Angiocardiography and heart sounding
Heart probing and angiocardiography have a relatively small history. The idea of intravenous administration of medicinal substances directly into large veins was first expressed by the obstetrician-gynecologist Bleichreder in 1904. He proposed, for various septic diseases in the female genital area, to administer drugs directly into the lower vena cava and the aorta along a thin ureteral catheter conducted through the peripheral vessels of the lowerextremities. This technique the author experienced on himself.
In our experiment and clinic for the first time, Angiography SA Reinberg et al. Began to use
. Corrillos and Birnbaum in 1926 made the first attempt to obtain a contrast study of the cavities of the heart and large vessels by injecting a contrast agent directly into the peripheral vein.
Forssman, having previously experienced the introduction of a ureteral catheter into the heart in 1929, applied angiocardiography to the patient in 1931 by injecting a contrast medium through a catheter that was performed in the heart.
By their studies in the animal experiment, AE Plutenko and PN Mazaev have proved the real possibility of studying the anatomical correlation of the cavities of the heart and the main vessels with the angiocardiography method not only of
, but also of their functional state.
Since 1950, angiocardiography and heart sounding in the study of congenital heart defects and major vessels began to be widely used in the clinic headed by AI Bakulev. Subsequently, angiocardiography and heart probing questions were presented in the detailed monograph by E. N. Meshalkin, as well as in the works published from the clinic by P. A. Kupriyanov, B. V. Petrovsky, A. A. Vishnevsky, F. G. Uglov andetc.
Now various complex installations are offered, allowing to produce up to 200 X-ray images in one minute with an exposure of 1/18 second. The merits of these installations are unquestionable. However, as experience shows, in most cases it is quite enough to take 5-6 pictures with angiocardiography to clarify the nature of congenital heart disease. Such a number of images can be obtained using a tunnel cassette designed by GS Rukhimovich.
This cassette is available for production under normal conditions and is as easy to handle as possible. It is a flat box in which a movable metal frame( cassette holder) with a size of 32x165 cm is inserted. 6 regular cassettes 24x30 cm are freely placed on the cassette holder. Thus it is possible to get 6 pictures within 7-10 seconds.
Specifications for angiocardiography are as follows: current 80-110 mA, voltage 60-80 kv, exposure of each shot 0.15-0.2 seconds.
Venous angiocardiography should be performed in a special room in which an X-ray machine is equipped and a special table with a built-in tunnel cassette is installed. The tube of the X-ray apparatus irradiates the table from above. The patient is placed in the position on the back.
The research is conducted in accordance with the rules of asepsis.30 minutes before the study, the patient receives luminal in doses according to age. In 20 minutes, 2% pantopone solution and 0.1% solution of atropine sulphate are injected subcutaneously.
Under local anesthesia, 0.5% solution of novocaine secretes a vein of the elbow or shoulder vein. An indispensable condition is the use of a vessel that flows into the system v.basilica, not in v.cephalica, since when a contrast medium is introduced into the last vessel, the vascular of the scapula is filled and the contrast medium in an insufficient quantity enters the chambers of the heart and the main vessels. Under the isolated vein, two ligatures are introduced and after opening the lumen of the vessel, a cannula is inserted into it.
It is desirable to use a cannula with the widest possible lumen, otherwise it is impossible to obtain a rapid introduction of a contrast agent into the vascular bed, and this is necessary to obtain the proper concentration in the heart chambers and the main vessels. Only under this condition it is possible to obtain distinct angiocardiograms.
To avoid thrombus formation in the cannula and the nearest segments of the vein, it is necessary to slowly introduce into the lumen a physiological saline solution.
For angiocardiography, a Soviet preparation is used-70% or 50% cardiotrastic( an aqueous solution of an organic iodine compound).Before applying this drug, the sensitivity of the patient to iodine is checked. This is done by intravenous injection of one milliliter of cardiothorast on the eve of the study.
Cardiovascular for one study is taken from the calculation of 1 ml of 70% or 1.5 ml of 50% solution of this substance per 1 kg of the patient's weight.
Immediately after the rapid introduction of cardiothorac, a series of X-ray photographs is taken.
In the next few seconds after the introduction of a contrast agent in the vein, the patient has a feeling of heat, anxiety and shortness of breath. These phenomena usually pass quickly on their own. It is advisable in this period to give the patient breathe oxygen.
