sinus tachycardia



Overview

  • Adults in sinus rhythm with a normal rhythm but with a frequency of more than 100 beats per minute.
  • May be asymptomatic, or manifested as palpitations, chest tightness, shortness of breath, etc.
  • Causes include physiologic, disease, and pharmacologic factors.
  • Physiologic factors do not require treatment; drug or disease causes are mainly treated with general therapy and medication.
  • Definition

  • Sinus tachycardia is a sinus rhythm in adults with a normal rhythm but a frequency of more than 100 beats per minute. Sinus tachycardia is referred to as sinus tachycardia.
  • The frequency is mostly between 100 and 150 beats/minute.
  • Normal impulses originate from the sinus node, and the conduction pathway is “sinus node → inter-nodal bundle → atrioventricular node → Hippocampal bundle → right and left bundle branches → Purkinje fiber network”, thus forming a regular heart beat.
  • Abnormal impulses originating from the sinoatrial node can cause tachycardia, but abnormal impulses from other locations can also cause tachycardia, such as atrial tachycardia of atrial origin and ventricular tachycardia of ventricular origin.
  • Types

    Clinically, it is divided into physiologic sinus tachycardia and inappropriate sinus tachycardia.

  • Physiologic sinus tachycardia: common in healthy people.
  • Inappropriate sinus tachycardia: in the resting state, without clear physiological or pathological triggers, the heart rate continues to increase, or the increase in the heart rate is not related to physiology, emotional excitement, pathological state or drug effect level or inconsistent, also known as idiopathic sinus tachycardia.
  • Pathogenesis

    Sinus tachycardia is the most common cardiac arrhythmia and is experienced by essentially everyone.

    Etiology

    Causes

    Physiologic Factors

    Physiologic factors are a common cause of sinus tachycardia. Commonly found in healthy individuals, life, psychological, and environmental factors can have an impact on the heart rhythm.

  • Lifestyle factors
  • Drinking strong tea, coffee, alcohol, spicy and stimulating food, or hunger. With the digestion and metabolism of the diet, it can gradually return to normal.
  • Smoking, exercise, physical activity, etc. After stopping smoking or exercising, it can usually return to normal gradually.
  • Psychological factors: when emotionally excited, such as nervousness, anxiety, fear, etc.. When these emotions disappear, they usually return to normal gradually.
  • Environmental factors: Cold, heat, etc. Normalization usually occurs when the person returns to the comfort of a warm or cool environment.
  • Disease factors

  • Non-cardiac diseases: fever, infection, hyperthyroidism (hyperthyroidism for short), anemia, shock, etc.
  • Diseases of cardiac origin: acute myocarditis, pericardial effusion, myocardial ischemia, heart failure, etc.
  • Drug factors

    Application of adrenaline, ephedrine and other drugs.

    Triggering factors

    Sinus tachycardia can be induced by drinking strong tea and coffee, strenuous exercise and emotional excitement.

    Pathogenesis

  • Sinus tachycardia is a compensatory mechanism for the body to meet the needs of cardiac output in physiological and pathological conditions.
  • Idiopathic sinus tachycardia may be associated with increased autoregulation of the sinus node itself or abnormal autonomic regulation of the sinus node.
  • Symptoms

    The severity of clinical symptoms depends on the hemodynamic impact of the tachycardia and is related to the underlying cardiac status.

  • In sinus tachycardia with a heart rate of <120 beats/min, the volume of cardiac output is increased and the efficiency of the heart is increased, and clinical symptoms are generally asymptomatic.
  • If the heart rate is more than 120 beats/minute, there may be palpitations, chest tightness, shortness of breath, irritability and other symptoms, and even chest pain.
  • Consultation

    Department of Medicine

    Cardiovascular Medicine

    Routine physical examination reveals abnormal electrocardiogram results, or symptoms such as fatigue, palpitations, dizziness, blackouts, etc. It is recommended to consult the Department of Cardiovascular Medicine in a timely manner.

