1. Chronic Dermatomyositis with Intermittent Trifascicular Block
Paul R. Lightfoot, M.D., F.C.C.P., Saroja Bharati, M.D., Maurice Lev, M.D., F.C.C.P. 
CHEST 
Volume 71, Issue 3, Pages (March 1977)
DOI: /chest
Copyright © 1977 The American College of Chest Physicians Terms and Conditions

2. Figure 1
A (left). Leads 1, 2, and 3 during complete heart block. B (right). ECG showing 1:1 atrioventricular conduction with right bundle-branch block and left anterior hemiblock.
CHEST  , DOI: ( /chest )
Copyright © 1977 The American College of Chest Physicians Terms and Conditions

3. Figure 1
A (left). Leads 1, 2, and 3 during complete heart block. B (right). ECG showing 1:1 atrioventricular conduction with right bundle-branch block and left anterior hemiblock.
CHEST  , DOI: ( /chest )
Copyright © 1977 The American College of Chest Physicians Terms and Conditions

4. Figure 2
Intracardiac electrograms. Time lines indicate one-second intervals. From top to bottom are simultaneous surface lead 2, right atrial electrogram (RAE), and His bundle electrogram (HBE). A, Atrial activation; H, His bundle activation; and V, ventricular activation.
CHEST  , DOI: ( /chest )
Copyright © 1977 The American College of Chest Physicians Terms and Conditions

5. Figure 3
A (upper). First part of right bundle branch. (arrows). Note presence of only a few remaining cells in right bundle branch (Gomori's trichrome stain, original magnification × 150). B. (lower). Periphery of posterior fibers of left bundle branch (arrows). There is considerable fibrosis and loss of cells. V, Ventricular myocardium (Gomori's trichrome stain, original magnification × 45).
CHEST  , DOI: ( /chest )
Copyright © 1977 The American College of Chest Physicians Terms and Conditions

6. Figure 3
A (upper). First part of right bundle branch. (arrows). Note presence of only a few remaining cells in right bundle branch (Gomori's trichrome stain, original magnification × 150). B. (lower). Periphery of posterior fibers of left bundle branch (arrows). There is considerable fibrosis and loss of cells. V, Ventricular myocardium (Gomori's trichrome stain, original magnification × 45).
CHEST  , DOI: ( /chest )
Copyright © 1977 The American College of Chest Physicians Terms and Conditions