Objective To investigate the long effect of nonpulsatile flow on changes of structure and function in pulmonary microcirculation and to identify the pulmonary reconstruction under this blood perfusion. Methods Canine models with nonpulsatile flow in the right lung was established, and sacrificed 6 months later. Compare endothelial nitric oxide synthase (eNOS) in vascular endothelium, apoptosis in smooth muscle cell with immunohistochemistry by streptavidinbioepidermmultienzyme complex methodes, and observe structural changes in pulmonary arterioles with optical microscope. Results The expression of eNOS in the right nonpulsatile flow perfusing lung was weaker as compared to the left lung (10 846.7±177.8 vs. 13 136.1±189.6;t=2.240, P=0.040), the fas was ber as compared to the left lung(14 254.1±217.1 vs. 11 976.7±195.7; t=2.160, P=0.040). The ratio of wall thichness/vessel diameter in the right lung(13.64%±12.80% vs. 14.96%±13.10%) and wall area/vessel area(46.40%±11.70% vs. 47.80%±12.20%) was lower as compared to the left lung(Plt;0.05). Conclusion Longterm nonpulsatile flow can decrease the expression of eNOS, contract the muscles in capillary net, and increase pulmonary vascular resistance. Moreover it canincrease the arteriole apoptosis, leading to vascular structure remodeling.
Objective To summarize the surgical experience of supracardiac total anomalous pulmonary venous connection(S-TAPVC) and study the surgical technique and outcomes for S -TAPVC. Methods Eightysix patients with S-TAPVC underwent the surgical repair from May 1985 to December 2007. There were 49 males and 37 females. The patients aged from 7 months to 35 years (mean 9.6 years) and weighed from 4.9 kg to 68.0 kg (mean 23.8 kg). The patients were divided into three groups by the approach for the anastomosis. There were 20 patients in groupⅠthrough the right atrium incision, 49 patients in group Ⅱ through the right and left atrium incisions and 17 patients in group Ⅲ through the top of the left atrium incision. The interrupt continuous anastomosis between the common pulmonary venous and the left atrium was used in all patients. The enlarged atrial septal defect(ASD) was repaired with autopericardium. The vertical vein was ligated if the postoperative left atrial pressure was less than 15 mm Hg. But the vertical vein was opened or just partialy ligated if the postoperative left atrial pressure was more than 15 mm Hg. Results There was no early operative death. The postoperative left atrial pressure in three groups were 9.3±3.2 mm Hg, 9.9±2.9 mm Hg and 11.6±3.8 mm Hg, respectively. The cases with open or just partly ligated vertical vein in three groups were 0 case (0%), 7 cases (14.3%) and 2 cases (11.8%), respectively. The cases of arrhythmia in three groups were 5 cases (25.0%), 15 cases (30.6%)and 1 case (5.9%). The severely low cardiac output syndrome occurred in 2 patients and reoperation for bleeding in 2 patients. The morbidity of arrhythmia in group Ⅲ was less than in group Ⅱ(P=0.042). Conclusion The outcome of surgical repair for S -TAPVC is satisfactory. The anastomosis through the top of the left atrium incision has low occurrence of arrhythmia. The anastomosis through the right and left atrium incision is easy to expose and to perform surgery, especial for old children and adult patients.