    Emergency Department

  • Sudden and severe palpitations and dyspnea, etc., it is recommended to go to the Emergency Department immediately.
  • In case of loss of consciousness, respiratory and cardiac arrest, immediately call 120 emergency number and perform CPR on the patient at the same time.
  • Preparation

    Preparing for your visit: registration, information preparation, common problems

    Tips for medical treatment

    Some sinus tachycardia may be occasional and no ECG abnormality may be detected during the examination. You can always record the triggering factors before the onset of symptoms to facilitate the doctor’s diagnosis.

    Preparation Checklist

    症状清单
  • What are the main symptoms?
  • What are the triggering and relieving factors for the symptoms?
  • How many times a day do these symptoms occur? How long do they last?
  • 病史清单
  • Is there a family history of the condition?
  • Are there any drug or food allergies?
  • Are there any other medical conditions?
  • What medications have you been taking recently?
  • Have you recently consumed strong tea or coffee?
  • Have you been overworked recently?
  • How is your sleep?
  • 检查清单
  • Specialized examination: electrocardiogram (including routine electrocardiogram, 24-hour ambulatory electrocardiogram, electrocardiogram exercise test, etc.), echocardiogram, coronary arteriogram, cardiac magnetic resonance examination
  • Routine tests: blood test, electrolyte test
  • Other tests: thyroid function test
  • 用药清单
  • β-blockers: propranolol, nadolol
  • Calcium channel blockers: verapamil, diltiazem
  • Other drugs: Ivabradine
  • Diagnosis

    Diagnosis is based on

    Medical history

    There are mostly clear physiologic or pathologic triggers.

  • Physiologic factors: drinking strong tea, coffee, strenuous exercise, emotional excitement, etc.
  • Pathological factors: fever, anemia, hyperthyroidism or acute myocarditis, etc.
  • Clinical manifestations

    Asymptomatic or with palpitations, chest tightness and shortness of breath.

    Laboratory tests

  • Routine blood tests: can clarify the presence of infection and determine the presence of anemia; fasting is not required before the test.
  • Thyroid function: for suspected hyperthyroidism, thyroid function test can be performed to clarify.
  • Electrocardiogram

  • P-wave is sinus.
  • In adults, the frequency of sinus P-wave is generally 100-150 beats/minute, and seldom exceeds 160 beats/minute.
  • Other tests

    Depending on whether sinus tachycardia is a manifestation of other diseases (e.g., heart failure, anemia), further relevant examinations for the primary disease need to be improved.

    Differential Diagnosis

    Sinus tachycardia.

  • Similarities
  • Both may have palpitations, shortness of breath, chest tightness and other manifestations.
  • The morphology of P wave is also the same.
  • Differences
  • Sinus tachycardia: the onset is gradual and often lasts for a long time; stimulation of the vagus nerve can temporarily slow down the sinus rate, but it cannot be terminated.
  • Sinus tachycardia: often induced by atrial pre-systole, sudden onset and off, shorter duration; stimulation of the vagus nerve can terminate the sinus tachycardia, after termination of the compensatory interval is the same as the sinus cycle.
  • Focal atrial tachycardia

  • Similarities
  • Both may be characterized by palpitations, shortness of breath, and chest tightness.
  • When the point of agitation of atrial tachycardia is close to the sinus node, the morphology of atrial P-wave may be close to that of sinus P-wave.
  • Differences: Focal atrial tachycardia is not induced by atrial pre-systole, and there is a characteristic “warm wake-up” (gradual acceleration) at the beginning of the attack, deceleration before termination, and atrial fusion wave can be seen when the frequency is slower. In atrial tachycardia, the “P” wave is different from the sinus “P” wave on electrocardiogram.
  • Treatment of atrial tachycardia

    Principles of treatment

  • The first step is to find the cause of the disease.
  • Physiological factors do not require treatment; disease or drug-induced patients need to be treated for the cause, and if necessary, appropriate drugs should be chosen to control tachycardia, and radiofrequency ablation can be considered to control the heart rate when drugs are ineffective.
  • General treatment

