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)

5-Fluorouracil (5-FU) is widely used in the treatment of various solid tumors. However, 5-FU cardiotoxicity is being reported with increasing frequency. The main symptom of cardiotoxicity is chest pain at rest with ischemic electrocardiographic changes. Up until now, the underlying mechanism has been suspected to be coronary artery spasm. However, this chest pain associated with 5-FU has several characteristics that are incompatible with coronary artery spasm; eg, inefficacy of calcium-channel blocker and a slow increase in cardiac enzyme levels. We experienced a case of 5-FU-induced cardiotoxicity which showed clinical findings consistent with acute myocardial infarction. Based on the clinical findings, coronary angiography, and left ventricular angiography in a prolonged attack, we concluded that the cardiotoxicity in this case was not due to ischemia caused by coronary artery spasm.
 ...
PMID:A case of 5-fluorouracil cardiotoxicity simulating acute myocardial infarction. 759 36

A patient with tetanus showed marked ST segment elevation in ECG during fiberscope-guided nasotracheal intubation. Coronary artery spasm could have been induced probably by tetanospasmin and this would lead to transmural ischemia during procedure. Pretreatment with anti-hypertensive agents such as calcium antagonist as well as sedatives are mandatory even when endotracheal intubation without laryngoscope is scheduled in this disease.
 ...
PMID:[Marked ST segment elevation in ECG during fiberscope-guided nasotracheal intubation in a patient with tetanus]. 763 60

Patients with cardiac arrhythmias, ischemia, and infarction may benefit from administration of supplemental magnesium. However, the exact mechanisms for magnesium's beneficial effects remain unknown. Lysophosphatidyl choline (LPC), an amphipathic phospholipid released from cardiac cell membranes during ischemia, increases free intracellular calcium concentrations ([Ca]i) and has been implicated as a cause of cardiac arrhythmias and coronary artery spasm during myocardial ischemia. We postulated that magnesium acts by inhibiting cellular calcium overload induced by mediators such as LPC. Myocardial cells from male Sprague-Dawley rats were isolated from ventricular tissue samples and [Ca]i determined using the fluorescent dye, fura-2/acetoxymethyl ester, measured in a spectrofluorometer. The increase in [Ca]i after exposure to 100 and 200 microM LPC was recorded in cells suspended in modified Dulbecco's phosphate buffered saline solution with 0.2, 2.0, and 20 mM magnesium chloride. Differences were determined by analysis of variance with P < 0.05 considered significant. LPC significantly increased [Ca]i in the 100 microM (506 +/- 76 nM) and 200 microM (675 +/- 81 nM) concentrations, compared to baseline (301 +/- 25 nM). MgCl2 at both the 2.0 and 20 mM concentrations significantly blunted the increase in [Ca]i in myocardial cells exposed to LPC, whereas 0.2 mM MgCl2 was ineffective. LPC is a potent lipid mediator which increases myocyte [Ca]i in a concentration-dependent manner. Magnesium concentrations > or = 2.0 mM effectively antagonize the increase in [Ca]i induced by LPC. Thus, magnesium may limit intracellular calcium overload stimulated by ischemic-induced LPC release.
 ...
PMID:Magnesium antagonizes the actions of lysophosphatidyl choline (LPC) in myocardial cells: a possible mechanism for its antiarrhythmic effects. 776 33

We present three patients without significant coronary or other structural heart disease who were resuscitated after ventricular fibrillation attributed to coronary spasm. Angina pectoris was present in two of the cases and silent myocardial ischemia in the third. All patients were given calcium antagonists at discharge. A defibrillator was also implanted in the patient with silent myocardial ischemia because further episodes of ischemia would probably have occurred without premonitory symptoms. Coronary spasm might be a mechanism of ventricular fibrillation in patients without significant structural heart disease. Diagnostic tests should therefore be performed to confirm or exclude coronary spasm in such cases. The implantation of an automatic defibrillator seems justified in selected patients with documented coronary spasm, silent myocardial ischemia, and associated sustained ventricular tachyarrhythmia, although prospective studies are not yet available.
 ...
PMID:Ventricular fibrillation related to coronary spasm in patients without significant coronary or other structural heart disease. 804 79

