Hydrothorax in congestive heart failure

At autopsy, of 290 patients with hydrothorax due to congestive heart failure, twentyfour had unilateral right-sided hydrothorax, eleven had unilateral left-sided hydrothorax and 255 had bilateral hydrothorax. Thus, the incidence of right and left hydrothorax was approximately equal as 279 of the 290 patients had right-sided hydrothorax and 266 patients had left-sided hydrothorax. In every category of heart disease except mitral heart disease, combined left and right failure predominated over right failure only. In our series auricular fibrillation was more commonly associated with unilateral left-sided hydrothorax than with unilateral right-sided hydrothorax. Percentage-wise, pulmonary edema was more frequently encountered among those patients with unilateral pleural effusion on the left side than among those with unilateral pleural effusion on the right side.