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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hypertrophic cardiomyopathy (HCM) is a primary myocardial disease of unknown cause that is characterized by a hypertrophied, nondilated, hypercontractile left ventricle. Its etiology and pathogenesis remain undefined but the three principal factors implicated are a genetic predisposition, a hypersensitivity to catecholamines, and an abnormal calcium metabolism. The hypertrophy typically involves the intraventricular septum to varying degrees, but may also involve the apex or free wall and even be concentric. The disease occurs in either an obstructive or a nonobstructive form depending on whether an intraventricular pressure gradient can be demonstrated at rest or on provocation. The gradient and obstruction to outflow is usually seen in patients with asymmetric septal hypertrophy (ASH) and anterior motion of the mitral valve during systole (SAM). Abnormal left ventricular diastolic function characterized by inadequate filling and impaired relaxation has been shown to be very important in both the obstructive and nonobstructive forms of the disease. In addition, inadequate coronary vasodilator reserve as a result of small vessel disease, microvascular spasm, and/or low capillary density per unit myocardial mass has been implicated as an important cause of ischemia in patients without coronary artery disease. HCM is a disease of young adulthood with relatively slow progression; young patients are often asymptomatic, whereas older patients are more limited by dyspnea, angina, dizziness, or syncope. Supraventricular tachyarrhythmias occur in 30% of patients, and high-grade ventricular arrhythmias occur in over 75%. The annual mortality is 3-5%. The common mode of demise is sudden cardiac death. Therefore, the primary objectives of treatment are the amelioration of symptoms, the control of arrhythmias, and the prevention of sudden death. Beta-adrenoreceptor blocking agents decrease myocardial contractility and oxygen demands and increase ventricular volume; therefore, they are most useful in patients with the obstructive form of HCM. Calcium channel antagonists enhance left ventricular relaxation, relieve microvascular spasm, and improve coronary filling and therefore are the agents of choice in patients with diastolic dysfunction. The ability of the calcium channel antagonists to decrease contractility makes them valuable in patients with obstructive HCM. Arterial vasodilators, diuretics, nitrates, and inotropic agents should be avoided because they can increase the intraventricular gradient. Myomyectomy is reserved for those patients with the obstructive form of HCM whose symptoms are refractory to medical therapy.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Hypertrophic cardiomyopathy: current views on etiology, pathophysiology, and management. 331 Jun 37

Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation.
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PMID:Intra-arterial thrombolysis for acute limb ischemia: a three-year experience. 356 82

A total of 106 lesions due to vascular injuries (noniatrogenic) to limbs were treated in 81 patients at the CHR, Rennes (Cardiovascular and Thoracic Unit) between 1970 and 1983. Analysis of data allowed a profile of arterial lesions (type and location) to be retraced, and demonstrated the high frequency of associated lesions, these varying in distribution according to whether the upper limbs (major seriousness of neurologic sequelae) or lower limbs (very high incidence of osteoarticular lesions) were involved. Among the "immutable" severity factors (related to the injury) emphasis has to be placed on "contending or crush injuries", widely displaced lesions, extensive arterial dilacerations (middle segments of limbs) and multiple vascular lesions. This study focused attention mainly on the tactical and technical factors allowing improvement in the always reserved prognosis of these lesions. Firstly, by maximum reduction in the duration of ischemia by early diagnosis (to avoid referral to a "second hand") and by judicious indication for angiography (conducted preferably in the operation room and if necessary repeated after vascular repair surgery). Secondly, by repair of lesions in conformity with well established rules and principles: bone stabilization initially, formal venous repair surgery for large venous trunks, preferably "conservative" surgery of arterial vessels to ensure a perfect result initially (any recovery operation results in a very high incidence of failures).
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PMID:[Vascular injuries of the limbs. Evaluation of 106 lesions in 76 patients]. 370 Apr 97

The most common cause of intermittent claudication is atherosclerotic occlusive arterial disease. Differentiation of the common musculoskeletal and neurologic conditions that may mimic intermittent claudication is often possible with a careful history, but when insufficient detail is provided or multiple conditions exist, the findings on physical examination and noninvasive studies are useful. While physical examination provides a rough estimate of the degree of ischemia, assessment of functional impairment produced by occlusive arterial disease is best made with noninvasive studies before and after standard exercise. Arteriography is reserved for the patient for whom restoration of pulsatile flow is planned.
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PMID:Evaluation of the patient with intermittent claudication. 402 47

