Background and aim of the study: Early recognition of subclinical prosthetic valve malfunction may promote early treatment and avoidance of serious complications. Echocardiography cannot be applied on a daily basis; thus, a hand-held device (Thrombocheck©) which is capable of detecting subtle changes in the acoustic sounds of prosthetic valve has been developed for the routine home monitoring of heart valve function. Herein is reported the authors’ initial clinical experience with this device.
Methods: Seventy-one consecutive patients with one or more bileaflet prosthetic mechanical valves at any position were assessed both by transthoracic echocardiography (TTE) and by Thrombocheck. These patients attended the authors’ clinic for either routine echocardiography (n = 62) or for the detection of prosthetic valve malfunction (n = 9). Cinefluoroscopy and transesophageal echocardiography were used selectively to confirm prosthetic valve malfunction.

The Thrombocheck was held for 1 min in the subxiphoid position perpendicular to the patient, and indicated either normal function (OK), abnormal function (Warning) or ‘no signal’.
Results: The study patients had in total 82 bileaflet valves (47 mitral, 31 aortic, four tricuspid). Eight patients (11.3%) had a ‘no signal’ indication. Of the remaining 63 patients, 10 (15.9%) had a ‘warning’ alarm (eight patients had current abnormal leaflet motion, one patient had a recent history of abnormal leaflet motion, and one had no evidence of prosthetic valve malfunction). The sensitivity and specificity for detecting abnormal prosthetic valve malfunction were 90% and 98%, respectively.
Conclusion: The Thrombocheck had an excellent sensitivity and specificity for the detection of prosthetic valve malfunction in a cohort of patients with bileaflet mechanical prosthetic heart valves.
The Journal of Heart Valve Disease 2005;14:476-480