Hemodynamic factors of thrombus formation in coronary aneurysms associated with Kawasaki disease.
BACKGROUND
We studied the mechanism of thrombus formation in coronary aneurysms based on rheological findings.


METHODS
We studied 43 coronary aneurysms in 33 patients with Kawasaki disease (mean (+/- SD) age 6.1 +/- 4.3 years). These lesions were divided into three groups on the basis of maximum diameter: (i) small (group S); (ii) medium sized (group M); and (iii) large (group L) aneurysms. Using a Doppler flow guidewire and a pressure-monitoring guidewire, we measured coronary flow velocity and perfusion pressure inside aneurysms and in adjacent normal-looking vessels. We calculated the average peak velocity (APV) index, the mean coronary perfusion pressure (P) index and shear index.


RESULTS
The APV index and shear index decreased significantly (p < 0.005) as the aneurysm size increased (APV index in groups S, M and L was 0.893 +/- 0.149, 0.573 +/- 0.242 and 0.128 +/- 0.131, respectively; shear index in groups S, M and L was 0.750 +/- 0.149, 0.328 +/- 0.153 and 0.020 +/- 0.028, respectively). However, coronary perfusion pressure showed no relationship to aneurysm size and was not significantly different from that in adjacent normal-looking vessels.


CONCLUSIONS
The results of the present study suggest that the stagnation of flow and the reduction of shear stress in coronary aneurysms could initiate thrombus formation.
Kuramochi
Y
Y
Department of Pediatrics, Nippon Medical School, Tokyo, Japan. rio-ma7@nms.ac.jp
Ohkubo
T
T
Takechi
N
N
Fukumi
D
D
Uchikoba
Y
Y
Ogawa
S
S
D000293:Adolescent; D001783:Blood Flow Velocity; D002648:Child; D002675:Child, Preschool; D003323:Coronary Aneurysm / Q000150:complications* / Q000000981:diagnostic imaging; D017023:Coronary Angiography; D003328:Coronary Thrombosis / Q000209:etiology* / Q000503:physiopathology; D015150:Echocardiography, Doppler; D005260:Female; D005434:Flow Cytometry; D018056:Hemorheology; D006801:Humans; D007223:Infant; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000150:complications*