Risk of injury to the femoral blood vessels based on the extent of acetabular dysplasia in total hip arthroplasty Abstract We evaluated the course of the femoral blood vessels of patients with acetabular dysplasia. Patients were divided into five groups: those with Crowe type I, II, III, and IV dysplastic hips and those with normal hips. A computed tomography-based hip navigation software was used to measure the distance between the femoral blood vessels and the anterior pelvic wall in four axial planes located 10–40 mm proximal to the pelvic teardrop. In Crowe Groups I through IV, the distance was shortest at a point 20 mm proximal to the pelvic teardrop. Furthermore, the distance decreased as the Crowe classification grade increased. Because the femoral blood vessels pass close to the pelvis in many patients in Crowe III and IV hips, caution is required during surgery in these patients.

Infective endocarditis of bovine pericardial patch in the aortic position in a patient with left ventricular assist device Abstract A 53-year old woman, who had a history of left ventricular assist device implantation for acromegalic cardiomyopathy and aortic valve closure with bovine pericardial patch, was diagnosed with active endocarditis of aortic valve closure patch. The investigation revealed that infection was limited to the aortic valve closure patch; thus, redo aortic valve closure with a new bovine pericardial patch was performed. The postoperative course was uneventful and the infection was sufficiently controlled. Early surgical intervention is mandatory for a good result without spread of infection to the left ventricular assist device pump and formation of embolism.

Jarvik 2000 axial flow ventricular assist device in right single ventricle after Fontan operation Abstract We present a case of successful ventricular assist device support in a 13-year-old female diagnosed with right single ventricle, asplenia, dextrocardia, who had undergone a Fontan operation at 4 years old in an associated children hospital. She underwent placement of Jarvik 2000 axial flow ventricular assist device to the morphologic right ventricle which worked as systemic ventricle. The postoperative course was not eventful. She was waiting for heart transplantation attending high school 3 years after implantation.

A case of Takotsubo cardiomyopathy with cardiogenic shock after influenza infection successfully recovered by IMPELLA support Abstract We recently experienced a case of cardiogenic shock due to influenza-related Takotsubo cardiomyopathy with atrial tachycardia and respiratory distress syndrome. Temporary mechanical circulatory support by IMPELLA 2.5 improved end-organ failure and resulted in cardiac recovery with sinus rhythm conversion.

Interventricular dyssynchrony during continuous-flow left ventricular assist device support: observation using the conductance method Abstract The purpose of this study was to observe and clarify the interventricular dysscynchrony caused by continuous-flow left ventricular assist device (CF-LVAD) support using the conductance method. During CF-LVAD support, the systolic phase of the left ventricle (LV) becomes shorter than that of the right ventricle (RV). Accordingly, timing of the systole and diastole during the cardiac cycle is not synchronous between the LV and RV. In this study, we evaluated this phenomenon in a normal heart model using the adult goat (n = 5, body weight 44.5 ± 2.9 kg). A centrifugal LVAD was implanted under general anesthesia. We inserted the conductance catheter into the RV and LV to obtain the pressure–volume relationship of the two ventricles simultaneously. We defined the dyssynchronous status as the sign (plus or minus) of the LV volume-change opposite to that of RV volume-change. Dyssynchronous phase of the cardiac cycle was observed in 5.6 ± 0.65% of hearts under LVAD pump-off and 25.3 ± 3.3% under LVAD full bypass, respectively (p < 0.05). To the best of our knowledge, this is the first experimental report clarifying interventricular dyssynchrony during CF-LVAD support using the conductance method. Quantification of this phenomenon under various support conditions and assessment of influences on the right ventricular function will be studied in future studies.

Regional citrate anticoagulation and influence of recirculation on ionized calcium levels in the circuit Abstract Regional citrate anticoagulation is now widely used during continuous renal replacement therapy (CRRT), and especially in patients at risk for hemorrhagic complications. A close monitoring is required to avoid citrate overload, leading to metabolic alkalosis or citrate intoxication causing metabolic acidosis. This case report describes a dysfunction of the regional citrate anticoagulation due to the development of a deep vein thrombosis close to the site of insertion of the venous CRRT catheter. The result was a local recirculation in the circuit with a local citrate overload (acidosis and non-measurable calcium). In the patient’s blood samples, the [calciumtotal/Ca2+systemic] ratio remained normal as a proof of local citrate accumulation without systemic effects. Initially, CRRT remained effective, but due to the progressive decrease of serum creatinine and cystatin C clearance, the site of catheter insertion was changed.

