Cardiology Flashcards
Pulsus parodoxus
Greater than the normal (10 mmHg) fall in systolic blood pressure during inspiration → faint or
absent pulse in inspiration
* Severe asthma, cardiac tamponade
Slow-rising/plateau
- Aortic stenosis
Collapsing
Aortic regurgitation
* Patent ductus arteriosus
* Hyperkinetic (anemia, thyrotoxic, fever, exercise/pregnancy)
Pulsus alternans
Regular alternation of the force of the arterial pulse
* Severe LVF
Bisferiens pulse
‘Double pulse’ - two systolic peaks
* Mixed aortic valve disease
Jerky’ pulse
Hypertrophic obstructive cardiomyopathy*
S1 heart sound
Closure of mitral and tricuspid valves
* Soft if long PR or mitral regurgitation
* Loud in mitral stenosis
* Variable intensity in complete heart block
Causes of a loud S2
Hypertension: systemic (loud A2) or pulmonary (loud P2)
* Hyperdynamic states
* Atrial septal defect without pulmonary hypertension
Causes of a soft S2
Aortic stenosis
Causes of fixed split S2
Atrial septal defect
Causes of a widely split S2
Deep inspiration
* RBBB
* Pulmonary stenosis
* Severe mitral regurgitation
Causes of a reversed (paradoxical) split S2 (P2 occurs before A2)
LBBB
* Severe aortic stenosis
* Right ventricular pacing
* WPW type B (causes early P2)
* Patent ductus arteriosus
S3 heart sound
Caused by diastolic filling of the ventricle
* Considered normal if < 30 years old (may persist in women up to 50 years old)
* Heard in left ventricular failure, constrictive pericarditis
* Gallop rhythm (S3) is an early sign of LVF
s4 sound
may be heard in aortic stenosis, HOCM, hypertension
* caused by atrial contraction against a stiff ventricle
* in HOCM a double apical impulse may be felt as a result of a palpable S4
Kussmaul’s sign
paradoxical rise in JVP during inspiration seen in constrictive pericarditis. Kussmaul’s sign → constrictive pericarditis
JVP ‘a’ wave
a’ wave = atrial contraction
* Large if atrial pressure e.g. Tricuspid stenosis, pulmonary stenosis, pulmonary
hypertension
* Absent if in atrial fibrillation
Cannon ‘a’ waves
caused by atrial contractions against a closed tricuspid valve
* Are seen in complete heart block, ventricular tachycardia/ectopics, nodal rhythm,
single chamber ventricular pacing
Regular cannon waves
- Ventricular tachycardia (with 1:1 ventricular-atrial conduction)
- Atrio-ventricular nodal re-entry tachycardia (AVNRT)
Irregular cannon waves
Complete heart block
c wave JVP
‘c’ wave
* Closure of tricuspid valve
* Not normally visible
‘v’ wave JVP
Giant v waves in tricuspid regurgitation
‘x’ descen
Fall in atrial pressure during ventricular systole
y’ descent
Opening of tricuspid valve
Left ventricular ejection fraction
stroke volume / end diastolic LV volume) * 100%
Stroke volume
end diastolic LV volume - end systolic LV volume
ECG normal variants:
- Junctional rhythm
- First degree heart block
- Wenckebach phenomenon
LBBB is always pathological
ECG changes may be seen in hypothermia:
Bradycardia
* ‘J’ wave - small hump at the end of the QRS complex
* First degree heart block
* Long QT interval
* Atrial and ventricular arrhythmias
Digoxin ECG features:
Down-sloping ST depression (‘reverse tick’)
* Flattened/inverted T waves
* Short QT interval
* Arrhythmias e.g. AV block, bradycardia
Causes of ST depression:
Normal if upward sloping
* Ischemia
* Digoxin
* Hypokalemia
* Syndrome X
LBBB
Diagnosis: criteria to diagnose a left bundle branch block on ECG:
* Rhythm must be supraventricular in origin (P wave present)
* QRS duration ≥ 120 ms (3 small squares)
* QS or rS complex in lead V1(note: r is small-not capital = small-not tall r in ECG)
* RsR wave in lead V6.