Objective To investigate the effect of ischemic preconditioning(IPC) on myocardial ischemic reperfusion injury(I/R) of elderly rats. Methods Fiftysix Wistar rats, of which there were 28 aged from 21-23months(elderly rat) and 28 aged from 4-5months(young rat), were used to build isolated heart perfusion Langendorff model. The rats were divided into 7 groups with random number table(8 in each group): adult control group, adult I/R group, adult IPC group, elderly control group, elderly I/R group, elderly IPC group and elderly enhanced IPC group. The control group underwent a 90-min perfusion without any intervention; the I/R group underwent a 30-min equilibration period, then a 30-min ischemia and a 30-min reperfusion; the IPC group underwent a 10-min equilibration period, then a 5-min ischemia for twice and a 5-min reperfusion, after that a 30-min ischemia and [CM(158-3mm]a 30-min reperfusion; the enhanced IPC group underwent a 10-min equilibration period, then a 5-min ischemia for 4-times and a 5-min reperfusion, after that a 30-min ischemia and a 30-min reperfusion. The recovery rates of cardiac output(CO), left ventricular developed pressure (LVDP), the maximum rising and descending rate of left ventricular pressure (±dp/dtmax) after a 30-min reperfusion were compared among groups. The activity of creatine kinase (CK) in coronary outflow, the level of malonyldialdehyde (MDA) and superoxide dismutase (SOD) before ischemia and after a 30min reperfusion were detected. The myocardial infarction areas were compared among groups. Results After a 30min reperfusion, compared with adult I/R group, in adult IPC group CK reduced significantly(89.48±18.72 U/L vs. 115.76±16.72 U/L,q=6.061,Plt;0.01),the level of MDA decreased significantly(9.53±3.44 nmol/ml vs. 16.84±2.29 nmol/ml,q=7.732,Plt;0.01),the level of SOD increased significantly(584.7±122.62 U/ml vs. 429.46±85.24 U/ml,q=4.754,Plt;0.01),the recovery rates of CO,LVDP,+dp/dtmax and -dp/dtmax increased ignificantly(78.69%±9.68% vs. 65.10%±8.63%,83.61%±8.46% vs. 67.23±8.68%,81.68±8.68% vs. 67.89%±6.89%,89.79%±7.78% vs. 66.79%±8.46%,Plt;0.01), the myocardial infarction areas reduced significantly (5.25%±4.33% vs. 14.75%±8.02%,q=7.458,Plt;0.01)。There was no statistical significance between elderly IPC group and elderly I/R group in the above indexes(Pgt;0.05).However, There was statistical significances between elderly enhanced IPC group and I/R group. CK reduced significantly (88.60±28.32 U/L vs. 105.76±9.64 U/L,q=5.620,Plt;0.01),the level of MDA decreased significantly(8.38±3.36 nmol/ml vs. 16.80±3.06 nmol/ml,q=7.500,Plt;0.01),the level of SOD increased significantly(558.87±78.66 U/ml vs. 433.75±86.65 U/ml,q=7.335,Plt;0.01),the recovery rates of CO,LVDP,+dp/dtmax and -dp/dtmax increased significantly (77.99%±10.02% vs. 66.26%±9.78%,85.59%±6.67% vs. 73.90%±6.66%,83.87%±9.98% vs. 68.90%±8.68%,86.01%±766% vs. 70.39%±7.98%,Plt;0.01), the myocardial infarction areas reduced significantly (795%±6.32% vs. 1568%±10.36%,q=8.680, Plt;0.01). 〖WTHZ〗Conclusion The protective effect of IPC on I/R elderly rat hearts has weakened. The enhanced IPC is able to regain the protective effect of IPC on elderly rat hearts.
Abstract: Objective To evaluate the outcome of reconstruction of right ventricular outlet tract (RVOT) with 0.1 mm Gore-Tex monocusp valve for short and middle term. Methods Between June 2002 to July 2006, 48 patients underwent reconstruction of RVOT with Gore-Tex monocusp valve to correct cardiac anomalies, including 33 patients with tetralogy of Fallot (TOF) and pulmonary stenosis, 8 patients with TOF and pulmonary atresia, 3 patients with TOF and absent pulmonary valve, 2 patients with double outlet of right ventricle and pulmonary stenosis, 1 patient with truncus arterious and 1 patient with complete transposition of great artery, ventricular septal defect and pulmonary stenosis. Results There was no operative death. The postoperative blood oxygen saturation was up to 1.00. The ratioes of right ventricular systolic pressure and left ventricular systolic pressure were between 0.22 to 0.65.The gradient between right ventricle and left or right pulmonary artery was less than 10 mmHg. All patients were followed up including echocardiography ranged from 3 to 48 months. There were no late death and complication. Trivial and mild pulmonary insufficiency was detected in 18 patients and valvular motion remained competent in 40 patients. Conclusion The results suggest that the reconstruction of RVOT with Gore-Tex monocusp valve can achieve excellent outcome for short and middle term.
