1. ID 175 – 58 year old man followed in the Cardiac Clinic because of coronary artery disease

2. ID 175 – 58 year old man followed in the Cardiac Clinic because of coronary artery disease Can you see P waves?

3. ID 175 – Normal sinus rhythm, 88/min. Yes. There is sinus rhythm, 88/min. Each P is followed by a QRS complex, with a constant P-R interval (140 msec)

4. ID 175 – Normal sinus rhythm, 88/min. There are no signs of right or left atrial enlargement

5. ID 175 Normal Sinus rhythm, 88/min. Left bundle branch block The QRS duration is prolonged (145 msec.), with a pattern of Left Bundle Branch Block (LBBB)

6. ID 165 Normal Sinus rhythm, 88/min. Left bundle branch block The presence of LBBB may mask the diagnosis of left ventricular hypertrophy and/or myocardial infarction

7. ID 165 Normal Sinus rhythm, 88/min. Left bundle branch block In left bundle branch block the abnormal depolarization is usually associated with secondary abnormal repolarization (ST depression and negative T in the leads showing a broad R wave)

8. ID 165 Final diagnosis: Normal Sinus rhythm, 88/min. Left bundle branch block