VOL. III NO. 3 Circulation 'The Journal of the American 1Hart Association

Acute nonspecific pericarditis has been recognized with increasing frequency in recent years al-though there is reason to believe that it was considered distinct from rheumatic pericarditis almost 100 years ago. The authors have been able to secure follow-up information on 50 cases seen be-tween 1930 and 1949. A few have shown persistent electrocardiographic changes, and calcifica-tion of the pericardium occurred in 1 case. In general the prognosis appears excellent and we have not observed constrictive pericarditis as a sequela. IN RECENT years the syndrome of acute nonspecific pericarditis has stimulated the interest of clinicians in increasing degree. The frequency of this condition and its poten-tial relationship to chronic constrictive peri-carditis prompted us to review the experience with this form of pericarditis at the Massa-chusetts General Hospital. The study consists of two parts: a review of the clinical and lab-oratory aspects of this syndrome and a fol-low-up study of these patients. Fifty cases were reviewed whose acute illness occurred in the two decades from 1930 to 1949, and long-term observations were obtained on those patients whose illness antedated this study by more than two years. HISTORICAL BACKGROUND Ninety-six years ago there appeared in the Boston Medical and Surgical Journal a cas