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.
ObjectiveTo analyze the recovery rule of atrial contractility (AC) function after Maze Ⅳ procedure of valvular atrial fibrillation (AF).MethodsIn our hospital from March 2016 to April 2018, 103 patients who underwent cryoablation Maze Ⅳ procedure due to mitral valve lesions associated with persistent or long-term persistent AF were enrolled. There were 42 males and 61 females, with an average age of 58.5±9.1 years. Electrocardiogram and echocardiography were followed up at discharge and 1, 3, 6, 12 months after procedure. A multivariate Cox analysis of predictive factors for AC recovery was applied.ResultsAll the 103 patients were followed up for 1 year. The recovery rate of AC increased gradually after operation. It was not until 3 months after procedure that most of the right atrial contractility (RAC) was accompanied by synchronous recovery of the corresponding left atrial contractility (LAC, Kappa coefficient≥0.40, P<0.05). However, the coexistence of sinus rhythm (SR) and bilateral AC was not consistent well until 1 year after operation (Kappa coefficient≥0.40, P<0.05). One year after procedure, the recovery rates of SR and bilateral AC were 86.4% (89/103) and 66.0% (68/103) respectively. By Cox multivariate regression analysis, longer preoperative AF duration (P=0.040), larger preoperative left atrial diameter (LAD, P=0.003), and AC deletion 3 months after surgery (P=0.037) were predictive factors for AF recurrence in the middle and advanced stages (>3 months) after Maze surgery. At the same time, longer preoperative AF duration and larger preoperative LAD were also negative predictors of middle and late recovery of LAC and bilateral AC (All P<0.05). Receiver operating characteristic curve analysis showed that the best critical value of preoperative AF time and preoperative LAD for prediction of AC recovery was 37 months (sensitivity 99.6%, specificity 76.3%) and 60.5 mm (sensitivity 98.5%, specificity 78.9%), respectively.ConclusionThe recovery of AC after Maze procedure is a dynamic improvement process. Early recovery of AC is beneficial to the stable maintenance of SR in the future. Prolonged duration of AF and enlarged LAD have adverse effects on the outcome of Maze Ⅳ procedure.
Objective To analyze early and midterm outcomes and summarize clinical experience of mitral valve repair with artificial chordae for degenerative mitral regurgitation （MR）. Methods Clinical data of 78 patients with degenerative MR who underwent mitral valve repair with Gore-Tex artificial chordae from October 2008 to December 2011 in General Hospita1 of Shenyang Military Command were retrospectively analyzed. There were 47 male patients and 31female patients with their age of 52.7±9.6 years，who all had degenerative MR. Operation techniques included simple GoreTex artificial chordae replacement in 15 patients，artificial chordae replacement plus quadrangular resection of the posterior leaflet in 58 patients，artificial chordae replacement plus quadrangular resection of the posterior leaflet and Sliding technique in 5 patients. One to three （2.15±1.05） Gore-Tex artificial chordae were used for each patient，and annuloplasty ring was used for all the patients. Thirty-nine patients underwent concomitant tricuspid valvuloplasty. Intraoperative transesophagealechocardiography showed none obvious MR in 62 patients，trivial MR in 13 patients and mild MR in 3 patients. All thepatients were followed up after discharge. Echocardiography was used to evaluate heart function and MR degree duringfollow-up. Results There was no in-hospital death in this group. Postoperative complications included sinus bradycardiain 5 patients，supraventricular tachycardia in 8 patients，late cardiac tamponade in 1 patient，and permanent pacemakerimplantation in 1 patient. Seventy patients were followed up for 1-2 years with the follow-up rate of 89.74% （70/78）. Duringfollow-up，1 patient died of cerebral embolism 13 months after discharge，and all the other patients remained alive. There were 60 patients with NYHA classⅠand 9 patients with NYHA classⅡ. Echocardiography at 1 year after dischargeshowed that left atrial diameter，left ventricular end-diastolic diameter，left ventricular end-systolic diameter，and pulmonary artery systolic pressure were significantly smaller or lower than preoperative values （P＜0.05），left ventricular ejection fraction （68.00%±7.00% vs. 55.00%±6.00%） and cardiac output were significantly higher than preoperative values（P＜0.05），and MR degree （ratio of regurgitation beam area and left atrial area） was significantly reduced compared with preoperative MR degree （3.45%±5.56% vs. 39.55%±9.86%，P＜0.05）. No artificial chordae rupture was found. There were47 patients without MR and 22 patients with trivial MR during follow-up. Conclusion Gore-Tex artificial chordae replacement is a safe and effective surgical technique for the treatment of degenerative MR.
