Sketchy Path: Acute Myocardial Infarction and Post-MI Timeline

Question 1

What are the symptoms of an MI?

Answer 1

• Anxiety
• Diaphoresis
• Crushing substernal chest pain that can radiate to the arm or jaw
• Dyspnea

(All of this is represented by the jester: he’s anxious about being crushed by the anvil and he’s holding the broken heart string lute.)

Question 2

What happens to cardiac function during an MI?

Answer 2

Decreased cardiac output (like the floppy heart balloon behind the jester)

Question 3

Most MIs occur due to occlusions of the ___________.

Answer 3

left anterior descending (like the LADy yelling in the young king’s left ear –she has a red left anterior braid)

Question 4

What symptoms most often arise from occlusion of the LAD?

Answer 4

Left heart failure: pulmonary edema evidence by bibasilar crackles (like the LADy’s tunic that is wet on the bottom)

This is also why dyspnea can arise from MIs! (Think of the servant the LADy is pushing out of the way –he’s exhaling uncomfortably.)

Question 5

Acute MIs can produce what gallop?

Answer 5

S4 (like the 4-shaped chair that the young king is sitting on)

Question 6

What are the two most common causes of death during or very soon after an MI?

Answer 6

• Arrhythmias such as ventricular fibrillation (like the quivering, heart-shaped accordion next to the dead jester from the last ceremony)
• Cardiogenic shock (like the heart with the lightning bolt through it behind the servant)

Question 7

What are symptoms of right coronary MI?

Answer 7

• ST elevation in leads II, III, and aVF (like the II, III, and F on the knight’s shield –who is standing on the young king’s right)
• Bradyarrhythmia due to the lack of blood to the SA node (like the knight’s falling clock)
• Heart block due to ischemia in the AV node (like the knight’s heart block shield)
• Right heart failure with JVD and liver congestion (like the dilated blue JUG)

Question 8

What happens to heart tissue during the 0-4 hour window after an MI?

Answer 8

Nothing –histologic and macroscopic findings will be normal

Think of the jester with FOUR clocks on his hat: his tunic shows normal myocardium.

Question 9

What happens to heart tissue during the 4-12 hour window after an MI?

Answer 9

Wavy bands of degenerating myocytes appear with brief hints of coagulative necrosis

(Think of the next jester with the sun-moon face, representing a half day or twelve hours, who has wavy tassels on his tunic and he’s about to fall into the skull pit. The fact that he’s about to fall indicates that coagulative necrosis is just beginning.)

Also, punctate hemorrhages appear (like the blood drops beneath the jester’s feet)

Question 10

What happens to heart tissue during the 12-24 hour window after an MI?

Answer 10

Coagulative necrosis with contraction bands

Think of the jester with the sun mask who is wearing the shirt that has faded pink stripes and contraction bands.

Question 11

What happens to heart tissue during the 1-3 day window after an MI?

Answer 11

Extensive coagulative necrosis with neutrophil infiltration

(Think of the fourth jester who has three suns on his shirt: he has a faded pink-stripe tunic with purple dots to indicate neutrophils. Also, the first responders are primarily there to help him.)

Question 12

What is a common complication during the neutrophil phase post-MI?

Answer 12

Early-onset pericarditis

(Think of the guitar case –symbolizing the pericardium –rubbing down the trap door like the friction rub of pericarditis. This typically is only over the area of necrosis.)

Question 13

What happens to heart tissue during the 3-14 day window after an MI?

Answer 13

Macrophage infiltrate with granulation tissue

(Think of the jester next to the knight with the half-moon shield –representing 14 days for the 3-14 day window –who has a purple shirt. Also, his GRANny is mourning his injuries next to the CAGE he’s in.)

Question 14

What are the three types of myocyte rupture that can occur during the granulation phase?

Answer 14

• Papillary muscle rupture with subsequent mitral regurgitation (like the broken instrument holding the heart strings of the instrument by the GRANny’s feet)
• Ventricular free wall rupture
• Interventricular septal rupture (like the guy with the broken tambourine)

Question 15

Papillary muscle rupture most commonly occurs following occlusion of which coronary?

Answer 15

The posterior descending (like how the right branch of the jester’s hat is poking over the diagram of the holosystolic murmur)

Question 16

Occlusion of which artery leads to interventricular wall rupture?

Answer 16

The LAD (like how the left branch of the jester’s hat descends over the broken tambourine)

Question 17

It can be hard to differentiate papillary muscle rupture from interventricular septal rupture because ______________.

Answer 17

both present with a holosystolic murmur

Question 18

Free wall rupture most often occurs from occlusion of ____________.

Answer 18

the LAD (like how the guy with the lute that has a hole in it is on the left of the jester with the coronary hat)

Question 19

Free wall rupture leads to _______________.

Answer 19

tamponade (like the lute case full of milk)

Question 20

What happens to heart tissue during the post-14 day window after an MI?

Answer 20

Deposition of collagen (like the knight wearing tough armor positioned to the right of the half-moon)

Question 21

What are complications of the collagenous phase post-MI?

Answer 21

• Arrhythmia (like the knight holding up the shaking jester with the quivering heart accordion)
• Heart failure (heart balloon beneath jester)
• Dressler syndrome (crossdresser)
• Ventricular wall aneurysm (like the woman who fell into the tent by the moons –she made a depression in it)

Question 22

_________________ can occur months to years after an MI.

Answer 22

Dressler’s syndrome –autoimmune pericarditis that affects the entire heart

(Think of the cross-DRESSER with the guitar case running away past the moon banners.)

Question 23

What causes Dressler syndrome?

Answer 23

Autoantibodies against the heart (like the archers shooting the crossdresser)

Question 24

Ventricular aneurysms can cause _____________.

Answer 24

emboli (like the birds pooping black dots on the girl near the crumpled tent)