Supraventricular tachycardia with alternating eccentric atrial activation: What is the mechanism?

An irregularly irregular supraventricular tachycardia: What is the mechanism?

“…The cycle length alternation has been also reported in orthodromic AVRT with antegrade conduction alternating between fast and slow pathways 3 . In addition, orthodromic AVRT with alternating both cycle length and atrial activation sequence has been reported because of alternating retrograde conduction between two concealed left‐sided APs 4 . However, in our case, atrial activation sequences were identical regardless of VA intervals.…”

“…3 In addition, orthodromic AVRT with alternating both cycle length and atrial activation sequence has been reported because of alternating retrograde conduction between two concealed left-sided APs. 4 However, in our case, atrial activation sequences were identical regardless of VA intervals. Another paper reported that cycle length alternation during orthodromic AVRT was caused by conduction delay at the left atrium-CS musculature connection, 5…”

Ventricular overdrive pacing during supraventricular tachycardia with alternating cycle length: What is the diagnosis?

“…The differential diagnoses for SVT2 include atrial tachycardia (AT), orthodromic AV reciprocating tachycardia (AVRT) using two distinct retrograde accessory pathways, 1,2 and atypical AVNRT with two retrograde AVN pathways 3…”

“…SVT with CL alternation has been reported 1–3,7 . However, the response of VOP during SVT with CL alternations has rarely been described in the literature.…”

“…SVT with CL alternation has been reported. [1][2][3]7 However, the response of VOP during SVT with CL alternations has rarely been described in the literature. This case describes AVNRT with CL alternation and the interpretation of the response of the VOP during it.…”