passmed Flashcards
A patient has a cardiac output of 6 L/min and a heart rate of 60/min. Her end-diastolic left ventricular volume is 200ml.
What is her left ventricular ejection fraction (LVEF)?
50%
First, calculate the stroke volume:
Cardiac output = heart rate x stroke volume.
Stroke volume = cardiac output / heart rate.
= 6000/60 = 100ml.
Then calculate LVEF:
LVEF = (stroke volume / end diastolic LV volume) x 100.
= (100/200) x 100.
= 50%.
EF equally stroke volume divided LDV
ejection faction equals what
stroke volume divided by LDV
different types of heart failure
Heart failure with preserved ejection fraction (HFpEF) is correct. It is usually caused by ventricular stiffness secondary to long-standing hypertension or ventricular hypertrophy. This would lead to abnormal filling of the ventricles during diastole and a normal ejection fraction on the echocardiogram (>50%).
Heart failure with reduced ejection fraction (HFrEF) is incorrect as this patient has an ejection fraction of 60%, and a normal ejection fraction is >50%.
High output heart failure is incorrect. High output heart failure is usually caused by obesity, hepatic disease and lung disease. It may present concurrently with HFpEF. However, in the absence of such risk factors, this is not the most appropriate answer.
Left ventricular failure is incorrect. This patient presents with signs of pulmonary and peripheral oedema which suggests that both left and right ventricles are affected. This should be termed as ‘congestive cardiac failure’ rather than left ventricular failure.
Right ventricular failure is incorrect. This patient presents with signs of pulmonary and peripheral oedema which suggests that both left and right ventricles are affected. This should be termed as ‘congestive cardiac failure’ rather than right ventricular failure.
what is high output heart failure
High-output heart failure refers to a situation where a ‘normal’ heart is unable to pump enough blood to meet the metabolic needs of the body.
Causes anaemia arteriovenous malformation Paget's disease Pregnancy thyrotoxicosis thiamine deficiency (wet Beri-Beri)
how does amiodarone affect warfarin
decreases its metabolism
what are the two main reasons fro using digoxin
Digoxin can be either used in heart failure with reduced ejection fraction, as it inhibits Na+/K+ ATPase and improves contractility, or as a secondary option in atrial fibrillation because it can also inhibit the AV node.
does hypertension normally cause symptoms
no
‘egg-on-side’.
Transposition of the great arteries has an ‘egg-on-side’ appearance on x-rays
transposition of great arteries due to failure of what
e failure of the aorticopulmonary septum to spiral during septation.
Global ST and PR segment changes:
pericarditis
greatest proportion of musculi pectinati found
right atrium
for stress and dilation
facial artery branch of
external carotid
nkle brachial pressure index (ABPI)
1 Normal
0.6-0.9 Claudication
0.3-0.6 Rest pain
<0.3 Impending
what is intermittent claudication
intermittent claudication: aching or burning in the leg muscles following walking
patients can typically walk for a predictable distance before the symptoms start
usually relieved within minutes of stopping
not present at rest
management of critical limb ischaemia
Risk factor modification e.g. smoking cessation, treat hypertension and high cholesterol, prescribe clopidogrel
Supervised exercise programs to increase blood flow
Percutaneous transluminal angioplasty
Surgical reconstruction i.e. bypass graft using the saphenous vein
Amputation
myocardial necrosis marker
troponin I
is the posterior cerebral artery closely related to the 3rd cranial nerve
yes
if you are treating angina with beta blockers but person has asthma do you need to replace them
yes
An unusually tall 43-year-old lady presents to the surgical clinic with bilateral inguinal hernias. She develops chest pain and collapses. As part of her investigations a chest x-ray shows evidence of mediastinal widening. What is the most likely underlying diagnosis?
aortic dissection
Marfans syndrome may present with a variety of connective tissue disorders such as bilateral inguinal hernia. They are at high risk of aortic dissection, as in this case.
A 21-year-old woman was admitted earlier in the day with a fractured tibia following a footballing injury. She was managed with surgical repair but has suddenly developed a tachycardia on the recovery ward. Her observations show a heart rate of 169 beats/minute, respiratory rate of 18 breaths/minute, and blood pressure of 75/52 mmHg. Her ECG shows ventricular tachycardia. The doctor opts for synchronised DC cardioversion.
Which of the following would be the most appropriate management?
DC cardioversion shock synchronised to the ECG R wave
An electrocardiogram (ECG) was done and showed rapid, irregular QRS complexes, which appear to be ‘twisting’ around the baseline.
tosardes de pointes
A 72-year-old man attends the emergency department following a syncopal episode. He has an ECG which shows a prolonged PR interval, with every second QRS complex dropped. The width of the QRS complexes are normal.
