A rapid heart rate, medically termed tachycardia, occurs when the heart beats faster than its normal resting pace. This phenomenon arises from disruptions within the heart’s intricate electrical system, which orchestrates each heartbeat. When these electrical signals malfunction, they can trigger abnormal rhythms, causing the heart to accelerate. Understanding these various types of rapid heart rhythms is important.
Understanding Supraventricular Tachycardia
Supraventricular tachycardia, often referred to as SVT, is a rapid heart rhythm that originates in the upper chambers of the heart, specifically above the ventricles. This involves the atria or the atrioventricular (AV) node, a relay station for electrical signals. During an SVT episode, the heart rate can suddenly increase, often ranging from 150 to 220 beats per minute.
SVT is less severe compared to other types of fast heart rhythms. While it can be unsettling, it is not life-threatening for most individuals. Common symptoms during an SVT episode include a sensation of a racing or pounding heart, known as palpitations. Individuals may also feel lightheadedness, dizziness, or shortness of breath.
Understanding Ventricular Tachycardia
Ventricular tachycardia, or VT, is a fast heart rhythm that originates in the heart’s lower chambers, called the ventricles. These are the primary pumping chambers responsible for circulating blood throughout the body. When VT occurs, the ventricles beat very quickly and inefficiently, which can significantly reduce the amount of blood pumped to the body.
VT is a serious condition due to its potential to be life-threatening. It can lead to a substantial decrease in the heart’s pumping efficiency, potentially resulting in cardiogenic shock. In some cases, VT can degenerate into ventricular fibrillation, a chaotic rhythm that can cause sudden cardiac arrest. Symptoms of VT can be more pronounced than those of SVT, including fainting, severe dizziness, chest pain, and shortness of breath.
Differentiating SVT and VT: Are They Related?
SVT and VT are distinct types of abnormal heart rhythms, originating from different anatomical locations within the heart. This fundamental difference in origin means that SVT does not transform into VT. They are separate conditions with different underlying electrical pathways.
Confusion between the two can arise because both cause a rapid heart rate and may present with similar symptoms. On an electrocardiogram (ECG), some types of SVT can produce a wide QRS complex that might appear similar to VT. Despite these similarities, the electrical mechanisms driving each rhythm are different. Accurate diagnosis by a medical professional is necessary to distinguish between these two distinct arrhythmias and determine appropriate management.
When to Seek Medical Attention
It is important for individuals experiencing rapid heart rates or associated symptoms to seek timely medical evaluation. A healthcare professional can provide a proper diagnosis, often involving tests like an electrocardiogram (ECG) to assess the heart’s electrical activity.
Certain symptoms accompanying a rapid heartbeat warrant immediate medical attention. These include chest pain or discomfort, severe dizziness or lightheadedness, fainting, and significant shortness of breath.