Low dose urokinase-lys plasminogen was used to treat 10 patients with acute ischemia of lower limbs. Preliminary results are reported and indications defined, the combination producing effective relief and being very well tolerated biologically and clinically. All patients presented clear signs of ischemia provoking a short term risk for the limb. Direct femoral puncture arteriography of the ischemic limb was an essential pretreatment investigation. A thin catheter left in contact with the thrombus allowed localized fibrinolysis to be performed. Follow up arteriography examinations assessed clinicopathologic results, while biologic surveillance of principal coagulation parameters showed a lack of significant alterations during treatment. Ischemic signs were totally relieved in 7 cases, with arterial repermeabilization allowing recuperation of one (3 cases) or both (2 cases) distal pulses. Persistence of a popliteal thrombus in one case required a fogarty after a direct approach and the limb was saved. Two patients had to be amputated because of delayed treatment. These encouraging results suggest that this procedure of local thrombolysis be reserved for popliteal or infra-popliteal occlusions accompanied by sensory-motor signs and of recent (less than 72 hours) onset. Follow up for 8 months is insufficient but has shown the absence of deterioration, but this is obviously a function of the natural course of the underlying atheromatous disease.
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PMID:[Indications and results of combined urokinase-lys plasminogen in acute ischemic pathology of the legs]. 409 20

The beta-blocker trials published so far may be subdivided into three different categories: 1) retrospective, 2) prospective non-conclusive, 3) prospective conclusive studies. The retrospective studies suffer the weaknesses of the retrospective method and may only be used as supportive evidence. There have so far been four prospective studies producing positive results, three with alprenolol and one with practolol. The studies presented support the concept that practolol and alprenolol reduce the long-term mortality due to sudden death from ischemic heart disease after myocardial infarction. All the studies have been criticized on various grounds and a list of unanswered remaining issues may be made. Acute and long-term effects of betablockade need not be the same. Our knowledge about the necessary doses and plasma levels is incomplete. All the studies published so far cover a maximum period of two years. If the study observation periods were prolonged it is likely that at some time the relative benefit becomes less. Ideal treatment should be reserved for those patients likely to derive significant benefit from it. At the present time identification of such patients is not sufficiently precise. Whether or not the beta-blockers have an antiarrhythmic effect, for instance demonstrated on chronic PVC's, this information is of little value in interpreting the proper mechanism of the beta-blockers in acute ischemia and lethal arrhythmias. In order to contribute new knowledge future studies should involve sufficiently large numbers of representative groups of patients, a stratified study design and a beta-blocker with ancillary properties different from alprenolol.
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PMID:Beta blockers after myocardial infarction--aspects on study design based on current knowledge. 611 77

Nine cases of acute acalculous cholecystitis were diagnosed in the surgical intensive care unit at Hartford Hospital during a 2 year period after abdominal, cardiovascular, and traumatic surgery. A tender mass in the right upper quadrant was suggestive but not diagnostic of the condition. Hyperamylasemia was seen in all patients. Ultrasonography is the most useful diagnostic tool; serial studies reveal progressive gallbladder dilatation and edema. Tube cholecystostomy was used in five patients and cholecystectomy in four. Cholecystostomy led to resolution of the inflammatory process in all five patients. Cholecystectomy should be reserved for those patients with extensive gallbladder necrosis. Six of the nine patients in the series died, all from multiple systems failure with concomitant sepsis. Hypotension is probably central to the development of acute acalculous cholecystitis. In the face of elevated intraluminal gallbladder pressure caused by ampullary edema and increased bile viscosity, hypotension may result in mucosal ischemia and necrosis with subsequent bacterial colonization. Acute acalculous cholecystitis represents another organ failure in critically ill patients who are experiencing progressive failure of multiple organ systems. An aggressive approach to the manifestations of organ failure, including acalculous cholecystitis, must be employed.
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PMID:Acute acalculous cholecystitis in the critically ill patient. 618 83

