Dou shoot three-point wave nervousness and fainted? Can the sudden ringing of the phone make you dizzy and heartbeat? Don’t think it’s just an exaggeration. In fact, on average, one out of every 2,000 people suffers from long QT syndrome, which causes a lot of physical exertion during exercise, or emotional stress, fright, or sleep. Arrhythmia, sudden fainting, convulsions may occur Or even sudden cardiac arrest and sudden death! Some international studies have pointed out that for some patients with long QT syndrome, exercise is the main trigger for symptoms.
The heart itself has a system that stimulates current conduction to control and coordinate the contraction of the heart muscle, so that the heartbeat is regular and the heart can function normally. Long QT syndrome (LQTS for short) is a disease caused by a problem with the cardiac conduction system. It originates from the abnormal phenomenon of the microscopic pores of the ion channels in the cardiac muscle cells, which leads to the disorder of the cardiac current system. .
The current of the heart can be divided into different bands PQRST, and the interval between the Q and T bands is normally between 430 and 460 (milliseconds) according to age and gender. The risk of sudden cardiac death, due to the unstable current between the Q and T segments, causing premature beats (Triggered Beat), in this sudden abnormal heartbeat, the current will enter the circle of the heart and continue to circle, resulting in rapid heartbeat up to 250 to 300 strokes per minute. Due to the rapid heartbeat and the failure to effectively “pump blood to the brain”, it will trigger convulsions like epileptic seizures, or even cause the brain to become unconscious due to lack of oxygen.
Long QT syndrome is divided into congenital and acquired. Congenital is caused by the inherited genetic mutation, and acquired is caused by the influence of drugs or electrolyte disturbance. Some drugs such as: antihistamines, psychiatric drugs, heart and blood pressure drugs, antiepileptic drugs, flat headache drugs, antibiotics, antiviral drugs, diuretics, etc. can induce long QT syndrome.
The age of onset of congenital long QT syndrome is mainly under the age of 40. Many cases have their first onset at the beginning of puberty, but nearly half of them are clinically asymptomatic. However, if they are deaf at birth, or their family members have unknown reasons Fainting, sudden death, or blood relatives with long QT syndrome are considered high-risk groups and need to be paid more attention.
The American Heart Rhythm Society (HRS) and the European Heart Rhythm Association (EHRA) recommend that physicians, after reviewing the patient’s medical history, electrocardiogram (ECG) Q-to-T band length, and exercise stress test results, if there is a high suspicion of long QT syndrome, they should Do genetic testing for final diagnosis.
According to the gene mutations associated with long QT disease, 17 gene variants (subtypes) can be distinguished at present, and this gene classification is also helpful for understanding the disease. Among them, long QT syndrome types 1, 2, and 3 are the most common, accounting for 75% of congenital cases. In LQ1 patients, 68% of heart-related symptoms (eg, arrhythmias, fainting, and even death) are caused by exercise, especially swimming; in LQ2 and 3, exercise is caused Heart-related symptoms were 13% each. On the other hand, long QT syndrome type 2 is more likely to develop symptoms due to emotional stress and sound stimulation, while type 3 is more likely to have symptoms during sleep.
If patients with long QT syndrome are unconscious, they must use an automated external defibrillator (AED) for first aid. Since the survival rate drops by 7 to 10% every minute, it is recommended to get first aid within 5 minutes, and at the same time. Call emergency medical services to hospital.
Long-term treatment of long QT syndrome is mainly through drug therapy with beta-blockers, and surgical insertion of an implantable cardiac defibrillator (ICD) into the body to prevent arrhythmia and related symptoms. If necessary, the doctor may perform left heart sympathectomy (LCSD) according to the patient’s physical condition
In daily life, long QT patients who have implanted defibrillators need to reduce the risk of interference from external magnetic fields. Therefore, they should try to avoid contact with or stay away from high-voltage cables such as induction cookers and mountains. When using smart phones, mobile phones should also try to Stay at least 6 inches from your chest and answer calls with the other ear without a defibrillator.
In addition, patients with long QT syndrome should also avoid strenuous or other jerking exercises that are easily emotionally stimulated. Instead, they can take a moderate “slow” walk in the park accompanied by relatives and friends, or do some simple and not fast-paced gymnastics. Some sounds that are easily frightened, such as alarm clocks, phone ringtones, etc., should also be avoided. It is recommended to lower the volume or choose another softer ringtone. If you need to increase potassium intake in your diet, do not take related supplements or over-the-counter medicines without authorization, you should consult your doctor or pharmacist for guidance.
Most of the sudden cardiac death caused by long QT disease can be prevented and avoided, and early diagnosis can enable patients to make life changes and treatment, and greatly reduce the related risks.