Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Verapamil remains the most widely used calcium antagonist for the treatment of cardiac arrhythmias. It is the most potent and effective drug for the acute treatment of paroxysmal supraventricular tachycardia particularly, circus movement tachycardia with or without pre-excitation. 2. As it is a powerful depressant of atrioventricular nodal conduction it reduces the ventricular rate in atrial flutter and fibrillation with reversion to sinus rhythm in a proportion of patients with these arrhythmias. Because verapamil does not increase airways resistance it can be used in patients with obstructive airways disease. The drug is also effective in supraventricular tachyarrhythmias following open-heart surgery and myocardial infarction. 3. It is not an effective drug against ventricular arrhythmias unless due to coronary artery spasm. The use of verapamil should be avoided in the presence of sick sinus node syndrome, clinical cardiac failure and treatment with other negative inotropic drugs.
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PMID:Verapamil in cardiac arrhythmias: an overview. 674 51

Verapamil hydrochloride, a prototype calcium antagonist, is now marketed in the United States for the acute treatment of supraventricular tachyarrhythmias and for chronic management of vasospastic and chronic stable angina. It inhibits the slow inward channel in in the heart and blocks calcium influx in smooth muscle. Its intrinsic negative inotropic action, which is apparent in isolated tissues, is offset in vivo by peripheral vasodilation. It has a mild, noncompetitive sympathetic antagonist effect; its most important electrophysiologic action is a depression of AV nodal conduction, accounting for its effect in supraventricular tachyarrhythmias. Its hemodynamic actions are characterized by a complex interplay of changes in preload, afterload, contractility, heart rate, and coronary blood flow. It does not depress cardiac function, except in severe heart failure. The drug has a mild dilator action on coronary arteries and reverses ergonovine-induced vasoconstriction. Controlled trials have established its role in Prinzmetal's variant angina, unstable angina, and chronic stable angina. It has also been found to be effective in obstructive cardiomyopathies. The potential role of verapamil in such conditions as hypertension, cardioprotection, and Raynaud's phenomenon needs further evaluation; at present these indications have not been approved by the Food and Drug Administration. The most common side effects include constipation, skin rash, and dizziness; AV block, heart failure, and sinus arrest may occasionally be encountered, especially when ventricular function is compromised or conduction system disease is present.
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PMID:Verapamil hydrochloride: pharmacological properties and role in cardiovascular therapeutics. 676 30

Thirty-two volunteers with positive serologic tests for Chagas' disease were submitted to electrophysiologic studies. No one had documented tachyarrhythmias, heart failure, PR interval shorter than 0.12 or longer than 0.20 msec, pre-excitation or cardiac enlargement. The atrioventricular (AV) nodal function study under programmed atrial stimulation revealed abnormal AV nodal function in nine (28.1 percent) with long-term Chagas' disease. Due to the high incidence of the longitudinal dissociation in this disease, and based on previously reported histopathologic findings that demonstrate the involvement of the right side of the AV node and His bundle, this study suggests that the abnormal AV nodal responses may be secondary to the organic alterations produced by Chagas' disease.
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PMID:Abnormal atrioventricular nodal response patterns in patients with long-term Chagas' disease. 677 88

A retrospective study of 112 cases of lupus erythematosus, 103 acute disseminated lupus erythematosus (ADLE) and 9 chronic discoid lupus (CDL), was conducted to determine the incidence of disorders of conduction (DC), and to study their prognosis and discuss their pathogenicity. The mean age of the group was 38 +/- 16 years, and the mean follow-up period after discovery of the DC was 53 months. Cardiac lesions were present in 49.5 p. cent of the 103 patients with ADLE : pericarditis in 27 p. cent, murmur from lupus endocarditis or cardiomyopathy in 23 p. cent, heart failure in 4.8 p. cent, and hypertension in 17 p. cent. Disorders of conduction were present in 18 (17.5 p. cent) of the 112 patients studied. These included 5 partial right bundle-branch blocks (no complete right bundle-branch block), 2 complete and 3 partial left bundle-branch blocks, 5 complete, 2 first degree, and 1 second degree atrioventricular blocks (AVB). The atrioventricular blocks were usually located in the truncal or fascicular regions, but in 2 cases they were nodal in origin. The 5 complete AVB were associated with ADLE in two cases and CDL in the three other cases. The AVB in the ADLE cases appeared 9 to 20 years after the onset of the lupus, these two patients developing pericardiomyocarditis unaccompanied by disorders of conduction. The three complete AVB occurring during CDL were detected 9 to 18 months after the diagnosis. A fatal outcome was noted in 13 (12.5 p. cent) of the ADLE patients and one of the 9 cases of CDL. Ten-year survival curves showed no difference in prognosis for the groups with or without disorders of conduction, but mortality increased in patients with DC after 10 years. As disorders of conduction were more frequently observed in patients with lupus than in a control population, they can be attributed to either a lupus myocarditis or prolonged administration of synthetic antimalarial agents. Disorders of conduction, and particularly complete AVB are, in fact, observed in patients without pericardiomyocardial lesions, and when they exist usually develop a long time after the onset of the cardiac lesion. All patients had been treated with antimalarials, however, and the onset of the DC was associated with a chloroquine myopathy in some of them. Three of the five complete AVB were observed during the course of CDL in patients without cardiac lesions, this being a supplementary argument for implicating synthetic antimalarials.
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PMID:[Disorders of conduction in lupus erythematosus : frequency and incidence in a group of 112 patients (author's transl)]. 730 72

