Propensity-matched comparison of balloon-expandable and self-expanding valves for transcatheter aortic valve replacement in a Chinese population.

Background: Balloon-expandable valves (BEV) and self-expanding valves (SEV) for transcatheter aortic valve replacement (TAVR) have shown promising results in Western populations. Herein, we comparatively evaluated their hemodynamics and early clinical outcomes in a Chinese population. Methods: One hundred seventy-eight patients with symptomatic aortic stenosis who had undergone transfemoral TAVR using SEV (n=153; Venus-A, 97; VitaFlow, 56) or BEV (n=25; Sapien3) from September 2020 to April 2021 were retrospectively enrolled, and 25 pairs were propensity-score matched for 10 baseline variables. The primary study outcomes were aortic valve hemodynamics and postoperative complications at discharge and 3-month follow-up. Results: TAVR was successful in all patients. Compared with SEV group, the BEV group had similarly distributed baseline characteristics, procedural time, hospital stay, new pacemaker implantation, and paravalvular regurgitation grade. We also observed that the BEV group had lower rates of balloon pre-dilation (60% vs. 92%, P=0.018), post-dilation (0 vs. 20%, P=0.050) and second valve implantation (0 vs. 24%, P=0.022); higher mean transaortic gradient (14.3±6.1 vs. 10.8±4.9, P=0.030) and proportion of patients with elevated gradients (20% vs. 0, P=0.050) at discharge; and similar rehospitalization, mean transaortic gradient, new pacemaker implantation, and paravalvular regurgitation grade than the SEV group at the 3-month follow-up. There were no deaths in either group. However, the proportion of patients with elevated gradients in SEV group was higher at 3 months than before discharge (24% vs. 0, P=0.022). Conclusions: BEV and SEV for transfemoral TAVR appear comparably safe and effective, with high device success and favorable 3-month clinical outcomes. However, the transaortic gradient and new pacemaker implantation in the SEV group increased during follow-up, warranting larger studies with longer-term follow-up.

A novel double-balloon catheter for percutaneous balloon pulmonary valvuloplasty under echocardiographic guidance only.

BACKGROUND: Percutaneous balloon pulmonary valvuloplasty (PBPV) is the procedure of choice for uncomplicated severe or symptomatic pulmonary stenosis. Echocardiography (echo)-guided PBPV can completely avoid the use of radiation and contrast agents compared to fluoroscopy-guided PBPV. Although we have confirmed that echo-guided PBPV is feasible in humans, the poor visibility of the traditional catheter under echo greatly limits the promotion of this new technology. METHODS: We produced a novel double-balloon catheter to make the catheter easy to be detected by echo through adding a guiding balloon at the distal end of the catheter. Echo-guided PBPV was performed on thirty healthy swine using either a novel catheter or a traditional catheter to evaluate the feasibility and safety of the novel double-balloon catheter. The feasibility was evaluated by the success rate of balloon inflation at the pulmonary valve annulus and the operating time. The safety was evaluated by the frequency of balloon slippage and the incidence of complications. RESULTS: There were no significant between-group differences in terms of weight and the ratio of balloon diameter to pulmonary annulus diameter. The success rate was 93.3% and 60% in the novel and traditional groups, respectively. The novel group had significantly (p<0.05) lower mean procedure time (6.33±6.86min vs 24.8±9.79min) and lower frequency of balloon slippage (0.07±0.26 vs 0.53±0.52), arrhythmia (0.07±0.26 vs 0.47±0.52), and tricuspid regurgitation (6.7% vs 40%) than the traditional group. No myocardial hematoma or pericardial tamponade occurred in the novel catheter group. CONCLUSION: Although further studies and improvements are required, the study results indicate that the novel double-balloon catheter for echo-guided PBPV is feasible and safe.

A Novel Wire Is Effective for Echo-Guiding Percutaneous Atrial Septal Defect Closure: A Preclinical Study.

