Making Sense of the ECG – Cases for Self Assessment, 2nd Edition PDF
What happens to our hearts when we get older? What does the electrocardiogram (ECG) tell us? How can we interpret these signals?
The human body changes as we age, and our hearts also change. Our bodies become less elastic and stiffen over time. This leads to a decrease in blood flow and oxygen supply to certain parts of our hearts. As a result, we start experiencing symptoms like fatigue, shortness of breath, dizziness, or even fainting spells. These conditions are known collectively as cardiac arrhythmias.
An ECG measures electrical activity inside the heart using electrodes attached to the skin. The ECG provides information about how well the heart pumps blood throughout the body. It shows whether the heart beats faster or slower and whether the heart has a normal rhythm.
ECGs are used to diagnose heart conditions. They can detect rhythm disorders, such as atrial fibrillation (AFib) and ventricular tachycardia (VT). These arrhythmias can cause sudden cardiac death. An ECG measures the electrical activity of the heart. It does this by placing electrodes on your chest. Your doctor may use these electrodes to record your heartbeat.
The first step in interpreting an ECG is to determine what type of recording you have. There are two types of ECGs: single-lead and multi-lead. A single lead records only one channel of information from the heart. This means that it cannot tell if there is a problem with the left side of the heart, right side of the heart, or both sides of the heart. Multi-lead recordings, however, measure multiple channels of information simultaneously. This allows doctors to get a better picture of the heart’s condition.
A normal ECG should show six waves of electrical activity. The P wave represents the beginning of each contraction of the atria (the upper chambers of the heart), while the QRS complex represents the beginning of the ventricles’ contractions. The T wave shows the repolarization of the ventricles after they’ve contracted.
An abnormal ECG has many different patterns. Some common ones include:
* Atrial fibrillation (Afib): In AFib, the atria fail to properly contract and instead quiver chaotically. This causes the ventricles to beat irregularly and out of sync with the atria. As a result, blood clots form and travel through the bloodstream. If not treated, these clots can lodge in the brain, causing strokes.
* Ventricular tachycardia: VT occurs when the ventricle contracts too rapidly. This results in an increased risk of having a stroke.