Abstract. The incidence of embolism and atrial thrombosis in a necropsy material of patients with atrial fibrillation was studied. In all 642 patients were reviewed. The incidence of embolism was high and significantly higher (p<0.05) in the group with valvular heart disease and congenital heart lesions compared to a group with mainly arteriosclerotic and hypertensive heart disease.
The occurrence of embolism was not correlated to the number of conversions to sinus rhythm in either group. On the other hand, there was a lower incidence of embolism in atrial fibrillation of short duration compared to long duration. This difference, however, was significant (p<0.001) only in the non-valvular group.
These results are briefly discussed with regard to the indications for conversion of atrial fibrillation.