[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to compare the cases of minimally invasive mitral valve surgery (MICS-mitral) performed using right mini-thoracotomy (RT) with those performed using median sternotomy (MS).
Between 2008 and 2012, 6137 patients underwent isolated mitral valve repair at 210 institutions and were registered in the Japan Adult Cardiovascular Surgery Database. We compared 756 who underwent MICS-mitral via RT to 5381 MS patients and performed a one-to-one matched analysis based on the estimated propensity score.
The in-hospital mortality was similar between both groups (RT vs. MS: 0.5 vs. 1.1 %). Although the incidence of postoperative stroke, renal failure, and prolonged ventilation was similar, the number of patients with mediastinitis was greater in the MS group (RT vs. MS: 0 vs. 0.7 %, p < 0.01). Reexploration for bleeding was more frequent in the RT group (RT vs. MS: 2.9 vs. 1.4 %, p < 0.01). Mortality and morbidity occurred at a higher rate in low-volume institutions. The propensity analysis showed that the operation-related times were significantly longer in the RT group, while the length of hospital stay was shorter. In a propensity analysis of patients <60 years of age, there was no in-hospital mortality.
MICS-mitral via RT was successful without compromising the clinical outcomes. Although the operation time and postoperative bleeding should be improved, an RT approach is safe in appropriately selected patients, especially those <60 years of age or treated in a high-volume center.
Surgery Today 06/2015; DOI:10.1007/s00595-015-1210-7 · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction Bone marrow-derived autologous human mesenchymal stem cells (MSC) are one of the most promising cell sources for cell therapy to treat heart failure. The cell sheet technique has allowed transplantation of a large number of cells and enhanced the efficacy of cell therapy. We hypothesized that the transplantation of MSC sheets may be a feasible, safe, and effective treatment for ischemic cardiomyopathy (ICM). Methods and Results Human MSCs acquired from bone marrow were positive for CD73, CD90, and CD105, and negative for CD11b and CD45 by flow cytometry. Ten MSC sheets were created from a total cell number of 1 × 108 MSCs using temperature-responsive culture dishes. These were successfully transplanted over the infarct myocardium of porcine ICM models induced by placing an ameroid constrictor on LAD without any procedural-related complications (MSC group = 6: sheet transplantation; sham group = 6, oral intake of tacrolimus in both groups). Premature ventricular contractions were rarely detected by Holter ECG in the MSC group in the first week after transplantation. On echocardiography, the cardiac performance of the MSC group was significantly better than that of the sham group at 8 weeks after transplantation. On histological examination 8 weeks after transplantation, LV remodeling was significantly attenuated compared with the sham group (cardiomyocyte size and interstitial fibrosis were measured). Immunohistochemistry of the vWF showed that the vascular density in the infarct-border area was significantly greater in the MSC group than the sham group. Expression of angiogenesis-related factors in the infarct-border area of the MSC group was signiﬁcantly greater than that of the sham group, as measured by real-time PCR. Conclusions Bone marrow derived MSC sheets improved cardiac function and attenuated LV remodeling in ischemic cardiomyopathy without major complications, indicating that this strategy would be applicable in clinical settings.
Tissue Engineering Part A 06/2015; DOI:10.1089/ten.TEA.2014.0036 · 4.64 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Heart failure mainly caused by ischemic or dilated cardiomyopathy is a life-threatening disorder worldwide. The previous work in cardiac surgery has led to many excellent surgical techniques for treating cardiac diseases, and these procedures are now able to prolong the human lifespan. However, surgical treatment for end-stage heart failure has been under-explored, although left ventricular assist device (LVAD) implantation and heart transplantation are options to treat the condition. LVAD can provide powerful circulatory support for end-stage heart failure patients and improve the survival and quality of life after implantation compared with the existing medical counterparts. Moreover, LVADs play a crucial role in the "bridge to transplantation", "bridge to recovery" and recently have served as "destination therapy". The structural and molecular changes that improve the cardiac function after LVAD implantation are called "reverse remodeling", which means that patients who have received a LVAD can be weaned from the LVAD with restoration of their cardiac function. This strategy is a desirable alternative to heart transplantation in terms of both the patient quality of life and due to the organ shortage. The mechanism of this bridge to recovery is interesting, and is different from other treatments for heart failure. Bridge to recovery therapy is one of the options in regenerative therapy which only a surgeon can provide. In this review, we pathophysiologically analyze the reverse remodeling phenomenon induced by LVAD and comment about the clinical evidence with regard to its impact on the bridge to recovery.
