Cardio Flashcards
causes of MI
CAD, aortic stenosis, hypertrophic cardiomyopathy, tachyarrhythmias, cocaine use, anaemia, thyrotoxicosis
causes of cardiovascular non-ischemic chest pain
pericarditis, aortic dissection
causes of upper GI chest pain
gastro-oesophageal reflux disease, gallstones, peptic ulcers, pancreatitis
causes of respiratory chest pain
pulmonary embolism, pneumothorax, pneumonia, pleurisy
causes of musculoskeletal chest pain
costochondritis, Herpes Zoster, shingles
diagnosing visceral and somatic pain (in history taking)
visceral: diffuse, poorly localised
somatic: localised
def angina
discomfort in chest and/or jaw, shoulder, back, arm caused by myocardial ischaemia. most common cause in CAD
symptoms/characteristics typical angina
- discomfort in chest and/or jaw, shoulder, back, arm
- symptoms bought on by exertion
- symptoms relieved within 5 minutes (rest or GTN)
def atypical angina
chest discomfort that meets 2/3 characteristics of typical angina
risk factors for CAD
age, gender, diabetes, hyperlipidaemia, smoking, hypertension
def dyspnoea
shortness of breath
what do you look for on an ECG?
- heart rate
- rhythm (sinus-rhythm starting at the P wave): PR interval 120-200 ms
- axis: QRS complex upright
- QRS complexe: les than 120 ms
- Q waves
- isoelectric ST interval
- T waves: less than 5mm in height in limb leads and less than 15 mm in chest leads
- QT interval should be less than half the preceding RR interval
ECG indictions of CAD
- Q waves: more than 40 ms wide, 2 mm deep, 25% of depth of QRS complex, seen in leads V1-3
- Left bundle branch block: broad QRS (more than 0.12 sec), dip S wave in V1, no Q wave in V5/V6
- ST depression, T wave flattening or inversion
types of angina
stable, unstable, decubitus angina (lying flat), variant (prinzemetal) angina
ECG: difference between ischemic and infarcting endocardium
ischemic: depressed ST
infarcting: elevated ST + inverted T waves
branches of left coronary artery
Lad
circumflex
obtuse marginal
diagonal
branches of right coronary artery
right marginal
poster descending artery
venous drainage of heart
oblique vein of left atrium great cardiac vein left marginal vein posterior vein of left ventricle middle cardiac vein small cardiac vein --> coronary sinus
markers of cardiac cell death
troponin (T or I) 2-12 hours after MI (peak at 24-48 hours after MI) and can be elevated for up to 2 weeks post MI creatine kinase (non specific to cardiac cells)
Increase Proportionally to cardiac death and mortality
where are troponin T and I found in cells
actin filaments
causes of ventricular fibrillation
- IRRITABLE VENTRICULAR CELLS: Cad, electrolyte abnormalities (low Ca, high K, low Mg)
- SCAR: MI, cardiomyopathy (infection, genetic disorders, CAD)
- ELECTROCUTION
different types of Ventricular tachycardia
focal
reentrant
causes of focal vtach
cell irritation due to
- hormones
- low oxygen
- stretch
(CAD, electrolyte abnormalities)
causes of reentrant vtach
scar (MI, hypertrophic and dilated cardiomyopathy)