Tomomitsu Oshima

Prediction of acute coronary syndromes by percutaneous coronary angioscopy in patients with stable angina.

To pinpoint the link between plaque characteristics and acute coronary syndromes, we performed a 12-month prospective follow-up study in 157 patients with stable angina pectoris in whom regular coronary plaques were observed by percutaneous coronary angioscopy. Acute coronary syndromes occurred more frequently in patients with yellow plaque than in those with white plaques (11 of 39 vs 4 of 118; p = 0.00021). Moreover, the syndromes occurred more frequently in patients with glistening yellow plaques than in those with nonglistening yellow plaques (9 of 13 vs 2 of 26; p = 0.00026). Thrombus arising from the ruptured identical plaques was confirmed by angioscopy as the culprit lesion of the syndromes. The results indicate that acute coronary syndromes occur frequently and in a short time in patients with glistening yellow plaques and that angioscopy but not angiography is feasible for prediction of the syndromes.

Possible Participation of Endothelial Cell Apoptosis of Coronary Microvessels in the Genesis of Takotsubo Cardiomyopathy

Takotsubo cardiomyopathy (TCM) is characterized by systolic ballooning of the left ventricular apex. It is triggered by emotional or physical stress, but the exact mechanism through which stress leads to TCM is not known.

Percutaneous fiberoptic angioscopy of the cardiac valves

The feasibility of percutaneous translumial angioscopy of the cardiac valves was examined in eight patients with and in 11 patients without valvular disease. In eight of these patients, a guiding balloon catheter (9F) was introduced into the aortic root, a guide wire (0.014 or 0.025 inch) was introduced through the catheter into the left ventricle to prevent dislocation of the catheter, and a fiberscope (1.6 or 4.6F) was advanced to the distal tip of the catheter. The balloon was then inflated with carbon dioxide and was manipulated against the aortic valve; a body temperature heparinized saline was infused through the catheter for observation. Similarly, the balloon catheter was advanced transseptally into the left atrium for observation of the mitral valve in four patients. Also, the balloon catheter was advanced through the right femoral vein into the right atrium for observation of the tricupid valve in three patients. In patients with a normal aortic valve, the aortic cusp surface was smooth and white and the edges were sharp. They opened briskly during systole and coapted each other completely during diastole. In rheumatic aortic regurgitation, the cuspus were thick and blunt and their coaptation insufficiency was observed during diastole. In a patient with rheumatic AS, globular and yellow cusps were observed. Mitral valve leaflets were smooth and white in a patients without mitral valvular disease, while the leaflets were yellow, thick and irregular, and blood regurgitation from the left ventricle into the left atrium could be observed in two patients with rheumatic MSR. The process of opening and closure of a tricuspid valve was also observed in three patients without tricuspid valvular disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioscopic detection of residual pulmonary thrombi in the differential diagnosis of pulmonary embolism

Definite diagnosis of pulmonary embolism (PE) by conventional methods such as angiography is frequently difficult. If residual thromboemboli incorporated into the pulmonary arterial wall or in the distal small segments are visible, differential diagnosis of PE versus primary pulmonary hypertension (PPH) can be made without open-chest pulmonary biopsy. Six patients suspected of having acute PE, 6 suspected of having chronic PE, and 4 with PPH diagnosed by pulmonary biopsy underwent percutaneous pulmonary angioscopy. In patients suspected of having PE, globular and mural thromboemboli were detected by both angioscopy and angiography in 4 and 1 patients, respectively. By angioscopy, emboli incorporated into the arterial wall were detected in 7 and microemboli obstructing the distal small segments were detected in 6. However, these emboli were detected by angiography in none. In patients with PPH, no embolus was detected by angioscopy and angiography. Angioscopically, however, stenoses were observed in the distal small segments in all patients. The results indicate that residual pulmonary thromboemboli in PE and stenoses of distal pulmonary arteries in PPH are detectable by percutaneous angioscopy, and therefore this method is feasible for differential diagnosis of PE.

Percutaneous fiberoptic angioscopy of the left ventricle in patients with dilated cardiomyopathy and acute myocarditis

Left ventricular luminal changes were examined by percutaneous fiberoptic angioscopy in 13 patients with dilated cardiomyopathy and in four patients with acute myocarditis. Angioscope-guided endomyocardial biopsy was also performed in six patients with dilated cardiomyopathy and in two with acute myocarditis. A balloon-tipped guiding catheter (9F) was introduced through the right femoral artery into the left ventricle, the balloon was inflated, and a 1.6 or 4.3F fiberscope was introduced through the catheter into the ventricle so as to locate the fiberscope tip at the tip of the catheter shaft. The balloon was then pushed against the desired portion of the ventricle and warmed saline was infused to observe the luminal changes. In contrast to the patients without organic heart disease whose left ventricular luminal surface was brown in color, the luminal surface was white or light yellow in four, light brown in one, bluish-white in one, with white and brown portions distributed in a mosaic pattern in four, and it was reddish brown in the remaining one patient with dilated cardiomyopathy. Mural thrombi were observed in two of the patients. The luminal surface was light brown in one, reddish brown in one, rose in one, and red in one patient with acute myocarditis. Thrombi and scattered bleeding were observed in two and one of these patients, respectively. The changes in luminal coloration in patients with dilated cardiomyopathy and acute myocarditis had no obvious relation to left ventricular volume and ejection fraction. Angioscope-guided biopsy revealed that the white and light yellow portions were due to endocardial fibrosis, that the endocardia of brown portions were not fibrotic, and that the myocardium in the red portions contained mononuclear cells, indicating inflammation. The results indicate that the angioscopic features of the left ventricular luminal surface were not uniform in patients with dilated cardiomyopathy or in those with acute myocarditis, and that angioscopy can be used as a guiding tool for endomyocardial biopsy.

