Pressure monitoring predicts pulmonary vein occlusion in cryoballoon ablation.

PURPOSE: Pulmonary venography is routinely used to confirm pulmonary vein (PV) occlusion during cryoballoon ablation. However, this technique is significantly limited by the risks associated with contrast media, such as renal injury and contrast allergy. We hypothesized that PV occlusion can be predicted by elevation of the balloon catheter tip pressure, avoiding the need for contrast media.

METHODS: Forty-eight consecutive patients with paroxysmal atrial fibrillation who underwent PV isolation with the cryoballoon technique were enrolled. The balloon catheter tip pressure was measured in each PV before and after balloon inflation.

RESULTS: We analyzed 200 applications of cryoballoon ablation in 185 PVs (excluding 3 common PVs and 1 extremely small right inferior PV) of 48 patients (age, 70 ± 11 years; male, n = 28; mean left atrial diameter, 38 ± 6 mm). Compared with patients with unsuccessful occlusion, patients with successful occlusion demonstrated a larger change in pressure after balloon inflation (6 ± 8 vs. 2 ± 4 mmHg, P < 0.001), a lower minimum temperature (- 49 ± 6 vs. - 40 ± 8 °C, P < 0.001), and a higher PV isolation rate (97 vs. 64%, P < 0.001). The best cutoff value of a change in pressure for predicting PV occlusion was 4.5 mmHg, with a sensitivity of 67%, specificity of 83%, and predictive accuracy of 72%.

CONCLUSION: Pressure monitoring is helpful to confirm PV occlusion during cryoballoon ablation.