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)

Great cardiac vein blood flow by thermodilution and great cardiac vein oxygen saturation were measured in 14 patients with stable exertional angina and an angiographic pattern of complete occlusion of the proximal left anterior descending artery retrogradely filled by collateral vessels supplying still viable myocardium. Measurements were obtained under control conditions, at peak atrial pacing and after dipyridamole administration (0.56 mg/kg intravenously over 4 minutes). Both stress tests induced ischemic electrocardiographic changes in all patients, but dipyridamole administration resulted in greater ST-segment depression in 11 patients (1.6 +/- 0.5 vs 2.4 +/- 1.6 mm, p less than 0.05) and transient ST-segment elevation in 3 patients. Dipyridamole provoked ischemia at a lower value of rate-pressure product (145.3 +/- 30.6 vs 202.9 +/- 36.6 beats/min . mm Hg . 10(-2), p less than 0.0005) and anterior region myocardial oxygen consumption (9.32 +/- 4.76 vs 11.39 +/- 3.91 ml/min, p less than 0.05), despite a greater increase in great cardiac vein flow (139.4 +/- 45 vs 93 +/- 27.4 ml/min, p less than 0.0025) and a greater decrease in the calculated index of anterior region coronary resistance (0.87 +/- 0.27 vs 1.46 +/- 0.43 mm Hg/ml/min, p less than 0.0005). Moreover, great cardiac vein oxygen saturation increased more significantly during dipyridamole-induced ischemia than at peak pacing (63 +/- 12 vs 35 +/- 8%, p less than 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of atrial pacing and dipyridamole administration on coronary hemodynamics of collateralized myocardial regions in stable angina pectoris. 231 50

Although there have been anecdotal reports of cardiac toxicity associated with fluorouracil (5-FU) therapy, this phenomenon has not been studied in a systematic fashion. We prospectively performed continuous ambulatory ECG monitoring on 25 patients undergoing 5-FU infusion for treatment of solid tumors in order to assess the incidence of ischemic ST changes. Patients were monitored for 23 +/- 4 hours before 5-FU infusion, and 98 +/- 9 hours during 5-FU infusion. Anginal episodes were rare: only one patient had angina (during 5-FU infusion). However, asymptomatic ST changes (greater than or equal to 1 mm ST deviation) were common: six of 25 patients (24%) had ST changes before 5-FU infusion v 17 (68%) during 5-FU infusion (P less than .002). The incidence of ischemic episodes per patient per hour was 0.05 +/- 0.02 prior to 5-FU infusion v 0.13 +/- 0.03 during 5-FU infusion (P less than .001); the duration of ECG changes was 0.6 +/- 0.3 minutes per patient per hour before 5-FU v 1.9 +/- 0.5 minutes per patient per hour during 5-FU (P less than .01). ECG changes were more common among patients with known coronary artery disease. There were two cases of sudden death, both of which occurred at the end of the chemotherapy course. We conclude that 5-FU infusion is associated with a significant increase in silent ST segment deviation suggestive of ischemia, particularly among patients with coronary artery disease. The mechanism and clinical significance of these ECG changes remain to be determined.
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PMID:Continuous ambulatory ECG monitoring during fluorouracil therapy: a prospective study. 246 60

