Cardiology I Flashcards
Xarelto
rivaroxaban
What is the mechanism of rivaroxaban
Selectively blocks active site of factor Xa, inhibiting blood coagulation
What is the blackbox warning associated with Xarelto
TX Discontinuation: increase risk of thrombotic event and stroke when D/C rivaroxaban in pts with non valvular atrial fibrillation: if must D/C rivraoxaban for reasons other than pathological bleeding, consider administering another anticoagulant.
Pradaxa
Dabigitran etexilate
What is the mechanism of dabigitran
directly, reversibly inhibits thrombin
What are the two ways to cardiovert a patient
- Chemically
2. Electrically
Where are 90% of cardiac blood clots formed
atrial appendage
Is removal of the atrial appendage a viable surgical treatment for Afib
Not as the sole means of indication to surgery; will only assist in thromboembolic event but will not affect rate or rhythm
Tikosyn
dofetilide
Considered to be the best antiarrhythmic
When is tikosyn indicated
Atrial fibriliation flutter
What is the mechanism of dofetilide
prolongs action potential phase 3 (class III antiarrhythmic)
Where do the foci for afib typically originate
close proximity to the pulmonary veins
What are the surgical treatment options for Afib
- Endocardial abblation: circular ablation around the pulmonary veins. Lower outcome success
- Maze procedure: epicardial abblation. Numerous incisions leading to scar formation
- Hybrid: epicardial and endocardial abblation. Still considered to be experimental and limited data available on the success rate.
What are the limiting factors for anticoagulants other than heparin and warfarin
renal clearance
What is cardiac FFR
(FFR) is a technique used in coronary catheterization to measure pressure differences across a coronary artery stenosis (narrowing, usually due to atherosclerosis) to determine the likelihood that the stenosis impedes oxygen delivery to the heart muscle (myocardial ischemia).[1]
Fractional flow reserve is defined as the pressure behind (distal to) a stenosis relative to the pressure before the stenosis. The result is an absolute number; an FFR of 0.50 means that a given stenosis causes a 50% drop in blood pressure. In other words, FFR expresses the maximal flow down a vessel in the presence of a stenosis compared to the maximal flow in the hypothetical absence of the stenosis.
What is IVUS
intravascular ultrasound
a medical imaging methodology using a specially designed catheter with a miniaturized ultrasound probe attached to the distal end of the catheter. The proximal end of the catheter is attached to computerized ultrasound equipment. It allows the application of ultrasound technology to see from inside blood vessels out through the surrounding blood column, visualizing the endothelium (inner wall) of blood vessels in living individuals.
Plavix
clopidogrel
What is the mechanism for clopidogrel
Irreversibly binds to P2Y12 adenosine diphosphate receptors, reducing platelet activation and aggregation
What are the indications for clopidogrel
Acute coronary syndrome
Thrombotic event prevention
What are bare metal stents
a vascular stent without a coating (as used in drug-eluting stents). It is a mesh-like tube of thin wire. The first stents licenced for use in cardiac arteries were bare metal - often 316L stainless steel. More recent (‘2nd generation’) stents use cobalt chromium alloy.
What are the types of exercise stress types
- Bruce
- Cornell
- Naughton
Discuss the bruce protocol
The Bruce protocol is generally preferred for office-based exercise testing largely because it has been carefully validated [14]. The protocol is divided into successive three minute stages, each of which requires the patient to walk faster and at a steeper grade. Stage I has at an incline of 10 percent and a speed of 1.7 miles per hours; stage II progresses to an incline of 12 percent and a speed of 2.5 miles per hour (table 8). The determinants of the end of the protocol are discussed below. (See ‘Test endpoints’ below.)
The initial work load in stage I may occur too suddenly for some individuals, and an optional stage 1/2, in which the work load is lower than the usual first stage of the Bruce protocol, may be added at the beginning.
The modified Bruce protocol can be used for risk stratification of patients after an acute coronary syndrome (myocardial infarction or unstable angina) and in sedentary patients in whom the standard Bruce protocol may be too strenuous. The modified protocol adds two low-workload stages, both of which require less effort than Stage 1, to the beginning of the standard Bruce protocol.
Discuss the cornell protocol
The Cornell protocol was developed for use with computerized ST/HR slope determination, a possibly improved method of quantitative exercise electrocardiography [15,16]. The ACC/AHA guidelines concluded that the ST/HR slope (the rate-related change in exercise-induced ST segment depression) has not yet been validated, but that it could prove useful in patients with borderline or equivocal ST responses, such as ST segment depression associated with a very high exercise heart rate [2].
In the Cornell protocol, each stage of the Bruce protocol is divided into two smaller and shorter stages. Although this was done to provide more data points for the computerized ECG analyses, the protocol is also more applicable to patients with limited exercise tolerance because of the smaller workload increments.
