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A centuries long history of mining and mineral processing has resulted in elevated Cd, Pb and Zn soil concentrations in the vicinity of the Silvermines abandoned mine site (AMS), Co. Tipperary, Ireland. A process for preliminary evaluation of environmental risk was developed and implemented. Potential pathways of metal compound transport and deposition were mapped and used to optimise the subsequent site investigation. Elevated soil metals are shown to be predominantly in areas where metal deposition in soil is associated with water related pathways (surface runoff, seasonal groundwater seepage and floodplains). Extensive areas of soil in the surrounding district are classified as contaminated on the basis of Cd, Pb and Zn concentrations, both total and potential bioavailable (EDTA-extractable). The most affected areas, with metal concentrations in soil comparable with that within the AMS, were floodplains located 2–3 km downstream from the site. Assessment of the sequential effects on grass and grazing animals indicates that Pb poses the greatest risk due to its high toxicity and high concentrations in soil (more than 10 000 mg kg−1). Within floodplain areas grazing cattle may intake a lethal dose of Pb. On the basis of the investigation an approach to risk assessment was developed which allowed quantified assessment of the risks related to individual metals, areas of contamination and contamination targets.

This paper describes a holistic methodology for the investigation of environmental contamination from abandoned mine sites (AMSs), and is based on a case study of the Silvermines AMS. Groundwater modelling, surface water temperature monitoring, and a geographical information system (GIS) were used to undertake a preliminary delimitation of areas where soil, fluvial sediments, and surface and groundwater were contaminated. Subsequent soil and water sampling and analysis confirmed the accuracy of these predictions. Significant contamination of environmental media in the vicinity of the AMS was largely the product of water-borne pollutants. The concentration of Pb was high in streams receiving direct discharge from the AMS, but decreased rapidly downstream. Concentrations in stream sediments showed the same pattern. Extremely high Pb concentrations were also observed in sediments downslope from the AMS where groundwater discharges into surface drainage. Soil Pb concentrations were highest on floodplains and in areas affected by surface runoff and seasonal groundwater seepage. The methodology described here allows effective and cost-efficient investigation of the environmental impact of AMSs, which in turn provides the basis for site rehabilitation.

A centuries long history of mining and mineral processing has resulted in elevated Cd, Pb and Zn soil concentrations in the vicinity of the Silvermines abandoned mine site (AMS), Co. Tipperary, Ireland. A process for preliminary evaluation of environmental risk was developed and implemented. Potential pathways of metal compound transport and deposition were mapped and used to optimise the subsequent site investigation. Elevated soil metals are shown to be predominantly in areas where metal deposition in soil is associated with water related pathways (surface runoff, seasonal groundwater seepage and floodplains). Extensive areas of soil in the surrounding district are classified as contaminated on the basis of Cd, Pb and Zn concentrations, both total and potential bioavailable (EDTA-extractable). The most affected areas, with metal concentrations in soil comparable with that within the AMS, were floodplains located 2-3 km downstream from the site. Assessment of the sequential effects on grass and grazing animals indicates that Pb poses the greatest risk due to its high toxicity and high concentrations in soil (more than 10,000 mg kg-1). Within floodplain areas grazing cattle may intake a lethal dose of Pb. On the basis of the investigation an approach to risk assessment was developed which allowed quantified assessment of the risks related to individual metals, areas of contamination and contamination targets.

Polycardiography was used to examine myocardial contractile parameters: preejection and ejection periods and contractility coefficient in 90 patients with coronary heart disease running without complications postoperatively following aortocoronary bypass and cardiac aneurysm resection. The magnitude and length of lower myocardial contractility were found to be associated with the baseline extent of coronary and cardiosclerosis, the signs of congestive heart failure, the value of ejection fraction, and intraoperative parameters such as the duration of extracorporeal circulation and myocardial ischemia, the number of shunts and their blood flow. Early drug correction of complications and a scientifically substantiated approach to the physical rehabilitation of those operated on may be applied with due account of the changes in myocardial contractility.

A 1.5% nonachlazin solution containing substances which promote its absorption from the gastrointestinal tract increases coronary blood flow in cats 2--3 minutes after its administration into the stomach. After single administration this solution arrests a developing attack of angina pectoris in patients, improves the findings of spiroergometry, and in regular (3 times daily) medication prevents attacks of angina pectoris or makes them occurs less frequently in the very first 24 hours. The solution is most effective in patients with a high or moderate coronary reserve and affection of one or, in a lesser degree, of two coronary arteries. The solution does not cause a drop in arterial pressure, headache or dizziness.

The observations cover 96 male patients, aged from 30 to 61 suffering ischemic heart disease with clearly manifested stenocardia. The diagnosis in all patients was made on the base of a thorough clinical examination, the results from the electrocardiography and the selective coronarography. The data obtained from the clinical instrumental and clinical-angiographic examinations reveal that a correlation exists between the stage of the coronary arteries lesions, the patients's age, number of previous myocardial infarctions, severity of stenocardia and the state of the coronary reserve. The extent growth of the coronary arteries lesion goes in parallel with the patients' age advancement, the number of previous myocardial infarctions, severity of stenocardia and the diminution of coronary reserve. In this respect the character of stenocardia and the state of coronary reserve have the highest informative value. Our examinations failed to establish any correlation between the stage of the coronary arteries lesion and the stage and eytension of myocardial lesion on the electrocardiogram as well as between the stage of coronary arteries lesion and the duration of the illness.

