Yasuko Miyaki

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.

Endovascular stent-grafting of anastomotic pseudoaneurysms following thoracic aortic surgery

PurposeAnastomotic pseudoaneurysm is a rare but life-threatening complication after thoracic aortic surgery. Endovascular stent-grafting is a less invasive treatment for thoracic aortic aneurysm; however, its clinical usefulness for anastomotic pseudoaneurysms following thoracic aortic surgery is unclear.MethodsA series of 12 anastomotic pseudoaneurysms in 10 patients, which occurred following thoracic aortic surgery, underwent endovascular stent-grafting in our university hospital. Eight emergent endovascular stent-grafting cases were included in this study. A hand-made stent-graft, reconstructed by suturing graft material to an endoskeleton of modified Gianturco Z stents, was used in all cases.ResultsThe delivery success rate was 91.7%, and the hospital mortality rate was 25.0%. Two cases were converted to open surgery during the postoperative phase because of a type I endoleak. Complete absorption or shrinkage of the anastomotic pseudoaneurysm was observed in seven of nine cases.ConclusionEndovascular stent-grafting for patients with anastomotic pseudoaneurysms of the thoracic aorta following thoracic aortic surgery has become a possible optimal treatment. However, long-term outcome remains unclear, and periodical follow-up is required.

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.