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Atrioventricular Reentrant Tachycardia with Intraatrial Conduction Block SHINSUKE MIYAZAKI, M.D.,∗ ,† TSUNEMICHI KINJO, M.D.,∗ ,† and YOSHITO IESAKA, M.D.∗ ,† From the ∗ Tsuchiura Kyodo Hospital, Ibaraki, Japan; and †Hokushin General Hospital, Nagano, Japan
A 72-year-old man with regular narrow QRS tachycardia was admitted to Hokushin General Hospital for catheter ablation. He had no structural heart disease. Venous access was obtained under local anesthesia from the right femoral and jugular veins to introduce 4 catheters. Three quadripolar catheters were positioned at the right atrium (RA), His bundle region, and right ventricle. A decapolar catheter was introduced from the right jugular vein and positioned within the coronary sinus. Clinical narrow QRS tachycardia was easily inducible by programmed stimulation, and it was diagnosed as atrioventricular reentrant tachycardia (AVRT) via concealed posterolateral accessory pathway at mitral annulus. Figure 1 shows the induced tachycardia with a cycle length of 325 milliseconds. The tachycardia was success-
fully eliminated by radiofrequency application targeting the accessory pathway. AVRT is a macroreentrant tachycardia involving both atrium and ventricle. In this case, mapping catheters were placed at standard position of electrophysiological test, whereas 2:1 activity was observed at high RA during AVRT. Apparently it looked like AV dissociation; however, this was the intraatrial conduction block between the atrial insertion of posterolateral accessory pathway and high RA. In fact, extrastimulus from high RA showed significant intraatrial conduction delay. Although atrial pacing is usually performed from high RA in electrophysiological laboratory, coronary sinus should be considered as alternative pacing site in such cases.
Figure 1. Atrioventricular reentrant tachycardia was induced by programmed stimulation. HRA = high right atrium; His = His bundle region; CS = coronary sinus; RVA = right ventricular apex; d = distal; p = proximal; H = His bundle potential.
J Cardiovasc Electrophysiol, Vol. 25, p. 1407, December 2014. No disclosures. Address for correspondence: Shinsuke Miyazaki, M.D., Cardiology Division, Cardiovascular Center, Tsuchiura Kyodo Hospital, 11–7 Manabeshinmachi, Tsuchiura, Ibaraki 300–0053, Japan. Fax: +81 29 826 2411; E-mail: [email protected] doi: 10.1111/jce.12531
EP Image
Atrioventricular Reentrant Tachycardia with Intraatrial Conduction Block SHINSUKE MIYAZAKI, M.D.,∗ ,† TSUNEMICHI KINJO, M.D.,∗ ,† and YOSHITO IESAKA, M.D.∗ ,† From the ∗ Tsuchiura Kyodo Hospital, Ibaraki, Japan; and †Hokushin General Hospital, Nagano, Japan
A 72-year-old man with regular narrow QRS tachycardia was admitted to Hokushin General Hospital for catheter ablation. He had no structural heart disease. Venous access was obtained under local anesthesia from the right femoral and jugular veins to introduce 4 catheters. Three quadripolar catheters were positioned at the right atrium (RA), His bundle region, and right ventricle. A decapolar catheter was introduced from the right jugular vein and positioned within the coronary sinus. Clinical narrow QRS tachycardia was easily inducible by programmed stimulation, and it was diagnosed as atrioventricular reentrant tachycardia (AVRT) via concealed posterolateral accessory pathway at mitral annulus. Figure 1 shows the induced tachycardia with a cycle length of 325 milliseconds. The tachycardia was success-
fully eliminated by radiofrequency application targeting the accessory pathway. AVRT is a macroreentrant tachycardia involving both atrium and ventricle. In this case, mapping catheters were placed at standard position of electrophysiological test, whereas 2:1 activity was observed at high RA during AVRT. Apparently it looked like AV dissociation; however, this was the intraatrial conduction block between the atrial insertion of posterolateral accessory pathway and high RA. In fact, extrastimulus from high RA showed significant intraatrial conduction delay. Although atrial pacing is usually performed from high RA in electrophysiological laboratory, coronary sinus should be considered as alternative pacing site in such cases.
Figure 1. Atrioventricular reentrant tachycardia was induced by programmed stimulation. HRA = high right atrium; His = His bundle region; CS = coronary sinus; RVA = right ventricular apex; d = distal; p = proximal; H = His bundle potential.
J Cardiovasc Electrophysiol, Vol. 25, p. 1407, December 2014. No disclosures. Address for correspondence: Shinsuke Miyazaki, M.D., Cardiology Division, Cardiovascular Center, Tsuchiura Kyodo Hospital, 11–7 Manabeshinmachi, Tsuchiura, Ibaraki 300–0053, Japan. Fax: +81 29 826 2411; E-mail: [email protected] doi: 10.1111/jce.12531
