Cardiac

Question 1

Blood supply to the SA node?

Answer 1

R coronary artery

Question 2

Blood supply to the AV node?

Answer 2

R coronary artery

Question 3

Obstructive CAD in order of frequency?

Answer 3

(L) Coronary
(R) coronary
(L) LAD
circumflex

Question 4

What level of obstruction is clinically relevant?

Answer 4

Obstruction of a coronary artery has to be > 75% cross-sectional area to be physiologically significant.

Question 5

What is the definite survival improvement for CABG?

two options

Answer 5

Definite improvement in survival is for 3 vessel disease and for left main disease

Question 6

MI complications requiring surgery?

Answer 6

a. Ventricular rupture
b. Acute septal rupture with VSD, left to right shunting
c. Papillary muscle rupture with acute mitral insufficiency
d. Ventricular aneurysm (late effect)

Question 7

Complications of CABG?

Answer 7

a. Cardiac tamponade
b. Tension pneumothorax
c. Atelectasis
d. Phrenic nerve paralysis (? related to cold slush)
e. Sternal wound infections
f. Pancreatitis

Question 8

What is mortality and graft patency (Saphenous v IMA) for CABG?

Answer 8

g. Expected mortality of good risk patients < 4%
1) 10 year Graft patency:
Saphenous vein 50%
Internal mammary @ 10 yrs 85%

Question 9

Indications for pacemaker?

Answer 9

medically refractory Sick sinus syndrome
2nd and 3rd degree heart block (Mobitz II)
Symptomatic bradycardias
Best results with dual chamber pacemakers

Question 10

What is an absolute contraindication to dual chamber pacing?

Answer 10

atrial fibrillation

Question 11

How do you insert a pacemaker?

Answer 11

insert electrodes via subclavian (either side)
Insertion requires testing for threshold of stimulation – satisfactory range is about 0.5-1.5 volts, 0.5-1.5 mamp for atrium as well as testing for satisfactory sensing in atrium, 1-3 millivolts, and 4-12 millivolts in ventricle

Question 12

How does an IABP work?

Answer 12

Balloon placed into thoracic aorta deflates during systole, inflates during diastole “diastolic augmentation.”

Question 13

What are indications for an IABP?

Answer 13

Cardiac shock

a. To stabilize unstable angina patient preop or preangioplasty
b. To support postop low output syndrome (post-CABG) c. To support patient with post MI VSD or papillary muscle rupture
d. To support preop cardiac transplant patient briefly (VAD is better).
e. To support patients at high risk for MI requiring emergent noncardiac operations

Question 14

What are complications of a IABP?

Answer 14

a. Arterial insertion site injury - subintimal dissection
b. Distal embolization or occlusion
c. Local infection, aneurysm formation

Question 15

When does aortic stenosis require valve replacement?

Answer 15

cross section < 1 CM2

or pressure gradient Ao valve > 50 mm Hg

Question 16

What volume of blood can cause pericardial tamponade?

Answer 16

just 100cc if acute.

Question 17

What can cause false results of pericardiocentesis?

Answer 17

Pericardiocentesis may give false negative if blood is clotted, false positive if cardiac chamber aspirated

Question 18

How long can you go on cardiac bypass?

Answer 18

2-4 hours with myocardial protection

Question 19

Major acute complication of going on bypass?

Answer 19

air embolism

Question 20

What are Swann findings in cardiac tamponade?

Answer 20

“Equalization of pressures” — (R) and (L) atrium, RV diastolic and PA diastolic is diagnostic of cardiac tamponade.

Question 21

What are the symptoms and treatment of post-pericardiotomy syndrome?

Answer 21

“Equalization of pressures” — (R) and (L) atrium, RV diastolic and PA diastolic is diagnostic of cardiac tamponade.

Question 22

What are indications and outcomes for ED thoracotomy?

Answer 22

Open cardiac massage for cardiac arrest with thoracic aortic clamping, is useful following blunt and penetrating chest injuries, but is rarely successful following blunt abdominal trauma, and those resuscitated successfully from a cardiac viewpoint have dismal overall outcomes.

Question 23

Treatment of a PDA:
Medical?
Endoluminal?
Surgical?

Answer 23

1. Indomethacin
2. Transcatheter ablation
3. clipping, ligation or division.

Question 24

Treatment for Coarctation of the Aorta?

Answer 24

Can be managed by balloon dilatation, but surgical resection with primary end to end anastomosis is the standard treatment

Question 25

Location of coarctation of the aorta?

Answer 25

Typically at the site of the obliterated ductus arteriosus. Remember neonate has patent ductus, and early post- delivery femoral pulses may be present with flow from ductus

Question 26

Indication and operation for an atrial septal defect?

Answer 26

Operation advised if pulmonary flow is 1.5 X the systemic flow.
Closure is by primary suture or patch.
Care to avoid obstruction of pulmonary vein orifices

Question 27

What are the four features of Tetrology of Fallot?

Answer 27

VSD
RV outflow obstruction
Over-riding aorta
RV hypertrophy

Question 28

What is historic and current repair of Tetrology of Fallot?

Answer 28

Formerly treated with BlalockTaussig shunts (subclavian to pulmonary artery shunting – creating an “artificial PDA”
now treated by complete repair 3-6 months of age

Question 29

What is historic and current repair of Tetrology of Fallot?

Answer 29

Formerly treated with BlalockTaussig shunts (subclavian to pulmonary artery shunting – creating an “artificial PDA for L -> R shunt”
now treated by complete repair 3-6 months of age