Sinoauricular or sinoarthrial blockade is a type of intracardiac conduction disorder. This condition is characterized by a slowed speed or a complete stop of the heart pulse to the atria from the sinus node. In this case, interruptions or sinking hearts, general weakness, short-term dizziness are felt.
There are many reasons why the sinus node stops. This requires a complete cardiological examination, since a failure in the rhythm does not occur just like that. It is the reason that determines the further treatment and prognosis of the disease.
In some patients, the heart works throughout its life in the rhythm of the atrioventricular junction or atrial rhythm. These backup sources provide adequate heart function. If they cannot cope with this, then there is only one way out - the implantation of a pacemaker.
Description of the disease
Sinoauricular blockade is a condition in which there is a weakness of the sinus node. Conducting an electrical impulse is blocked between the sinoarthrial node and the atria. With this violation, temporary atrial asystole is observed when one or more of the ventricular complex falls out.
Manifestations of sinoauricular blockade are rare, and if they develop, then most often in the male half of the population (in 65% of cases). The disease is determined at any age.
What is a blockade of 1, 2, 3 degrees and type? About it further.
Degrees and types of disease
The disease can be classified by severity. It happens the first, second and third degree:
- The first degree is difficult to determine an electrocardiogram. There is a rarer nucleation of cardiac impulses that fully reach the atria. The presence of sinus bradycardia may indicate blockade.
- But the second degree can already be determined by ECG. It is divided into 2 types. Sinoauricular block 2 degrees (type 1) - gradually blocking the heart, there are sudden episodes of complete loss of impulses. CA blockade of 2 degrees (2 types) - heart pulses fall irregularly, there are episodic and temporary complete blockades of the conduction. Some impulses do not reach the ventricles and atria. Samoilov-Wankerbach periods appear on the cardiogram. This suggests a sinoauricular block 2 degree 2: 1. One cardiac cycle falls out, with an increased RR interval equal to two main intervals. In some cases, every second impulse that follows normal contractions is blocked. This may mean allorhythmia.
- With the third degree of (complete) sinoauricular blockade on the ECG, the picture is as follows - all pulses from the sinus node are blocked. This most often leads to asystole and death. The driver becomes the atrioventricular node, the conducting systems of the atria and ventricles.
What is the reason for the blockade?
Sinoauricular blockade occurs with:
- organic myocardial damage;
- increased tone of the vagus nerve;
- defeat of the sinus node.
The disease is most likely to occur in a person who suffers from the following pathologies:
- heart disease;
- IHD (manifested by a heart attack, atherosclerosis);
- myocarditis.
We will name some more possible reasons for the development of the blockade:
- Adrenergic blockers, cardiac glycosides, drugs K, quinidine, which caused intoxication of the body.
- Defibrillation
- Reflex-increased tone of the vagus nerve.
Thus, various factors, which are often associated with the fact that cardiac activity is impaired, can lead to blockade of pulses in the sinus node. So, the development of this ailment occurs when:
- inflammatory processes in the right atrium;
- metabolic dystrophic disorders present in the atria;
- myocardial infarction;
- heart surgery.
Symptomatology
Sinoauricular blockade of the 1st degree is very difficult to identify, since it does not manifest itself in any way. It is determined only in the absence of subsequent cardiac contraction after 2-3 normal cycles.
The frequency of a sinus impulse affects the clinical signs of a second degree blockade. If infrequent prolapse of heart contractions occurs, then the patient will suffer:
- dizziness
- chest discomfort;
- general weakness;
- shortness of breath.
The symptomatology of the blockade, which is characterized by a certain absence of heartbeat cycles, will be as follows:
- sinking heart;
- noise in ears;
- bradycardia.
When the disease is accompanied by organic myocardial damage, heart failure forms.
Asystole leads to the development of Morgagni-Adams-Stokes syndrome in patients. At the same time, pale skin, unexpected dizziness, flickering of points in front of the eyes, cramps, loss of consciousness, ringing in the ears are observed.
So, we can conclude that the second and third stages are manifested:
- discomfort behind the sternum;
- bouts of dizziness;
- shortness of breath
- general weakness;
- prolapse of the heart;
- a sinking heart;
- pallor of the skin;
- tinnitus;
- cramps.
