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The value of transaortal subvalvular myectomy after Morrow remains unclarified. We therefore analysed our results with HOCM with particular attention to the operation risk and the longterm results. 56 patients were treated at the Leipzig Heart Centre between January 1984 and August 1990 using the transaortic myectomy. In 16 patients an additional mitral valve replacement or -reconstruction was required. In 14 patients, other combined operations (aortic valve replacement, aortocoronary bypass) were indicated. In the postoperative observation period (up to 7 years; 141 patient-years; mean follow-up 4.2 yrs) detailed information was obtained at regular intervals about subjective complaints, ECG changes, left ventricular functional parameters and the weight of the heart muscle mass were recorded. The myectomy resulted in an alteration of the NYHA-class from 3.1 to 1.3 postoperatively (p < 0.05). The ventriculo-aortal pressure gradient reduced in the group myectomy (group I) from 69.2 +/- 5.2 to 23.3 +/- 2.7 mmHg postoperatively. In the myectomy+mitral valve repair group (group II) the intracavitary pressure gradient was even reduced to 11.7 +/- 2.2 Torr (p < 0.05). The Sokolov-Lyon-Index was 3.7 +/- 0.19 mV preoperatively and went down to 2.9 +/- 0.16 mV. The heart muscle mass decreased from 680 g to a postoperative value of 430 g (p < 0.05). The relation of BAR and calcium channel density of 0.5 +/- 0.1 in HOCM versus 0.9 +/- 0.08 in a control group (n = 6) proves the increased number of calcium channels in HOCM.

Unlabelled: Between 1/84 and 6/91 56 patients were treated for hypertrophic obstructive cardiomyopathy (HOCM): the Morrow technique alone was performed on 40 patients (group 1), in 16 patients (group 2) an additional replacement (n = 13) or reconstruction (n = 3) of the mitral valve was indicated. In a total of 14 cases coronary artery bypass grafting and aortic valve replacement was performed in addition. Postoperatively (mean follow-up 4.2 yrs, 141 patient-years) left-ventricular diastolic and systolic function parameters, heart muscle mass, ECG findings, and symptomatology were recorded and the ratios of beta-adrenoreceptor density to density of the calcium channel were measured., Results: Pressure gradient decreased from 69.2 +/- 5.2 (group 1) and 75.1 +/- 4.8 (group 2) to 23.3 +/- 2.7 and 11.7 +/- 2.2 mmHg postoperatively. Likewise Sokolow-Lyon index decreased from 3.5 +/- 0.2/3.7 +/- 0.2 to 2.9 +/- 0.2/2.8 +/- 0.3. The quotient time-to-peak-velocity/left-ventricular-ejection-time decreased significantly in group 2 from 58.6 +/- 6.3 to 41.9 +/- 5.8 (p less than 0.05). The heart muscle mass, determined echocardiographically, decreased from 680g to 430g (p less than 0.05). Isovolumetric tension time, isovolumetric relaxation time, and E/A ratio at rest and after stress showed typical characteristics. Ca(++)-channel density was clearly raised in all patients, with no differences between the two groups being observable. We conclude from our results: The most marked improvements in clinical and left-ventricular functional parameters were experienced by patients in group 2 (myectomy+MVR).(ABSTRACT TRUNCATED AT 250 WORDS)

In a five-year retrospective study we investigated the wound infection rate after median sternotomy in 2805 adult patients on whom elective surgery had been performed with extracorporeal circulation. On the basis of 14,700 apparently relevant data from 101 patients with wound healing disturbances at the sternotomy site, both the significance of predisposing risk profiles and the prevalence of nosocomial pathogens were evaluated. The control group was formed by 100 patients selected at random. The results were checked for statistical significance using the X2 test for alternative characters; the significance level was set at alpha = 5%. The infection rate observed in our group was 3.6%, which was assigned to 5 internally defined degrees of severity. Cases of healing by second intention were caused to 93% by coagulase-negative staphylococci and staphylococcus aureus. Factors leading to a decrease in oxygenation of the wound area (low-output syndrome, rethoracotomy), diabetes, obesity and the duration of wound drainage were accompanied by a significantly more frequent occurrence of wound healing disturbances. On the other hand, perfusion-technical parameters, operation duration, revascularisation techniques (IMA/ACVB), pulmonary conditioned hypoxemias and the end-of-year desinfection usual in our clinic had no influence on wound healing. Seasonal fluctuation of the epidermal microclimate appear to be responsible for the prevalence and virulence of the pathogen strains in the clinic environment. The preventive measures used in cardiosurgical clinics do not yet represent a fully developed prophylaxis against exposure to nosocomial pathogens.

