A modified electrocardiographic algorithm for differentiating typical atrioventricular node re-entrant tachycardia from atrioventricular reciprocating tachycardia mediated by concealed accessory pathway

Abstract

Non-invasive prediction of tachycardia mechanism is becoming clinically important in the era of catheter ablation for curing supraventricular tachycardia. Twelve-lead electrocardiograms (ECGs) during sinus rhythm and atrioventricular node re-entrant tachycardia (AVNRT) or atrioventricular reciprocating tachycardia (AVRT) with a narrow QRS complex were obtained from 154 consecutive adult patients who had received successful radiofrequency catheter ablation. The ECGs of initial 104 patients were analysed by three observers without knowledge of the electrophysiological diagnosis. The two arrhythmias were accurately diagnosed in 68% of cases. Three criteria were found to be discriminators of tachycardia mechanism by univariable analysis. Pseudo r/Q/S waves predicated AVNRT in 92% of cases (sensitivity 71%; specificity 95%). Retrograde P wave predicated AVRT in 86% of cases (sensitivity 75%; specificity 85%), RP interval > or =100 ms in 93% (sensitivity 71%; specificity 94%) and ST-segment elevation in lead aVR in 83% (sensitivity 71%; specficity 83%). According to the initial results, we proposed a modified stepwise ECG algorithm which used pseudo r/S/Q waves, RP interval and ST-segment elevation in lead aVR during tachycardia. Two observers assessed the modified algorithm in the remaining 50 patients. The algorithm was able to correctly diagnose the tachycardia mechanism in 84% and 87%, respectively. Using the modified algorithm can improve the accuracy and simplify the differential diagnosis between typical AVNRT and AVRT via concealed accessory pathway in adult patients.

Utility of 12‐Lead Electrocardiogram for Differentiating Paroxysmal Supraventricular Tachycardias in Dogs

“…Because antegrade conduction in both OAVRT and FAT is along the atrioventricular‐His‐Purkinje system, the QRS complex duration should remain within normal limits in the absence of functional or anatomical conduction abnormalities 24 . In humans, a tachyarrhythmia is classified as a narrow QRS complex tachycardia when the QRS duration is < 110 11,12,14,18 or 120 ms 9,10,13,15,16,19 . According to our study, in dogs a tachycardia could be considered narrow QRS complex tachycardia if the QRS duration is < 70 ms.…”

“…Depending on the study, location of the P wave relative to the QRS complex during tachycardia, P wave axis in the frontal and horizontal plane, PR and RP interval duration, presence of QRS alternation, or repolarization anomalies were good discriminators of tachycardia type 9–19 . Reported overall accuracy in differentiating SVT in humans by means of specific surface ECG criteria ranges between 75 and 97.8% 9–11,13–15,17–19 . P wave location, pseudo r′ wave in lead V1, QRS alternans and ST depression > 2 mm in lead II or elevation ≥ 1–1.5 mm in lead aVR during tachycardia, and presence of ventricular pre‐excitation during sinus rhythm are independent predictor of tachycardia mechanisms in human patients with symptomatic SVTs 9–11,13–15,18,19 …”

“…Twelve‐lead surface ECG is considered the 1st step in the diagnosis of SVT in humans, and several studies have validated its utility in differentiating narrow QRS complex tachycardia in patients that have undergone electrophysiologic examination for symptomatic tachyarrhythmias 9–19 . Depending on the study, location of the P wave relative to the QRS complex during tachycardia, P wave axis in the frontal and horizontal plane, PR and RP interval duration, presence of QRS alternation, or repolarization anomalies were good discriminators of tachycardia type 9–19 . Reported overall accuracy in differentiating SVT in humans by means of specific surface ECG criteria ranges between 75 and 97.8% 9–11,13–15,17–19 .…”

“…Reported overall accuracy in differentiating SVT in humans by means of specific surface ECG criteria ranges between 75 and 97.8% 9–11,13–15,17–19 . P wave location, pseudo r′ wave in lead V1, QRS alternans and ST depression > 2 mm in lead II or elevation ≥ 1–1.5 mm in lead aVR during tachycardia, and presence of ventricular pre‐excitation during sinus rhythm are independent predictor of tachycardia mechanisms in human patients with symptomatic SVTs 9–11,13–15,18,19 …”

Coronary sinus diameter by echocardiography to differentiate atrioventricular nodal reentrant tachycardia from atrioventricular reentrant tachycardia

“…History of neck pulsations has been proposed as a strong indicator of AVNRT [1], but in our experience this is highly subjective and unreliable. ECG recorded during tachycardia can give various clues, including presence of a pseudo r' wave in V 1 and pseudo s wave in inferior leads, ST depression [13][14][15][16][17], ST elevation in AVR [15,18] or QRS alternans [15,16,19,20]. However, these findings have a low sensitivity, are sometimes subjective and, most importantly, require ECG documentation during tachycardia, which may not be available.…”