paroxysmal supraventricular tachycardia
Introduction
Introduction to paroxysmal supraventricular tachycardia Paroxysmal supraventricular tachycardia refers to tachycardia originating from the atrial or atrioventricular junction, mostly due to reentry excitability, and a few are caused by increased self-discipline and triggering activity. Electrocardiogram continuous more than 3 times of supraventricular premature beats called paroxysmal supraventricular tachycardia, including atrial and borderline tachycardia, sometimes difficult to identify on both electrocardiogram, collectively referred to as paroxysmal supraventricular Tachycardia. basic knowledge The proportion of illness: 0.002% Susceptible people: adults, the elderly Mode of infection: non-infectious Complications: angina pectoris, hypotension, syncope, acute left heart failure in the elderly
Cause
The cause of paroxysmal supraventricular tachycardia
Cause:
Organic heart disease factor (40%):
Coronary heart disease, myocardial infarction, hypoxemia, hypokalemia, pre-excitation syndrome, heart failure, chronic obstructive pulmonary disease, and various other organic heart diseases can cause paroxysmal supraventricular tachycardia .
Drug toxicity (20%):
The toxicity of various drugs and the excessive use of digitalis drugs can lead to a series of symptoms, such as gastrointestinal reactions, nervous system abnormalities, visual changes, potassium metabolism disorders and arrhythmias.
Other factors (30%):
Infection, fever, hyperthyroidism, emotional agitation, excessive fatigue, smoking, drinking and other factors can induce the onset of the disease.
Prevention
Paroxysmal supraventricular tachycardia prevention
1. Prevention of predisposing factors
Common causes: overeating, indigestion, fever, fever, excessive intake of salt, blood potassium, low blood magnesium. It can be combined with the actual situation of the previous disease, sum up experience, avoid possible incentives, and is simpler, safer and more effective than medication alone.
2. Stable emotions
Maintain a calm and stable mood, relax and not be overly nervous. Avoid overjoy, sorrow, and anger. Don't watch nervous TV, ball games, etc.
3. Self-monitoring
Some arrhythmia often have aura symptoms. If you can find timely measures to reduce or even avoid arrhythmia. Some patients have developed a self-control method for their arrhythmia treatment, which can control arrhythmia with previous experience when it occurs.
4. Check your body regularly
Review the relevant items and rationally adjust the medication. Electrocardiogram, electrolytes, liver function, etc., because antiarrhythmic drugs can affect electrolyte and organ function. After medication, the patient should be reviewed regularly and the medication effect and dosage adjusted.
5. Reasonably arrange rest
Patients with arrhythmia should be guaranteed adequate sleep. It is not advisable to go to bed immediately after a meal. The sleeping position should be in the right lateral position and the legs should be flexed.
6. Pay attention to reasonable diet
The diet should be light and nutritious. Cooking with vegetable oils to reduce cholesterol intake. Eat more fresh fruits and vegetables. Eat a moderate amount of food, not too full.
7. Pay attention to moderate exercise
Patients with arrhythmia are not suitable for strenuous exercise. If chest tightness, chest pain, panic, shortness of breath, cough, fatigue, etc. occur, stop exercising immediately.
Complication
Paroxysmal supraventricular tachycardia complications Complications, angina, hypotension, syncope, acute left heart failure in the elderly
Ventricular paroxysmal tachycardia can cause dyspnea, angina pectoris, hypotension, oliguria and syncope . Attacks lasting more than 48 hours can lead to heart failure or cardiogenic shock, and some may occur due to surgical treatment. complication:
1, intraoperative complications
(1) Atrioventricular block (AVB) may occur during surgery. Lighter such as I degree AVB may not affect quality of life. If severe, such as III degree AVB, it needs to be treated, such as installing a permanent pacemaker, but there are also failures. Cases that are self-recovery with special treatment.
(2) Atrial fibrillation: You can try to use DC to switch.
2, postoperative complications:
(1) III degree AVB, can be treated with dexamethasone, terbutaline sulfate, or a permanent pacemaker.
(2) Pericardial tamponade: Postoperative pericardial tamponade Considering coronary sinus or coronary sinus malformation (such as hemangioma) when operating near the tricuspid valve during operation, the operation should be gentle and accurate, and postoperative blood pressure monitoring , ECG, if there is blood pressure drop, immediately find the reason, bedside color Doppler to assist in diagnosis, if there is a filling immediately pericardial puncture, drainage, and rehydration.
