To determine the value of alternation of QRS morphology in determining the site of origin of sustained narrow QRS supraventricular tachycardia (SVT), we retrospectively studied 163 distinct tachycardias in 161 patients (ages 4 to 91 years) in whom the site of origin of SVT was proven by intracardiac electrophysiologic study. Sustained SVT was defined as lasting longer than 30 sec. Narrow QRS was defined as QRS width less than 0.12 sec. Atrial fibrillation and flutter were excluded. The presence or absence of QRS alternation was judged at least 10 sec after initiation of SVT. Circus movement tachycardia with anterograde AV node conduction and a retrograde accessory AV pathway was seen in 89 patients (58 with Wolff-Parkinson-White syndrome, 31 with concealed accessory pathway); intra-AV nodal reentrant tachycardia (AVNT) was present in 57 cases, and 17 tachycardias were atrial in origin. QRS alternation was present in 36 of 163 cases (22%). In only eight of these 36 did RR interval length alternation accompany alternation in QRS morphology. Thirty-three of 36 (92%) tachycardias with QRS alternation were circus movement tachycardias. Two were atrial in origin and one was AVNT. We conclude that the presence of QRS alternation during sustained narrow QRS SVT is highly indicative of a retrograde accessory AV pathway in the tachycardia circuit.

Value of QRS alteration in determining the site of origin of narrow QRS supraventricular tachycardia.

One hundred eighty-seven patients with clinically documented supraventricular tachycardia with a narrow QRS complex were admitted for electrophysiologic study. The diagnoses after this study were circus movement tachycardia using an accessory pathway in 50 patients, atrioventricular nodal tachycardia in 50 patients, atrial flutter in 50 patients, atrial tachycardia in 27 patients and an incessant tachycardia retrogradely using a slowly conducting accessory pathway in 10 patients. On retrospective analysis, 5 criteria on the 12-lead electrocardiogram during tachycardia were analyzed for their value in making the diagnosis of site of origin. These criteria were P-wave location, axis of the P wave, atrial rate, alternation of the QRS complex and atrioventricular relation. Fifty-seven patients with a narrow QRS tachycardia were prospectively studied using the 5 criteria. A correct diagnosis was made in 48 of the 57 patients (84%). Thus, in most patients with a narrow QRS tachycardia, information from the 12-lead electrocardiogram is adequate for diagnosis.

Differential diagnosis of tachycardia with narrow QRS complex (shorter than 0.12 second)

The effect of operation and the effect of the imposition of an occluding device on atrial function for patients with an atrial septal defect (ASD) has never been studied. Thus, the aim of this study was to evaluate for the first time both left atrial (LA) and right atrial (RA) function of children after transcatheter ASD closure with that of sex- and age-matched patients with surgically treated ASD, and sex- and age-matched control subjects using strain (ϵ) and ϵ rate imaging (SR). In all, 45 participants formed our studied sample: 15 patients after successful ASD device closure (ASD-D [atrial septal defect device closure] group, mean age: 9 ± 3 years) and 15 age- and sex-matched patients after successful ASD surgical closure (ASD-S [atrial septal defect surgical closure] group, mean age: 9 ± 3 years). All patients underwent ASD correction at least 6 months before the study. As a control group we selected 15 age- and sex-matched control subjects. In the ASD-S group the peak systolic ϵ and SR values were significantly reduced in both RA and LA when compared with control and ASD-D groups ( P

Atrial Function After Surgical and Percutaneous Closure of Atrial Septal Defect: A Strain Rate Imaging Study

A New Electrocardiographic Algorithm Using Retrograde P Waves for Differentiating Atrioventricular Node Reentrant Tachycardia From Atrioventricular Reciprocating Tachycardia Mediated by Concealed Accessory Pathway

The localization of bypass tracts in the Wolff-Parkinson-White syndrome from the surface electrocardiogram.

Electrophysiological study of 26 patients with paroxysmal supraventricular tachycardia showed that the tachycardias were due to a circus movement using a lateral atrioventricular bypass tract as a retrograde limb of the circuit. The Wolff-Parkinson-White syndrome was overt in 19 cases and concealed in the remaining seven.

Retrograde P wave polarity and morphology during tachycardia were studied and related to the location of the bypass tract on the left or right side of the heart. In all cases the P wave during tachycardia was located after the QRS complex. Of 19 cases with left bypass tract, the retrograde P wave in lead I was negative in 14, diphasic (−.+) in four, and indeterminate in one case. In lead V, the P wave was positive in 16 cases and indeterminate in three. Of seven cases with right bypass tract, the retrograde P wave in lead I was positive and bimodal in six cases and indeterminate in the remaining case, while it was negative and bimodal in lead V1 in all but one case.

Hence, it may be concluded that analysis of retrograde P wave morphology during tachycardia, together with other electrocardiographs factors, can be useful in determining the type of circuit used in reciprocating tachycardia.

R. Garcia Civera

Papers

Retrograde P wave polarity in reciprocating tachycardia utilizing lateral bypass tracts