Ch. 2 CV Emergencies Flashcards
What is the biggest risk factor for PAD?
atherosclerosis
which is due to factors including cigarette smoking, HLD, HTN, and DM
What is Leriche Syndrome?
Triad of
1. bilateral hip claudication,
2. erectile dysfunction,
3. absent femoral pulses
= aortoiliac occlusive disease
What ABI is diagnostic of PAD?
ABI <0.9
At what ABI does claudication typically occur?
ABI <0.6
At what ABI does resting angina typically occur?
<0.26
What is initial treatment for PAD?
Risk-factor modification: Smoking cessation, antihypertensive therapy, lipid-lowering therapy, glycemic control
Antithrombotic therapy (aspirin, clopidogrel, warfarin)
What is the only effective therapy for Buerger Disease?
Smoking cessation
What is the pathophysiology behind a true arterial aneurysm?
Constant shear stress at the vessel wall
contributes to weakening of the media and, eventually, dilation or “ballooning” of all 3 vessel wall layers
What is a pseudoaneurysm?
Disruption of the intima and media; only thin adventitia remains intact
What is the most common location of aortic aneurysms and what type of aneurysm are they?
infrarenal; usually true aneurysms
What diameter defines a AAA?
> 3 cm
What are primary risk factors for AAA?
first-degree relative with AAA,
co-morbid coronary artery disease (CAD) or occlusive PVD,
older age (mean age at diagnosis is 65-70 years), and
smoking history
Where is the most common location of AAA rupture?
retroperitoneal
What is the imaging modality of choice for ruptured AAA in unstable patient?
bedside ultrasound
What is blue toe syndrome?
atherosclerotic aneurysms can cause atheroembolism, in which microemboli travel to and obstruct distal small vessels
What is a acute possible complication of AAA endovascular grafting?
vascular injury to the renal, mesenteric, or Adamkiewicz artery (the latter causes an anterior cord syndrome)
How is a thoracic aortic aneurysm defined?
diameter >4.5 cm
How is expanding/ruptured thoracic aortic aneurysm diagnosed in unstable patient?
Transesophageal echocardiography (TEE)
How is expanding/ruptured thoracic aortic aneurysm diagnosed in unstable patient?
CT Chest
What is the treatment for unstable patient with Thoracic aortic aneurysm?
Same as dissection – resuscitation, aggressive Bp and HR control, and immediate surgical consultation
What is the most common risk factor for aortic dissection?
Uncontrolled HTN
What is the pathophys of aortic dissections?
Disruption of intima of aortic wall → blood travels (dissects) into media, creating false lumen
What lab test has good sensitivity for dissection and therefore can be used to rule out dissection?
d-dimer
What are the two most common ECG findings in aortic dissections?
- LVH
- inferior/posterior ischemia indicating RCA involvement
What is the diagnostic test of choice for aortic dissection?
CT Angiogram
What are the HR and BP goals for aortic dissection?
SBP 100-120 mmHg
HR <60 BPM
What medications are used for HR and BP control in aortic dissection?
Use IV Bblockers such as esmolol or labetalol
if severe asthma or COPD –> metoprolol or atenolol
Can add nitroprusside for additional control
Acute arterial occlusion is most commonly caused by ____ (thromboembolism or thrombotic occlusion?)
thromboembolism
What is the most common site of acute arterial embolism?
Bifurcation of common femoral A.
What are the 6 Ps of life-threatening ischemia?
Pain
Pallor
Pulselessness
Paralysis
Paresthesias
Poikilothermia
Why is it important to differentiate thromboembolic from thrombotic causes of acute limb ischemia?
treated differently:
Acute thromboembolism: heparin + Fogarty catheter embolectomy
Thrombosis with limb-threatening ischemia: Heparin + embolectomy + bypass grafting
Arterial thrombosis without limb-threatening ischemia: heparinization ± thrombolysis
What is Virchows Triad?
Damage to the vessel wall,
venostasis, or
hypercoagulable state
What is Wells Criteria for DVT?
■ Score ≤ 2 indicates a low or moderate pretest risk for DVT.
■ Score > 2 indicates a high pretest risk for DVT.