In which part of the heart is the conduction delay likely to be coming from?
AVN
The PR interval represents the time between atrial depolarisation and ventricular depolarisation
2nd degree heart block
pale ulcer which has a ‘punched out’ appearance
arterial ulcer - painful at night and sitting in chair
During surgery on his neck, a man suffers a vagus nerve injury where the nerve is cut near the exit from the skull. He wakes up with a high heart rate and high blood pressure due to loss of parasympathetic tone.
Which of the following other features would be expected with a vagus nerve injury?
Hoarse voice
A fourth-year medical student is asked to examine the abdomen of a 59-year-old man who presented to hospital with generalised abdominal pain. He has a past medical history of chronic obstructive pulmonary disease. The student reported generalised abdominal tenderness but with no peritonism, masses or organomegaly. The student described the liver as ‘bouncing up and down periodically’ on the tips of her fingers.
What is the likely cause for this?
Tricuspid regurgitation presents with pulsatile hepatomegaly due to backflow of blood into the liver during the cardiac cycle
The student is describing pulsatile hepatomegaly, where the liver pulsates with the cardiac cycle. This results from retrograde flow of blood from the heart to the peripheral circulation due to an incompetent valve - hence tricuspid regurgitation.
Hepatitis, mitral stenosis or mitral regurgitation do not cause pulsatile hepatomegaly.
what should all patients with angina be given ob hospital admission
Medication
all patients should receive aspirin and a statin in the absence of any contraindication
sublingual glyceryl trinitrate to abort angina attacks
what does warfarin do to PT and INR
increases both
In mitral stenosis, left atrial pressure is increased which equates to increased pulmonary capillary wedge pressure (PCWP)
true
what is orthopnea
Orthopnea means you find it harder to breathe when you lie down because of fluid in your lungs
what can differentiate heart failure from COPD
Orthopnoea can differentiate heart failure from COPD
patients with recurrent DVT and PE what should you offer r
inferior vena cava (IVC) filters
first line for PE
Thrombolysis
thrombolysis is now recommended as the first-line treatment for massive PE where there is circulatory failure (e.g. hypotension)
The bladder’s detrusor tone is maintained by both the sympathetic and parasympathetic nervous system. The sympathetic nervous system is responsible for relaxing the detrusor, while the parasympathetic nervous system mediates the contraction of the muscle, via M3 muscarinic receptors. As such, antimuscarinics, such as oxybutynin, are typically prescribed to patients with urinary incontinence.
Mirabegron is also used to treat urinary incontinence. However, it is a β3 adrenergic receptor agonist.
Meropenem
antibiotic that is used for organisms that are resistant to most beta-lactams. However, it is usually used as last-line therapy due to its adverse effects.
what is Alfuzosin
alpha blocker treatment for BPH
what is valsalva manoeuvre
The Valsalva maneuver is a breathing method that may slow your heart when it’s beating too fast. To do it, you breathe out strongly through your mouth while holding your nose tightly closed. This creates a forceful strain that can trigger your heart to react and go back into normal rhythm
aortic stenosis
In some individuals a persistent left sided SVC drains into the right atrium via an enlarged orifice of the
coronary sinus
cor pulmonate what is it
abnormal enlargement of the right side of the heart as a result of disease of the lungs or the pulmonary blood vessels.
Pistol shot femoral pulses
aortic regurgitation
Malar flush
mitral stenosis
Quincke’s sign refers to nail bed pulsation
aortic regurgitation
Hepatomegaly
aortic stenosis
This is suggested by the ejection systolic murmur, the slow-rising pulse, and the history of progressive heart failure symptoms. S4 (fourth heart sound) occurs when the left atrium contracts with greater force to overcome resistance from a less compliant ventricle.
aortic stenosis
Dressler syndrome is an autoimmune-mediated pericarditis occurring 2-6 weeks after a myocardial infarction
true
do thiazides cause gout
yes
eggs on strings
Transposition of great vessels is due to the failure of the aorticopulmonary septum to spiral
The T wave in an ECG corresponds to repolarisation, which is also phase 3 of the cardiac action potential.
Repolarisation due to efflux of potassium
do NSAIDs reduce anti-hypertensive effect of ACEi
This patient has osteoarthritis and is most likely to be taking NSAIDs. NSAID’s reduce the anti-hypertensive effects of ACE-inhibitors. They can also compound the hyperkalaemic effects of ACE-inhibitors. This is why his blood pressure is not adequately controlled.
do loop diuretic cause low or high potassium
low
A 42-year-old woman presents with a 6-month history of progressive dyspnoea on exertion and fatigue. She has no significant past medical history and takes no regular medications.
