Variation in the frozen lesion size according to the non-occluded application duration and technique for cryoballoon ablation.

OBJECTIVE: The frozen lesion formation created by cryoballoon ablation, especially with non-occluded applications, has not been fully evaluated. This study aimed to validate the lesion size under different cryoballoon ablation settings: application duration, push-up technique, and laminar flow. METHODS: The frozen lesion size was evaluated immediately after ending the freezing with three different application durations (120, 150, and 180 seconds) in porcine hearts (N = 24). During the application, the push-up technique was applied at 10, 20, and 30 seconds after starting the freezing with or without laminar flow. RESULTS: The lesion size was significantly correlated with the nadir balloon temperature (P<0.001). The lesion volume became significantly larger after 150 seconds than 120 seconds (1272mm3 versus 1709mm3, P = 0.004), but not after 150 seconds (versus 1876mm3 at 180 seconds, P = 0.29) with a comparable nadir balloon temperature. Furthermore, the lesion volume became significantly larger with the push-up technique with the largest lesion size with a 20-second push-up after the freezing (1193mm3 without the push-up technique versus 1585mm3 with a push-up at 10 seconds versus 1808mm3 with a push-up at 20 seconds versus 1714mm3 with a push-up at 30 seconds, P = 0.04). Further, the absence of laminar flow was not associated with larger lesion size despite a significantly lower nadir balloon temperature. CONCLUSION: The frozen lesion size created by cryoballoon ablation became larger with longer applications at least 150 seconds and with a push-up technique especially at 20 seconds after the freezing.

Influence of low body weight on long-term clinical outcomes in patients with venous thromboembolism: From the COMMAND VTE registry.

INTRODUCTION: There is a paucity of data on the influence of low body weight on clinical outcomes in patients with acute venous thromboembolism (VTE). MATERIALS AND METHODS: The COMMAND VTE registry is a multicenter cohort study enrolling 3027 consecutive patients with acute symptomatic VTE. The current study population consisted of 2778 patients with available body weight value, who were divided into 2 groups; 1705 patients with lower body weight (≤60 kg) and 1073 patients with higher body weight (>60 kg). RESULTS: Patients with lower body weight were older (70.8 versus 60.9 years, P < 0.001), and more often women (75% versus 38%, P < 0.001), and more often had active cancer (27% versus 19%, P < 0.001) than those with higher body weight. The cumulative 5-year incidence of recurrent VTE was not significantly different between the 2 groups (10.6% versus 10.7%, P = 0.51). The cumulative 5-year incidences of major bleeding and all-cause death were significantly higher in patients with lower body weight than in those with higher body weight (14.6% versus 9.6%, P < 0.001, and 35.8% versus 19.8%, P < 0.001, respectively). The excess adjusted risk of patients with lower body weight relative to those with higher body weight remained significant for major bleeding and all-cause death (HR 1.57, 95%CI: 1.16-2.12, P = 0.003, and HR 1.50, 95%CI: 1.24-1.81, P < 0.001, respectively). CONCLUSIONS: In the current Japanese real-world registry, there were a high proportion of patients with low body weight, who had a higher risk for major bleeding and mortality without significant excess risk for recurrent VTE.