December 2018 Tracings

Transcription

1 Tracings Tracing 1 Tracing 4 Tracing 1 Answer Tracing 4 Answer Tracing 2 Tracing 5 Tracing 2 Answer Tracing 5 Answer Tracing 3 Tracing 6 Tracing 3 Answer Tracing 6 Answer Questions? Contact Dr. Nelson wpan747@gmail.com Visit the web site!

2 88 Year old woman. Tracing 1 What is phase 4 abberation?

3 88 Year old woman. Tracing 1: Answer What is phase 4 abberation? 85 There is sinus rhythm at 85/min. which is conducted with 3:2 Wenckebach A-V block. Usually, aberrant ventricle conduction occurs is phase 3 of the action potential, when incomplete repolarization if the right bundle is challenged by an atrial prematurity... resulting in RBBB. In phase 4, the bundles have recovered. If there is a delay in arrival of the next stimulus, the bundles think that they should behave as a pacemaker. The result is a non-propagated depolarization in the left bundle which ruins the conducting path. The arriving sinus stimulus is conducted with LBBB.

4 51 Year old man. 3-2:12 - Chest pain 3-2: :55 - Normal?? Tracing 2 Observations?

5 51 Year old man. Tracing 2: Answer Observations? 3-2:12 - Chest pain The top tracing shows diffuse ST depression suggesting a left main coronary artery disease. The 2nd tracing, after thrombolysis, shows marked regression of the ST changes. 3-2: :55 - Normal?? The bottom one, on its own, could be diagnosed as Early transition otherwise normal. Don t be reassured.. Coronary angios revealed 3 vessel disease and a significant left main lesion.

6 65 Year old man. Holter recording Tracing 3 Disturbed impulse formation? Conduction?

7 Tracing 3: Answer 65 Year old man. Holter recording Disturbed impulse formation? Conduction? C C F F 75 F F 35 F C This man was markedly symptomatic with dizziness and near syncope. As diagrammed, there is a sinus 75/ min. When the timing is just right some of the sinus impulses are conducted (C) with RBBB. When the P waves are blocked, a slow ventricular 35/min, appears. When the conducted impulse arrive at the time of the ventricular discharge, numerous fusion complexes (F) occur. The coincidence of the two impulses normalizes the QRS complex. The evident abnormal A-V conduction prompted pacemaker placement.

8 87 Year old man. A nifty example of V.T.!! Tracing 4 What features indicate this?? What other DXs??

9 87 Year old man. A nifty example of V.T.!! Tracing 4: Answer What features indicate this?? What other DXs?? The major diagnostic feature of ventricular tachycardia is AV dissociation with discrete P waves, fusion complexes (F) and capture beats (C). Absence of RS complexes in the precordial leads (Brugada Sign) is supportive. The marked ST segment elevation in the precordial leads indicates that the arrhythmia is occurring in the throws of acute anterolateral infarction... agree?? F C F

10 81 Year old woman. Tracing 5 Your choice: Typical A.V.N.R.T.? Atypical A.V.N.R.T.? Primary atrial tachycardia? A.V.R.T.?

11 81 Year old woman. Tracing 5: Answer Your choice: Typical A.V.N.R.T.? Atypical A.V.N.R.T.? Primary atrial tachycardia? A.V.R.T.? It is evident that the inverted P wave in front of the QRS complexes is responsible for this subventricular tachycardia. It is interrupted by an APC (lower arrow) indicating it is a reentrant mechanism. That would be evidence against primary atrial tachycardia. The earlier APC (upper arrow) does not alter the tachycardia and, thus, it would be unlikely that mechanism is AVRT utilizing an accessory pathway. The timing of the negative P waves eliminates typical AVNRT. Voilà, the best choice is atypicalavnrt. Do you agree??

12 35 year old man. Tracing 6 Your Observations please:

13 35 year old man. Tracing 6: Answer Your Observations please: This young man has Hypertrophic Obstructive Cardiomyopathy ( HOCM ). When the condition was first identified, the abnormal physical findings and ventricular anatomy resulted in a label of Idiopathic Hypertrophic Subaortic Stenosis -( IHSS ). Understandably, the large Q waves in leads I, avl, and V4-6 prompted a diagnosis of lateral wall M.I. However, leads V2-3-4 are half standardized, indicating that there is striking QRS voltage of left ventricular hypertrophy. (Note that the S wave depth in V2 is 56mm!). The abnormal muscle masses of HOCM can alter initial forces, resulting in Q waves. The directional change in early ventricular activation may cause various patterns, mistaken as inferior-or lateral-or anterior -or posterior MI.

14 Tracing 6: BONUS What is HOCM? The abbreviation stands for Hypertrophic Obstructive Cardiomyopathy. Asymmetrical hypertrophy of the ventricular septum, plus systolic anterior motion of the anterior leaflet of the mitral valve, results in variable obstruction of L.V. outflow. It should be evident that changes in L.V. volume will determine the degree of obstruction. A decrease will increase the narrowing.