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The paper discusses the potential possibility and effectiveness of X-ray endovascular laser recanalization (ELR) of the coronary arteries in order to treat coronary atherosclerosis in patients with coronary heart disease. The intervention was performed in 4 patients (into the anterior interventricular artery in 3 and into the right coronary artery in 1). In 3 of 4 cases, X-ray ELR proved to be successful, in one case the intervention failed due to technological reasons. Recanalization of a completely occluded segment of the coronary artery with a residual stenosis of no more than 40% was observed in two cases. Laser recanalization of profound local coronary stenosis was made in the mid-third of the vessel in one case. It can be stated that X-ray ELR of the coronary artery may extend the scope of X-ray surgical therapeutical tools of the treatment of coronary atherosclerosis. At the same time, accumulation of clinical experience and further improvement of laser and laser catheter engineering are essential in defining the value and possible scope for the application of this method.

The work discusses the results of intraoperative laser recanalization (LR) of the coronary arteries (CA). It is shown that the method facilitates increase of the degree of myocardial revascularization after a combined operation--aortocoronary shunting and intraoperative CA LR. The intervention was carried out on 10 patients, in 9 of them retrograde CA LR was conducted for recanalization of proximal affection of the CA and one patient underwent retrograde LR of a distally occurring stenosis of the anterior interventricular artery. Among the 10 interventions 7 were successful: in 5 patients the narrowed CA lumen was completely restored without residual stenosis, in 2 patients the stenosis reduced by 50-60% with a residual stenosis of no more than 30-40%. Perforation of the CA wall occurred in 2 cases and was repaired surgically. Still in another case an attempt to perform laser recanalization of the right CA failed because of technical reasons. Reocclusion of the recanalized CA segment was encountered in the late-term period in 2 of 4 patients. The conclusion may be drawn that CA LR is an effective auxiliary method in the formation of an aortocoronary shunt. The presence of diffuse, multiple lesions of the shunted CA and occlusion of the vascular lumen, affection of the distal arterial channel of the CA are the main indications for the use of intraoperative CA LR.

The causes of angina pectoris recurrences after aortocoronary bypass surgery have been studied. Indications for repeated myocardial revascularization and the possibilities for its performance have been analyzed. The long-term results of aortocoronary bypass surgery performed in 358 patients were evaluated at 30 months, on the average, after the operation. A gradual rise in the rate of angina recurrences was noted mostly within the first postoperative year. Repeated coronary angiography with bypass contrasting was done in 100 patients, 37 of whom presented angina recurrence. Impaired patency of the aortocoronary bypass was found to be the major cause of a recurrence (83.8%), this could be secondary to bypass thrombosis, fibrous hyperplasia of the graft intima, and atherosclerosis. Among other causes were incomplete revascularization of the myocardium and progression coronary atherosclerosis. All patients with pronounced angina pectoris were recommended repeated coronary angiography with bypass contrasting to specify indications for operation and possibilities for its performance. It was noted, that repeated revascularization may be hindered not by a factor responsible for the current recurrence, but primarily by the poor status of the distal portion of the diseased arteries due to diffuse atherosclerosis.

Anatomo-morphologic and clinico-angiographic peculiarities of the internal thoracic arteries have been considered in the article. The assessment of these arteries is of great importance for defining the indications for the use of these vessels in revascularization of the myocardium. It has been found that mammary-coronary anastomosis is indicated for the patients at the age up to 55, and the branches of the left coronary artery are the most suitable for direct mammary-coronary anastomosis.

Examination covered 56 patients with chronic post-infarction aneurysm of the heart. It included electro- and phonocariography, selective coronarography and ventriculography of the left heart. In the majority of these patients the affection started with myocardial infarction which gave rise to the development of the cardiac aneurysm. Coronarography disclosed a lesion of the left anterior descending artery in the form of an extended occlusion. Collateral coronary circulation was indefinable. Ventriculography of the left heart disclosed an aneurysm whose localization accorded with electrocardiographic indications. In the development of aneurysms of the heart the authors attach great importance to presence of collateral circulation at the instant of an acute lesion of the coronary artery.

An examination was made of 38 patients undergone aortocoronary bypass surgery. Comparing the density of content in the aorta and shunt before and after bolus contrast in computerized tomography makes it possible to evaluate the patency of the aortocoronary shunt. A shunt patency coefficient (SPC) was proposed, which fitted the ratio of density differences in the shunt to those in the lumen of the ascending aorta before and after the injection of a contrast agent. SPC equal to 0.5 or more is indicative of a good patency of the aortocoronary shunt, but that being 0.3 or less suggests no or extremely poor function of the shunt. SPCs that are equal to 0.3-0.5 are transient indicators of its patency.