Prolonged PR interval causes
Causes:
* Idiopathic
* Ischemic heart disease
* Digoxin toxicity
* Hypokalemia*
* Rheumatic fever
* Aortic root pathology e.g. Abscess secondary to endocarditis
* Lyme disease
* Sarcoidosis
* Myotonic dystrophy
causes of left axis deviation
- Left anterior hemiblock
- Left bundle branch block
- Wolff-parkinson-white syndrome* - right-
sided accessory pathway - Hyperkalemia
- Congenital: ostium PRIMUM ASD,
tricuspid atresia - Minor LAD in obese people
Causes of right axis deviation (RAD)
Right ventricular hypertrophy
* Left posterior hemiblock
* Chronic lung disease
* Pulmonary embolism
* Ostium SECUNDUM ASD
* Wolff-parkinson-white syndrome* - left-
sided accessory pathway
* Normal in infant < 1 years old
* Minor RAD in tall people
Isolated systolic hypertension (ISH)
common in the elderly, affecting around 10% of people older than 70 years old. The Systolic Hypertension in the Elderly Program (SHEP) back in 1991 established that treating ISH ↓ both strokes and ischemic heart disease. Drugs such as thiazides were recommended as first line agents. This approach is not contraindicated by the 2006 NICE guidelines which recommend treating ISH in the same stepwise fashion as standard hypertension
Hypertension: initial treatment
Patients < 55-years-old: ACE inhibitor
* Patients > 55-years-old or of Afro-Caribbean origin: calcium channel blocker or thiazide
diuretic
The target blood pressure
140/90 mmHg
Causes of secondary HTN
Renal - accounts for 80% of secondary hypertension o Glomerulonephritis
o Pyelonephritis
o Adultpolycystickidneydisease o Renal artery stenosis
Endocrine disorders
o Cushing’s syndrome
* Others
New drugs
o Primary hyperaldosteronism including Conn’s syndrome
o Liddle’s syndrome
o Congenital adrenal hyperplasia (11-β hydroxylase deficiency) o Pheochromocytoma
o Acromegaly
Direct renin inhibitors
Aliskiren (branded as Rasilez)
* By inhibiting renin blocks the conversion of angiotensinogen to angiotensin I
* No trials have looked at mortality data yet. Trials have only investigated fall in blood pressure.
Initial trials suggest aliskiren ↓ blood pressure to a similar extent as angiotensin converting
enzyme (ACE) inhibitors or angiotensin-II receptor antagonists
* Adverse effects were uncommon in trials although diarrhea was occasionally seen
* Only current role would seem to be in patients who are intolerant of more established
antihypertensive drugs
Examples of centrally acting antihypertensives include:
Methyldopa: used in the management of hypertension during pregnancy
* Moxonidine: used in the management of essential hypertension when conventional
antihypertensives have failed to control blood pressure
* Clonidine: the antihypertensive effect is mediated through stimulating α-2 adrenoceptors in the
vasomotor center.
The blood pressure target
140/90 mmHg (normal and diabetes)
If there is end-organ damage the target
is 130/80 mmHg
HTN and diabetes
ACE inhibitors are first-line*. Otherwise managed according to standard NICE hypertension
guidelines
* BNF advises to avoid the routine use of beta-blockers in uncomplicated hypertension,
Pericarditis Features
Features
* Chest pain: may be pleuritic. Is often relieved by sitting forwards
* Other symptoms include non-productive cough, dyspnea and flu-like symptoms
* Pericardial rub
* Tachypnea
* Tachycardia
Pericarditis causes
Causes
* Viral infections (Coxsackie)
* TB
* Uremia (causes ‘fibrinous’ pericarditis)
* Trauma
* Post MI, Dressler’s syndrome
* Connective tissue disease
* Hypothyroidism
Pericarditis ECG changes
Widespread ‘saddle-shaped’ ST elevation
* PR depression (most sensitive)
Myocarditis: causes
- Viral: coxsackie, HIV
- Bacteria: diphtheria, clostridia
- Spirochetes: Lyme disease
- Protozoa: Chagas’ disease, toxoplasmosis
- Autoimmune
- Drugs
strongest risk factor for developing infective endocarditis
is a previous episode of endocarditis.