To assess the indication for percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG), we studied 93 patients with angina pectoris but without myocardial infarction. All patients had significant stenosis (greater than 50%) in at least one coronary artery, including the left anterior descending artery. Fifty-eight patients received medical treatment (Group I), 12 had PTCA (Group II) and 23 had CABG (Group III). Findings of coronary angiography, treadmill exercise tests and dipyridamole perfusion scintigraphy as well as the frequency of cardiac events during follow-up were assessed in each group. 1. Coronary angiography revealed 1 vessel disease in 38% of the patients in Group I, 58% in Group II, and 13% in Group III; 2 vessel disease in 33%, 25% and 61%; and 3 vessel disease in 29%, 17% and 26%, respectively. 2. Exercise duration with the treadmill test was 4.7 min in Group I, 4.0 min in Group II and 3.7 min in Group III. ST depression (greater than or equal to 1 mm) was induced in 75%, 83% and 95%, respectively. Exercise duration improved from 4.0 to 6.0 min after PTCA and from 3.7 to 4.5 min after CABG. Exercise-induced ST depression also became less frequent; from 83% to 25% after PTCA and from 95% to 32% after CABG. Dipyridamole perfusion scintigraphy showed reversible defects in 86% of the patients in Group I and in all patients in Groups II and III. Reversible defects were observed in 17% of the patients after PTCA and in 21% after CABG. 3. During a mean follow-up period of 26 months, cardiac deaths occurred in one patient (2%) in Group I and 2 (7%) in Group III. Nonfatal cardiac events (myocardial infarction and unstable angina or those necessitating revascularization--late PTCA or CABG) were observed in 12 patients (21%) in Group I, 4 (24%) in Group II and 10 (36%) in Group III. Anginal attacks at least once weekly remained in 12% of the patients in Group I, 19% in Group II and 14% in Group III at the last follow-up. In conclusion, PTCA and CABG appear to be effective methods for improving ischemia and exercise tolerance. However, preventive PTCA and CABG may not be indicated in patients with mild angina, because the prognosis is also excellent in medically-treated patients with angina but without myocardial infarction or left main coronary artery disease.
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PMID:[Indication for coronary revascularization for angina pectoris: correlation with prognosis of medically-treated patients]. 248 27

To examine the effect of coronary angioplasty on myocardial perfusion and to examine anatomic correlates of dipyridamole-thallium images, we performed dipyridamole thallium scanning before and after 24 angioplasty procedures in 23 patients with clinical ischemia. Dipyridamole thallium tomography was performed 1 to 4 (mean +/- S.D. 1.5 +/- 0.9) days before and 1 to 25 (6.3 +/- 6.9) days after angioplasty. Coronary angioplasty was anatomically successful (less than 50% residual stenosis) in 23 of 24 patients. Before angioplasty, 3 of 24 scans were interpreted as normal, with no change in these patients following angioplasty. Prior to angioplasty, 19 scans showed redistribution. After successful coronary angioplasty in 18 of 19, 17 showed improvement in dipyridamole thallium scanning; one did not show improvement and later required repeat coronary dilatation. In one patient with failed angioplasty, images before and after angioplasty were unchanged. Nine scans showed "fixed" defects before angioplasty, with improvement in three of nine following angioplasty. Quantitative analysis of the dipyridamole thallium scans revealed significant improvement in uptake in the myocardial regions supplied by the successfully dilated artery (involved regions), but not in the remote (uninvolved) regions. We conclude that myocardial perfusion, as judged by dipyridamole thallium scanning, almost always improves following anatomically successful coronary angioplasty. "Fixed" defects may improve following angioplasty and presumably represent ischemia with incomplete redistribution, rather than infarction.
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PMID:Dipyridamole thallium-201 imaging pre- and post-coronary angioplasty for assessment of regional myocardial ischemia in humans. 252 53

To determine half-life and turnover of plasma adenosine, heparinized blood from healthy volunteers was incubated with radiolabeled adenosine in the physiological concentration range of 0.1-1 microM. Plasma levels of adenosine in vitro were 82 +/- 14 nM and were similar to those determined immediately after blood collection with a "stopping solution." Dipyridamole (83 microM) and erythro-9(2-hydroxynon-3yl)-adenine (EHNA) (8 microM) did not measurably alter basal adenosine levels but completely blocked the uptake of added adenosine. Inhibition of ecto-5'-nucleotidase with 100 microM alpha, beta-methyleneadenosine 5'-diphosphate (AOPCP) reduced plasma adenosine to 22 +/- 6 nM. For the determination of adenosine turnover, the decrease in specific radioactivity of added [3H]adenosine was measured using a dipyridamole-containing stopping solution. Without altering basal adenosine levels, the half-life was estimated to be 0.6 s. Similar experiments were carried out with washed erythrocytes or in the presence of AOPCP, yielding half-lives of 0.7 and 0.9 s, respectively. When the initial adenosine concentration was 1 microM, its specific activity decreased by only 11% within 5 s, whereas total plasma adenosine exponentially decreased with a half-life of 1.5 s. Venous plasma concentrations were measured after relief of a 3-min forearm ischemia. Changes in plasma adenosine did not correlate well with changes in blood flow but were augmented in the presence of dipyridamole.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Turnover of adenosine in plasma of human and dog blood. 253 28

