QT interval40.241 Definition: The QT40.241 interval is a measure of the time it takes for the heart to contract and relax, measured from the beginning of the Q wave to the end of the T wave on an electrocardiogram (ECG).
Normal values:
Men: 400-450 milliseconds (ms)
Women: 400-480 ms
Clinical Significance:
Prolonged QT interval: Longer-than-normal QT40,241 interval can increase the risk of dangerous cardiac arrhythmias, such as ventricular tachycardia with torsade de pointes (VTVT).
Short QT interval: Shorter than normal QT40.241 interval may be associated with an increased risk of atrial fibrillation.
Factors that influence the QT interval:
Gender (women generally have a longer QT interval than men)
Age (QT interval tends to increase with age)
Medicines (certain medicines can prolong or shorten the QT interval)
Underlying heart disease (such as heart failure or coronary artery disease)
Electrolytes (abnormal levels of potassium or magnesium can affect the QT interval)
Measuring the QT40.241 interval: The QT40.241 interval is measured on an ECG. The distance from the beginning of the Q wave to the point where the T wave returns to the baseline is measured.
Clinical Importance: Monitoring the QT40.241 interval is important for people who are at risk of cardiac arrhythmias, such as:
People with congenital long QT syndrome
People taking medications that can prolong the QT interval
People with underlying heart disease
Treatment: Treatment for a prolonged or short QT interval depends on the underlying cause. May include:
Changing medications
Cardiac monitoring
Implantation of an implantable cardioverter defibrillator (ICD)