The work of internal organs and body systems is guided not only by the central nervous system - the central nervous system, but also by the ANS (autonomic nervous system). The functioning of the heart also interacts in close connection with the ANS. With sympathetic and parasympathetic departments.
Manifestations of the functionality of the cardiovascular system
Important indicators of the functioning of the cardiovascular system are the pulse or heart rate and its changes in different circumstances, cardiac output and blood pressure.
The sympathetic division of the ANS is represented by fibers of the thoracic and cervical nodes. It tones the whole body: increases blood pressure (BP), speeds up and strengthens the heartbeat, regulates the cardiac output of blood into the aorta, dilates the pupil, speeds up breathing, causes a rush of blood to the skin, etc.
The parasympathetic division of the ANS acts exactly the opposite - the pulse is reduced, the pressure decreases, and cardiac output decreases. The influence of this department is due to the vagus nerve - the vagus. If the equilibrium of these divisions of the ANS is disturbed, VVD (vegetative-vascular dystonia) develops . Among its many manifestations, cardiac arrhythmias are present. With neurogenic origin, they are sinus and supraventricular. To assess the imbalance of these systems, various functional tests are used.
What it is?
Functional test is an integral part of medical control in the complex. She can talk about the presence of pathologies even before the onset of clinical symptoms. Such samples include the Ashner test - an eye-cardiac reflex.
The essence of the test is the increasing pressure on the closed eyeballs for a certain time, which causes reflex excitation of the parasympathetic division of the ANS, in particular, the vagus. It affects the blood vessels and heart, so the test is called the reflex. Application may be diagnostic in nature. But even in the treatment, the Ashner test is indispensable, for example, heart palpitations. When using this test, attacks of paroxysmal tachycardia stop. The patient himself can use this test, being a trained doctor. He exerts pressure on the eye sockets with his thumbs.
Ashner's test - symptoms and treatment
In the office for 15 minutes, the patient first rests on the couch while lying down. Then record his ECG for 1 minute - at rest, with the determination of the average heart rate (heart rate). After the initial ECG, the patient also determines the pulse. Without stopping the registration of the ECG, fingertips for 15-25 seconds apply pressure to the apples of the eyes until a slight discomfort appears.
I. I. Rusetskiy recommends pressing with the thumb and forefinger on the lateral surface of the eyeball, not on the front. His eyes are closed. Instead of fingers, pressure can be produced with weights of 30-40 g. After 20 seconds, at the end of the pressure, the average heart rate is determined for another 15 seconds. After that, the patient can be free.
Ashner test is a functional test. It is based on the fact that the tone of the vagus rises reflexively, and the reason for this is precisely the pressure on the eyeballs. Therefore, such a test requires caution, since the reflex excitation of the vagus can lead to rhythm disturbances - become atrioventricular, extrasystole may occur, and in some cases cardiac arrest for 30 seconds or more.
The Danyini-Ashner test (ocular reflex) for clinicians is important in that it can talk about the activity of the phase of the rheumatic process in rheumatic heart disease, even if there are no clinical symptoms. In children, the test is not applied.
Interpretation of Results
The results practically evaluate the type of nerve effects on the heart, and the list here is as follows:
- Normotonic type - the rhythm slows down only by 4-10 beats / min. Such an Ashner test is called positive.
- Vagotonic type - slowdown of the rhythm by more than 10 beats / min.
- Sympathicotonic type - the rhythm becomes more frequent, but does not slow down. The next point is to clarify the type of tachycardia. This is done on the basis of an ECG. In cases of sinus tachycardia, slowing of the rhythm is insignificant.
- With ventricular tachycardia, the rhythm does not change at all.
- With supraventricular, the rhythm either returns to normal or does not change. Inverted or distortion reaction - the pulse is increased by more than 4-6 beats. This is an increase in the sympathetic department. Such an Ashner test is called negative.
For therapeutic purposes, the test will be called effective if the heart rate has become correct on the ECG or subjectively. The test was proposed simultaneously by Danini and Ashner in 1908, therefore it is called the eye-heart test of Danini-Ashner.
Mechanism
In this case, the reflex arc starts from the fibers of the orbital branch of the trigeminal nerve, which are excited by pressure. Impulses are transmitted to the brain, where they switch to the centers of the vagus. And already he sends impulses to the heart muscle, leading to a decrease in heart rate, blood pressure and a decrease in cardiac output.
Cardiac indices after the end of pressure are normalized after a few seconds. This is normal. Otherwise, the patient needs further examination. An interesting fact is that the Ashner reflex occurs in children only on the 7th-9th day of life and has a normal or sympathicotonic effect.
Indications for
Ashner's test is often used not only by cardiologists and therapists, but also by neurologists. It is used for:
- Identification of the predominance of the tone of any department of the ANS, as mentioned above, this may be the influence of 2 departments.
- Differential diagnosis of tachycardia type.
- Reception can be used with a therapeutic purpose to relieve tachycardia. Then it can be carried out by the patient himself after clarifying the diagnosis of supraventricular tachycardia.
Contraindications to Ashner's test
Ashner's test cannot be carried out at:
- decompensated heart defects;
- decompensated heart failure;
- strokes and heart attacks;
- sharp arrhythmias;
- Pulmonary embolism (pulmonary embolism);
- aortic aneurysm;
- crisis of hypertension;
- general serious condition;
- acute infections with fever and bleeding;
- acute pathologies of the internal systems of the body;
- thrombophlebitis;
- atherosclerosis.
Ashner is also not taken if tachycardia is accompanied by additional dizziness, fainting, pain in the sternum, suffocation, and a drop in blood pressure. Then you just need to call an ambulance.
Ashner's test is undesirable because of the danger to apply to elderly patients, since they often have a violation of cerebral or cardiac circulation. Also, the test is contraindicated in myopia and eye pathologies.