Overview.
Persistent junctional reentrant tachycardia (PJRT), also known as persistent junctional recurrent tachycardia (PJRT) and persistent junctional tachycardia (PJRT), is an unrelenting junctional tachycardia characterized by a narrow QRS waveform with retrograde P-waves, an R-P interval that is longer than the P-R interval, and persistent, recurrent episodes of tachycardia.PJRT is most often observed in children and is usually persistent and prone to arrhythmogenic cardiomyopathy, or tachycardia. PJRT is most common in children and is often persistent and can develop into arrhythmogenic cardiomyopathy (or tachycardia).
Etiology
At present, there is no organic heart disease in patients with persistent junctional tachycardia, but some patients may have prolonged recurrent episodes of tachycardia, resulting in decreased cardiac function, or even the development of cardiomyopathy and cardiac enlargement.
Symptoms
1. Early age of onset, mostly seen in children and young people. Because of its early onset, PJRT is most common in children and can continue into adulthood.
2. Tachycardia is persistent and recurrent, and is often difficult to control with medication. The episodes can last for several months.
3. Because of the prolonged recurrent episodes of tachycardia, cardiac function decreases and even develops into cardiomyopathy and heart enlargement.
Examination
1. Electrocardiography
(1) PJRT is often induced by critical shortening of the sinus cycle, atrial pre-systole, and ventricular pre-systole Sinus cycle change induces or terminates supraventricular tachycardia, which is the main feature of this disease. It is often a gradual acceleration of sinus rhythm followed by PJRT.
(2) There is no prolongation of the first P-R interval at the onset of the tachycardia.
(3) The tachycardia continues to recur with several sinus beats in between.
(4) The P wave is negative in leads II, III, and aVF and positive in lead aVR The reason for this is that the atrioventricular connection of the atrioventricular bypass is below the orifice of the coronary sinus, which corresponds to the right posterior septal area. It is the reverse conduction branch of the atrioventricular bypass in tachycardia, so the wave is reversed in the above leads.
(5) Because of the slow conduction of the bypass, the P wave is far away from the R wave, forming a long R-P interval and a short P-R interval.R-P/P-R>1, but there are cases in which the R-P interval is slightly shorter than the P-R interval or the R-P interval=P-R interval.
(6) Normal ECG during interictal period Normal P-QRS-T waveform and normal P-R interval. No preexcitation pattern.
2. Electrophysiologic examination
Electrophysiologic characteristics prove that the insidious atrioventricular bypass with slow conduction and decreasing conduction is the electrophysiologic basis of PJRT. The atrioventricular bypass is the retrograde branch of the tachycardia refractory loop, and the AV node is the anterior branch.
The site of an occult atrioventricular bypass with slow conduction and decremental conduction characteristics: the classical site is the coronary sinus orifice (posterior septum), but it can also be located in other sites, such as the right atrial free wall, the right anterior septum, the left posterior septum, the left free wall, the right posterior wall, the left posterior wall, and the left posterior wall.
Diagnosis
1. Tachycardia is persistent and recurrent and difficult to control by drugs.
2. The surface electrocardiogram showed supraventricular tachycardia with 1:1 atrioventricular conduction.
3. Intracardiac electrophysiologic specimens showed that the Hirschsprung A wave was later than the first excited retrograde A wave, and the earliest VA interval was >110 ms.
4. In tachycardia, ventricular stimulation during the Hirschsprung’s bundle off-phase can capture the atria earlier, the earliest site of atrial agitation is mostly at the coronary sinus orifice, and the order of atrial retrograde agitation remains unchanged.
5. The VA interval showed decreasing conduction during ventricular programmed stimulation, prolonging >50ms.
6. There is no prolongation of the AH interval (P-R interval) before the attack.
7. Catheter-based radiofrequency ablation is curative.
Treatment
1. Drug therapy
Effective for some patients. All kinds of antiarrhythmic drugs can be chosen, and when the efficacy is poor, amiodarone, flecainide or a combination of the two can be chosen. During drug treatment, attention should be paid to the control of other factors that aggravate arrhythmia, such as heart failure, electrolyte disorders, endocrine diseases, myocarditis, myocardial ischemia and so on.
2. Catheter radiofrequency ablation
It can be cured radically, with good efficacy and few adverse effects, and should be the first choice. After completing the electrophysiological examination, a large head ablation electrode catheter is inserted, marked near the mouth of coronary sinus, looking for the earliest site of atrial agitation for ablation, each time the discharge is 20-30W, the trial discharge is 10s, and if it is effective, then the discharge is continued for 60s; if the trial discharge is ineffective, then it is re-marked to change the site of ablation until it is successful.
Prognosis
PJRT is most common in children and is often very persistent and prone to develop into arrhythmogenic cardiomyopathy (or tachycardia). If it does not recur after catheter-based radiofrequency ablation, it is considered cured and has a good prognosis. If tachycardia occurs for a short period of time, the tachycardia can be cured and return to normal. If the time is long, it is difficult to return to normal. Therefore, diagnosis and radical treatment must be timely, as soon as possible, as soon as possible.