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

The quantitative VCG criteria (VCGer) for left ventricular hypertrophy (LVH) and their diagnostic power were determined in 165 hypertensive men and 86 women over 40 years of age without congestive cardiac failure in comparison with 91 normal men and 108 normal women. The patients were grouped according to the presence or absence of LVH determined by X-ray (men: 96 without and 69 with LVH, women: 41 without and 45 with LVH). The proper statistical methods were used taking into account whether their distributions were symmetrical or asymmetrical. We found some sex differences of VCG criteria. The most striking results were the lack of increased voltage, and the great sensitivity of the orientation of Q vectors to the left (Q left). Q left may be induced by: 1. a septal hypertrophy, alone or accompanied by a hypertrophy of the anterior and posterior paraseptal regions of LV wall, 2. by a subendocardial ischemia at these levels induced by the increase of intraventricular pressure, 3. by possible spatial change of the septum, 4. by all these factors acting synchronously, 5. by other, unknown factors. These VCGcr for LVH found by us are different from those in the literature, but they are valid in Romania.
 ...
PMID:Absence of increased cardiac voltage and the importance of Q vectors for the diagnosis of left ventricular hypertrophy in early stages of hypertension in patients over 40 years of age. 623 49

Portal hypertension is defined as an increase of the portal venous pressure over 20 cm H2O or 7 mm Hg, respectively. It may be induced by different types of portal venous stenosis or obstruction, primarily by cirrhosis and fibrosis of the liver and, less frequent by posthepatic disorders such as the Budd-Chiari-syndrome or congestive heart failure. Portal hypertension is followed by ectasia and phlebosclerosis of the portal vein, by splenomegaly, ascites and by various types of collateral circulation. Among these, oesophageal varices, are most important since they often lead to acute upper gastrointestinal haemorrhage, the major complication of portal hypertension. Bleeding from oesophaeal varices is essentially based on atrophy of the squamous epithelium, caused by ischemia from local hypoxia and venous stasis. Portal hypertension and the frequently compromised blood clotting mechanism due to reduced synthesis of clotting factors in the liver aggravate the bleeding. Atrophy of the esophageal mucosa presents an area of decreased resistance likely to ulcerate with easy erosion of the varices--usually lying very superficially--; with mechanical irritation by food or peptic erosion from gastroesophageal reflux being frequent inducers of hemorrhage.
 ...
PMID:[Pathologic-anatomic reflections on portal hypertension (author's transl)]. 624 21

Initial studies from our institution demonstrated beneficial anti-ischemic effects of short-term infusion of intravenous nitroglycerin in patients with acute myocardial infarction. At lower doses, nitroglycerin was shown to be principally a venodilator; at higher doses, a mixed venous and arterial dilating effect was demonstrated. The acute hemodynamic effects of nitroglycerin varied in the presence or absence of left ventricular failure; patients with the most severe degree of left ventricular dysfunction had the most beneficial hemodynamic effect. Similar differential effects have been demonstrated for nitroprusside in other studies. A comparison of the arterial vasodilating potency of nitroglycerin and nitroprusside in patients in whom acute hypertension develops following coronary artery bypass surgery revealed that equal lowering of arterial pressure and systemic vascular resistance could be demonstrated in 85 percent of the patients with comparable infusion rates. Review of previous clinical and laboratory studies in animals, in which the effects of nitroglycerin and nitroprusside were compared, in most cases revealed opposite effects on intercoronary collateral flow and, thereby, opposite effects on the severity of regional ischemia. Our recently completed randomized placebo-controlled clinical trial employing a 48-hour infusion of nitroglycerin demonstrated a higher incidence of significant improvement in abnormalities noted on scintigraphy when nitroglycerin treatment was initiated within 10 hours of the onset of symptoms. Beneficial effects of early nitroglycerin treatment have also been demonstrated in previous clinical trials. In similar studies, which utilized nitroprusside infusions in patients with acute myocardial infarction, some investigators found an increase in short-term mortality with early nitroprusside treatment whereas others found benefit. The uniformly favorable results of the clinical trials that utilized intravenous nitroglycerin, although not necessarily supporting its routine use in all patients, would support a preference for nitroglycerin over nitroprusside for the treatment of congestive heart failure and/or acute hypertension complicating acute myocardial infarction.
 ...
PMID:Comparison of intravenous nitroglycerin and sodium nitroprusside in acute myocardial infarction. 640 15

