Damjanove Chapter 4

Question 1

Zone at risk for hypoxia in the heart?

Answer 1

Subendocardial myocardium: beyond supply zone from ventricles and is last to receive blood from coronary arteries (first area to become ischemic if BP drops)

Question 2

Paradoxical infarcts are due to

Answer 2

anastomoses due to gradual narrowing of the coronary artery that normally provides blood to the infarcted area (left coronary artery supply zone infarct due to thrombus on RCA or vice versa)

Question 3

Vagal stimulation has a

Answer 3

negative chronotropic and inotropic effect, slowing down the heartbeat and reduces strength of cardiac contraction

Question 4

Digitalis and cardiac glycosides

Answer 4

increase the concentration of Ca in cardiac myocytes, thus stimulating heart contraction

Question 5

Preload refers to the; energy of contraction proportional to

Answer 5

end-diastolic volume (contraction of ventricles increases in proportion to increased preload, or Frank-Starling law);
initial length of cardiac muscles

Question 6

Afterload refers to

Answer 6

pressure and resistance against which ventricles work;

Question 7

Diastasis is

Answer 7

pressure of ventricles reaching atria pressure;

Question 8

Phases of heart beginning with first heart sound

Answer 8

1. first heart sound (closure of AV valves)
2. Isovolumic contraction
3. Aortic valve opens and ejection phase
4. Aortic valve closes
5. Isovolumic relaxation
6. Closure of aortic valve (second heart sound)
7. Rapid filling phase of diastole
8. Repeat

Question 9

Palpitation can be associated with

Answer 9

1. a fib (heartbeats rapid and irregular)
2. supraventricular or ventricular tachy: heartbeats are rapid and regular
3. premature atrial and ventricular contractions: skipped beats

Question 10

Cardiac dyspnea can manifest as

Answer 10

1. high output
2. normal output: obesity
3. low output: CHF, MI, valvular diseases, pericarditis

Question 11

Pulmonary edema is a sign of; peripheral edema is a sign of

Answer 11

left heart failure (MI or CHF); right heart failure (see chronic passive congestion, congestive HSM)

Question 12

Cyanosis and its two forms:

Answer 12

arterial sat is s, venous or arterial thrombi, emboli

Question 13

Causes of syncope

Answer 13

ORTHOstatic:

1. Orthostatic (drugs like methyldopa or guanethidine; can be hyperadrenergic or hypoadrenergic)
2. reflex-related (coughing, straining as you shit, exercise)
3. TIA/seizure/epilepsy
4. Heart conditions (obstruction of blood flow by valvular heart disease or atrial myxoma; conduction disorders)
5. Other

Question 14

Anacrotic pulse typical of; pulsus bisferiens occurs in; pulsus paradoxus seen in

Answer 14

aortic stenosis; aortic regurg; cardiac tamponade and constrictive pericarditis

Question 15

a wave produced by; c results from; v wave occurs

Answer 15

Atrial contraction; bulging of tricuspid Cusps into RA; during end of ventricular Systole and early phase of ventricular diastole

Question 16

No a wave is; increased a wave with impaired y descent is;

Answer 16

a fib; triscupid stenosis

Question 17

Hyperkalemia makes the T wave

Answer 17

symmetrically peaked, whereas hypokalemia leads to ST segment depression and flattening of T waves with appearance of terminal U wave

Question 18

Doppler echo used for evaluation of

Answer 18

possible cardiomyopathy

Question 19

Some example of cardiac markers:

Answer 19

1. myoglobin (marker for early myocardial cell necrosis)
2. CK (MB isoenzyme found predominantly in the heart)
3. Troponins (T links troponin complex to tropomyosin; I inhibits actomyosin ATPase; C binds clacium and regulates actin contraction)
4. LDH (LDH1 of cardiac origin; look for LDH1:LDH2 ratio of >1 for MI)

Question 20

MI changes on ECG include:

Answer 20

1. T wave inversion
2. ST segment elevation
3. Changes in width and shape of QRS complex
4. Progressively deepening Q wave

Question 21

MI caused by occlusion of RCA typically leads to

Answer 21

sinus bradycardia or AV nodal block; R and L BBB’s occur in patients with anterior MI due to occlusion of LAD

Question 22

Immunologic pericarditis is

Answer 22

Dressler’s syndrome: patient develops precordial pericarditic pain, pericardial friction rub, and pericardial effusion (responds well to steroid treatment)

Question 23

Orthodromic tachy has; antidromic tachy has

Answer 23

impulses passing normally through the AV node and reentering atrium through an accessory pathway;
impulses entering ventricle through accessory pathway but reentering atrium through AV node;

Question 24

atrial flutter facts:

Answer 24

1. atrial contraction rate of 220-400 b/min
2. AV block at rate of 2:1 (ventricular contraction rate always less prominent)
3. ECG with typical saw-tooth pattern

Question 25

V tachy requires treatment with

Answer 25

antiarrhythmic drugs and DC cardioversion

Question 26

acute mitral regurg occurs most often due to

Answer 26

rupture of papillary muscle in MI or due to rupture of chordae tendineae in infective endocarditis

Question 27

Most common cause of restrictive cardiomyopathy is

Answer 27

amyloidosis!!!