Hikaru Ishii

Root aneurysm following aortic valve replacement 20 years after an arterial switch operation

Late development of annuloaortic ectasia (AAE) and progression of aortic regurgitation (AR) are widely recognized outcomes following an arterial switch operation (ASO). We treated a 29‐year‐old male with AAE and rapid aortic root expansion, who underwent ASO as a neonate and aortic valve replacement (AVR) as an adult. He was diagnosed as having dextro‐(D‐loop) transposition of the great arteries after birth and underwent ASO at the age of 13 months. At the age of 19 years, AVR was performed for progressive AR. AAE developed after AVR. In patients who have undergone neonatal ASO, AAE may occur following AVR decades later.

Autologous Skeletal Myoblast Sheet Therapy for Porcine Myocardial Infarction Without Increasing Risk of Arrhythmia

Safety concerns of ventricular tachyarrhythmia have arisen from some clinical trials of autologous skeletal myoblast (SkM) injection therapy. This study examined the effect and safety of SkM sheet therapy in a pig model of chronic myocardial infarction. Minipigs underwent LAD occlusion using a balloon catheter for 2 h, followed by reperfusion. After 28 days, 12 SkM sheets were transplanted onto the infarcted myocardium (sheet group n = 8); the same number of cells was also injected into the myocardium (injection group n = 7), and sham operations were performed as a control (sham group n = 7). Implantable ECG loop recorders (ILR) were placed subcutaneously on the left thorax. At 28 days after transplantation, we assessed cardiac function with MDCT, interrogated ILR, and performed programmed ventricular stimulation (PVS), after which organs were harvested for histopathology. To assess the inflammatory and injury response, inflammation factors and high-sensitive CRP and troponin I were measured at 1, 3, 7, and 28 days after transplantation by the cytokine array method and ELISA, respectively. The sheet group showed an improvement in cardiac function compared with both the injection and sham groups (LVEF change: 5.8 ± 2.7%, -1.0 ± 2.6%, and -3.8 ± 1.8% in the sheet, injection, and sham groups, respectively, p < 0.05). VF was not detected in any group using ILR, while VT was detected in one pig from the injection group. VF was induced in 25.0%, 71.4%, and 28.6% of animals in the sheet, injection, and sham groups, respectively. In the injection group, anti-macrophage-positive cells were observed around the injected cells within the myocardium. Transmission electron microscopic images showed differentiated myofilaments, collagen layers, and a characteristic extracellular matrix surrounding the SkMs in the sheet group. Toroponin I and IL-6 levels were higher in the injection group compared with both the sheet and sham groups. SkM sheets transplanted onto infarcted myocardium improved cardiac function over SkM injection without increasing arrhythmogenicity.

Patency of Saphenous Vein Grafts Using the PAS-Port System During Coronary Artery Bypass Surgery

BACKGROUND Several proximal anastomosis devices have been developed to shorten the time required for a proximal anastomosis and to avoid aortic cross-/side-clamping during coronary artery bypass grafting. This study retrospectively examined the patency of saphenous vein grafts (SVGs) using the PAS-Port System (Cardia Inc, Redwood City, CA). METHODS From 2004 to 2014, 451 patients underwent coronary artery bypass graft operations requiring at least 1 proximal anastomosis using a PAS-Port device. A total of 802 PAS-Port devices were used, and 95.0% (762 of 802) were implanted successfully. Among the successfully implanted anastomoses, 76.8% (585 of 762) were evaluated using coronary angiography or multidimensional computed tomography, or both. The evaluations were performed between postoperative days 4 and 3,182 (mean, 319 ± 624 days). The early (1 to 365 days) and the midterm to long-term (more than 366 days) occlusion rates were examined. A complete postoperative clinical course was recorded for 70.7% of the patients. RESULTS Overall, 93.8% (549 of 585) of the device-dependent SVGs were patent. The patency rates of device-dependent SVGs that were 1, 2, 3, 4, 5, 6, 7, and 8 years old were 90.1% ± 1.8%, 87.1% ± 2.3%, 86.1% ± 2.5%, 82.9% ± 3.3%, 80.6% ± 3.9%, 77.2% ± 5.0%, 77.2% ± 5.0%, and 70.2% ± 8.1%, respectively. The longest follow-up period was 3,182 days (8.7 years). The occlusion rate for device-dependent SVGs tended to decrease as the number of patients accumulated. CONCLUSIONS The PAS-Port system provided acceptable SVG patency and clinical outcome for the early and midterm to long-term. There may be a learning curve for the use of PAS-Port device that affects the device-dependent SVG patency.