Surgery Today 04/2015; DOI:10.1007/s00595-015-1149-8 · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We conducted in vivo examinations of a newly designed stentless mitral valve (SMV), formed by suturing 2 leaflets with the "legs" serving as chorda tendinea, made from bovine pericardium, to a flexible ring.Methods and Results:Seven pigs underwent implantation of the SMV constructed with a 23-mm (n=5) or 25-mm (n=2) Duran ring. Baseline echocardiography examinations were used to evaluate the annular anteroposterior diameter, and distance between the mitral annulus (MA) and papillary muscles (PMs) to determine SMV-leg length. After removing the native valve, the SMV-legs were fixed to the anterior and posterior PMs, followed by fixation of the ring to the native MA. Immediately after surgery, all animals presented none or trivial mitral regurgitation, with mean and peak trans-SMV pressure gradient values of 1.9±0.8 and 6.0±3.1 mmHg, respectively. The mean length of the SMV-leg was 19.4±3.9 mm, which correlated with the distance between anterior and posterior MA-PM (r=0.96 and 0.94, respectively, P<0.01 for both). The discrepancy between the anteroposterior diameter of the ring (outside diameter) and that of the native valve was 1.0±2.9 mm, which correlated with the trans-SMV pressure gradient (r=0.81, P=0.025).
In our preliminary study, the SMV demonstrated excellent diastolic inflow dynamics and closing function in vivo. Preoperative precise assessment of MV configuration may serve as a basis for selection of appropriate ring size and SMV-leg length. (Circ J 2015; 79: 553-559).
[Show abstract][Hide abstract] ABSTRACT: Background:Feasibility and early results of transfemoral aortic valve implantation using the ACURATE neo/TF(TM)self-expanding stent are reported.Methods and Results:The study group of 15 patients (mean age 83.3±6.0) was enrolled with a mean EuroSCORE and STS score of 21.9±11.6% and 7.5±3.1%, respectively. Clinical and echocardiographic evaluations were performed at baseline, discharge, 30 days and 6 months. The primary endpoint was all-cause mortality at 30 days. Transcatheter aortic valve implantation (TAVI) using the ACURATE neo/TF device was successful in 14 patients; 1 patient underwent valve-in-valve implantation because the prosthetic valve embolized during withdrawal of the delivery system. Conversion to surgery, coronary obstruction, peri-operative stroke, and pacemaker implantation did not occur at 30 days. Mean transvalvular gradients at discharge significantly decreased from 44.2±10.5 mmHg (preprocedural) to 7.7±3.1 mmHg (P<0.0001) and effective orifice area significantly increased from 0.77±0.12 to 1.69±0.25 cm(2)(P<0.0001). None or trace paravalvular leak was revealed in 50.0%, and no patient exhibited moderate or higher paravalvular leak. The overall mortality at 30 days and 6 months was 0% and 6.7%, respectively.Conclusions:A new self-expanding TF TAVI device, ACURATE neo/TF, is safe and effective in the treatment of severe aortic stenosis in elderly patients at high risk for surgery.
[Show abstract][Hide abstract] ABSTRACT: Background:Little is known about the impact of tricuspid annuloplasty (TAP) on annular dynamics. We assessed tricuspid annular dynamics using 3-D transesophageal echocardiography (3D-TEE) before and after TAP with different types of prosthetic ring.Methods and Results:3D-TEE of the tricuspid valve was acquired in 30 patients (TAP with rigid ring [RR], n=8; TAP with flexible ring [FR], n=10; control, n=12). Tricuspid annular dimensions (circumference, area, annular height, anteroposterior [AP], septolateral [SL] diameter) were measured throughout the cardiac cycle. All postoperative tricuspid annular dimension parameters were significantly reduced by TAP, while the AP/SL ratio was significantly increased (before, 0.96±0.16; after, 1.03±0.06; P<0.05). The difference in annular area between diastole and systole was significantly smaller in the TAP groups (11.6%) than in the control (27.9%, P<0.05). Annular height in the FR patients was significantly lower than in the RR group, while the postoperative AP/SL ratio was lower in the RR than the FR and control groups. Change in annular area was not seen in RR patients, while it was seen in the FR and control groups.Conclusions:Annulus motion and shape differ according to the type of prosthetic ring used, although tricuspid regurgitation was well controlled by all types of ring utilized. The present results provide important information for selection of an appropriate prosthetic ring for TAP.
[Show abstract][Hide abstract] ABSTRACT: Poor survival outcomes for patients with severe heart failure (HF) and the donor shortage for heart transplantation warrant the development of myocardial regenerative therapy. We performed a multicenter, phase II study to evaluate the safety and efficacy of autologous skeletal myoblast sheets (TCD-51073).Methods and Results:In 3 study sites, we enrolled 7 patients with severe chronic HF due to ischemic heart disease despite maximal therapy, all of whom underwent transplantation of TCD-51073. No serious arrhythmia was reported, and no changes were noted in the frequency of ventricular extrasystole frequency. The primary efficacy endpoint of the change in left ventricular ejection fraction (LVEF) on gated blood-pool scintigraphy at 26 weeks after transplantation showed that 5 subjects were responders (classified as "improved" or "unchanged"). In addition, LVEF on echocardiography improved over time, with a change in LVEF of 7.1±2.8% at 26 weeks posttransplantation. Among the 7 subjects, 6 showed improvement in New York Heart Association functional class by at least 1 class. The 6-min walk distance was 410.1±136.1 m before transplantation and 455.4±103.7 m at 26 weeks after transplantation.
