Hibernating myocardium in heart failure

Ischemic left ventricular systolic dysfunction may result from myocardial necrosis or from hypocontractile areas of viable myocardium. In some cases, recovery of contractility may occur on revascularization--this reversibly dysfunctional tissue is commonly referred to as hibernating myocardium. Observational data suggest that revascularization of patients with ischemic left ventricular systolic dysfunction and known viable myocardium provides a survival benefit over medical therapy. Identification of viable, dysfunctional myocardium may be especially worthwhile in deciding which patients with ischemic left ventricular systolic dysfunction will benefit from revascularization procedures. Randomized, prospective trials evaluating this are currently ongoing. This review will provide an overview of the complex pathophysiology of viable, dysfunctional myocardium, and will discuss outcomes after revascularization. Of the techniques used to determine the presence of hibernating myocardium, functional methods such as stress echocardiography and cardiac magnetic resonance appear more specific, but less sensitive, than the nuclear modalities, which assess perfusion and metabolic activity. Currently, the availability of all methods is variable.     

The dynamics of lethality and causes of death of the burned for the last 40 years in the Russian Burn Center of Ministry of Health of the Russian Federation

A comparative analysis of lethality and causes of death of the burned in the Russian Burn Center of Ministry of Health of the Russian Federation for 40 years has shown that general lethality in the Burn Center for this period did not undergo substantial changes and was within 10%. Main causes of death were shock, sepsis and pneumonia. Other causes were of less significance. The authors noted more severe thermal traumas in the nineties and earlier development of complications leading to death.     

Acetabular bone grafting in primary total hip arthroplasty]

A group of 108 hips in 102 patients (81 females and 21 males; average age: 66.9 years) operated at our Centre between 1989 and 1998 was evaluated. There were 76 hips with idiopathic arthritis, 21 hips with rheumatoid arthritis, 2 hips with post-traumatic lesions and 9 cases of dysplastic arthritis of the hip. Cemented total hip arthroplasty was performed in all cases (62 Weller prostheses, 28 Charnley prostheses, 12 Ultima-Straight prostheses and 6 Centrament prostheses). In the presented material three different kinds of bone grafting were performed: "impaction bone grafting" with autogenous cancellous bone grafts in cases of bone cysts and cavitary lesions (57 cases); augmentation of thin sclerotic or protrusive acetabulums with autogenous cancellous bone grafts with or without allogenous cancellous bone grafts (26 and 16 cases respectively); and reconstruction of the roof of the acetabulum with autogenic cortico-cancellous bone grafts 9 cases). In 17% cases autogenous and allogenous bone grafts were used simultaneously and in 83% autogenous bone grafts only were employed. Acetabular bone grafting was necessary to create proper bone substrate for endoprostheses implantation. Evaluation of results was based on criteria proposed by a joint committee of The Hip Society, SICOT and AAOS. A mean of 83.5% points were achieved in the Harris Hip Score. Aseptic loosening was observed in 15 sockets and 9 stems. Bone grafts didn't heal in 25 hips, of which 14 had loose sockets. These results are comparable to those in primary total hip arthroplasties without acetabular bone grafting. The results in the presented paper support the opinion that acetabular bone grafting is a useful tool in reconstructive surgery of the hip and allows to achieve good results in technically difficult acetabuli.     

Subvastus and medial parapatellar approaches in TKA: comparison of functional results

The purpose of this study was to compare the clinical results of total knee arthroplasty (TKA) in the early and late postoperative period using subvastus and medial parapatellar approach. A prospective randomized controlled study was conducted in a group of 169 patients (180 TKAs) with 2-year follow-up. Patients were divided into a study group (97 TKAs) with a subvastus approach and a control group (83 TKAs) with a parapatellar approach. Assessment of the results of both operating approaches was based on functional, clinical Knee Society Score, and pain (visual analog scale). Patients in the subvastus group achieved full active extension, better range of motion, and better Knee Society Score results at 12 days, 6 weeks, and 12 weeks earlier than patients in the medial parapatellar group. They also had less pain at 12 days. No statistically significant differences existed between assessed end points in both groups at 24- and 52-weeks, and 24-months postoperatively. The subvastus approach has given patients better early clinical results; however, at longer follow-up, both groups had similar outcomes. The potential benefits of the subvastus approach are: protection of the extensor mechanism from damage, less risk of damaging the blood supply to the patella, earlier clinical recovery, and less pain in the early postoperative period. The subvastus approach is an alternative to the standard medial parapatellar approach in TKA. It can be used with equally good results, especially taking into consideration positive clinical aspects in the early postoperative period.     

Rheumatoid disease and ischaemic heart disease: insights from pathophysiology and vascular biology

Rheumatoid disease (RD) is a multisystem inflammatory disorder, which is associated with an increased cardiovascular mortality, thought to be due to ischaemic heart disease (IHD). The precise mechanisms causing increased IHD in RD are unclear. However, there is increasing recognition that atherosclerosis is another chronic inflammatory condition, which shares several pathophysiological features with RD. For example, endothelial damage/dysfunction, platelet activation, hypercoagulability and angiogenesis are well-recognised in both disease processes. Furthermore, RD may influence traditional risk factors such as dyslipidaemia. Although the exact reasons for the increased ischaemic burden are unclear, physicians should place a high priority upon reducing cardiovascular risk in sufferers of RD. This review summarises factors that might contribute to the pathogenesis of IHD in RD. Discussion will focus upon features shared by atherosclerotic and rheumatoid processes, as well as possible interactions between RD and conventional IHD risk factors.     

Gastric blood flow following simultaneous administration of serotonin and histamine

Summary Left gastric-artery flow was measured with a Medicon FM-6 gated sine-wave electromagnetic flowmeter. Histamine, 4 µg./min., produces a small increase (9%) in flow. Serotonin in increasing doses of 10, 20, 40, and 60 µg./kg./min. given concomitantly with the same dose of histamine, progressively augment left gastric-artery flow in increments of 25, 43, 87, and 189%, respectively. The increases in left gastric-artery flow found with increasing doses of serotonin represent a single, direct, exponential relationship.Supported by U.S.P.H.S. Grant AM-02150 and by the Donald J. Cowling Fund for Surgical Research.     

Manufacturing medical instruments by friction welding

Biomedical Engineering -