Injectable Cryogels Associate with Adipose-Derived Stem Cells for Cardiac Healing After Acute Myocardial Infarctions.

Treatment of adipose-derived stem cells (ADSCs) provides support for novel methods of conveying baseline cell protein endothelial cells to promote acute myocardial infarction in gelatin sericin (GS) lamin-coated antioxidant systems (GS@L). The ratio of fixity modules, pores, absorption, and inflammation in the range of ka (65 ka), 149 ±39.8 µm, 92.2%, 42 ± 1.38, and 29 ± 1.9 were observed in the synthesized frames for GS. Herein, ADSC-GS@L was prepared, and the relevant substance for the development of cardiac regenerative applications was stable and physically chemical. In vitro assessments of ADSC-GS@L injectable cryogels established the enhanced survival rates of the cell and improved pro- angiogenic factors as well as pro-inflammatory expression, confirming the favorable outcomes of fractional ejections, fibro-areas, and vessel densities with reduced infraction dimensions. The novel ADSC-injecting cryogel method could be useful for successful heart injury therapies during acute myocardial infarction. Additionally, the method could be useful for successful heart injury therapies during coronary heart disease.

Surgical treatment of congenital left ventricular diverticulum.

BACKGROUND: Congenital left ventricular diverticulum (LVD) is a rare cardiac malformation. Its prevalence rate is less than 0.1% of the congenital heart diseases requiring surgery. Some scholars suggest that all LVD should be actively removed to prevent possible risks, including diverticulum rupture, arterial embolism, and malignant arrhythmia. However, others believe that asymptomatic LVD can be followed up without immediate surgery. We reviewed and reported the diagnosis, clinical features, and surgical treatment of four cases of congenital LVD to provide clinical experience and a reference for the treatment of such patients. METHODS: Four patients (aged 3-32 years old) were diagnosed with congenital LVD and received surgical treatment at the Department of Cardiovascular Surgery of PLA General Hospital, Beijing, China from September 2009 to July 2019. All four patients had complete long-term postoperative follow-up data, including echocardiogram, enhanced cardiac computed tomography (CT), and electrocardiogram to monitor changes in left ventricular structure, heart function, and heart rhythm. RESULTS: In the first case, the fibrodiverticulum under the aortic valve squeezed the right ventricular outflow tract and the right main coronary artery; the morphology of the right ventricle and coronary artery returned to normal after surgery. The second patient was complicated with a huge lipoma in the apex of the left ventricle and underwent lipoma resection during LVD resection surgery. The third and fourth cases had muscular diverticula in the left ventricular apexes and received LVD removal surgery. All four patients recovered well after surgery and their left ventricular morphology and cardiac function were normal without adverse complications, such as atrial fibrillation, ventricular arrhythmia, and cerebrovascular accident. CONCLUSIONS: Although the morphology and character of congenital LVD were different in each case, the use of effective diagnostic and follow-up tools, including echocardiogram, enhanced CT, and magnetic resonance imaging (MRI), allowed for successful surgical treatment of the left ventricular diverticula and symptoms or other malformations. We propose that congenital LVD should be actively treated with surgery, especially considering effectiveness and low risk associated with this therapeutic option.

Short-term and mid-term effects of radiofrequency ablation in mitral valve surgery in patients with different left atrial sizes.