This study demonstrated the feasibility and safety of the transplantation of TCD-51073 in the patients with severe chronic HF due to ischemic heart disease, suggesting that TCD-51073 might maintain or improve cardiac function, symptoms, and physical function. (Circ J 2015; 79: 991-999).
[Show abstract][Hide abstract] ABSTRACT: Severe donor shortage in Japan makes the waiting period for heart transplantation extremely long and the left ventricular assist devices (LVADs) are often used for bridge-to-transplant. We present three cases of infected and exposed DuraHeart(®) LVAD system treated with free flaps. Four free flaps (two latissimus flaps and two anterolateral thigh flaps) were transferred using the right internal thoracic vessels or left deep inferior epigastric vessels as recipients. The potential significance of the continuous low pressure blood flow generated by the LVAD system on microvascular patency has not been previously reported. All flaps survived and worked efficiently to control the infection and cover the devices. Heart transplantation was conducted in the two of three patients. Free flap transfer is an efficient treatment for the patients with infected and exposed implantable LVAD.
[Show abstract][Hide abstract] ABSTRACT: Background:The aim of the present study was to assess the efficacy of a non-invasive method, transient elastography (FibroScan), in measuring liver stiffness (LS), and whether LS can be used as a marker of cardiac - and hence perioperative - status.Methods and Results:Perioperative LS was prospectively measured using a FibroScan in 30 patients (21 male; 42.2±13.3 years old) who underwent left ventricular assist device (LVAD) implantation. LS was checked pre- and postoperatively, then analyzed in regard to perioperative status. Preoperative LS was 13.3±13.0 kPa (normal, <5.5 kPa), and was abnormal in 77% of patients. Four required bilateral VAD. LS in patients with bilateral VAD tended to be higher than in LVAD patients (25.1±22.7 vs. 11.5±10.5 kPa, P=0.051). No patient with LS ≤7.0 kPa required a right VAD. The incidence of major adverse events was lower in patients with LS ≤12.5 kPa (25% vs. 80%, P<0.05). There were also no mortalities among patients with LS ≤12.5 kPa.Conclusions:LS was correlated with preoperative severity in patients with severe heart failure and reflected liver congestion, and may be useful to predict the requirement of right VAD, as well as postoperative complications in patients with LVAD implantation. This novel modality may be a useful non-invasive assessment method for management of severe heart failure.
[Show abstract][Hide abstract] ABSTRACT: Cell-sheet transplantation induces angiogenesis for chronic myocardial infarction (MI), though insuf?cient capillary maturation and paucity of arteriogenesis may limit its therapeutic effects. Omentum has been used clinically to promote revascularization and healing of ischemic tissues. We hypothesized that cell-sheet transplantation covered with an omentum-flap would effectively establish mature blood vessels and improve coronary microcirculation physiology, enhancing the therapeutic effects of cell-sheet therapy. Rats were divided into 4 groups after coronary ligation; skeletal myoblast cell-sheet plus omentum-flap (combined), cell-sheet only, omentum-flap only, and sham operation. At 4 weeks after the treatment, the combined group showed attenuated cardiac hypertrophy and fibrosis, and a greater amount of functionally (CD31(+)/lectin(+)) and structurally (CD31(+)/α-SMA(+)) mature blood vessels, along with myocardial upregulation of relevant genes. Synchrotron-based microangiography revealed that the combined procedure increased vascularization in resistance arterial vessels with better dilatory responses to endothelium-dependent agents. Serial (13)N-ammonia PET showed better global coronary flow reserve in the combined group, mainly attributed by improvement in the basal left ventricle. Consequently, the combined group had sustained improvements in cardiac function parameters and better functional capacity. Cell-sheet transplantation with an omentum-flap better promoted arteriogenesis and improved coronary microcirculation physiology in ischemic myocardium, leading to potent functional recovery in failing heart.Molecular Therapy (2014); doi:10.1038/mt.2014.225.
