ECG Flashcards
What should the time of the QRS complex be?
Less than 0.12s
What should the QT duration be? (Men and women)
Less than 0.45s for men and 0.47s for women
6 step ECG protocol?
Heart rate, heart rhythm, P wave?, PR interval, QRS complex, ST segment
What do variable RR intervals usually indicate?
Heart block
What should the duration of the P wave be?
Not more than 80ms
What is the range for the PR interval?
120-200ms
What conditions can PR prolongation be associated with?
Hypokalaemia, carditis, acute rheumatic fever
What could a long QRS complex indicate?
Slow ventricular depolarisation or part of the muscle not contracting normally
What does a long QTc indicate?
Risk of ventricular arrhythmias
What could an inverted T wave be a sign of?
Normal in children. CAD or PE in adults
What is ventricular tachycardia?
Ventricles taken over as pacemaker. Leads to poor cardiac output-> cardiac arrest risk
What is VF?
Irregular rhythm, no recognisable QRS. Can occur during or after MI, little or no cardiac output. Defibrillation required
What is first degree heart block?
Fixed constant PR over 200ms. Rarely causes problems on its own
What type 1 second degree heart block?
Wenkenback. PR gets progressively longer then resets. AV node problem.
What is type 2 second degree heart block?
P wave regular but AV nose randomly fails to respond- ventricular rate irregularly irregular.
What is third degree heart block?
No conduction between AV node and ventricles. P waves present but unsynchronised. Ventricular escape beats slow- bradycardia
What is AF?
Irregular contractions from ectopic pacemakers in atria. No P wave.
What are some symptoms associated with AF?
Sometimes none. Palpitations, fainting, chest pain, CHF. Exacerbated by exercise. Tachycardia
What is atrial flutter?
High but regular rhythm- around 300bpm. Circus excitation
What is junctional rhythm and what are the ECG signs?
Damage to SA node or block leads AV to take over. Absent P wave, bradycardia
What is supraventricular tachycardia?
Junctional rhythm but AV has hf circus excitation or ectopic- main symptom palpitations. Regular rhythm.
What is AVNRT?
AV node reentrant tachycardia. Type of SVT
What is bundle branch block?
Abnormal conduction through bundle branches. Prolonged QRS. Notch or double R wave.
What can ST depression indicate?
Coronary ischaemia or hypokalaemia.
What does ST elevation indicate?
MI often in LAD. In two or more adjacent leads.
