[Variant angina in peroral treatment with 5-fluorouracil].
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
To determine if the clinical features of variant angina are predictive of the severity of underlying coronary artery disease, 43 patients with variant angina who had less than 50% fixed coronary luminal diameter narrowing (group 1) were compared with 65 patients with variant angina who had 70% or greater diameter narrowing (group 2). Statistically significant differences were found in 3 clinical features between group 1 and group 2: (1) a more than 3-month history of angina at rest before diagnosis (80% vs 23%, p less than 0.001); (2) an abnormal electrocardiogram at rest (19 vs 48%, p less than 0.01); and (3) an abnormal stress test (26% [8 of 30] vs 84% [15 of 18], p less than 0.01). However, these features were not clinically reliable in separating patients with variant angina with and without fixed severe obstructions because of overlap between the 2 groups. No difference was found between the 2 groups in age, sex, predominant symptom at the time of catheterization, history of exertional angina, syncope with angina, prolonged angina, previous myocardial infarction or risk factors for coronary artery disease. There was also no difference in the location of ST elevation or occurrence of major arrhythmias during angina. Thus, among patients with Prinzmetal's variant angina, those with normal or mildly abnormal coronary arteriograms cannot be differentiated reliably by clinical features from those with fixed severe coronary obstructions. Coronary arteriography should be performed to define the underlying coronary anatomy and to determine optimal therapy in patients with variant angina.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
As discussed in part 1 of this article (page 97), intravenous verapamil (Calan, Isoptin) has established antiarrhythmic value. Attention now centers, however, on the antianginal value of the calcium channel blocking drugs because of the recent introduction of oral preparations for control of variant, stable and unstable angina.
A patient with severe variant angina that was refractory to conventional treatment became symptom free when she was treated with benzhexol (trihexyphenidyl hydrochloride), a cholinergic blocking agent used in the management of Parkinson's disease. There was a brief psychotic reaction when a large dose was taken and some memory impairment on the maintenance dose. Benzhexol should be used with caution but may prove to be an additional therapeutic agent in the management of severe variant angina.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The pharmacokinetics, clinical efficacy, and adverse effects of three calcium-channel blocking agents--verapamil, nifedipine, and diltiazem--are reviewed. Verapamil, nifedipine, and diltiazem are absorbed well after oral dosing, but absolute bioavailability of each is reduced substantially by a first-pass effect. Each drug is metabolized extensively (verapamil and diltiazem to moderately active metabolites) by the liver. A substantial percentage of each drug is bound to plasma proteins, but the binding is of clinical importance only for nifedipine (92--98% protein bound). Intravenous verapamil has become the agent of first choice for treatment of acute paroxysmal supraventricular tachycardia (PSVT); use of chronic oral verapamil therapy for prophylaxis remains controversial. Verapamil and diltiazem have been evaluated with mixed results for atrial flutter and fibrillation. For treatment of myocardial ischemia, calcium-channel blockers may be of some value (possibly in combination with nitrates of B blockers). All three agents have been studied in patients with exertional angina with good results. Calcium-channel blockers appear to be equal with nitrates for treatment of variant angina. Patients with hypertropic cardiomyopathy have been treated with verapamil and nifedipine with promising results. Nifedipine has been effective for treatment of essential hypertension. Adverse effects of calcium-channel blockers have been relatively minor or infrequent. Diltiazem overall has the best side-effect profile, with adverse effects causing discontinuation of therapy in about 2--10% of patients; verapamil in intermediate (8--10%) and nifedipine the worst (17%) in this respect. The most common side effects generally are fatigue, headache, dizziness, skin rash, and peripheral edema. While they generally should be reserved for patients in whom more conventional therapy has failed (except those with PSVT), calcium-channel blockers appear to have a valid role as reserve agents for exertional and variant angina, cardiomyopathy, and hypertension.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
We have previously reported that platelets of patients with variant angina exhibited pronounced hyperactivity to epinephrine, as assessed by aggregation study. To determine whether this is associated with a change in surface alpha-adrenoceptor status, we investigated the capacity and affinity of binding sites for [3H]dihydroergocryptine, a potent alpha-antagonist, of platelet lysates prepared from 22 patients with ischemic heart disease and 13 control subjects of similar age. [3H]DHE binding capacity to platelets from control subjects, 6 patients with acute myocardial infarction, 9 with effort angina and 7 with variant angina were 233 +/- 44 (SD), 226 +/- 53, 252 +/- 58 and 348 +/- 48 fmol/mg protein and its affinity were 2.05 +/- 1.40, 0.98 +/- 0.46, 1.59 +/- 0.37 and 1.49 +/- 0.66 nM, respectively. The patients with variant angina had significantly higher capacity of platelet alpha-adrenoceptor than controls (49% increase) or patients with other types of ischemic heart disease. In contrast, the affinity for [3H]DHE was not significantly different as compared with other three groups. Similar increments in the binding capacity for [3H]-rauwolscine, alpha 2 antagonist, were found in platelet lysates prepared from 6 patients with variant angina. These results suggest that increased capacity of platelet alpha-adrenoceptor may explain enhanced reactivity to epinephrine in patients with variant angina.