Objective Explore the effect of remote ischemic preconditioning (RIPC) on preoperative heart rate variability in patients with heart valves. Methods From January 2022 to July 2022, screening was conducted among 118 patients based on inclusion/exclusion criteria. Fifty-eight patients were excluded, and 60 patients participated in this trial with informed consent and were randomly divided into a RIPC group (n=30) and a control group (n=30). Due to the cancellation of surgery, HRV data was missing. 7 patients in the control group were excluded, and 5 patients in the RIPC group were excluded, 23 patients in the final control group and 25 patients in the RIPC group were included in the analysis. Comparison of relevant indicators of heart rate variability (standard deviation of NN interval (SDNN), standard deviation of mean value of NN interval in every five minutes (SDANN), mean square root of difference between consecutive NN intervals (RMSSD), percentage of adjacent RR interval>50 ms (PNN50), low frequency component (LF), high frequency component (HF) and LF/HF) at 8 hours in the morning on the surgical day between two groups of patients. Results There was no statistical difference in baseline characteristics between the two groups, and there was no significant difference in heart rate variability 24 hours before intervention (P>0.05). After the intervention measures were taken, the comparison of the results of heart rate variability at 8 hours on the day of operation showed that SDNN and SDANN of patients in the RIPC group were higher than those in the control group, with statistical differences (P<0.05). Conclusion RIPC can stabilize the preoperative heart rate variability of patients undergoing cardiac valve surgery.
Objective To evaluate the effect of left atrial enlargement on atrial myocardial fibrosis degree and levels of the angiotensinⅡ (AngⅡ)/Rac GTPase activating protein 1 (Rac1)/signal transducersand activators of transcription 3 (STAT3) signaling pathways expressing in patients with persistent atrial fibrillation and rheumatic heart disease (RHD). Methods From March to December 2011, 30 patients with RHD who underwent prosthetic valve replacement in our hospital were enrolled, including 16 males and 14 females, aged 42-70 (56.9±6.8) years. Twenty RHD patients with persistent atrial fibrillation as a research group and ten RHD patients with sinus rhythm as a control group (group A) underwent transthoracic echocardiography and right atrial appendage (RAA) tissue samples were obtained from these patients during mitral/aortic valve replacement operation. The research group according to left atrial diameter (LAD) was divided into two groups, ten patients in each group: a group B with LAD of 50–65 mm and a group C with LAD of LAD>65 mm. For each sample, histological examination was performed by hematoxylin-eosin and Masson’s trichrome staining. Light-microscopic pictures of atrial tissues samples were stained and tissue fibrosis degree in each group was analyzed. AngⅡ concentration was measured by enzyme linked immunosorbent assay. Rac1 and STAT3 were measured by western blotting. Results LAD was significantly greater in AF patients with RHD than in the control group. Hematoxylin-eosin staining demonstrated highly organized arrangement of atrial muscles in the control group and significant derangement in both group B and group C with reduced cell density and increased cell size. Moreover, Masson’s trichrome staining showed that atrial myocytes were surrounded by large trunks of collagen fibers in both group B and group C, but not in the group A. There was a positive correlation between atrial tissue fibrosis and LAD. AngⅡ content was positively correlated with LAD. Similarly, Rac1 and STAT3 protein levels were found considerably higher in the group C and group B than in the group A with excellent correlation to LAD. Conclusion In patients with RHD complicated with persistent atrial fibrillation, the degree of atrial fibrosis and the expression level of AngⅡ/Rac1/STAT3 signaling pathways significantly increase with the left atrialenlargement.
