ObjectiveTo investigate the expression of tumor necrosis factor α(TNF-α ) in isolated rat heart at different time points after myocardial hypoxia/reoxygenation. MethodsThe isolated langendorff perfused rat heart model was established. Forty-eight SD rats were randomly divided into four groups: a sham group, hypoxia/reoxygenation groups including a H/R 0.5 h group, a 1 h group and a 2 h group. The heart rate(HR), the 1eft ventricular development pressure(LVDP), maximal rates of increase/decrease of the left ventricular pressure(±dp/dtmax) were continuously recorded. The concentrations of TNF-α and creatine kinase-MB(CK-MB) in myocardium, mRNA expression of TNF-α in myocardium were tested. Ultra structure of myocardium was observed under electron microscope. ResultsThe levels of LVDP, ±dp/dtmax, and HR of hypoxia/reoxygenation group were significantly lower than those in the sham group(P<0.05).The levels of TNF-α and CK-MB and the expressions of TNF-α at mRNA level in the hypoxia/reoxygenation group were higher than those in the sham group(P<0.05).There were significant differences in the above parameters among the H/R 0.5 h group, the 1 h group, the 2 h group(P<0.05).The concentrations of TNF-α and CK-MB, the mRNA expression of TNF-α were higher in the I/R 2 h group than those in the other two groups. ConclusionThe high expression of TNF-α in myocardium after myocardial hypoxia/reoxygenation in rats is related to the degree of myocardium damage and may lead to myocardial injury.
Objective To analyze the effect of monitoring and modulating the portal vein pressure and blood flow during living donor liver transplantation （LDLT） on preventing small-for-size-syndrome (SFSS). Methods Data of forty-four LDLT recipients between Oct.2007 and Oct.2008 were reviewed. Actual graft-to-recipient weight ratio（GRWR）, portal vein flow and pressure during operation and syndrome of SFSS after operation were recorded. The patients received splenectomy or splenic artery ligation according to actual GRWR, portal vein flow and pressure and WBC. Relationships between patients’ GRWR, portal vein flow, portal vein pressure and occurrence of SFSS were analyzed. Results Six patients received splenectomy and 7 patients received splenic artery ligation to decrease the portal vein flow and pressure during the operation. The portal vein flow and pressure decreased after splenectomy （Plt;0.05）. The portal vein pressure decreased （Plt;0.05） and the portal vein flow had no significant change after splenic artery ligation （P＞0.05）. No SFSS occurred after operation. Conclusion Modulation of portal vein flow and pressure by splenectomy or splenic artery ligation during LDLT operation can decrease the portal vein flow and pressure, and which can prevent the incidence of SFSS.
fter fracture of femoral neck , the head is often encountered ayascular necrosis. It was not clearwhether the causes of the necrosis was due to injury of the artery or stagnation of venous return orboth. We had observed the hmeodynamics of the blood circulation of both fermoral head of both sides in 27 cases of subcapital fracture by E. C. T. (Emission Computerized Tomography). The resultsshowed that either old, fresh, or heal fractures showed stagnation of venous return. There wasoblite...
Objective To study the effects of different levels of intra-abdominal pressure （IAP） on hemodynamics and oxygen metabolism in pig and to find the parameters early reflecting hemodynamics and oxygen metabolism of intra-abdominal hypertension （IAH）. Methods Fifteen pigs were anaesthetized, and trachea intubation and transfemoral cannula were performed then. Swan-Ganz catheters were inserted to pulmonary artery via internal jugular vein, and aeroperitoneum was set up by airing CO2. These pigs were randomly divided into three groups (5 pigs in each group) according to different levels of IAP （IAP10, IAP20, IAP30）. Hemodynamics and oxygen metabolism values were observed and recorded before airing, 6, 12, 18 and 24 hours after airing, respectively. Results There was no remarkable changes of hemodynamics and oxygen metabolism values in IAP10 group （Pgt;0.05）； When the IAP level reached 20 cm H2O, there was significant elevation （P＜0.01) in artery blood lacticacid （ABL）, and mixed venous oxygen saturation （SvO2） decreased significantly （P＜0.05) at 24 hours. When the IAP level reached 30 cm H2O, HR began to increase significantly at 18 hours after airing （P＜0.05). After 24 hours, all the indices of hemodynamics and oxygen metabolism were either significantly increased or decreased in IAP30 group. Two pigs in the group of IAP30 died during 24 hours after airing, while other pigs survived. Conclusion This study demonstrates that the hemodynamics and oxygen metabolism values begin to change in pigs when the IAP level reaches 20 cm H2O, and high level of IAP that lasted for 24 hours shows deterioration of hemodynamic and oxygenation levels. The indices of SvO2 and ABL can early reflect tissue oxygenation in IAH.
