The Diagnostic Importance of Fibrillatory Wave Size

ERY LITTLE has been written on the analysis of the fibrillatory waves (f waves) of the electrocardiogram in atrial fibrillation in the differential diagnosis between rheumatic heart disease with mitral involvement and arteriosclerotic heart disease. In 1915 Hewlett and Wilson' reported one patient with atrial fibrillation whose f waves were larger, but attached no significance to the finding. Cookson2 in 1929 stated that the size of the f waves were "medium to large" in rheumatic heart disease and "medium to small" in other types of heart disease. In 1956 Osol3 found the voltage of the f waves greater in patients with rheumatic heart disease than in those with arteriosclerotic heart disease. The purpose of this investigation was to determine whether the differences in voltage of the f waves are sufficiently consistent to be useful in differentiating rheumatic heart disease and arteriosclerotic heart disease when atrial fibrillation is present.