Efficacy of fenestrated atrial septal defect occulders on pulmonary hypertension dogs / 中华心血管病杂志

Objective: To explore the short-term efficacy of fenestrated atrial septal defect (ASD) occulders in the treatment of pulmonary arterial hypertension (PAH). Methods: Thirty-six healthy dogs were divided into the balloon atrial septostomy (BAS)+fenestrated ASD occulders group (n=12), BAS group (n=12) and non-septostomy group (n=12). PAH was induced by intra-atrial injection of dehydrogenized monocrotaline (1.5 mg/kg) in all dogs. Animals in the BAS+fenestrated ASD occulders group underwent atrial septal puncture and fenestrated ASD occulders implantation. Animals in the BAS group underwent balloon atrial septostomy. The non-septostomy group received no surgical intervention. The hemodynamic indexes and blood N-terminal pro-B-type natriuretic peptide (NT-proBNP) of dogs were measured before modeling, 2 months after modeling, 1, 3, and 6 months after surgery, respectively. Echocardiography was performed to observe the patency of the shunt and atrial septostomy of the dogs in the BAS+fenestrated ASD occulders group and BAS group at 1, 3, and 6 months after surgery. Three dogs were sacrificed in each group at 1, 3, and 6 months after surgery, respectively. Atrial septal tissue and fenestrated ASD occulders were removed to observe the patency and endothelialization of the device. Lung tissues were obtained for hematoxylin-eosin (HE) staining to observe the inflammatory cells infiltration and the thickening and narrowing of the pulmonary arterials. Results: Among 36 dogs, 2 dogs died within 24 hours after modeling, and 34 dogs were assigned to BAS+fenestrated ASD occulders group (n=12), BAS group (n=11), and non-septostomy group (n=11). Compared with BAS group, the average right atrial pressure (mRAP) and NT-proBNP of dogs in the BAS+fenestrated ASD occulders group were significantly reduced at 3 months after surgery (P<0.05), and the cardiac output (CO) was significantly increased at 6 months after surgery, arterial oxygen saturation (SaO2) was also significantly reduced (P<0.05). Compared with non-septostomy group, dogs in the BAS+fenestrated ASD occulders group had significantly lower mRAP and NT-proBNP at 1, 3, and 6 months after surgery (P<0.05), and higher CO and lower SaO2 at 6 months after surgery (P<0.05). Compared with the non-septostomy group, the dogs in the BAS group had significantly lower mRAP and NT-proBNP at 1 month after surgery (P<0.05), and there was no significant difference on mRAP and NT-proBNP at 3 and 6 months after surgery (P>0.05). Echocardiography showed that there was a minimal right-to-left shunt in the atrial septum in the BAS group at 1 month after the surgery, and the ostomy was closed in all the dogs in the BAS group at 3 months after the surgery. There was still a clear right-to-left shunt in the dogs of BAS+fenestrated ASD occulders group. The shunt was well formed and satisfactory endothelialization was observed at 1, 3 and 6 months after surgery. The results of HE staining showed that the pulmonary arterials were significantly thickened, stenosis and collapse occurred in the non-septostomy group. Pulmonary microvascular stenosis and inflammatory cell infiltration in the pulmonary arterials were observed in the non-septostomy group. Pulmonary arterial histological results were comparable between BAS+fenestrated ASD occulders group and non-septostomy group at 6 months after surgery . Conclusions: The fenestrated ASD occulder has the advantage of maintaining the open fistula hole for a longer time compared with simple balloon dilation. The fenestrated ASD occulder can improve cardiac function, and it is safe and feasible to treat PAH in this animal model.

Impact of transcatheter aortic valve replacement on renal function in patients with severe aortic stenosis / 中华心血管病杂志

Objective: To explore the impact of transcatheter aortic valve replacement (TAVR) on renal function in patients with severe aortic stenosis. Methods: This is a single-center retrospective study. Consecutive patients with severe aortic valve stenosis and received TAVR in Zhongshan Hospital from December 2014 to December 2019 were included. The patients were divided into four groups according to the estimate glomerular filtration rate (eGFR) measured at one day before TAVR, namely eGFR>90 ml·min-1·1.73m-2 group, 60<eGFR≤90 ml·min-1·1.73m-2 group, 30<eGFR≤60 ml·min-1·1.73m-2 group and eGFR≤30 ml·min-1·1.73m-2 group. The patients were also divided into acute renal function recovery (AKR) group, acute kidney injury (AKI) group and no change in renal function group according to renal function changes at 72 hours after TAVR. AKR was defined as eGFR increased by more than 25% of the baseline value at 72 hours after TAVR, and AKI was defined as eGFR decreased more than 25% of the baseline value at 72 hours after TAVR. The clinical data of each group were compared, and multivariate logistic regression analysis was performed to analyze the determinants responsible for renal function changes after TAVR. Results: A total of 217 patients were enrolled in this study. The age was (76.7±7.4) years and there were 86 females. The Society of Thoracic Surgeons score was (9.5±5.8). The proportions achieved AKR after TAVR were 0, 30.2% (35/116), 58.6% (41/70) and 75.0% (9/12) respectively in eGFR>90 ml·min-1·1.73m-2 group, 60<eGFR≤90 ml·min-1·1.73m-2 group, 30<eGFR≤60 ml·min-1·1.73m-2 group and eGFR≤30 ml·min-1·1.73m-2 group. A total of 3 patients (1.4%) suffered AKI, including 2 patients in 30<eGFR≤60 ml·min-1·1.73m-2 group and 1 patient in 60<eGFR≤90 ml·min-1·1.73m-2 group. The incidence of AKI in eGFR<60 ml·min-1·1.73m-2 group was 2.4% (2/82). Among the 217 patients, AKR occurred in 85(39.2%) patients, 3(1.4%) experienced AKI and renal function remained unchanged in 129 (59.4%) patients post TAVR. Body mass index (BMI), left ventricular end diastolic dimension (LVEDD) and preoperative eGFR were statistically different between the 3 groups (P<0.05). Multivariate logistic regression analysis showed that BMI (OR=5.54, 95%CI 1.04-29.58, P=0.045), preoperative LVEDD (OR=1.22, 95%CI 1.09-1.38, P=0.001) and preoperative eGFR (OR=2.23, 95%CI 2.04-2.55, P=0.004) were associated with non-AKR post TAVR. Conclusions: After TAVR, most patients show no change or improvement of renal function. BMI, preoperative LVEDD and eGFR are related to renal function change after TAVR.