Cardioscopic spectrum of the left ventricular endocardial surface and its relation to histologic changes in idiopathic myocarditis

To examine feasibility of percutaneous cardioscopy for diagnosis of idiopathic myocarditis, cardioscopic appearance of the left ventricle and biopsy findings were compared in 21 such patients. The endocardial surface was milky white, red, pink, or reddish brown and edematous at the segments that exhibited histologic changes of acute myocarditis; purplish red in those that exhibited chronic active myocarditis; and yellow in those that exhibited chronic inactive or healed myocarditis. Follow-up study by repeated cardioscopy and biopsy in six patients revealed that the milky white surface disappeared and that the red, pink, and reddish brown surfaces changed to purplish red and then to yellow or white. The results indicate that the endocardial coloration of the left ventricle represents histologic changes and that cardioscopy is feasible for macroscopic pathologic diagnosis and for follow-up of idiopathic myocarditis.

Angioscopic Evaluation of Stabilizing Effects of Bezafibrate on Coronary Plaques in Patients With Coronary Artery Disease

Background Since long-term administrations of anti-hyperlipidemic agents result in reduction in % stenosis or increase in minimum lumen diameter (MLD) of stenotic coronary segments, it is generally believed that anti-hyperlipidemic agents stabilize vulnerable coronary plaques. However, recent pathologic and angioscopic studies revealed that vulnerability of coronary plaques is not related to severity of stenosis and the rims rather than top of the plaques disrupt, and therefore, angiography is not adequate for evaluation of vulnerability. Angioscopy enables macroscopic pathological evaluation of the coronary plaques. Therefore, we carried out a prospective angioscopic open trial for evaluation of the stabilizing effects of bezafibrate on coronary plaques. Methods From April, 1997 to December, 1998, 24 patients underwent coronary angioscopy of the plaques in the non-targeted vessels during coronary interventions and 6 months later. The patients were divided into control (10 patients, 14 plaques) and bezafibrat (14 patients, 21 plaques) groups. Oral administration of bezafibrate (Bezatol SR, 400mg/day) was started immediately after the interventions and was continued for 6 months. The vulnerability score was determined based on angioscopic characteristics of plaques and it was compared before and 6 months later. Results Six months later, vulnerability score was reduced (from 1.6 to 0.8;p < 0.05) in bezafibrate group and unchanged (from 1.4 to 1.3; NS) in control group. In bezafibrate group, the changes in vulnerability score was not correlated with those in % stenosis or MLD. Conclusion The results indicate that bezafibrate can stabilize coronary plaques.

Percutaneous cardioscopy of the left ventricle in patients with myocarditis

The morphology and function of the cardiac chambers have been evaluated clinically using cineventriculography, computed tomography, magnetic resonance imaging, and endomyocardial biopsy. Excluding the invasive technique of biopsy where tissue is actually removed, these other non-invasive techniques reveal only indirect evidence of endocardial and subendocardial pathology and, therefore, allow the potential for misdiagnosis from insufficient data. Fiberoptic examinations, as recently demonstrated in coronary, pulmonary, and peripheral vessels, allow direct observation of pathology otherwise unobtainable. Recently, similar techniques have been applied to examine the cardiac chambers of dogs and the right heart of humans. In this study, we examine the feasibility and safety of percutaneous fiberoptic cardioscopy of the left ventricle in patients with myocarditis.

Diagnosis of cardiovascular lesions by percutaneous angioscopy and intravascular ultrasound

We performed simultaneous angioscopy and intravascular ultrasound imaging (IVUS) to evaluate the luminal changes of cardiac chambers, valves and vessels in patients with various categories of cardiovascular disease. We observed cardiac chambers in 7, coronary arteries in 3, aortic valve in 6, aorta in 10, vena cava in 2, pulmonary arteries in 3 and femoral arteries in 5 pts. The angioscopy was suitable for detection of the changes in color and for 3D evaluation of small changes. The IVUS was suitable for detection of calcified tissues and for evaluation of cardiac and vessel wall structures. Furthermore, we could observe dynamic motion of the cardiac valves by the IVUS. The results indicate that simultaneous observation by IVUS and angioscopy gives us much more information on the cardiovascular changes.

Percutaneous transluminal angioscopy of the pulmonary artery

The morphologic changes of the pulmonary artery have been observed by angiography, but angiography shows only the shadows of the changes actually occurring. Recent advances in fiberscopic technology enabled us to observe the coronary artery, great vessels, cardiac chambers and the pulmonary artery by angioscopy4 We report here angioscopic features of the pulmonary artery in patients with pulmonary thromboernbolism, pulmonary hypertension and rheumatic valvular disease.