Kazutoshi Tachibana

Evaluation of gastroepiploic arterial grafts to right coronary artery using transit-time flow measurement

OBJECTIVES The objective of this study was to analyse the relationship between the intraoperative transit-time flow measurement (TTFM) parameter values and the postoperative angiographic results of gastroepiploic arterial (GEA) grafts to the right coronary artery (RCA). We investigated whether the intraoperative TTFM parameter values are reliable indicators of early patency in GEA grafts to the RCA. METHODS Patients undergoing off-pump coronary artery bypass surgery with GEA grafts were included in this study. Eighty-three GEA grafts were individually anastomosed and examined by angiography 1 week after surgery. The quality of each graft was graded using FitzGibbon grading (Study 1) and graft-flow grading (Study 2). RESULTS Study 1: Seventy-two grafts were determined as Grade A and 11 as Grades B or O. There were no significant differences in the average of mean graft flow (MGF), pulsatility index or diastolic filling percentage between Grade A and Grades B or O grafts. Study 2: Sixty-two grafts were graded as good-graft dominant, 16 as bidirectional and 5 as occlusion including string. The average of the MGF, pulsatility index and diastolic filling percentage in the grafts graded as bidirectional and occlusion including string were not significantly different from those of grafts graded as good-graft dominant. CONCLUSIONS Previously reported cut-off values for intraoperative TTFM parameters could not be adapted for the early patency of GEA grafts to the RCA. However, the smoothness of the graft-flow curve may be a reliable predictor of postoperative graft patency.

Novel intraoperative evaluation for mitral valve regurgitation: retrograde cardioprotective beating test

In mitral valvuloplasty, the saline injection test is commonly employed. However, discrepancies in regurgitation between the naked eye findings during the saline injection test and the postoperative echocardiographical findings are noted. Here, we describe a technique that allows direct transatrial evaluation of the valve in the fully loaded, beating heart without the risks of air embolism. Physiological systolic mitral valve movement is reproduced under aortic cross-clamping. This novel evaluation enables a complete and safe mitral valve repair.

Surgical resection of primary cardiac lymphoma presenting as a huge mass: report of two cases.

Primary cardiac lymphoma (PCL) is a rare malignancy that is sometimes diagnosed at later stages because it is not associated with specific symptoms. Although chemotherapy is the standard for treating PCL, the value of surgical resection is controversial. We describe two patients who were treated by surgical resection and chemotherapy. Case 1 is a 37-year-old man with a history of acute lymphocytic leukemia and shortness of breath, and Case 2 is a 70-year-old woman with general fatigue. Both of them were presented at hospital. In Case 2, arrhythmic syncope occurred and direct current cardioversion was performed. Echocardiography showed a massive tumor in the right atrium and disturbed hemodynamics in both cases. The restricted venous return was alleviated by emergency surgery. The pathology report indicated primary cardiac lymphoma that was regressed by post-operative chemotherapy. A massive PCL should be surgically resected to prevent sudden death.

Renal cysts as strongest association with abdominal aortic aneurysm in elderly.

OBJECTIVE The aim of this study is to investigate the positive association between the presence of renal cysts and AAA. PATIENTS AND METHODS A retrospective chart review on the clinical data of 396 consecutive patients, who underwent CT scans for preoperative evaluation of thoracic and cardiovascular surgery in Sapporo Medical University from the period of January 2007 to December 2008, was conducted. RESULTS When comparing patients with renal cysts (n = 164) to those without (n = 233), there was a statistically significant difference between the presence of renal cysts and male gender (p = 0.007), hypertension (p = 0.003), and AAA (p < 0.001) on univariate analysis. In addition, when comparing patients with AAA to those without, although COPD but not AAA was associated with renal cysts in less than 65 years old, the presence of renal cysts was the strongest association with AAA among patients belonging to the 65 to 74 years old group and over 75 years old group on multivariate analysis. CONCLUSIONS There is a statistically higher incidence of renal cysts in patients with AAA compared to patients without AAA in the group of elder cardiovascular patients. It is likely that AAA and renal cysts share a common pathogenesis.

Utility of three-dimensional transesophageal echocardiography for diagnosis of unroofed coronary sinus

We report a case of unroofed coronary sinus (URCS) in a 42-year-old female. At an outpatient clinic, she was found to have an atrioventricular septal defect and mitral regurgitation with pulmonary hypertension, and she was transferred to our institute for surgical treatment. Both atrioventricular valves were located at the same level, and both the right atrium (RA) and right ventricle were enlarged on two-dimensional transthoracic echocardiography. Color Doppler imaging demonstrated severe mitral and tricuspid regurgitation and a left-to-right shunt from the left atrium (LA) to the RA. Although an ostium primum defect of the atrial septum was suspected, the exact position of the shunt flow was unclear. Two-dimensional transesophageal echocardiography (2D-TEE) could visualize a direct communication between the LA and coronary sinus. Three-dimensional transesophageal echocardiography (3D-TEE) clearly visualized the entire route from the coronary sinus into the LA and RA. The utility of 3D-TEE as a modality complementary to 2D-TEE in diagnosis of URCS was confirmed.

