Traumatic Aortic Dissection (Stanford Type A, DeBakey Type II) Caused by Blunt Chest Trauma / 日本心臓血管外科学会雑誌

We report the case of a 55-year-old man who received a hard blow to his chest from a liquid nitrogen hose that caused traumatic aortic dissection (Stanford type A, DeBakey type II). He did not have any other hemorrhagic injury ; therefore, we decided to perform an emergency surgery. The postoperative course was uneventful, and he was discharged on postoperative day 19. Pathological findings were compatible with traumatic aortic dissection. Blunt thoracic aortic injury is a potentially life-threatening injury ; therefore, it is worth remembering that relatively low-energy blunt trauma can cause aortic injury in patients with severe atherosclerosis. The optimal timing of intervention should be individualized in traumatic aortic injury with consideration of associated injuries.

Post-Irradiation Malignant Pericardial Mesothelioma with Recurrent Bloody Pericardial Effusion : a Case Report / 日本心臓血管外科学会雑誌

We report a case of a 64-year-old woman with a history of radiation therapy for breast cancer 27 years ago who developed malignant pericardial mesothelioma. Since 3 years ago, the recurrent bloody pericardial effusion was getting worse, which caused general edema and nocturnal dyspnea. She had a thickened pericardium and the right ventricular pressure curve showed a dip-and-plateau pattern. We diagnosed constrictive pericarditis and performed a pericardiectomy and waffle procedure on the thickened epicardium without cardiopulmonary bypass. The post-operative histology confirmed malignant pericardial mesothelioma and she died on the 17th postoperative day. Pericardial malignant mesothelioma is a rare disorder but very aggressive. This fatal disease may be considered in a patient with recurrent bloody pericardial effusion who has a history of thoracic radiation therapy.

Evaluation for Left Internal Thoracic Artery Graft by Intravascular Ultrasound / 日本心臓血管外科学会雑誌

Postoperative quantitative evaluation of left internal thoracic artery (LITA) grafts is usually performed by angiography, scintigraphy and Doppler flowire. However it is difficult to observe the characteristics of the intima of the LITA graft. The purpose of this study was to evaluate the characteristics and quantity of plaque of intima of LITA grafts in 6 cases after coronary artery bypass surgery using an intra-vascular ultrasound device (IVUS). There was no stenosis or calcification of LITA grafts on angiography. However we found atherosclerotic plaque in all LITA grafts by IVUS. Characteristics of plaque were eccentric in all cases, and soft, hard and mixed plaque were found. The average minimal lumen diameter of LITA grafts was 2.6±0.2mm. The average lumen area of LITA grafts was 5.4±0.7mm². The rate of plaque area was 37.1±5.9%. The eccentric arteriosclerotic plaques were seen in all cases, contradicting the established theory that LITA do not form arteriosclerosis easily. We suggest that IVUS is an effective follow-up device for evaluating the morphological findings and quantitative evaluation of LITA graft in a timely manner.

A Study of Oral Anticoagulant Therapy at an Early Stage after Cardiac Operation to Determine the Starting Dose of Warfarin Therapy / 日本心臓血管外科学会雑誌

Single administration of warfarin at 0.1mg/kg was carried out at an early stage after cardiac operation, and changes in the blood vitamin K levels, blood coagulation factors and the blood warfarin levels within 24 hours of administration were evaluated to determine an ideal mode of initiating the administration and the initial dose in warfarin therapy at an early postoperative stage. The study group consisted of 30 postoperative cardiac cases, and 20 healthy individuals as controls. The results showed that anticoagulant effects cause close to the therapeutic range within 24 hours of administration of oral warfarin therapy in prothrombin time of the postoperative cases. As regards the blood vitamin K levels, both vitamin K₁ and K₂ levels were more depressed in the subjects than in the control group. Differences in the vitamin K level seemed to play a key role in the difference in anticoagulability between the two groups. It was thus implied that the risk of an abrupt decline in coagulability and a decrease in the level of vitamin K parallels the starting level of warfarin instituted in the wake of a cardiac operation. To conclude, safe and effective warfarin therapy should be started at a 0.1mg/kg dosage level at an early stage after the cardiac operation.