Peri-Balloon Leak Flow Velocity Assessed by Intra-Cardiac Echography Predicts Pulmonary Vein Electrical Gap　- Intra-Cardiac Echography-Guided Contrast-Free Cryoballoon Ablation.

BACKGROUND: The use of iodine contrast agents is one possible limitation in cryoballoon ablation (CBA) for atrial fibrillation (AF). This study investigated intracardiac echography (ICE)-guided contrast-free CBA.Methods and Results:The study was divided into 2 phases. First, 25 paroxysmal AF patients (Group 1) underwent CBA, and peri-balloon leak flow velocity (PLFV) was assessed using ICE and electrical pulmonary vein (PV) lesion gaps were assessed by high-density electroanatomical mapping. Then, 24 patients (Group 2) underwent ICE-guided CBA and were compared with 25 patients who underwent conventional CBA (historical controls). In Group 1, there was a significant correlation between PLFV and electrical PV gap diameter (r=-0.715, P<0.001). PLFV was higher without than with an electrical gap (mean [±SD] 127.0±28.6 vs. 66.6±21.0 cm/s; P<0.001) and the cut-off value of PLFV to predict electrical isolation was 105.7 cm/s (sensitivity 0.700, specificity 0.929). In Group 2, ICE-guided CBA was successfully performed with acute electrical isolation of all PVs and without the need for "rescue" contrast injection. Atrial tachyarrhythmia recurrence at 6 months did not differ between ICE-guided and conventional CBA (3/24 [12.5%] vs. 5/25 [20.0%], respectively; P=0.973, log-rank test). CONCLUSIONS: PLFV predicted the presence of an electrical PV gap after CBA. ICE-guided CBA was feasible and safe, and could potentially be performed completely contrast-free without a decrease in ablation efficacy.

Ultrafast beam pattern modulation by superposition of chirped optical vortex pulses.

As an extension of pulse shaping techniques using the space-time coupling of ultrashort pulses or chirped pulses, we demonstrated the ultrafast beam pattern modulation by the superposition of chirped optical vortex pulses with orthogonal spatial modes. The stable and robust modulations with a modulation frequency of sub-THz were carried out by using the precise phase control technique of the constituent pulses in both the spatial and time/frequency domains. The performed modulations were ultrafast ring-shaped optical lattice modulation with 2, 4 and 6 petals, and beam pattern modulations in the radial direction. The simple linear fringe modulation was also demonstrated with chirped spatially Gaussian pulses. While the input pulse energy of the pulses to be modulated was 360 [Formula: see text]J, the output pulse energy of the modulated pulses was 115 [Formula: see text]J with the conversion efficiency of [Formula: see text] 32%. Demonstrating the superposition of orthogonal spatial modes in several ways, this ultrafast beam pattern modulation technique with high intensity can be applicable to the spatially coherent excitation of quasi-particles or collective excitation of charge and spin with dynamic degrees of freedom. Furthermore, we analyzed the Poynting vector and OAM of the composed chirped OV pulses. Although the ring-shaped optical lattice composed of OV pulse with topological charges of [Formula: see text] is rotated in a sub-THz frequency, the net orbital angular momentum (OAM) averaged over one optical period is found to be negligible. Hence, it is necessary to require careful attention to the application of the OAM transfer interaction with matter by employing such rotating ring-shaped optical lattices.

Successful staged management of a spontaneous iliac vein rupture associated with May-Thurner syndrome: a case report.

BACKGROUND: Spontaneous iliac vein ruptures have only been reported in approximately 50 cases. An accurate preoperative diagnosis is difficult even with contrast-enhanced computed tomography (CT), and the operative mortality and morbidity rates are quite high. The cause of spontaneous iliac vein ruptures and their optimal diagnosis and management remain unclear. CASE SUMMARY: A 69-year-old woman without a history of prior trauma presented with low back pain, left lower limb swelling, and hypovolaemic shock. An initial contrast-enhanced CT revealed a large retroperitoneal haematoma without arterial extravasation. Her blood pressure dropped again under a noradrenaline administration. A second venous phase contrast-enhanced CT revealed venous extravasation in the external iliac vein with a suspected compression of the common iliac vein (May-Thurner syndrome) and deep vein thrombosis (DVT). Her haemodynamics were stabilized whilst a laparotomy was arranged. An inferior vena cava (IVC) filter was placed due to concerns about rebleeding with initiating anticoagulation therapy. Given the failed conservative management, elective endovascular treatment (EVT) was performed including percutaneous Fogarty venous thrombectomy and placement of self-expanding and covered stents. After the intervention, the lower limb swelling significantly improved under oral anticoagulation therapy, and the IVC filter was retrieved. At the 3-month follow-up, the lower limb swelling completely disappeared, and the contrast-enhanced CT demonstrated the complete disappearance of the retroperitoneal haematoma and DVT. DISCUSSION: This case provided not only the potential value of the venous phase contrast-enhanced CT in diagnosing a spontaneous iliac vein rupture but also the potential benefit of conservative management followed by elective EVT.