Objective: To assess the effectiveness of a novel ultrasound wire for echo-guiding percutaneous atrial septal defect (ASD) closure in a sheep model. Methods: After right lateral thoracotomy, ASDs were created in 20 sheep by transseptal needle puncture followed by balloon dilatation. Animals were evenly randomized into 2 groups to undergo ASD closure using echography as the only imaging tool with either COOK wire (control group) or new ultrasound wire (study group). The total procedural time, passing time (time needed for the guide wire to enter the left atrium), frequency of delivery sheath dropping into the right atrium, frequency of arrhythmias, and 1-week rate of complications were compared between the two groups. Results: All animals survived defect creation procedures uneventfully. ASD devices were successfully implanted in all sheep. Compared with the control group, the study group had significantly (P < 0.05) lower mean procedure time (15.36 ± 4.86 versus 25.82 ± 7.85 min), lower mean passing time (2.69 ± 0.82 versus 5.58 ± 3.34 min), lower frequency of the guide wire dropping into the right atrium (0% versus 40%), and lower frequency of atrial (4.41 ± 2.61 versus 9.60 ± 3.68) or ventricular premature contractions (0.75 ± 0.36 versus 1.34 ± 0.68), respectively, without serious complications up to one week. Conclusion: The novel ultrasound specialized guide wire was effective in echo-guiding percutaneous ASD closure.

Hybrid Balloon Valvuloplasty for the Treatment of Severe Congenital Aortic Valve Stenosis in Infants.

BACKGROUND: Surgical or percutaneous interventional treatment of severe congenital aortic valve stenosis (CAS) in early infancy remains challenging. This single-center, retrospective study analyzed midterm outcomes of a hybrid balloon valvuloplasty procedure through the ascending aorta by way of median sternotomy, including cases with improved technique. METHODS: Included were 45 consecutive infants (aged <90 days) with CAS and selected for biventricular repair who underwent hybrid balloon valvuloplasty in a hybrid or ordinary operating room from October 2010 to March 2016. Patients were assessed at 1, 3, 6, and 12 months and yearly thereafter. RESULTS: Hybrid balloon valvuloplasty was successful in all patients, with the last 8 treated in an ordinary operating room under only echocardiography guidance with a new sheath. Thirty-two patients were successfully rescued from low heart rate or left ventricular systolic dysfunction, or both, by cardiac massage under direct visualization; none required cardiopulmonary bypass. The degree of new aortic insufficiency was mild in 7 patients and changed from mild to moderate in 1 patient. Aortic valve pressure gradient decreased from 70.6 ± 17.5 mm Hg preoperatively to 15.2 ± 4.2 mm Hg immediately postoperatively (p < 0.001). Fluoroscopy time was 4.8 ± 2.3 minutes. At a median of 32.1 months (range, 1 to 68 months) follow-up, all patients were alive and healthy. Aortic valve pressure gradient remained low (19.1 ± 5.2 mm Hg). Left ventricular ejection fraction increased from 0.515 ± 0.134 (range, 0.21 to 0.70) preoperatively to 0.633 ± 0.035 (range, 0.58 to 0.75; p < 0.001). No aortic insufficiency developed, and no patient required reintervention. CONCLUSIONS: For infants with severe CAS, hybrid balloon valvuloplasty through the ascending aorta by way of a median sternotomy appears efficacious and safe up to midterm follow-up.

[Effect of the biodegradable chitosan external stent on the early changes in the rabbit vein grafts].

OBJECTIVES: To investigate the effect of chitosan biodegradable external stent (CES) on the early changes of rabbit vein graft (VG). METHODS: Rabbit vein grafting models were divided into S group (with perivenous CES) and NS group (without perivenous CES). The VG were harvested in 1 week, 2 weeks, 4 weeks after operation, respectively. The expression of proliferating cell nuclear antigen (PCNA) was used for evaluating the proliferation of the smooth muscle cell (SMC). The thickness, area of neointima and media of the VG were calculated by computer imaging analysis system. RESULTS: CES began to degrade in 2 weeks after operation. The thickness, area of both neointima and media of the VG in S group, increased mildly in 1 week after operation, and kept steady in 1 or 2 weeks after grafting, which was significantly less than NS group (both P < 0.01), then increased mildly in 4 weeks after grafting but still less than NS group (P < 0.05). The expression of PCNA of SMC decreased significantly in comparison with NS group though increasing mildly in four weeks after operation. Both neointimal formation and cell proliferation in the graft wall were significantly reduced by external stenting as compared to the results with unstented grafts. CONCLUSIONS: CES may reduce early intimal and medial hyperplasia, and may be beneficial in improving the long term patency of the VG. The biodegradable characteristics of the CES may influence its effect.