What Is Paroxysmal Supraventricular Tachycardia?

Paroxysmal supraventricular tachycardia refers to tachycardia that originates in the atrium or atrioventricular junction. Most are due to reentry stimuli, and a few are caused by increased autonomy and triggered activities. The electrocardiogram is more than 3 consecutive premature ventricular beats called paroxysmal supraventricular tachycardia, which includes atrial and junctional tachycardia. Sometimes it is difficult to distinguish the two on the electrocardiogram. Tachycardia.

Basic Information

English name: paroxysmalsupraventriculartachycardia
Visiting department: Cardiology
Common locations: heart

Common causes: Coronary heart disease, myocardial infarction, hypoxemia, hypokalemia, pre-excitation syndrome, heart failure, chronic obstructive pulmonary disease
Common symptoms: Premature beat

Etiology of paroxysmal supraventricular tachycardia

Paroxysmal supraventricular tachycardia is common in coronary heart disease, myocardial infarction, hypoxemia, hypokalemia, preexcitation syndrome, heart failure, chronic obstructive pulmonary disease, other various organic heart disease, or Accompanied by atrial enlargement, digitalis or other drug toxicity, hyperthyroidism, etc., can also be seen without any cause, or due to emotional excitement, excessive fatigue, smoking, drinking induced.

Clinical manifestations of paroxysmal supraventricular tachycardia

1. Fast heart rate, 160-220 beats / minute, rhythm.

2. Heart palpitations or a strong heartbeat in the chest.

3. Polyuria, sweating, and difficulty breathing.

4. Long duration can cause severe circulatory disorders, causing angina, dizziness, syncope, and even heart failure and shock.

5. Sudden onset and sudden stop. When the onset is stopped, syncope may occur occasionally because the interval between recovery of sinus rhythm is too long.

6. Stimulation of vagus nerve endings can make 50% to 80% of PSVT abruptly abruptly.

7. Heart sounds are absolutely consistent, no artillery waves appear in the jugular vein. The pulse rate is small and blood pressure can drop.

In recent years, due to the research progress of cardiac electrophysiology, there is some new understanding of the mechanism and typing of paroxysmal supraventricular tachycardia. Generally divided into six types according to the different parts and mechanisms.

Paroxysmal supraventricular tachycardia

1. Three or more consecutive QRS waves appear on the electrocardiogram, with a frequency of 160 to 220 times / minute. The RR spacing is equal.

2. The 24-hour heart rate change of dynamic electrocardiogram is of great significance for the qualitative and quantitative diagnosis of arrhythmia in patients.

Differential diagnosis of paroxysmal supraventricular tachycardia

Clinically, it needs to be distinguished from sinus tachycardia, atrial flutter, and non-paroxysmal tachycardia.

Paroxysmal supraventricular tachycardia complications

Tachycardia frequency of more than 200 times / minute, can cause insufficient blood supply to the heart and brain organs, blood pressure drops, syncope, seizures (Alzheimer's syndrome), and angina, heart failure, and even sudden death.

Paroxysmal supraventricular tachycardia treatment

1. A method for stimulating vagus nerve endings. This method is mostly suitable for young people, not for the elderly. Ask the patient to hold their breath and exhale vigorously; Stimulate the pharynx and cause nausea; Shiatsu or massage the carotid sinus, try the right side for 10 seconds first, if it is invalid, try the left side for 10 seconds, do not press on both sides at the same time to avoid Causes cerebral ischemia. This method must be operated by a doctor; Shiatsu the eyeball, and then right and then left, no more than 10 seconds each time, do not use too much force, otherwise there may be a risk of retinal detachment.

2. Verapamil (Isodadine) is given intravenously. Patients who have not used beta-blockers for 2 weeks can be the first choice.

3. Piloside C (cedilan) should be preferred for those with PSVT and cardiac insufficiency, but those with preexcitation syndrome with QRS wave width should be disabled.

4. Amiodarone plus glucose solution, intravenous injection. The effect is faster than lanolin C (cedilan) and slower than verapamil (Isodridine), but the side effects are very few, because a considerable number of supraventricular tachycardia is reentrant through the atrioventricular node, and Intravenous amiodarone acts mainly on the atrioventricular node, so it can block PSVT.

5. Adenosine triphosphate (ATP) This drug has a significant inhibitory effect on the sinoatrial node and the atrioventricular node, and is effective for PSVT reentry through the atrioventricular junction. The drug has a short half-life of only 30 seconds, so if it is not effective, intravenous injection can be repeated after 3 to 5 minutes. In order to prevent severe sinus stagnation and atrioventricular block, intravenous injection with atropine can be combined. The elderly and sick sinus syndrome are disabled.

6. Speeding or paired pacing Those who fail to treat with various drugs can stop the tachycardia by speeding or paired pacing through the esophagus or atrium.

7. In emergency situations, such as acute heart failure, shock, etc., synchronous DC current cardioversion can be used under conditions.

8. Transcatheter radiofrequency ablation is safe and effective with few complications and can effectively treat most patients.

Prognosis of paroxysmal supraventricular tachycardia

No obvious organic heart disease, occasional attacks, no more than a few minutes each time, and no obvious symptoms, the prognosis is good, without special treatment. If there is organic heart disease, especially AMI complicated by PSVT, it is easy to cause heart failure and shock, and the prognosis is serious. It should be actively controlled.