Objective To investigate the experience of left ventricular reconstruction(LVR)in a rat model with post-infarction ventricular aneurysm. Methods A total of 35 male Sprague-Dawley (SD)rats underwent left anterior descending artery (LAD) ligation to create a left ventricular aneurysm (LVA) model following myocardial infarction. Four weeks later, 16 rats with LVA that met the inclusion criteria underwent LVR as the experiment group(LVR group). Another 10 rats with LVA underwent thoracotomy as the control group. Three days, 2 weeks, and 4 weeks after the second operation, all the rats were examined by echocardiography to evaluate the cardiac function. At the end of the study, photography and Masson’s Trichrome staining were used to evaluate the completeness of LVA resection. Results The surgical mortality of LVA and LVR generation was 11.4%(4/35)and 18.8%(3/16)respectively, with the success rate 74.3% (26/35)for LVA model and 81.3%(13/16)for LVR model. Photography and Masson’s Trichrome staining identified complete replacement of ventricular scar by patch. Three days after the second operation, echocardiography illustrated that the left ventricular end-systolic diameter (LVESD)and fractional shortening (FS) of the LVR group were significantly improved compared with the control group (LVESD 5.00±0.87 mm versus 5.90±0.92 mm, P<0.05,FS 34.20%± 6.80% versus 26.60%±6.12%, P< 0.01). The cardiac structure and function of LVR group were also significantly improved 2 weeks and 4 weeks after the second operation compared with the control group(2 weeks:left ventricular end-diastolic diameter (LVEDD)7.60±0.56 mm versus 8.50±1.08 mm,P< 0.01;LVESD 5.10±0.65 mm versus 6.69±0.89 mm,P<0.001;FS 31.90%±6.90% versus 21.10%±6.17%,P<0.001;4 weeks:LVEDD7.70±0.50 mm versus 9.10±0.89 mm,P<0.001;LVESD5.20±0.39 mm versus 7.20±0.95 mm,P<0.001;FS 31.80%±2.40% versus 20.20%±4.17%,P<0.001). Conclusions LVR rat can be used as a stable, reliable and economic screeningmodel in engineered heart tissue(EHT)research.
Objective To explore the feasibility of tissue-engineered heart valve (TEHV) reconstructed on acellularized porcine aortic valve and rabbit bone marrow stromal cells (BMSCs) in vitro. Methods Acellularized was performed in porcine aortic valve by the detergent and enzymatic extraction process . Morphological and biomechanical properties were compared between the decellularized scaffolds and the fresh valves. Rabbit BMSCs were seeded on the scaffolds. The TEHV were analyzed by light microscopy, electron microscopy and immunohistochemistry. Results Almost complete removal of the cellular components and soluble protein of valves were observed , while the construction of matrix was properly maintained. Biomechanical tests demonstrated no statistically significant change in the breaking intensity (642 ± 102 g/mm2 vs. 636 ± 127g/mm2) and breaking extensibility (62. 2%± 18. 1% vs. 54. 4%±16. 0%) in the porcine values before and after decellularization. Subsequent seeding with rabbit BMSCs on the matrix was so successful that the surface of the scaffold had been covered with a continuous monolayer cells through light microscopy and electron microscopy. Positive of α-smooth muscle actin and negative of CD31 were observed after rabbit BMSCs seeded on the matrix through immunohistochemistry. Conclusion It is feasible to reconstruct TEHV in vitro on acellularized porcine aortic valve scaffold and rabbit BMSCs.
The engineered heart tissues (EHTs) present a promising alternative to current materials for native myocardial tissue due to the unique characteristics. However, until now, the clinical application of EHTs is limited by a serial of practical problems yet. Generally, the challenges need to further optimize include biomaterials, cell sources, and strategies of revascularization or establishment of EHTs. This review focuses on the newly progress on these aspects to encourage the emergence of novel EHTs that can meet clinic requirement properly.
The engineered heart tissues (EHTs) is regarded as a hope for myocardial repair and regeneration. But a series of " bottleneck” problems, such as vascularization, hinder their clinical translation. This review focuses on the strategies to vascularization of EHTs and encourages the emergence of novel EHTs that can meet clinic requirement properly.
