Yoshio Ootaki

Wake Forest University, Winston-Salem, North Carolina, United States

Are you Yoshio Ootaki?

Claim your profile

Publications (110)313.9 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The most prominent long-term complication after the Ross procedure is the risk of autograft dilatation, and therefore its application in patients at increased perceived risk of autograft dilatation (those with bicuspid aortic valve disease, aortic insufficiency [AI] with dilated aorta, collagen vascular diseases such as Marfan syndrome) has been discouraged. We reported a modified Ross procedure in 2005 in which the autograft was completely encased in a polyester graft before implantation to prevent further dilatation of the autograft. This case report describes follow-up of a patient with Marfan syndrome who underwent this modified Ross procedure in July 2005.
    No preview · Article · Jun 2014 · The Annals of Thoracic Surgery
  • Ross M. Ungerleider · Michael Walsh · Yoshio Ootaki
    [Show abstract] [Hide abstract]
    ABSTRACT: Although the pulmonary autograft procedure for aortic valve replacement is a commonly utilized option for children, its use is diminishing in adult-aged patients. One commonly cited concern is the tendency for the pulmonary autograft to dilate in the aortic position. This article reviews a technique we have used in 36 patients since October, 2004 that stabilizes the autograft so that it cannot dilate. There have been no operative or late deaths and the autograft has continued to function in 34 patients. Two patients have undergone autograft replacement because of early failure, which we believe was likely related to technical considerations in our early technique (first reported in the 2005 STCVS Pediatric Cardiac Surgery Annual). The technical modifications described in this article have produced a more reliable and reproducible technique and have not resulted in any autograft failures in our experience. One patient with Marfan’s syndrome and a bicuspid aortic valve is symptom- and dilation-free 8 years post op, with no autograft or pulmonary homograft insufficiency, normal activity and a stable aortic root by serial echocardiography. Our results suggest that this technique might be applicable for selected adult patients in whom autograft growth is not necessary and for whom the risk of autograft dilatation would provide a reason to avoid a pulmonary autograft procedure.
    No preview · Article · Apr 2014 · Pediatric Cardiac Surgery Annual of the Seminars in Thoracic and Cardiovascular Surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: We previously reported renal arterial periarteritis after implantation of a continuous-flow left ventricular assist device in calves. The purpose of the present study was to investigate whether the same periarteritis changes occur in the intrapulmonary arteries after implantation of a continuous-flow right ventricular assist device (CFRVAD) in calves and to determine the mechanism of those histologic changes. Methods: Ten calves were implanted with a CFRVAD for 29 ± 7 days, and we compared pulmonary artery samples and hemodynamic data before and after CFRVAD implantation prospectively. Results: After implantation, the pulsatility index (pulmonary arterial pulse pressure/pulmonary arterial mean pressure) significantly decreased (0.88 ± 0.40 before vs 0.51 ± 0.22 after; p < 0.05), with severe periarteritis of the intrapulmonary arteries in all animals. Periarterial pathology included hyperplasia and inflammatory cell infiltration. The number of inflammatory cells positive for the angiotensin II type 1 receptor was significantly higher after implantation (7.8 ± 6.5 pre-CFRVAD vs 313.2 ± 145.2 at autopsy; p < 0.01). Serum angiotensin-converting enzyme activity significantly decreased after implantation from 100% to 49.7 ± 17.7% at week 1 (p = 0.01). Tissue levels of angiotensin-converting enzyme also demonstrated a significant reduction (0.381 ± 0.232 before implantation vs 0.123 ± 0.096 at autopsy; p = 0.043). Conclusions: Periarteritis occurred in the intrapulmonary arteries of calves after CFRVAD implantation. The local renin-angiotensin system (not the angiotensin-converting enzyme pathway) plays an important role in such changes.
    No preview · Article · May 2013 · The Annals of thoracic surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: Pulmonary artery sling is an incomplete vascular ring, the result of the left pulmonary artery arising from the right pulmonary artery and effectively constricting the airway, and it usually presents within the first weeks to months of life. We report a surgical correction of tracheal stenosis for a two-year-old patient associated with pulmonary artery sling and tracheal broncus.
    No preview · Article · Nov 2012
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective: The objective of this study was to describe characteristics and early outcomes across a large multicenter cohort undergoing coarctation or hypoplastic aortic arch repair. Methods: Patients undergoing coarctation or hypoplastic aortic arch repair (2006-2010) as their first cardiovascular operation in the Society of Thoracic Surgeons Congenital Heart Surgery Database were included. Group 1 patients consisted of those with coarctation or hypoplastic aortic arch without ventricular septal defect (coarctation or hypoplastic aortic arch, isolated); group 2, coarctation or hypoplastic aortic arch with ventricular septal defect (coarctation or hypoplastic aortic arch, ventricular septal defect); and group 3, coarctation or hypoplastic aortic arch with other major cardiac diagnoses (coarctation or hypoplastic aortic arch, other). Results: The cohort included 5025 patients (95 centers): group 1, 2705 (54%); group 2, 840 (17%); and group 3, 1480 (29%). Group 1 underwent coarctation or hypoplastic aortic arch repair at an older age than groups 2 and 3 (groups 1, 2, and 3, 75%, 99%, and 88% <1 year old, respectively; P < .0001). The most common operative techniques for coarctation or hypoplastic aortic arch repair (group 1) were end-to-end (33%) or extended end-to-end (56%) anastomosis. Overall mortality was 2.4%, and was 1%, 2.5%, and 4.8% for groups 1, 2, and 3 respectively (P < .0001). Ventricular septal defect management strategies for group 2 patients included ventricular septal defect closure (n = 211, 25%), pulmonary artery band (n = 89, 11%), or no intervention (n = 540, 64%) without significant difference in mortality (4%, 1%, 2%; P = .15). Postoperative complications occurred in 36% of patients overall and were more common in groups 2 and 3. There were no occurrences of spinal cord injury (0/973). Conclusions: In the current era, primary coarctation or hypoplastic aortic arch repair is performed predominantly in neonates and infants. Overall mortality is low, although those with concomitant defects are at risk for higher morbidity and mortality. The risk of spinal cord injury is lower than previously reported.
    No preview · Article · Oct 2012 · The Journal of thoracic and cardiovascular surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: Neonatal aortic thrombosis is a potentially life-threatening condition with significant morbidity and mortality if undiagnosed and untreated. The most common location of arterial thrombosis in neonates is in the abdominal aorta and is associated with umbilical artery catheterisation. There are only a few previous reports of thrombosis in the ascending aorta. We describe a case of ascending aortic thrombosis in a neonate who underwent successful thrombolytic therapy.
    No preview · Article · Oct 2012 · Cardiology in the Young

