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Background: Mitral valve repair is favored over replacement due to superior outcomes. However, extensive infective endocarditis (IE) often has been considered unreconstructable. We retrospectively analyzed the mid-term outcomes of an individualized repair approach using a lifting annuloplasty strip.Methods: Between December 2007 and March 2014, 27 consecutive patients with acute single mitral valve IE (age 43 ± 16 years, 11 men) underwent lifting mitral annuloplasty (LMA) with a strip (Mitracon® strip, 28 mm in 4, 32 mm in 10, and 34 mm in 13). Blood culture was positive in 70 % (Streptococcus 10, Staphylococcus 4, HACEK 3, Enterococcus 1, Gram negative bacilli 1). One case (4 %) had a previously repaired mitral valve-the repair was redone. Via right thoracotomy (74 %) or median sternotomy (26 %), repair was performed by removal of vegetation and resection of infected tissue, the defect typically then being repaired using a bovine pericardial patch (81 %). Artificial chordae were formed in 5 patients. Nine (33 %) of them had posterior leaflet augmentation (PLA) to get sufficient coaptation height. Clinical and echocardiographic follow-up were performed.Results: Compared with preoperative ones, postoperative echocardiograms revealed decreases of left ventricular (LV) end-diastolic dimensions (57.2 ± 6.3 versus, 45.4 ± 6.2, or 44.8 ± 4.1 mm, all p < 0.01). The LV ejection fraction decreased immediately, but recovered (64.4 ± 9.6 % vs. 54.5 ± 9.8 %, or 65.2 ± 6.1 %, p = 0.002, p = 1.000, respectively). The latest follow-up echocardiograms (median 28 months) universally showed no or minimal regurgitation, with a preserved mitral valve opening area (2.27 ± 0.48 cm(2)). During the clinical follow-up (median, 54 months), one (3.7 %) death was observed (in-hospital, due to biliary sepsis and pneumonia). There was no reoperation or major cardiovascular event. The 5 year survival rate was 96.3 %.Conclusions: The repair technique of LMA and/or PLA in patients with IE achieved good structural and functional outcomes as well as an excellent 5 year survival rate. An individualized repair approach should be recommended in patients with acute phase IE. [ABSTRACT FROM AUTHOR]

Background: With recent advances in post-operative care and surgical methods, the number of cardiovascular re-operations is increasing. We analyzed our institutional experience to evaluate the safety and efficacy of the approach methods for cardiac re-operations. Methods: Between September 2007 and December 2010, we performed 208 cardiac re-operations, defined as surgery which was not performed within a month from the previous operation or during the same hospitalization for the same disease and reviewed retrospectively. According to the surgical approach, we divided patients into two groups: median sternotomy group (S-group, n = 146), and thoracotomy group (T-group, n = 62). Results: There were no differences in sex or mean interval from the first surgery to re-operation between the two groups. Mean cardiopulmonary bypass, adhesion dissection time, bleeding control time, and operation time were significantly shorter in the T-group. The need for transfusion (p = 0.001) during adhesion dissection and the chest tube drainage (p < 0.001) were significantly lower in the T-group. There were 10 operative deaths in the S-group (6.8%) and 5 in the T-group (8.1%) (p = 0.757). Pneumonia was the most common cause of death in both groups. Post-operative bleeding did not result in death and there were no cases of wound infection in the T-group. Conclusions: Two approaches for repeated cardiac surgery were safe and effective in terms of mortality, wound infection, bleeding, operation time, adhesion dissecting time, and bleeding control time. We were able to obtain a good visual field and perform safe surgery by applying the thoracotomy method in selective patients for cardiovascular re-operation. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) is a life-threatening arrhythmia that carries the high risk of thromboembolic complication. Stroke often develops in patients who undergo successful Cox Maze procedure, despite the fact that the procedure has shown a high rate of success in sinus conversion from AF. This study examined the preoperative risk factors predictive of stroke following Cox Maze procedure in patients with mitral valve disease.Methods: 240 patients with the mean age of 57 years underwent Cox-Maze IV procedure with mitral valve repair from November 2007 through December 2010. All patients were available during the follow-up period with the mean duration of 23.6 months. This study excluded those patients who had undergone mitral valve replacement because of maintenance of warfarin medicationResults: Sixteen patients had an ischemic stroke. Of these sixteen patients, six had a transitional ischemic accident while the remaining ten had cerebral infarction. Twelve of sixteen showed sustained sinus rhythm, three showed AF and one had pacing rhythm. Univariate analysis showed that only preoperative stroke history was associated with postoperative stroke (p = 0.03). High CHA(2)DS(2)-VASc score, rheumatic etiology, large left atrium (LA), preoperative or postoperative LA thrombus, age, sex, hypertension, and concomitant surgery were not associated with predictive risks for stroke.Conclusions: In the group of patients who underwent the Cox-Maze procedure with mitral valve repair, having a stroke history was the only preoperative risk factor that could lead to a stroke event after surgery. Accordingly, patients with affliction of ischemic stroke, albeit sustained sinus rhythm, may require prophylactic anticoagulation. [ABSTRACT FROM AUTHOR]

