.6 +/- 16.4 years; 43 men), who underwent catheter ablation of SVTA. RESULTS: The U22 scores (SD) for (a) well-being (10 being best), (b) effects of arrhythmia on well-being (10 being worst), and (c) discomfort during arrhythmia (10 being worst) were 5.6 (2.7), 7.5 (2.8), and 8.0 (2.4), respectively. For comparison, the physical and mental component summaries of SF-36 were 45.3 (11.0) and 45.2 (12.1), respectively, slightly lower than the expected normal of 50. The intensity of dominant symptom scored by U22 was 9.7 (1.2), 10 being worst. In 29% of patients > or =4 symptoms were equally dominant. Multiple dominant symptoms in U22 were associated with a low general well-being in SF-36. CONCLUSION: We found U22 useful to quantify symptoms associated with SVTA.

Infraatrial supraventricular tachycardias: mechanisms, diagnosis, and management.

Tachycardias are traditionally classified as either ventricular tachycardia (VT) or supraventricular tachycardia (SVT). VT can be defined as a tachycardia which requires only ventricular structures for perpetuation. SVT is defined in terms of exclusion of VT and hence is any tachycardia which requires participation of at least one supraventricular structure for perpetuation. Certain SVTs require only participation of the atrioventricular node (AVN) and the His bundle (HB) but not the atrial myocardium or any of the great thoracic veins for perpetuation and hence can be described as "infraatrial." The three main mechanisms of infraatrial SVTs are: (1) intranodal atrioventricular reentrant tachycardia; (2) junctional ectopic tachycardia; and (3) nodoventricular reentrant tachycardia. The clinical significance of infraatrial SVTs is that they are compatible with any A:V ratio and even atrioventricular (AV) dissociation. Infraatrial SVTs are often suspected when a narrow complex tachycardia presents with apparent AV dissociation and a counterintuitive A:V ratio of < 1:1. However, if the same tachycardia is conducted with aberrant conduction or preexcitation, a broad complex tachycardia with an A:V ratio of < 1:1 will arise and that can be easily mistaken for VT. The possible patterns of electrical association and dissociation between different cardiac structures are examined, and how individual types of infraatrial SVT can be diagnosed and managed are reviewed.

Wide complex irregularly regular tachycardia with QRS alternation.

A 44-year-old white man was referred to our service because of a history of symptomatic rapid palpitations that had begun on January 2007. He had no previous history of syncope or family history of sudden cardiac death. The patient was otherwise well and had not been taking any medications. The electrocardiogram (ECG) recorded during sinus rhythm was within normal limits. A 12-lead ECG was performed during the last episode on July 2007 while he was working at his office. An irregular wide complex tachycardia with varying QRS morphology (left bundle-branch block with an alternating pattern) was documented. The differential diagnoses based on the 12-lead electrocardiogram (ECG) were supraventricular tachycardia with aberrant conduction and QRS alternans, atrial tachycardia with anterograde conduction over an accessory pathway, or ventricular tachycardia. An electrophysiology study was performed and the results are discussed.

Supraventricular tachycardia in the pediatric primary care setting: Age-related presentation, diagnosis, and management.

As many as 1 in 250 children experience supraventricular tachycardia (SVT), but its presentation is often vague and its symptoms mistakenly attributed to other common pediatric conditions. If SVT is correctly identified in a timely manner, most children will go on to live normal healthy lives. SVT is not covered in depth in most pediatric advanced practice nursing programs, but because of its prevalence, it should be familiar to all pediatric primary care providers. This article reviews common mechanisms of SVT and their age-related presentation, diagnosis, and management. A case study of an 8-year-old boy with SVT is presented.

Use of Programmed Ventricular Extrastimulus During Supraventricular Tachycardia to Differentiate Atrioventricular Nodal Re-Entrant Tachycardia From Atrioventricular Re-Entrant Tachycardia.

OBJECTIVES: This study hypothesized that early coupled ventricular extrastimuli (V2) stimulation might yield a more robust differentiation between atrioventricular nodal re-entrant tachycardia (AVNRT) and atrioventricular re-entrant tachycardia (AVRT). BACKGROUND: Programmed V2 during supraventricular tachycardia are useful to differentiate AVNRT from AVRT by subtracting the ventriculoatrial (VA) interval from the stimulus to atrial depolarization (stimulus atrial [SA]) interval, but all such maneuvers have limitations. METHODS: Patients with either AVNRT or AVRT were investigated. The entire tachycardia cycle length (TCL) was scanned with V2 delivered from the right ventricular apex. The SA-VA difference was calculated with V2 clearly resetting the tachycardia. The prematurity of V2 was calculated by dividing the coupling interval (CI) by the TCL. RESULTS: A total of 210 patients (102 with AVNRT) were included. The SA-VA difference was >70 ms in all AVNRT patients and was <70 ms in all AVRT patients with right and septal accessory pathways (APs), except for those with decremental APs, in whom there was an overlap between AVNRT and AVRT with left APs. However, a SA-VA difference >110 ms with a CI/TCL of <65% distinguished AVNRT from AVRT using the left AP, with sensitivity and specificity of 87% and 100%, respectively. Ventricular overdrive pacing resulted in tachycardia termination or AV dissociation in 28% of patients compared with 15% of patients using the V2 technique (p = 0.008). CONCLUSIONS: A SA-VA of >70 ms using the V2 technique differentiated AVNRT from AVRT using septal and right APs. Use of the V2 technique with a short CI differentiated AVNRT from AVRT using left APs. The V2 technique less frequently resulted in tachycardia termination compared with ventricular entrainment.

