[Treatment of patent ductus arteriosus in very preterm infants in China].

Objective: To describe the current status and trends in the treatment of patent ductus arteriosus (PDA) among very preterm infants (VPI) admitted to the neonatal intensive care units (NICU) of the Chinese Neonatal Network (CHNN) from 2019 to 2021, and to compare the differences in PDA treatment among these units. Methods: This was a cross-sectional study based on the CHNN VPI cohort, all of 22 525 VPI (gestational age<32 weeks) admitted to 79 tertiary NICU within 3 days of age from 2019 to 2021 were included. The overall PDA treatment rates were calculated, as well as the rates of infants with different gestational ages (≤26, 27-28, 29-31 weeks), and pharmacological and surgical treatments were described. PDA was defined as those diagnosed by echocardiography during hospitalization. The PDA treatment rate was defined as the number of VPI who had received medication treatment and (or) surgical ligation of PDA divided by the number of all VPI. Logistic regression was used to investigate the changes in PDA treatment rates over the 3 years and the differences between gestational age groups. A multivariate Logistic regression model was constructed to compute the standardized ratio (SR) of PDA treatment across different units, to compare the rates after adjusting for population characteristics. Results: A total of 22 525 VPI were included in the study, with a gestational age of 30.0 (28.6, 31.0) weeks and birth weight of 1 310 (1 100, 1 540) g; 56.0% (12 615) of them were male. PDA was diagnosed by echocardiography in 49.7% (11 186/22 525) of all VPI, and the overall PDA treatment rate was 16.8% (3 795/22 525). Of 3 762 VPI who received medication treatment, the main first-line medication used was ibuprofen (93.4% (3 515/3 762)) and the postnatal day of first medication treatment was 6 (4, 10) days of age; 59.3% (2 231/3 762) of the VPI had been weaned from invasive respiratory support during the first medication treatment, and 82.2% (3 092/3 762) of the infants received only one course of medication treatment. A total of 143 VPI underwent surgery, which was conducted on 32 (22, 46) days of age. Over the 3 years from 2019 to 2021, there was no significant change in the PDA treatment rate in these VPI (P=0.650). The PDA treatment rate decreased with increasing gestational age (P<0.001). The PDA treatment rates for VPI with gestational age ≤26, 27-28, and 29-31 weeks were 39.6% (688/1 737), 25.9% (1 319/5 098), and 11.4% (1 788/15 690), respectively. There were 61 units having a total number of VPI≥100 cases, and their rates of PDA treatment were 0 (0/116)-47.4% (376/793). After adjusting for population characteristics, the range of standardized ratios for PDA treatment in the 61 units was 0 (95%CI 0-0.3) to 3.4 (95%CI 3.1-3.8). Conclusions: From 2019 to 2021, compared to the peers in developed countries, VPI in CHNN NICU had a different PDA treatment rate; specifically, the VPI with small birth gestational age had a lower treatment rate, while the VPI with large birth gestational age had a higher rate. There are significant differences in PDA treatment rates among different units.

[Endovascular treatment for non-thrombotic right iliac vein compression syndrome with intravascular ultrasound].

Objective: To evaluate the clinical efficacy of endovascular treatment for non-thrombotic right iliac vein compression syndrome with intravascular ultrasound. Methods: The clinical data of 40 patients with non-thrombotic right iliac vein compression syndromereceiving intravascular ultrasound-assisted balloon dilatation combined with stent implantation from January 2012 to December 2018 were retrospectively analyzed. There were 32 males and 8 females, the average age of whom was 63 (46-81) years old. The patients were classified according to the CEAP (Clinical-Etiology- Anatomy-Pathophysiology) classification: 7 cases as C3, 18 as C4, 10 as C5 and 5 as C6. All patients underwent percutaneous right femoral vein puncture, intravascular ultrasound, and balloon dilatation combined with stentimplantation in the right iliac vein lesion location. Results: The success rate of clinical operations was 100%. There were no serious complications during the perioperative period. All patients were followed up for 4-58 months. During the follow-up period, the relief rate of limb edema was 88.6% (31/35), the pain relief rate was 86.7%(13/15), and the healing rate of ulcers was 100% (6/6). After the stent implantation, the endovascular area of the compression site was significantly enlarged (34.5mm(2)± 11.1mm(2)vs129.8 mm(2)±17.2 mm(2), P<0.001). The follow-up of color Doppler and/or anterograde angiography for deep veins of lower limb with digital subtraction angiography showed that the blood flow in the stentsweres mooth in all patients. Three cases were observed that the intimal hyperplasia led to mild in-stent restenosis, no obvious in stent restenosis (>50%). The abdominal X-ray plain film showed no obvious displacement and fracture of the stents. The venous clinical severity score (VCSS) was statistically significant (13.0±2.4 vs 6.2±2.0, P<0.001). The statistical results of short-form health surver SF-36 showed that the scores of life quality in all dimensions of the affected limb were significantly improved after operation (P=0.000). Conclusion: Intravascular ultrasound-assisted balloon dilatation combined with stent implantation is not only a safe and effective treatment for non-thrombotic right iliac vein compression syndrome, but also has a good mid-term patency rate.

[Therapeutic effect of AngioJet mechanical thrombus aspiration system combined with catheter directed thrombolysis on acute deep vein thrombosis].

Objective: To analyze the curative effect of AngioJet mechanical thrombus aspiration combined with catheter directed thrombolysis (CDT) on acute lower extremity deep vein thrombosis (LEDVT). Methods: The clinical data of 20 cases of acute LEDVT treated by AngioJet combined with CDT were analyzed. The inferior vena cava filter was implanted preoperatively, and then the thrombolysis was performed by using AngioJet. The thrombolytic catheter was placed for CDT treatment, and the thrombolysis was evaluated by review angiography. Results: All cases were successfully punctured and catheterized. The suction time was (235±75) seconds. The usage of urokinase was (180±90)*10(4) U. The differences before and after thrombolysis of ipsilateral and contralateral thigh circumference were (8.3±1.5) cm and (2.5±1.0) cm, respectively. The differences before and after thrombolysis of the ipsilateral and contralateral calf circumference were (2.4±1.0)cm and (1.5±0.7) cm, respectively. All of which had statistical significant (P<0.01). Conclusion: AngioJet mechanical thrombus aspiration system is a novel and safe method for the treatment of acute LEDVT. When used in conjunction with CDT, its advantages was more significant.