Question

1. George has suffered a myocardial infraction

A. Explain to his non-medical oriented Family what has happened to his heart?

B. When you analyzed his ECG, you referred to several different leads such as lead I and lead III, what are leads?

C. Why is it possible to record an ECG on the body surface without direct access to the heart?

2. The following paragraph is a summary of a news paper article: A new treatment for atrial fibrillation due to an excessively rapid heart rate at the SA node involves a high-voltage electrical pulse administer to the AV node to destroy its autorhythmic cells. A ventricle pacemaker then implanted in the patient.

Briefly explain the physiological rationale of this treatment. Why is Rapid atrial depolarization dangerous? Why is the AV node destroyed in this procedure? Why must a pacemaker be implanted?

Answer 1

A) In simple terms myocardial term is refered to as heart attack, this condition occurs when one of the heart's coronary arteries is blocked suddenly or has extremely slow blood flow because of which  blood flow to the heart muscle is abruptly cut off, causing tissue damage.

B) Each lead is meant to pick up electrical activity from a different position on the heart muscle, so this allows an experienced interpreter to see the heart from many different angles, for example lead 1 to lead 4 , view the heart in the vertical plane, the information from these 12 leads is combined to form a standard electrocardiogram.

C) These are effective because electricity is conducted through body fluids to the skin surface and these impulses can be picked up by ECG recorder, and these information can be recorded, so ultimately the electrocardiogram can measure the rate and rhythm of the heartbeat, as well as provide indirect evidence of blood flow to the heart muscle.

2. Atrial fibrillation is an irregular and often rapid heart rate that can increase your risk of strokes, heart failure and other heart-related complications, sometimes medication wont work to correct this anomaly that time doctors might recommend a procedure to destroy the area of heart tissue that's causing the erratic electrical signals and restore your heart to a normal rhythm. (AV node controls the heart rate) A ventricular pacemaker is inserted to correct and restore normal heart beats.

Atrial depolarization can lead to a condition in which the heart beats with an irregular or abnormal rhythm,  Some arrhythmias are very dangerous and cause sudden cardiac death.