Other factors include:
* Previously normal valves (50%, typically acute presentation)
* Rheumatic valve disease (30%)
* Prosthetic valves
* Congenital heart defects
* Intravenous drug users (IVDUS, e.g. Typically causing tricuspid lesion)
Most common cause of endocarditis
Streptococcus viridans
* Staphylococcus epidermidis if < 2 months post valve surger
streptococcus viridans - endocarditis
most common cause - 40-50%) → has good prognosis
Staphylococcus epidermidis - endocarditis
ass/w prosthetic valves
Staphylococcus aureus - endocarditis
especially acute presentation, IVDUS)
Streptococcus bovis endocarditis
associated with colorectal cancer
Bacteroides fragilis endocardtis
endocarditis is very rare complication of colonic resection, bacteria reaches
heart via venous return, this is why it affects right > left side → Treat with Metronidazole
Culture negative causes (BP-CHB) endocarditis
Brucella
* Prior antibiotic therapy
* Coxiella burnetii
* HACEK: Hemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
* Bartonella
Poor prognostic factors endocarditis
- Staph aureus infection
- Prosthetic valve (especially ‘early’, acquired during surgery)
- Culture negative endocarditis
- Low complement levels
Diagnosis endocarditis
Pathological criteria positive, or
* 2 major criteria, or
* 1 major and 3 minor criteria, or
* 5 minor criteria
Major criteria endocarditis
- Positive blood cultures
* Two positive blood cultures showing typical organisms consistent with infective endocarditis,
such as Streptococcus viridans and the HACEK group.
* Persistent bacteremia from two blood cultures taken > 12 hours apart or three or more positive
blood cultures where the pathogen is less specific such as Staph aureus and Staph epidermidis.
* Positive serology for Coxiella burnetii, Bartonella species or Chlamydia psittaci.
* Positive molecular assays for specific gene targets - Evidence of endocardial involvement
* Positive echocardiogram (oscillating structures, abscess formation, new valvular regurgitation
or dehiscence of prosthetic valves), or
* New valvular regurgitation
Minor criteria endocarditis
Predisposing heart disease
* Microbiological evidence does not meet major criteria
* Fever > 38oc
* Vascular phenomena: major emboli, splenomegaly, clubbing, splinter hemorrhages, petechiae
or purpura
* Immunological phenomena: glomerulonephritis, Osler’s nodes, Roth spots (boat shaped
hemorrhages in retina)
* Elevated CRP or ESR
Current management guidelines endocarditis
Initial blind therapy - flucloxacillin + gentamicin (benzylpenicillin + gentamicin if symptoms
less severe)
* Initial blind therapy if prosthetic valve is present or patient is penicillin allergic - vancomycin
+ rifampicin + gentamicin
* Endocarditis caused by staphylococci - flucloxacillin (vancomycin + rifampicin if penicillin
allergic or MRSA)
* Endocarditis caused by streptococci → benzylpenicillin + gentamicin (vancomycin +
gentamicin if penicillin allergic)
Initial blind therapy - endocardtisis
Initial blind therapy - flucloxacillin + gentamicin (benzylpenicillin + gentamicin if symptoms
less severe)
Initial blind therapy if prosthetic valve is present or patient is penicillin allergic - vancomycin
+ rifampicin + gentamicin
endocarditis treatment when caused by staphylococc
- flucloxacillin (vancomycin + rifampicin if penicillin
allergic or MRSA)
endocarditis treatment when caused by streptococci
benzylpenicillin + gentamicin (vancomycin +
gentamicin if penicillin allergic)
Heart Failure: treatments
ACE inhibitors (SAVE, SOLVD, CONSENSUS)
* Spironolactone (RALES) (improved prognosis not mortality)
* β-blockers (CIBIS)
* Hydralazine with nitrates (VHEFT-1)
Digoxin in HF
Digoxin has also not been proven to ↓ mortality in patients with heart failure. It may however improve symptoms due to its inotropic properties. Digoxin is strongly indicated if there is coexistent atrial fibrillation