This is the first reported large clinical trial of the antianginal and acute ischemic effectiveness and safety of dilevalol (the R, R-isomer of labetalol) in patients with chronic stable angina pectoris. This was a multicenter double blind fixed-dose parallel group placebo controlled trial. Patients with chronic stable angina and positive and reproducible exercise tests (+/- 20%) were included. If randomized, patients entered one of four fixed dose groups (twice a day placebo, 100 mgm, 200 mgm and 400 mgm bid for 2 weeks). Exercise testing was performed at 2 hours (peak) and 12 hours (trough) postdosing. This was followed by a 2-week once-a-day dosing regimen in which patients received the same total daily dose as the prior 2 weeks, with the full dose in the morning and a matched placebo in the evening. Exercise testing was performed at 2 hours (peak) and 24 hours (trough) postdosing. Anginal frequency and NTG consumption were significantly reduced, and equally so, by qd and bid regimens. The time of exercise to the onset of angina increased and the proportion of patients terminating exercise because of moderate angina decreased in a dose response fashion for both peak and trough tests and for both qd and bid regimens. There was also a dose related decrease in exercise induced ST segment depression and an increase in time to 1 mm ST depression. In 15 patients, 24-hour ambulatory monitoring also revealed a decrease in episodes of silent ischemia. No significant side effects related to the study drug occurred.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The efficacy and safety of dilevalol in patients with chronic stable angina pectoris. 257 29

Anginal threshold and cardiac metabolism during infusion of glucose, 350 mg/min, were compared with control values before, during, and after pacing in nine patients with coronary artery disease (CAD) and nine patients without coronary artery disease (non-CAD). Pacing induced no ischemia in non-CAD patients; in CAD patients, intolerable angina developed in less than 5 minutes. However, glucose infusion in the latter group increased the time to onset of angina (110 +/- 24 seconds before infusion versus 140 +/- 24 seconds following infusion) and decreased the extent of ST segment depression (1.8 +/- 0.3 mm before infusion versus 0.9 +/- 0.2 mm following infusion, p less than 0.01) following pacing. In all subjects, arterial levels and cardiac uptake of glucose rose by 100% (p less than 0.001) and those of free fatty acids fell by 50% (p less than 0.01). Arterial lactate and uptake of lactate by nonischemic myocardium increased by 30% (p less than 0.05). During pacing in CAD patients, this elevated uptake was outweighed by similar increases of lactate release from ischemic areas, leaving mean negative global exchanges unaltered. In CAD patients solely, rebuilding of cardiac glycogen after pacing was suggested from augmented citrate efflux in the control period but not during glucose infusion, suggesting a glycogen-sparing effect. Arterial concentrations and net cardiac fluxes of oxygen, glutamate, and alanine remained unaltered. In conclusion, beneficial effects of glucose during ischemia are associated with increased aerobic and anaerobic glycolysis, saving of glycogen, and decreased lipolysis.
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PMID:Antianginal and cardiac metabolic effects of low-dose glucose infusion during pacing in patients with and without coronary artery disease. 266 29

