12-Lead Electrocardiogram (EKG) Practice Test 2025 - Free EKG Practice Questions and Study Guide

A prolonged QT interval is significant as it suggests an increased risk for ventricular arrhythmias. The QT interval represents the time it takes for the heart's electrical system to repolarize after each heartbeat. When the QT interval is longer than normal, it can lead to dangerous heart rhythms such as Torsades de Pointes, which is a form of polymorphic ventricular tachycardia that can result in sudden cardiac arrest.

This risk arises because the prolonged interval can indicate potential problems with the ion channels that regulate the heart's electrical activity. If the repolarization process is delayed, it can lead to disturbances in the heart's rhythm, contributing to the likelihood of arrhythmias.

In contrast, a normal range of QT interval indicates a healthy, well-functioning heart, while a shortened QT interval can also lead to arrhythmias, but a prolonged QT is specifically associated with a higher risk of life-threatening ventricular arrhythmias. Hence, understanding the implications of a prolonged QT interval is crucial for clinical assessment and management of cardiac health.