Direct Pressure Monitoring Accurately Predicts Pulmonary Vein Occlusion During Cryoballoon Ablation

Abstract

Cryoballoon ablation (CBA) is an established therapy for atrial fibrillation (AF). Pulmonary vein (PV) occlusion is essential for achieving antral contact and PV isolation and is typically assessed by contrast injection. We present a novel method of direct pressure monitoring for assessment of PV occlusion.Transcatheter pressure is monitored during balloon advancement to the PV antrum. Pressure is recorded via a single pressure transducer connected to the inner lumen of the cryoballoon. Pressure curve characteristics are used to assess occlusion in conjunction with fluoroscopic or intracardiac echocardiography (ICE) guidance. PV occlusion is confirmed when loss of typical left atrial (LA) pressure waveform is observed with recordings of PA pressure characteristics (no A wave and rapid V wave upstroke). Complete pulmonary vein occlusion as assessed with this technique has been confirmed with concurrent contrast utilization during the initial testing of the technique and has been shown to be highly accurate and readily reproducible.We evaluated the efficacy of this novel technique in 35 patients. A total of 128 veins were assessed for occlusion with the cryoballoon utilizing the pressure monitoring technique; occlusive pressure was demonstrated in 113 veins with resultant successful pulmonary vein isolation in 111 veins (98.2%). Occlusion was confirmed with subsequent contrast injection during the initial ten procedures, after which contrast utilization was rapidly reduced or eliminated given the highly accurate identification of occlusive pressure waveform with limited initial training.Verification of PV occlusive pressure during CBA is a novel approach to assessing effective PV occlusion and it accurately predicts electrical isolation. Utilization of this method results in significant decrease in fluoroscopy time and volume of contrast.

Cryoballoon Pressure Waveform Change during Balloon Inflation is not a Reliable Predictor of Adequate Pulmonary Vein Occlusion

“…In prior research, the accuracy of pressure monitoring in detecting PV occlusion was confirmed in 46 of 47 veins by TEE‐CFD, but we only confirmed complete occlusion in 43 of 67 veins (64%). Kosmidou et al supported the accuracy of pressure monitoring, because their success rate was equivalent to those found in other studies; however, our study showed that PV pressure monitoring had only a 64.1% positive predictive value, so we could not reach the same conclusion.…”

“…In our study, we examined the accuracy of monitoring pressure changes recorded from the distal tip of inflated balloon in predicting PV occlusion (with angiography as the standard for comparison). We recorded pressure changes from LA to PA in 67 of 72 veins (93%), which is comparable to what other published studies have found . In contrast to Siklódy et al., we could not confirm the accuracy of pressure monitoring in assessing complete PV occlusion during cryoballoon ablation.…”

“…Recent studies have suggested that changes in the pressure waveform recordings at the cryoballoon tip during occlusion are predictive of successful PV occlusion. In this study, we sought to confirm these findings in a series of patients who underwent cryoablation for paroxysmal AF …”

Pressure‐guided second‐generation cryoballoon pulmonary vein isolation: Prospective comparison of the procedural and clinical outcomes with the conventional strategy

“…With this background, Siklódy et al initially reported that the PV occlusion well correlated with the changes in the pressure curve recorded from the distal tip of the CB catheter and that this technique could be applied to the first‐generation CB‐PVI procedure. Other pilot and small observational studies showed that additional pressure curve monitoring significantly reduced the contrast volume utilization (23 and 8 mL) as compared to the conventional strategy in the first‐generation CB‐PVI . The present study had three major differences from the prior studies .…”

Dye or not dye, the cryoablation dilemma

“…In this issue of the journal, Hasegawa et al report the results of a prospective randomized study with a comparison of the pressure‐wave approach as an alternative modality to assess pulmonary vein (PV) occlusion and the conventional strategy of contrast injection to guide cryoballoon PV isolation. The authors need to be applauded for having shown the value of this alternative technique, only described elsewhere in a anecdotal fashion or small clinical studies …”