It is reported on first own experiences in the cardiosurgical treatment of patients with terminal renal insufficiency. Frequency of cardiovascular complications and their high lethality in this group of disease force into early and routine use of cardiological diagnostics and cardiosurgical therapy. The surgical indication should exclusively be based on the severity of the present heart disease. The permanent dialysis treatment is no contraindication. When the patients are carefully selected and with close cooperation of all specialties participating the operative risk of patients with terminal renal insufficiency does not essentially differ from that one of patients with healthy kidneys.

The aim of the present study was to check the value of cw-Doppler echocardiography for the assessment of severity of congenital aortic and pulmonary stenoses in children and adolescents. Over a period of 3 years 217 children and adolescents with aortic and 98 with pulmonary stenosis, resp., underwent echocardiography. In 21 patients with aortic and in 23 with pulmonary stenosis pressure gradients were determined by cw-Doppler as well as intracardiac pressure measurement. The comparison showed excellent accordance between both sorts of data for aortic stenoses (r = 0.939) and pulmonary stenosis (r = 0.969). These results show that Doppler echocardiography is a reliable diagnostic method for the determination of pressure gradients. Thus, it allows correct selection of children and adolescents with aortic stenosis for surgery. So far, 12 patients have been operated on without preoperative cardiac catheterization. Indication for balloon valvuloplasty in patients with valvular pulmonary stenosis can be based safely on 2 D- and Doppler echocardiography.

Nowadays, by means of the conventional and Doppler echocardiography it is possible to diagnose with high sensitivity and specificity a defect of the aortic valve. Apart from references to the etiology kind and size of the lesion of the aortic valve, the degree of an obstruction and/or regurgitation as well as degree of hypertrophy and function of the left ventricle are reliably recognizable. Thereby the one- and two-dimensional echocardiography on the one hand and the Doppler methods on the other a different value is ascribed to in the diagnostic statement. By means of Doppler echocardiography the essential functional parameters of a stenosis of the aortic stenosis such as pressure gradient and surface of the opening of the aortic valve are to be determined noninvasively. An insufficiency of the aortic valve only by Doppler methods can be determined non-invasively without doubt. Under certain prerequisites the complex echocardiography can be made dispensable the invasive diagnostics in patients with defects of the aortic valve under preoperative aspects--apart from a coronary angiography.

Despite the small cohort of patients with HOCM could be shown that the routine application of the conventional and colour Doppler echocardiography after myectomy is indicated and reasonable. The modern echocardiography is able to assess with high individual reliability the therapeutic aim of myectomy--drastic reduction of the intracavitary pressure gradient. Significant changes were also the results in the systolic acceleration time (TPVS/LVET standardized on the LVET and the diastolic measuring parameters VmaxE, ATE and TVIE/TVIA), the importance of which is partly still fully open.

Before operation as well as over a mean postoperative period of 8.9 years 222 adults with atrial septal defects underwent a follow-up examination concerning frequency and clinical significance of supraventricular dysrhythmias. Thereby disturbances of the formation of stimuli were found before the operative procedure in 60 patients and after the correction in 115 patients. Disturbances of the sinoatrial and atrioventricular conduction were registered preoperatively in 53 cases and postoperatively in 81 cases. Within these statistically significant increases in particular the significant forms of dysrhythmia elevated after the atrial septal defect closure. Thus the tachycardiac atrial dysrhythmias increased from 7 to 28%, complex arrhythmias even from 2 to 16%. Of dysrhythmias to be taken seriously patients with IAVC and supraventricular defect are significantly more frequently affected than those with interatrial septal defects. Size of the defect, shunt volume and pressure of the pulmonary artery did not show any connections with the frequency of dysrhythmia. On the other hand, when accompanying cardiac anomalies, symptoms of a manifest heart insufficiency were present and at an operation age over 40 years arrhythmias were proved more frequently. The complaints of the patients did not correlate with the endangering, but are imprinted by the haemodynamics and its postoperative normalization. By the established profile of complaints and a decrease of frequency from 76% pre- to only 40% postoperative the patient with atrial septal defect cannot estimate his individual risk and needs an adapted long-term concept for his cardiological care.