ObjectiveTo analyze factors affecting the recovery of postoperative left ventricular function in patients with valvular disease combined with heart failure with reduced ejection fraction [HFrEF, left ventricular ejection fraction (LVEF)<40%].MethodsThe clinical data of 98 patients with valvular disease combined with HFrEF who underwent surgeries in our hospital from January 2011 to June 2018 were retrospectively analyzed, including 75 males and 23 females aged 9-78 (55.3±11.9) years.ResultsA total of 15 patients were dead after the operation, including 4 deaths within 3 months and 11 mid-long-term deaths after the operation. Ninety-one patients were followed up for more than 6 months (10 months to 8.6 years). The postoperative cardiac function (NYHA) of 91 patients was classⅠ-Ⅱ, the LVEF of 18 (19.8%) patients increased more than 10%, that of 47 (51.6%) patients maintained at the preoperative level, and that of 26 (28.6%) patients decreased. Postoperative LVEF was more prone to recover in HFrEF patients with sinus rhythm before operation (P=0.038), valvular disease mainly in aortic valve (P=0.026), obvious reduction of left ventricular end diastolic diameter in early postoperative period (P=0.017), and higher systolic pulmonary artery pressure (SPAP) before operation (P=0.018). The risk factors for postoperative LVEF deterioration included large left atrium before operation (P=0.014), smaller left ventricle end systolic diameter before operation (P=0.003), and fast heart rate after operation (P=0.019). ConclusionMitral valve prolapse patients with obviously increased left ventricular diameter should receive operation as soon as possible. HFrEF patients with aortic valve disease should receive operation positively. The operation efficacy is satisfactory in the HFrEF patients with high SPAP.
ObjectiveTo evaluate the safety and efficacy of mitral valve surgery and cryoablation in elderly patients with mitral valve disease and persistent or long-term persistent atrial fibrillation.MethodsFrom May 2014 to July 2018, 144 patients with mitral valve diseases combined with persistent or long-term persistent atrial fibrillation in the Department of Cardiothoracic Surgery, General Hospital of Northern Theater Command were selected. Among them, there were 69 patients in a non-elderly group (<60 years) including 18 males and 51 females aged 52.07±5.56 years, and 75 patients in an elderly group (≥60 years) including 32 males and 43 females aged 65.23±4.29 years. A propensity-score matching (PSM) study was conducted to eliminate confounding factors. Both groups underwent mitral valve surgery and cryoablation at the same time. A 2-year follow-up was conducted after discharge from the hospital, and the perioperative and postoperative efficacy indexes were compared between the two groups.ResultsAfter PSM analysis, there were 56 patients in each group. The sinus rhythm conversion rate of the two groups at each follow-up time point was above 85%, and the cardiac function was graded asⅠorⅡ, which was significantly improved compared with that before the surgery, but there was no statistical difference between the two groups (P>0.05). Among the perioperative indicators of the two groups, the elderly group had more coronary artery bypass graft surgeries and longer postoperative ICU stay time compared with the non-elderly group (P<0.05), and the differences in other indicators were not statistically different (P>0.05).ConclusionThe mitral valve surgery and cryoablation in elderly patients with mitral valve diseases combined with persistent or long-term persistent atrial fibrillation are safe, and the short-term outcome is satisfactory.
ObjectiveTo study the relationship between preoperative heart rate variability (HRV) and postoperative atrial fibrillation (POAF) after off-pump coronary artery bypass grafting (OPCAB). MethodsA retrospective analysis was performed on the clinical data of 290 patients who were admitted to the Department of Cardiovascular Surgery, General Hospital of Northern Theater Command from May to September 2020 and received OPCAB. There were 217 males and 73 females aged 36-80 years. According to the incidence of POAF, the patients were divided into two groups: a non-atrial fibrillation group (208 patients) and an atrial fibrillation group (82 patients). The time domain and frequency domain factors of mean HRV 7 days before operation were calculated: standard deviation of all normal-to-normal intervals (SDNN), root mean square of successive differences, percentage difference between adjacent normal-to-normal intervals that were greater than 50 ms, low frequency power (LF), high frequency power (HF), LF/HF. ResultsThe HRV value of patients without POAF was significantly lower than that of patients with POAF (P<0.05). The median SDNN of the two groups were 78.90 ms and 91.55 ms, respectively. Age (OR=3.630, 95%CI 2.015-6.542, P<0.001), left atrial diameter (OR=1.074, 95%CI 1.000-1.155, P=0.046), and SDNN (OR=1.017, 95%CI 1.002-1.032, P=0.024) were independently associated with the risk of POPAF after OPCAB. Conclusion SDNN may be an independent predictor of POAF after OPCAB.
