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.

Acute aortic dissection complicated with acute myocardial infarction in a case of 61-year-old woman with an aberrant right coronary artery was successfully treated by emergency operation fore type A acute aortic dissection. However, cardiogenic shock and bradycardia occurred after induction of anesthesia due to right ventricle myocardial ischemia. Cardiopulmonary bypass was established quickly and deep hypothermia was induced. We also perfused the right coronary artery with an external shunt tube to prevent the progression of the right ventricular infarction. The right coronary artery, which originated above the left coronary sinus, was dissected totally. We performed ascending and aortic arch replacement and coronary artery bypass grafting with a saphenous vein graft to the right coronary artery under hypothermic circulatory arrest. She had no major reduction of cardiac function. Although it was a rare combination, aberrant right coronary artery was vulnerable to myocardial ischemia associated with acute type A dissection. The external coronary shunt tube was useful for this type of myocardial ischemia.

In 2005, a 64 year-old man underwent implantation of a sirolimus-eluting stent at another hospital for the treatment of severe stenosis of the right coronary artery (RCA) that caused unstable angina pectoris affecting the inferior cardiac wall. He was subsequently admitted to our hospital because of recurrent angina. Diagnostic coronary angiography, performed in November 2006, revealed 75% stenosis of the left main trunk and 99% stenosis of the left circumflex artery. We planned to perform off-pump coronary artery bypass grafting on May 6, 2007. Ticlopidine and aspirin were discontinued 14 days and 1 day before the operation, respectively. We then started continuous intravenous heparin administration. During the operation, the right internal mammary artery was grafted to the left anterior descending artery, and after rotation of the heart in order to graft to the circumflex artery, hypotension and ST elevation in electrode II occurred. The left internal mammary artery was grafted to the left circumflex artery under the support of intra-aortic balloon pumping, but the ST elevation did not normalize. Therefore, an extracorporeal cardiopulmonary bypass was started. Despite the coronary recanalization, the ST elevation in electrode II did not recover. Because of thrombosis of the drug-eluting stent, an aorto-coronary bypass graft to the RCA was performed with a saphenous vein graft. There was no proximal blood flow at the RCA incision. Therefore, we perfused the RCA via a shunt tube from the cardiopulmonary bypass, and subsequently the ST change normalized. However, ST elevation recurred after the operation. An emergency angiography performed immediately postoperatively revealed a patent saphenous vein graft and drug-eluting stent, and spastic change in the RCA distal from drug-eluting stent. After the initiation of a continuous intravenous drip of nicorandil, hypotension and the ST change recovered. Attention to coronary artery spasm after drug-eluting stent implantation is important.

We encountered a very rare case of a patient with hereditary protein S deficiency who underwent successful coronary artery bypass grafting (CABG). A 38-year-old man was admitted for scheduled coronary artery bypass grafting. Preoperative investigation showed protein S deficiency. He underwent two-vessel CABG surgery with regular cardiopulmonary bypass. After hemostasis, intravenous heparin was started. The dose of warfarin was gradually increased until the INR reached about 2.5. Then heparin was stopped. His postoperative course was uneventful. There was no thromboembolic event. Both grafts were patent.

We describe our surgical experience of localized thoracoabdominal aneurysm in a 60-year-old woman with hypertension and hyperlipidemia. She was admitted for severe nausea associated with uremia. The initial CT scan revealed bilateral hydronephrosis, retroperitoneal fibrosis, inflammatory abdominal aneurysm, and localized thoracoabdominal aneurysm. To resolve the bilateral urinary tract obstruction, bilateral ureteral stents were inserted. After the renal function improved, the thoracoabdominal aneurysm was removed and replaced with an 18-mm woven-Dacron graft under partial cardiopulmonary bypass. The inflammation and fibrosis along the abdominal aorta did not extend to the thoracoabdominal aneurysm. Following the case presentation, we discussed the pathophysiologic aspects of this patient.

Rupture of the posterior wall of the left ventricle is rare but it is one of the fatal complications which can follow mitral valve replacement (MVR). Of 216 MVR patients, including 51 who had double valve replacements, we have had four patients (1.9%) with this complication. The rupture occurred on the table in one patient and about 40 to 90min after entering ICU in the others. All the ruptures were repaired under cardiopulmonary bypass and cardioplegic arrest. The site of rupture was type I in two cases and type II in the other two. Two patients expired. One patient who had been repaired in the operating room died from multiple organ failure after a stormy course of two week's duration, and one who had been repaired in ICU died from uncontrollable hemorrhage. In the remaining two patients, one with a type I and one with a type II rupture, successful treatment in ICU was achieved by suturing an equine pericardial patch to the normal endocardium and mitral ring over the entire area of laceration through endocardial site after removal of the valve prosthesis in the first place, and then wrapping the area of epicardial laceration with another equine patch. In order to reduce mortality in patients with left ventricular rupture, repair from inside of the heart using an equine patch described above was very effective, and the preparation to perform the operation immediately after the onset of rupture in ICU is an important consideration as well.

Two patients with an aorto-iliac arteriovenous fistula as a complication of abdominal aortic aneurysms were presented. Both patients showed pulsating abdominal mass, and swelling of unilateral leg. The fistula was preoperatively diagnosed in one and in another it was suspected intraoperatively by careful palpation of continuous thrill on the aneurysm. Successful surgical management was accomplished in both patients. Awareness of this clinical entities is necessary to manage this rare complication in abdominal aortic aneurysm surgery.