A single atrial stimulation resetting his bundle during tachycardia: a new diagnostic methods of atrial tachycardia distinguishing from other tachycardias

Comparison of atrial-His intervals during tachycardia and atrial pacing in patients with long RP tachycardia.

INTRODUCTION The purpose of this study is to describe a simple and reliable diagnostic maneuver that allows for the rapid differentiation of atypical AV nodal reentrant tachycardia (AVNRT) from other causes of long RP tachycardia. Long RP tachycardias may be caused by atypical AVNRT, orthodromic reciprocating tachycardia (ORT) involving a slowly conducting retrograde accessory pathway, or atria...

His bundle tachycardia

His bundle electrocardiography during bidirectional tachycardia.

His bundle electrocardiography in a patient with a digitalis-induced bidirectional tachycardia revealed absence of His spike preceding earliest onset of ventricular activation during the bidirectional tachycardia. However, His potential preceded ventricular activation of normal complexes at a constant H-V interval of 35 msec. The presence of fusion QRS complexes, capture QRS complexes, the anal...

His bundle electrogram during bidirectional tachycardia.

The case is reported of a 66-year-old woman with bidirectional tachycardia caused by digitalis intoxication. His bundle records demonstrated the presence of two foci, one junctional and the other a fascicular one.

A Particular Bigeminy During Atrial Tachycardia

The ECG shows clearly visible P waves only in lead V1 (Fig. 1). Regular PP intervals and an isoelectric baseline are present between the P waves, so the diagnosis is atrial tachycardia [1]. During the ECG recording, lead V1 shows 12 P waves but some of these are not visible because they are concealed by the QRS complex (Fig. 2). In lead V1, the beats following the long RR intervals are conducte...