Left ventricular ejection fraction =
(stroke volume / end diastolic LV volume ) * 100%
Stroke volume =
end diastolic LV volume - end systolic LV volume
Cardiac output =
stroke volume x heart rate
Pulse pressure =
Systolic Pressure - Diastolic Pressure
Systemic vascular resistance =
mean arterial pressure / cardiac output
Donepezil adverse effects
is relatively contraindicated in patients with bradycardia
adverse effects include insomnia
Diastolic Heart Failure:
Basics:
* 1/3 of heart failure is diastolic (normal Left Ventricular Systolic Function-LVSF)
* Mortality in Diastolic HF is 5-8% (lower than Systolic HF: 10-15%)
Diastolic Heart Failure: Management:
Initially, reduction of pulmonary venous pressure (PVP) and congestion, using diuretics
* ARBs are superior to ACE inhibitors
Cardiac Tamponade: Features
- Raised JVP, with an absent Y descent - this is due to the limited right ventricular filling
- Tachycardia
- Hypotension
- Muffled heart sounds
- Pulsus paradoxus (which occurs also in Asthma)
- Kussmaul’s sign (much debate about this) (more in constrictive pericarditis)
- ECG: electrical alternans
key differences between constrictive pericarditis and cardiac tamponade are:
Cardiac tamponade
Absent Y descent
Pulsus paradoxu
Kussmaul’s sign
pericarditis
X + Y present
AbsentPericardial calcification on CXR
MUGA
Multi Gated Acquisition Scan, also known as radionuclide angiography
* Radionuclide (technetium-99m) is injected intravenously
* The patient is placed under a gamma camera
* May be performed as a stress test
* Can accurately measure left ventricular ejection fraction. Typically used before and after cardiotoxic drugs are used
Cardiac Computed Tomography (CT)
useful for assessing suspected IHD, using two main methods:
* Calcium score: there is known to be a correlation between the amount of atherosclerotic plaque calcium and the risk of future ischemic events. Cardiac CT can quantify the amount of calcium
producing a ‘calcium score’
* Contrast enhanced CT: allows visualization of the coronary artery lumen
Cardiac MRI:
gold standard for providing structural images of the heart. It is particularly useful when assessing congenital heart disease, determining right and left ventricular mass and differentiating forms of cardiomyopathy. Myocardial perfusion can also be assessed following the administration of gadolinium. Currently CMR provides limited data on the extent of coronary artery disease.
Exercise ECG:
USELESS in patients with:
* Conduction abnormalities
* resting (ECG) abnormalities like ST segment depression of >1mm
* WPW
* Digoxin
* Ventricular paced rhythm
mmediate management of suspected acute coronary syndrome (ACS)
Glyceryl trinitrate
* Aspirin 300mg. NICE do not recommend giving other antiplatelet agents (i.e. Clopidogrel)
outside of hospital
* Do not routinely give oxygen, only give if sats < 94%*
* Perform an ECG as soon as possible but do not delay transfer to hospital. A normal ECG does
not exclude ACS
refer chest pain
Current chest pain or chest pain in the last 12 hours with an abnormal ECG: emergency admission
* Chest pain 12-72 hours ago: refer to hospital the same-day for assessment
* Chest pain > 72 hours ago: perform full assessment with ECG and troponin measurement
before deciding upon further action
in chest pain NICE suggest the following in terms of oxygen therapy:
Do not routinely administer oxygen, but monitor oxygen saturation using pulse oximetry as soon as possible, ideally before hospital admission. Only offer supplemental oxygen to:
* People with oxygen saturation (SpO2) < 94% who are not at risk of hypercapnic respiratory failure, aiming for SpO2 of 94-98%
* People with chronic obstructive pulmonary disease who are at risk of hypercapnic respiratory failure, to achieve a target SpO2 of 88-92% until blood gas analysis is available.
