ABSTRACT
Objective To investigate the effects of calcium - dependent and calcium - independent in myosin light chain(MLC)dephosphorylation on pulmonary hemodynamics and right ventricular remodeling,and to observe whether there is a superimposition effect while intervention is conducted in two ways at the same time. Methods Ac-cording to random number table,50 rats were divided into 5 groups:sham operation group,model group,3 mg/(kg·d) ML - 7[MLC kinase(MLCK)inhibitor]treating group(M group),20 mg/(kg·d)Fasudil(Rho kinase inhibitor) treating group(F group)and 3 mg/(kg·d)ML - 7 plus 20 mg/(kg·d)Fasudil treating group(M + F group). The shunt between the abdominal aorta and inferior vena cava was used to establish rat models of pulmonary hypertension in-duced by high pulmonary flow in group of C and the experimental groups. The sham operation group was given a sham operation. MLCK and Rho kinase inhibitor were administrated intraperitoneally to rats with the shunt. After 8 weeks of shunting,mean right ventricular pressure(MRVP),mean pulmonary arterial pressure(MPAP),right ventricular hyper-trophy index(RVHI)and width of inferior venacava were evaluated by the right cardiac catheterization procedure. Results Compared with the sham operation group,MRVP,MPAP,and RVHI were obviously elevated in the model group [(2. 65 ±0. 57)kPa vs(4. 19 ±0. 67)kPa;(2. 42 ± 0. 48)kPa vs(4. 04 ± 0. 61)kPa,F = 295. 368,263. 912,all P ﹤0. 01;(0. 21 ±0. 01)g/ g vs(0. 41 ±0. 03)g/ g,F =247. 024,P ﹤0. 01]. Compared with model group,the MRVP,MPAP and RVHI in M group and F group were decreased significantly[(3. 51 ± 0. 47)kPa vs(4. 19 ± 0. 67)kPa;(3. 68 ± 0. 55)kPa vs(4. 19 ±0. 67)kPa,all P ﹤0. 01;M group:(0. 29 ±0. 02)g/ g,model group:(0. 41 ± 0. 03)g/ g,F group (0. 30 ±0. 03)g/ g,F =247. 024,P ﹤0. 05]. But the MRVP,MPAP and RVHI in M group and F group were higher than those of rats in the sham operation group. The MRVP,MPAP and RVHI of M + F group were elevated much obviously compared with those of the M or F group(P ﹤0. 05). Conclusions The calcium - dependent and calcium - independent in MLC dephosphorylation can respectively restrain the development of pulmonary hypertension and right ventricular re-modeling,and the obvious additive effect can be observed when the 2 drugs are used jointly.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effects on cardiac remodeling post transcatheter closure by Amplatzer septal occluder selected by oval circumference formula in patients with atrial septal defect (ASD).</p><p><b>METHODS</b>A total of 146 patients with ASD (68 males,mean 33.5 years) treated by transcatheter closure with the Amplatzer occluder were enrolled in this study. The diameter of defects was corrected with the oval circumference formula (group A, 73 cases) or by echocardiography (group B, 73 cases). Cardiac remodeling was assessed by transthoracic echocardiography (TTE) before the procedure, 3 days, 3 months and 6 months after ASD closure.</p><p><b>RESULTS</b>The mean ASD diameter was similar between the two groups [(20.16 +/- 4.98) mm vs. (21.36 +/- 5.69) mm, P > 0.05] and the mean diameter of the selected occluder of group A was significantly smaller than that in group B [(21.95 +/- 6.78) mm vs. (25.85 +/- 6.75) mm, P < 0.05]. Procedural success rate was identical between the two groups (97.3%) and the defects were completely occluded and there was no residual shunt during the 6 months follow up period, there were also no complications during and after the procedure. The lateral diameter of right atrial (RALD), the diastolic diameter of right ventricle (RVDD), RALD/LALD, RVDD/LVDD and pulmonary diameter (PD) were significantly decreased while the lateral diameter of left atrial (LALD) and left ventricle (LVDD) were significantly increased post ASD closure in both groups. At 6 months follow up, RALD decreased by (18.63 +/- 10.59)% in group A versus (10.14 +/- 6.59)% in group B, LALD increased by (13.42 +/- 8.38)% in group A versus (9.28 +/- 4.95)% in group B and RALD/LALD ratio decreased by (26.35 +/- 11.24)% in group A versus (13.98 +/- 8.96)% in groups B (all P < 0.05).</p><p><b>CONCLUSION</b>ASD occluder selection based on the oval circumferen ce formula is superior to that made by echocardiography in terms of more favorable cardiac remodeling post ASD closure.</p>