Mehl. tamponade, TDP, AV block, waves - T, U, delta, J,

Question 1

Mehl. Pericardial effusion / Cardiac tamponade.

Cardiac tamponade =?

Answer 1

pericardial effusion + low blood pressure.

Question 2

Mehl. Pericardial effusion / Cardiac tamponade.

pericardial effusion + low blood pressure = ?

Answer 2

Cardiac tamponade

Question 3

Mehl. Pericardial effusion / Cardiac tamponade. What determines whether we have a tamponade or not?

Answer 3

the rate of accumulation of the fluid, not the volume of the fluid.

i.e., a stab wound or post-MI LV free-wall rupture resulting in fast blood accumulation, even if smaller volume, might cause tamponade, but cancer resulting in slow, but large, accumulation might not cause tamponade.

Question 4

Mehl. Pericardial effusion / Cardiac tamponade.

Tamponade presents as Beck triad: ?

Answer 4

1) hypotension, 2) JVD, 3) muffled/distant heart sounds.

The question will basically always give hypotension and JVD. Occasionally they might not mention the heart sounds. But you need to memorize Beck triad as HY for tamponade.

Question 5

Mehl. Pericardial effusion / Cardiac tamponade. what presentation in tamponade? specific

Answer 5

Pulsus paradoxus (i.e., drop in systolic BP >10 mm Hg with inspiration) is classically associated with tamponade, although not frequently mentioned in vignettes. I’ve seen a 2CK NBME Q where they say “the pulsus paradoxus is <10 mm Hg,” which is their way of saying the Dx is not tamponade. I consider that wording odd, but it’s what the vignette says.

Question 6

Mehl. Pericardial effusion / Cardiac tamponade.

drop in systolic BP >10 mm Hg with inspiration, name?

Answer 6

Pulsus paradoxus

Question 7

Mehl. Pericardial effusion / Cardiac tamponade. ECG?

Answer 7

ECG will show electrical alternans / low-voltage QRS complexes.

Question 8

Mehl. Pericardial effusion / Cardiac tamponade.

You can see the amplitudes (i.e., heights) of the complexes are short. This refers to “low-voltage.” You can also see the heights ever so slightly oscillate up and down. This refers to electrical alternans. They show this ECG twice on 2CK NBMEs.

Answer 8

.

Question 9

Mehl. Pericardial effusion / Cardiac tamponade. If the Q asks for next best step in diagnosis???

Answer 9

Choose ECG as first step if listed If not listed, then choose echocardiography, which confirms fluid over the heart.

Question 10

Mehl. Pericardial effusion / Cardiac tamponade. If the Q asks for next best step in management for tamponade when the vignette is obvious, choose ??? 2

Answer 10

pericardiocentesis or pericardial window. USMLE will not list both; it will be one or the other. NBME 8 offline for 2CK has pericardial window as answer, where pericardiocentesis isn’t listed.

Question 11

Mehl. Torsades de pointes (TdP). HY type of VT that has sinusoidal pattern on ECG.

Answer 11

.

Question 12

Mehl. Torsades de pointes (TdP). USMLE wants you to know this can be caused by some anti-arrhythmic agents, such as the sodium- and potassium-channel blockers? 2

Answer 12

such as quinidine and ibutilide, respectively.

Question 13

Mehl. Torsades de pointes (TdP). They ask this directly on the NBME exam, where Q will say patient is given ibutilide + what is he now at increased risk of?

Answer 13

torsades.

Question 14

Mehl. Torsades de pointes (TdP). risk factor for development of TdP?

Answer 14

QT prolongation is

Question 15

Mehl. Torsades de pointes (TdP). 3 drugs that prolong QT?

Answer 15

Agents such as anti- psychotics, macrolides, and metoclopramide prolong the QT.

Question 16

Mehl. Torsades de pointes (TdP). Tx?

Answer 16

Tx USMLE wants is magnesium (asked directly on new 2CK form), which stabilizes the myocardium in TdP.

Question 17

Mehl. Peaked T wave. In what pathology?

Answer 17

hyperkalemia

Question 18

Mehl. Peaked T wave. Tx?

Answer 18

Highest yield point is that if a patient has hyperkalemia and ECG changes, the Tx USMLE wants is IV calcium gluconate or calcium chloride, which stabilizes the myocardium. Calcium gluconate is classic, but calcium chloride shows up as an answer on a 2CK NBME.

