Cheruvu PK et al. (2007) Frequency and distribution of thin-cap fibroatheroma and ruptured plaques in human coronary arteries: a pathologic study. J Am Coll Cardiol 50: 940–949

Acute coronary syndromes are usually caused by the rupture of vulnerable plaques, leading to thrombosis. It remains unclear, however, how these plaques are distributed throughout the coronary arterial tree.

Cheruvu et al. studied the prevalence and location of atheromatous plaques in 50 human hearts. The right coronary, left circumflex and left anterior descending arteries were resected and cut into 20 mm longitudinal sections. Further graphical analysis was performed using 3 mm segments, 3,639 of which were available in all.

The prevalence of thin-cap fibroatheroma (TCFA) and ruptured plaques was low. Overall, 23 TCFAs and 19 ruptured plaques were identified from a total of 212 advanced coronary lesions, the majority of which were non-atheromatous. Among the 20 hearts that contained at least one TCFA or ruptured plaque, the mean (± SD) numbers of these lesions per heart, were 1.15 ± 1.23 and 0.95 ± 0.83, respectively.

TCFA and ruptured plaques tended to cluster, particularly in the left anterior descending and left circumflex arteries, in which 90% of these lesions were found within the first 22 mm. In 16 of the 20 hearts that contained either of these lesions, all were located within two or fewer 20 mm sections. In 11 of these hearts, less than 10 mm of total coronary length was occupied by these lesions.

These findings suggest a focal distribution of vulnerable coronary plaques. Identifying these high-risk areas could facilitate the stabilization of plaques before rupture.