[Collateral blood flow showing dissection-like filling defect on coronary arteriography: a case report].

A 51-year-old man presented under a diagnosis of angina pectoris manifesting as exertional chest pain. First coronary angiography showed severe stenosis with ulceration and spontaneous dissection at the proximal right coronary artery and linear dissection-like filling defects extending to the distal right coronary artery. After about 3 months, repeat coronary angiography showed the previously observed stenosis with unclear dissection, and better developed collaterals from the left coronary artery to the right coronary artery showing the linear dissection-like filling defects. The bilateral coronary angiography did not clearly show filling defects. This phenomenon suggested that the collateral flows were related to filling of the defects. Intravascular ultrasonic imaging demonstrated severe atherosclerotic lesions at the proximal right coronary artery, but no dissection in the distal right coronary artery. Percutaneous transluminal coronary angioplasty for the stenosis was performed successfully with a stent. Coronary angiography after the angioplasty showed no collaterals, and the right ventricular branch appeared, suggesting that the linear dissection-like filling defects extending to the distal right coronary artery were due to the collateral flows. Filling defects extending distal to a severe stenosis must be distinguished carefully from coronary dissection.

Left atrial diverticulum associated with severe mitral regurgitation.

Diverticulum of the atrium is a rare and controversial clinical entity, and in the present case a left atrial diverticulum was associated with severe mitral regurgitation (MR). A 68-year-old female with the diagnosis of MR was referred for further cardiac evaluation. Echocardiography revealed severe MR and an accessory cavity behind an enlarged left atrium. She underwent surgical valve replacement, but excision of the diverticulum was not done because its rupture seemed unlikely. A follow-up computed tomography performed 8 months postoperatively demonstrated disappearance of the diverticulum. The etiology of this atrial diverticulum is not clear, but the patient's MR may have played a role in its development.

[Significance of atrial fibrillation, left atrial thrombus and severity of stenosis for risk of systemic embolism in patients with mitral stenosis].

The prognostic significance of atrial fibrillation, left atrial thrombus and the severity of mitral stenosis (MS) for systemic embolism was evaluated in 142 consecutive patients with MS (male 61, female 81; mean age 51 +/- 10 years) who were referred for cardiac catheterization. The relationships between systemic embolization, atrial fibrillation, left atrial thrombus and the size of mitral valve area obtained by the echocardiographic or Doppler method, or cardiac catheterization (Gorlin's formula) were studied. The effects of mitral regurgitation (MR) (Sellers II < or =) on systemic embolism or left atrial thrombus were also evaluated. Atrial fibrillation was observed in 117 patients (87%), 30 (28%) of whom had a history of systemic embolism. Four of 18 patients (22%) with sinus rhythm had a history of systemic embolism. Left atrial thrombus was observed in 63 patients (45%), including 17 (27%) with a history of systemic embolism. Seventeen (22%) of 76 patients without left atrial thrombus had a history of systemic embolism. Left atrial thrombus was detected in 17 of 41 (41%) patients with severe MS [mitral valve area (MVA) < or = 1.0 cm2], 8 of 25 (32%) patients with moderate MS (1.1 < MVA < or = 1.5 cm2), 2 of 14 (14%) patients with mild MS (MVA > or = 1.6 cm2), and embolization was complicated in 11% of cases of severe MS, 32% of cases of moderate MS and 21% of cases of mild MS. There was no significant difference between the 3 groups. Left atrial thrombus was more frequently observed in patients without MR than with MR (44% vs 13%, p < 0.05), but there was no significant difference in the incidence of embolism between the groups (28% vs 22%). Positive therapy intervention should be considered to prevent systemic embolism regardless of the presence or absence of sinus rhythm, MR, left atrial thrombus or severity of stenosis.