Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The biochemical effects of peripheral vascular disease on skeletal muscle have not been characterized precisely because of the lack of satisfactory noninvasive analytic methods. 31P nuclear magnetic resonance (NMR) spectroscopy was used to measure the high-energy phosphate compounds, phosphocreatine (PCr) and adenosine triphosphate, as well as metabolic byproducts, such as inorganic phosphates (Pi) and phosphate monoesters in calf muscles of 214 limbs with peripheral vascular disease. Intracellular pH was also measured. The NMR index (Pi[PCr + Pi]) was used to quantitate the impairment of oxidative phosphorylation as a result of ischemia. Studies done at rest documented the impairment of oxidative metabolism only in limbs with severe ischemia (ankle-brachial pressure index (API) less than 0.4). Exercise resulted in a significant elevation of the NMR index in all limbs and the rate of return of this value toward normal following exercise was prolonged even in limbs with moderate ischemia (0.4 less than or equal to API less than or equal to 0.9). Correlation of 31P NMR parameters with arteriograms showed that infrapopliteal occlusions resulted in prolonged recovery times only when the superficial femoral artery was occluded and emphasized the metabolic consequences of multisegmental disease. Accumulation of glycolytic pathway intermediates correlated with the decrease in muscle cell pH observed with exercise. Despite immediate improvement in symptoms and hemodynamic parameters following revascularization, return to normal biochemical function occurs over a prolonged period of time. This study demonstrates that 31P NMR spectroscopy can successfully measure noninvasively the important phosphorus-containing compounds involved in the bioenergetics of skeletal muscle in vivo rapidly enough to permit real-time determination during exercise and recovery.
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PMID:31P nuclear magnetic resonance spectroscopy: noninvasive biochemical analysis of the ischemic extremity. 293 3

The outcome in 299 patients having 321 percutaneous transluminal angioplasty (PTA) procedures for peripheral vascular disease was analysed. Technical failure occurred in 21 patients (7%) but in none was the limb ischemia made worse by the failed PTA attempt; nine of these (3%) had been considered unsuitable for arterial reconstruction and proceeded to primary amputation, while 12 (4%) did not have subsequent management compromised by the failed PTA attempt. Complications occurred in seven patients (2.3%); four of these (1.3%) had worsening ischemia but were able to be satisfactorily managed by surgical intervention. There were 71 patients (23.7%) who had an initially successful PTA procedure which subsequently failed; 20 of these (6.7%) had been considered unsuitable for arterial reconstruction and proceeded to amputation, while five patients suitable for arterial reconstruction (1.7%) came to amputation, four following failed bypass surgery and one following multiple trauma from a motor vehicle accident. The remaining 46 patients (15.3%) did not have subsequent management compromised by the late failure of PTA. Early and late failure of PTA in patients presenting with peripheral vascular disease does not compromise subsequent management.
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PMID:Outcome in patients with failed percutaneous transluminal angioplasty for peripheral vascular disease. 297 49

Transcutaneous oxygen tension (TcPO2) was measured through Clark's electrode at the dorsum of the foot in 52 healthy controls whose ages ranged from twenty to sixty-five years (mean 45.05 +/- 14.09) and 36 nondiabetic patients with peripheral vascular disease (PVD) (5 stage I, 16 stage II, 4 stage III, 11 stage IV), under standardized conditions at rest and during recovery from limb ischemia obtained with pneumatic cuff compression for 3 minutes. At rest the TcPO2 averaged 71.20 +/- 14.26 mm Hg (range 46-92) in the controls and 51.56 +/- 26.38 in the PVD patients (p less than .01). A wide overlap was observed between the two groups and among the different stages of the disease, and consequently, the diagnostic value of TcPO2 at rest was limited (sensitivity equal to 32%). During the recovery from ischemia the time constant (recovery half-time, T1/2) averaged 38.01 +/- 7.23 sec in the controls and 55.84 +/- 19.82 in the PVD patients (p less than .01). The T1/2 added to the diagnostic value of the method, making it more sensitive (55%), especially for stage II patients. The TcPO2 at rest was lower with increasing severity of the disease; both the TcPO2 at rest and the T1/2 correlated with the ankle-arm pressure index in the diseased limbs (r = .48 and -.41 respectively, p less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Transcutaneous oxygen tension (TcPO2) measurement as a diagnostic tool in patients with peripheral vascular disease. 317 54