Discuss the naughton protocol
The Naughton protocol is often used in post-MI exercise testing to classify patients into high-risk and low-risk categories and to determine optimal treatment strategies [17]. This protocol is also used for functional exercise testing with gas analysis techniques to measure oxygen uptake and VO2max. (See “Functional exercise testing: Ventilatory gas analysis” and “Exercise capacity and VO2 in heart failure”.)
In patients who have not been completely revascularized, two different protocols have been commonly used:
A predischarge submaximal test (modified Bruce or Naughton protocol). The 2004 ACC/AHA guidelines on ST elevation MI suggested that such testing can be performed as early as three to five days in patients without complications [18]. No changes to this approach were made in the ACC/AHA 2007 focused update [19].
A traditional symptom-limited exercise test, in which the test is not terminated for a target heart rate. The 2004 ACC/AHA guidelines for the management of ST elevation MI concluded that such testing is appropriate at five days or later [18] and the 2007 guidelines of unstable angina and non-ST elevation MI recommended testing at three to five days [20]
Name the loop diuretics
Bumetanide
torsemide
ethacrynic acid
furosemide
bumex
bumetanide
What is the mechanism of metazolone
inhibits cortical diluting site and proximal convoluted tubule sodium resorption
demadex
torsemide
lasix
furosemide
Betapace
sotalol
What is the mechanism of sotalol
non-selectively antagonizes beta-1 and beta-2 adrenergic receptors; prolongs action potential phase 3 (class III antiarrhythmic)
What testing is available for patients with palpitations
- EKG
- Echo
- Holter or Event monitor
What is the difference between a holter and an event monitor
Holter Monitor is worn continuously for 48 hours and can not be taken off.
Event monitor is worn for 14-28 days and only records the events when the patient activates the monitor
Is the bell of a stethoscope better at detecting low or high frequency sounds?
Lower frequency
What is corrigans pulse
bounding carotid pulse.
Often coincides with Watson’s waterhammer pulse
what is mueller’s sign
pulsation of the uvula. Seen with severe aortic insufficiency
What is an austin flint murmur
a low-pitched rumbling heart murmur which is best heard at the cardiac apex.[1] It can be a mid-diastolic[2] or presystolic murmur[3] It is associated with severe aortic regurgitation.
Classically, it is described as being the result of mitral valve leaftlet displacement and turbulent mixing of antegrade mitral flow and retrograde aortic flow:[7]
Displacement: The blood jets from the aortic regurgitation strike the anterior leaflet of the mitral valve, which often results in premature closure of the mitral leaflets. This can be mistaken for mitral stenosis.
Turbulence of the two columns of blood: Blood from left atrium to left ventricle and blood from aorta to left ventricle.
What is de musset’s sign
head bobbing in sync with the heart beat
Duroziez’s sign
a sign of Aortic insufficiency.[1] It consists of an audible diastolic murmur which can be heard over the femoral artery when it is compressed.[2]
What are the common clinical signs of aortic insufficiency
Duroziez's sign De Musset's Sign Austin Flint Murmur Mueller's Sign Corrigan's Sign
What is DES when referring to cardiac cath
drug eluting stent
What is BMS when referring to cardiac cath
Bare metal stent
Myocardial Perfusion Imaging
It evaluates many heart conditions from coronary artery disease (CAD) to hypertrophic cardiomyopathy and myocardial wall motion abnormalities. The function of the myocardium is also evaluated by calculating the left ventricular ejection fraction (LVEF) of the heart. This scan is done in conjunction with a cardiac stress test. While a myocardial perfusion scan can determine with significant accuracy whether a patient has two or fewer coronary arteries which are dangerously occluded, the scan has a major fault in accuracy which is built into it which inevitably results in missed diagnoses of persons who suffer from three-vessel disease, the most serious form of coronary artery occlusion.
Coreg
Carvedilol
What is the mechanism of carvedilol
selectively antagonizes alpha-1 adrenergic receptors; antagonizes beta-1 and beta-2 adrenergic receptors (selective alpha and non-selective beta blocker)
What are the indications of coreg
HTN
CHF
Post MI
What is the role of procalcitonin in sepsis
Elevated procalcitonin levels are associated with bacterial infection and sepsis
Imdur
Isosorbide mononitrate
What is the mechanism isosorbide mono nitrate
Simulates cyclic GMP production, Resulting in Vascular smooth muscle relaxation.
How is lactate used in sepsis
An additional tool, specifically lactate clearance greater than 10% As a target for resuscitation.
What is the results of the courage trial
Silent myocardial ischemia carries a high mortality. primarily treat medically and then surgically if nonresponsive to medicine
Micardis
Telmisartan
What is the mechanism of telmisartan
ARB
Selectively antagonizes angiotensin II AT-1 receptors
What is Fabry’s disease
A lysosomal storage disease.
