Age-related fibromuscular dysplasia in the human left ventricle papillary muscles arteries.

We describe histologically cases of patients between 31 and 60 years of age who had fibromuscular dysplasia (FMD) in the tunica media (TM) of the left ventricle papillary muscles (PM) arteries. We also compared them with our previous findings in subjects younger than 30 years of age. We examined histologically samples taken from the tip of the anterior PM of the left ventricle in 200 healthy male hearts. In 33 cases (16.5 %), FMD was in the TM. We divided these cases into three subgroups (A, B, C) based on the degree of replacement of smooth muscle cells by fibrous tissue, and thus identified 17, 11 and 5 cases, respectively. Until the age of 41, the typical lesions were often localized within the TM. Beyond that age, the fibrous tissue increased in the TM wall and in the surrounding area of the vessels, causing dysfunction of the PM. Degenerative lesions, as well as inflammatory infiltration, were found after the age of 53. The findings of this study will be useful to cardiologists and cardiac surgeons, in pointing out that, after the age of 44 years old, some PM and their supporting valves may present a degree of dysfunction.

Kugel's artery: an anatomical and angiographic study using a new technique.

In this study, we tried to resolve the confusion in the literature regarding the existence and course of Kugel's artery. With the aid of a new technique, we studied 100 human hearts ex vivo by radiography and by direct observation through dissection, to demonstrate anatomical and postmortem angiographic findings of Kugel's artery. Kugel's artery was found in only 6 hearts out of 100 (6%). It originated from the proximal left circumflex artery and ended in the right coronary artery in 2 cases; from the right coronary artery and ended in the same artery in 2 cases; from the left circumflex artery and ended in the same artery in 1 case; and from the right coronary artery through the sinus node artery, ending in the left circumflex artery, in 1 case. In all 100 hearts, an anastomotic network of small atrial branches was found in the same area (lower portion of the interatrial septum), connecting the large vessels indirectly. Branches of the sinus node artery in all hearts, and of the atrioventricular node artery in 66 hearts, participated in this network. Our procedure showed the detailed course of Kugel's artery and its course independent from the atrioventricular node artery and from the anastomotic network. In conclusion, in all cases an anastomotic network of small atrial branches courses through the lower interatrial septum and connects indirectly the proximal and distal ends of the larger coronary arteries. Kugel's artery provides an additional direct arterial anastomosis in the same area in 6% of the hearts.