The urgent coronary surgery performed in patients with high risk unstable angina (rest pain greater than 48 h) shows still different results. We found in 57 urgent operated patients the same functional and clinical results as after elective bypass grafting. A higher in hospital mortality after urgent coronary surgery based on a higher number of grafts are occluded in the early postoperative period. The better prognosis concluded that the use of urgent coronary surgery is the therapy of choice in patients with refractory unstable angina pectoris.

Reported in this paper are 17 abdominal complications among 2,161 patients, following cardiac surgery, using cardiopulmonary bypass. This incidence is comparatively low, accounting for only 0.78 percent, whereas figures between 0.3 and 1.6 percent have been reported in the international literature. Lethality worldwide has been quoted to be between 25 and 50 percent and amounted to 23.5 percent for the above patients. This seems to underscore the great importance of early decision-making on appropriate therapy. Haemorrhage from the upper gastro-intestinal tract due to stress-related ulcers had been the predominant finding in this study. Acute pancreatitis developed in two patient, one of them ending in death. Acute cholecystitis and ischaemic colonic gangrene were additional complications. No significant extension of perfusion periods was established, which was in deviation from findings made by other authors.

All over the world the therapy of acute myocardial infarction has concentrated upon saving the ischaemically injured, but still viable cells of the myocardium. Also the acute coronary surgery, which among our groups of coronary-surgical patients has a proportion of 3.5% with 41 patients, answers this purpose. The preferred indication groups for acute coronary-surgical operations are the occlusion of the vessel after coronary dilation and the condition after intracoronary fibrinolysis. In these 22 patients the hospital lethality was only 4.5%. The reasonable active approach in acute myocardial infarction, particularly the combination fibrinolysis - acute coronary surgery, is a hopeful enlargement of the previous therapy for the highly imperilled patients with myocardial infarction.

The influence of PGI2 and iloprost on the contents of high energy phosphates, cAMP, glycolytic metabolites and on cardiac performance was investigated in open-chest dogs subjected to 3 h of ischaemia, induced by occlusion of the left anterior descending coronary artery. The administration of drugs for 2 h, starting 1 h after the onset of ischaemia, resulted in a normalization and an appreciable reduction in the loss of high energy phosphates in the non-ischaemic and ischaemic left ventricular muscle, respectively, leading to an improvement in the phosphate potential of the cardiac tissue. A reduction in the ischemia-induced rise in cAMP levels was observed, indicating a lower catecholamine overflow in the presence of these drugs. PGI2 and iloprost in the dose employed significantly decreased cardiac preload, which was found to be elevated in the untreated animals after coronary artery ligation. The observed effect of PGI2 and its mimetic on the haemodynamics, as well as on myocardial cAMP and high energy phosphate levels of the heart, may be considered helpful in the phase of temporary imbalance between energy demand and supply during acute ischaemia.

Enzyme-histochemical changes due to temporary ischemia of canin heart muscle with subsequent reperfusion of the ischemic damaged muscle are described. In relation to findings in the rat, the first enzyme-histochemical changes were observed after two hours of coronary artery ligation. These changes were more impressive after 4 hours of ligation. A further increase was caused by the reperfusion.

The growing incidence and importance of cardiovascular diseases in a number of countries calls for systematic quest for most efficient methods of treatment, which besides prevention and drug therapy include also surgical treatment. A group of experts from member countries of the Council for Mutual Economic Assistance (CMEA) has worked out a scientific prognosis of trends of the development of cardiovascular surgery, which include surgical treatment of ischaemic heart disease, congenital and acquired heart defects, renovascular hypertension and affection of the aortic arch. The prognosis includes also an estimate of the number of operations which will have to be performed in the mentioned diseases per 1 million inhabitants of the CMEA member countries.