BACKGROUND: To evaluate the efficacy of atrial fibrillation radiofrequency ablation (AFRA) in patients with chronic valvular atrial fibrillation (AF) with different left atrial sizes [left atrial diameter (LAD) >45 or ≤45 mm]. METHODS: Between May 2016 and January 2019, 264 patients who underwent cardiac operations with modified bipolar AFRA in the Department of Cardiovascular Surgery, PLA General Hospital, were enrolled. The clinical data of the patients were analysed, and inclusion and exclusion criteria were implemented. A propensity score was given for two groups of different left atrial sizes: group A (75 patients with LAD >45 mm) and group B (75 patients with LAD ≤45 mm). Preoperative general data, operative indicators, postoperative mortality, complications, and sinus rhythm recovery were analysed and compared between the two groups. RESULTS: The rates of sinus rhythm recovery in group A (LAD >45 mm) at 1 week, 6 months, 1 year, and 2 years after surgery were 84.0%, 81.33%, 73.33%, and 69.33%, respectively, compared with 90.67.0%, 88.00%, 86.67%, and 84.00% at 1 week, 6 months, 1 year, and 2 years after surgery, respectively, in group B (LAD ≤45 mm). The difference between the two groups was statistically significant at the two points in time of 1 year, and 2 years (P<0.05). Warfarin anticoagulation, the standard therapy, was applied after surgery. No new cerebrovascular events occurred in either group during short- and medium-term postoperative follow-up. CONCLUSIONS: Mitral valve surgery using improved Cox-Maze IV bipolar radiofrequency ablation was effective in treating chronic long-term persistent valvular AF and had an excellent sinus rhythm recovery rate. However, the larger the LAD, the less likely a patient was to maintain sinus rhythm as time passed after surgery.

Surgery of ascending aorta with complex procedures for aortic dissection through upper mini-sternotomy versus conventional sternotomy.

BACKGROUND: Use of minimally invasive approaches for isolated aortic valve or ascending aorta surgery is increasing. However, total arch replacement or aortic root repair through a minimally invasive incision is rare. This study was performed to report our initial experience with surgery of the ascending aorta with complex procedures through an upper mini-sternotomy approach. METHODS: We retrospectively analyzed 80 patients who underwent ascending aorta replacement combined with complex procedures including hemi-arch, total arch, and aortic root surgeries from September 2010 to May 2018. Using standard propensity score-matching analysis, 36 patients were matched and divided into 2 groups: the upper mini-sternotomy group (n = 18) and the median sternotomy group (n = 18). The preoperative assessment revealed no statistically significant differences between the two groups. RESULTS: Hospital mortality occurred in one patient (2.8%). The mini-sternotomy group showed a longer cross-clamping time (160 ± 38 vs. 135 ± 36 min, p = 0.048) due to higher rate of valve-sparing aortic root replacement and total arch repair. The cardiopulmonary bypass time in mini-sternotomy group was shorter than that of full sternotomy group (209 ± 47 min vs 218 ± 62 min, p = 0.595) but fell short of significance. There was no significant difference in lower body hypothermia circulatory arrest time between the two groups (40 ± 10 min vs 48 ± 20 min, p = 0.139). The upper mini-sternotomy group displayed a shorter ventilation time (22 vs. 45 h, p = 0.014), intensive care unit stay (4.6 ± 2.7 vs. 7.9 ± 3.7 days, p = 0.005), and hospital stay (8.2 ± 3.8 vs. 21.4 ± 11.9 days, p = 0.001). The upper mini-sternotomy group showed a lower postoperative red blood cell transfusion volume (4.6 ± 3.3 vs. 6.7 ± 5.7 units, p = 0.042) and postoperative drainage volume (764 ± 549 vs. 1255 ± 745 ml, p = 0.034). The rates of dialysis for newly occurring renal failure, neurological complications, and re-exploration were similar between the two groups (p = 1.000). CONCLUSION: The upper mini-sternotomy approach is safe and beneficial in ascending aorta surgery with complex procedures for aortic dissection, including total arch replacement and aortic root repair.

Primary Lymphoma of the Heart: A Case Report of Surgical Treatment and Review of the Literature.

