Keiju Kotoh

Impact of preoperative atrial fibrillation on the late outcome of off-pump coronary artery bypass surgery

OBJECTIVE The impact of pre-existing atrial fibrillation on the long-term outcome in patients after off-pump coronary revascularisation is not well known. This study aims to determine the independent effects of preoperative atrial fibrillation on the early and late outcomes of off-pump coronary artery bypass surgery. METHODS A total of 513 patients undergoing isolated coronary artery bypass surgery using off-pump approach between 2000 and 2005 were studied. Twenty-six of them (5.1%) had preoperative atrial fibrillation (15 had paroxysmal atrial fibrillation and 11 had persistent or permanent atrial fibrillation) and the other 487 patients were in normal sinus rhythm. Early and late outcomes were compared retrospectively between patients with preoperative atrial fibrillation and patients in sinus rhythm. The median follow-up period for the entire study population was 3.3 + or - 2.7 years. RESULTS The baseline characteristics of the patients with preoperative atrial fibrillation were generally similar to those of patients in sinus rhythm. However, the patients with atrial fibrillation had a significantly lower left ventricular ejection fraction compared with those in sinus rhythm (50 + or - 15 vs 56 + or - 12%, p=0.03). The mean age of the atrial fibrillation group was almost 3 years more than that of the sinus rhythm group. Operative mortality was similar in patients with atrial fibrillation (3.8%) and those in sinus rhythm (1.0%). Ten patients developed cerebral infarction within 7 days after surgery, including one patient (3.8%) from the atrial fibrillation group and nine patients (1.8%) from the sinus rhythm group. Long-term survival was significantly decreased in the atrial fibrillation group (5-year survival: 70 + or - 9.6% vs 87 + or - 1.8%; p=0.0018). Freedom from cerebral complications was also significantly decreased in the atrial fibrillation group (5-year survival: 85 + or - 8.3% vs 95 + or - 1.2%; p=0.0009), but there were no differences in cardiac death and major cardiac adverse events. On Cox proportional hazards regression analysis, preoperative atrial fibrillation was a significant adverse predictor for survival (hazard ratio=3.0, 95% confidence intervals (CIs) 1.3-6.9; p=0.009) and independent predictor of late cerebral infarction (hazard ratio=6.2, 95% CIs 2.0-19.3; p=0.0002). CONCLUSIONS Uncorrected preoperative atrial fibrillation is strongly associated with poor long-term survival and increased late cerebral complications after off-pump coronary artery bypass surgery. Concomitant atrial fibrillation surgery should be considered to improve the long-term results of surgical revascularisation.

Ruptured abdominal aortic aneurysm and aortoiliac vein fistula

A 67-year-old man was admitted with severe abdominal pain and back pain. Computed tomography showed an infrarenal abdominal aortic aneurysm (8.4 × 8.3 cm) and a large retroperitoneal hematoma. Immediately afterwards, the patient suffered circulatory collapse and was rushed to the operating theater. A fistula communicating with the left iliac vein was found. It was repaired with a Dacron patch while balloon-tipped catheters controlled the bleeding. The abdominal aortic aneurysm was replaced with a bifurcated graft. The postoperative course was uneventful. There have been few reports of successful repair of a ruptured abdominal aortic aneurysm associated with aortoiliac arteriovenous fistula.

Primary Cardiac Malignant Lymphoma: Survival for 13 Years After Surgical Resection and Adjuvant Chemotherapy

We report a patient who has survived for 13 years after surgical resection of a cardiac malignant lymphoma. A 73-year-old woman underwent partial resection of a tumor occluding the tricuspid valve, which arose from the right atrium. The pathologic diagnosis was diffuse large B cell lymphoma. She was treated with adjuvant chemotherapy for 6 months postoperatively. Since then, she has shown no evidence of recurrence, without any further treatment. To our knowledge, this is the longest surviving case of cardiac malignant lymphoma. The therapeutic strategy for this malignant cardiac tumor is discussed briefly.