On examination, the lungs are clear to auscultation; a loud P2 heart sound is noted. A chest X-ray demonstrates enlarged pulmonary artery shadows.
What is implicated in causing the disease process?
endothelin
Endothelin causes pulmonary vasoconstriction (hence why antagonists are used in primary pulmonary hypertension)
site where the vertebral arteries fuse together to form the basilar artery
base of pons
The……. ………. is the embryological structure that gives rise to the ascending aorta and the pulmonary trunk
trunks arteriousus - aortic dissection
ng QT syndrome most commonly leads to
tosardes de pointes
ng QT syndrome most commonly leads to
tosardes de pointes
Long QT syndrome (LQTS) is an inherited condition associated with delayed repolarization of the ventricles. It is important to recognise as it may lead to ventricular tachycardia/torsade de pointes and can therefore cause collapse/sudden death. The most common variants of LQTS (LQT1 & LQT2) are caused by defects in the alpha subunit of the slow delayed rectifier potassium channel. A normal corrected QT interval is less than 430 ms in males and 450 ms in females.
normal pr interval
under 0.2sec
A 63-year-old woman was successfully cardioverted for an unstable broad complex tachycardia. The cardiologist decides to commence oral amiodarone at 200mg three times a day, and wean at weekly intervals until a maintenance dose of 200mg once daily.
What is the reason for this dosing strategy?
has a long Half life
Amiodarone has a very long half-life of 20-100 days - loading doses are therefore often needed
embryological development of coronary sinus
The sinus venosus has both left and right horns:
The coronary sinus is a derivative of the left horn.
The smooth part of the right atrium is a derivative of the right horn
why does the DA normally close
The ductus arteriosus closes with the first breaths due to increased pulmonary flow which enhances prostaglandins clearance
A 52-year-old male presents with central chest pain. On examination, he has an mitral regurgitation murmur. An ECG shows ST elevation in leads V1 to V6. There is no ST elevation in leads II, III and aVF. What is the diagnosis?
anterior MI
furosemide acts on what limb of the loop of henle
ascending thick limb
Baroreceptors are stimulated by arterial stretch
ECG features of hypokalaemia
ECG features of hypokalaemia U waves small or absent T waves (occasionally inversion) prolong PR interval ST depression long QT
J waves are seen in hypothermia
vascular cell adhesion molecule-1 (VCAM-1) is a protein expressed on the endothelial cells of the internal surface of blood vessels in response to pro-atherosclerotic conditions. It is not expressed under baseline conditions. VCAM-1 binds to a molecule on lymphocytes, monocytes and eosinophils to cause adhesion of these cells to the endothelium. The expression of VCAM-1 is upregulated in response to various cytokines. Studies have shown that VCAM-1 is critical in the development of atherosclerosis.
\
Endothelium changes include pro-inflammatory, pro-oxidant, proliferative and reduced nitric oxide bioavailability
troponins
Subunits of troponin
troponin C: binds to calcium ions
troponin T: binds to tropomyosin, forming a troponin-tropomyosin complex
troponin I: binds to actin to hold the troponin-tropomyosin complex in place
A 56-year-old male is seen by his cardiologist in clinic some months after having had a coronary artery bypass procedure. Which vessel is most commonly used in this procedure?
intermal mammary artery
saphnosu
therosclerosis is a complex process which develops over a number of years. A number of changes can be seen:
initial endothelial dysfunction is triggered by a number of factors such as smoking, hypertension and hyperglycaemia
this results in a number of changes to the endothelium including pro-inflammatory, pro-oxidant, proliferative and reduced nitric oxide bioavailability
fatty infiltration of the subendothelial space by low-density lipoprotein (LDL) particles
monocytes migrate from the blood and differentiate into macrophages. These macrophages then phagocytose oxidized LDL, slowly turning into large ‘foam cells’. As these macrophages die the result can further propagate the inflammatory process.
smooth muscle proliferation and migration from the tunica media into the intima results in formation of a fibrous capsule covering the fatty plaque.
Taking the coronary arteries as an example, once a plaque has formed a number of complications can develop:
the plaque forms a physical blockage in the lumen of the coronary artery. This may cause reduced blood flow and hence oxygen to the myocardium, particularly at times of increased demand, resulting clinically in angina
the plaque may rupture, potentially causing a complete occlusion of the coronary artery. This may result in a myocardial infarction
most common cause of heart failure
In the western world, the most common cause of heart failure is ischaemic heart disease. This is then followed by high blood pressure, various cardiomyopathies, arrhythmias and heart valve problems.