Background: Quadricuspid aortic valve (QAV) is a rare congenital anomaly. We investigate the mid-term results of aortic valve reconstruction by tricuspidization in patients with QAV.Methods: We analyzed the outcome of eight consecutive patients who underwent aortic valve reconstruction surgery (AVRS) with pericardial leaflets with symptomatic quadricuspid aortic valve (QAV) disease between December 2007 and May 2012. AVRS consists of leaflet reconstruction and fixation of the sino-tubular junction in order to maintain coaptation of the new valve.Results: Six males and two females were included; ages ranged from 19 to 63 years (mean age, 51 years). According to Hurwitz and Roberts's classification, three patients had type A, three patients had type B, one patient had type C, and one patient had type E. All patients had significant aortic regurgitation (AR): moderate in three patients, moderate to severe in one patient, and severe in four patients. Concomitant ascending aorta wrapping with an artificial vascular graft was performed in one case. There was no occurrence of mortality during the follow-up period (42.4 ± 18.0 months). No redo-operation was required. The NYHA functional class showed improvement from 2.1 ± 0.2 to 1.1 ± 0.2 (p= 0.008). The latest echocardiograms showed AR absent or trivial in seven patients, and mild in one patient. The aortic valve orifice area index (AVAI) was 1.03 ± 0.49 cm2/m2. Compared with preoperative echocardiograms, the left ventricular (LV) ejection fraction showed improvement from 57.6 ± 17.0 to 63.7 ± 13.2% (p=0.036); the end-diastolic and end-systolic LV dimensions showed a significant decrease, from 63.5 ± 9.6 to 49.5 ± 3.1 mm (p=0.012) and 43.6 ± 11.8 to 32.1 ± 5.4 mm (p=0.012), respectively.Conclusion: In patients with QAV, AVRS with tricuspidization showed satisfactory early and mid-term results. Long-term follow-up will be necessary in order to study the durability of AVRS; however, it can be considered as a potential standard procedure. [ABSTRACT FROM AUTHOR]