Thirty patients with coronary heart disease were examined prior to and 18.3 +/- 3 months after surgery, with 66% of the shunts proving to be patent. All patients were divided into 3 groups: group I--14 (47%) patients with patent shunts, group II--10 (33%) patients with partially patent shunts and group III--6 (20%) patients with occluded shunts. The group I and II patients displayed an improvement in the segmentary contractility and the integral function of the left ventricle as compared to the preoperative values. The group III patients showed a negative time-course of the segmentary and integral function of the left ventricle. In all cases of the impaired patency of the aortocoronary shunts there was progression of the atherosclerotic process in the basin of the shunted artery.

Seventy-five patients (aged 17-53) with an isolated lesion to the aortal valve have been examined. The study of correlations between clinico-instrumental and angiocardiographic findings has shown that the isotonic overload of the left ventricle as against the isometric one causes more pronounced changes in the contractility of the left ventricular myocardium which are expressed in an increased heart volume, the development of electrocardiographic manifestations of the left ventricular overload, a considerable enhancement in the myocardium weight and in the residual and end diastolic volumes of the left ventricle. The value of the gradient of the systolic pressure in patients with isolated aortal ostium stenosis determines the intensity of myocardial alterations. In patients with aortal valve insufficiency, the value of the pulse pressure is directly correlated with the myocardial state. The contractile function of the left ventricular myocardium in patients with combined cardiac aortal disease is dependent on the predominance of isotonic or isometric overloads of the left ventricle.

Twenty-four patients with postinfarction aneurysms of the heart and 9 patients with chest pains were investigated in order to assess the value of left-ventricular reserve parameters, proposed by the authors, i. e. the ratio between the percentage of change in ejection time and diastolic elasticity in the course of isometric stress and the increment at arterial blood pressure test. These parameters are shown to be more valuable for the assessment of left-ventricular function, as compared to conventional ventriculographic and intraventricular pressure parameters, measured at rest. The changes in ejection fraction and diastolic elasticity at isometric stress are a fairly reliable signal that the resection of heart aneurysm may be contraindicated.

The effect of selective coronary angiography on the amount of the coronary blood flow is discussed. The effect of sublingual nitroglycerin administration on the level of the coronary flow was also studied. The coronary flow was measured with the aid of intracoronary injection of Xe133 prior to selective coronary angiography, and on the 3rd, 6th and 10th minutes following the termination of the radiocontrast examination. The coronary blood flow was shown either to remain unchanged, or to decrease slightly on the 3rd minute after the termination of angiography, as compared with the value of this parameter prior to the examination. On the 6th minute some increase of the coronary flow is observed, on the average 12%, which subsequently returns to the initial level. Sublingual intake of nitroglycerin results in an increase of the coronary flow, both prior to and following coronary angiography.

In feline experiments and 65 clinical cases of ischaemic heart disease the efficacy of a new beta-stimulating agetn -- Ildamen -- was studied, the obtained effect was compared to that of Euphillin. Ildamen was found to be highly effective in patients with a moderately decreased coronary reserve and without atherosclerotic lesions in the coronary vessels.

The clinical course of the ischaemic heart disease was studied and compared with the ECG indices at rest, and under exercises, and with the data of selective coronary angiography in 189 patients. Three stages of decompensation of the coronary reserve were revealed. The efficiency of drug therapy and the indications for surgical management were studied with reference to the state of the coronary reserve.

Thirty patients with coronary heart disease were examined before and then 1.5 +/- 0.2 months after the operation of aortocoronary shunting. A total of 68% of the shunts proved patent. All patients were divided into 3 groups: group 1-14 (47%) patients with patent shunts, group 3-12 (40%) patients with partially patent shunts, group 3-4 (12%) patients with occluded shunts. The patients of the first two groups showed no changes in either the segmentary contractility of the left ventricular wall or in the time-course of the ejection fraction and left ventricular volumes. The patients of group 3 demonstrated the deterioration of both hemodynamic indices and parameters characterizing the segmentary contractility of the left ventricular wall which was caused by thrombosis of the aortocoronary shunt resulting in the development of ischemia or myocardial infarction in the zone of the shunted coronary artery.