BACKGROUND: The incidence of heart tumors is the lowest in all known tumors. Primary cardiac tumors are especially rare, with an incidence of 0.056% according to autopsy reports. The most common type is myxoma, which account for nearly 70%-80% of them. Only 10% of primary cardiac tumors are malignant, approximately 95% of which are sarcomas, whereas the primary cardiac lymphomas (PCLs) are merely 1%. CASE PRESENTATION: The present study reported a case of PCL with bilateral renal involvement. The patient received right atrial tumor excision and cardiac pacemaker implantation because of obstruction of the right ventricular outflow tract and third degree atrioventricular (AV) block. Primary diffuse large B-cell lymphoma (DLBCL) was diagnosed through pathological examination; complete remission (CR) was achieved after timely treatment with chemotherapy and autologous peripheral blood stem cell transplantation. CONCLUSIONS: PCL is a very rare disease with highly malignancy. With nonspecific clinical features, the diagnosis is mainly done by histopathological and immunohistochemical staining. At the moment, the most effective treatment is chemotherapy. Palliative surgery may be necessary to correct hemodynamics when outflow is obstructed. The specific location, size, and proximity of the tumor 1ead to the prognosis. Once the cardiac conduction system was involved, electrocardiography (ECG) showed high AV block.

Iatrogenic Aortic Valve Perforation after Ventricular Septal Defect Repair.

Iatrogenic aortic valve (AV) perforation during non-aortic cardiac operations is a rare complication. The suture-related inadvertent injury to an AV leaflet can produce leaflet perforation with aortic regurgitation after ventricular septal defect repair (VSDR). We report three consecutive patients who had iatrogenic aortic leaflet perforation during VSDR in other hospitals and referred to our hospital for reoperation. In all three cases, the perforated AV leaflets were preserved and repaired by autologous pericardial patch or direct local closure.

[Long-term outcomes of off-pump coronary artery bypass grafting in patients aged over 75 years].

OBJECTIVE: To investigate the long-term outcomes of off-pump coronary artery bypass grafting (OPCAB) in patients aged over 75 years and analyze the risk factors affecting the outcomes of the procedure. METHODS: Clinical data were reviewed for 97 consecutive patients aged 75 years or above receiving OPCAB at our center between November, 2000 and November, 2013. The perioperative data including length of ICU stay, duration of mechanical ventilation, incidence of postoperative complications and mortality rate of the patients were analyzed. The follow-up data of the patients were also analyzed including all-cause mortality rate and major adverse cardiac and cerebral events (MACCE, including myocardial infarction, cerebrovascular event, and repeated revascularization). RESULTS: The perioperative mortality rate was 3.09% (3/97) in these patients. Of the 97 patients analyzed, 91 (93%) were available for follow-up for 29-192 months (with a median of 95.61∓34.07 months). The 10-year survival rate of the patients was 62% with a 10-year MACCE-free survival rate of 47.4%. During the follow-up, 6 (6.8%) patients underwent repeated revascularization procedures, 12 (12.37%) had cerebrovascular accidents and 5 (5.15%) had myocardial infarction. Logistic regression analysis showed that hypertension (OR=1.388, P=0.043) and diabetes (OR=1.692, P=0.017) were independent predictors of MACCE, and incomplete revascularization did not increase the risk of postoperative MACCE. CONCLUSION: OPCAB is safe and effective in elderly patients with good long-term outcomes. Hypertension and diabetes are independent risk factors of MACCE, and adequate control of blood pressure and blood glucose can reduce the incidence of postoperative MACCE. Incomplete revascularization is not detrimental to the long-term outcomes of OPCAB in elderly patients.

Obesity and novel cardiovascular markers in a population without diabetes and cardiovascular disease in China.

OBJECTIVE: To investigate associations of novel cardiovascular markers with obesity in a general population. METHODS: A total of 9361 individuals without diabetes or cardiovascular disease were studied between 2009 and 2012 in China. High-sensitivity cardiac troponin T (hs-cTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), brachial-ankle pulse wave velocity (baPWV), pulse pressure, and central systolic blood pressure (cSBP) were assessed according to body mass index (BMI) levels and different BMI/metabolic syndrome (MetS) combinations. RESULTS: 'Levels of hs-cTnT, baPWV, pulse pressure, and cSBP increased across BMI levels. Obesity was positively associated with these markers in multivariate models (P<0.05 for all). When stratified by MetS, these associations remained significant in the non-MetS group, and compared with normal weight participants, the obese participants had 1.87 (95% confidence interval: 1.48, 2.36), 1.27 (1.02, 1.57), 1.89 (1.39, 2.57), and 2.71 (2.11, 3.47) fold risks for having elevated hs-cTnT, baPWV, pulse pressure, and cSBP, respectively, and had 1.61 (1.26, 2.05), 1.75 (1.27, 2.42), 2.45 (1.46, 4.11), and 3.14 (2.13, 4.62) fold risks for having 1, 2, 3, and 4 elevated cardiovascular markers, respectively; while no relationship was observed between obesity and these novel markers in the MetS group, after multivariate adjustment. These results were unchanged when using a waist-hip ratio, body fat per cent, and visceral adiposity index to redefine obesity. CONCLUSIONS: Obesity was positively associated with novel cardiovascular markers (except NT-proBNP) in participants without MetS rather than in participants with MetS. Obese participants without MetS also had higher odds of having more number of elevated cardiovascular markers.

