long QT syndrome 6

Long QT Syndrome Symptoms

A person with long QT syndrome may experience fast, erratic heartbeats when exercising or at times of emotional excitement. This can cause fainting (syncope) or seizures (fits). The symptoms are due to the abnormal electrical activity in the heart, which can lead to a potentially life-threatening arrhythmia called torsades de pointes.

• Fainting (syncope)
• Seizures (fits)
• Fast, erratic heartbeats during exercise or emotional excitement

These symptoms can be caused by the prolongation of the QT interval on electrocardiograms (ECGs) and a propensity to develop ventricular tachyarrhythmia torsade de pointes (TdP). [6][7]

Common Signs and Symptoms of Long QT Syndrome

Long QT syndrome (LQTS) can manifest in various ways, affecting individuals differently. Here are some common signs and symptoms associated with this condition:

• Fluttering feeling in the chest: This is a palpable sensation that can be felt by people with LQTS, often described as a fluttering or irregular heartbeat.
• Fainting (syncope): Fainting is one of the most common symptoms of long QT syndrome. It can occur suddenly and without warning, especially during physical activity or strong emotions.
• Gasping while sleeping: Some individuals may experience gasping or difficulty breathing while asleep, which can be a sign of LQTS.
• Near-drowning or drowning incidents: In some cases, people with LQTS may experience cardiac arrest or sudden death due to drowning or near-drowning incidents.
• Sudden cardiac arrest: This is a life-threatening condition that requires immediate medical attention.

It's essential for individuals and families affected by long QT syndrome to be aware of these symptoms and seek medical help if they occur. Early detection and treatment can significantly improve outcomes and prevent complications.

References: [6] (Fluttering feeling in the chest), [1] (Fainting), [4] (Gasping while sleeping), [5] (Near-drowning or drowning incidents), [8] (Sudden cardiac arrest)

Diagnostic Tests for Long QT Syndrome

Long QT syndrome (LQTS) can be diagnosed through various tests, including:

• ECG: An electrocardiogram (ECG) is the most common test used to diagnose LQTS. It records the electrical signals in the heart and shows how fast or slow the heart is beating [1].
• Genetic testing: Genetic testing is recommended for patients with a clinical or electrocardiographic presentation of LQTS, as it can identify the mutation responsible for the condition [5].
• Schwartz score: The Schwartz score is a diagnostic criteria used to determine the likelihood of LQTS. A score of ≥3.5 points indicates definite LQTS, while a score between 2 and 3.4 suggests an intermediate probability of LQTS [6].

In addition to these tests, a doctor may also perform:

• Physical exam: A physical exam is performed to assess the patient's overall health and identify any symptoms or signs that may be related to LQTS.
• Medical history review: The doctor will review the patient's medical history, including their family history, symptoms, and medications, to determine if they are at risk for LQTS [12].

It is essential to note that a diagnosis of LQTS requires a high level of suspicion, as the resting ECG may be borderline or normal in some cases [11].

Medicines Used to Treat Long QT Syndrome

According to various medical sources, people with inherited long QT syndrome often require treatment with medicines to manage the condition.

• Beta blockers: These medications, such as propranolol or nadolol, are commonly prescribed to help control heart rhythms and prevent abnormal heartbeats. [4][5]
• Other pharmacologic therapies: In some cases, other medications like potassium and/or spironolactone, mexiletine, may be used to manage the condition. [7]

It's worth noting that while medicines can help manage long QT syndrome, they are not a cure for the condition. A comprehensive treatment plan may also include lifestyle changes and, in some cases, surgical procedures or device implantation.

Conditions to Consider in the Differential Diagnosis of Long QT Syndrome

According to various medical sources, including [6] and [10], differential diagnosis for long QT syndrome (LQTS) should