NICE define anginal pain as the following:
Constricting discomfort in the front of the chest, neck, shoulders, jaw or arms o Precipitated by physical exertion
o Relieved by rest or GTN in about 5 minutes
* Patients with all 3 features have typical angina
* Patients with 2 of the above features have atypical angina
* Patients with 1 or none of the above features have non-anginal chest pain
Stable Angina: management
In good exercise tolerance, consider medical therapy before angiography (β-
blocker is the most important)
* If pain is worsening, no need for exercise test, directly do angiography (Cath)
Medication stable angina
All patients should receive aspirin and a statin in the absence of any contraindication
* Sublingual glyceryl trinitrate to abort angina attacks
* β-blocker is the preferred initial treatment. For patients unable to take a β-blocker there is no
clear guidelines on the best alternative. Options include a rate-limiting calcium-channel blocker (verapamil or diltiazem); a long-acting dihydropyridine calcium-channel blocker (e.g. modified- release nifedipine); a nitrate; or a potassium-channel activator
If there is a poor response to initial treatment then the β-blocker should be ↑ to the maximum tolerated dose (e.g. atenolol 100mg od)
* Again, there are no clear guidelines on the next step treatment. CKS advise adding a long-acting dihydropyridine (e.g. nifedipine, amlodepine, felodipine) although other options include isosorbide mononitrate and nicoran
Prinzmetal angina
dihydropyridine calcium channel blocker (depine family; amlodepine)
Nitrate tolerance stable
Many patients who take nitrates develop tolerance and experience ↓ efficacy
* BNF advises that patients who develop tolerance should take the second dose of isosorbide mononitrate after 8 hours, rather than after 12 hours. This allows blood-nitrate levels to fall for
4 hours and maintains effectiveness
* This effect is not seen in patients who take modified release isosorbide mononitra
Ivabradine (Procoralan)
A new class of anti-anginal drug which works by reducing the heart rate
* Acts on the If (‘funny’) ion current which is highly expressed in the sinoatrial node, reducing
cardiac pacemaker activity
* Adverse effects: visual effects, particular luminous phenomena, are common. Bradycardia, due
to the mechanism of action, may also be seen
* There is no evidence currently of superiority over existing treatments of stable angina
NICE 2011 Guidelines:
* In good exercise tolerance, consider medical therapy before angiography (β-
blocker is the most important)
* If pain is worsening, no need for exercise test, directly do angiography (Cath)
Acute Coronary Syndrome: all its should get
All patients should receive
- Aspirin 300mg
- Nitrates or morphine to relieve chest pain if required
Clopidogrel 300mg and low molecular weight heparin (principally enoxaparin) should also be added to higher risk patients
lopidogrel 300mg should be given to patients with a predicted 6 month mortality of more than 1.5% or patients who may undergo percutaneous coronary intervention within 24 hours of admission to hospital. Clopidogrel should be continued for 12 months.
Acute Coronary Syndrome: Antithrombin treatment.
Fondaparinux should be offered to patients who are not at a high risk of bleeding and who are not having angiography within the next 24 hours. If angiography is likely within 24 hours or a patient’s creatinine is > 265 μmol/l unfractionated heparin should be given.
Clopidogrel (Plavix®) Interactions
Concurrent use of proton pump inhibitors (PPIs) may make clopidogrel less effective (MHRA July 2009)
* This advice was updated by the MHRA in April 2010, evidence seems inconsistent but omeprazole and esomeprazole still cause for concern. Other PPIs such as lansoprazole should be OK
Intravenous glycoprotein IIb/IIIa receptor antagonists ACS
(eptifibatide or tirofiban) should be given to patients who have an intermediate or higher risk of adverse cardiovascular events (predicted 6-month mortality above 3.0%), and who are scheduled to undergo angiography within 96 hours of hospital admission.
Coronary angiography
should be considered within 96 hours of first admission to hospital to patients who have a predicted 6-month mortality above 3.0%. It should also be performed as soon as possible in patients who are clinically unstable.