Objective To compare the mid- and long-term clinical results of mitral valve plasty and mitral valve replacement in the treatment of functional mitral regurgitation (FMR). MethodsPatients with FMR who underwent surgical treatment in the Department of Cardiovascular Surgery of the General Hospital of Northern Theater Command from 2012 to 2021 were collected. The patients who underwent mitral valve arthroplasty were divided into a MVP group, and those who underwent mitral valve replacement into a MVR group. The preoperative clinical data, operative and perioperative data of the two groups were analyzed retrospectively, and the mid- and long-term follow-up results were compared. Results Finally 236 patients were included. There were 100 patients in the MVP group and 136 patients in the MVR group. The total follow-up rate was 100.0%, the longest follow-up was 10 years, and the average follow-up time was 3.60±2.55 years. There were 14 cumulative deaths in the MVP group and 19 in the MVR group. There was no statistical difference in baseline data between the two groups (P＞0.05). There was no statistical difference between the MVP group and the MVR group in the incidence of adverse events such as extracorporeal circulation time, aortic occlusion time, hospital stay time in the ICU, intraoperative blood loss, or hospitalization death (P＞0.05), but the time of mechanical ventilation in the MVP group was significantly shorter than that in the MVR group, and the difference was statistically significant(P=0.022).There were statistical differences in the left atrial diameter, left ventricular end-diastolic inner diameter, left ventricular end-systolic inner diameter and cardiac function grade between the two groups compared with those before surgery (P<0.05). The left ventricular ejection fraction in the postoperative MVP group was statistically higher than that before surgery (P<0.05), but there was no statistical difference in the postoperative MVR group compared with that before surgery (P>0.05). The LAD in the MVP group was reduced compared with the MVR group, and the difference was statistically different (P<0.05). The recurrence mitral regurgitation in MVP group was higher than that in MVR group, and the difference was statistically significant（10% vs.1.5%, P=0.003）. The cumulative survival rate (P=0.605) and mortality from cardiovascular events (P =0.880) were not statistically significant in the two groups by Kalan-Meier survival analysis. Conclusion The safety and medium- and long-term clinical efficacy of MVP in the treatment of FMR patients were better than MVR, and the left atrium and left ventricle diameter are statistically reduced, and cardiac function is statistically improved. However, the surgeon needs to be well aware of the indications for the MVP procedure to reduce the rate of MR recurrence.
ObjectiveTo evaluate the incidence of postoperative atrial fibrillation (POAF) after dexmedetomidine and diazepam in patients undergoing coronary artery bypass grafting (CABG). MethodsA retrospective cohort study was conducted in the patients who underwent CABG in the General Hospital of Northern Theater Command from October 2020 to June 2021. By propensity score-matching method, the incidence of POAF after dexmedetomidine and diazepam application in patients undergoing CABG was evaluated. ResultsFinally 207 patients were collected, including 150 males and 57 females, with an average age of 62.02±8.38 years. Among the 207 patients, 53 were treated with dexmedetomidine and 154 with diazepam before operation. There was a statistical difference in the proportion of hypertension patients and smoking patients between the two groups before matching (P<0.05). According to the 1∶1 propensity score-matching method, there were 53 patients in each of the two groups, with no statistical difference between the two groups after matching. After matching, the incidence of POAF in the dexmedetomidine group was lower than that in the diazepam group [9.43% (5/53) vs. 30.19% (16/53), P=0.007]. There was no death in the two groups during hospitalization, and there was no statistical difference in the main adverse events after operation. The ICU stay (21.28±2.69 h vs. 22.80±2.56 h, P=0.004) and mechanical ventilation time (18.53±2.25 h vs. 19.85±2.01 h, P=0.002) in the dexmedetomidine group were shorter. Regression analysis showed that age, smoking and diabetes were related to the increased incidence of POAF (P<0.05), and preoperative use of dexmedetomidine was associated with a reduced incidence of POAF (P=0.002). ConclusionFor patients undergoing CABG, the incidence of POAF with dexmedetomidine before operation is lower than that with diazepam. Preoperative application of dexmedetomidine is the protective factor for POAF, and old age, smoking and diabetes are the risk factors for POAF.