Long-Term Outcome of Intra-Myocardial Injection of Autologous Bone Marrow Mononuclear Cells Combined with Isolated Coronary Artery Bypass Grafting for Patients with Chronic Ischemic Heart Failure.

OBJECTIVE: This study aimed to investigate whether intra-myocardial injection of autologous bone marrow mononuclear cells (aBMMNCs) into peri-scarred myocardium during coronary artery bypass grafting (CABG) improved the long-term outcome compared with CABG alone. METHODS: From April 2011 to December 2012, 33 patients with chronic ischemic heart failure were randomly assigned to undergo CABG (control group) or CABG combined with intra-myocardial injection of aBMMNCs (treatment group). The primary endpoints of the study were the changes of left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), and left ventricular end-systolic volume (LVESV) from baseline to six-month and two-year follow-up, respectively. The secondary endpoints were the changes of III and IV NYHA classification, 6-minute walk test, B-type natriuretic peptide (BNP) from baseline to follow-up, and major adverse cardiovascular events (MACES) during the follow-up. RESULTS: No patient died and no severe surgical complication occurred perioperatively in either group. The mean number of transplanted aBMMNCs was 98.5 ± 48.3×106 per patient. The follow-up was completed at six months and 24 months postoperatively. No major transplant-related adverse events were detected during the study. The patients in the treatment group had more significant improvement in LVEF than in the control group at six-month follow-up (8.17% versus 4.71%, P = .020), but this benefit was not found at 24-month follow-up (7.44% versus 5.69%, P = .419). There was no significant difference in changes of LVEDV, LVESV, III and IV NYHA classification, 6-minute walk distance, BNP, and MACES between the two groups all through the study. CONCLUSION: Intra-myocardial injection of aBMMNC transplantation on arrested heart during CABG is a safe procedure based on a longer period observation. The patients with chronic ischemic heart failure can benefit from aBMMNCs transplantation in the short-term (6 months) demonstrated by improved global LVEF compared with the control group; however, this additional benefit dimed with time as showed by 24-month clinical and echocardiographic follow-up results.

[Offer early attention and intervention to patients with valvular heart disease].

As a key feature of the updates, early intervention of valvular heart disease is highlighted in the 2014 AHA/ACC guideline for the management of patients with valvular heart disease. This article reviewed the new guideline in regards to the issue of early intervention of diseases such as aortic stenosis, aortic insufficiency, mitral stenosis, mitral insufficiency, tricuspid insufficiency, and infective endocarditis, with discussion on the related topics according to the authors' understanding and practical experience in China. We conclude that valvular heart disease should receive early intervention and attention should also be paid on the progress of disease.

Is long-term warfarin therapy necessary in Chinese patients with atrial fibrillation after bioprosthetic mitral valve replacement and left atrial appendage obliteration?