Left-sided congestive heart failure may be secondary to decreased left ventricular myocardial compliance in some patients. To investigate the anatomic basis for altered wall stiffness, morphometric determinations of muscle cell nuclear density and percent of myocardium consisting of muscle cells were made for right and left ventricular free wall and septum in 127 hearts with normal coronary arteries. The hearts were normal (33 patients), had left ventricular hypertrophy (28 patients), right ventricular hypertrophy (25 patients), or chronic dilatation (41 patients). With cardiac enlargement, the average percent of myocardium consisting of muscle did not change from the approximately 75% value characteristic of normal hearts. In contrast, muscle cell nuclear density decreased proportionate to cardiac enlargement, demonstrating that muscle cell hypertrophy, not hyperplasia, is the basis for weight increase. Some hearts with marked longstanding dilatation also had perivascular and interstitital "striae" of connective tissue differing from replacement fibrosis. An increase in epicardial coronary artery caliber commensurate with increased heart weight suggests that ischemia is not the basis of connective tissue increase. The results show that cardiac muscle cell hypertrophy is accompanied by commensurate increase in interstitial connective tissues. This pattern of myocardial growth with cardiac enlargement may produce increased myocardial stiffness simply as a result of increased wall thickness, and may lead to left-sided congestive heart failure.
 ...
PMID:Constituents of the human ventricular myocardium: connective tissue hyperplasia accompanying muscular hypertrophy. 644 58

Isolated ischemic necrosis of the cecum is an infrequently described entity. We report three cases seen at our institution within a three-year period. All three patients had been hospitalized for congestive heart failure in the past, but none was in failure at the time of the most recent hospitalization. All three patients presented with clinical and laboratory findings consistent with acute appendicitis. At surgery the cecum was ischemic in each case, while the appendix and the remainder of the intestine appeared normal. There was no evidence of major vascular occlusion or embolization at the time of original operation. We propose that the cecum, like the splenic flexure, is a "watershed area," with poor blood supply relative to that of the adjacent intestine. While cecal ischemia has been described in association with a variety of clinical entities, we propose a newly recognized association with poor myocardial function. In such patients, isolated ischemic necrosis of the cecum should be considered in the differential diagnosis of right lower quadrant pain.
 ...
PMID:Isolated ischemic necrosis of the cecum in patients with chronic heart disease. 646 94

Thirty-four patients (26 men and 8 women) underwent myocardial revascularization following myocardial infarction (MI) at the Johns Hopkins Hospital during 1980 through 1982. Average age was 59 years. Of the 33 patients with unstable angina, 61% had ischemia in the infarct zone and 39% had "ischemia at a distance." Mean time from MI to operation was 16 days. The MIs were equally divided between a transmural and a subendocardial location. Eleven patients had a history of congestive heart failure. Intraaortic balloon pumping was used preoperatively for anginal stabilization in 14 patients. Mean ejection fraction for the group was 52%. There were 3 operative deaths, all 3 due to myocardial failure. Late follow-up (mean, 13.7 months; range, 6 to 35 months) is complete for 28 patients. There was 1 late death, secondary to cardiac failure. There were no late MIs. Angina had recurred in 5 patients, but only 2 were taking antianginal medication. At the time of follow-up, 52% of patients were in New York Heart Association Functional Class I. This experience suggests that operative intervention for postinfarction angina can be accomplished with an acceptable mortality and thereby increase survival, reduce the later occurrence of MI, and relieve angina in this high-risk group.
 ...
PMID:Operative intervention for postinfarction angina. 647 49

