Objective To study the protective effect of exogenous matrix metalloproteinases9(MMP-9) inhibitor Doxycycline against lung injury during cardiopulmonary bypass(CPB) in dogs. Methods Twenty healthy mongrel puppies(weighed 10 -12 kg) were divided into control group (n=10) and experimental group(n=10) with random number table. In control group, no measure was taken to protect lung before and after CPB. In experimental group, the feeding food was mixed with Doxycycline (30 mg/kg, body weight) daily for three days before operation. Enzymelinked immunosorbent assay(ELISA) was used to measure the plasma concentration of MMP-9. Hemodynamic and respiratory parameters in two groups were monitored. The preoperative and postoperative alveolararterial oxygen partial pressure difference (A-aDO2) and respiratory index(RI) were calculated. The myeloperoxidase（MPO）activity of bronchoalveolar lavage fluid（BALF）was determined by colorimetry. The total protein of BALF was measured by Coomassie Brilliant Blue G-250. After CPB, light microscope and electronic microscope were used to observe the morphological changes of lung tissue. The dry to wet weight index(W/D) was calculated. Results In both groups, the plasma concentrations of MMP-9 increased significantly as the time of CPB prolonged. The plasma MMP-9 at 150 min and 270 min after CPB in experimental group decreased significantly than those in control group (9.45±5.29 [CM(159mm]ng/ml vs. 18.66±5.90 ng/ml,t=3.664, P=0.005;16.63±2.90 ng/ml -vs.26.17±5.96 ng/ml, t=5.216, P=0.001). MPO activity, total protein of BALF, W/D, postoperative A-aDO2 and RI in experimental group decreased significantly than those in control group. There were significant differences between two groups（t=5.622,P=0.000; t=5.081, P=0.001; t=2.266, P=0.050; t=4.927, P=0.001; t=6.679,P=0.000）. The lung histopathology and electronic microscope showed that the lung injury reduced significantly. Conclusion Doxycycline plays a role in lung protection by inhibiting the secretion of MMP9, reducing the degradation of cell basement membrane, pulmonary neutrophil infiltration and pulmonary edema. Key words: Cardiopulmonary bypass; Acute lung injury; Matrix metalloproteinase; Doxycycline; Lung protection
ObjectiveTo assess the early outcome of transapical transcatheter aortic valve replacement (TAVR) for patients with aortic insufficiency. MethodsThe patients with aortic valvular disease who underwent transapical TAVR from October 2020 to October 2022 in the Department of Cardiac and Vascular Surgery, the First Affiliated Hospital of Anhui Medical University were enrolled in the current retrospective study. The patients with aortic stenosis were assembled in a group A, and the patients with aortic insufficiency were assembled in a group B. The improvements of heart function and complications were assessed for the two groups. ResultsA total of 56 patients were enrolled, including 32 males and 24 females with an average age of 73.34±5.10 years. There were 31 patients in the group A and 25 patients in the group B. There was no statistical difference between the two groups in the age, gender, height, weight, hypertension, coronary artery disease, peripheral vascular disease, chronic obstructive pulmonary disease, renal disorder or classification of heart function (P>0.05). Also, there was still no statistical difference in the rate of permanent peacemaker implants, emergent open surgery, valve re-implants, or perivalvular leakage (P>0.05). After TAVR, the left ventricular diastolic diameter, left ventricular ejection fraction, complicated moderated mitral and tricuspid regurgitation were significantly improved in both groups compared with preoperative findings (P<0.05); however, there was no statistical difference in these parameters between groups (P>0.05). ConclusionInterventional valve (J-Valve) in the treatment of patients with aortic insufficiency through transapical TAVR significantly improves cardiac function and reduces functional valve regurgitation.
ObjectiveTo explore the effect of pulmonary hypertension on the clinical efficacy of Cox Maze Ⅳ procedure in treating atrial fibrillation (AF) patients with valvular heart disease.MethodsThe clinical data of 84 patients who received cardiac valve replacement and Cox Maze Ⅳ ablation in our hospital from July 2017 to January 2020 were retrospectively analyzed. According to the estimation of pulmonary artery pressure (PAP) by ultrasound, the patients were divided into two groups: a group A (PAP<45 mm Hg, 20 males, 26 females with an average age of 59.1±7.8 years) and a group B (PAP≥45 mm Hg, 15 males and 23 females with an average age of 58.5±8.5 years). The PAP was less than 70 mm Hgin all patients. A systematic follow-up review was performed for 6 months after operation. The recovery and recurrence rate of sinus rhythm after surgical ablation were compared between the two groups, and the efficacy was analyzed.Results(1) All the patients completed the operation successfully, and there was no statistical difference in the ablation time between the two groups (P>0.05); no patients died of pulmonary infection after the operation, and one patient underwent implantation of a permanent pacemaker due to conduction block. (2) At the end of the operation and 3 months after the operation, the conversion rate of AF in the group A was 91.3% (42 patients) and 82.6% (38 patients), respectively, and in the group B was 89.5% (34 patients) and 73.7% (28 patients), respectively (P>0.05). The conversion rate of AF was 82.6% (38 patients) in the group A and 63.2% (24 patients) in the group B at 6 months after operation (P=0.043). Binary logistic regression analysis showed that PAP≥45 mm Hg had a significant effect on the long-term effect of surgical Maze procedure in treating AF patients with valvular heart disease [P=0.014, OR=5.661, 95%CI (1.429, 22.432)].ConclusionPAP may be an influencing factor for the long-term effect of surgical Maze procedure in treating AF patients with valvular heart disease. Although the long-term recurrence rate of AF in the moderate pulmonary hypertension group is higher than that in the group A, the overall effect is still safe and effective; therefore it is still worth promoting in clinical application.
Objective To investigate the feasibility and early efficacy of transapical transcatheter aortic valve replacement (TAVR) combined with transcatheter mitral valve edge-to-edge repair (TEER) in patients with high-risk aortic valve lesions combined with severe mitral regurgitation. Methods The clinical data of patients who underwent "one-stop" transapical TAVR+TEER in our hospital from August 2022 to October 2023 were retrospectively analyzed. Results Five patients were collected, including 3 males and 2 females with a mean age of 66.6±1.8 years. Four patients had aortic valve insufficiency combined with mitral regurgitation and one had aortic valve stenosis and insufficiency combined with mitral regurgitation. All patients successfully completed transapical TAVR+TEER, and the immediate postoperative echocardiographic results revealed that none of them had more than mild perivalvular leakage and mitral regurgitation, and the prosthetic valves were in good position and function. At 1 week postoperatively, echocardiographic results showed 5 patients with no displacement of the prosthetic valve, detachment of the mitral clip, or damage to the leaflets. At 1 month postoperatively, cardiac function was improved to varying degrees in 4 patients, and 1 patient died of multiorgan failure. At 2 months postoperatively, 1 patient died of cerebrovascular accident, and at 3 months postoperatively the echocardiographic results of the remaining 3 patients revealed that there was no more than mild perivalvular leakage or mitral regurgitation, and the patients' postoperative cardiac function and daily life ability were significantly improved. Conclusion In high-risk aortic valve lesions combined with severe mitral regurgitation, "one-stop" transapical TAVR+TEER is feasible with favorable early efficacy and safety.