BACKGROUND: Long-term warfarin therapy has been used to decrease thromboembolic events in patients with atrial fibrillation (AF) following bioprosthetic mitral valve replacement (BMVR) and left atrial appendage obliteration (LAAO). A retrospective study was conducted to investigate the efficacy of long-term warfarin or aspirin therapy in patients with AF after BMVR and LAAO. METHODS: A total of 215 patients with persistent AF were given anticoagulation therapy with warfarin for the first 3 months after BMVR and LAAO, continuing warfarin or aspirin therapy according to the surgeon's preference. A yearly follow-up with patients was performed by telephone or mail for postoperative condition, cerebrovascular, and bleeding events. RESULTS: Seven patients died in the first 3 months after surgery, including 6 patients from heart failure and 1 patient from sudden death. The remaining 208 patients were divided into two groups: warfarin group (n = 84 patients) and aspirin group (n = 124). The patients in the warfarin group were older than those in the aspirin group and had a lower postoperative left ventricular ejection fraction. Other baseline and operative characteristics were similar. The two groups had similar incidence of thromboembolic events (9.5% versus 8.9%, P = .873) and bleeding events（7.1% versus 3.2%, P = .207). Each group had one intracranial hemorrhage. Eleven patients expired within three months after surgery, 4（4.8%) in the warfarin group and 10（8.1%）in the aspirin group (P = .411 by Fisher exact test). Cumulative survival was not significantly different in the two groups by Kaplan-Meier analysis (P = .55, log-rank test). CONCLUSIONS: At the current time in China, long-term warfarin or aspirin therapy may have no significantly different impact on long-term prognosis after 3 months anticoagulation with warfarin in patients with AF undergoing BMVR and LAAO.

Establishment of a chronic left ventricular aneurysm model in rabbit.

OBJECTIVES: To establish a cost-effective and reproducible procedure for induction of chronic left ventricular aneurysm (LVA) in rabbits. METHODS: Acute myocardial infarction (AMI) was induced in 35 rabbits via concomitant ligation of the left anterior descending (LAD) coronary artery and the circumflex (Cx) branch at the middle portion. Development of AMI was confirmed by ST segment elevation and akinesis of the occluded area. Echocardiography, pathological evaluation, and agar intra-chamber casting were utilized to validate the formation of LVA four weeks after the surgery. Left ventricular end systolic pressure (LVESP) and diastolic pressure (LVEDP) were measured before, immediately after and four weeks after ligation. Dimensions of the ventricular chamber, thickness of the interventricular septum (IVS) and the left ventricular posterior wall (LVPW) left ventricular end diastolic volume (LVEDV), systolic volume (LVESV), and ejection fraction (EF) were recorded by echocardiogram. RESULTS: Thirty one (88.6%) rabbits survived myocardial infarction and 26 of them developed aneurysm (83.9%). The mean area of aneurysm was 33.4% ± 2.4% of the left ventricle. LVEF markedly decreased after LVA formation, whereas LVEDV, LVESV and the thickness of IVS as well as the dimension of ventricular chamber from apex to mitral valve annulus significantly increased. LVESP immediately dropped after ligation and recovered to a small extent after LVA formation. LVEDP progressively increased after ligation till LVA formation. Areas in the LV that underwent fibrosis included the apex, anterior wall and lateral wall but not IVS. Agar intra-chamber cast showed that the bulging of LV wall was prominent in the area of aneurysm. CONCLUSIONS: Ligation of LAD and Cx at the middle portion could induce development of LVA at a mean area ratio of 33.4% ± 2.4% which involves the apex, anterior wall and lateral wall of the left ventricle.

[Surgical treatment of aortic paravalvular abscess by infective endocarditis].