This study was performed to assess the value of washout rate analysis of quantitative exercise thallium-201 emission computed tomography in vasospastic angina patients without significant coronary stenosis. Quantitative analysis of both thallium-201 perfusion and washout rate before and after drug treatment was performed in 48 patients with vasospastic angina and no significant coronary artery stenosis. All of the patients attained more than 90% of their age-predicted heart rate during each exercise test. Before drug treatment, 26 patients exhibited exercise-induced ischemia (perfusion defects on stress polar map), 17 did not exhibit exercise-induced ischemia (normal stress and washout rate polar maps), and the remaining 5 patients showed no perfusion defects, but did show extensive abnormal washout rates. On coronary angiography, multivessel coronary spasm was documented in 12 of the 26 patients with exercise-induced ischemia, in 7 of the 17 patients without exercise-induced ischemia and in 4 patients with an extensive abnormal washout rate and a normal stress polar map. In the 17 patients without exercise-induced ischemia, the mean washout rate was significantly decreased (p < 0.05) in association with a significant decrease in the double product (p < 0.05) after drug treatment. Of the 26 patients with exercise-induced ischemia, 18 (group 1) showed an increase in the mean washout rate with improved perfusion defect after drug treatment. The remaining 8 patients (group 2) showed a decrease in the mean washout rate with improved perfusion defect after drug treatment, which increased significantly on repeat exercise test performed after additional increased doses of antianginal drugs were administered (p < 0.01). The number of patients with multivessel coronary spasm was significantly high in group 2 (p < 0.01). Thirteen patients showed an extensive abnormal washout rate before drug treatment, including 8 patients with exercise-induced ischemia and 5 patients with no perfusion defects, who showed an increased mean washout rate after drug treatment (p < 0.05). These findings indicate that washout rate analysis aids in the diagnosis in vasospastic angina patients with exercise-induced ischemia. Some patients with exercise-induced ischemia can not be detected by thallium-201 perfusion analysis alone, especially those with multivessel coronary spasm and when this procedure is performed after drug treatment. In addition, a high frequency of abnormal washout rate in vasospastic angina may result not only from exercise-induced ischemia due to main epicardial coronary artery spasm, but also from microspasm, or impairment of microcirculation or myocyte.
 ...
PMID:Assessment of quantitative exercise thallium-201 emission computed tomography in patients with vasospastic angina--value of washout rate analysis. 806 9

Exercise and hyperventilation tests are often used as the provocative tests for coronary artery spasm. To examine the distribution of myocardial blood flow during exercise-induced and hyperventilation-induced attacks of coronary spasm, thallium-201 myocardial scintigraphy was performed in 47 patients with variant angina. The extent and severity scores and severity index (severity score/extent score) of scintigraphic perfusion defect were calculated. In 32 patients, anginal attack associated with ST elevation on the electrocardiogram was induced by exercise; in 23 patients, the attack was induced by hyperventilation. In patients with either anterior or inferior wall ischemia, both the extent and severity scores and severity index in the scintigram were significantly greater in exercise-induced anginal attack than those in hyperventilation-induced attack. In patients with simultaneous anterior and inferior wall ischemia, they tended to be greater in exercise-induced attack. In eight patients in whom anginal attack was induced by both exercise and hyperventilation, these scores and index were significantly greater in exercise-induced attack than those in hyperventilation-induced attack. These data suggest that myocardial ischemia during exercise-induced attack is enhanced as compared with that during hyperventilation-induced attack. Thallium-201 scintigraphy combined with exercise testing seems to be more sensitive for detecting myocardial ischemia induced by coronary spasm.
 ...
PMID:Comparison of the distribution of myocardial blood flow between exercise-induced and hyperventilation-induced attacks of coronary spasm: a study with thallium-201 myocardial scintigraphy. 819 71

This study examined the question of whether intracoronary administration of nitroglycerin modifies contralateral intracoronary acetylcholine test results. Acetylcholine was injected separately into both left and right coronary arteries in 63 patients with coronary spastic angina. Acetylcholine (20 and 50 micrograms) was injected first into the coronary artery responsible for the documented regional ischemia during spontaneous or induced attacks, and then into the other coronary artery. Coronary spasm was defined as severe transient coronary artery vasoconstriction with chest pain and/or electrocardiographic ischemic ST-segment deviation. Spasm was induced in either coronary artery in 60 patients (95%) and in both coronary arteries in 23 patients (37%). The frequency of induced spasm was 67% (42 of 63) in the coronary artery first challenged by acetylcholine. The coronary artery spasm subsided with the intracoronary injection of nitroglycerin (250-750 micrograms) in 19 patients. In the second challenge of intracoronary acetylcholine injection into the contralateral coronary artery, coronary spasm was induced in 29 (66%) of 44 patients. This was done without intracoronary administration of nitroglycerin in the first challenge and in 12 (63%) of 19 patients who had been given intracoronary nitroglycerin. The sensitivity for spasm induced by intracoronary acetylcholine appeared to be unaffected by nitroglycerin. Coronary spasm with ST-segment elevation by intracoronary acetylcholine in the second challenge was significantly less frequent in the patients receiving intracoronary acetylcholine in the second challenge was significantly less frequent in the patients receiving intracoronary nitroglycerin (first: 89%, second: 26%, p < 0.05) as well as in those not receiving intracoronary nitroglycerin for the spasm in the first challenge (first: 52%, second: 13%, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Effects of intracoronary administration of nitroglycerin on contralateral intracoronary acetylcholine test results. 844 91

