Pulmonary vein isolation with “ablation index” via single trans-septal
crossing: Critical role of carina isolation.
Background. Pulmonary veins (PV) reconnection is the most common reason
for atrial fibrillation (AF) recurrence. The ablation-index is a marker
of ablation lesion quality which use achieves high percentages of first
pass isolation and improved results of AF ablation. Most operators use a
double trans-septal approach with confirmation of PV isolation with a
circular mapping catheter. In the present study we aimed to show that an
ablation-index guided procedure using a single trans-septal approach and
ablation catheter only would achieve adequate PV isolation while
demonstrating the critical role of the carina in PV isolation. Methods.
76 consecutive patients with paroxysmal AF: 34 patients underwent WACA,
32 patients underwent WACA+ (including empiric carina isolation) and 10
patients underwent a staged procedure of WACA followed by WACA+ in case
of lack of first pass isolation. All procedures were performed via
single trans-septal. Results. Compared to WACA-only, WACA+ increased the
odds of PV isolation from 65% to 91%, p=0.012. In WACA-only, ablation
of the carina was needed to achieve PV isolation. The role of the carina
was confirmed in 10 patients with sequential ablation. PV isolation was
confirmed by inserting a circular mapping catheter through the single
trans-septal sheath. At 18 months of follow-up [IQR 15.2-20.8
months], freedom from AF was 84% for the entire cohort. Conclusion.
Our study confirms the high success rate of PV isolation using ablation
index and shows that this can be achieved via single trans-septal
crossing. Our study confirms the role of the carina in PV isolation.