Localized obstruction in a suprarenal aorta of normal diameter is rare. Between 1970 and 1983, nine patients (all women, mean age 51 years) required aortic reconstruction to relieve severe lower extremity ischemia (nine patients), hypertension (nine), visceral ischemia (two), and congestive heart failure (three) caused by an eccentric, heavily calcified polypoid lesion originating from the posterior surface of the suprarenal aorta. This mass typically began at the level of the diaphragm and extended to the level of the renal arteries, almost totally occluding the aortic lumen. The rock-hard, irregular, gritty, whitish surface strongly resembled a coral reef. Elective revascularization was carried out in eight patients, and an emergency procedure was necessary in one patient who had acute aortic thrombosis with catastrophic visceral, renal, and lower extremity ischemia. The suprarenal atheroma was removed en bloc through a retroperitoneal thoracoabdominal aortic endarterectomy. Concomitant aortoiliofemoral revascularization was necessary in seven patients (five prosthetic grafts, two endarterectomies). Two patients died postoperatively. The seven long-term survivors remain asymptomatic at a mean follow-up interval of 4 years after revascularization, without evidence of recurrence of this lesion. Suprarenal "coral reef" atherosclerosis should be considered if visceral, renal, and limb ischemia is not adequately explained by the arteriographic pattern of conventional atherosclerosis. This unusual atheroma exhibited extensive calcification and metaplastic bone formation, although its precise pathophysiology remains to be defined.
 ...
PMID:"Coral reef" atherosclerosis of the suprarenal aorta: a unique clinical entity. 649 13

Coronary blood flow and myocardial energetics were assessed after the administration of a parenteral inotrope (dobutamine hydrochloride) and an oral vasodilator agent (hydralazine) in 10 patients with nonischemic congestive heart failure. Dobutamine (5 micrograms/kg per min) and hydralazine (1 mg/kg) when group-matched elicited an identical increase in cardiac index and stroke volume index. Both agents augmented coronary blood flow while reducing coronary vascular resistance. Both forms of therapy elicited a significant increase in myocardial oxygen consumption. Dobutamine, demonstrating a balanced effect on the coronary circulation, induced a proportional increase in coronary blood flow and myocardial oxygen consumption, with the arterial-venous oxygen difference across the coronary vascular bed remaining unchanged. Hydralazine enhanced the myocardial oxygen supply versus demand ratio; despite a significant increase in myocardial oxygen consumption, the arterial-venous oxygen difference and the myocardial extraction ratio diminished. Both forms of therapy enhanced cardiac performance without inducing any electrocardiographic or clinical evidence of ischemia. Dobutamine, a positive inotropic agent, elicited a balanced effect on the coronary circulation while hydralazine, a vasodilator agent, induced a greater increase in coronary flow than in myocardial oxygen demand.
 ...
PMID:Dobutamine and hydralazine: comparative influences of positive inotropy and vasodilation on coronary blood flow and myocardial energetics in nonischemic congestive heart failure. 682 60

Clinically, the first line of treatment for patients experiencing potentially lethal arrhythmias includes antiarrhythmic medications and/or treatment of underlying causes such as ischemia or congestive heart failure. However, if the treatment is not successful in controlling the arrhythmia, the automatic implantable defibrillator is a viable alternative for the prevention of sudden death in these patients. The case report presents one example of how the automatic implantable defibrillator can supplement conventional medical therapy when success in suppressing recurrent arrhythmias cannot be obtained. This concept has been demonstrated in this 59-year-old woman who underwent several medication trials in an attempt to control her life-threatening arrhythmias.
 ...
PMID:Automatic implantable defibrillator for the patient with recurrent refractory malignant ventricular arrhythmias: case report. 692 50

Neonatal arterial thrombosis has become more common with the use of umbilical artery catheters; however, catheter-induced aortic thrombosis is rare. A review of the literature disclosed a 100% mortality from medically managed neonatal aortic thrombosis. Two cases of umbilical artery catheterinduced acute neonatal thrombosis were managed successfully by surgical thrombectomy. Severe lower extremity ischemia and hypertension with aortic occlusion developed in two neonates, and intractable congestive heart failure developed in one of the neonates. This seems to be the first documented report of successful surgical treatment of umbilical artery catheter-induced aortic thrombosis. Acute neonatal aortic occlusion should be considered a surgical emergency.
 ...
PMID:Aortic thrombosis after umbilical artery catheterization. 706 81


<< Previous 1 2 3 4 5 6 7 8 9 10