  • No preview · Article · Oct 2012 · Circulation Cardiovascular Interventions
  • [Show abstract] [Hide abstract]
    ABSTRACT: Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart defect that usually presents before the age of 1 year. Several surgical options exist for the correction of ALCAPA; however, debate continues regarding the optimal repair technique in adult populations. We report the case of successful surgical repair of ALCAPA with a direct aortic implantation technique in a 44-year-old mother of 4 children.
    No preview · Article · Oct 2012 · Heart Surgery Forum
  • Yoshio Ootaki · Ryuichi Kuromaru · Ross M Ungerleider
    [Show abstract] [Hide abstract]
    ABSTRACT: Progressive aortic root dilatation is a common feature after surgical repair of tetralogy of Fallot. This report describes a successful valve-sparing replacement of the aortic root in a patient with significant dilated aortic root and aortic regurgitation after repair of tetralogy of Fallot.
    No preview · Article · Aug 2012
  • Yoshio Ootaki · James Strainic · Ross M Ungerleider
    [Show abstract] [Hide abstract]
    ABSTRACT: Pentalogy of Cantrell is characterised by a combination of severe defects in the middle of the chest including the sternum, diaphragm, heart, and abdominal wall. Mortality rate after cardiac surgery is usually high. We report a successful total correction of the cardiac defects in a case of Pentalogy of Cantrell with a double-outlet right ventricle prior to abdominal wall defect repair.
    No preview · Article · Apr 2011 · Cardiology in the Young
  • Yoshio Ootaki · Mohamed Sulaiman · Ross M Ungerleider

