Background and Purpose-In addition to advanced stenosis, earlier stages of carotid atherosclerosis are associated with the risk for stroke. However, the significance has not been established for specific stroke subtypes. This study examines the association of earlier carotid atherosclerosis with stroke subtypes. Methods-The subjects comprised 1059 patients (meanϮSD age, 62Ϯ11 years) with Ͻ60% carotid stenosis. With the use of ultrasound, carotid atherosclerosis was evaluated by the plaque score, as defined by the sum of all plaque heights in bilateral carotid arteries. On the basis of neurological signs and symptoms, medical history, and brain MRI, we diagnosed stroke and its subtypes as follows: no stroke (nϭ738), atherothrombotic infarction (AI) (nϭ56), lacunar infarction (LI) (nϭ117), cardioembolic infarction (nϭ65), cerebral hemorrhage (nϭ26), and other or unclassified stroke (nϭ57). Results-The plaque score was higher in AI (10.5Ϯ5.9) and LI (6.0Ϯ5.1) groups than in the no-stroke group (4.3Ϯ4.9) (both PϽ0.05), although it was similar between other stroke groups and the no-stroke group. Each 1 SD greater plaque score was associated with 2.5-fold (95% CI, 2.0 to 3.2) higher risk for AI and 1.4-fold (95% CI, 1.2 to 1.7) higher risk for LI compared with the no-stroke group. When we adjusted for cardiovascular risk factors, plaque score remained significantly associated with AI but not with LI. By receiver operating characteristic curve analyses, the receiver operating characteristic area for AI (0.81 to 0.86) was greater than that for LI (0.62 to 0.67) when we used plaque score either alone or in combination with cardiovascular risk factors. Conclusions-Although evaluation of carotid atherosclerosis may aid in the risk assessment for AI and LI, the benefit appears to be greater for AI.

Objective-Right ventricular regional contractility has been thought to be difficult to assess precisely. Cine magnetic resonance imaging with presaturation myocardial tagging was employed to quantitate the contraction of the right ventricular free wall and to identify normal performance compared with the left ventricle. Methods-Nine normal volunteers, aged 27-39 years, were examined in a 1 5 Tesla superconductive magnet, and short axis and four-chamber sections at the midventricular level were imaged with cine magnetic resonance sequences. Tags, applied at end diastole as two parallel black lines, intersected the mid-portion of the free wall, dividing it into upper, centre, and lower segments in the short axis section, and anterior, middle, and posterior segments in the four-chamber section. From a series of cine magnetic resonance images at 50 ms intervals over a cardiac cycle, end diastolic, and early, mid-, and end systolic images were chosen for calculation of the endocardial, epicardial, and mean percent fractional shortenings (%FS) in the six segments. Results-There was (1) a gradual increase in %FS in systole in both sections (P < 0 001, <0.005); (2) a poor transmural gradient of contractility; (3) a predominance of meridional shortening (whole length, mean end systolic %FS (SD): short axis, 17-4 (3.1)%; fourchamber, 30'1 (4.1)%; P < 0.001) in contrast to dominant circumferential shortening in the left ventricular lateral wall; (4) lower predominance of contractility in the short axis section (P < 0 001), and a middle dip of contractility in the four-chamber section (P < 0.005).Conclusions-Heterogeneity of contractility was closely correlated with the myocardial fibre architecture, and with wall stress determined by its thickness and curvature. It was proved that right ventricular regional function could be analysed non-invasively using cine magnetic resonance imaging with myocardial tagging. (Br HeartJ 1995;74:186-191) Keywords: Regional contraction; right ventricle; cine magnetic resonance imaging; presaturation tagging Although the significance of an assessment of right ventricular function is well recognised, especially for patients with congenital cardiac anomalies and with valvular heart diseases, no standard approach to this has been established because of the complex configuration and non-concentric nature of the contraction of the ventricle. Some basic indices reflecting the global function of the right ventricle, such as cavity volume and ejection fraction, can be estimated by using conventional angiocardiographyl-' or radionuclide scintigraphy,45 but the results lack accuracy and do not always reflect regional dysfunction. Right ventricular regional contractility, which may be more sensitive to maladaptation to overload, has been considered to be much more difficult to assess precisely than global function, and very few reports have appeared discussing regional contraction of the right ventricle even in experimental researches.67At the present time, we can easily depict the right ven...

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