Cardiology Flashcards
What elements of the history and physical steer you away from a diagnosis of MI?
Wrong age (under 40 without known heart disease, family history) Lack of risk factors Physical characteristics of pain (reproducible by palpation? sharp? well-localized? related to eating?)
What findings on EKG should make you suspect an MI?
Flipped or flattened T waves, ST-segment elevation (depression means ischemia; elevation means injury) and/or Q waves in segmental distribution
Describe the classic pattern of chest pain in an MI
Classically crushing or pressure sensation; poorly localized substernal pain that may radiate to the shoulder, arm, or jaw
Usually NOT reproducible on palpation and does not resolve with nitroglycerin (as it does in angina)
Lasts at least half an hour
What tests are used to diagnose an MI?
EKG, CK-MB, troponin I or T, or myoglobin (usually drawn Q8 3x before MI is ruled out)
Elevated LDH uncommonly used for late MI presentation (troponin stays elevated more than 24 hrs)
AST can be elevated but not used clinically
Radiographs - cardiomegaly +/- pulmonary congestion
Echo - ventricular wall motion abnormalities
Describe the classic physical exam findings in patients with MI
Diaphoretic, anxious, tachycardic, tachypneic, pale, may have nausea/vomiting
Large heart attacks causing HF: bilateral pulmonary rales, distended neck veins, S3 or S4 heart sound, new murmurs, hypotension, +/- shock
What historical points should steer you toward a diagnosis of MI?
History of angina or previous chest pain, murmurs, arrhythmias, risk factors for CAD, HTN, diabetes
What medications do you administer for an MI?
Morphine (pain control) Aspirin Nitroglycerin Beta blocker (reduce mortality rate of MI and incidence of second MI) Clopidogrel Unfractionated or LMW heparin ACEI or ARBC within 24 hrs HMG-Coa reductase inhibitor
When is reperfusion therapy indicated for an MI?
Reperfusion is indicated if the time from onset of symptoms is less than 12 hours. Early reperfusion (less than 4-6 hrs) is preferred to try to salvage myocardium.
Can be accomplished by fibrinolysis or percutaneous coronary intervention (i.e. balloon angioplasty/stent), coronary artery bypass grafting may be required.
True or false: With good management, patients with an MI will not die in the hospital.
False. Even with the best management, patients may die from an MI. May also have a second MI during hospitalization. Watch for sudden deterioration!
When is heparin indicated in the setting of chest pain and MI?
Heparin should be started if unstable angina is diagnosed, if the patient has a cardiac thrombus, or if severe congestive HF is seen on echo.
Do NOT give heparin to patients with contraindications to use (e.g. active bleeding)
What clues suggest GERD/peptic ulcer rather than MI chest pain?
Relation to certain foods (spicy, chocolate), smoking, caffeine, or lying down
Pain relieved by antacids or acid-reducing meds
Positive H. pylori test
What clues suggest chest wall (e.g. costochondritis, bruised or broken ribs) rather than MI chest pain?
Pain is well localized and reproducible on chest wall palpation
What clues suggest esophageal problems (e.g. achalasia, nutcracker esophagus, spasm) rather than MI chest pain?
Difficult differential!
Negative MI work-up or lack of atherosclerosis risk factors
Barium swallow abnormalities or esophageal manometry
What clues suggest pericarditis rather than MI chest pain?
Viral URI prodrome
EKG with diffuse ST-segment elevation, ESR elevated, low-grade fever
Pain relieved by sitting forward!
Most common cause is coxsackievirus (but also consider TB, uremia, malignancy, SLE)
What clues suggest pneumonia rather than MI chest pain?
Chest pain is due to pleuritis
Patients also have cough, fever, +/- sputum production
Ask about sick contacts
What clues suggest aortic dissection rather than MI chest pain?
Associated with severe tearing or ripping pain that may radiate to the back
Look for HTN or evidence of Marfanโs (tall, thin, hyperextensible joints)
Blunt chest trauma can cause aortic laceration and pseudoaneurysm
How can you recognize stable angina?
Begins with exertion or stress and remits with rest or calming down. Described as pressure or squeezing pain in substernal area and may radiate to shoulders, neck, and/or jaw.