Background: Mitral valve repair is favored over replacement due to superior outcomes. However, extensive infective endocarditis (IE) often has been considered unreconstructable. We retrospectively analyzed the mid-term outcomes of an individualized repair approach using a lifting annuloplasty strip., Methods: Between December 2007 and March 2014, 27 consecutive patients with acute single mitral valve IE (age 43 ± 16 years, 11 men) underwent lifting mitral annuloplasty (LMA) with a strip (Mitracon® strip, 28 mm in 4, 32 mm in 10, and 34 mm in 13). Blood culture was positive in 70 % (Streptococcus 10, Staphylococcus 4, HACEK 3, Enterococcus 1, Gram negative bacilli 1). One case (4 %) had a previously repaired mitral valve-the repair was redone. Via right thoracotomy (74 %) or median sternotomy (26 %), repair was performed by removal of vegetation and resection of infected tissue, the defect typically then being repaired using a bovine pericardial patch (81 %). Artificial chordae were formed in 5 patients. Nine (33 %) of them had posterior leaflet augmentation (PLA) to get sufficient coaptation height. Clinical and echocardiographic follow-up were performed., Results: Compared with preoperative ones, postoperative echocardiograms revealed decreases of left ventricular (LV) end-diastolic dimensions (57.2 ± 6.3 versus, 45.4 ± 6.2, or 44.8 ± 4.1 mm, all p < 0.01). The LV ejection fraction decreased immediately, but recovered (64.4 ± 9.6 % vs. 54.5 ± 9.8 %, or 65.2 ± 6.1 %, p = 0.002, p = 1.000, respectively). The latest follow-up echocardiograms (median 28 months) universally showed no or minimal regurgitation, with a preserved mitral valve opening area (2.27 ± 0.48 cm(2)). During the clinical follow-up (median, 54 months), one (3.7 %) death was observed (in-hospital, due to biliary sepsis and pneumonia). There was no reoperation or major cardiovascular event. The 5 year survival rate was 96.3 %., Conclusions: The repair technique of LMA and/or PLA in patients with IE achieved good structural and functional outcomes as well as an excellent 5 year survival rate. An individualized repair approach should be recommended in patients with acute phase IE.

Background: Empty fruit bunch (EFB) has many advantages, including its abundance, the fact that it does not require collection, and its year-round availability as a feedstock for bioethanol production. But before the significant costs incurred in ethanol production from lignocellulosic biomass can be reduced, an efficient sugar fractionation technology has to be developed. To that end, in the present study, an NaOH-catalyzed steam pretreatment process was applied in order to produce ethanol from EFB more efficiently., Results: The EFB pretreatment conditions were optimized by application of certain pretreatment variables such as, the NaOH concentrations in the soaking step and, in the steam step, the temperature and time. The optimal conditions were determined by response surface methodology (RSM) to be 3% NaOH for soaking and 160°C, 11 min 20 sec for steam pretreatment. Under these conditions, the overall glucan recovery and enzymatic digestibility were both high: the glucan and xylan yields were 93% and 78%, respectively, and the enzymatic digestibility was 88.8% for 72 h using 40 FPU/g glucan. After simultaneous saccharification and fermentation (SSF), the maximum ethanol yield and concentration were 0.88 and 29.4 g/l respectively., Conclusions: Delignification (>85%) of EFB was an important factor in enzymatic hydrolysis using CTec2. NaOH-catalyzed steam pretreatment, which can remove lignin efficiently and requires only a short reaction time, was proven to be an effective pretreatment technology for EFB. The ethanol yield obtained by SSF, the key parameter determining the economics of ethanol, was 18% (w/w), equivalent to 88% of the theoretical maximum yield, which is a better result than have been reported in the relevant previous studies.

Background: Use of lignocellulosic biomass has received attention lately because it can be converted into various versatile chemical compounds by biological processes. In this study, a two-step pretreatment with dilute sulfuric acid and aqueous ammonia was performed efficiently on rice straw to obtain fermentable sugar. The soaking in aqueous ammonia process was also optimized by a statistical method., Results: Response surface methodology was employed. The determination coefficient (R(2)) value was found to be 0.9607 and the coefficient of variance was 6.77. The optimal pretreatment conditions were a temperature of 42.75°C, an aqueous ammonia concentration of 20.93%, and a reaction time of 48 h. The optimal enzyme concentration for saccharification was 30 filter paper units. The crystallinity index was approximately 60.23% and the Fourier transform infrared results showed the distinct peaks of glucan. Ethanol production using Saccharomyces cerevisiae K35 was performed to verify whether the glucose saccharified from rice straw was fermentable., Conclusions: The combined pretreatment using dilute sulfuric acid and aqueous ammonia on rice straw efficiently yielded fermentable sugar and achieved almost the same crystallinity index as that of α-cellulose.