COPD can be associated with cor pulmonale (just right heart failure) however, this is still less common than ischaemic heart disease as a cause.
contents from medial to lateral of popliteal fossa
The contents of the popliteal fossa are (from medial to lateral): Popliteal artery Popliteal vein Tibial nerve Common peroneal nerve
The common iliac veins fuse with the IVC at
L5
highest resistance vessel and contributes most to blood pressure
The arterioles are the site of highest resistance in the cardiovascular system. They therefore contribute most to the total peripheral resistance
patient is diagnosed with first-degree heart block which is shown on his ECG by an elongated PR interval. The PR interval relates to a particular period in the electrical conductance of the heart.
Which of the following could cause the PR interval to decrease?
Sympathetic activation increases heart rate by increasing conduction velocity of the AV node
The PR interval represents the time between atrial depolarisation and ventricular depolarisation
what problem affects this
WPW
rheumatic fever management
Outline of management
antibiotics: oral penicillin V
anti-inflammatories: NSAIDs are first-line
treatment of any complications that develop e.g. heart failure
Rheumatic fever develops through molecular mimicry of the bacterial M protein
pathology of rheumatic fever
preload stretch and afterlaod pressure
treadmill test
Increased venous return from the muscles, increases preload and increases stroke volume
Increased stroke volume increases pulse pressure
Aortic stenosis would decrease stroke volume as end systolic volume would increase. This is because of an increase in afterload, an increase in resistance that the heart must pump against due to a hard stenotic valve.
Heart failure is characterized by reduced ejection fraction and therefore stroke volume.
Decreased blood volume would decrease preload due to reduced venous return.
Impaired ventricular relaxation would reduce diastolic filling and therefore preload.
work it out harry
what between layers of artery
Often, the internal elastic lamina separates the tunica intima from the tunica media. The tunica media is composed chiefly of circumferentially arranged smooth muscle cells. Again, the external elastic lamina often separates the tunica media from the tunica adventitia.
The wall of a blood vessel is divided into a tunica intima, tunica media and tunica adventitia. The tunica intima forms the innermost layer and this contains endothelial cells separated by gap junctions. The middle layer is the tunica media, this contains the smooth muscle cells and is separated from the intima by the internal elastic lamina and the adventitia by the external elastic lamina. The outermost layer is the tunica adventitia and this contains the vasa vasorum, fibroblast and collagen.
One question is what segment of the ECG represents ventricular repolarization?
t wave
decreases preload and after load
BNP
plataeu phase
Plateau in the myocardial action potential is caused by slow influx of calcium
apple green birefringence with polarised light
amyloidosis
does ventricular rate change with ventilation
yes
Sinus arrhythmia is a normal physiological phenomenon which is commonly seen in young, healthy patients. The heart rate varies with ventilation, inspiration increases heart rate and expiration decreases (only very slightly but detectable on ECG). This is because of vagal tone which is decreased in the inspiratory phase and vice versa. The P-R interval remains constant as there is no heart block, and the varying P-P intervals illustrate changes in the ventricular heart rate.
Patients with heart failure with reduced LVEF should be given
beta blocker and ACEi
what nerve lies between the superior cerebellar and posterior cerebral arteries
The oculomotor nerve
Where is the site of action of bendroflumethiazide?
Proximal part of the distal convoluted tubules
Thiazides/thiazide-like drugs (e.g. indapamide) - inhibits sodium reabsorption by blocking the Na+-Cl− symporter at the beginning of the distal convoluted tubule
what drug cause low sodium used in blood pressure
also causes gout
thiazides
hebesian veins contribute to the venous drainage of the heart drain into
atrium
chest pain to pericarditis relieved when
Chest pain due to pericarditis is often relieved by sitting/leaning forward
A 23-year-old man has a routine ECG performed. Which part of the tracing obtained represents atrial repolarisation?
The process of atrial repolarisation is generally not visible on the ECG strip. It occurs during the QRS complex.
Which vessel connects the aorta and pulmonary artery in foetal life?
DA
what is amyloidosis
Amyloidosis (am-uh-loi-DO-sis) is a rare disease that occurs when an abnormal protein, called amyloid, builds up in your organs and interferes with their normal function
The build-up of amyloid proteins (deposits) can make it difficult for the organs and tissues
types of amylodisosi
AL amyloidosis in patients with symptomatic multiple myeloma or other B-cell - most common
This page focuses on AL amyloidosis, which is the most common type, and on ATTR amyloidosis, which often runs in families.
Systemic AA amyloidosis is a long-term complication of several chronic inflammatory disorders - e.g. rheumatoid arthritis, ankylosing spondylitis, Crohn’s disease, malignancies and conditions predisposing to recurrent infections.
St segment
Represents period which the entire ventricle is depolarized and roughly corresponds to the plateau phase of the ventricular action potential
atherosclerosis causes Postural hypotension - due to reduced stretch so barorecpros can detect
true
