Frequency and Associations of Prosthetic Valve Fibrin Strands

Background- Filamentous fibrin strands (FSs) attached to valve prostheses have been well described in patients undergoing transesophageal echocardiography (TEE), but the frequency and clinical significance of these strands remain poorly defined. We aimed to determine the frequency of prosthetic valve strands and to assess their association with anticoagulant status, location, type, and number of prosthetic heart valves. Methods- In total, 300 consecutive patients with prosthetic heart valves, who were referred for clinically indicated TEE, were evaluated for the presence of FSs (defined as highly mobile, fine, filamentous masses with less than 1 mm thickness). Results- FSs were found in 141 (47%) patients. Significant associations were observed between the presence of FSs and anticoagulant status (P-value < 0.001). The location and number of the prosthetic valves had no statistically significant associations with the strands. The FSs were found more frequently on mechanical than on bioprosthetic valves (P-value = 0.004). A logistic regression model showed that greater values of international normalized ratio, bioprosthetic valves, and daily intake of ASA, had negative associations with the strands. Conclusions- There were significant associations between FSs and patients’ anticoagulation status; we would, therefore, suggest intense anticoagulation and close follow-up for these patients (Iranian Heart Journal 2008; 9 (4):23-31).