In 25 (5.3%) of surgically treated coronary patients the mammarocoronary anastomosis was performed. A follow-up angiographic checkings made after 1 to 3.5 years proved its patency in all instances. The minimal lumen of the internal thoracic artery at the anastomosis site should be 1.5 mm. The use of the internal thoracic artery, with the appropriate indication, is limited to the anterior ventricular branches of the left coronary artery. The peculiarities of the operation are described.

Macroscopic and microscopic studies on the anterior interventricular ramus of left coronary artery, internal thoracic artery, and great saphenous vein were carried out 50 dead, aged 21 to 60 years. The internal thoracic artery was always normal whereas in 40 cases stenosing coronary sclerosis was found. At mammography, 25 patients with operable coronary obstruction also showed no degenerative alterations of this systematic artery. With a diameter of 1.5 mm in the 5th intercostal space the internal thoracic artery was fit for performing an anastomosis.

384 patients with ischaemic heart disease were treated surgically. Out of 165 patients operated upon consecutively, in 38 (23%) an intramural course of coronary arteries was found. Peroperative diagnosis of the intramural course of the anterior interventricular branch is feasible with a high probability; diagnostic criteria were also elaborated for the intramural course of the marginal branch. Several aspects of the operation technique and tactics are discussed.

The influence of glucose-insulin-potassium infusion in combination with a mechanical assist device (intraaortic balloon pumping, IABP) on the levels of high energy phosphates in the canine heart after coronary artery ligation was compared with the effect of a separate application of these measures to protect the acute ischaemic myocardium. The combined method normalized the tissue content of creatine phosphate in the nonischaemic tissue contrary to the application of the mechanical or pharmacological assistance alone. In the ischaemic cardiac tissue only the combination of both methods reduced the loss of creatine phosphate, ATP and the sum of adenine nucleotides. With the balloon pumping a reduction in lactate accumulation was achieved, which, however, was significantly lower than that obtained by the combination of heart protective measures: IABP plus glucose-insulin-potassium.

A two-hour acute ischaemia of the myocardium was induced in dogs by ligature of the coronary arteries and the effect produced on the qualitative and quantitative ultrastructure of heart muscle cells by infusing "hylase", a hyaluronidase preparation, was examined. The changes in both the central and peripheral ischaemic zones following hylase infusion are more severe than after ischaemia alone. Particularly the mitochondria showed an increased dissolution of the outer membrane. In the case of ischaemia the percentage of mitochondria in the peripheral zone is 29.6%, in the central zone 27.6%; after hylase infusion it is 25.9% in the peripheral zone and 32.3% in the central zone. After hylase infusion, the percentage of sarcoplasm in the central zone rises to 120.7% and to 186.8% in the peripheral zone. In view of the fact that macroscopic, histological and histochemical findings also show negative effects, the infusion of hyaluronidase is not recommended.

The influence of prostacyclin (PGI2) alone or in combination with intraaortic balloon pumping (IABP) on the levels of energy-rich phosphate compounds was investigated before and after coronary artery ligation in canine myocardium. There was a higher level in creatine phosphate in the ischemic as well as non-ischemic areas of the myocardium after treatment with PGI2, however the most protective effect was registered after a combination of PGI2 and IABP. PGI2 also reduces the release of cathepsin D activity into the blood independently whether or not a mechanical support of the heart after coronary artery ligation was performed.

In the last three years, of a total of 617 patients undergoing surgery for ischemic heart disease, 53 were women (8.6%). With one exception, all were in or shortly before the menopause. As compared with men, the women were found to have a preponderance of risk factors. The most unfavorable combination, that of hypertension and hypercholesterolemia, was present in one-third of the patients. Hospital mortality for isolated revascularization was higher in women at 4.9% than in men at 1.5%. The one-year survival rates, however, of 94.4% and 95%, respectively, did not differ between the two sexes. In women, the number of grafts per patient was 2.1 as compared with 2.9 in men. Complete revascularization was achieved less frequently in women than in men; similarly graft patency rate at one year of 66% in women was less than the 84% observed in men. The more marked coronary sclerosis as well as morphologic characteristics of coronary arteries in women construe a special challenge to the surgeon and prerequisite a high degree of technical skill.