    No preview · Article · Nov 2010 · The Journal of thoracic and cardiovascular surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: The most prominent, long-term complication after the Ross procedure is autograft dilatation that can present within 1 to 2 years after the Ross operation. We describe a modified Ross procedure in which the autograft is completely encased in a Dacron graft (Hemashield; Maquet Cardiovascular, Wayne, NJ) prior to implantation. We have performed 30 modified Ross procedures since October 2004. There has been no mortality, and at follow-up none of the patients showed autograft dilatation. This article describes our current technique, which we believe is consistently reproducible and may be especially applicable to adults who are at risk for autograft dilatation after the Ross procedure.
    No preview · Article · Sep 2010 · The Annals of thoracic surgery
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Zirconia is a ceramic with material properties ideal for journal bearing applications. The purpose of this study was to evaluate the use of zirconium oxide (zirconia) as a blood journal bearing material in the DexAide right ventricular assist device. Zirconia ceramic was used instead of titanium to manufacture the DexAide stator housing without changing the stator geometry or the remaining pump hardware components. Pump hydraulic performance, journal bearing reliability, biocompatibility, and motor efficiency data of the zirconia stator were evaluated in six chronic bovine experiments for 14-91 days and compared with data from chronic experiments using the titanium stator. Pump performance data including average in vivo pump flows and speeds using a zirconia stator showed no statistically significant difference to the average values for 16 prior titanium stator in vivo studies, with the exception of a 19% reduction in power consumption. Indices of hemolysis were comparable for both stator types. Results of coagulation assays and platelet aggregation tests for the zirconia stator implants showed no device-induced increase in platelet activation. Postexplant evaluation of the zirconia journal bearing surfaces showed no biologic deposition in any of the implants. In conclusion, zirconia ceramic can be used as a hemocompatible material to improve motor efficiency while maintaining hydraulic performance in a blood journal bearing application.
    Full-text · Article · Jun 2010 · Artificial Organs
  • [Show abstract] [Hide abstract]
    ABSTRACT: Our aim was to evaluate the potential use of zirconium oxide (zirconia) as a blood journal bearing material in the DexAide right ventricular assist device. The DexAide titanium stator was replaced by a zirconia stator in several blood pump builds, without changing the remaining pump hardware components. In vitro pump performance and efficiency were evaluated at a predetermined pump speed and flow. Motor power consumption decreased by 20%, and DexAide battery life was extended to over 12 h on two fully charged batteries. The zirconia stator was also successfully evaluated in a severe start/stop test pre- and postexposure of the zirconia to accelerated simulated biologic aging. This study's outcomes indicated the advantages of zirconia as an alternate journal bearing material for the DexAide device.
    No preview · Article · Oct 2009 · Artificial Organs
  • Yoshio Ootaki · Minhaz Uddin · Ross M Ungerleider
    [Show abstract] [Hide abstract]
    ABSTRACT: Loeys-Dietz syndrome is a newly recognized constellation that presents with aortic aneurysm or dissection similar to Marfan's syndrome. We describe successful surgical treatment in a 2-year-old with the syndrome in whom we performed a valve-sparing replacement of the aortic root because of significant dilation of the aortic root and the ascending aorta.
    No preview · Article · Oct 2009 · Cardiology in the Young
  • [Show abstract] [Hide abstract]
    ABSTRACT: The DexAide right ventricular assist device (RVAD) has been developed as an implantable RVAD. The purpose of this study was to determine the final design and optimal anatomical placement of the DexAide RVAD when implanted simultaneously with either of two commercially available left ventricular assist devices (LVADs) in patients. A mock-up DexAide RVAD was used to assess configuration with each of two types of commercially available LVADs at the time of LVAD implantation in three human clinical cases. The pump body of the DexAide RVAD was placed either in the preperitoneal space or in the right thoracic cavity. The DexAide RVAD placed into the right thoracic cavity is suitable for use with the Novacor or HeartMate II LVADs. The results of this study will guide the finalization of the inflow cannula and optimal placement of the DexAide RVAD for human clinical trials.
    No preview · Article · Aug 2009 · Artificial Organs
  • [Show abstract] [Hide abstract]
    ABSTRACT: A right ventricular assist device is a treatment option for patients with severe right ventricular failure after left ventricular assist device (LVAD) implantation. Recognition of risk factors for mortality after biventricular assist device (BiVAD) implantation is important for patient selection and optimal outcomes. We reviewed our experiences between 1991 and 2005 in 44 patients who were supported by both an LVAD and a right ventricular assist device. Thirteen patients (30%) survived until heart transplantation, and 31 patients (70%) died while on support. The multivariate analysis shows that post-LVAD extracorporeal membrane oxygenation and worsening renal function are associated with the highest postoperative mortality. The univariate analysis also included previous thoracic surgery and ischemic cardiomyopathy as potential preoperative indicators for poor outcome after BiVAD implants. No differences were observed in the rates for the need of preoperative support with a ventilator, an intra-aortic balloon pump, or extracorporeal membrane oxygenation, or in the rates of postoperative complications between survivors and nonsurvivors. BiVAD implantation remains one of the challenges in treating severe heart failure. Previous cardiac surgery, elevated creatinine, and post-LVAD extracorporeal membrane oxygenation were risk factors for mortality after BiVAD implantation. Dialated Cardiomyopathy on the other hand was associated with a more favorable outcome.
