Murtagh - Chest pain cont. in adults Flashcards
features of pain of angina pectoris
oppressive discomfort rather than a pain
typically transient and lasts <10 mins
angina pectoris pain radiates to
mainly retrosternal and radiates to arms, jaw, throat, back
angina pectoris associated symptoms
shortness of breath, faintness, sweating
angina pectoris occurs during
exercise, emotion, after meals or in the cold
angina pectoris is relieved by
within a few minutes with rest
DDx of angina pectoris
mitral valve prolapse, oesophageal spasm, dissecting aneurysm
causes of angina
coronary artery atheroma
valvular lesions (aortic stenosis)
rapid arrhythmias
anaemia
rare causes of angina
vasculitis
trauma
collagen disease
what defines stable angina
pain occurs with exertion and is usually predictable with no symptoms change during the past month
what defines unstable angina
increasing angina (severity and duration) over a short period of time, precipitated by less effort and may come on at rest, especially at night
may eventually lead to complete infraction
it is due to unstable plaque
angina is also called
crescendo angina
pre-infarct angina
acute coronary insufficiency
nocturnal angina
pain occurs during the night
related to unstable angina
decubitus angina
pain occurs when lying flat and is relieved by sitting up
variant angina/prinzmetal angina/spasm angina
pain occurs at rest and without apparent cause
associated with typical transient ECG changes of ST elevation (as compared with classic changes of ST depression during efforts angina)
it can lead to infarction and cause arrythmias
caused by coronary artery spasm
how might angina show up on ECG
may be normal
may show ischaemia or evidence of earlier infarction
during an attack it may be normal or show well-marked depression of the ST segment, symmetrical T-wave inversion or tall upright T waves
is there a specific ECG of angina?
there is no specific ECG appearance typical of angina
all that can be said is that the ECG is consistent with angina
exercise ECG
should be perfomed if diagnosis of coronary artery disease is in doubt
a normal stress test does not rule out coronary artery disease
exercise thallium - 201 scan
helpful in some difficult circumstances such as the presence of left branch bundle block, old infarction and Wolff-parkinson-white (WPW) syndrome, when exercise test is of little use and with mitral valve prolapse (which gives false positive tests)
how does thallium - 201 scan work
thallium is only taken up by perfused tissue
gated blood pool nuclear scan
assesses the ejection fraction which is a reliable index of ventricular function and this aids assessment of patient for coronary artery bypass surgery
echocardiography is used to assess
global and regional wall motion abnormalities and assess valvular dysfunction and pericardium status
coronary angiography is used for
this test accurately outlines the extent and severity of coronary artery disease. it is usually used to determine the precise coronary artery anatomy prior to surgery
preventions of stable angina
no smoking
weight reduction
healthy eating
exercise
control of hypertension
control of diabetes
control of blood lipids
medical treatment for acute angina attack
nitrates (glyceryl trinitrate, isorbide trinitrate, nifedipine)
aspirin
if angina pain persists longer than 10 minutes despite two doses of nitrates
take a third dose and call an ambulance
tips for glyceryl trinitrate tablets
warn patient about headache and other side effects
take tablet sitting down
maximum 3 tablets in 15 minutes
tablets must be fresh
keep tablets out of light and heat
if the pain is relived quickly, spit the rest of the tablet out
you should avoid nitrates if
the patient has taken sildenafil or vardenafil in the previous 24 hours of tadalafil in the previous 5 days
to prevent angina pain in stable angina with regular predictable attacks precipitated by moderate exertion you should prescribe:
aspirin
beta blocker (metoprolol or atenolol)
nitrate (glyceryl trinitrate or isosorbide mononitrate)
unstable angina includes
onset of angina at rest
abrupt worsening of angina
angina following acute myocardial infarction
for variant angina (spasm)
use nitrates and calcium antagonist (beta blockers)
tolerance to nitrates
24 hour coverage with long-acting preparations is not recommended
the pain of myocardial infarction
variable, may be mistaken for indigestion
similar to angina but more oppressive
20% have no pain at all - high mortality rate
what kind of people have painless heart attacks q
silent infarcts
diabetics, hypertensives, males and the elderly
angor animi
fear of iminent death
aetiology of myocardial infarction
thrombosis with occlusion
haemorrhage under a plaque
rupture of a plaque
coronary artery spasm
signs of myocardial infarction
there may be no abnormal signs
- pale/grey, clammy, dyspnoeic
- restless and apprehensive
- variable BP with pain
- variable pulse, watch for bradyarrhythmias
- mild cardiac failure, third or forth heart sounds, basal crackles
Q wave ECG changes
broad >1mm and deep >25% length of the R wave
- occurs normally in leads AVR and V1; III (sometimes)
- abnormal if in other leads
- occurs also with WPW and ventricular tachycardia (VT)
- usually permanent feature after full thickness AMI
Q waves do not develop in subendocardial infarction
the strategies for management are based on
whether it is a Q wave (transmural) or non-Q wave (subendocardial) infarction
decision whether to use thrombolytic therapy
Q wave infarction has to be proven to benefit from thrombolytic therapy
non-Q wave infarction does not
T wave and ST segment ECG changes
transient changes (inversion and elevation respectively)
if there is new LBBB
think AMI (in LBBB no Q wave)
does a normal ECG exclude an AMI?
normal ECG does not exclude AMI
Q waves may take days to develop
cardiac enzymes during myocardial infarction
large infarcts produce higher serum enzyme levels
these include
Troponin I or T
Creatinine Kinase
troponin I and T
starts rising at 3-12 hours, peaks at 24 hours and persists for about 5-14 days
now the preferred test
positive in unstable angina
when else might troponin be raised
raised in aortic dissection and kidney impairment
is tropnonin useful for repeat MI
no
creatinine kinase
after delay of 6-8 hours from the onset of pain it peaks at 20-24 hours and usually returns to normal by 48 hours
CK-MB: myocardial necrosis is present if >15% of total CK
what is CK-MB
unlike CK, it is not affected by intramuscular injections
technetium pyrophosphate scanning
it is performed from 24 hours to 14 days after onset
it scans for hot spots - especially when a postlatedral AMI is suspected and ECG is unhelpful because of pre-existing LBBB
typical ECG features of myocardial infarction
typical evolution of ECG changes with myocardial infarction