Myocardial ischaemia in the dog lasting for three hours is followed by swellings of the mitochondria and dilatation of the sarcoplasmic reticulum. The volume density (Vv) of mitochondria in the peripheral ischaemia zone is 0.2890, that of sarcoplasmic reticulum is 0.0101. Prostacyclin was administered either i.v. or by triggering in conjunction with an intra-aortic balloon pump which led to an increase in the volume density of the mitochondria, mainly as a result of an increase in the volume of average mitochondria. The dilatation of the sarcoplasmic reticulum is reversed. It was not possible to prove in our investigations that prostacyclin provides protection against myocardial ischaemia.

The influence of verapamil (V) and of V combined with glucose-insulin-potassium (VG) on ischemic injured myocardium was investigated in dogs after ligation of the left anterior descending coronary artery. Three hours after coronary artery ligation with VG application during the last two hours the left ventricular end diastolic pressure (LVEDP) and the pressure rate product were decreased in contrast to the behaviour after V infusion. Contents of ATP and creatine phosphate were preserved in equal extent by V and VG, but the lowest content in inorganic phosphate was found in ischemic and nonischemic left ventricular tissue after VG application. Thus, VG seems to enable the tissue to save more effective energy rich phosphates and to contribute to the economization of cardiac work by reduction of preload.

Aspects of indication, of the surgical technique as well as long-term results are discussed on the basis of own experiences in 279 coronary artery operations. Patients suffering from unstable angina pectoris should be operated on as soon as possible. In cases with stable angina pectoris due to a triple vessel disease the long-term results are better with surgery than without.

Cardiac tamponade occurred in 9 (1,8%) of 488 patients following open-heart surgery. Delayed cardiac tamponade was observed in one case (0,2%). The mediastinal tamponade was caused by early occlusion of the chest tubes, pericardium closure and administration of anticoagulants. A reliable sign of mediastinal tamponade is the expanding cardiac silhouette demonstrated by roentgenogram. In outpatients receiving anticoagulants following open-heart procedures a life-threatening delayed cardiac tamponade may develop.

In comparative studies in 36 mongrel dogs it was tried to find out how far intraaortic balloon pumping (IABP) applied solely and in combination with glucose-insulin-potassium (GIK) might influence the degree of acute myocardial ischemia. The ischemia lasted 3 hours. After 60 min myocardial ischemia IABP, the isolated GIK infusion, or the combination of IABP plus GIK were used. The directed GIK application into the aortic root was carried out by electronic triggering during the diastolic augmentation via a precoronary catheter. In the ischemic and in the non-ischemic myocardium of the left ventricle, ATP, creatine phosphate, and lactate were determined. Electronmicroscopical studies were carried out qualitatively as well as quantitatively. The isolated use of IABP suggested no protection of the energy-rich phosphates. The most significant morphological changes were found when exclusively the coronary ligature was applied and when only IABP was used, respectively. The best protective effect was achieved by our technique of the triggered GIK infusion via the precoronary catheter in combination with IABP. The ATP value (n mol/mg w.w.) in the ischemic area was 3.06 and in the non-ischemic one 4.96 in comparison to 1.96 and 3.99, respectively, in the control group. The creatine phosphate (n mol/mg w.w.) was 4.18 in the ischemic and 9.38 in the non-ischemic area in contrast to 2.36 and 6.99, respectively, in the control group. The technique of the triggered drug supply in combination with IABP offers the following advantages: --additive summation of IABP and substrate supply directed to the myocardium --high drug concentration in the myocardium --smaller drug load of the whole organism --clinical use of instable substances.