    No preview · Article · Jan 2009 · Journal of cardiac failure
  • [Show abstract] [Hide abstract]
    ABSTRACT: Canine and porcine hearts have been widely used to investigate diagnoses, interventions, and surgical therapies for ischemic heart disease. Dogs and pigs are known to vary with regard to the anatomic distribution of their coronary arteries. However, the mechanisms of these differences and the differing phasic coronary blood flow patterns between the two species are not well characterized. Phasic coronary blood flow patterns and hemodynamic data were analyzed using three flow probes placed around the left anterior descending (LAD), left circumflex (LCX), and right coronary (RCA) arteries in both canine and porcine models. Systolic left ventricular pressure, arterial pressure, and systemic vascular resistance in dogs were higher than in pigs. Likewise, total coronary blood flow, LAD flow, and LCX flow were higher in dogs than in pigs. LCX flow was higher in dogs, but RCA flow was higher in pigs. Diastolic fraction and diastolic/systolic peak velocity ratio of the LAD, LCX, and RCA showed no significant differences at baseline between dogs and pigs. Systolic LAD flow in dogs decreased after the creation of an LAD stenosis, whereas systolic LAD flow in pigs increased. Coronary blood flow patterns in dogs and pigs are quite different. These findings are potentially relevant to understanding the physiology of myocardial blood perfusion in dogs and pigs with ischemic heart disease.
    No preview · Article · Nov 2008 · Medical science monitor: international medical journal of experimental and clinical research
  • Source
    A Manzo · Y Ootaki · C Ootaki · K Kamohara · K Fukamachi
    [Show abstract] [Hide abstract]
    ABSTRACT: Several studies have been performed to assess heart rate variability (HRV) in several species such as humans, dogs, pigs, calves, rabbits and rats. However, haemodynamic parameters are totally different in each animal, and optimal animal models for studying HRV corresponding to human HRV are still unclear. The purpose of this study was to assess HRV in human subjects and to compare those HRV data with canine, bovine and rabbit HRV data. The heart rate in the human subjects (62.8 +/- 7.4 bpm) was significantly lower than that in dogs (124.2 +/- 18.8 bpm, P < 0.001), calves (73.4 +/- 10.5 bpm, P < 0.05), and rabbits (217.3 +/- 21.5 bpm, P < 0.001). The low-frequency waves (LF) (57.9 +/- 65.8 ms(2)/Hz) and high-frequency waves (HF) (33.8 +/- 49.1 ms(2)/Hz) in rabbits were significantly lower than human LF (1216.3 +/- 1220.7 ms(2)/Hz, P < 0.05) and HF (570.9 +/- 581.3 ms(2)/Hz, P < 0.05). Dogs and calves showed similar LF (991.1 +/- 646.1 ms(2)/Hz and 547.0 +/- 256.9 ms(2)/Hz, respectively), HF (702.1 +/- 394.1 ms(2)/Hz and 601.0 +/- 666.6 ms(2)/Hz, respectively) and LF/HF (2.0 +/- 1.3 and 2.5 +/- 1.9, respectively) when compared with the human data. The present study shows that dogs and calves revealed similar HRV values as those which relate to humans. Large deviation of the HRV values in rabbits compared with humans might be considered when conducting animal studies using those animals to reflect human clinical situations.
    Full-text · Article · Nov 2008 · Laboratory Animals
  • [Show abstract] [Hide abstract]
    ABSTRACT: Occlusion of the left atrial appendage is proposed to reduce the risk of stroke in patients with atrial fibrillation. The third-generation atrial exclusion device, modified to provide uniform distribution of pressure at appendage exclusion, was assessed for safety and effectiveness in a canine model and compared with a surgical stapler. The atrial exclusion device consists of 2 parallel, straight, rigid titanium tubes and 2 nitinol springs with a knit-braided polyester fabric. Fourteen mongrel dogs were implanted with the device at the base of the left atrial appendage via a median sternotomy. In each dog, the right atrial appendage was stapled with a commercial apparatus for comparison. The animals were evaluated at 7 days (n = 3), 30 days (n = 5), and 90 days (n = 6) after implantation by epicardial echocardiography, left atrial and coronary angiography, gross pathology, and histology. Left atrial appendage exclusion was complete and achieved without hemodynamic instability, and coronary angiography revealed that the left circumflex artery was patent in all cases. A new endothelial tissue layer developed on the occluded orifice of the left atrium 90 days after implantation. This endothelial layer was not evident on the stapled right atrial appendage. In dogs, the third-generation atrial exclusion device achieved easy, reliable, and safe exclusion of the left atrial appendage with favorable histologic results. Clinical application could provide a new therapeutic option for reducing the risk of stroke in patients with atrial fibrillation.
    No preview · Article · Nov 2008 · The Journal of thoracic and cardiovascular surgery

Publication Stats

1k Citations
313.90 Total Impact Points


  • 2014
    • Wake Forest University
      Winston-Salem, North Carolina, United States
  • 2013
    • Case Western Reserve University
      • Department of Biomedical Engineering
      Cleveland, Ohio, United States
  • 2009-2011
    • Case Western Reserve University School of Medicine
      Cleveland, Ohio, United States
  • 2004-2010
    • Lerner Research Institute
      Cleveland, Ohio, United States
    • Kobe University
      Kōbe, Hyōgo, Japan
  • 2008
    • Cleveland Clinic Laboratories
      Cleveland, Ohio, United States