On-Pump Beating Heart Extraanatomical Ascending-Descending Aortic Bypass Using a Beating Heart Positioner in an Adult with Aortic Coarctation

The prognosis of uncorrected aortic coarctation is poor due to development of heart failure. We performed an on-pump beating heart extraanatomical ascending-descending aortic bypass using a beating heart positioner in an adult with coarctation complicated by severe left ventricular hypertrophy. A 51-year-old woman was referred with severe hypertension. Computed tomography demonstrated severe distal aortic arch narrowing. Coarctation of the aorta was diagnosed. A posterior pericardial beating heart extraanatomical bypass via median sternotomy was performed from the ascending to descending aorta using a heart positioner. Her postoperative course was uneventful and blood pressure was normal on a low-dose beta-blocker.

Surgical repair of large aortocaval fistula with limited shunt: Case report

A 67-year-old man was admitted with severe back pain and bilateral lower limb swelling. Enhanced computed tomography showed an infrarenal abdominal aortic aneurysm (92 × 75 mm2) and a short aortocaval fistula (7 mm). Immediately afterward, circulatory collapse occurred, and the patient was rushed to the operating theater. A much larger aortocaval fistula (22 × 35 mm2) than that demonstrated by preoperative computed tomography was found and was repaired with a Dacron patch while using two balloon-tipped catheters to control bleeding. Then, the abdominal aortic aneurysm was replaced with a bifurcated graft. The patient’s postoperative course was uneventful. In this case, enhanced computed tomography detected the aortocaval fistula, but could not assess its size accurately. Successful surgical repair of an aortocaval fistula depends on early accurate delineation of the fistula and prompt control of bleeding.

Experimental Mitral Valve Plasty under the Beating Heart Guided by Real-Time 3-Dimensional Echocardiography

BACKGROUND This study examines whether real-time 3-dimensional echocardiography can provide an image resolution to serve as a substitute for optical visualization in performing mitral valve plasty. METHODS Three pigs were used in this study. A 3-dimensional echocardiographic system was evaluated on an epicardial surface. Beating heart mitral valve plasty was performed with a surgical stapler inserted from the apex of the left ventricle using only 3-dimensional echocardiographic visualization. RESULTS The high-quality images of the mitral valve were obtained with the probe at the epicardial position. However, by inserting the surgical instrument into the left ventricle, an acoustic shadow developed on the images. The images became indistinct because of the acoustic shadow, and operation became difficult. For the mitral valve plasty, an edge-to-edge mitral valve repair was carried out using a stapler (10 mm) under the beating heart. The stapler was confirmed to seize both leaflets evenly in only 1 of the 3 pigs. CONCLUSIONS Real-time 3-dimensional echocardiography provided clear 3-dimensional images of the mitral valve; however, when a surgical instrument was inserted into the left ventricle, an acoustic shadow appeared on the image and made detailed confirmation difficult. Lessening or eliminating the acoustic shadow would be a key point to improve this procedure.

Ischemic Changes in Evoked Spinal Cord Potentials During Profound Hypothermic Circulatory Arrest in Thoracic Aortic Surgery

PurposeWe examined the changes in evoked spinal cord potentials (ESCP) during profound hypothermic circulatory arrest to estimate the safe ischemic time.MethodsWe monitored ESCPs during surgery for descending thoracic or thoracoabdominal aneurysms in five patients. Evoked spinal cord potential recordings were obtained before cooling (baseline), then every few minutes during circulatory arrest, and at the end of the operation.ResultsAfter circulatory arrest, the amplitude of ESCPs decreased with time. We calculated the simple linear regression between the amplitude of ESCPs and the circulatory arrest time by the least-squares method, and found a highly linear relationship between amplitude and arrest time in all five patients. The time until disappearance of ESCPs was estimated as 50.7 ± 20.4 min (95% level of confidence).ConclusionWhen an ESCP disappeared, ischemic spinal cord injury had occurred. This demonstrates the potential value of estimating the time of disappearance of ESCPs to prevent ischemic spinal cord injury during descending thoracic aortic surgery.