The indices of pulmonary ventilation and gas exchange, oxygen consumption per 1 kgm of work, the restoration coefficient, the effectiveness of work, etc. were studied at rest, during dosaged physical exertion on a bicycle ergoraph, and in the restoration period in 50 healthy individuals and in 175 patients with ischemic heart disease. Selective coronary angiography was conducted in all of the patients. Spiro-bicycle-ergometry is an informative method in the diagnosis of ischemic heart disease, enabling the physician to presume the presence of coronary sclerosis and judge the degree and extent of involvement of the coronary arteries before performing coronarography. With the gradual increase in the number of involved arteries, there were noted a gradual decrease of the restoration coefficient, diminution of the effectiveness of work, and an increase in oxygen consumption per 1 kgm of load. Changes in spiro-bicycle-ergometric indices in patients with ischemic heart disease and normal coronary arteries had the same trend as those in patients with coronary atherosclerosis.

Late results of left ventricular postinfarction aneurysm resection were studied in 112 patients. The results were good or satisfactory in 84.7% of patients, who mostly showed no hemodynamically significant coronary arterial stenoses or with one major branch affected, and a dyskinetic aneurysm. Clinical improvement was accompanied by a significant increase in stress tolerance, an increase in maximum oxygen utilization per 1 kg body weight, a decrease in the proportion of oxygen debt to oxygen want and better myocardial contractility, evidence of increased physical working capacity of the postoperative patients. The results were poor in patients with multiple coronary arterial stenoses and heart failure uncontrollable by medication.

Non-invasive diagnostic procedures (electrocardiography, spiroergometry, polycardiography) were compared with selective coronarography and left-side radioventriculography in 132 patients with chronic post-infarction aneurysm of the heart, in order to demonstrate their respective diagnostic values for the assessment of coronary and myocardial reserves of the heart. It was shown that physical stress tolerance, pO2max, the oxygen debt/oxygen requirement percentage ratio could be indicative of disturbed coronary reserve, while prolonged P wave and left-atrial deviation time, the number of abnormal Q and QS waves and increased resting myocardial contractility index (above 0.550) suggested impaired myocardial contractility.

Seventy-seven patients with chronic ischemic heart disease were treated in single-seater oxygen hyperbaric chambers; 52 patients had angina pectoris of effort or angina of effort and at rest while 25 patients with macrofocal postinfarction cardiosclerosis had insufficiency of pulmonary or systemic circulation. Treatment consisted of 12--15 procedures. The use of hyperbaric oxygenation in a complex with drug therapy makes it possible to alleviate or arrest the attack of angina pectoris and relieve considerably the symptoms of cardiac decompensation. The initial condition of central hemodynamics affects greatly the results of barotherapy. Normal parameters of hemodynamics hardly change after treatment. At the same time, in patients with markedly reduced myocardial contractility hyperbaric oxygenation causes evident positive changes in hemodynamics. The combination of hyperbaric oxygenation with drug therapy improves the effect of treatment significantly.

The results of examination of 25 patients (18 with ischemic heart disease and 7 with cardialgia of other etiology) are discussed. The arteriolo-capillary bed of the coronary arteries was studied by intraarterial injection of albumin aggregates labelled with radioactive isotopes. A correlation was revealed between the degree of microcirculatory disorders and the results of electrocardiography. With increase in the degree of microcirculatory disorders, cicatricial changes in the left ventricular myocardium were found more frequently and a history of myocardial infarction (in 11 persons) and the development of left ventricular aneurysm (in 2 patients) were noted. Certain indices of integral function (EF, VcF, MNSER) and regional contractility (% delta r, L) of the left ventricle were determined in 14 patients. Among these parameters characterizing left ventricular function (EF, VCF, MNSER, % delta r, L), VCF, MNSER, and % delta r, L are most sensitive. No correlation was revealed between the state of the myocardial microcirculation bed and EF, VCF, and MNSER, but a definite correlation was found between it and % delta r, L (in the form of regional hypo- and hyperkinesia and paradoxical pulsation). Normal coronary arteriograms do not exclude the presence of ischemic heart disease and other primary diseases of the myocardium. Patients of this category should be examined more scrupulously to detect disorders of blood supply to the myocardium and function of the left ventricle.

Sixty three patients were examined. The diagnosis of all was made on the base of clinical picture, electrocardiographic examinations and the results from the selective coronarography. The following indices of the oxygen consumption and gas metabolism were analysed in the paper: oxygen consumption per kilogram body weight, oxygen consumption per kilogramometer work performed, labour effectivity and restoration coefficient. The results obtained reveal that the adaptation ability of the respiratory and cardiovascular system in conditions of physical loading was disturbed in patients with chronic ischemic heart disease. At the same time, the physical capacity for work and the restoration coefficient were also disturbed. The decrease of oxygen consumption per kilogram body weight, deteriorated labour effectivity, restoration coefficient and the increased oxygen consumption per kilogramometer work performed occur in parallel with the extension of the lesions of the coronary arteries and the diminution of coronary reserve. The results from those examinations, together with the results from a series of non-invasive methods for the examination of cardio-vascular system could aid the thorough diagnostic-prognostic character of ischemic heart disease and give a tentative idea for the stage of the coronary arteries lesions prior to coronarography.