Objective To observe the midterm haemodynamic manifestation of the home made C-L pugestrut tilting disc mechanical valve in aortic valve replacement, and to evaluate its function. Methods Twenty patients underwent aortic valve replacement over 5 years were collected and divided into two groups, the C-L pugestrut group （n=10）：aortic valve was replaced by home-made C-L pugestrut tilting disc mechanical valve（21mm）; Medtronic-Hall group （n=10）：aortic valve was replaced by Medtronic-Hall mechanical valve （21mm）. The peak transprosthetic gradients （△P）, mean transprosthetic gradients （△Pm）and effective orifice area（EOA） at rest were compared between two groups. Results At rest, △P of the C-L pugestrut group and Medtronic-Hall group were 11.63±3.23mmHg vs. 9. 78±3. 35mmHg; △Pm of the C-L pugestrut group and Medtronic-Hall group were 6. 25±2. 32 mmHg vs. 5.85±2.32mmHg： EOA of the C-L pugestrut group and Medtronic-Hall group were 1.07±0.17 cm2 vs. 1.25±0.27 cm2. There was no statistically significance in △P, △Pm and EOA between two groups（P〉0.05）. Conclusions The midterm haemodynamic results of the home-made C-L pugestrut tilting disc mechanical valve show that it has comparable haemodynamic results to those of Medtronic-Hall mechanical valve ,and it has well-done function. The home-made C-L pugestrut valve is one of the reliable mechanical heart valves.
ObjectiveTo observe ocular ischemic appearance (OIA) associated with carotid artery stenosis and its effects on the hemodynamics of central retinal artery (CRA) and ophthalmic artery (OA). MethodsA total of 30 normal persons and 60 patients with carotid artery stenosis diagnosed by color Doppler flow imaging (CDFI) and digital subtraction angiography (DSA) were enrolled in this prospective study.Sixty patients were randomly divided into 2 groups:30 patients with the carotid artery stenosis degree < 60% and 30 cases with the carotid artery stenosis degree≥60%. Thirty normal persons were enrolled in the normal control group. All patients underwent a comprehensive eye examination to determine if OIA exists. The Doppler spectral patterns of CRA and OA were observed by CDFI. The peak systolic velocity (PSV), end diastolic velocity (EDV), blood vessel diameter (BVD) and resistance index (RI) of CRA and OA were measured. ResultsIn the group of the carotid artery stenosis degree≥60%, 24/30 patients (80.0%) had the ophthalmic symptoms and 9/30 patients (30.0%) had ophthalmic signs. In the group of the carotid artery stenosis degree < 60%, 9/30 patients (30.0%) had the ophthalmic symptoms and 3/30 patients (10.0%) had ophthalmic signs. For patients with≥60% stenosis, CDFI revealed a bread-like waveform of CRA, and single peak of OA instead of the typical 3-peak/2-notch waveform. For patients with < 60% stenosis, CDFI revealed a normal pattern of CRA and OA (3-peak/2-notch). The PSV(t=5.255, P=0.007) and EDV(t=4.949, P=0.005) of CRA in the stenosis≥60% group were statistically decreased compared to the normal control group, but the BVD(t=0.457, P > 0.05)and RI(t=0.213, P > 0.05)were normal. The PSV, EDV, BVD and RI of CRA in the stenosis < 60% group were normal(P > 0.05). The PSV(t=4.457, P=0.010)and EDV(t=4.588, P=0.009)of CRA in the stenosis≥60% group were statistically decreased compared to the stenosis < 60% group, but the BVD and RI were the same between these 2 groups. ConclusionPatients with carotid stenosis≥60% had a higher OIA incidence, reduced PSV, EDV of their CRA, while had no significant changes of OA hemodynamics.
The implantation of biventricular assist device (BiVAD) is more challenging than that of left ventricular assist device for the interaction in the process of multiple input and output. Besides, ventricular assist device (VAD) often runs in constant speed (CS) mode in clinical use and thus BiVAD also faces the problems of low pulsation and imbalance of blood volume between systemic circulation and pulmonary circulation. In this paper, a delay assist mode for a VAD by shortening the support time of VAD was put forward. Then, the effect of the delay mode on cardiac output, pulsation and the function of the aortic valve was observed by numerical method and the rules of hemodynamics were revealed. The research showed that compared with VAD supported in CS mode, the VAD using delay mode in systolic and diastolic period proposed in this paper could meet the demand of cardiac output perfusion and restore the function of the arterial valves. The open ratio of aortic valve (AV) and pulmonary valve (PV) increased with the time set in delay mode, and the blood through the AV/PV helped to balance the left and the right cardiac volume. Besides, delay mode also improved the pulsation index of arterial blood flow, which is conducive to the recovery of the ventricular pulse function of patients.