Aspirin moa
Antiplatelet - inhibits the production of thromboxane A2
Clopidogrel moa
Antiplatelet - inhibits ADP binding to its platelet receptor
Enoxaparin moa
Activates antithrombin III, which in turn potentiates the inhibition of coagulation factors Xa
Fondaparinux
Activates antithrombin III, which in turn potentiates the inhibition of coagulation factors Xa
Bivalirudin
Reversible direct thrombin inhibitor
Poor prognostic factors: ACS
Age
* Development (or history) of heart failure,
Killip class*
* Peripheral vascular disease
* ↓ systolic blood pressure
* Initial serum creatinine concentration
* Elevated initial cardiac markers
* Cardiac arrest on admission
* ST segment deviation
Anteroseptal MI
V1-V4
Left anterior descending
Inferior MI
II, III, aVF
Right coronary
Anterolateral MI
V4-6, I, aVL
Left anterior descending or left circumflex
Lateral MI
I, aVL +/- V5-6
Left circumflex
Posterior MI
Tall R waves V1-2 Usually left circumflex, also right coronary
Posterior aortic or coronary sinus ->
left coronary artery (LCA)
Anterior aortic or coronary sinus _>
right coronary artery (RCA)
- LCA (Left Main, LM) →
LAD + circumflex
RCA →
posterior descending
RCA supplies
SA node in 60%, AV node in 90%
MI ll patients should be offered the following drugs
- ACE inhibitor
- β-blocker
- Aspirin
- Statin
Clopidogrel post MI
After an ST-segment-elevation MI, patients treated with a combination of aspirin and clopidogrel during the first 24 hours after the MI should continue this treatment for at least 4 wk
* (NSTEMI): following the 2010 NICE unstable angina and NSTEMI guidelines clopidogrel
should be given for the first 12 months if the 6 month mortality risk is > 1.5%
* Improves prognosis post MI
* Side effect: < 1% TTP usually 2 weeks after commencing the drug.
contraindications to Thrombolysis
- Active internal bleeding
- Recent hemorrhage, trauma or surgery (including dental extraction)
- Coagulation and bleeding disorders
- Intracranial neoplasm
- Stroke < 2 months
- Aortic dissection
- Recent head injury
- Pregnancy
- Severe hypertension
Dressler’s Syndrome:
This usually occurs 1 to 8 weeks after MI.
Presentation:
* Malaise, fever, pericardial pain
* Elevated erythrocyte count
* Sometimes may also have pleuritis and pneumonitis.
dressers syndrome
Treatment involves aspirin and analgesics. Corticosteroids and non-steroidal anti-inflammatory agents are best avoided in the first 4 weeks after MI as they delay myocardial healing. Aspirin in large doses is effective. Recurrences can occur, and in such cases colchicine is helpful.
ST Elevation Myocardial Infarction (STEMI) - In the absence of contraindications, all patients should be given
- Aspirin
- Clopidogrel: the two major studies (clarity and commit) both confirmed benefit but used different loading doses (300mg and 75mg respectively)
- Low molecular weight heparin
PCI
. Thrombolysis if not
Thrombolysis MI
Tissue plasminogen activator (TPA) has been shown to offer clear mortality benefits over
streptokinase
* Tenecteplase is easier to administer and has been shown to have non-inferior efficacy to
alteplase with a similar adverse effect profile
n ECG should be performed 90 minutes following thrombolysis to assess whether there has been a greater than 50% resolution in the ST elevation
* If there has not been adequate resolution then rescue PCI is superior to repeat thrombolysis
Coronary Angiography (CAG) complications:
Vascular complications: the most common complication overall is hemorrhage from access (right femoral artery mostly then right radial artery), much less common is rupture of coronary artery during revascularization or rupture of any artery from access to target artery
* Contrast Induced Nephropathy (CIN), higher incidence in diabetic patients and patients known to have renal dysfunction (prevented by good hydration)
* Cholesterol embolisation
* Arrhythmias (include arrest, ventricular and supraventricular) especially in primary intervention
(in case of acute MI)
* Reaction to contrast