OBJECTIVE: To summarize the clinical features, pathology and surgical treatment experiences in the patients with aortic paravalvular abscess by infective endocarditis. METHODS: The study consisted of a retrospective analysis of 29 cases with aortic paravalvular abscess by infective endocarditis underwent surgical treatment between January 2001 and June 2013. Among the 29 patients, 22 were male and 7 were female, and the mean age was (37 ± 16) years (range from 11 to 63 years). The primary cardiac disease was congenital aortic valve malformation in 16 patients. There were 15 patients with a history of severe heart failure. Of 29 cases, 8 abscess cavities, 13 pseudoaneurysms and 6 fistulas were found, and complete aortoventricular discontinuity was present in 5 patients with serious infections. Of them, the abscess was above the annulus in 14 patients and below the annulus in 10 patients, and simultaneously involved the annulus above and below in 5 patients. 19 patients were culture positive either positive preoperative blood cultures or positive cultures of surgical specimens, including 9 patients with Staphylococcus infection. The paravalvular defect was repaired by patch in 19 cases, and by local closure in 10 cases. The valvular annulus was reconstructed simultaneously in 16 patients. Aortic valve replacement was performed in 26 patients, and Bentall procedure in 2 patients, including 23 with prosthetic mechanical valve and 5 with biological valve. RESULTS: Of the total 29 patients, 28 patients were recovered, and 1 patient was died of sepsis. During 3 months to 13 years postoperative follow-up (average 4.5 years), one was died of non-cardiac cause, and no patient had recurrent endocarditis and paravalvular leakage. CONCLUSIONS: Aortic paravalvular abscess by infective endocarditis is not uncommon, prone to heart failure. According to the different pathological manifestations, the appropriate surgical approach and strategy can achieve satisfactory outcomes.

[Emergency coronary artery bypass grafting for acute coronary syndrome: mid-term follow-up results].

OBJECTIVE: To summarize the experience with emergency coronary artery bypass grafting (ECABG) for management of acute coronary syndrome and analyze the mid-term follow-up results. METHODS: Forty-five ECABG surgeries were performed in 34 male and 11 female patients (aged 65.6∓5.8 years) for cardiogenic shock (5 cases), acute heart failure (6 cases) and refractory unstable angina (34 cases). Twenty patients received the operation within one week after acute myocardial infarction (AMI) and 18 were preoperatively supported by intra-aortic balloon pumping (IABP). All patients had triple-vessel disease and 15 had left main stenosis. Ten patients experienced two myocardial infarctions and 6 had chronic renal dysfunction including two requiring hemodialysis. On-pump operations were performed in all cases with a mean CPB time of 104.2∓29.7 min and cross clamping time of 69.0∓21.3 min. Cold blood or HTK cardioplegia was used for myocardial protection. The left internal mammary artery (LIMA) was routinely anastomosed to the left anterior descending artery (LAD), and the great saphenous vein (GSV) to other target vessels. The mean number of grafts was 2.9∓0.6. RESULTS: Forty-one patients were cured and discharged and 4 patients died with an in-hospital mortality of 8.9%, including one associated with cardiac event (2.2%). IABP was weaned off within 28.5∓10.6 h after surgery except for one patient who died of multiple organ and system failure (MOSF). Thirty-eight patients (92.7%) were followed up for a mean of 37.3∓16.7 months, during which 2 patients died with a mid-term survival rate of 94.7%. Thirty-five (92.1%) patients had New York Heart Association (NYHA) class I and II. The freedom from cardiac event was 90.5%. Follow-up echocardiography showed significantly improved left ventricular dimension and ejection fraction in these cases (P<0.05), and graft patency was 95.8% for the LIMA and 90.5% for the GSV. CONCLUSION: Despite a slight increase of the in-hospital mortality, ECABG can improve the mid-term survival, freedom from cardiac event, and cardiac function when the indications and timing for surgery are well controlled with optimal perioperative management.

[The effect of surgical revascularization on different timing after ST-elevation myocardial infarction on patients with ischemic heart disease and left ventricular dysfunction].