Active cancer 1
Paralysis/immobilization 1
Bedridden 3 d/surgery in last 4 wk 1
Tender along deep vein (localized) 1
Entire leg swollen 1
Unilateral calf swelling (> 3 cm) 1
Pitting edema, 1 leg 1
Collateral superficial nonvaricose vein 1
Previous documented DVT 1
Alternative diagnosis likely −2
What is the half life of d-dimer?
8 hours
When may the d-dimer be elevated (other than DVT/PE)?
sepsis, pregnancy, trauma, MI, liver disease,
cancer
What is the most common cause of PE?
DVT
Which symptoms has strongest association with PE?
Hemoptysis
What is the most common complaint in PE?
dyspnea
What is the most common physical exam finding in PE?
tachypnea
What do you call a Pleural-based, wedge-shaped density indicating infarcted lung on CXR?
Hampton hump
What do you call the rare sign on CXR showing ↓ vessel markings distal to embolus (oligemia)?
Westermark sign
What 7 clinical features are included in Wells PE prediction tool?
Clinical symptoms of DVT 3
Other diagnosis less likely than PE 3
Heart rate > 100 bpm 1.5
Immobilization or surgery within past 4 wk 1.5
Previous DVT or PE 1.5
Hemoptysis 1
Malignancy 1
What Wells score = high risk for PE?
> 6 points
What Wells score = moderate risk?
2-6 points
Whats included in PERC rule?
Low pretest probability for PE by the treating clinician’s estimate, plus:
Age < 50 y
Pulse < 100 bpm
Oxygen saturation > 94%
No hemoptysis
No unilateral leg swelling
No recent major surgery or trauma
No prior PE or DVT
No hormone use
What is the treatment for PE?
Immediate anticoagulation with unfractionated heparin infusion or
LMW heparin.
What should be used to treat PE if heparin and LMWH are contraindicated?
Factor Xa inhibitor, fondaparinux
What are indications for thrombolysis in PE?
hypotension (SBP < 90 mm Hg for > 15 minutes or baseline SBP reduction > 60 mm Hg), severe hypoxemia, cardiac
arrest, evidence of right heart strain on
echocardiogram
What is the preferred agent and dosing for thrombolysis in massive PE?
tPA is preferred agent (100 mg over 2 hours)
What is the most common cause of venous insufficiency?
DVT
What is the law of appropriate discordance?
The T waves should be deflected in
the direction opposite to the terminal
deflection of the rR′ or rSR′ complexes
What ECG findings are seen in hypercalcemia?
■ Shortened QT intervals (classic finding)
■ Depressed and shortened ST segments
■ Widened T waves
What ECG findings are seen in hypocalcemia?
■ Hallmark = QT prolongation
■ Due to lengthening of the ST segment
■ Occurs with Ca+ < 6.0 mg/dL
What are common ECG findings in those on Digitalis?
■ Depressed (scooped or sagging) ST segments
■ Shortened QT intervals
■ Flattened T waves
■ Prominent U waves
In Digitalis toxicity, when should you give Digoxin antibody?
Hyperkalemia;
avoid routine use of calcium
What ECG findings are seen in Digitalis toxicity?
■ Any dysrhythmia is possible (especially premature ventricular contractions
[PVCs], atrial tachyarrhythmias with AV block, bradycardia).
■ Slow, regular atrial fibrillation.
■ Bidirectional ventricular tachycardia.
What ECG findings are seen with hypothermia?
Cardiac conduction abnormalities result in prolongation of all cardiac intervals.
Typical progression from sinus bradycardia to atrial fibrillation to ventricular
fibrillation.
Osborn (or J) waves at end of QRS complex.
■ Characteristic but can be seen in other heart conditions
What is the most common cause of systolic cardiac dysfunction?
ischemic heart disease
What is the most common cause of diastolic cardiac dysfunction?
HTN
What is the mechanism of action of nitroglycerin?
↓ Preload by venodilation, ↓ afterload (at high doses) via arterial vasodilation, direct coronary vasodilator (good in ischemia)
What two electrolyte disturbances can be caused by Furosemide?
Hypokalemia, hypomagnesemia
What is the mechanism of action of nitroprusside?
More potent arterial vasodilator than NTG, ↓ afterload, ↓ preload via venodilator effect, may dilate normal coronaries more
than diseased → coronary steal syndrome
