november 2020 tracings · hypokalemia was due to diarrhea, resulting from a daily intake of 30...
TRANSCRIPT
Questions?Contact Dr. Nelson Visit the web site!
November 2020 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
www.nelsonsekgsite.com
November2020 Tracing 1 “Weak & tired” - Why?35 Year old woman Home
November2020
Tracing 1:Answer
This unhappy young woman had “anorexia nervosa,” and weighed in at 90 pounds.
The markedly long Q-T interval would support a diagnosis of “electrolyte derangement.”
Her values were: potassium = 1.6; magnesium = 1.9. Of interest, the marked hypokalemia was due to diarrhea, resulting from a daily intake of 30 tablets of the laxative “Correctol.”
P waves consistent with right atrial enlargement are reported to occur with hypokalemia.
“Weak & tired” - Why?35 Year old woman Home
November2020 Tracing 2 Name some causes that will
result in the rhythm below:47 Year old womanwith “Belly pain” Home
November2020
Tracing 2:Answer
Name some causes that will result in the rhythm below:
47 Year old womanwith “Belly pain”
This woman presented with acute pancreatitis and an EKG showing a markedly long “Q-T” interval. The time between the onsent of the QRS and beginning of the T wave (QOT Interval) is prolonged, and the T wave may be a combination of T + U waves. The electrolyte derangement of hypokalemia (2.7) And hypocalcemia (7) caused a long QT interval, and resulted in a lenghty run of irregualr polymorphic V.T. (“Torsades de pointes”)
Other causes of long QT that can result in Torsades include: 1. Antiarrhythmic drugs2. Psychotropic drugs3. Antihistamines, e.g. Seldane (OTM) 4. Antibiotics5. G.I. Drugs—propulsid (OTM)
OTM = off the market because of arrhythmias
Home
November2020 Tracing 3 Your observations:72 Year old man Home
November2020
Tracing 3:Answer
Your observations:72 Year old man
This interesting tracing shows a combination of first, second, and third-degree AV block in the same patient, recorded over a span of 15 minutes. The first strip shows first-degree block with a P-R interval of 0.28 at a rate of 60/minute. As the rate increases slightly from 60 to 70 in the strip of V6, second-degree block develops. The P-R interval is constant at 0.30 seconds, indicating the block is probably infranodal.
These leads were recorded as part of an intact tracing, and prompted an alert EKG technician to seek advice while the patient was “still hooked up.” The resulting apprehension in the woman evoked a rate increase to 110/min. This was an atrial challenge sufficiently rapid that none of the P waves were conducted.
The tracing is an excellent example of the frailty of AV transmission. When the bridge is “diseased,” changes in rate often result in varying degrees of AV block. The narrow QRS morphology of the escape pacemaker suggests that it arises in the His bundle. A ventricular pacemaker was inserted.
Home
November2020 Tracing 458 Year old man
ASHD - Unstable AnginaPlease complete
the ladder diagram Home
November2020
Tracing 4:Answer
58 Year old manASHD - Unstable Angina
Please complete the ladder diagram
The ladder diagram demonstrates sinus rhythm with some variation in the P-P cycle. Three of the four PVCs manage to sandwich themselves between successive P waves (interpolated PVCs). Minor variations in the coupling interval of sinus activation to the PVC, and the interlude between the PVC and the subsequent P wave (R-P interval) determine the fate of the sinus impulse occurring in the wake of the ectopic beat. There are interesting variations in the P-R intervals of the impulses that succeed in ventricular activation—variable degrees of conduction delay reflecting the timing of the stimulus in the refractory interlude of the AV junction caused by the PVC.
Lidocaine was successful in suppressing ventricular ectopy. Coronary arteriography showed severe three-vessel coronary artery disease with a high-grade left main coronary lesion, prompting coronary bypass surgery. Post-operatively, the ventricular ectopy did not recur.
Home
November2020
Tracing 584 Year old manRecurrent Syncope
Can you guess why? Home
November2020
Tracing 5:Answer84 Year old man
Recurrent SyncopeCan you guess why?
Here’s why!!
Sinus P waves are conducted with prolonged PR interval and “down-stream” RBBB. The Q waves in leads II, III, and AVF; prominent initial R waves in leads V1-V3; and Q waves in leads V5—V6 indicate an inferior-posterior lateral myocardial infarction (probably of recent occurrence).
If you guessed that syncope was due to AV block, you will be diappointed with the lower strip. Sinus activity suddenly ceases (“arrest”) and no escape pacemaker surfaces. An electronic pacemaker was inserted.
Home
November2020 Tracing 649 year old man
Would this rhythm cause symptoms??
(See below)
Would this??What is “spontaneous ventricular asystole”??
Home
November2020
Tracing 6: Answer
The top tracing shows typical 3:2 and 4:3 Wenckebach AV block and probably would not result in significant symptoms. However, rhythm strips in the bottom EKG could well put someone “on the floor.”
The abrupt appearance of the “run” of non-conducted B waves (here, at least eight) without an “escape” pacemaker surfacing is what Dr. Marriott has termed “spontaneous ventricular asystole.” The mechanics is uncertain, but probably represent profound vagatonic AV nodal suppression.
This man was in the early stages of an acute inferior myocardial infarction.
49 year old man
Would this rhythm cause symptoms??
(See below)
Would this??What is “spontaneous ventricular asystole”??
Home
November2020 BONUS TRACING: 44 Year old man
Scheduled for a T.M. test -Would you proceed?
Why or why not?Home
November2020
BONUS TRACING:Answer44 Year old man
Scheduled for a T.M. test -Would you proceed?
Why or why not?
The sinus rhythm is irregular and the dominant QRS morphology occurs with a short P-R interval and a prominent delta wave on the upstroke—a rather typical WPW pattern.
Significant repolarization abnormality accompanies the abnormal depolarization, and this would make any EKG changes—with standard exercise testing—impossible to interpret.
The narrow complexes are of interest. They are probably junctional in origin, and do not share access to the accessory pathway. They are conducted over the normal A-V bridge and show incomplete RBBB and an abnormal T wave vector in the frontal plane.
Home
November2020
BONUS TRACING:Answer (Continued)
Scheduled for a T.M. test -Would you proceed?
Why or why not?
Tracing During Treadmill Exercise
44 Year old man
A case in point. This young man applied for pilot training, which was refused because his routine EKG showed “ischemia.” A treadmill exercise test was performed with an interesting result.
During exercise, many of the QRS complexes showed a short PR interval and delta waves (arrows), indicating the presence of an accessory pathway. The WPW complexes have significant ST segment depression, not present in the normally conducted beats.
Happily, the conduction abnormality was recognized, or the incorrect diagnosis of “ischemia” would have continued.
Home