Objective To design a novel stentless porcine aortic bioprosthesis and test the feasibility and its function in vitro after the valve was implanted by a modified method. Methods Six stentless porcine aortic bioprosthesis were divided into two groups according to different implantation, single layer suture group: new improvement stentless porcine aortic bioprosthesis sutured with single layer was implanted; double layer suture group: stentless porcine aortic bioprosthesis developmented by our laboratory used double layer suture was implanted. Each group contained three scales: 23 mm ,25 mm and 27 mm. Analogue ex vivo aortic valve replacement was performed , the feasibility of the new implantation was detected. Effective orifice area, transvalvular pressure gradient and regurgitation ratio were recorded at the cardiac output of 2.0 L/min, 3.5 L/min, 5.0 L/min and 7.0 L/min under the guideline of International Organization for tandardization （ISO）5840. Results The average aortic valve implantation time used for single layer suture and tradition double layer suture were 50 min and 70 min respectively. The transvalvular pressure gradient in the single layer suture group were significantly lower than those in double layer suture group under the flow of 5.0 L/min in 23 mm valve and 27 mm valve （13.51±0.51 mm Hg vs. 14.44±0.99 mm Hg, 7.36±0.19 mm Hg vs. 7.53±0.28 mm Hg；P＜0.01）;and the effective orifice area in the single layer suture group were larger than those in double layer suture group in the same case(1.87±0.06 cm2 vs. 1.76±0.08 cm2, 2.26±0.07 cm2 vs. 2.16±0.05 cm2；P＜0.01). There was no statistically difference in other parameters between both groups. Conclusion The novel design of new improvement stentless porcine aortic bioprosthesis used single layer suture has good hemodynamic characteristics as the nature structure . The modified suture method decrease the implantation time.Nemerical data of the evaluation in vitro show that the difference between single layer suture group and double layer suture group in effective orifice area,transvalvular pressure gradient and regurgitation ratio haveno statistical significance. This experiment is the foundation of the animal and clinical experiment in the future.
Objective To investigate surgical treatment and evaluate the curative effect in patients with moderate to severe ischemic mitral regurgitation (IMR). Methods The clinical data of the patients with coronary heart disease complicated with moderate to severe IMR who agreed to receive surgical treatment from June 2014 to June 2019 in our hospital were analyzed retrospectively. The patients were divided into two groups: a coronary artery bypass grafting (CABG) group and a CABG+mitral valve surgery (MVS) group. The preoperative and postoperative clinical data between the two groups were compared. Results Finally 105 patients were collected, including 75 males and 30 females, aged 40-79 (62.70±7.90) years. There were 34 patients in the CABG group, and 71 patients in the CABG+MVS group including 2 patients of mitral valvuloplasty and 29 patients of mitral valve replacement. Among the 105 patients, 5 died during the perioperative period and 2 died in 3 months after operation, all of whom were from the CABG+MVS group. There was no statistical difference in perioperative and postoperative 3-month mortality rate between the two groups (P=0.14). Eighty-seven patients were followed up in the medium and long term. There was no statistical difference in the degree of preoperative mitral insufficiency (MI) (P=0.59) and left atrium diameter (P=0.51) between the two groups, but the degree of postoperative MI in the CABG group was significantly higher than that in the CABG+MVS group (P<0.01). However, the left atrium diameter in the CABG group was significantly smaller than that in the CABG+MVS group (P<0.01). Paired analysis showed that systolic pulmonary artery pressure, left ventricular end-diastolic diameter, left ventricular end-systolic diameter, left ventricular ejection fraction and MI were significantly improved after operation (P<0.01); left atrium diameter was significantly improved after operation in the CABG group (P<0.01), but there was no statistical difference before and after operation in the CABG+MVS group (P=0.10). Conclusion For patients with moderate to severe IMR, CABG with mitral valve treatment can improve left ventricular remodeling, but can not significantly improve left atrial remodeling. Whether performing mitral valve treatment during CABG should be cautious. CABG alone is a safe and effective scheme for elderly patients with poor physical condition and low life expectancy.