Supraventricular Arrhythmias: Clinical Framework and Common Scenarios for the Internist.

Supraventricular arrhythmias can cause uncomfortable symptoms for patients. Often, the first point of contact is in the primary care setting, and thus, it is imperative for the general internist to have a clinical framework in place to recognize this cluster of cardiac arrhythmias, be familiar with immediate and long-term management of supraventricular tachycardias, and understand when cardiac electrophysiologic consultation is necessary. The electrocardiographic characteristics can have subtle but important clues to the diagnosis and initial management. An understanding of the mechanisms of these arrhythmias is essential to provide proper therapy to the patient. In addition, there are common practice strategies that should be emphasized to avoid common misperceptions that could pose risk to the patient. In this review, we provide a framework to more easily recognize and classify these arrhythmias. We also illustrate the mechanism for these arrhythmias to provide an understanding of the interventions generally used.

Emergency department management of the pediatric patient with supraventricular tachycardia.

Supraventricular tachycardia (SVT) is the most common tachyarrhythmia that necessitates treatment in children. It is characterized by a rapid and regular heart rate, which generally exceeds 180 beats per minute in children and 220 beats per minute in adolescents. Supraventricular tachycardia results from conduction of electrical impulses along an accessory connection from the atrium to the ventricle (atrioventricular reentry tachycardias: orthodromic or antidromic) or conduction within the atrioventricular node (atrioventricular node reentry tachycardia). Emergency department management of SVT depends on the patient's clinical status. Treatment of a stable patient with SVT includes vagal maneuvers and adenosine, whereas treatment of an unstable patient requires synchronized cardioversion. This article presents an overview of the etiology, pathophysiology, and clinical presentation of SVT and discusses the emergency department management of an infant or child with SVT.

Appropriate and inappropriate ventricular therapies, quality of life, and mortality among primary and secondary prevention implantable cardioverter defibrillator patients: results from the Pacing Fast VT REduces Shock ThErapies (PainFREE Rx II) trial.

BACKGROUND: Implantable cardioverter defibrillators (ICDs) reduce mortality in primary and secondary prevention. Quality of life, mortality, appropriate therapies for specific ventricular rhythms, and inappropriate therapies for supraventricular tachycardia (SVT) were compared among 582 patients (primary prevention=248; secondary prevention=334) in PainFREE Rx II, a 634-patient prospective, randomized study of antitachycardia pacing or shocks for fast ventricular tachycardia (FVT). METHODS AND RESULTS: ICDs were programmed identically with 3 zones (ventricular tachycardia [VT] <188 bpm; FVT=188 to 250 bpm; ventricular fibrillation [VF] >250 bpm) but randomized to antitachycardia pacing or shock as initial therapy for FVT. All treated episodes with electrograms were adjudicated. Primary prevention patients had lower ejection fractions and more coronary artery disease. beta-Blocker use, antiarrhythmic drug use, and follow-up duration were similar. Over 11+/-3 months, 1563 treated episodes were classified as VT (n=740), FVT (n=350), VF (n=77), and SVT (n=396). The distribution of VT, FVT, and VF was not different between primary and secondary prevention patients (respectively, VT 52% versus 54%, FVT 35% versus 35%, and VF 14% versus 10%). More secondary prevention patients had appropriate therapies (26% versus 18%, P=0.02), but among these patients, the median number of episodes per patient was similar. Inappropriate therapies occurred in 15% of both groups and accounted for similar proportions of all detected and treated episodes (46% in primary prevention patients versus 34% in secondary prevention patients, P=0.09). Quality of life improved modestly in both groups, and mortality was similar. CONCLUSIONS: Primary prevention patients are slightly less likely to have appropriate therapies than secondary prevention patients, but episode density is similar among patients with appropriate therapies. SVT resulted in more than one third of therapies in both groups, but quality of life and mortality were similar.

Supraventricular Tachycardia Classification in the 12-Lead ECG Using Atrial Waves Detection and a Clinically Based Tree Scheme.

Specific supraventricular tachycardia (SVT) classification using surface ECG is considered a challenging task, since the atrial electrical activity (AEA) waves, which are a crucial element for obtaining diagnosis, are frequently hidden. In this paper, we present a fully automated SVT classification method that embeds our recently developed hidden AEA detector in a clinically based tree scheme. The process begins with initial noise removal and QRS detection. Then, ventricular features are extracted. According to these features, an initial AEA-wave search window is defined and a single AEA-wave is detected. Using a synthetic Gaussian signal and a linear combination of 12-lead ECG signals, all AEA-waves are detected. In accord with the atrial and ventricular information found, classification to atrial fibrillation, atrial flutter, atrioventricular nodal reentry tachycardia, atrioventricular reentry tachycardia, or sinus rhythm is performed in the framework of a clinically oriented decision tree. A study was performed to evaluate the classification from 68 patients (26 were used for the classifier's design, 42 were used for its validation). Average sensitivity of 83.21% [95% confidence interval (CI): 79.33-86.49%], average specificity of 95.80% (95% CI: 94.73-96.67%), and average accuracy of 93.29% (95% CI: 92.13-94.28%) were achieved compared to the definite diagnosis. In conclusion, the presented method may serve as a valuable decision support tool, allowing accurate detection of SVTs using noninvasive means.