1. Volume 77, Issue 4, Pages 499-505 (April 1980)
Mechanism and Time Course of the Early Electrical Changes During Acute Coronary Artery Occlusion 
Juan Cinca, M.D., Michiel J. Janse, M.D., Hervé Moréna, M.D., Jaime Candell, M.D., Vicente Valle, M.D., Dirk Durrer, M.D., F.C.C.P. 
CHEST 
Volume 77, Issue 4, Pages (April 1980)
DOI: /chest
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

2. Figure 1
ECG recorded during a nocturnal attack of chest pain (A) and 5 minutes later when symptoms had disappeared (calibration 1 mV and 1 sec).
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

3. Figure 2
Precordial leads before (A) and during initial stages of acute myocardial infarction. Time is given in minutes following the beginning of acute chest pain. Last panel was recorded 24 hours later.
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

4. Figure 3
Alternation in precordial leads V2 to V5 3 minutes after onset of chest pain (A). In B, recorded 8 minutes after beginning of pain, alternation has disappeared.
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

5. Figure 4
Transmembrane potentials (upper tracings) and local DC-extracellular electrograms (lower tracings) before (control) and 3 minutes and 10 sec following occlusion of left anterior descending artery in an isolated, perfused porcine heart. Zero levels for transmembrane recordings is obtained when recording and reference microelectrode are both in the extracellular space (straight line in upper traces). Zero level for extracellular recording (straight line in the lower traces) is the DC-potential of aortic root. Note decrease in resting transmembrane potentials during ischemia results in depression of TQ segment. Delayed activation gives rise to late intrinsic deflections in extracellular electrogram and to an increase in R wave due to lack of cancellation.
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

6. Figure 5
Transmembrane potentials (top tracings) and local DC extracellular electrogram from another experiment before (control) and 4 and 7 minutes after occlusion of left anterior descending artery in an isolated pig heart. Note alternation after 4 minutes in action potential amplitude and duration and the concomitant alternation in ST segment in extracellular complexes. Note very small transmembrane after 7 minutes associated with nearly monophasic extracellular complexes.
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

7. Figure 6
Transmembrane potentials and extracellular electrograms from another experiment before and after occlusion of left anterior descending artery. Increase in action potential amplitude and upstroke velocity after 30 minutes of ischemia, as compared to situation 8 minutes after coronary artery occlusion, is reflected in large, fast intrinsic deflection of the extracellular complex (arrow).
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

8. Figure 7
A (left), transmembrane potentials (upper tracing) and local DC extracellular electrograms (lower tracing) before coronary artery occlusion. B (right), alternation in action potential amplitude and duration 5 minutes after coronary artery occlusion. Note that smaller action potential gives rise to a larger ST elevation; negative T wave reflects long action potential duration, positive T wave, a short duration. In diagram, normal and ischemic potentials are superimposed and current flow between ischemic and normal cells is schematically depicted at moments one and two (dotted lines).
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions

9. Figure 7
A (left), transmembrane potentials (upper tracing) and local DC extracellular electrograms (lower tracing) before coronary artery occlusion. B (right), alternation in action potential amplitude and duration 5 minutes after coronary artery occlusion. Note that smaller action potential gives rise to a larger ST elevation; negative T wave reflects long action potential duration, positive T wave, a short duration. In diagram, normal and ischemic potentials are superimposed and current flow between ischemic and normal cells is schematically depicted at moments one and two (dotted lines).
CHEST  , DOI: ( /chest )
Copyright © 1980 The American College of Chest Physicians Terms and Conditions