We hypothesized that chronic ischemia of peripheral vascular disease would lead to increased thromboxane A2 (TxA2) and decreased prostacyclin (PGI2) production and surgical correction of the ischemia would stabilize TxA2 and PGI2 at normal levels. TxA2 and PGI2 concentrations were determined in 22 patients before, during, and after arterial reconstruction for limb salvage and in 10 control subjects. Control samples and preoperative patient samples had no detectable TxA2 or PGI2 (less than 26 pg/ml). Five minutes after reperfusion TxA2 increased (TxA2 = 76.27 +/- 48.9 pg/ml, mean +/- SEM) and persisted at 1 day (TxA2 = 190.1 +/- 80.1 pg/ml), 2 days (TxA2 = 224.7 +/- 131.7 pg/ml), 5 days (TxA2 = 334.8 +/- 272.8 pg/ml), and 7 days postoperatively (TxA2 = 256.6 +/- 149.0 pg/ml). Elevated TxA2 production was not associated with chronic ischemia of peripheral vascular disease. Reperfusion of the severely ischemic limb caused significant TxA2 release.
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PMID:Thromboxane release after reperfusion of chronically ischemic limbs in patients. 328 Aug 35

Metabolic and clinical peculiarities of patients with peripheral vascular disease (PVD) were evaluated in two studies. In the first study lipid and lipoprotein composition of 20 patients with PVD were examined. Twelve of these patients were normolipidemic, the other 8 hypertriglyceridemic. Ten normolipidemic and ten hyperlipidemic age-matched subjects served as controls. High density lipoprotein cholesterol (HDL-C) levels were markedly reduced in the hypertriglyceridemic, both with (35.1 +/- 5.0 mg/dl) and without (36.2 +/- 11.7 mg/dl) PVD as compared to the normolipidemic patients (47.0 +/- 6.3 mg/dl) and controls (48.1 +/- 10 mg/dl). All the PVD patients showed an increased apolipoprotein B content in the very low density lipoproteins (VLDL) as compared to controls (p less than 0.001). A significant correlation between VLDL-cholesterol and apo B levels was detected in both groups; however, two distinct populations could be clearly separated (slopes of the regression lines: PVD patients = 0.350; controls = 0.215, p less than 0.0001). These data suggest a possible discriminatory power of VLDL-apo B levels in PVD patients independent of other metabolic parameters. In the second study, the clinical activity of metformin (N, N-dimethylbiguanide) a widely used antidiabetic agent, on arterial blood flow was evaluated in 15 patients with PVD. Flow was determined by quantitative strain-gauge plethysmography during a cross-over trial, comparing 6 months of drug and placebo administration. Metformin (850 mg tid) significantly increased arterial flow after a standardized ischemia in both sequences. In spite of the minimal changes of plasma lipid levels during metformin, a highly significant increase of HDL-C levels (+8.3% during the whole treatment) was demonstrated. Plasma levels of isoprotein AI-1 were also raised during the metformin period. Although the mechanism/s of the beneficial effects of metformin on flow cannot, at present be defined, the reported results underline the significant therapeutic potential of this metabolic drug treatment in PVD.
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PMID:Metabolic approach to the diagnosis and treatment of atherosclerotic peripheral vascular disease. 333 Jan 15

There is little information available concerning the alterations in skeletal muscle energy metabolism which occur in response to chronic arterial occlusive disease. In addition, the effect of arterial reconstruction on skeletal muscle energy metabolism in patients with peripheral vascular disease has not been defined. Needle biopsies were obtained from the quadriceps femoris muscle of 7 patients with aortoiliac disease and 15 patients with femoropopliteal disease and from the gastrocnemius muscle of 9 patients with femoropopliteal disease. Muscle samples were analyzed for ATP, ADP, AMP, phosphocreatine, creatine, and lactate. Eleven patients were rebiopsied after vascular reconstruction. Patients with rest pain had decreased total adenine nucleotides, energy charge potential, and ATP/ADP ratios as compared to those of controls. ATP levels were significantly decreased in muscle samples obtained distal to the arterial occlusion (i.e., quadriceps/aortoiliac, gastrocnemius/femoropopliteal) in patients with rest pain (compared with controls). ATP levels did not differ significantly from those of controls in muscle samples obtained from patients with claudication. However, energy charge potential was significantly decreased in all patients with claudication regardless of biopsy site and location of arterial occlusive disease. Normalization of muscle energy metabolism was not demonstrated following arterial reconstruction. We conclude that resting skeletal muscle energy metabolism is abnormal in patients with chronic arterial insufficiency and that progression of disease toward more severe ischemia is associated with more marked derangement. Whether the possible beneficial effects of revascularization on muscle energy metabolism are masked by the concurrent effect of injury in the early postoperative period remains to be clarified.
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PMID:Muscle high energy phosphates in chronic peripheral vascular disease. 334 25

