New catheter technique for recording left free-wall accessory atrioventricular pathway activation. Identification of pathway fiber orientation.

Abstract

The ability to record accessory atrioventricular (AV) pathway activation consistently may be uniquely beneficial in improving pathway localization, identifying anatomic relations, and providing insight into unusual conduction properties. For the purpose of recording left AV accessory pathway activation, an electrode catheter was specially designed for use in the coronary sinus. The orthogonal catheter has three sets of four electrodes spaced evenly around the circumference. Electrograms were recorded at low gain (<1 cm/mV) between adjacent electrodes on the same set (interelectrode distance, 1.5 mm, center to center). This provides a recording dipole perpendicular to the atrioventricular groove to enhance recording of accessory pathway activation while miinimizing overlapping atrial or ventricular potentials. The orthogonal electrode catheter was used in the electrophysiological study of 48 consecutive patients with 59 left AV accessory pathways. The catheter could be advanced along the coronary sinus beyond the site of earliest retrograde atrial activation in 49 of the 59 accessory pathways. Activation potentials were recorded from 45 of the 49 (92%) accessory pathways accessible to the catheter (5 of 5 anterior, 8 of 8 anterolateral, 15 of 16 lateral, 5 of 5 posterolateral, 5 of 5 posterior, and 7 of 10 posteroseptal). Accessory pathway potentials were validated by dissociating them from both atrial and ventricular activation by programmed-stimulation techniques. During surgery, accessory pathway potentials were identfied from orthogonal catheter electrodes in the coronary sinus in 14 of 16 accessory pathways (12 patients). Epicardial mapping confirmed the location of the accessory pathway, and direct pressure over the orthogonal catheter electrode that recorded the accessory pathway potential resulted in transient conduction block in nine of the 14 accessory pathways. Orthogonal electrode maps of the coronary sinus identified an oblique course in 39 of 45 recorded accessory pathways. Thirty-two of 38 left free-wall accessory pathways were oriented with atrial insertion 4-30 mm (median, 14 mm) proximal (posterior) to the ventricular insertion. In the remaining six free-wail accessory pathways, the lateral excursion could not be determined because either only the atrial end of the accessory pathway was recorded or activation of multiple pathway fibers prevented tracking of individual strands. The seven recorded posteroseptal pathways exhibited accessory pathway potentials throughout an 8-18-mm (median, 10 mm) length of the proximal coronary sinus, but fiber orientation was difficult to determine. We conclude that left AV accessory pathway activation can be recorded consistently from orthogonal catheter electrodes in the coronary sinus. Direct accessory pathway recordings revealed an oblique fiber orientation and may provide more precise loalization for surgical or catheter ablation. (Circulation 1988;78:598-610) E a lectrophysiological studies in patients with of accessory atrioventricular (AV) pathways b...

Coronary Sinus-Ventricular Accessory Connections Producing Posteroseptal and Left Posterior Accessory Pathways

“…Ventricular activation recorded from the MCV, PCV, or CS diverticulum preceded endocardial ventricular activation (Figure 2). A highfrequency potential similar to an antegrade accessory pathway activation potential, 15 presumably generated by an extension of the CS myocardial coat (Figures 1 and 3) was recorded from the MCV, PCV, or neck of a CS diverticulum before the earliest far-field ventricular potential, and the antegrade CSE potential was dissociated from local atrial and ventricular activation by the use of ventricular extrastimuli ( Figure 4). 15 …”

“…The earliest high-frequency potential (similar to a retrograde AP potential) 15 was recorded from the MCV, PCV, or neck of a CS diverticulum, and was presumably generated by an extension of the CS myocardial coat (CSE in Figure 5). The CSE potential was followed by activation of the CS myocardial coat, with the earliest CS myocardial coat potential recorded near the orifice of the vein ( Figure 5A, first complex, CS 1 in electrograms MCV-Bip 3-4 and CS 9 ).…”

Sites of conduction block in accessory atrioventricular pathways. Basis for concealed accessory pathways.

“…24 The catheter was inserted percutaneously into the left subclavian vein, right internal jugular vein, or the left antecubital vein and was advanced into the coronary sinus and positioned as far anteriorly as possible in the great cardiac vein. Close bipolar electrograms with the recording dipole oriented perpendicular to the axis of the catheter were obtained by recording between adjacent electrodes within a circumferential group of electrodes.…”

“…Of the 33 left free-wall (24) and posteroseptal (9) accessory pathways that never exhibited antegrade conduction, the site of permanent antegrade block was at or near the ventricular interface in 29 ( Figure 6). Pacing the accessory pathway directly in one patient still failed to produce ventricular preexcitation ( Figure 7).…”

A Unipolar Coronary Sinus Mapping Study of Patients with Left-Sided Atrioventricular Accessory Pathways

“…For all subjects, the CS electrode catheter could be inserted into the peripheral anterior region of the CS lumen. According to the EPS conducted by Jackman, et al, 13) the CS lumen in the left anterior oblique (60°) view was divided into six equal segments alphabetically, termed A to F, from the distal CS terminal as shown in Figure 1A. All atrial components of the unipolar CS electrogram showed the fundamental biphasic configuration composed of initial positive and secondary negative parts.…”