Late results of surgery for chronic postinfarction aneurysm of the heart were reviewed in 48 patients. Comprehensive clinical and instrumental investigation demonstrated that aneurysm resection alone or in combination with aorto-coronary shunting or ventricular septoplasty resulted in clinical improvement in 60.4% of patients. However, surgery had basically no positive effect on left-ventricular myocardial contractility and pulmonary hemodynamics. The lack of positive changes in myocardial contractility is due to marked asynergy (akinesia) developing around the post-operative scar. The late postoperative outcome depends on both the type (akinetic or dyskinetic) of heart aneurysm, and timely referral for surgical treatment.

First experience with roentgeno-endovascular dilatation of a coronary artery is described, and reported data are reviewed. Roentgeno-endovascular dilatation is indicated for patients with a single 10-12-mm-long coronary arterial stenosis of hemodynamic significance, localized proximally in the left coronary arterial network, or along the trunk of the right coronary artery, where left ventricular function remains intact and the history of the disease is rather short (not more than 1.5 years). Contraindications for roentgeno-endovascular dilatation currently include local coronary arterial stenosis localized at a major branching-off junction; coronary arterial stenosis of more than 15 mm in length; multiple coronary arterial stenoses; stenosis affecting several major arteries; calcification of coronary arterial wall; left ventricular scarry changes in myocardial area of expected revascularization; absence of indications for aorto-coronary shunting.

The authors studied the effect of isoket on the central hemodynamics and myocardial contractility as well as on the conditions of myocardial functioning in 38 patients aged 28-53 years and suffering from coronary heart disease. The infusion of 2 mg of isoket at a rate of 400 micrograms/min was followed by a decrease in the arterial pressure with the maximum drop seen on the seventh minute (by 26% from the baseline value), a reduction in the end-diastolic pressure by 50%, and a lengthening of the preejection period without any significant changes in either the cardiac output or the total peripheral resistance. Taken as a whole these changes justify the conclusion that the influence of dinitrate isosorbite (isoket) on the central hemodynamics is largely due to its venodilating action leading to a reduction of the pre-load which in turn improves myocardial functioning.

Forty-six patients aged 39 to 59 years with coronary heart disease were examined. The control group comprised 10 healthy men. The myocardial injury was evaluated according to the ECG data. All the patients were subjected to selective coronarography and left roentgenokinoventriculography. To appraise the left ventricle myocardial contractility, the following indicators were made use of: the end diastolic pressure, ejection and the ratio of the peak systolic pressure in the left ventricle to the end systolic volume relative to the body surface. During kinoventriculography, left ventricle asynergy was detected in 65.2% of cases, whereas the reduction in the magnitudes of ejection and in the Ppeak/ESV X m2 index in 60.9 and 54.3% of cases, respectively. The false-negative result was 17.4% for ejection and 6.5% for the Ppeak/ESO m2 X index. Ejection and the Ppeak/ESV X m2 index were found to be highly informative. However in cases with a relatively preserved function of the left ventricle, it is necessary to take into account the magnitude of the Ppeak/ESV m2 X index which may attest to the pathological alterations in the myocardium in 62% of cases.

Subsequent to an examination of 133 patients, made several years after transmural myocardial infarction sustained by them, features specific for the clinical course of post-infarction cardiac insufficiency are analyzed. The examination included studies of the hemodynamics, veloergometry, measurements of the end diastolic pressure in the left ventricle, ventriculography and selective coronaroangiography. A considerable proportion of patients with extensive infarction in their history were found to suffer from chronic left ventricle incompetence with recurrent attacks of cardiac asthma. In the development of congestive cardiac insufficiency along the larger circulation an important role plays a sharply diminished contractility of the left ventricle due to the presence of extensive areas of akinesia and, in individual cases, also because of mitralism of the heart.

The effects of glycerol trinitrate (GTN), sodium nitroprusside and isoket on central hemodynamics, myocardial contractility and myocardial function have been compared. 65 patients with ischemic heart disease have been examined. All the patients were divided into 3 groups depending on the drug studied. GTN was administered sublingually at a dose of 0.5 mg, while sodium nitroprusside and isoket were infused at doses of 1.5 micrograms (kg min) and 400 micrograms/min, respectively. It has been shown that GTN and isoket effects on central hemodynamics were mainly mediated by their venodilating action and preload reduction, thus promoting to the improvement of the myocardial function. Hemodynamic effects of sodium nitroprusside on the cardiovascular system are mediated by its dilating action on the arterial bed and afterload reduction.