SPONTANEOUS ECHO CONTRAST AND HEMORHEOLOGIC ABNORMALITIES IN CEREBROVASCULAR-DISEASE

Background and Purpose Spontaneous echo contrast (SEC) is thought to r epresent a risk factor for cardioembolic stroke. In vitro studies sugg est that SEC results from interaction between red cells and fibrinogen . To better understand the relation between SEC and stroke and to inve stigate the in vivo genesis of SEC, we examined the relation between S EC, the constituents of the blood, and plasma and serum viscosity in p atients with acute stroke or chronic cerebrovascular disease. Methods Fifty patients with acute stroke or chronic cerebrovascular disease re ferred for transesophageal echocardiogram (TEE) were studied by transt horacic echocardiography and TEE. Complete blood count, fibrinogen, al bumin, gamma-globulin, and plasma and serum viscosity determinations w ere made. Left atrial SEC was graded as absent, mild, or marked by mea ns of TEE. Results SEC was absent in 31 patients, mild in 10 patients, and marked in 9 patients. Higher grade of SEC was associated with a s ignificantly greater percentage of patients with atrial fibrillation a nd larger left atrial dimension. Atrial fibrillation was present in 23 % of the patients in the SEC absent group, 50% of the patients in the mild SEC group, and 78% of the patients in the marked SEC group (P<.01 ). Left atrial diameter averaged 3.8 +/- 0.6 cm in the SEC absent grou p, 4.3 +/- 1.1 in the mild SEC group, and 4.9 +/- 0.7 in the marked SE C group (P<.001). Hematocrit, white blood cell count, and platelet cou nt did not differ among the three groups. Fibrinogen, gamma-globulin, plasma viscosity, and serum viscosity values were all significantly hi gher in the presence of SEC (P<.05). Fibrinogen values were 361 +/- 97 mg/dL in the SEC absent group and 427 +/- 135 mg/dL in the marked SEC group. gamma-Globulin levels were 0.75 +/- 0.23 g/dL in the SEC absen t group and 1.06 +/- 0.48 g/dL in the marked SEC group. Both plasma vi scosity (1.97 cp) and serum viscosity (1.64 cp) were higher in the mar ked SEC group than in the SEC absent group (1.77 and 1.50 cp, respecti vely). Conclusions In patients with acute stroke or chronic cerebrovas cular disease, the severity of SEC was not related to albumin, hematoc rit, white cell count, or platelet count but rather to elevated fibrin ogen levels and concomitant increases in both plasma and serum viscosi ty. Moreover, increasing grade of SEC was associated with significantl y increased left atrial diameter and a higher percentage of patients i n atrial fibrillation.