  • Improve life habits, do not drink or drink less strong tea, coffee, etc..
  • Discontinue the drugs that induce tachycardia.
  • Treat diseases that cause tachycardia such as heart failure, infection and hyperthyroidism.
  • Medications

    Beta-blockers

  • Can control heart rate and relieve tachycardia symptoms.
  • Used in combination with myocardial ischemia, without contraindications such as bronchial asthma, acute heart failure, chronic obstructive pulmonary disease (COPD).
  • Commonly used drugs: propranolol, metoprolol, atenolol, bisoprolol and carvedilol.
  • Idiopathic sinus tachycardia is mostly poorly responsive.
  • Non-dihydropyridine calcium channel blockers

  • Can be used alone or in combination.
  • Idiopathic sinus tachycardia tends to respond poorly to them.
  • Ivabradine

    Can be used alone or in combination with beta-blockers.

    All drugs should be used in accordance with medical advice and should not be adjusted or discontinued on their own.

    Radiofrequency ablation

  • Radiofrequency ablation can be considered to improve the function of the sinus node if drug treatment is ineffective and symptoms are significant.
  • Radiofrequency ablation can be performed in the head of the sinus node, so that the autoregulation point of the sinus node is shifted downward, and sinus rhythm can be expected to slow down.
  • Prognosis

    Cure

  • Physiologic factors usually do not require treatment.
  • The prognosis depends on the severity of the underlying co-morbidities.
  • Hazards

    Idiopathic sinus tachycardia has no known cause, and persistent abnormal heart rate increases can lead to cardiomyopathy and heart failure.

    Daily

    The following section focuses on patients with sinus tachycardia due to disease-related factors.

    Daily management

    Dietary management

  • Ensure adequate intake of protein, unsaturated fats, vitamins, minerals, dietary fiber, and water. Soy products, dairy, lean meat, fish (may be 1~2 times per week), fresh fruits, fresh vegetables and nuts may be chosen.
  • Control sugar intake appropriately, and choose cereals and potatoes instead of refined rice and noodles.
  • Avoid diets high in salt and fat. Control salt intake to less than 5 grams per day, and avoid deep-fried, pickled and barbecued foods.
  • Avoid raw, cold, hard or too hot food, chew slowly and avoid overeating.
  • Eat less irritating food such as chili, coffee, strong tea and mustard.
  • Exercise management

  • Exercise appropriately, choose sports such as brisk walking, jogging, playing tai chi, swimming, square dancing, cycling, etc., or choose sports according to the doctor’s instruction.
  • Exercise in moderation and avoid excessive exercise.
  • If you feel uncomfortable during exercise, stop immediately and take a rest.
  • Work and rest management

    Regular work and rest, ensure enough sleep and avoid staying up late.

    Others

  • Safety: If dizziness occurs, sit down or lie down immediately to avoid falling.
  • Quit smoking and stay away from second-hand smoke.
  • Stop drinking alcohol.
  • Disease monitoring

    If the original symptoms do not improve, or new symptoms appear, consult a doctor promptly.

    Prevention

    The following is intended for patients with sinus tachycardia caused by disease.

  • Actively treat the original disease.
  • Use medication appropriately: follow your doctor’s instructions. If there is any discomfort during the use of medication, it is necessary to consult a doctor promptly.
  • Reasonable diet to prevent heart disease.
  • Improve dietary structure to ensure adequate nutrition; avoid overeating and maintain appropriate body weight.
  • Avoid diets high in salt, sugar and fat, and try to avoid pickled, smoked, barbecued and fried foods.
  • Eat less stimulating foods, such as chili peppers, coffee, strong tea and mustard.
  • Eat more foods rich in dietary fiber, such as whole grains, fresh vegetables and fruits, etc. Food types should be diversified and alternated.