Relationship between regional severity of emphysema and coronary heart disease

We analyzed the relationship between regional severity of emphysema, which was evaluated by three-dimensional fractal analysis (3D-FA) of Technegas SP ECT images, and coronary heart disease (CHD). For 22 patients with emphysem a who underwent Technegas SPECT, we followed up CHD events, The follow-up p eriod was 5.4 +/- 0.5 (mean +/- SD) years. We defined the upper-lung fracta l dimension (U-FD) and lower-lung fractal dimension (L-FD) obtained with 3D -FA of Technegas SPECT images as the regional severity of emphysema. FD bec ame greater with the progression of emphysematous change. During the follow -up period, CHD events occurred in 6 (27%) of the 22 patients. Thr ratio of U-FD to L-FD for patients with CHD events (0.87 +/- 0.22) was significantl y smaller than for patients without CHD events (1.52 +/- 0.38) (p = 0.0015) . These findings suggest that severer emphysema in the lower lung indicates a higher risk of CHD than that in the upper lung.