[Dynamics Evaluation of Remodeling Operation Using 4-dimentional Computed Tomography].

OBJECTIVES: The extensibility of the aortic root after the remodeling procedure was evaluated using 4-dimentional computed tomography( 4D-CT). PATIENTS AND METHODS: Seventeen patients( 13 males/4 females), mean age 52 years, who had undergone the remodeling procedure in the last 3 years were included. To understand the dynamics of the aortic root after reconstruction, the R-R interval on the electrocardiogram was divided into 10 equal parts, and the percentage change in area of the basal ring/Valsalva sinus/sino-tubular junction (STJ) level was calculated to evaluate the extensibility of the aortic root. For the basal ring, changes in ellipticity and circumference were also compared. RESULTS: Basal ring, Valsalva sinus, and STJ area changes with cardiac cycle were similar to those in the control group. Basal ring showed a regular circle in systole and an oval in diastole, and its circumference was enlarged in systole. CONCLUSIONS: The use of 4D-CT made it possible to evaluate the extensibility of the aortic root after remodeling procedure. In particular, the mobility of the basal ring is large, suggesting that it guarantees the physiological opening and closing of the valve and contributes to its durability.

[Pulmonary Artery Transection in Surgery for Coronary Artery Fistula].

Coronary artery fistula is a rare abnormality in the communication between a coronary artery and any of the cardiac chambers or major vessels. At present, there is no standard surgical treatment and the most appropriate method is selected on a case-by-case basis. We report one case of coronary artery fistulae in which pulmonary artery transection was required around the left main trunk (LMT). A 62-year-old man who had coronary artery fistulae with an aneurysm which increased from 12 mm to 16 mm in a two-year span. The fistula was located adjacent to the LMT. A complete aneurysm excision under cardiopulmonary bypass was performed, which required pulmonary artery transection. No postoperative complications occurred. Postoperative coronary computed tomography scan showed intact coronary arteries and complete aneurysm removal.

[Laparoscopic Total Gastrectomy for Jehovah's Witness Gastric Cancer Patient after Preoperative Blood Augmentation].

An 80-year-old female of Jehovah's Witness with anemia was diagnosed with advanced gastric cancer(cT4aN2M0, stage ⅢA). The first value of Hb at the clinic was 7.5 g/dL that made it difficult to perform total gastrectomy in safe. The treatment of blood augmentation included the administration of intravenous iron and oral intake of vitamins in the earlier period. The number of hemoglobin was not optimized sufficiently in the first 10 days, that necessitated administration of erythropoietin( ESPO® INJECTION: 24,000 unit×2 times). Hb value increased in 11.6 g/dL 34 days after the treatment, that enabled laparoscopic total gastrectomy to be performed. The tumor infiltrated left crus of diaphragm. The patient was discharged in 16th postoperative day with Hb value of 10.1 g/dL without any complications. Pathological findings showed pT4b(crus) N2M0, stage ⅢB. Preoperative blood augmentation benefited the patients with anemia who decline allogenic blood transfusion. Anemia with malignant tumors is associated with not only iron deficiency due to the chronic bleeding but also functional deficiency or iron sequestration due to malignant itself, inflammation and infection. Erythropoiesis along with infusion of iron contributed to the optimization of Hb value that ensure performing total gastrectomy in safe.

Mechanism of Increased Spinal Cord Blood Flow due to Noradrenaline Administration Using Vascular Resistance: An Experimental Study Using a Canine Model.

Background: During thoracoabdominal aortic surgery, the spinal cord is placed under ischemic conditions. Elevation of systemic blood pressure is thus recommended as a method of increasing the blood supply from collateral networks. This study examined the mechanisms by which noradrenaline administration increases spinal cord blood flow (SCBF) by elevating systemic blood pressure. Methods: In beagles (n = 7), the thoracoabdominal aorta and L2-L7 spinal cord segmental arteries (SAs) were exposed and a distal perfusion bypass was created to simulate clinical practice. SCBF was measured by laser flowmetry at the L5 dura mater and spinal cord perfusion pressure (SCPP) was measured inside the clamped aorta. The six pairs of SAs from L2 to L7 were clamped, and mean systemic blood pressure (mSBP), SCBF, and SCPP were measured before and after clamping and after starting continuous infusion of noradrenaline at 0.5 µg/kg/min. Rates of change in systemic vascular resistance (SVR) and spinal cord vascular resistance (SCVR) were calculated from the measured values. Results: With no SA clamping (control), the rate of increase in SCVR was 0.74 times the rate of increase in SVR (y = 0.2 + 0.74x, r = 0.889, r2 = 0.789; P < 0.01). When all six pairs of SAs were clamped, a weak correlation was evident between rate of change in SCVR and rate of change in SVR, and the rate of increase in SCVR was lower than the rate of increase in SVR (y = 0.39 + 0.07x, r = 0.209, r2 = 0.039; P < 0.01). When all six pairs of SAs were clamped in the absence of distal perfusion, a weak correlation was also evident between rate of change in SCVR and rate of change in SVR, and the rate of increase in SCVR was lower than the rate of increase in SVR (y = 0.19 + 0.08x, r = 0.379, r2 = 0.144; P < 0.01). Conclusions: The rate of increase in SCVR induced by noradrenaline administration was lower than the rate of increase in SVR in the control group with no spinal cord SA clamping and in both experimental groups with clamped SAs (with and without distal perfusion), creating an environment conducive to spinal cord flow distribution.

Simultaneous upper and lower body perfusion using hypothermia during thoracoabdominal aortic surgery.

BACKGROUND: In open thoracoabdominal aortic aneurysm (TAAA) repair, we have been performing vascular reconstruction under moderate to deep hypothermia and assisted circulation using simultaneous upper and lower body perfusion. This method is effective for protecting the spinal cord and the brain, heart, and abdominal organs and for avoiding lung damage. METHODS: TAAA repair was performed under hypothermia at 20-28 °C in 18 cases (Crawford type I in 0 cases, type II in 5, type III in 3, type IV in 4, and Safi V in 6) between October 2014 and January 2023. Cardiopulmonary bypass was conducted by combined upper and lower body perfusion, with perfusion both via the femoral artery and either transapically or via the descending aorta or the left brachial artery. RESULTS: The ischemic time for the artery of Adamkiewicz and the main segmental arteries was 40-124 min (75 ± 33 min). No spinal cord ischemic injury or brain or heart complications occurred. One patient with postoperative right renal artery occlusion and one with an infected aneurysm required tracheostomy, but the intubation time for the other 16 was 32 ± 33 h. The duration of postoperative intensive care unit stay was 6.5 ± 6.2 days, the length of hospital stay was 29 ± 15 days, and no in-hospital deaths occurred. CONCLUSIONS: Simultaneous upper and lower body perfusion under moderate to deep hypothermia during thoracoabdominal aortic surgery may avoid not only spinal cord injury, but also cardiac and brain complications.