OBJECTIVE: To analysis the influence of surgical revascularization on different timing after ST-elevation myocardial infarction (STEMI) on patients with coronary artery disease and left ventricular dysfunction. METHODS: Clinical data of 225 patients admitted from January 2003 to July 2012 with history of STEMI and left ventricular dysfunction (ejection faraction<50%) who underwent isolated coronary artery bypass grafting was retrospectively reviewed. There were 186 male and 39 female patients. According to the timing of surgical revascularization after STEMI, the patients were divided into early revascularization group (ER group, <21 days), mid-term revascularization group (MR group, 21 to 90 days) and late revascularization group (LR group, >90 days). There were 20 male and 9 female patients in ER group with mean age of (63 ± 10) years, 48 male and 16 female in MR group with mean age of (63 ± 8) years, 118 male and 14 female in LR group with mean age of (62 ± 10) years, respectively. Thirty-day post-operative mortality and major complications were determined as the endpoints to evaluate the early results of operation. RESULTS: The 30-day post-operative mortality were 3.4%,0 and 2.3% among three groups respectively and there was no statistic difference between groups (χ(2) = 2.137, P = 0.330).Low cardiac output syndrome mortality were 13.8%, 3.1% and 2.3% among three groups respectively and there was statistic difference between groups (χ(2) = 8.344, P = 0.015). The ejection fractions was significantly improved in all the three groups from 42% ± 6%, 41% ± 6% and 42% ± 6% preoperatively to 46% ± 7%, 45% ± 10% and 45% ± 9% postoperatively (t = -3.378 to -2.339, all P < 0.05). The left ventricular end diastolic dimension were significantly reduced in MR group and LR group from (54 ± 6) mm and (55 ± 6) mm preoperatively to (47 ± 8) mm and (49 ± 9) mm postoperatively (t = 5.634, 5.885; P = 0.000). There was no significant change in ER group pre- and postoperatively ((51 ± 6) mm vs.(49 ± 7) mm, t = 1.524, P = 0.133). CONCLUSIONS: The patients with coronary artery disease and left ventricular dysfunction can benefit from surgical revascularization on different timing after STEMI, presenting as the reverse of left ventricle remodeling and the improvement of left ventricle function. The short-term results are mainly determined by the patients' condition, surgical technique and the level of perioperative management.It is recommended for this patient cohort to accept surgical revascularization three weeks after STEMI.

[Early results of left atrial appendage closure in cerebral ischemic stroke reduction in patients with mitral valve replacement].

OBJECTIVE: To investigate the role of left atrial appendage (LAA) closure for cerebral ischemic stroke prevention following mitral valve replacement. METHODS: Retrospective data on 860 consecutive adult patients undergoing mitral valve replacement between January 2008 and January 2013 were analyzed. There were 414 male and 446 female patients, with a mean age of (53 ± 12) years. The patients were divided into two groups according to whether the left atrial appendage was closed during operation: LAA closure group (n = 521) and non-LAA closure group (n = 339).Early mortality, postoperative cerebral ischemic stroke and the risk factors for cerebral ischemic stroke were assessed. Multivariate analysis was performed using logistic regression analysis. RESULTS: Compared with non-LAA closure group, LAA closure group had higher proportion of female gender, higher percentage of patients with cardiac insufficiency, pulmonary hypertension and left atrial thrombus, higher incidence of mechanical valve implantation and concurrent tricuspid surgery, and larger preoperative diameter of left atrium, but lower proportion of hypertension and patients undergoing coronary artery bypass surgery, and shorter aorta cross clamping time (χ² = 6.807 to 122.576, t = -2.818 and 3.756, all P < 0.05). There were no differences in exploratory thoracotomy for bleeding and in-hospital mortality between the two groups. Postoperative cerebral ischemic stroke occurred in 12 patients (1.4%). The incidence of cerebral ischemic stroke in LAA closure group was significantly lower than in non-LAA closure group (0.6% vs.2.7%, χ² = 6.452, P = 0.011).Logistic regression analysis showed that LAA closure was a significant protective factor for postoperative cerebral ischemic stroke (OR = 0.189, 95% CI: 0.039 to 0.902, P = 0.037) while history of cerebrovascular disease (OR = 4.326, 95% CI:1.074 to 17.418, P = 0.039) and preoperative diameter of left atrium (OR = 1.509, 95% CI: 1.022 to 1.098, P = 0.002) being the independent risk factors for postoperative cerebral ischemic stroke. The subgroup analysis showed that, for atrial fibrillation patients, LAA closure was a strong protective factor (OR = 0.064, 95% CI: 0.006 to 0.705, P = 0.025), but LAA closure was not a significant predictive factor (OR = 1.902, 95% CI: 0.171 to 21.191, P = 0.601) in non-atrial fibrillation patients. CONCLUSION: Concurrent LAA closure during mitral valve replacement is safe and effective to reduce the early postoperative risk of cerebral ischemic stroke in atrial fibrillation patients.

