nida
Forum Elite
Topics: 23
Posts: 87
|
A 65-year-old male is seen in the emergency department with palpitations. His symptoms began 30 min before arrival. He has not had any dizziness, light-headedness, or chest pain. His past medical history is notable for a myocardial infarct 2 years ago, chronic atrial fibrillation, and a three-vessel coronary artery bypass graft surgery 1 year ago. Medications include aspirin, metoprolol, warfarin, and lisinopril. An electrocardiogram shows wide complex tachycardia at a rate of 170. Which of the following will prove definitively that his rhythm is ventricular tachycardia?
A. Hypotension
B. Cannon a waves
C. An odd electrocardiogram with similar QRS morphology
D. Irregular rhythm
E. Syncope
|
| achilles
Forum Guru
Topics: 89
Posts: 1,224
|
C ?
___________________
" it's not whether you get knocked down, it's whether you get up"
" i have miles to go before i sleep "
|
| karusmle
Forum Guru
Topics: 296
Posts: 1,001
|
even i go for c
|
| AAAAA
Forum Fanatic
Topics: 156
Posts: 1,991
|
C but wide QRS would be 90% accurate with underlying heart diseases !!
___________________
seeking study partner in USMLE, Canadian MCC OSCE examination
|
| dr in trouble
Forum Guru
Topics: 62
Posts: 601
|
what r cannon a waves and what r diff types of ECG
___________________
If u want to do something, do it today as there is no tomorrow.
|
| MAZI
Forum Elite
Topics: 8
Posts: 245
|
the charactristic feature of ventricular origin of tachyarrythmia:
in physical exam: cannon a wave( contraction of atria in the oposite ofthe closed atrioventricular valve that is seen with increase JVP during systol)
in ECG: capture beat & fusion complex (pathognomonic)
the answer is B
|
| Jinx
Forum Elite
Topics: 17
Posts: 316
|
b
___________________
Life is a journey--enjoy the drive!!
|
| nida
Forum Elite
Topics: 23
Posts: 87
|
The right answer is B) Cannon a waves.
The differentiation of ventricular tachycardia from supraventricular tachycardia with an aberration of intraventricuar conduction can be challenging and has important implications for management. By definition, however, ventricular tachycardia is associated with atrioventricular (AV) dissociation. Cannon a waves are found in the jugular venous pulsations when the atria are contracting against a closed tricuspid valve. This can occur only with AV dissociation, thus proving ventricular tachycardia. Hypotension, irregular rhythm, and syncope can all be seen in both ventricular tachycardia and supraventricuar tachycardia with aberrancy.
(From Harrison)
|
| achilles
Forum Guru
Topics: 89
Posts: 1,224
|
good question nida. thanks.
___________________
" it's not whether you get knocked down, it's whether you get up"
" i have miles to go before i sleep "
|
|
| |
| | | | | | | | | |