Observations of retinal vessels during intermittent pressure-augmented retrograde cerebral perfusion in clinical cases

OBJECTIVES Retrograde cerebral perfusion (RCP) has been used as a cerebroprotective method under hypothermic circulatory arrest (HCA) during aortic surgery. As reported in an animal model in 2005, intermittent pressure-augmented-RCP (IPA-RCP) provides more effective cerebral perfusion than RCP. In 2013, the clinical efficacy of IPA-RCP was described in terms of clinical outcomes and regional cerebral oxygen saturation using infrared spectroscopy. However, the state of cerebral microcirculation during IPA-RCP has not been investigated in humans. The aim of the present study was to investigate cerebral microcirculation during IPA-RCP in humans by assessing the retinal vessels. METHODS Between 2013 and 2014, 8 consecutive patients underwent elective total replacement of the aortic arch for true thoracic aortic aneurysms. The IPA-RCP protocol consisted of a continuous venous pressure that was intermittently augmented at 45 mmHg for 30 s and then decreased to 20 mmHg for 120 s after isolated HCA for 300 s. The retinal vessels were assessed via non-invasive direct visualization of the cerebral microcirculation using a fundus camera. Assessments were done before cardiopulmonary bypass, during isolated HCA, and during IPA-RCP at 20 and 45 mmHg. Ratio of the diameter of retinal vessels to that of the optic disc was calculated from the diameters of the retinal arteries, veins and optic disc at each time point and was statistically examined. RESULTS There were no neurological deficits and mortality. When compared with the control group and both IPA-RCP groups, the retinal vessels in the isolated HCA group were collapsed and the peripheral retinal vessels could not be clearly observed. The RVR was significantly larger in the control group and in both IPA-RCP groups when compared with the isolated HCA group. The RVR of the control group was similar to that of both IPA-RCP groups with regard to the retinal arteries and veins. The RVR of IPA-RCP at 45 mmHg was significantly larger than that at 20 mmHg with regard to the retinal veins. CONCLUSIONS Our study suggested that intermittently augmented venous pressure at 45 mmHg opened the cerebrovenous vessels and enabled adequate cerebral perfusion. IPA-RCP may provide more effective cerebral perfusion under HCA in humans.

Pathologic Features of Lone Aortic Mobile Thrombus in the Ascending Aorta

This report describes the case of a 79-year-old man with aortic mobile thrombus in the ascending aorta, followed by a discussion of the pathologic basis of aortic mobile thrombus formation. The patient underwent replacement of the ascending aorta. Macroscopic examination revealed an aortic wall ulcer with cholesterol-rich atherosclerotic plaque under the aortic mobile thrombus. Microscopic examination showed plaque rupture. These findings are very similar to those of plaque rupture in the coronary artery. We speculate that plaque rupture of localized aortic atherosclerosis is one of the causes of aortic mobile thrombus.

Off-pump hemostasis for left ventricular rupture after myocardial infarction with Hydrofit® and Surgicel®

Left ventricular free wall rupture (LVFWR) is a catastrophic complication of myocardial infarction. In these cases, cardiopulmonary bypass (CPB) should be performed for left ventricular repair, but can impact hemodynamic stability. An 87-year-old man presented with acute shock. He was diagnosed with LVFWR after myocardial infarction. We describe a simple, effective, and reproducible technique to achieve hemostasis at the LVFWR site during emergency operation using Hydrofit® and Surgicel® surgical hemostatic agents. We simply placed and manually pressed the Hydrofit® and Surgicel® composite on the bleeding site. This technique provides complete hemostasis without CPB establishment.

Enhanced hemostasis with a sealant consisting of Hydrofit and Surgicel

Bleeding is a serious concern during surgery for acute aortic dissections. We have used Hydrofit and Surgicel together to achieve hemostasis at the graft anastomotic sites during replacement of the ascending aorta and aortic arch. Complete hemostasis was achieved without further need for any additional sutures.