The effects of adenosine on central and myocardial hemodynamics and metabolism were evaluated during fentanyl anesthesia (100 micrograms.kg-1) in six patients with peripheral vascular disease. Adenosine was intravenously infused, at a rate of 90 +/- 20 (SEM) micrograms.kg-1.min-1, to reduce mean arterial blood pressure by approximately 20% (23 +/- 2% SEM, from 82 +/- 3 to 63 +/- 3 SEM mmHg) during a 20-min period. Systemic and pulmonary vascular resistance indices decreased by 36 +/- 3 and 32 +/- 6% (SEM), and cardiac index increased by 18 +/- 5%. Heart rate, ventricular filling pressures, and whole body oxygen consumption were not affected by adenosine. Despite the reduced mean arterial blood pressure, coronary sinus flow increased by 128 +/- 26% (SEM) in parallel with a 96 +/- 11% (SEM) increase in coronary sinus oxygen content. Left and right ventricular stroke work indices, as well as myocardial oxygen consumption, were maintained. ECG (12-lead) demonstrated signs of ischemia in one subject, while myocardial lactate uptake was unchanged in all subjects. In conclusion, adenosine-induced hypotension in patients with peripheral vascular disease increased cardiac index without affecting myocardial work, whole body, and myocardial oxygen consumptions. The marked increase in coronary sinus blood flow, indicating coronary vasodilation, was not related to increased myocardial work. Further information regarding myocardial effect of adenosine in patients with ischemic heart disease is warranted.
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PMID:Effects of adenosine-induced hypotension on myocardial hemodynamics and metabolism in fentanyl anesthetized patients with peripheral vascular disease. 334 97

Although chronic mesenteric ischemia is an infrequent, even rare, condition and a busy vascular surgeon may encounter only one such patient in a year, the associated morbidity and mortality are high, especially if the condition is not recognized. General and vascular surgeons must bear in mind the triad of postprandial pain, weight loss and diarrhea. Patients with mesenteric ischemia are at high risk and generally have diffuse peripheral vascular disease. Although surgery is hazardous, successful repair can result in long-term survival without morbidity. The author favours antegrade supraceliac bypass grafting over infrarenal grafting which is technically more difficult.
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PMID:Chronic mesenteric ischemia. 336 11

Surgical risk factors of abdominal aortic disease. Between January 1, 1982 and October 1986, 327 surgical repairs were performed on abdominal aortic obstructive diseases and aneurysms at the St. Luc University Hospital. 150 pre-, per- and postoperative data were collected retrospectively for each patient. Ninety-one per cent of patients were smokers, 57.5 per cent had heart disease, 43 per cent arterial hypertension, 51 per cent peripheral vascular disease and 28 percent had obstructive lung disease. Concerning cardiac morbidity, the post-operative infarction rate was 4.4 per cent in patients who had previously suffered from an infarction, and 1.9 per cent in patients with no previous infarction. Post-operative angina-ischemia rate were respectively 23 and 4.7 per cent. Two hundred and thirty two elective operations resulted in 6 deaths (2.6 per cent) while 95 emergency operations resulted in 34 deaths (35.8 per cent). The causes of the death and the post-operative complications are detailed. The decrease of the morbidity and the mortality rates inherent to this pathology depends on an early diagnosis and surgical treatment by a team, knowledgeable of this pathology, who are able to prevent and correctly treat the complications, especially those affecting the cardiovascular system.
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PMID:[Risk factors in surgery of the abdominal aorta]. 338 30

Magnetic resonance spectroscopy can be used to characterize the bioenergetic state of the musculoskeletal system, and several marker compounds related to the tissue's biochemistry have been found to exist. Potential new techniques involving better spatial localization, spectral editing, and examination of nuclei other than phosphorus are in the developmental stage. Their development over the next few years will determine the extent to which MRS will become a universally used medical tool. However, the results with 31P alone guarantee a continued role in the study of muscular disease, peripheral vascular disease, and hypoxia and ischemia of the neonatal brain.
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PMID:Magnetic resonance spectroscopy of the musculoskeletal system. 345 10


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