Objective To summarize the experience of surgical correction of complete atrioventricular septal defect associated with tetralogy of Fallot(CAVSD-TOF). Methods Twelve patients aged 6-16(11.1±2.8) years underwent correction of CAVSD-TOF. The atrioventricular septal defect was closed through a right atriotomy and longitudinal right ventriculotomy in each case. The three-patch technique was used for the first 7 cases and two-patch technique for the later 5 cases. The commissure between the superior and inferior bridging leaflets of the left portion of the common atrioventricular valve was closed in each patient. Right ventricular outflow tract obstruction was relieved by a transannular patch. Results There were 4 deaths in the early postoperative period, 3 deaths in the first 7 cases compared to 1 death in the later 5 cases. The causes of death included severe low cardiac output syndrome(3 cases) and perfusion pulmonary edema(1 case). Six survivors were followed up from 3 months to 13.5 years. Heart function (NYHA) was class I or Ⅱ in all cases. Conclusion CAVSD-TOF can be corrected by using the two-patch technique and closure of atrioventricular septal defect through a combined approach through right atriotomy and right ventriculotomy. Routine closure of the commissure of the left portion of the atrioventricular valve achieves a low incidence of regurgitation.
Objective To summary the experience of extracardiac conduit total cavopulmonary connection (TCPC) and study the operative indication, design, method, and therapeutic efficacy. Methods 29 patients of extracardiac conduit TCPC were reviewed:the average age was 10 years. Of them, there were 9 cases of tricuspid atresia, 9 double inlet ventricle with left ventricular type, 3 mitral atresia, 3 corrected transposition of the great arteries with anatomically right ventricular hypoplasia and 5 double outlet of right ventricle with left ventricular hypoplasia. All patients underwent cardiopulmonary bypass, 12 cases with heart arrested, and 17 without heart arrested. In them, 20 cases’ superior vena cava were anastomosed directly to the upper margin of right pulmonary artery, 9 cases deviated to the left side of right pulmonary artery to enlarge the stoma. For the inferior vena cava stoma, 22 cases’ anterior walls of right atrium were partially incised, and sutured to the posterior wall, then anastomosed with Gore-Tex blood vessel prostheses and connected to pulmonary trunk, and the other 7 cases’ bottom of right atrium was totally incised, the proximal was closed, and the distal was anastomosised with Gore-Tex blood vessel prostheses and connected to the lower margin of right pulmonary artery, deviated to the right sidedness. Results 5 died in the first 22 cases, and the next 7 cases all survive. All patients were followed up for 3 months to 10 years with no late death. Of them, 12 cases had low cardiac output syndrome, and 11 cases of chylothorax. Conclusions Compared with other types of Fontan operation, the extracardiac conduit TCPC has better long-term effects in older or grown-up children. Nevertheless, strict operative adoption, reasonable operative design, refined procedures, carefully observation and treatment are the key points of improving therapeutic efficacy.
Objective To report the surgical treatment for double outlet of ventricle with atrioventricular discordance. Methods 11 patients aged from 3 to 25 years underwent surgical treatment for double outlet of ventricle with atrioventricular discordance. 10 of them were double outlet right ventricle and the other one was double outlet left ventricle. The surgical treatment included biventricular repair (n=9) and single ventricular repair (n=2). The biventricular repair was performed by intraventricular patch repair and extracardiac valved conduit or homograft valved conduit. The single ventricular repair included bidirected Glenn operation and total cavopulmonary connect. Results There were two early deaths in biventricular repair and no death in single ventricular repair. The cause of death was severe low cardiac output syndrome. Four survivors in biventricular repair were followed up from 1 to 11.5 years, three of them were in NYHA class Ⅰ or Ⅱ and one in NYHA class Ⅲ. Conclusions Double outlet of ventricle with atrioventricular discordance can be treated by biventricular repair or single ventricular repair according to the development of ventricle and pulmonary arteries. Closure of ventricular septal defect , no obstruction from ventricle to great artery and no harm of conduction system are the keys of conventional management to achieve good results.