Involvement of Sympathetic Activity in the Onset of Atrial Fibrillation following Cardiac Surgery / 日本心臓血管外科学会雑誌

Although atrial fibrillation is a complication frequently encountered after cardiac surgery in routine practice, no effective measure is available to prevent its onset, and surgeons often have great difficulties in managing their patients with this condition. On suspicion of the involvement of increased sympathetic activity in the onset, the pre-onset status of 57 patients was examined. The patients were supposedly at low risk of developing atrial fibrillation after cardiac surgery. Additionally, plasma concentrations and 24-hour cumulative urinary excretion of norepinephrine, a biochemical indicator of sympathetic activity, were measured before surgery and on days 3 and 7 of disease. As a result, a group of patients with atrial fibrillation were found to have higher pre-onset heart rates and significantly increased plasma norepinephrine concentrations and 24-hour cumulative urinary norepinephrine excretion compared to controls. Hence, increased sympathetic activity is considered to play a major role in the onset of atrial fibrillation following cardiac surgery.

A Case of Proximal Control of Patent Internal Thoracic Artery Graft Flow by a Supraclavicular Approach during Redo Cardiac Surgery / 日本心臓血管外科学会雑誌

A 68-year-old man who had undergone previous coronary artery bypass grafting was admitted with cardiac failure because of aortic valve stenosis and severe mitral valve regurgitation. Preoperative cardiac catheterization showed a patent left internal thoracic artery (LITA) and a stenotic saphenous vein graft. We performed aortic valve replacement, mitral valve repair, and coronary artery bypass grafting with repeat sternotomy, moderate hypothermia (29.3°C), aortic cross-clamping, retrograde cardioplegia and proximal occlusion of the LITA graft using a soft bulldog clamp. The proximal LITA was occluded through a supraclavicular incision without intrathoracic dissection. Although cardiopulmonary bypass (CPB) time and aortic cross-clamp time were prolonged, the patient was taken off CPB without any problem. The postoperative course was uneventful. We believe that this technique is safe and effective for establishing myocardial protection without deep hypothermia and risk of LITA injury.

Successful Surgical Treatment of Extensive Mitral Annular Calcification Using CUSA and MIRA Valve / 日本心臓血管外科学会雑誌

We experienced a case of extensively calcified mitral annulus and severe mitral regurgitation. A 75-year-old woman underwent successful debridement of an annular calcification with a CUSA^® and replacement of mitral valve with a MIRA^TM valve in a supra-annular position. Use of CUSA^® allowed safe removal of the calcification and prevented the tearing of the A-V groove vessels. In our technique, calcification is left to a certain extent to keep annular strength. Also the MIRA^TM valve has soft and rich sewing cuff, which enhances coaptation in highly calcified annuli and accommodates even fragile tissue. This makes it possible to implant valves even in severely diseased annulus conditions.

A Case of Surgical Treatment of Stanford Type A Closing Aortic Dissection with Variable Morphological Changes / 日本心臓血管外科学会雑誌

A 62-year-old woman presented with acute chest pain. An enchanced CT scan showed type A closing aortic dissection. An ulcer-like projection (ULP) was observed in the abdominal aorta above the superior mesenteric artery on aortography. At 3 months after onset, recurrent chest pain appeared. An enchanced CT scan showed a false lumen in the ascending aorta and a new ULP and localized false lumen were opacified in the distal ascending aorta on aortography. The graft replacement of the ascending aorta was performed using open distal anastomosis under circulatory arrest and retrograde cerebral perfusion. Two intimal tears were found in the aortic root and distal ascending aorta. The patient recovered without complications. Postoperative CT scan and aortography revealed no residual false lumen.