Often accompanied by SOB, diaphoresis, +/- nausea. Usually relieved by nitroglycerin.
EKG - ST-segment depression during acute attack, otherwise normal
Pain lasts less than 20 minutes
Define unstable angina
Change from previously stable angina. If pt used to experience angina once a week and now has it once a day, technically that is unstable angina.
EKG shows ST depression, minimally elevated cardiac enzymes, prolonged chest pain that does not respond to nitro initially. Pain often begins at rest.
How do you treat unstable angina?
Similar to MI
O2, aspirin, nitro, beta-blocker, clopidogrel, heparin, glycoprotein IIb/IIIa receptor inhibitor, ACEI or ARB
Consider emergent PTCA if pain does not resolve
Describe variant (Prinzmetal angina)
Pain at rest (unrelated to exertion) and ST elevation; cardiac enzymes are normal.
Cause is coronary spasm.
Usually responds to nitro and it treated long-term with calcium channel blockers (reduce arterial spasm)
Define silent MI. How common is it?
Patients with silent MI do not develop chest pain
Present with CHF, shock, or confusion and delirium (esp. elderly patients)
Up to 25% of cases (esp. in diabetics with neuropathy)
What physical exam findings are associated with mitral stenosis?
Late diastolic blowing murmur (best heart at apex)
Opening snap, loud S1, a. fib, L atrial enlargement, pulmonary HTN
What physical exam findings are associated with mitral regurgitation?
Holosystolic murmur (radiates to axilla) Soft S1, L atrial enlargement, L ventricular hypertrophy, pulmonary HTN
What physical exam findings are associated with aortic stenosis?
Harsh systolic ejection murmur (best heard in aortic area, radiates to carotids)
Slow pulse upstroke, S3/S4, ejection click, L ventricular hypertrophy, cardiomegaly
*syncope, angina, HF
What physical exam findings are associated with aortic regurgitation?
Early diastolic decrescendo murmur (best heard at apex)
Widened pulse pressure, L ventricular hypertrophy, L ventricular dilatation, S3
What physical exam findings are associated with mitral prolapse?
Midsystolic click, late systolic murmur
*panic disorder
Who should receive endocarditis prophylaxis?
Cardiac conditions for which prophylaxis with dental procedures is recommended includes prosthetic cardiac valve, previous infectious endocarditis, congenital heart disease, and cardiac transplant recipients who develop valvulopathy
No longer recommended for GU or GI procedures.
Describe the protocols for endocarditis prophylaxis
Should be administered in single dose before procedure. Amoxicillin is preferred choice for oral therapy.
Cephalexin, clindamycin, azithromycin, or clarithromycin may be used for penicillin allergies.
Ampicillin, cefazolin, ceftriaxone, or clindamycin may be used if unable to take orals.
What is Virchowโs triad?
3 findings associated with DVT:
- endothelial damage
- venous stasis
- hypercoagulable state
Common clinical scenarios for development of DVT
Surgery (esp. orthopedic, pelvic, abdominal, or neurosurgery), malignancy, trauma, immobilization, pregnancy, birth control pills, DIC, thrombophilias
Describe the physical signs and symptoms of DVT. How is it diagnosed?
Unilateral leg swelling, pain or tenderness, +/- Homan sign (pain on dorsiflexion, present in 30%)
Best diagnosed by compression ultrasonography or impedance plethysmography of veins of extremity. Gold standard is venography but this is invasive, reserved for situations in which diagnosis is not clear.
True or false: Superficial thrombophlebitis is a risk factor for pulmonary embolus.
False. Superficial thrombophlebitis (erythema, tenderness, edema, palpable clot in superficial vein) affect superficial veins and does not cause PEs. It is considered a benign condition though if recurrent can be marker of malignancy (e.g. Trousseau syndrome - migratory thrombophlebitis - is classic marker for pancreatic cancer)
How should you treat patients with superficial thrombophlebitis?
NSAIDs and warm compresses
How is DVT treated? For how long?
Systemic anticoagulation is necessary. Use IV heparin or subcutaneous LMW heparin initially, followed by crossover to oral warfarin. Should be maintained on warfarin for at least 3-6 months - possibly for life if more than one episode of clotting occurs.