Acute Dilatation of the Ascending Aorta and Aortic Valve Regurgitation in Loeys-Dietz Syndrome

Loeys-Dietz syndrome (LDS) is a recently recognized connective tissue disorder caused by mutations of the transforming growth factor (TGF)-β receptors. It is an autosomal dominant syndrome characterized by the triad of arterial tortuosity and aneurysms, hypertelorism, and bifid uvula or cleft palate. We treated an 18-year-old woman with a 100-mm-diameter aortic root aneurysm and severe aortic valve regurgitation. She underwent urgent aortic root replacement and bioprosthetic valve implantation. LDS was diagnosed by postoperative genetic screening results. Histopathologic examination of the aortic wall showed diffuse degeneration and elastin fragmentation in the media.

Mycotic aneurysm of ascending aorta in an infant.

Mycotic aneurysm of the ascending aorta is rare in infants. A 12-month-old infant developed a mycotic aneurysm of the ascending aorta secondary to group A streptococcus septicemia. He developed atrioventricular block, and the rapid aneurysm progression under medical therapy prompted us to perform an emergency operation. The aneurysm was successfully repaired using an autologous pericardial patch. He remained well with normal sinus rhythm and was developing normally at the 5-year follow-up.

Harvesting: Tip and Pitfalls

Currently, the main graft materials used for coronary artery bypass grafting are the internal thoracic artery, radial artery, gastroepiploic artery, and saphenous vein. In this section, the characteristics of each graft and its harvesting, as well as essence of ultrasonic complete skeletonization, are described.

Successful diagnosis of pericardial rupture caused by blunt chest trauma using contrast ultrasonography

A 65-year-old male developed acute myocardial infarction due to coronary artery dissection and tricuspid valve injury after blunt chest trauma. Acute myocardial infarction was treated by coronary artery intervention; however, refractory heart failure with pleural effusion remained. The first transthoracic echocardiography (TTE) on admission failed to clearly visualize the tricuspid valve and right ventricle due to poor image quality. A follow-up TTE with contrast ultrasonography revealed pericardial rupture in addition to tricuspid regurgitation. Ruptures of the tricuspid papillary muscle and pericardium were confirmed during surgery and were repaired successfully. Blunt chest trauma results in various cardiac injuries including cardiac rupture, intramural hematoma, valvular injury, coronary artery injury, and electrical disturbances, leading to critical conditions and high mortality. Of such blunt trauma-induced injuries, coronary artery dissection, tricuspid valve injury, and pericardial rupture caused by blunt chest trauma are rare, and simultaneous occurrence of the three types of injuries that were successfully repaired has not been reported. In addition, this case indicates the utility of contrast ultrasonography for diagnosis of pericardial rupture caused by blunt chest trauma.

Reply to Kurkluoglu et al.

We thank Dr Kurkluoglu et al. for their extremely interesting letter that raises several fascinating points [1]. I fully agree with the anatomical pathway of the myocardium’s venous drainage [2]. However, I should mention the differences in the routes of effluent between antegrade and retrograde administration. The retrograde administration of the solution through the coronary sinus of the human heart has two general pathways of flow. The first is the greater venous system through the capillaries, coronary arteries and then exiting into the aortic root. In the human heart, approximately one quarter of retrograde cardioplegia follows this pathway. The other major avenue for the retrograde administration of the solution is through the venous channels that communicate with the ventricular chambers. In the clinical setting, it is noted commonly that a substantial fraction of retrograde solution is shunted into the ventricular chambers. In this experimental explanted human heart model, nearly 80% of the solution administered through the coronary sinus was recovered in the ventricular chambers [3]. Therefore, not much time was required for adequate volume loading to the left ventricle. The average time interval between terminal warm blood and heart beating was 8.1 ± 2.8 min. During this time interval, ring annuloplasty was usually performed to save time. In our series, no low-output syndrome and myocardial infarction occurred. However, the suggestion by Dr Kurkluoglu is rich in implication. It is important to obtain the developed left ventricular pressure information directly via the aortic root pressure monitoring port of the root vent needle [4]. Extremely high pressure may predispose to myocardial injury. In this case, the mean left ventricular pressure was 84.6 mmHg. All patients were readily weaned from cardiopulmonary bypass with a low-dose inotropic agent. According to our clinical data, no endocardial injury was suspected. Furthermore, we have been undertaking research on the mitochondrial ultrastructure of ventricular biopsy specimens. We will present the result in the near future. Then again, we would like to thank Dr Kurkluoglu et al. for their constructive comments and appreciate their interest in our report. We hope to augment further understanding and promote the widespread implementation of the retrograde cardioprotective beating test.