QDOT MICROTM Catheter for Cavotricuspid isthmus ablation

Beside the fact that QDOT MICROTM Catheter QMODE+ based ablation for PVI has been evaluated in several trials and studies there is only limited data for catheter ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL), (Figure 3 ). The main concern about vHPSD is the lack of transmurality in regions with thicker tissue like the CTI. However, data utilizing 50W in studies by Kwon et al. and Yavin et al. reported a success rate for CTI block of 100%.
Schillaci et al. evaluated vHPSD ablation of the CTI in 28 consecutive patients (FAST) and compared the data to the last 30 consecutive patients who, previously, underwent CTI ablation by STSF guided by AI (control). For both groups an ILD of ≤ 6 mm was aimed. The vHPSD ablation was as effective as AI-guided ablation in achieving acute CTI block (first pass rate: 89% vs 93%, p  = 0.59), with a shorter RF time (88 ± 40 seconds vs 492 ± 269 seconds,p  < 0.001) and similar procedure (30 ± 4 min vs 34 ± 10 min, p  = 0.5) time was observed.
Besides PVI in the FAST and FURIOUS PVI study CTI block was achieved by Qmode+ only in 13 / 13 patients. In one patient with a repeat procedure the CTI was checked and was found to be durable blocked. Similar findings have been evaluated in the FAST and FURIOUS CTI study. Here complete CTI block using vHPSD ablation was achieved in all 15 patients. A median of 23 (20, 39) RF applications over a median RF ablation time of 92 (78, 154) seconds were applied and no periprocedural complications, no charring and no steam pops were observed.
The preliminary data show that vHPSD ablation might represent an effective and safe strategy to achieve bidirectional CTI block for the treatment of typical AFL.