[Show abstract][Hide abstract] ABSTRACT: More than 250 continuous flow LVADs have been implanted in Japan during the last 3 years, with 1-year survival rates of 90 %. These excellent results cannot be achieved without VAD teams who know the detail of surgical techniques and perioperative management. Preoperative optimization of RV function is essential and intraoperative managements are focused on adequate balance between right and left ventricle to prevent right ventricular (RV) failure. For postoperative RV failure early institution of temporary RV mechanical support improves outcomes. Immediate CT scanning is crucial if LVAD patients complain of new neurological symptoms. When CT reveals cerebral hemorrhage, INR should be reduced as soon as possible. The driveline (DL) exit site remains a significant source of LVAD-related infections, and orientation and immobilization of the DL is important. Although vacuum assisted closure is useful to facilitate drainage and healing in pump pocket as well as DL infections, urgent heart transplantation, bridging to recovery, or pump exchange may become the only options to eradicate LVAD-related infections. Patients with continuous flow LVAD are more prone to developing de novo aortic insufficiency. Although majority of them can be managed medically, some require surgical intervention. The cause of pump thrombosis is multifactorial, including lowered INR and pump speed, and implantation techniques. It is important to exchange pumps in a timely manner either through a median sternotomy or subcostal incision in highly suspected patients indicated by elevated LDH and left-sided heart failure.
General Thoracic and Cardiovascular Surgery 11/2014; 63(1). DOI:10.1007/s11748-014-0480-0
[Show abstract][Hide abstract] ABSTRACT: Myocardial recovery occurs in a small cohort of patients receiving left ventricular assist device (LVAD) support, but identification of candidates for device removal remains challenging. We hypothesized that hemodynamic evaluation using echocardiography and right heart catheter during temporary suspension of LVAD support (LVAD-off test) can assess cardiac recovery to predict successful device removal. To prove this hypothesis, we reviewed 44 patients who underwent LVAD-off test from January 2000 to March 2011 at Osaka University Hospital. Twenty-two of them underwent LVAD explant, 9 showed sustaining recovery (successful explant, SE-group); whereas 13 had a recurrent heart failure (failed explant, FE-group). The other 22 patients remained LVAD dependent (nonrecovery, NR-group). Echocardiography showed significant lower ejection fraction (LVEF) in NR-group than in SE- and FE-group after termination of LVAD support, but there was no difference between SE- and FE-group. On the other hand, elevation in pulmonary capillary wedge pressure (ΔPCWP) was significantly smaller in SE-group than in FE- and NR-groups. The degree of cardiac fibrosis significantly increased in FE- and NR-group during the LVAD support, while it did not increase in SE-group. The degree of cardiac fibrosis at the time of LVAD explantation correlated significantly with PCWP at LVAD halt and ΔPCWP, and it had significant impact on the outcome after LVAD weaning. In conclusion, the data obtained during LVAD-off test using echocardiography and right heart catheter significantly correlated with the degree of cardiac fibrosis at the time of LVAD explantation. LVAD-off test is a useful method to predict the successful LVAD explantation.
[Show abstract][Hide abstract] ABSTRACT: Recent evidence suggests that transcatheter aortic valve replacement (TAVR) is feasible for treating severe aortic valve stenosis (AS) in patients who are considered high risk for elective surgery. However, it is still unclear whether TAVR is a better option than surgical aortic valve replacement for severe AS with acute decompensated heart failure. We report a case of severe AS with acute heart failure, which was treated successfully by urgent TAVR, with cardiopulmonary support.
Surgery Today 10/2014; 45(7). DOI:10.1007/s00595-014-1059-1 · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cell surface glycans vary widely, depending on cell properties. We hypothesized that glycan expression on induced pluripotent stem cells (iPSCs) might change during cardiomyogenic differentiation toward the myocardial phenotype. N-glycans were isolated from iPSCs, iPSC-derived cardiomyocytes (iPSC-CM), and original C57BL/6 mouse myocardium (Heart). Their structures were analyzed by a mapping technique based on HPLC elution times and MALDI-TOF/MS spectra. Sixty-eight different N-glycans were isolated; the structures of 60 of these N-glycans were identified. The quantity of high-mannose type (immature) N-glycans on the iPSCs decreased with cardiomyogenic differentiation, but did not reach the low levels observed in the heart. We observed a similar reduction in neutral N-glycans and an increase in fucosylated or sialyl N-glycans. Some structural differences were detected between iPSC-CM and Heart. No N-glycolyl neuraminic acid (NeuGc) structures were detected in iPSC-CM, whereas the heart contained numerous NeuGc structures, corresponding to the expression of cytidine monophosphate-N-acetylneuraminic acid hydroxylase. Furthermore, several glycans containing Galα1-6 Gal, rarely identified in the other cells, were detected in the iPSC-CM. The expression of N-glycan on murine iPSCs changed toward the myocardial phenotype during cardiomyogenic differentiation, leaving the structural differences of NeuGc content or Galα1-6 Gal structures. Further studies will be warranted to reveal the meaning of the difference of N-glycans between the iPSC-CM and the myocardium.
PLoS ONE 10/2014; 9(10):e111064. DOI:10.1371/journal.pone.0111064 · 3.23 Impact Factor