Diagnostic Methods
How to identify this ailment? It is known that sinoauricular blockade on the ECG is manifested. Is it so?
The main examination methods include:
- electrocardiography (ECG), since sinoauricular block is clearly visible on it;
- ultrasound of the heart (ultrasound).
The ECG results determine the presence and severity of SA. With 1 manifestations, there are almost no - only sinus bradycardia, which many people have and is considered a variant of the norm, is noted.
The first type of degree 2 blockade on the ECG is expressed as periodic rhythmic prolapse of the heart cycles (prolapse of the PP wave or the whole PQRST complex). In the second type, irregular and repeated prolapse of the PP wave, PQRST complexes, when 2 or more cardiac cycles disappear, pathological circulation forms.
So, electrocardiography has been performed, but it is important to distinguish between sinoauricular blockade and sinus bradycardia and arrhythmia, as well as atrial extrasystole, atrioventricular blockade of the second degree.
If sinus bradycardia is confirmed, then atropine tests are prescribed. After which, in patients, the heart rate doubles, and then it drops sharply also twice. This provokes a blockade. And in the case of normal operation of the sinus node, the rhythm will gradually increase. What is the treatment for sinoauricular blockade?
What is the therapy?
If a person has a sinoauricular blockade of the first degree, then no therapy is required. To restore normal cardiac conduction, it is necessary to cure the underlying disease or refuse to take medications that led to disturbances.
If vagotonia led to sinoauricular blockade of degree 2 of type 2, then the use of atropine subcutaneously or intravenously will be effective:
- To stimulate the automatism of the sinus node, sympathomimetics such as Ephedrine, Alupten, Izadrin are used.
- To improve the metabolism of the heart muscle, cocarboxylase, ribaxin, ATP are prescribed. In case of an overdose of these drugs, headache, nausea, tormenting insomnia, twitching of limbs, and vomiting can begin.
Reception of cardiac glycosides is contraindicated for patients, as well as treatment with beta-adrenergic blocking agents, quinidine-type antiarrhythmic drugs, K salts, cordarone, and rauwolfia drugs.
With a significant deterioration in the health of a patient with sinoauricular blockade, if asystole attacks often occur, doctors conduct temporary or permanent atrial pacemaker stimulation.
Blockade emergency care
Treatment consists in eliminating the cause that provoked sinoauricular blockade (such as intoxication with cardiac glycosides, rheumatism, coronary heart disease, etc.). Sometimes conduction can be restored only after treatment of the underlying disease or discontinuation of medications that caused its violation.
With frequent dizziness and a significant reduction in heart rate, a solution of atropine sulfate is administered subcutaneously, intravenously or in drops. Sometimes prescribed adrenomimetic drugs - Ephedrine and isopronyl radrenrenaline preparations.
"Ephedrine" is taken orally twice a day or subcutaneously as a solution.
"Orciprenaline" ("Alupent") is administered slowly intravenously, subcutaneously or intramuscularly or orally in tablets twice a day.
Isadrin (Novodrin) is a pill. Assign to take under the tongue (until completely dissolved) half a tablet three times a day or more.
An overdose of these drugs leads to headache, palpitations, trembling limbs, sweating, insomnia, nausea, and vomiting.
Preventive actions
All heart diseases should be detected in a timely manner. A disease such as sinoauricular block is still poorly understood, and therefore preventive measures do not exist as such. Basically, what should be done is to take care of eliminating the cause of the change in cardiac conduction. It should be regularly examined by a cardiologist (or arrhythmologist). Hypertension, obesity, unhealthy diet, bad habits, which include smoking and drinking alcohol, are also an increased heart risk.
What complications can this lead to?
The presence of negative consequences of sinoauricular blockade is explained by a slowed rhythm due to organic heart damage. Usually, the pathology described by us leads to chronic heart failure or worsens it, if it already exists, contributes to the formation of ventricular and ectopic arrhythmias.
What is the forecast?
Further manifestations of sinoauricular blockade are completely dependent on the cause, that is, on the underlying disease. The degree of conduction and the presence of other heart rhythm disturbances also play an important role.
In general, some kind of disturbance in hemodynamics does not cause a disease that does not manifest itself.
If Morgagni-Adams-Stokes syndrome occurs, the prognosis is unfavorable.