In adults, a heart rhythm controlled by the sinus node at a rate of more than 100 beats per minute is called sinus tachycardia. It is the most common type of tachycardia and its occurrence is often associated with sympathetic excitation and decreased vagal tone. It is not a primary arrhythmia and can be caused by a variety of reasons. It can be caused by exercise, anxiety, emotional excitement during physiologic states, or it can occur after the application of drugs such as epinephrine and isoprenaline. It is highly likely to occur in the presence of fever, hypovolemia, anemia, hyperthyroidism, respiratory insufficiency, hypoxemia, hypokalemia, heart failure, and other cardiac disorders. The disease can be cured by controlling the primary pathology or predisposing factors, but is prone to recurrence
Causes
Tachycardia can be caused by exercise and emotional stress in healthy people. Alcohol, tea, coffee and drugs such as isoprenaline and atropine often cause sinus tachycardia. Common causes in disease states are fever, hypotension, hypoxia, cardiac insufficiency, anemia, hyperthyroidism and myocarditis. The etiology of sinus tachycardia is mostly functional, but can also be seen in organic heart disease and extracardiac factors. Its production is mainly related to sympathetic excitation and decreased vagal tone.
1. Physiological: Physiological sinus tachycardia is very common, and many factors affect the heart rate, such as changes in body position, physical activity, food digestion, emotional anxiety, pregnancy, excitement, fear, agitation, alcohol, smoking, tea, etc., which can increase the heart rate. In addition, age is also a factor, and children tend to have a faster heart rate.
2. Drugs: such as sympathomimetic drugs such as ephedrine, epinephrine. Parasympathetic blocking drugs such as atropine, caffeine, thyroxine, amphetamine can cause tachycardia.
3. Pathological: such as systemic diseases: hyperthermia, anemia, hypoxia, infection, hyperthyroidism, pain, acute rheumatic fever, beriberi and neurosis can cause tachycardia.
4. Cardiovascular diseases: acute blood loss, hypotension and shock, arteriovenous fistula, heart failure, myocarditis, cardiomyopathy, pericarditis, acute myocardial infarction, and a variety of organic heart disease can lead to sinus tachycardia.
Clinical manifestations
1. Palpitations, or sweating, dizziness, dizziness, fatigue, or manifestations of primary disease.
2. May induce other arrhythmias or angina pectoris.
3. Heart rate is mostly 100 to 150 beats/minute, most of the heart sounds are strong, or there are signs of primary heart disease.
Diagnostic basis
1. Heart rate is more than 100 beats/minute, mostly 100 to 150 beats/minute, and heart sounds are often strong. There may be signs of primary disease.
2. Electrocardiography: sinus rhythm: leads I, II, avF, V4-6, P wave upright;
avR lead, P wave inverted;
the rest of the leads P wave can be upright or inverted.
The P-wave morphology is normal, the P-R interval is greater than 0.12 seconds, and the frequency is greater than 100 beats/minute.
Treatment
Treatment principle:
1. Eliminate the causative factors and treat the primary disease.
2. Symptomatic treatment.
Principles of medication:
1. Most patients can disappear after eliminating the causes or triggers.
2. When there is a clear primary disease, it should be actively treated.
3. Symptomatic treatment can be given to beta-blockers or tranquilizers when symptoms are obvious, and then "B" or "C" can be used when "A" medicine is ineffective.
Evaluation of therapeutic effect
1. Cure: symptoms disappear after treatment, and the electrocardiogram returns to normal.
2. Improvement: the symptoms are reduced after treatment, the heart rate slows down but is still greater than 100 beats / min.
Complications
The disease is often caused by other diseases, so its complications are related to the cause of the disease, and the common complications are corresponding to acute pulmonary edema, heart failure, cardiogenic shock and other critical symptoms.
1, pulmonary edema
Pulmonary edema is an increase in the water content of the lungs due to the dysfunction of fluid exchange between blood vessels and tissues in the lungs. This disease can seriously affect respiratory function and is a more common clinical cause of acute respiratory failure. The main clinical manifestations are extreme dyspnea, sitting respiration, cyanosis, profuse sweating, paroxysmal coughing with a large amount of white or pink foamy sputum, symmetrical wet rales in both lungs, and butterfly-shaped flaky fuzzy shadows in both lungs seen on X-ray chest film, and shock or even death may occur in the late stage. Arterial blood gas analysis can have low O2, low CO2 partial pressure, severe O2 deficiency, CO2 retention and mixed acidosis in the early stage.
2, heart failure
Heart failure is divided into left heart failure and right heart failure. Left heart failure is mainly characterized by fatigue, dyspnea, initially exertional dyspnea, and eventually evolved into dyspnea at rest, can only sit and breathe. Paroxysmal dyspnea is a typical manifestation of left heart failure, mostly occurring during sleep, with chest tightness, shortness of breath, coughing, rales, especially severe may evolve into acute pulmonary edema and show severe shortness of breath, sitting breathing, extreme anxiety and coughing up mucus sputum containing foam (typically pink foamy sputum), cyanosis and other symptoms of pulmonary hemorrhage. Right heart failure is mainly manifested as lower limb edema, jugular vein rage, loss of appetite, nausea and vomiting, urinary oliguria, nocturia, and the phenomenon of separation of drinking and urination.
3, cardiogenic shock
Cardiogenic shock is a syndrome in which cardiac output is significantly reduced due to extreme cardiac decompensation and causes severe acute peripheral loop failure. Clinically, the main manifestations of severe underlying cardiac manifestations, physical circulation failure manifestations of persistent hypotension, oliguria, impaired consciousness, terminal cyanosis, etc., can also be combined with the manifestations of acute pulmonary edema and changes in hemodynamic indexes, i.e., arterial pressure <10.7KPa (80mmHg), central venous pressure can be normal or high, but the cardiac output is extremely low.
A sinus rhythm of 100 to 150 beats/minute is called sinus tachycardia. Sinus tachycardia is not a separate disease, at the onset of the first should try to avoid triggers, such as drinking strong tea, alcohol and the application of drugs that excite the heart to accelerate the heart rate. Keep your mood happy and prevent over-excitement and anxiety. If there is any cardiopulmonary or other systemic disease, it should be actively treated. For recurrent attacks, symptoms and affect the daily life and work, should be timely consultation, as soon as possible to identify the causes, in order to facilitate the prevention and treatment.