Quantification of interventricular dyssynchrony during continuous-flow left ventricular assist device support Abstract Under continuous-flow left ventricular assist device (CF-LVAD) support, the ventricular volume change and cardiac cycle between the left ventricle (LV) and right ventricle (RV) become dyssynchronous due to the shortening of the LV systole. The purpose of this study was to quantify interventricular dyssynchrony based on different CF-LVAD support conditions and assess its relationship with LV unloading. In this study, we evaluated seven goats (body weight 44.5 ± 6.5 kg) with normal hearts. A centrifugal LVAD was implanted under general anesthesia. We inserted the conductance catheters into the left ventricle (LV) and right ventricle (RV) to assess the volume signal simultaneously. We defined the interventricular dyssynchrony as a signal (increase or decrease) of LV volume (LVV) change opposite to that of RV volume (RVV) (i.e., (dLVV/dt) × (dRVV/dt) < 0). The duration of interventricular dyssynchrony (DYS) was reported as the percentage of time that a heart was in a dyssynchronous state within a cardiac cycle. The mean DYS of normal hearts, hearts with LVAD clamp and hearts supported by LVADs with a bypass rate of 50%, 75% and 100% were 5.6 ± 1.6%, 8.7 ± 2.4%, 8.6 ± 2.8%, 15.1 ± 5.1%, and 25.6 ± 8.0%, respectively. Furthermore, the DYS was found to be associated with the degree of LV stroke volume reduction caused by LV unloading. These findings may be useful for understanding interventricular interactions and physiology during CF-LVAD support. Influences on the right ventricular function and heart failure models warrant further study.

Angiogenesis and new bone formation in novel unidirectional porous beta-tricalcium phosphate: a histological study Abstract Affinos® (Kuraray Co., Ltd., Tokyo, Japan) is a beta-tricalcium phosphate (TCP) artificial bone comprising a novel unidirectional porous structure with 57% porosity. This study examined angiogenesis and bone formation over time with unidirectional porous beta-TCP (UDPTCP). Ten Japanese White rabbits were used in this study. A 5 × 8-mm rectangular area of periosteum was resected, followed by preparation of a cortical bone defect using a high-speed bur. UDPTCP was embedded in the defect in the direction of the pores, parallel to the axis of the tibia. Tissue samples were harvested at 2 weeks (n = 3) and 6 weeks (n = 7) after implantation. Just before euthanasia, the vasculature of the lower limb was perfused with saline from the femoral artery and filled with MICROFIL® (Flow Tech, Inc., Carver, MA) to create a vascular cast. The tibia was cut longitudinally at the center of the material. Decalcified sagittal sections treated with hematoxylin and eosin staining, undecalcified sagittal sections treated with Villanueva-Goldner staining, and axial unstained sections were used for histological evaluation. The lengths of the largest vessels and newly formed bone at the material border were measured in a sagittal section. Both lengths were significantly larger at 6 weeks than at 2 weeks. In the axial sections at 2 weeks, newly formed vessels filled with blue dye grew along the pores of the UDPTCP. Mature bone tissue with a lamellar structure was observed at 6 weeks. Our histological findings demonstrated that angiogenesis and bone formation occur over time in UDPTCP.

Accuracy and reliability of continuous blood glucose monitoring during pediatric cardiopulmonary bypass Abstract The purpose of this study was to assess the accuracy and reliability of a continuous blood glucose monitoring system (artificial endocrine pancreas; STG-55, Nikkiso, Tokyo, Japan) during pediatric cardiopulmonary bypass surgery. Twenty-five pediatric patients scheduled to undergo cardiovascular surgery with cardiopulmonary bypass (age 4 months to 11 years; body weight 5.6–59.7 kg) were enrolled. The glucose sensor line of the artificial endocrine pancreas was connected to the venous side of the cardiopulmonary bypass circuit and used for continuous blood glucose monitoring. We obtained 192 samples for blood gas assessment from the cardiopulmonary bypass circuit, and i-STAT (Abbott, East Windsor, NJ, USA) was used for conventional blood glucose assessment. The accuracies of continuous glucose measurements (STG-55) and conventional intermittent glucose measurements (i-STAT) during cardiopulmonary bypass were compared by means of Clarke error grid analysis. The results were divided into five zones, A, B, C, D, and E, and 78.6% of paired measurements were in zone A, while 21.4% were in zone B. We confirmed that the results of this continuous blood glucose monitoring system for cardiopulmonary bypass during pediatric cardiovascular surgery were highly reliable. An artificial endocrine pancreas may facilitate the safe use of intensive insulin therapy during pediatric cardiovascular surgery.