Lecture 9 - ECG II

Question 1

Torsades De Pointes?

Answer 1

twisting of point on ECG, prolonged QT interval leading to arrhythmia

Question 2

Right Ventricular Hypertrophy diagnosis?

Answer 2

prominent deflections on most 12 point ECGs

Question 3

Myocardial ischemia main clinical relevance?

Answer 3

Hyperkalemia shortening AP duration due to lessened membrane potential - increased external K concentration causes increased K channel presence

Question 4

ECT signs of myocardial infarction?

Answer 4

altercations to T wave - initial rise in prominence (hypokalemia), acute ST elevation

Question 5

Reason for ST elevation?

Answer 5

ischemic zone of ventricle has depolarised resting potential causing a ECG baseline drop, rise to regular S in repolarisation level appears as ST elevation

Question 6

V1 -> V6 electrode reading progression?

Answer 6

greater R wave due to greater positive charge directed at electrode

Question 7

Waves and MI?

Answer 7

loss of R wave height progression @ lesion direction; late stage: no positive charge towards, only sligh negative charge away from positive electrode read causing negative - ‘pathological Q wave’