Cardiology

Question 1

What drug toxicity can be counteracted by Mg?
• what arrhythmia can be counteracted?

Answer 1

Digoxin Drug Toxicity can be counteracted Torsades de points can be counteracted

Question 2

What is the use in adenosine as an anti-arrhythmic (aka conditions its used for)?
• what is its MOA?
• Adverse effects?

Answer 2

Adenosine:
• Used for SVT (very short acting)

MOA:
• Causes K+ efflux and hyperpolarizes cells while reducing the activity of the immediate Ca channels

Adverse effects;
• Flushing, Hypotension, Chest pain, Impending Doom, and Bronchospasm

Question 3

Classic Triad of Henoch-Scholein Purpura

Answer 3

Follows URL then:
• Palpable Purpura on butt and legs

• Arthralgia
• GI pain

Vasculitis and Nephropathy (Berger dz) = IgA mediated

Question 4

How does an occlusion of the RIGHT coronary artery appear on ECG?
• what leads show these changes?

Answer 4

ST elevation in leads II, III, and aVF

• remember these are the inferior leads this makes sense because the RCA gives off the posterior descending artery that supplies the posterior, inferior ventricles and the posterior 1/3 of the IV septum

Question 5

What does it mean to have right dominant circulation?
• is this common?

Answer 5

In all People:
• RCA gives of the SA nodal branch, Marginal Artery, and AV nodal branch

In 80% of people:
• RCA also gives off the posterior descending artery that supplies the inferior ventricles and the posterior 1/3 of the IV septum

Question 6

How do funny Na+ channels work to cause the pacemaker Action Potential?

Answer 6

Normal Na+ channels
• Open at More positive threshold potential to allow influx of ions and increase depolarization (more positive charge) of the myocyte

Funny Na+ channels
• Open when the potential gets really negative and leak in ions that will then bring Calcium Channels up to the threshold potential leading to myocyte depolarization

Question 7

What are some causes of dilated Cardiomyopathy?

Answer 7

ABCCCD
• Alcohol Abuse
• we Beriberi
• Coxsackie B viral myocarditis
• Cocaine use
• Chagas disease
• Doxorubicin

Question 8

In what layer do you see plaques in atherosclerosis?

Answer 8

Intima (note: this layer is also affected in temporal arteritis but you expect to see mononuclear infiltrate)

Question 9

What are two different ways to calculate Cardiac Output?

Answer 9

CO = SV x HR

CO = Rate of Oxygen Consumption / (arterial oxygen - venous oxygen)

Question 10

How is stroke volume calculated?

Answer 10

SV = EDV - ESV

Question 11

What parts of the adult heart are derived from the:

• Trucus Arteriosus
• Bulbus cordis
• Endocardial cushion
• Primative Atrium

Answer 11

Trucus Arteriosus:
- Ascending Aorta and Pulmonary Trunk

Bulbus Cordis:
- Smooth Outflow Tracts of the L and R ventricles

Endocardial Cushion:
- Atrial Septum, Membranous IV septum, AV and Semilunar valves

Primative Atrium:
- Trabeculated part of the L and R atria

Question 12

What parts of the adult heart are derived from the:

• Primative Ventricle
• Primitive Pulmonary Vein
• Left horn sinus venosus
• Right Horn of Sinus Venosus

Answer 12

Primative Ventricle:
- Trabeculated part of the L and R ventricles

Primitive Pumonary Vein:
- Smooth part of the Left Atrium

Left horn of sinus venosus:
- Coronary Sinus

Right Horn of SInus Venosus:
- Smooth part of the right atrium (sinus venarum)

Question 13

What primative heart structure gives rise to the SVC?

Answer 13

Right common cardinal Vein and Right anterior Cardinal Vein