For the detection of atropine effects the hemodynamic changes of 50 patients with coronary heart disease being premedicated intramuscularly with pethidine/diazepam have been registered 3 and 6 minutes after intravenous atropine application (0.01 mg/kg). All patients showed an increase of the heart rate, but only 80% demonstrated an increase of cardiac index at the same time. 20% of these patients exhibited a decrease of the stroke volume, whereas in 5 cases out of this group the patients complained ischemic pain. In a second part of this investigation the results of an induction of neuroleptanalgesia have been compared with another group of 50 patients with the same disease. The function of the right and left ventricle was significantly depressed in the patients with atropine application before the induction of anaesthesia. The results are discussed as an important argument against the routine use of atropine for premedication purposes.

The influence of PGE1, iloprost and a combination of both on high energy phosphate levels in isolated rat hearts reperfused 1 h following 20 min of global ischemia was investigated employing 31P-NMR-spectroscopy. Whereas PGE1 induced a slight reduction in the decline of the creatine phosphate/inorganic phosphate. ATP/inorganic phosphate ratio and NMR-energetic index during ischemia, iloprost application was followed predominantly by a temporary but marked improvement of the creatine phosphate/inorganic phosphate ratio during the early period of reperfusion. The best results in preservation of high energy phosphates were achieved after simultaneous application of PGE1 and iloprost. It is presumed that the accelerated normalization of the heart function observed immediately after ischemia in the eicosanoid treated hearts is related to the more rapid recovery of intracardial high energy phosphate level.

Following coronary artery ligation (CAL), levels of cAMP and the activity ratio of cAMP-dependent protein kinase, of phosphorylase kinase, and of phosphorylase are significantly elevated in both ischemic and nonischemic areas of the canine left ventricle. The aerobic level of cAMP was found to be 0.4 to 0.6 pmol/mg myocardium only after a precooled clamp or a cryobiopsy device was employed to guarantee tissue freezing in situ. Maximal changes in response to ischemia are observed within 2 min in both parts of the heart. Twenty minutes after the onset of ischemia, different responses have been found in the nonischemic and ischemic tissue. Whereas the levels of cAMP and the activity ratio of protein kinase, of phosphorylase kinase, and of phosphorylase returned to aerobic values in the nonischemic area, these parameters remained elevated in the ischemic area. The changes in the levels of myocardial cAMP and in the cAMP-dependent protein kinase activity ratio following CAL could be prevented by propranolol.

Congenital corrected transposition of the great arteries in which there is both an atrio-ventricular and a ventriculo-arterial discordance has surgical significance only in consequence of the associated cardiac anomalies. Their surgical correction is subject to multifarious problems. An exceedingly rare cause of a left-ventricular outflow tract obstruction erroneously interpreted preoperatively in an eight-year-old boy is reported. In an l-transposition with inversion of both ventricles, the diagnosis "valvular pulmonary stenosis" was made preoperatively. However, a normally arranged tricuspid pulmonary valve without stenosis was revealed intraoperatively. On the other hand, dystopic valvular tissue in the form of a monocuspid atrioventricular valve which was attached to an accessory papillary muscle with several tiny tendons was found below the pulmonary valve in the morphological left ventricle. The accessory valve cusp, which was the cause of the hemodynamically relevant subvalvular pulmonary stenosis, had no connection with the mitral valve. The abnormal valve cusp was resected without injuring the normal structures. The angiographic follow-up after one year no longer revealed any pressure gradient. This case report points out the possibility of an outflow tract obstruction caused by a complete accesory valve cusp.

Anaesthetized mongrel dogs were subjected to occlusion of a coronary artery. The resulting myocardial infarction was observed for three hours. One hour after occlusion, infusion of the stable prostacyclin analogue iloprost or saline was started. In the control group myocardial infarction was associated with an increase of the ratio TXB2/6-keto-PGF1a which was abolished by iloprost treatment. After occlusion in the control group, the atherosclerosis index (TC-HDLC): HDLC was increased, but in the iloprost-treated group it was significantly decreased. The results of this study suggest that the administration of iloprost is able to prevent changes in eicosanoid metabolism and lipoprotein pattern after coronary artery occlusion in dogs.

