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A 65-year-old man presents to the emergency department complaining of palpitations that started 20 minutes ago. He states he had a "heart attack" one year ago. He smoked for twenty years and has had diabetes for ten years. He watches his diet and takes aspirin and atorvastatin. On physical examination, you find a heart rate of 145/min, a blood pressure of 148/85 mm Hg, and a respiratory rate of 22/min. He has intermittent waves in his jugular veins consistent with canon "a" waves, and his lungs are clear. The S1 varies in intensity. The EKG shows that the QRS complex is approximately 0.16 seconds in duration, with dissociation of the p waves from the QRS complexes. All the QRS complexes are positively deflected in all leads. How would you treat this gentleman?
(A) Verapamil
(B) Cardioversion
© Adenosine
(D) Insert a pacing catheter
(E) Procainamide
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cana a wave see in tr & comlete heart block.
dddddddd
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Answer:
(E) Procainamide
Explanation:
This patient has ventricular tachycardia based on the presence of a wide complex tachycardia and cannon "a" waves in the jugular veins. Cannon "a" waves are due to the unsynchronized contraction of the ventricles and the atria. This results in a retrograde flow of blood back to the jugular veins with atrial systole. The variation of the intensity of S1 is caused by the ventricle contracting at times when the AV valves are open and at other times when they are closed. Procainamide, amiodarone, and lidocaine are the most effective treatments for a hemodynamically stable patient.
Verapamil and adenosine can be dangerous in a patient like this. Verapamil is useful in supraventricular tachycardia (SVT), not ventricular tachycardia. Verapamil can decrease blood pressure. Adenosine is useful only for SVT. Inserting a pacing catheter into the apex of the right ventricle and trying to terminate the tachycardia by override pacing is indicated in a stable patient who does not respond to medication. Cardioversion is used for hemodynamically unstable patients. Beta-blockers post-myocardial infarction decrease the occurrence of arrhythmias, such as those seen in this patient.
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i dnt know u r saying that adenosine is used only in svts but kaplan says vt also.its written in the kaplan table adenosine indication is vantricular tachycardia.
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adenosine is only for SVT, not VT.
procanamide for both svt and vt.
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Thank you for posting a very good question.
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Adenosine is one disease drug--only for SVT.