On the obtained X-rays it is possible to trace the progress of the contrast agent from the superior vena cava to the right atrium, right ventricle, pulmonary artery and return through the pulmonary veins to the left heart and aorta.
Aortography of .The study of the aorta and vessels leaving it is a much more complex and responsible study than angiocardiography through the venous pathway. Indications for this study should be determined with strict responsibility and this study should be applied in cases where it is impossible to obtain clarity of diagnosis in other ways. Aortography is a complex intervention and should be undertaken on special indications.
Prepare patients for aortography as well as for venous angiocardiography. With aortography in young children, general anesthesia should be preferred. The best is intratracheal anesthesia.
Currently, several methods of aortography are known. A number of foreign authors with aortography uses aortic or left ventricular puncture. Despite the comparative simplicity of this method, it can not be recommended for wide application, as it carries a serious danger. Doing aortography by puncture with a thin needle does not make sense, and using a needle with a wide lumen or, as recommended, a trocar is fraught with dangers of hemorrhage.
The choice for aortography of the brachial artery is also of little benefit, since the contrast medium must pass a relatively large path through the narrow vascular bed before entering the aorta. This does not allow you to get clear aortograms. However, carrying a probe( No. 10-12) through the brachial artery to the ascending aorta makes it possible to avoid the influence of blood flow and obtain a good contrast image of the aorta.
The most beneficial for aortography is the use of a common carotid artery. The caliber of this vessel is large enough, the path for passage of contrast medium to the aorta is minimal and straight.
Practically, aortography through the common carotid artery is performed as follows. The patient is placed on the operating table in the position on the back. Under the shoulders put a small cushion, the head tilts back slightly and turns to the right.
A 6-8 cm long incision is made along the anterior margin of the sternocleidomus muscle, receding upward from the left sternoclavicular joint by 2-3 cm. Dissect the skin, subcutaneous tissue and m.platysma. Opens the vagina of the sternocleidomusus muscle. The muscles are released from her vagina and delayed( this is done by the assistant) laterally. After that, open the back wall of the vagina of this muscle.
The jugular vein and the vagus nerve are also pulled laterally. A common carotid artery is excreted for 3-4 cm and under it is fed two thick( No. 5-8) ligatures or thin rubber tubes. After this, the common carotid artery is clamped with two clamps of Bleelok and between them the lumen of the vessel is opened in the transverse direction. In the lumen of the artery, a metal or polyvinyl chloride probe can be used to inject a contrast agent. We prefer to use the latter. At the outer end of the probe, put on a rubber tube, which before the introduction of contrast medium is clamped by a clamp. The probe is advanced to the aortic arch. To prevent bleeding, the walls of the vessel are pressed against the probe by means of previously supplied ligature. The position of the tip of the probe in the aorta is controlled by means of an X-ray screen. Before the introduction of contrast medium for a short period of time, open the lumen of the probe to check its patency, release air and blood clots from it.
Contrast substance is injected rapidly and under high pressure. At this point, do a series of X-rays. When the contrast medium is injected into the aorta, the right common carotid artery should be clamped to prevent massive deposition of it into the brain.
After extraction of the probe from the carotid artery, a continuous suture with atraumatic needles is applied to its wall.
Before sewing the lumen of the carotid artery, it is necessary to rinse it with a solution of heparin. Bleeding from the injection site usually stops on their own. In rare cases, you have to press these places with balls or napkins, moistened with thrombin and apply a hemostatic sponge to them. The surgical wound is sewn tightly.
Introduction of large amounts of concentrated solutions of iodine preparations directly into the vascular bed or into the heart chambers in contrasting examination of the heart and the main vessels carries many dangerous complications. Therefore, these studies should be carried out in the presence of appropriate indications and with the observance of a certain caution.
Dotter and Johnson collected in the world literature information concerning complications associated with the introduction of contrast agents in the vascular bed. According to their data, 36 deaths have been published in the world literature related to the introduction of contrast agents into the vascular bed. According to Morgan and Scott, mortality in angiocardiography is 1%( for 800 studies).Crawford on 2000 studies observed 6 deaths. In the clinic, headed by prof. Kupriyanov, there were 3 deaths per 1500 studies. Among the causes of death, the authors list the disorder of cardiac activity, respiratory failure, etc.
These complications usually occur within the next few hours and minutes after the introduction of a contrast agent into the vascular bed.
In some cases, hemorrhages in the cerebral cortex are observed.