What is tetralogy Of fallot
a congenital heart defect which is classically understood to involve four anatomical abnormalities overriding AO (although only three of them are always present). It is the most common cyanotic heart defect, and the most common cause of blue baby syndrome
- Pulmonary infundibular stenosis
- Overriding aorta
- VSD
- Right ventricular hypertrophy
What is an MRCP
Magnetic resonance cholangiopancreatography (MRCP) is a medical imaging technique that uses magnetic resonance imaging to visualise the biliary and pancreatic ducts in a non-invasive manner.[1] This procedure can be used to determine if gallstones are lodged in any of the ducts surrounding the gallbladder.
What is an ERCP
Endoscopic retrograde cholangiopancreatography (ERCP) is a technique that combines the use of endoscopy and fluoroscopy to diagnose and treat certain problems of the biliary or pancreatic ductal systems. Through the endoscope, the physician can see the inside of the stomach and duodenum, and inject dyes into the ducts in the biliary tree and pancreas so they can be seen on X-rays.
What is anchoring heuristic
Failing to consider other options. Locking in on a central idea.
What is available heuristic
“Everyone has what everyone has”
a decision maker relies upon knowledge that is readily available rather than examine other alternatives or procedures.
What is pituitary apoplexy
bleeding into or impaired blood supply of the pituitary gland at the base of the brain. This usually occurs in the presence of a tumor of the pituitary, although in 80% of cases this has not been diagnosed previously. The most common initial symptom is a sudden headache, often associated with a rapidly worsening visual field defect or double vision caused by compression of nerves surrounding the gland. This is followed in many cases by acute symptoms caused by lack of secretion of essential hormones, predominantly adrenal insufficiency.
Is a head CT alone adequate to rule out stroke
Nope
What is a scout MRI
A preliminary film taken of a body region before a definitive imaging study–eg, an scout film of the chest before a CT; ‘scouts’ serve to establish a baseline and are used before angiography, CT, MRI
How do you differentiate between MAT, wondering pacemaker and AFIB?
Wandering pacemaker: asymmetrical p waves with variable conduction velocity and a rate less than 100
MAT: asymmetrical p waves with variable conduction velocity and a rate greater than 100
AFIB: no p waves with variable conduction velocity. “irregular irregular”
Name the three irregular rhythms
- Wandering pacemaker
- Multifocal atrial tachycardia
- Atrial fibrillation
Name the the different types of escape rhythms or beats
- Atrial
- Junctional
- Ventricular
Name the premature beats
- Atrial
- Junctional
- Ventricular
What is the mechanism of atenolol
Selectively antagonizes beta-1 receptors
When should palliative care be considered with cancer patients
At the onset of treatment
What is dysmetria
refers to a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is a type of ataxia. It is sometimes described as an inability to judge distance or scale
What are the effects of hypocalcemia
Can be recalled by the mnemonic “CATS go numb”- Convulsions, Arrythmias, Tetany and numbness/parasthesias in hands, feet, around mouth and lips.
What are the effects of hyperkalemia on EKG
With mild to moderate hyperkalemia, there is reduction of the size of the P wave and development of peaked T waves.
Severe hyperkalemia results in a widening of the QRS complex, and the ECG complex can evolve to a sinusoidal shape.
What are the effects of hypocalcemia on EKG
QT interval prolongation
What are the effects of hypercalcemia on EKG
Decrease in the QT interval
What are the causes of hypercalcemia
CHIMPANZEES C = Calcium supplementation H = Hyperparathyroidism I = Iatrogentic (Drugs such as Thiazides, or Immobility after surgery) M = Milk Alkali syndrome P = Paget disease of the bone A = Acromegaly and Addison's Disease N = Neoplasia (common cause) Z = Zolinger-Ellison Syndrome (MEN Type I) E = Excessive Vitamin D E = Excessive Vitamin A S = Sarcoidosis
What is the mechanism of amlodipine
Inhibits calcium ion influx to vascular smooth muscle and myocardium
What is the most common and potentially correctable cause of secondary hypertension
Renovascular disease
10-45% of white patients with severe or malignant HTN have renal artery stenosis
What are common causes of secondary hypertension
Primary kidney disease Primary aldosteronism OCP Pheochromocytoma Cushing's syndrome Sleep apnea Coarctation of the aorta Hypo or hyperthyroidism
What is the classifications of fibromuscular lesion?
Based on their arterial layer
- Medial fibroplasia (80%)
- Intimal fibroplasia (~10%)
- Perimedial fibroplasia
- Medial hyperplasia (rare)
- Periarterial hyperplasia (rare)
What percentage of adults with renovascular HTN have FMD?
10%
What is the gold standard for diagnosing FMD
DSA
catheter based digital subtraction angiography
What is the most frequently used technique in diagnosing FMD
CTA
MRA
Duplex ultrasonography
String of beads appearance
Regarding the location of disease with in the arteries, what differentiates atherosclerosis from FMD
Atherosclerosis primarily effects the ostium or proximal segment
FMD primarily effects the middle or distal arterial segment
What artery is primarily effected with FMD?
70% of the time the renal artery
What is one of the most common causes of resistant hypertension?
Primary aldosteronism. However most patients are normokalemic at presentation.
