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Background Post thrombotic syndrome is a frequent complication of deep venous thrombosis, associated with high morbidity. Treatments currently available are invasive. Pulsed cavitational ultrasound therapy (PCUT) is a new technique to destroy remotely soft tissue. We demonstrated that PCUT was able to recanalize non-invasively in in-vitro model of human blood clot. Purpose We aim to test the safety and efficacy of venous recanalization by non-invasive PCUT in vivo swine model of acute venous thrombosis. Methods All the experiments were performed on White large X Landrace swine. We induced an acute femoral deep venous thrombosis by using endovascular approach combined with local injection of thrombin. A 3 cm length occlusive thrombosis was obtained after 2 hours. Swine were divided in three groups: one with PCUT without follow-up (n = 11), one with PCUT and follow-up at 14 days (n = 8), and a control group also followed for 14 days (n = 5). Acutely and during follow up all swine received curative anticoagulation. To achieve PCUT, a 2.25 MHz transducer (Imasonic©) centered by a linear probe was used and cavitation was obtained in the centre of the vein. Effectiveness of recanalization was evaluated by echo-Doppler and phlebography. Safety was assessed by Doppler ultrasound and by histological analysis of vein, artery and lungs. Results Among the 24 swine, we obtained 22 occlusive venous thromboses and 2 partials. The median length of the thrombus was 26 ± 4.4 mm. Acutely, thrombosis recanalization was obtained among the 19 swine with PCUT with median treatment duration of 33 min. After a 14-day follow-up, 75% of recanalisation remains permeable vs. 0% of vein permeable in the no therapy group (P = 0.008). Residual diameter was 2.6 ± 1.2 mm, 50% of the venous diameter. No embolism or pulmonary infarction was observed in all pigs ( Fig. 1 ). Conclusion We have demonstrated in vivo the safety and the efficacy of PCUT for non-invasive venous recanalization, persistent after 2 weeks.

Objectives Histotripsy has been shown promising for non-invasive treatment of deep venous thrombosis. Important challenges remain, however, to perform a safe and accurate treatment in human patients. The objective of this work was to evaluate 1) the feasibility of this approach assisted by a robot to recanalize effectively a venous thrombosis in vivo and 2) the safety or our device on venous wall injury and risk of pulmonary embolism. Methods A femoral venous thrombosis of 9 pigs weighing 49.6 kg was systematically created. To obtain occlusive thrombosis, we used a double jugular and femoral approach to position the balloons. A thrombosis was obtained after 2 h of stasis associated with 50 IU of human thrombin. A 2.25 MHz transducer (Imasonic©) centered by a linear probe (SL10-2, SuperSonic Imagine©) was used and cavitation was obtained in the center the vein. After manual determination of the thrombus, a 6-axis robotic arm was used to automatically move the transducer along the thrombus trajectory. Success of recanalization was evaluated by the flow restoration, evaluated with phlebography and colour-Doppler imaging ( Fig. 1 ). The safety was assessed by local hematoma research with ultrasound imaging and histological analysis of the lungs for embolism. Results 7 occlusive and 2 subocclusive venous thrombosis were obtained with a mean length of 2.8 ± 0.4 cm. Among them, only 7 were accessible for recanalization because 2 thromboses were too deep (>3 cm). Recanalization was systematically obtained among the 6 occlusive cases, with improvement of flow in the case of partial thrombosis. No extravasation of contrast product or hematoma was observed with radioscopy and ultrasound imaging. The pulmonary arterial tree wasmacroscopically free from embolism. Conclusion Thrombotripsy performed at high frequency (2.25 MHz) is an effective and safe tool to enable non-invasive and thrombolytic venous recanalization.

Background The DENERHTN trial confirmed the daytime ambulatory systolic blood pressure (dASPB) lowering efficacy of renal denervation (RDN) added to a standardized stepped-care antihypertensive treatment (SSAHT) for resistant hypertension at 6 months. This post-hoc analysis assessed the impact of abdominal aortic calcifications (AAC) on the hemodynamic and renal response to RDN at 6 months. Methods A total of 106 patients with resistant hypertension were randomly assigned to RDN + SSAHT, or the same SSAHT alone (control group). Total AAC volume was measured from the aortic hiatus to the iliac bifurcation, blind to randomization, with semiautomatic software, on the pre-randomization non-contrast abdominal CT-scans of 90 patients and expressed as tertiles. Results The baseline-adjusted difference in the change in dASBP from baseline to 6 months between the RDN and control groups was −10.1 mmHg (P = 0.0462) in the lowest tertile of AAC volume and −2.5 mmHg (P = 0.4987) in the two highest tertiles of AAC volume. Estimated glomerular filtration rate (eGFR) remained stable at 6 months in the patients with the lowest tertile of AAC volume who underwent RDN (+2.5 mL/min/1.73 m2) but decreased in the control group (−8.0 mL/min/1.73 m2, P= 0.0148). In the two highest tertiles of AAC volume, eGFR decreased similarly in the RDN and the control groups (P = 0.2640). Conclusion RDN plus SSAHT resulted in a larger decrease in dASBP than SSAHT alone in patients with a lower AAC burden than in those with a higher AAC burden. This larger decrease in dASBP was not associated with a decrease in eGFR.