Optically active particles of chiral polymers.

Particles constructed by chiral polymers (defined as PCPs) have emerged as a rapidly expanding research field in recent years because of their potentially wide-ranging applications in asymmetric catalysis, enantioselective crystallization, enantioselective release, amongst many others. The particles show considerable optical activity, due to the chirality of the corresponding polymers from which the particles are derived. This review article presents an overview on PCPs with emphasis on our group's recent achievements in the preparation of PCPs derived from optically active helical polymers and their applications. PCPs can be prepared via emulsion polymerization, precipitation polymerization, and suspension polymerization by starting from monomers. Emulsification of preformed chiral polymers and self-assembly approaches also can lead to PCPs. Chiral polymer-based core/shell particles, hollow particles, and magnetic particles are also covered because of their remarkable properties and significant potential applications.

Noncovalent chiral functionalization of graphene with optically active helical polymers.

Optically active helical substituted (co)polyacetylenes containing pendent pyrene groups are prepared and then noncovalently immobilized on graphene via π-π interactions. The resulting graphene composite is characterized by XRD, FTIR, Raman, circular dichroism, UV-vis absorption, TEM, TGA, and fluorescent spectroscopy techniques. The helical polyacetylene endows graphene with the desired optical activity. Also interestingly, the dispersibility of the functionalized graphene in tetrahydrofuran is remarkably improved due to the presence of the helical polymer chains. The present methodology opens new opportunities and serves as a versatile platform toward preparing novel graphene-based materials.

[Long-term effects of permanent pacemaker implantation on tricuspid valve regurgitation].

OBJECTIVE: To explore the long-term effects of permanent pacemaker implantation (PPI) on tricuspid valve regurgitation (TR) in Chinese patients so as to determine the incidence and related factors, evaluate its effects on heart structure and function and ascertain the exact mechanism of TR after PPI. METHODS: A total of 430 patients undergoing permanent pacemaker replacement at our hospital between January 2000 and June 2011 were recruited. The patients with isolated atrial lead implantation procedures, significant heart valve disease or chronic obstructive pulmonary disease were excluded. The data of 108 patients who had Doppler echocardiograms performed before the first pacemaker implantation procedure and this pacemaker replacement procedure were obtained and retrospectively analyzed. According to the post-implant grade of TR, the patients were divided into two groups: normal tricuspid (n = 79) and abnormal tricuspid (n = 29). Their clinical characteristics and echocardiographic data between two groups were analyzed and compared. RESULTS: The mean follow-up time (from the first pacemaker implantation) was (13 ± 6) years (range: 4 - 34). Among 108 patients with initially normal tricuspid post-implant, 29 patients (26.9%) developed significant TR during the follow-up. In comparison to those in normal tricuspid group, the patients in abnormal tricuspid group had a longer time from the first pacemaker implantation ((16 ± 7) vs (12 ± 5) years, P = 0.003), more transtricuspid leads (1.31 ± 0.66 vs 1.10 ± 0.30, P = 0.026), larger right atrial size ((38 ± 7) vs (35 ± 4) mm, P = 0.028) and higher prevalence of mild TR and mitral valve regurgitation (MR) pre-implantation (TR: 21% vs 4%, P = 0.015, MR: 28% vs 5%, P = 0.003). The size of right atrium, right ventricle and left atrium in abnormal tricuspid group were more than those in normal tricuspid group. The prevalence of significant MR post-implantation in abnormal tricuspid group was higher than that in normal tricuspid group. The ejection fraction in abnormal tricuspid group was lower than that in normal tricuspid group during the follow-up. CONCLUSIONS: Abnormal TR after PPI during a long-term follow-up is quite common. The related factors include the time interval from the first pacemaker implantation, number of transtricuspid lead, right atrial size, mild TR and MR pre-implantation.