Effort angina is the result of acute myocardial ischemia on exercise due to an imbalance between myocardial oxygen demand and supply. During exercise, ischemia is provoked by an increase in myocardial oxygen needs (tachycardia, increased blood pressure, etc.) which cannot be met by increased coronary blood flow. The commonest cause of insufficient flow is coronary atherosclerosis. Coronary spasm does, however, play a role, whether it occurs during exercise on normal or atheromatous coronary vessels. Classical anti-anginal therapy is directed towards a reduction in the intense adrenergic activity associated with exercise, and to the limitation of myocardial oxygen consumption. Calcium inhibitors which cause peripheral vasodilation, decrease ventricular wall tension and coronary resistance, are usually reserved for unstable or resistant angina. We studied 10 patients with stable effort angina for over 2 years with significant (greater than 70 per cent) atheromatous lesions on coronary angiography unsuitable for surgical treatment. The patients underwent a randomised double blind trial to compare the effects of propranolol, diltiazem and placebo. Exercise ECG was performed after a treatment period of one week, 3 hours after drug administration. The results showed a significant improvement of work capacity with propranolol and diltiazem as compared to placebo. Propranolol (160 mg/day) was more effective than diltiazem (180 mg/day) in 6 patients. In 4 cases, the improvement with diltiazem and propranolol was the same. The association of the two drugs in one open study in 5 patients was even more effective in 3 patients. The small number of patients studied makes it impossible to draw any firm conclusions. Although calcium inhibitors are the treatment of choice in coronary spasm and betablockers in effort angina, diltiazem exerts an anti-anginal effect by reduction of myocardial oxygen consumption without depression of myocardial contractility, as other workers have shown.
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PMID:[Are calcium inhibitors useful in the treatment of effort angina pectoris]. 640 53

Isobutyl-2 cyanoacrylate (IBC) was used to embolize the bronchial arteries of 14 patients with severe hemoptysis. The site of bleeding was supplied by a bronchial artery from the aorta in 11 cases and from a right bronchointercostal trunk in three. IBC was injected after previous reduction of the blood flow in the artery by embolization with particles of dura mater. In all cases, bleeding stopped immediately after occlusion and no spinal cord complications were observed. The results indicate that IBC may be a valuable occluding agent in severe hemoptysis, since it produced virtually permanent occlusion of both the distal and proximal parts of the artery. In 13 patients, bleeding did not recur throughout follow-up periods of 2-17 months. In one patient, it recurred 12 months after embolization but stopped after occlusion of another bronchial artery with IBC. It should be noted, however, that immediately after embolization, five patients experienced violent transient retrosternal burning, and one patient experienced dysphagia and fever for 2 days. Since mediastinal ischemia cannot always be avoided, this procedure must be reserved for cases of severe hemoptysis for which surgical treatment is contraindicated.
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PMID:Bronchial artery occlusion for severe hemoptysis: use of isobutyl-2 cyanoacrylate. 660 May 35

The main and most attractive surgical measure in acute coronary disease is emergency revascularisation of acute ischemia. As far as unstable angina is concerned, the recommendations of the National Cooperative Study Group are more or less universally accepted, which means that emergency revascularisation is reserved for patients in whom stabilisation of angina with vigorous medical treatment is unsuccessful. On the other hand, it has been shown that a large proportion of patients in whom unstable angina had been successfully stabilized subsequently suffered from severe chronic angina. The author therefore recommends performing coronarography in all younger patients within a few days. If left main stem or three-vessel disease is documented by this investigation, aortocoronary bypass should be performed during the same hospitalisation. In cases with isolated proximal stenosis of the left anterior descending artery, transluminal dilatation should be considered. The author's own results confirm the general experience that revascularisation for unstable angina does not involve elevated risk. After established acute infarction, the role of surgery is confined to treatment of severe mechanical complications of infarction (acute aneurysm, ventricular septal defect, subvalvular mitral insufficiency) and aortocoronary bypass for postinfarction angina. The author's results show that early and late mortality are rather high, though a good late result can be achieved in about 50% of the cases. However, in view of the poor prognosis under conservative treatment, even this modest rate of success seems acceptable.
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PMID:[Surgical treatment of acute coronary heart disease]. 661 Sep 37


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