1. In 12 dogs the right part of the diaphragm was stimulated 4, 5, 8, 11, and 14 weeks by means of a pacemaker. 2. Essential findings have been the increase of the amount of glycogen after 5 weeks, the increase of myofilaments per myofibril after 8 weeks, and the increase in the share of mitochondria in the 11th week. After 14 weeks all values have reached again their initial level as the result of an adaptation. 3. From the quantitative structural findings it can be taken that the diaphragm musculature is not changed by the electrostimulation in such a way that the functional preconditions for covering heart muscle deficiencies by diaphragm flaps are given.

A total ischaemia of one area of the myocardium was produced by ligature of a coronary artery in dogs. After 30 min, 1 hr, 2 hrs, and 4 hrs the ligature was loosened and the artery was for 1--2 hrs reperfused up to 4--7 days. At the end of the ischaemia and after reperfusion the ultrastructure of the myocardium was qualitatively and morphometrically investigated. The findings concerned: loss of glycogen (partly glycogen accumulation), mitochondrial swellings and fusions and development of megamitochondria, loss of cristae, rupture of the mitochondrial outer membranes, relaxation or supercontraction of the myofibrils, vesicular and vacuolar changes of the sarcoplasmic reticulum, oedema of the sarcoplasm, rupture of the sarcolemma. No significant differences of the quantitative parameters could be observed during the ischaemia from 30 min to 4 hrs: myofibrils 53.65--59.74%, mitochondria 26.51--33.59%, sarcoplasm 8.22--11.86%, sarcoplasmic reticulum 1.41--2.63%, lipofuscin 0.05--0.87%, lipids 0.01--0.10%. In comparing the data of the single animals we could determine significant differences between some parameters at the ends of the ischaemic phase and of the reperfusion phase, but as far as the findings are concerned both increases and decreases could be observed. The investigations show that the limit of the reversibility of damages in myocardial cells is about 45 min; in special cases a longer survival time may be taken into account. Reperfusion has different, though not always positive, effects.

In a complex experimental study on 52 dogs the myocardium was examined after ischemia and reperfusion of various duration. Morphologic, metabolic, and functional findings proved that a short-term reperfusion after coronary occlusion for more than 2 hours has disadvantageous effects on the regression of ischemic lesions. During the early period (up to 3 days) this is caused by the "no-reflow" phenomenon. Combined qualitative and quantitative findings are required for correct appraisal of the ultrastructural alterations after reperfusion. In acute coronary occlusion, early revascularization after passing the crucial initial phase is advantageous, because the extent of myocardia necrosis is decreased by the prolonged reperfusion, thus leaving a larger myocardiac reserve in case of re-infarction. Clinical conclusions are drawn.

An animal experimental study was carried out in order to compare the therapeutical value of two different surgical methods for excising the subcutaneous implanted Lewis lung carcinoma - tumor excision with scalpel or with carbon dioxide laser. The radicalism of operation methods, the survival time, and the tumor local recurrences were performed. The therapeutic effectivity of tumor excision with the carbon dioxide laser is more favourable than the scalpel method.

The authors examined the effects of reperfusion after temporary ischemia in 50 dogs. The morphologic alterations were documented by methods of electron microscopy, fluorescence microscopy, and histochemistry. Lactate and activity of glycogen phosphorylase were assessed. According to the results, the optimal ischemia interval is 30 to 60 minutes for rational application of reperfusion, while it is just possible after 120 minutes. After a 4-hours-period of ischemia reperfusion increase morphologic damage of myocardium and impairment of myocardial metabolism. Prolonged reperfusion of 7 days resulted in a reduced extent of infarction compared with controls. In non-ischemic myocardium the morphologic and metabolic alterations were less expressed. The effects of "no-reflow"-phenomenon and conclusions for clinical practice are discussed.

The effect of drugs on eicosanoid production and on the development of atherogenic index was investigated in canine myocardial ischemia. Iloprost, verapamil, the trapidil derivative AR 12463 or 0.9% NaCl solution were administered 60 min after coronary artery ligation in anaesthetized dogs. Both iloprost and AR 12463 reduced the thromboxane A2/prostacyclin (TXA2/PGI2) ratio in coronary sinus plasma in comparison to controls. The atherogenic index was significantly decreased in the iloprost as well as in the AR 12463-treated group in comparison to the control group. Verapamil had no influence on the investigated parameters.