The effects of two nucleoside transport inhibitors, dipyridamole and soluflazine, on adenosine, inosine and oxypurine release from the normoxic and hypoxic/ischemic rat cerebral cortex have been studied. Dipyridamole (500 micrograms/kg) enhanced adenosine release during hypoxic/ischemic challenges in comparison with saline-injected controls. It decreased the hypoxia/ischemia-elicited releases of inosine, hypoxanthine and xanthine. Both basal and hypoxia/ischemia-elicited releases of uric acid were elevated. Soluflazine, administered topically or systemically, failed to enhance adenosine release and did not consistently alter the hypoxia/ischemia-evoked releases of inosine, hypoxanthine and xanthine. Basal release of uric acid was elevated. The failure of either drug to elevate the basal or hypoxia/ischemia-evoked releases of adenosine above predrug levels illustrates one of the problems which may be inherent in the use of bidirectional nucleoside transport inhibitors for the manipulation of adenosine levels in the cerebral interstitial fluid.
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PMID:Effects of two nucleoside transport inhibitors, dipyridamole and soluflazine, on purine release from the rat cerebral cortex. 272 Mar 83

The individual and combined predictive values of dipyridamole-thallium imaging and exercise testing were compared in a prospective study of 70 patients who had abdominal aortic aneurysms or aortoiliac occlusive disease that required surgical repair. All patients were evaluated clinically by the same cardiologist and had exercise stress testing and dipyridamole-thallium imaging before admission for surgery. Ten patients were excluded from the study because they had evidence of severe ischemia when tested (ST segment depression greater than 2 mm on exercise testing, severe multivessel disease on thallium imaging). The remaining 60 patients were operated on (abdominal aortic aneurysm repair, 40; aortobifemoral repair, 17; femorofemoral graft, 3). The test results were withheld from the surgeon, anesthetist, and cardiologist before surgery. A total of 22 patients experienced major cardiac complications postoperatively (acute pulmonary edema, 17; acute myocardial, infarction, 5; cardiac death, 2). Thallium imaging showed myocardial ischemia in 31/60 patients. Exercise testing was positive (greater than or equal to 1 mm ST segment depression) in 10/60 patients. Dipyridamole-thallium imaging with a high sensitivity and reasonable specificity is the initial test of choice. Exercise testing is a poor screening test because of its low sensitivity. The combination of the two tests gives the highest positive predictive value and the greatest likelihood ratio. Thus patients assessed initially and found to have positive thallium scan results may be further stratified by exercise testing.
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PMID:A comparison of dipyridamole-thallium imaging and exercise testing in the prediction of postoperative cardiac complications in patients requiring arterial reconstruction. 274 1

After finding that Fomitiporia Runctata Murr had been used to treat angina pectoris as a folk remedy, medical workers of Fujian Sanming Fongous Institute engaged in the separation and identification of flora, and made out sugar-coated tablets of GML. This article reports clinical observation of tablets of GML treating 270 cases of CHD. Among the control group, 31 cases were treated by Persantine, 20 cases by Huo Xin Dan, 30 cases by compound Salviae miltiorrhizae. Among 222 cases of angina pectoris, 80 cases acquired evident effect (36%), 98 cases acquired improvement (44%), 42 cases failed to respond to the treatment (19%) and 2 cases became worse (1%). Total effective cases were 178 and total effective rate was 80%. There were 250 cases who had ECG evaluation: 37 cases acquired evident effect (15%), 95 cases showed improvement (38%), 116 cases had no change (46%) and 2 cases became worse (1%). Total effective cases were 132 and total effective rate was 53%. There was no significant difference between the effect of tablets of GML and that of Persantine, Huo Xin Dan and compound Salviae miltiorrhizae. According to the clinical laboratory observation, there were many functions of GML, such as antimyocardial ischemia, regulating heart rate, antiectopic cardiac rhythm and improving cardiac function and disorder in hemorrheology. The authors also used GML to treat 90 cases of arrhythmia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[A clinical study of guan mai Le in the treatment of coronary heart disease]. 276 25


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