What Is Long QT Syndrome?
The heart is divided into four chambers. The two upper divisions are the right and left atrium, and the two lower chambers are the right and left ventricles. Long QT syndrome or LQTS refers to a heart rhythm disorder that has the potential to be fatal. Long QT syndrome results in fast and chaotic heartbeats in either the ventricle or the atrium, which may trigger sudden episodes of unconsciousness as well as seizures. Rarely does long QT syndrome cause death.
Individuals born with genetic abnormalities and mutations may lead to long QT syndrome.
Certain drugs or nutrient imbalances may additionally cause long QT syndrome. Fortunately, long QT syndrome is treatable. One might need to avoid or take certain medications to prevent dangerous heartbeat episodes. At times, the treatment for long QT syndrome may require surgery. Management also encompasses limiting strenuous exercise with a sufficient intake of potassium. For patients who suffer from Long QT syndrome and who have survived an episode of cardiac arrest, the odds of death within 15 years is approximately 50 percent. This percentage dropped to one percent in 20 years with prompt treatment.
What Are the Types of Long QT Syndrome?
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Iron Channel Abnormalities: This is the most common type, including LQT1, LQT2, LQT3, LQT4, and LQT5.
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Jervell and Lange-Nielsen Syndrome: Both parents will be the carriers of the abnormal gene but will not show any symptoms of Long QT syndrome.
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Romano-Ward Syndrome: One parent will have the symptoms of Long QT syndrome, while the other will not. In this condition, the child has a 50 percent chance of acquiring the syndrome.
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Timothy Syndrome: This rare form affects other parts of the body, including the heart.
What Are the Signs and Symptoms of Long QT Syndrome?
There is an amplitude of people who suffer from long QT syndrome but show no signs or symptoms. They are generally those who have a congenital disability. Additionally, many of the below-mentioned symptoms occur during sleep. Nevertheless, some clinical manifestations point out the presence of long QT syndrome.
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Fainting.
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Loss of consciousness.
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Frequent heart palpitations.
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Generalized weakness.
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Seizures.
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Abnormal rhythm of the heart.
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Sudden death.
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Sudden emotional excitement.
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Cardiac arrest.
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A fluttering feeling in the chest.
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Mental stress.
What Are the Causes of Long QT Syndrome?
Long QT syndrome is caused by malfunctioning the heart's electrical conduction system. When the heart's structure is standard, it transfers blood to the body during each heartbeat while the four chambers of the heart contract and relax to pump the blood. The heart's electrical conduction maintains all of this coordinated action. After every heartbeat, the heart's electrical system recharges and prepares itself for the next heartbeat. In long QT syndrome, renewing the heart's electrical conduction network takes longer than usual. This delay causes the heart to stop working and can often be visualized on an electrocardiogram.
Mentioned below are some of the causes of long QT syndrome:
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Congenital long QT syndrome.
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An underlying medical or other cardiovascular condition.
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The autosomal dominant form of Romano-Ward syndrome (autosomal dominant state).
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The autosomal recessive form of Jervell and Lange-Nielsen syndrome.
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Antibiotics therapy such as Erythromycin and Azithromycin.
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Yeast infections.
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Antifungal medications.
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Antiarrhythmic medications.
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Low potassium levels.
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Antidepressants.
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Metabolic imbalance.
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Antiemetics.
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Low calcium level or hypocalcemia.
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Low magnesium level or hypomagnesemia.
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COVID-19 infection.
What Increases the Risk of Long QT Syndrome?
The following factors are known to increase the chances of developing long QT syndrome:
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Female gender.
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A family history of long QT syndrome.
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Personal history of cardiac arrest.
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Profuse vomiting and diarrhea.
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Eating disorders like anorexia nervosa cause electrolyte imbalance.
How to Diagnose Long QT Syndrome?
To diagnose long QT syndrome, the healthcare provider and team shall perform a vigorous physical examination and investigate the medical and family history. In addition, a routine heartbeat checkup through a stethoscope may also help in the early detection of long QT syndrome. A few of the tests that may be done to diagnose long QT syndrome are mentioned below.
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Electrocardiography.
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Ultrasound of the heart.
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Event monitor for the cardiovascular system.
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Holter monitoring.
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Genetic testing.
How to Treat Long QT Syndrome?
Early detection of long QT syndrome can avoid invasive treatment modalities. Medications are generally used to manage a case of long QT syndrome. Treatment depends on the severity of the condition; there are options for noninvasive drug therapy and invasive surgical corrections. The aim of treating a case of long QT syndrome is to avoid erratic and abnormal heartbeats that are currently the leading cause of unexpected death in patients suffering from long QT syndrome. Mentioned below are some of the ways long QT syndrome is treated:
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Beta-blockers and related medications.
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Anti-arrhythmic drugs.
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Surgical intervention such as left cardiac sympathetic denervation or LCSD.
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Implantable cardioverter-defibrillator or ICD.
What Are the Complications of Long QT Syndrome?
The following are the complications associated with long QT syndrome:
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Unexplainable fainting.
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Seizures.
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Ventricular fibrillation (rapid heart beating that causes the pumping function cessation).
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Torsades de pointes (a fatal condition characterized by twisting of points in the ECG due to rapid beating of the heart).
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Sudden death.
How to Prevent Long QT Syndrome?
Lifestyle changes such as eating a heart-smart diet, being physically active, regular exercise, and taking timely medication are necessary to avoid long-term QT syndrome.
What to Expect if a Person Has Long QT Syndrome?
With proper treatment methods, the death rate of people affected by long QT syndrome is one percent. When this condition is not treated, the prognosis is poor. About 21 percent of untreated people die within a year once they start to faint.
Conclusion:
Long QT syndrome, or LQTS, is a congenital heart disorder characterized by an elongation of the QT interval of the heart on an electrocardiogram. It results in a part of the heart beating extremely fast, called ventricular tachyarrhythmias, or a part of the heart beating extremely slow. It also causes a temporary pause in heartbeats. Over a period, all of these clinical manifestations tend to lead to syncope and cardiac arrest. If the case of long QT is left untreated, sudden death may occur. In rare situations, long QT syndrome is only diagnosed after a family member has a fatal episode of cardiac arrest. An electrocardiograph picks up the prolongation of the QT interval and thus is one of the best tools for diagnosing long QT syndrome. After the completion of treatment and correction of heartbeats, the patient needs to make an effort to modify their habits and lifestyle.