Arrhythmias & electrophysiology
Clinical importance of tissue proximity indication during pulsed field ablation for atrial fibrillation: Insights from initial experience
Authors' conclusion
Acute PVI failure was significantly associated with poor tissue contact and higher voltage. However, acute PVI failure can be prevented with improved TPI-based contact information.
Study context
- Population
- Patients with paroxysmal atrial fibrillation (AF) undergoing pulsed field ablation (PFA) (at least 4 ablations per pulmonary vein (PV)) using the variable loop circular catheter (VLCC)
- Participants
- Twenty-one patients
- Comparison
- Failure sites vs Non-failure sites
- Failure sitesn = 8
- Outcome
- PVI failure after primary PFA
Main finding
As reported in the abstract
Patients with pulmonary vein isolation (PVI) failure
Four of 21 patients
8 failure sites
Further findings
TPI-positive site percentages · lower at failure sites
P < 0.001
Voltage · higher at failure sites
P = 0.003
| Outcome | P value |
|---|---|
| TPI-positive site percentages, first 7 vs last 14 casesIncreased significantly | P = 0.009 |
| PV gaps, first 7 vs last 14 casesDecreased | P = 0.332 |
- Tissue proximity indication (TPI)-positive site percentages, first 7 vs last 14 cases: First 7 cases 58 ± 29 %
- TPI-positive site percentages, first 7 vs last 14 cases: Last 14 cases 64 ± 26 %
- PV gaps, first 7 vs last 14 cases: First 7 cases 11%
- PV gaps, first 7 vs last 14 cases: Last 14 cases 4%
PV wall thickness
- No significant difference between failure sites and other sites
Left atrial bipolar voltage amplitude as determinant of PV gaps (ROC)
- Cut-off
- ≥2.24 mV
- Area under the curve
- 0.83
Original publication
Clinical importance of tissue proximity indication during pulsed field ablation for atrial fibrillation: Insights from initial experience. Heart Rhythm. Published 24 January 2025. doi:10.
Summarised from the published abstract; every number is checked against it