About long qt syndrome type 1

What is long qt syndrome type 1?

General Discussion

Romano-Ward syndrome is an inherited heart (cardiac) disorder characterized by abnormalities affecting the electrical system of the heart. The severity of Romano-Ward syndrome varies greatly from case to case. Some individuals may have no apparent symptoms (asymptomatic); others may develop abnormally increased heartbeats (tachyarrhythmias) resulting in episodes of unconsciousness (syncope), cardiac arrest, and potentially sudden death. Romano-Ward syndrome is inherited as an autosomal dominant trait.

What are the symptoms for long qt syndrome type 1?

Some people with long QT syndrome (LQTS) do not have any noticeable symptoms. The condition may be discovered when an electrocardiogram (ECG) or genetic testing is done for other reasons.

Fainting (syncope) is the most common symptom of long QT syndrome. A Fainting spell from long QT syndrome can occur with little to no warning. Some people have Fainting warning signs first, including:

Fainting occurs when the heart temporarily beats in an unorganized way. You might faint when you're excited, angry or scared or during exercise. Things that startle you — for example, a telephone or an alarm clock — can cause you to lose consciousness.

Long QT syndrome may also cause Seizures in some people. Symptoms of long QT syndrome sometimes occur during sleep.

Most people with symptoms of LQTS have their first episode by age 40. When the condition is present at birth (congenital long QT syndrome), symptoms may occur during the first weeks to months of life or later in childhood.

Generally, after a long QT episode, the heart returns to its typical rhythm. If the heart doesn't reset itself or if an external defibrillator isn't used in time to reset the heart rhythm, sudden death will occur.

What are the causes for long qt syndrome type 1?

Long QT syndrome is a heart rhythm disorder caused by changes in the heart's electrical recharging system. It doesn't affect the heart's structure.

In a typical heart, the heart sends blood out to the body during each heartbeat. The heart's chambers squeeze (contract) and relax to pump the blood. This coordinated action is controlled by the heart's electrical system. Electrical signals (impulses) travel from the top to the bottom of the heart. The tell the heart to contract and beat. After each heartbeat, the system recharges to prepare for the next heartbeat.

In long QT syndrome, the heart's electrical system takes longer than usual to recharge between beats. This delay is called a prolonged QT interval. It may be seen on an electrocardiogram (ECG).

Long QT syndrome is often grouped into two main categories, depending on the cause.

  • If you are born with the condition, it's called congenital long QT syndrome. Some forms of long QT syndrome result from altered DNA that is passed down through families (inherited).
  • If an underlying medical condition or medication causes it, it's called acquired long QT syndrome. This type of long QT syndrome is usually reversible when the underlying cause is identified and treated.

Causes of congenital long QT syndrome

More than a dozen genes have been linked to long QT syndrome so far. Researchers have identified hundreds of alterations within these genes.

There are two forms of congenital long QT syndrome:

  • Romano-Ward syndrome (autosomal dominant form). This more common form occurs in people who inherit only a single gene variant from one parent.
  • Jervell and Lange-Nielsen syndrome (autosomal recessive form). Episodes of this rare form of LQTS usually occur very early in life and are more severe. In this syndrome, children receive the altered gene variants from both parents. The children are born with long QT syndrome and deafness.

Causes of acquired long QT syndrome

More than 100 medications — many of them common — can cause prolonged QT intervals in otherwise healthy people.

If a medication causes acquired long QT syndrome (LQTS), the condition may be called drug-induced long QT syndrome. Medications that can cause LQTS include:

  • Certain antibiotics, such as erythromycin (Eryc, Erythrocin, others), azithromycin (Zithromax) and others
  • Certain antifungal pills used to treat yeast infections
  • Diuretics that cause an electrolyte imbalance (low potassium, most commonly)
  • Heart rhythm drugs (anti-arrhythmics) that lengthen the QT interval
  • Some antidepressant and antipsychotic medications
  • Some anti-nausea medications

Always tell your health care provider about all the medications you take, including those you buy without a prescription.

Health conditions that can lead to acquired long QT syndrome include:

  • Body temperature below 95 degrees Fahrenheit (37 degrees Celsius), a condition called hypothermia
  • Low calcium (hypocalcemia)
  • Low magnesium (hypomagnesemia)
  • Low potassium (hypokalemia)
  • Noncancerous tumor of the adrenal gland (pheochromocytoma)
  • Stroke or brain (intracranial) bleed
  • Underactive thyroid (hypothyroidism)

What are the treatments for long qt syndrome type 1?

Treatment for long QT syndrome (LQTS) may include lifestyle changes, medications, and surgery or other procedures.

The goal of LQTS treatment is to prevent erratic heartbeats and sudden death. Your health care provider will discuss with you the most appropriate treatment options based on your symptoms and your type of long QT syndrome. You may need treatment even if you don't often have symptoms.