Symptom
Paroxysmal supraventricular tachycardia symptoms Common symptoms Chest tightness
Supraventricular paroxysmal tachycardia often manifests as a sudden onset, heart rate increases to 150-250 times per minute, may last for a few seconds, hours or days, palpitations may be the only symptom, but if there is a heart disease or Heart rate exceeds 200 beats per minute, may be weak, dizziness, angina, difficulty breathing or fainting. Ventricular paroxysmal tachycardia may cause dyspnea, angina, hypotension, oliguria and fainting. The diagnosis depends mainly on the following three points. :
(1) medical history, symptoms: sudden onset of symptoms, can be induced by exercise or emotional agitation, and there are many recurrent episodes. The medical history should ask whether ECG has been performed in the past. What is the result, and whether the ECG performance in non-existing period is too different? What is the efficacy of the drugs such as chlorpyrifos and cedilan.
(B) physical examination found: heart rate during the attack is more than 160-240 beats / min, fast and tidy, heart sounds powerful, no heart murmur, normal or slightly lower blood pressure.
(3) Auxiliary examination: ECG examination can confirm the diagnosis, QRS wave is ventricular-shaped, fast and tidy, and atrioventricular reentry (including dominant and recessive pre-excitation syndrome) mostly see retrograde P wave after QRS wave. There is no P wave after the QRS wave in the atrioventricular nodal reentry ventricular tachycardia. When the pre-excitation syndrome is bypassed or the supraventricular tachycardia is accompanied by a bundle branch block, the QRS wave broad deformity of the tachycardia is present, and the esophageal pacing is Most patients can induce supraventricular tachycardia, confirm the diagnosis, and can be initially typed.
Examine
Paroxysmal supraventricular tachycardia
It mainly relies on multi-lead ECG to confirm the diagnosis. The characteristics of ECG are as follows:
(1) The ectopic P wave is unclear, or atrial, or borderline, some without P wave, and some with retrograde P wave.
(2) The ventricular rate is often between 160 and 250 beats per minute. It can not be measured by pulse or cardiac auscultation.
(3) The RR interval is even and uniform on the electrocardiogram.
(4) The QRS complex is the same as the QRS waveform of normal sinus, with an interval of less than 0.10 seconds.
(5) There is a ST-T change, which is manifested as a change in myocardial ischemia.
Diagnosis
Diagnosis and diagnosis of paroxysmal supraventricular tachycardia
Can be diagnosed based on clinical performance and laboratory tests.
Differential diagnosis
(1) sinus tachycardia
The general heart rate rarely exceeds 150 beats / min, and is affected by breathing, exercise and body position. The electrocardiogram shows the presence of sinus P waves, which can help identify.
(2) atrial flutter and atrial fibrillation
An electrocardiogram can help identify.
(3) Paroxysmal ventricular tachycardia:
1 consecutive ventricular premature beats more than 3 times, QRS complex deformity, time 0.12 seconds, frequency rules or slightly irregular.
2 Sinus P wave has nothing to do with QRS. It is separated from the atrioventricular space. The P wave frequency is slow and buried in the QRS complex, so it is difficult to find.
3 Sometimes see the ventricular capture and ventricular fusion wave, the QRS complex pattern captured by the ventricle is close to normal, occasionally 1:1 room retrograde conduction, QR wave after the group has P ` wave, and has different degrees of room conduction Blocking, compression of carotid sinus heart rate unchanged, common in coronary heart disease, especially acute myocardial infarction and other organic heart disease patients, ECG can have characteristic changes of ventricular tachycardia, can help identify.
(4) Paroxysmal atrial tachycardia:
1 The rapid and regular heartbeat lasted more than 3 times, and its P wave morphology was abnormal.
2P-R interval > 0.12s.
The 3QRS complex is the same as the sinus.
4 atrial rate 160-220 times per minute.
5 Sometimes the P wave overlaps the T wave of the previous heart beat and is difficult to recognize, and may be accompanied by one or two degree atrioventricular block.
(5) Paroxysmal border tachycardia:
1 3 or more consecutive episodes of the atrioventricular junction, premature beats, frequency 160-250 per minute, rhythm rules.
The 2P` wave and QRS complex patterns have the characteristics of premature beats at the atrioventricular junction. The P` wave can be retrograde before, during or after the QRS complex, and may be accompanied by varying degrees of forward or reverse conduction block. Atrioventricular separation may occur at the same time or at different times.