Question 19

Mehl. U-wave. in what pathology?

Answer 19

HYPOkalemia

Question 20

Mehl. U-wave. In what GI/psych pathology can occur?

Answer 20

Shows up on NBME 12 for 2CK in anorexia patient. First time I’ve ever seen it show up anywhere on NBME material. But Q doesn’t ride on you knowing it means hypokalemia to get it right. It’s HY and pass-level to know that purging (anorexia or bulimia) causes hypokalemia anyway.

Question 21

Mehl. Delta wave. In what pathology?

Answer 21

Seen in Wolff-Parkinson-White syndrome (WPW; accessory conduction pathway in heart that bypasses the AV node, resulting in reentrant SVT).
- Classically described as a “slurred upstroke” of the QRS, where the PR interval is shortened.

Question 22

Mehl. Delta wave.
Both the delta-wave and WPW have basically nonexistent yieldness on USMLE, but I mention them here so you are minimally aware.

Answer 22

.

Question 23

Mehl. J waves. what does it mean?

Answer 23

They mean hypothermia. You don’t need to be able to identify on ECG. Just know they exist, as they show up in a 2CK vignette where patient has body temperature of 89.6 F (not 98.6).

Question 24

Mehl. AV. First degree block. PR duration?

Answer 24

Prolonged PR interval (>200 ms). Should normally be 80-120 ms.

PR is extra long - vizualiai matosi

Question 25

Mehl. AV. Prolonged PR interval (>200 ms). Should normally be 80-120 ms. What degree?

Answer 25

First degree block

Question 26

Mehl. AV. First degree block, Tx?

Answer 26

Not really assessed on USMLE. Just know the definition. Don’t treat on USMLE.

Question 27

Mehl. AV. Second degree Mobitz type I (aka Wenckebach). ECG?

Answer 27

Gradually prolonging PR interval until QRS drops. Then cycle repeats.

Question 28

Mehl. AV. Gradually prolonging PR interval until QRS drops. Then cycle repeats.

Answer 28

Second degree Mobitz type I (aka Wenckebach).

Question 29

Mehl. AV. Second degree Mobitz type I (aka Wenckebach). Tx?

Answer 29

Don’t treat on USMLE.

Question 30

Mehl. AV. Second degree Mobitz type II. ECG?

Answer 30

No gradual prolongation of PR interval, followed by a random dropping of the QRS.

Question 31

Mehl. AV. No gradual prolongation of PR interval, followed by a random dropping of the QRS. Block?

Answer 31

Second degree Mobitz type II

Question 32

Mehl. AV. Second degree Mobitz type II. Can also sometimes occur as patterns of 2:1, 3:1, etc., where there will be a P to QRS ratio of 2:1 or 3:1, etc.

Answer 32

Regardless as to whether the dropped QRS is random or in a numerical pattern, there is no gradual prolongation of the QRS before the dropped complex.

Question 33

Mehl. AV. Second degree Mobitz type II. MORE DANGEROUS THAN Mobitz I.

Answer 33

This is because Mobitz II has higher chance of progression into type III heart block.

Question 34

Mehl. AV. Second degree Mobitz type II. Tx?

Answer 34

Treatment on USMLE is insertion of pacemaker. This is asked on a new 2CK NBME exam.

Question 35

Mehl. AV. Third degree. Two things you want to look for on ECG:

Answer 35

- 1) Ultra-slow HR (i.e., 30-40). You’ll see the QRS’s are super far apart. This is the ventricular escape rhythm. - 2) No relationship between the P-waves and QRS complexes.

Question 36

Mehl. AV. - 1) Ultra-slow HR (i.e., 30-40). You’ll see the QRS’s are super far apart. This is the ventricular escape rhythm. - 2) No relationship between the P-waves and QRS complexes. block?

Answer 36

Third degree.

Question 37

Mehl. AV. Third degree. Tx?

Answer 37

Treatment on USMLE is insertion of pacemaker.

Question 38

Mehl. AV. So what you want to remember is that Mobitz II and 3rd-degree are the ones where we insert pacemaker; 1st-degree and Mobitz I we don’t.

Answer 38

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