Relationship between heart weight and the cross sectional area of the coronary ostia.

Sex variation in the area of the coronary ostia was studied in hearts with a normal weight (heart weight less than 400 g) and hypertrophic hearts (heart weight greater than or equal to 400 g). Also studied was a possible sex difference in the correlation between heart weight and the area of the coronary ostia. The study was performed on 379 post mortem hearts. In the group of hearts with a normal weight the area of the left coronary ostium in both sexes was greater than the right but the difference was statistically insignificant. There was no sex difference in the area of the left coronary ostium, whereas the area of the right coronary ostium was statistically significantly less in women. In the group of hyperthopic hearts the left coronary ostium increased in area with increasing heart weight. The difference in the area of the left coronary ostium between hearts with normal weight and hypertrophic hearts was stastically significant in men, but not in women. The right coronary ostium showed minimal increase in size with increasing heart weight and the difference in both sexes between the two groups was statistically insignificant. In the group of hypertrophic hearts the heart weight was best correlated to the area of the left coronary ostium in both sexes, but the values did not reach statistically significance. On the basis of this study the area of the right coronary ostium appears to be a bottleneck with regard to an adequate blood supply to a hypertrophic myocardium.