[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.

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.

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.

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.

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.

Flecainide versus digoxin for fetal supraventricular tachycardia: Comparison of two drug treatment protocols.

BACKGROUND: The optimal treatment for fetal supraventricular tachycardia (SVT) with 1:1 atrioventricular relationship is unclear. OBJECTIVE: We compared the effectiveness of transplacental treatment protocols used in 2 centers. METHODS: Pharmacologic treatment was used in 84 fetuses. Maternal oral flecainide was the primary therapy in center 1 (n = 34) and intravenous maternal digoxin in center 2 (n = 50). SVT mechanism was classified by mechanical ventriculoatrial (VA) time intervals as short VA or long VA. Treatment success was defined as conversion to sinus rhythm (SR), or rate control, defined as >15% rate reduction. RESULTS: Short VA interval occurred in 67 fetuses (80%) and long VA in 17 (20%). Hydrops was present 28 of 84 (33%). For short VA SVT, conversion to SR was 29 of 42 (69%) for digoxin and 24 of 25 (96%) for flecainide (P = .01). For long VA SVT, conversion to SR and rate control was 4 of 8 (50%) and 0 of 8, respectively, for digoxin, and 6 of 9 (67%) and 2 of 9 (cumulative 89%) for flecainide (P = .13). In nonhydropic fetuses, digoxin was successful in 23 of 29 (79%) and flecainide in 26 of 27 (96%) (P = .10). In hydrops, digoxin was successful in 8 of 21 (38%), flecainide alone in 6 of 7 (86%, P = .07 vs digoxin), and flecainide ± amiodarone in 7 of 7 (100%) (P = .01). Intrauterine or neonatal death occurred in 9 of 21 hydropic fetuses treated with digoxin (43%), compared to 0 of 7 (P = .06) treated with flecainide. CONCLUSIONS: Flecainide was more effective than digoxin, especially when hydrops was present. No adverse fetal outcomes were attributed to flecainide.

Prediction of atrial fibrillation in patients with supraventricular tachyarrhythmias treated with catheter ablation or not. Classical scores are not useful.

BACKGROUND: Atrial fibrillation (AF) and other supraventricular tachyarrhythmias (SVTA) [atrial flutter (AFL), atrioventricular nodal reentrant tachycardia (AVNRT), atrioventricular reentrant tachycardia (AVRT) and preexcitation syndrome (PS)] are frequently associated. We assessed the AF occurrence frequency and predictors according to the nature of SVTA and completion of SVTA ablation. METHODS AND RESULTS: 4169 patients were referred for SVTA (typical AVNRT: 1338, AVRT over a concealed accessory pathway: 329, atypical AVNRT: 205, AFL: 1321; PS: 976); mean age was 50±20years; electrophysiological study (EPS) was systematic; patients were followed for a mean duration of 3±4.5years. Ablation of SVTA was performed in 2949 patients (71%) and 1220 patients were not treated or treated with antiarrhythmic drugs. AF developed in 469 patients (11.2%). In the multivariable model, AF prior to ablation, history of AF, nature of SVTA (AFL), and presence of heart disease were associated with a high risk of AF during follow-up. Presence of heart failure, old age, diabetes and vascular disease were not predictive of AF. Ablation was a weak but significant factor of AF prevention. A score based on nature of SVTA, presence of heart disease and history of AF is proposed. CONCLUSIONS: AF occurrence in patients with SVTA cannot be predicted by the presence of heart failure, old age, diabetes and vascular disease, but only by the following criteria, presence of heart disease, history of AF and nature of the SVTA (SVTA).

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.

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.

Supraventricular tachycardias: proposal of a diagnostic algorithm for the narrow complex tachycardias.

The narrow complex tachycardias (NCTs) are defined by the presence in a 12-lead electrocardiogram (ECG) of a QRS complex duration less than 120ms and a heart rate greater than 100 beats per minute; those are typically of supraventricular origin, although rarely narrow complex ventricular tachycardias have been reported in the literature. As some studies document, to diagnose correctly the NCTs is an arduous exercise because sometimes those have similar presentation on the ECG. In this paper, we have reviewed the physiopathological, clinical, and ECG findings of all known supraventricular tachycardias and, in order to reduce the possible diagnostic errors on the ECG, we have proposed a quick and accurate diagnostic algorithm for the differential diagnosis of NCTs.