The remote results of aorticocoronary shunting were studied in 105 patients (follow-up periods of 1 to 5 years and more). The values of bicycle ergometry and spiroergometry (rehabilitation coefficient, oxygen expenditure per 1 kgm of work, maximum oxygen consumption per 1 kg body mass during muscular exertion, effectiveness of work) were studied before and after operation. The data obtained were compared with the results of spiroergometry in 175 patients with various lesions of the coronary arteries identified by coronarography and in 50 healthy individuals. Spiroergometry is an effective method for diagnosing coronary atherosclerosis before performing coronarography. Patients with good postoperative results showed values which were close to normal; in poor results of surgery and in thrombosis of the coronary shunts initial values characteristic of atherosclertoic involvement of the coronary arteries are encountered. Increase of the effectiveness of work to normal, decrease in oxygen expediture per 1 kgm of work, diminution of maximum oxygen consumption per 1 kg body mass during muscular exertion in the remote postoperative period make it possible to presume, before performing coronarography, that the shunts are functioning. The study conducted allow bicycle ergometry and spiroergometry to be considered demonstrative functional methods for appraising the remote results of operation.

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.

The effect of coronary flow recovery and/or aneurism resection on the pattern of conductivity disorders was examined in 76, and that of excitability disorders, in 35 patients. Aortal-coronary shunting eliminated ventricular extrasystole in 13 of 17 patients, normalized conductive function in all 12 patients with transitory block of the His bundle's anterior left branch, while their general clinical condition improved. Functional conductivity and excitability disorders due to scarry myocardial changes persisted in spite of revascularization procedure. Following aneurism resection, cardiac rhythm returned to normal in 5 of the 7 patients with ventricular extrasystole, while in 2 patients with paroxysmal atrial fibrillation paroxysms disappeared, a fact attributable to the removal of ectopic excitement focus and improved intracardiac hemodynamics. In all cases, conductivity and excitability improvement and normalization occurred during the early postoperative period and were maintained for long terms (up to ten years).

Remote results of the aorto-coronary shunting operation performed in 102 patients with ischemic heart disease are reported. Of this number 75 suffered from severe angina pectoris at rest, while the others had angina pectoris on effort of some or other degree of intensity. An excellent late result was achieved (over periods from 6 months to 5 years) in 33.3, good--in 49.5, satisfactory--in 10.1% of the cases, with the surgery being of no avail in 5.1 and aggravating the patients' condition in 2.0% of the instances. Excellent and good results were obtained in 83% of the cases, viz. disappearance of angina pectoris, improved ECG at rest and on effort. The excellent and good results did not depend on the initial coronary reserve, the degree of the coronaries lesion and on the adequacy of the operation, whereas all the other results (satisfactory, ineffective, deterioration) were seen, as a rule, with an inadequate aorto-coronary shunting in patients with extensive cicatricial changes of the myocardium. A direct relationship between remote results and the extent of the myocardial lesion was established.

The cardio-respiratory system in 50 healthy subjects and 58 patients with renal hypertension was examined using bicycle spiroergometry at rest and after exercise, before and after the reconstructive surgery on renal arteries and following rehabilitational postoperative treatment by physical training. Before surgery the patients showed excessive pressor response to exercises, ECG signs of overload and hypertrophy of the left ventricle and atrium increasing during exercise, decreased oxygenation of the tissues, decreased compensatory and adaptive capacity. After the operation AD at rest decreased, aerobic reserve improved, while chronotropic cardiac reserve aggravated, and pronounced dystonia was noted. After certain physical training decreased pressor responses, significant increase of tolerance to exercise as well as elevation of the aerobic reserve up to that in the trained persons were observed.

Observations of 234 patients after aorto-coronary shunting performed at the All-Union Surgical Center, Academy of Medical Sciences of the USSR led to conclusion that sanatorium rehabilitation treatment after the operation leads to increased tolerance to exercise: up to 80-100 W it was enhanced in 171 patients (71%) of the main group and only in 63 (21%) in the control group. In the main group 68% of patients returned to work and only 45% in the control group. These data point to the efficacy of the sanatorium rehabilitation after aorto-coronary shunting.

The paper provides data of a ten-year follow-up of 51 patients who underwent postinfarction left ventricular aneurysmectomy in the All-Union Surgery Research Center with a view to verifying the degree of working capacity loss. In the long-term period, out of them 37 persons (72.5%) had Group II disability, 10 (19.6%) had easier managerial jobs (4 persons (7.8%) had not worked before surgery) and 3 (5.9%) retired on their old-age pension. The surgical therapy for postinfarction cardiac aneurysm significantly improves the functional status and physical working capacity in 72.5% of the patients.