ABSTRACT
INTRODUCTION: Usefulness of the interval between the last pacing stimulus and the last entrained atrial electrogram (SA) minus the tachycardia ventriculoatrial (VA) interval in the differential diagnosis of supraventricular tachycardias with long (>100 ms) VA intervals has not been prospectively studied in a large series of patients. Our objective was to assess the usefulness of the difference SA-VA in diagnosing the mechanism of those tachycardias in patients without preexcitation. The results were compared with those obtained using the corrected return cycle (postpacing interval-tachycardia cycle length-atrioventricular [AV] nodal delay). METHODS AND RESULTS: We included 314 consecutive patients with inducible sustained supraventricular tachycardias with VA intervals >100 ms undergoing an electrophysiologic study. Atrial tachycardias were excluded. Tachycardia entrainment was attempted through pacing trains from right ventricular apex. The SA-VA difference and the corrected return cycle were calculated for every patient. Electrophysiologic study revealed 82 atypical AV nodal reentrant tachycardias (AVNRT) and 237 AV reentrant tachycardias (AVRT) using septal (n = 91) or free-wall (n = 146) accessory pathways (APs). A SA-VA difference >110 ms identified an atypical AVNRT with sensitivity, specificity, positive and negative predictive values of 99%, 98%, 95%, and 99.5%, respectively. Similarly, these values were 88%, 83%, 77%, and 92% for SA-VA difference <50 ms in identifying AVRT through a septal versus free-wall AP. The SA-VA difference showed higher accuracy in septal AP identification than that obtained using the corrected return cycle. CONCLUSION: The difference SA-VA provides a simpler electrophysiologic maneuver that reliably differentiates atypical AVNRT from AVRT regardless of concealed AP location.
Subject(s)
Atrioventricular Node/physiology , Heart Conduction System/physiology , Tachycardia, Paroxysmal/diagnosis , Tachycardia, Paroxysmal/physiopathology , Tachycardia, Supraventricular/diagnosis , Tachycardia, Supraventricular/physiopathology , Adolescent , Adult , Aged , Aged, 80 and over , Cardiac Pacing, Artificial/methods , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Prospective Studies , Tachycardia, Paroxysmal/therapy , Tachycardia, Supraventricular/therapy , Time Factors , Young AdultABSTRACT
This review is aimed at discussing the diagnostic value of the different electrocardiographic criteria so far described in the differential diagnosis of the major forms of paroxysmal supraventricular tachycardias (PSVTs). The predictive value of different combinations of these independent electrocardiographic (ECG) signs in distinguishing atrioventricular reentrant tachycardias (AVRTs) through a concealed accessory pathway (AP) versus atrioventricular nodal reentrant tachycardias (AVNRTs) are discussed in detail. In addition, the adjunctive diagnostic value of simple, bedside clinical variables and their combinations to the ECG interpretation in differentiating both tachycardia mechanisms is also reviewed.
Subject(s)
Electrocardiography , Tachycardia, Atrioventricular Nodal Reentry/diagnosis , Tachycardia, Supraventricular/diagnosis , Diagnosis, Differential , Heart Conduction System/physiopathology , Humans , Logistic Models , Tachycardia, Atrioventricular Nodal Reentry/physiopathology , Tachycardia, Supraventricular/physiopathologyABSTRACT
OBJECTIVES: The aim of this study was to assess the independent predictive contribution to the electrocardiogram (ECG) of bedside clinical variables to distinguish the major forms of paroxysmal supraventricular tachycardias. BACKGROUND: Atrioventricular nodal re-entrant tachycardias (AVNRTs) and orthodromic reciprocating tachycardias (ORTs), through concealed accessory pathways, are major mechanisms of paroxysmal atrioventricular re-entrant tachycardias. METHODS: We prospectively included 370 consecutive patients undergoing an electrophysiologic study for paroxysmal, regular, narrow-QRS complex tachycardias without pre-excitation in sinus rhythm. A diagnostic interpretation of ECG recordings was performed by 2 observers blinded to invasive diagnosis used as gold standard. The independent diagnostic contribution of basic clinical variables from a 7-item questionnaire was analyzed alone and in combination with the ECG interpretation by stepwise logistic regression. RESULTS: AVNRTs and ORTs were demonstrated in 262 and 108 patients, respectively. Age at symptom onset (odds ratio [OR]: 1.27), presence of palpitations in the neck (OR: 3.54), and female sex (OR: 2.96) (all p = 0.0001) were the clinical variables with significant diagnostic power for AVNRT diagnosis. These variables were selected by the logistic model as predictors of the tachycardia diagnosis when the ECG interpretation was included in the analysis (C statistic = 0.81 vs. 0.75 with clinical variables alone; p = 0.003). Neck palpitation was the only predictor of AVNRT when positive ECG findings were lacking. CONCLUSIONS: Age at the onset of symptoms, sensation of rapid regular pounding in the neck during tachycardia, and female sex are the only significant clinical variables in the differential diagnosis of paroxysmal atrioventricular reciprocating tachycardias in patients without pre-excitation in sinus rhythm. Their consideration adds significant diagnostic information to the ECG.
