Electroanatomic mapping of transseptal conduction during coronary sinus pacing in patients with paroxysmal atrial fibrillation

Abstract

During distal CS pacing, a preferential site of transseptal conduction near the CS ostium was demonstrated in patients with paroxysmal AF. This has clinical implications when surgical dissection or catheter ablation is considered to eliminate interatrial connection in patients with AF.

Deterioration of interatrial conduction in patients with paroxysmal atrial fibrillation: Electroanatomic mapping of the right atrium and coronary sinus

“…In the present study, the activation velocities of cross-CSo and intra-CS during distal CS pacing were measured. These measurements should represent the actual conduction velocities since the preferential conduction route during distal CS pacing is along the long axis of the CS as observed previously (9,17) (Fig 3). We found that the activation velocities of intra-CS were similar in the two groups, whereas the cross-CSo activation velocities in the AF group appeared slower than those in the control group.…”

“…Using the CARTO mapping system, different activation patterns of the right atrium during pacing from the distal CS have been observed, with most right atria presenting a single transseptal breakthrough near the CS ostium (9,17). In addition, using the Ensite 3000 noncontact mapping system, O'Donnell et al observed similar preferential inter-atrial conduction route during pacing in the left upper pulmonary vein (3).…”

“…Nevertheless, the exact deteriorated conduction areas are still not clear. Fiber connections between the two atria around the CS ostium have been highlighted to play an important role for interatrial conduction(3,9,17).Activation velocity as a parameter of interatrial conductionMost of the previous studies have evaluated the inter-and intra-atrial conduction properties using conduction times between remote sites. The accuracy of these evaluations therefore must have been influenced by the inter-individual variance of measurement sites.…”

Catheter ablation of left atrial focal tachycardia guided by electroanatomic mapping and new insights into interatrial electrical conduction

“…5,15,19 Therefore, conceivably the CS may play a major role in the interatrial electrical connection during ATs originating from the lateral LA and left PVs that are close to the distal CS. In the present study, RA breakthrough sites at the CS ostium was found in one MA tachycardia and one tachycardia from inferoposterior LA but in none of the three left PV tachycardias having biatrial electroanatomic maps.…”