Objective To investigate the feasibility of a long-term left ventricular assist device placed in the aortic valve annulus for terminal cardiopathy. Methods An implantable aortic valve pump （23ram outer diameter, weighing 31g） was developed. There were a central rotor and a stator in the device. The rotor was consisted of driven magnets and an impeller, the stator was consisted of a motor coil with an iron core and outflow guide vanes. The device was implanted identical to an aortic valve replacement, occupying no additional anatomic space. The blood was delivered directly from left ventricle to the aortic root by aortic valve pump like natural ventricle, neither connecting conduits nor ＂bypass＂ circuits were necessary, therefore physiologic disturbances of natural circulation was less. Results Aortic valve pump was designed to cycle between a peak flow and zero net flow to approximate systole and diastole. Bench testing indicated that a blood flow of 7L/min with 50 mmHg（1kPa = 7.5mmHg） pressure could be produced by aortic valve pump at 15 000r/min. A diastole aortic pressure of 80mmHg could be maintained by aortic valve pump at 0L/min and the same rotating speed. Conclusions This paper exhibits the possibility that an aortic valve pump with sufficient hemodynamic capacity could be made in 23mm outer diameter, 31g and it could be implantable. This achievement is a great progress to extend the applications of aortic valve pump in clinic and finally in replacing the natural donor heart for heart transplantation. Meanwhile, this is only a little step, because many important problems, such as blood compatibility and durability, require further investigation.
ObjectiveTo investigate impact of splenectomy plus pericardial devascularization on liver hemodynamics and liver function for liver cirrhosis patients with portal hypertension. MethodsThe internal diameter, maximum velocity, minimum velocity, mean velocity, and flow volume of portal vein and hepatic artery of 42 cases of liver cirrhosis with portal hypertension were measured by Doppler ultrasonic instrument on day 1 before operation and on day 7 after operation. The free portal pressures at different phases (after open abdomen, after splenic artery ligation, after splenectomy, and after devasculanrization) were read from the disposable pressure sensor. Twenty-four healthy people through physical examination were selected as control. Results① The free portal pressure of liver cirrhosis patients with portal hypertension was decreased from (29.12±1.40) mm Hg after open abdomen to (22.71±1.21) mm Hg after splenic artery ligation, and further decreased to (21.32±1.12) mm Hg after splenectomy, but increased to (22.42±1.15) mm Hg after devasculanrization, the difference was statisticly different (all P < 0.01). ② Compared with the healthy people, for the liver cirrhosis patients with portal hypertension, the internal diameter, maximum velocity, minimum velocity, and flow volume of portal vein were significantly enlarged (all P < 0.01), which of hepatic artery were significantly reduced (all P < 0.01) on day 1 before operation; On day 7 after operation, the internal diameter of portal vein was significantly reduced (P < 0.01), the maximum velocity, minimum velocity, and mean velocity of portal vein were significantly enlarged (all P < 0.01), but the internal diameter of hepatic artery was significantly reduced (P < 0.01), the maximum velocity, minimum velocity, mean velocity, and flow volume of hepatic artery were significantly enlarged (all P < 0.01). For the liver cirrhosis patients with portal hypertension, compared with the values on day 1 before operation, the internal diameter and the flow volume of portal vein were significantly reduced (all P < 0.01) on day 7 after operation; the internal diameter, maximum velocity, minimum velocity, mean velocity, and flow volume of hepatic artery were significantly enlarged (all P < 0.01) on day 7 after operation. ③ The Child-Pugh classification of liver function between before and after surgery had no significant difference (χ2=1.050, P > 0.05). ④ No death and no hepatic encephalopathy occurred, no thrombosis of splenic vein or portal vein was observed on day 7 after surgery. Conclusionsplenectomy plus pericardial devascularization could decrease portal vein pressure and reduce blood flow of portal vein, while increase blood flow of hepatic artery, it doesn't affect liver function.
Objective To study the influence of the pedicle length on the perforator flaps in hemodynamics. Methods Four mature swine (2 males, 2 females; weight, 23.0±2.0 kg) were applied to the experiment.Two transverse abdominal skin flaps, based on the superior epigastric pedicle orits rectus abdominal muscle perforators, were designed; each swine was used as its own control. At 2 hours and 1, 2, 3 weeks postoperatively, the skin paddle perfusion and the blood stream velocity in the superior epigastric artery were measured by the Laser Doppler Flowmeter and the Color Doppler Ultrasound, respectively. Flap survival percentages were calculated by the grid method at 1 week postoperatively. The swine were euthanatized, and they underwent angiography at 3 weeks postoperatively. Results At 2 hours and 1 week after operation, edema of the perforator flaps with the superior epigastric pedicle was more severe than that of the skin flaps with the rectus abdominal muscle perforator, and the skin perfusion had a statistical difference between the two kindsof flaps (Plt;0.05). The skin paddle viability and the skin perfusion had nostatistical difference after the first week postoperatively (Pgt;0.05). At 2hours and 1 week after operation, the blood stream velocity in the superior epigastric artery in the perforator flap with the superior abdominal artery pediclewas reduced, and there was a statistical difference between the two kinds of flaps (Plt;0.05); however, the velocity was almost the same after the first week postoperatively. Conclusion The excessively long pedicle of the perforator skin flap may have an unfavorable influence on the flap perfusion,especially during the first week after operation, because of the vascular compromise during the dissection of the long pedicle. The blood vessel anastomosis atthis level of the blood vessels may have no relationship with the perforator flap in hemodynamics. This study can also indicate that the ligation of the branches in the recipient vessels cannot make the perforator flaps overperfused.