Felten, who specifically studied the complications associated with angiocardiography, found that the most common are vomiting, tinnitus, dizziness, headache, itching, urticaria, dyspnea, laryngeal edema, respiratory arrest, circulatory disorders, collapse, etc.
Reynolds, in order to identify the causes of death in angiocardiography, studied the data of electrocardiography that were recorded during the study. The author has established that permanent electrocardiography during angiocardiography is a valuable auxiliary method, signaling about severe and dangerous complications. He believes that if changes in the electrocardiogram are detected before the injection of the contrast agent into the vasculature, which indicates conduction inhibition, then angiocardiography should be abstained.
Afi explains the occurrence of changes in the electrocardiogram by brief anoxemia of the myocardium caused by acute coronary insufficiency.
Lodin, Thoren, who studied renal damage in angiocardiography, found that these lesions are caused by the increased pressure that occurs when a contrast agent is injected into the vascular bed.
To prevent complications from the kidneys, these authors produce aortography only after a preliminary blockage of the spinal ganglia.
Heart probing .Heart sounding provides much valuable both for the diagnosis of congenital heart defects and for determining the degree of circulatory disturbance.
When probing the heart, it is possible to record pressure curves from the cavities of the heart and large vessels, to obtain blood for gas analysis, to record the electrocardiogram when guided away from the inner surface of the heart. Conducting a probe through pathological messages between the chambers of the heart and large vessels gives the most reliable information about the defect. However, this is not feasible in all cases. Nevertheless, the diagnostic value of heart probing is unquestionable. Heart sounding, as well as angiocardiography, is not a harmless operation, but involves some dangers. Therefore, strict testimony to the study must also be clearly defined and precautionary measures taken.
Preparation for heart probing is the same as for venous angiocardiography and aortography.
Anesthesia is usually local, general anesthesia is indicated only in small and restless children.
As probes, we use a variety of calibrated specially prepared PVC tubes. The caliber of the probe is selected according to the lumen of the vein. Its length varies from 50 to 70 cm.
The system for this study is assembled in such a way that a dropper with a bulb is connected to the probe to continuously supply liquid to the probe and the vascular bed, a water or, better, an electromanometer and a cannula for connecting the syringe to draw blood for gas analysis. For this purpose, glass tees and rubber tubes are successfully used. Instead of a three-way crane, we have recently successfully used glass tees.
The fluid supply flask is filled with saline solution to which a heparin solution is added at a rate of 5000 units per 250-500 ml of liquid.
Before probing, test tubes with vaseline oil and syringes are prepared, in which 1-2 ml of vaseline oil is also collected. This is done so that the blood taken for gas analysis does not come into contact with the air.
The patient is placed on the operating table in a position on the back in such a way that during the advancement of the probe it would be possible to follow it through the screen of the X-ray apparatus.
For the probing of the heart, the ulnar or brachial vein is usually used. To determine the defect of the atrial septum, it is better to use a large subcutaneous vein of the thigh through which the probe is guided into the lower vena cava and the heart chambers. Before opening the lumen of the isolated vein, slowly inject 5-10 ml of 0.5% solution of novocaine, which prevents spasm of the vein. Conducting a probe requires a certain skill. The first obstacle as the probe moves is found near the point of the subclavian vein entering the anonymous one. This obstacle is relatively easily overcome when the probe is rotated. Further from the unnamed vein probe freely passes into the upper vena cava and right atrium. The next obstacle is noted when the right atrial probe is drawn to the right ventricle. Here, difficulties are, as a rule, more significant. The tip of the probe often goes to the inferior vena cava or the probe in the right atrium makes a loop.
We managed to establish that the task of moving the probe from the right atrium to the right ventricle is greatly facilitated if, when the tip of the probe is brought to the right atrioventricular orifice, leave it in this position for 1-2 minutes. Over this period of time, in most cases, the probe tip is thrown from the atrium into the ventricle by a stream of blood. The same technique facilitates the movement of the probe from the right ventricle into the pulmonary artery. More often the probe from the main trunk of the pulmonary artery is guided into the right pulmonary artery. It is much less common in the left pulmonary artery.
The pressure recording on the probe path can be carried out either on its upward path or, conversely, on extraction. At each stage after recording the pressure, blood is taken for gas analysis and after that the probe clearance is washed each time with physiological saline solution containing heparin.
At the end of probing through the probe, angiocardiography can be performed.