If you have drug-induced long QT syndrome, stopping the medication causing the symptoms may be all that's needed to treat the condition. Your health care provider can tell you how to safely do so.

For other types of acquired long QT syndrome, treating the underlying condition is necessary. Treatment varies but may include magnesium or other fluids given by IV to correct electrolyte imbalances.

Medications

Medications won't cure long QT syndrome, but they can help protect against possible life-threatening heart rhythm changes.

Medications used to treat long QT syndrome may include:

  • Beta blockers. These heart drugs are standard therapy for most patients with long QT syndrome. They slow the heart rate and make long QT episodes less likely. Beta blockers used to treat long QT syndrome include nadolol (Corgard) and propranolol (Inderal LA, InnoPran XL).
  • Mexiletine. Taking this heart rhythm drug with a beta blocker might help shorten the QT interval and reduce the risk of fainting, seizure or sudden death.

Always take medications as directed.

Surgery or other procedures

Some people with long QT syndrome need surgery to control the heartbeat. Surgery or other procedures used to treat LQTS may include:

  • Left cardiac sympathetic denervation (LCSD) surgery. LCSD surgery is usually only recommended for people with long QT syndrome and persistent heart rhythm problems who can't take or tolerate beta blockers. It doesn't cure long QT syndrome, but it does help reduce the risk of sudden death. In this procedure, surgeons remove specific nerves along the left side of the spine in the chest. These nerves are part of the body's sympathetic nervous system, which helps control the heart rhythm.
  • Implantable cardioverter-defibrillator (ICD). An ICD is a battery-powered unit that's implanted under the skin near the collarbone — similar to a pacemaker. The ICD continuously monitors the heart rhythm. If the device detects an irregular heartbeat, it sends out shocks to reset the heart's rhythm. It can stop a potentially life-threatening arrhythmia.

    Most people with long QT syndrome don't need an ICD. However, an ICD may be recommended for certain athletes to allow return to competitive sports. The decision to implant an ICD, especially in children, needs to be carefully considered. Implanting an ICD is a major procedure and can result in inappropriate shocks and other complications.

What are the risk factors for long qt syndrome type 1?

The potassium ion channels in the heart do not function properly in long QT syndrome type 1, which causes interference with the electrical activity of the heart.

  • In people with LQT1, emotional stress or physical activity, especially swimming, can cause arrhythmias (abnormal heartbeats).
  • LQT1 patients are more likely to experience torsades de pointes, the most dangerous type of ventricular tachycardia.
  • Although those who have this condition may experience more arrhythmia episodes, these episodes typically end spontaneously and without medical intervention. This implies that the episodes have a lower risk of being fatal.
  • Being born deaf or partially deaf, taking drugs that are known to lengthen the QT interval experiencing extreme nausea or vomiting.
  • Having a medical history that includes thyroid disorders, bulimia, or anorexia nervosa can lead to developing LQT1.
  • Having a long QT syndrome-affected parent, sibling, or child.
  • Using drugs that have a history of prolonged QT intervals.
  • Excessive diarrhea or vomiting that depletes electrolytes.
  • Eating disorders that result in electrolyte imbalances, like anorexia nervosa.
Symptoms
Syncope,Blurred vision,Light headedness,Pounding heartbeats (palpitations),Weakness
Conditions
Arrhythmias,Torsades de pointes
Drugs
Mexiletine,Corgard,Propranolol

Is there a cure/medications for long qt syndrome type 1?

>A medical condition known as long Qt syndrome Type 1 (LQTS) interferes with the heart's regular electrical activity. The area of the electrocardiogram (EKG) trace that depicts the change in heart rhythm is referred to as the QT interval.

  • Long QT syndrome type 1 has no known treatment.
  • A medical professional will conduct a physical examination and inquire about your symptoms, medical history, and family history to determine whether you have long QT syndrome.
  • A stethoscope is used by the medical professional to hear your heart.
  • Tests to determine the rhythm of the heart can be performed if your doctor suspects you have an irregular heartbeat.
  • The treatment is to lower your risk of developing a heart arrhythmia by:

    •Taking beta-blocking drugs to slow down abnormally rapid heartbeats
    •Avoiding drugs known to lengthen the QT interval
    •Avoiding stressors like swimming or strenuous exercise
    •Taking Care of Acquired LQTS
    •Stop taking drugs that can accentuate patients' condition
    •Taking care of any underlying issues or deficiencies
    •Taking drugs to regulate heart rhythm (antiarrhythmics)
    •Placing an implantable cardioverter-defibrillator or pacemaker
Symptoms
Syncope,Blurred vision,Light headedness,Pounding heartbeats (palpitations),Weakness
Conditions
Arrhythmias,Torsades de pointes
Drugs
Mexiletine,Corgard,Propranolol

Video related to long qt syndrome type 1