In 310 patients with carotid territory stroke, we investigated whether a history of cardiac disease was more frequent among those with major stroke (n = 169) than among those with minor stroke (n = 141), and whether the two groups differed in values for blood variables directly or indirectly associated with stroke, each variable being adjusted for age and sex. A history of angina pectoris was more frequent in the major stroke than in the minor stroke group, 16% vs. 9% (p < 0.042; odds ratio, 2.2); and among female patients, a history of atrial fibrillation was more common in those with major stroke than in those with minor stroke, 35% vs. 13% (p < 0.033; odds ratio, 2.8). ESR (erythrocyte sedimentation rate) values were higher in the major than in the minor stroke group, 21 +/- 21 (mean +/- SD) vs. 15 +/- 14 mm/h (p < 0.028), as were WBC (white blood cell) counts, 9.4 +/- 3.2 vs. 7.9 +/- 2.3 x 109/l, p < 0.001. WBC counts were also higher in stroke survivors than in non-survivors, 9.6 +/- 3 vs. 8.3 +/- 3 x 109/l (p < 0.0027), as were serum creatinine values, 115 +/- 59 vs. 95 +/- 21 mumol/l (p < 0.0094). The differences between major and minor stroke patients may reflect differences in the degree of atherosclerosis and thrombogenicity