With the development of molecular and cellar cardiology, gene therapy to cardiovascular disease has become the hot spot and the direction of study. Now, preclinical studies on ultrasound-mediated gene delivery (UMGD) in cardiovascular disease have achieved some success, but it is still hindered by a series of practical challenges for clinical translation. Even so, UMGD still holds the promise to cardiovascular disease in gene therapy for its non-invasiveness, accuracy, safety and ability to deliver multiple genes with repeated deliveries. In this review, we will focus on the basic principle, the current development, the future prospect and drawbacks of UMGD in the therapeutic applications of cardiovascular disease.
Objective To observe the impact of collagen patches using 1-ethyl-3- (3-dimethylaminopropyl) carbod-iimide hydrochloride chemistry (EDC) to conjugate vascular endothelial growth factor (VEGF) + basic fibroblast growth factor (bFGF) or VEGF alone on the survival rate of transplanted human bone morrow mesenchymal stem cells (hBM-MSCs)in vitro and in vivo. Methods Collagen patches which were activated by EDC were used as the control group,and EDC activated collagen patches that were conjugated with VEGF or VEGF + bFGF were used as the experiment groups(VEGF group and VEGF + bFGF group). hBM-MSCs (0.5×106/patch) were used as seeding cells to construct engineered heart tissue (EHT). MTT assay was performed to assess in vitro proliferation of hBM-MSCs on 3 different collagen patches. Ventricular aneurysm model after myocardial infarction was created by left anterior descending artery (LAD) ligation in male SD rats,and EHT which were constructed with 3 different patches were used for ventricular plasty. Four weeks later,immunofluorescence staining was used to examine arteriole density (anti-α-SMA staining) and transplanted cell survival (anti-h-mitochondria staining). Results (1) hMSCs proliferation in VEGF group and VEGF + bFGF group was significantly better than that in the control group on the 2nd and 4th day after cell transplantation (P<0.05); (2) Four weeks afterEHT implantation,immunofluorescence staining for α-SMA revealed that arteriole density of VEGF group and VEGF + bFGF group was significantly higher than that of the control group (P<0.05); (3) Immunofluorescence staining forh-mitochondria showed that survival rates of transplanted hBM-MSCs of VEGF group and VEGF + bFGF group were significantly higher than that of the control group (P<0.05); (4) There was a significantly positive correlation between survival rate of hBM-MSCs and arteriole density (r 2=0.99,P=0.02). Conclusion VEGF or VEGF + bFGF conjugated collagen patch can significantly improve hBM-MSCs proliferation in vitro and enhance survival rate of transplanted hBM-MSCs by accelerating revascularization of EHT in vivo.
ObjectiveTo summarize the surgical strategy on treating mitral desease patient associated with hypertrophic obstructive cadiomyopathy (HOCM). MethodsWe retrospectively analyzed the clinical data of 17 patients with HOCM underwent surgical treatment from November 2003 to May 2015 year. There were 10 males and 7 females with a mean age of 42.2±15.5 years ranging from 7-62 years. There were 16 patients underwent modified Morrow procedure and 1 patient underwent modified Konno procedure to relieve the obstruction of left ventricular outflow tract. And different surgical treatment of mitral valve disease was implemented depending on the severity of regurgitation and under monitoring of transesophageal echocardiography. About 2 weeks after the surgery, we performed transthoracic echocardiography to evaluate the effect of operation. ResultsNo hospital death occurred and the surgery obviously improved the symptom and cardiac function in all cases. After surgery, echocardiography revealed that the mean thickness of the ventricular septum statistically decreased (P < 0.0001), the systolic anterior motion disappeared, the outflow track pressure of left ventricle statistically decreased (P < 0.0001), and the peak flow rate of left ventricle statistically decreased. However, there was no statistical difference in the change of the left ventricular ejection fraction(P=0.083). Nine patients with no mitral regurgitation (MR) or mild MR only underwent the unblock of the left ventricular outflow track, the MR decreased to mild or disappeared. Four patients with moderate or severe MR underwent mitral valve repair, and the MR decrease to mild or disappear. There were no complications occurred regarding to prosthesis implantation over the 4 patients underwent mitral valve replacement for infective endocarditis or other causes. ConclusionFor the HOCM patients with mild MR, the unblock of the left ventricular outflow track alone can effectively improve the MR. For those combined with moderate or severe MR, we should choose mitral valve repair or replacement based on individual situation of patient.