We report a case of myocardial ischemia induced by cocaine. The ischemia probably induced by coronary artery spasm was reversed by nitroglycerin and calcium blocking agents.
 ...
PMID:Cocaine induced myocardial ischemia. 851 Dec 51

Toxic manifestations of digitalis are one of the most prevalent adverse drug reactions encountered in clinical practice. The estimated incidence is about 20% in hospitalized patients in the USA. The authors describe a rare case of myocardial "catecholamine necrosis" (anteroseptal myocardial infarction) during accidental digitalis intoxication. A male patient, 75 years old, suffering from cirrhosis and ascites, take on by mistake a tablet of digoxin 0.25 mg. four times at day for eleven days. He hadn't heart disease in the past. At the eleventh day the patient showed a deep tiredness and so he was submitted to a clinical examination and electrocardiogram. The ECG demonstrated an anteroseptal myocardial infarction in the second-third electrical stage. The patient was hospitalized. The successive examination revealed: very high plasma digitalis concentrations; an increase of the serum levels of CPK and LDH; a significant increase of plasmatic and urinary catecholamine levels which return to normal values after fifteen days; apical akinesia at the echocardiographic examination; no signs of residual myocardial ischemia to the echo-dypiridamole stress test; normal coronary artery to the coronary arteriography and absence of coronary artery spasm to the ergonovine test. Furthermore the abdominal echography and the abdominal computerized tomography didn't reveal surrenal disease but showed an important liver disease. The patient was free from other cardiac events in the follow-up. Generally, during the digitalis intoxication we observe various rhythm and conduction disturbances. Instead in this case no serious arrhythmias were registered and the main expression of the drug toxicity was an anteroseptal myocardial infarction with undamaged coronary artery. Also the usual extracardiac symptoms and signs of the digitalis intoxication were absent in this case. All these observations can be explained with the pathological increase of the cathecholamine levels, indirectly induced by digitalis; with the direct toxic effect of the drug at the myocardic level; with the contemporary absence of ionic disturbances; with the concomitant liver disease. The direct toxic effect of the digitalis produced an increase in calcium ions availability for the electromechanical coupling and an increase of the intramyocardial pressure; the increase of the adrenergic activity determined contemporary an increase in the oxygen consumption of the myocardial cells, a rise of vascular tone and coronary artery tone and a reduction of the duration of the diastole. All these factors provoked a "primary and secondary" ischemia which evolved toward a real "cathecholamine necrosis" and produced a myocardial infarction. This hypothesis explains the myocardial infarction in absence of injury at the coronary arteriography and without coronary spasm at the ergonovine test; moreover it explains the transient increase in cathecholamine plasma levels observed in the acute phases an normalized after fifteen days. The "cathecholamine necrosis" is an anatomical definition, nevertheless in our opinion it gives account of the rare clinical situation observed.
 ...
PMID:[An unusual case of "catecholamine necrosis" caused by accidental digitalis poisoning]. 855 67

The purpose of this study is to determine whether left ventricular dysfunction following coronary artery spasm by 123I-BMIPP myocardial imaging. To reveal the clinical efficacy of 123I-BMIPP SPECT, 20 patients with vasospastic angina were studied using resting, 3-hour delayed image with 123I-BMIPP and exercise, 3-hour delayed image with 201Tl SPECT. 123I-BMIPP uptake was decreased compared to 201Tl (discordant) in 12 patients (60%) and in 49/100 myocardial segments (49%). The extent and severity score in resting image with 123I-BMIPP were significantly larger than that in delayed image with 201Tl (p < 0.01). In 123I-BMIPP SPECT, the severity score in the latest ischemia were significantly larger than that in others. The incidence of a complete agreement of decreased 123I-BMIPP uptake and coronary artery spasm was significantly higher (75%) than that in 201Tl (28%, p < 0.01). Furthermore, compared to 201Tl uptake, decreased 123I-BMIPP uptake much more corresponded to reduced wall motion in 9 of patients with mismatching. The severity of regional wall motion abnormality was significantly correlated with severity score of 123I-BMIPP. Late redistribution in delayed image with 123I-BMIPP was seen in 6 patients. The regional washout rate and the severity of regional wall motion abnormality in 6 patients was significantly lower than that in others (p < 0.05). Thus, metabolic abnormality assessed by 123I-BMIPP is well associated with left ventricular asynergy and spastic region in patients with vasospastic angina. In conclusion, 123I-BMIPP SPECT may sensitively delineate the impaired myocardium following coronary artery spasm, and it is very useful in diagnosing and estimating the severity of vasospastic angina.
 ...
PMID:[Evaluation of myocardial damage using 123I-BMIPP imaging in patients with vasospastic angina]. 874 4


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