Sixty breast cancer patients with hormone-resistant metastatic disease who had progressed after chemotherapy with low-dose cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) or with L-phenylalanine mustard underwent treatment with a low-dose Adriamycin regimen,i.e., 20 mg/m2, intravenously on days 1 and 8 every 28 days. Two percent of patients had complete responses; 25%, partial responses; 38%, stabilization; and 35%, progression. The time to progression for the responders was similar to that of the stabilized patients, while the responders and stabilized patients survived significantly longer than did the progressors. Responses were seen in nodal, hepatic, dermal/subcutaneous, bone, pulmonary, and peritoneal metastases. The toxicity was mild: 18% of patients had leukocyte counts of less than 3,000/mm3; 10% had platelet counts of less than 90,000/mm3, 22% experience vomiting; and 33% had hair loss. No patient experienced local venous/subcutaneous toxicity or heart failure. Since this regimen of low-dose Adriamycin appears to be as effective as, but less toxic than, the secondary standard-dose of Adriamycin at 60--75 mg/m2 every three weeks, a randomized trial of low-dose Adriamycin vs. standard-dose Adriamycin should be conducted in metastatic breast cancer patients who have previously undergone chemotherapy.
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PMID:An effective low-dose adriamycin regimen as secondary chemotherapy for metastatic breast cancer patients. 739 18

Intravenous inotropic agents promote increased myocardial contractility via elevation of myocyte calcium concentrations, a mechanism that is also known to promote the development of cardiac arrhythmias. The purpose of this article is to review the electrophysiologic effects and relative potential for proarrhythmia associated with dobutamine, dopamine, and the phosphodiesterase inhibitors amrinone and milrinone. Dobutamine increases sinoatrial node automaticity and decreases atrial and atrioventricular (AV) node refractoriness and AV nodal conduction time. The drug also decreases ventricular refractoriness in both healthy and ischemic myocardium. Dobutamine has been shown to increase heart rate in a dose-related fashion in animals and in humans. In humans, dobutamine has been reported to induce ventricular ectopic activity (VEA) in 3% to 15% of patients, although VEAs are often asymptomatic, requiring no intervention. Ventricular tachycardia (VT) associated with dobutamine appears to occur rarely. Patients with underlying arrhythmias or heart failure or those receiving excessive doses of dobutamine are at greatest risk for proarrhythmia. Dopamine increases automaticity in Purkinje fibers and has a biphasic effect on action potential duration. Dopamine has been reported to induce atrial or ventricular arrhythmias in animals. In humans, dopamine may be associated with dose-related sinus tachycardia but has also been reported to cause VEA, which is usually asymptomatic. Dopamine-associated VT appears to occur rarely. Dopamine produces greater elevations in heart rate or frequency of ventricular premature beats at a given value of cardiac index than does dobutamine. The phosphodiesterase inhibitors amrinone and milrinone increase conduction through the AV node and decrease atrial refractoriness. Intravenous administration of these drugs may result in sinus tachycardia in some patients and has been reported to cause VEA, which is often asymptomatic, in up to 17% of patients. VT has also been reported in association with short-term use of intravenous phosphodiesterase inhibitors. In summary, intravenous inotropic agents may be associated with proarrhythmic effects in some patients. The primary arrhythmias reported are sinus tachycardia and VEA, although other supraventricular or ventricular arrhythmias have been reported less commonly. However, clinically significant proarrhythmic effects associated with these agents appear to occur rarely, and, at conventional doses, intravenous inotropic agents are relatively safe with respect to proarrhythmic effects.
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PMID:Electrophysiologic and proarrhythmic effects of intravenous inotropic agents. 756 5

The mechanisms, clinical presentation and therapy of supraventricular tachycardias are discussed. The therapy has changed from palliation by means of anti-arrhythmic drugs into definitive cure by ablation of the arrhythmia substrate. Radiofrequency energy causes tissue damage by heating and appears to be a safe method for catheter ablation of supraventricular tachycardias. We report a 97% success rate for radiofrequency ablation of 195 accessory atrioventricular pathways thereby curing these patients from circus-movement tachycardia and paroxysmal atrial fibrillation. Complications occurred in 3% of patients. One hundred seventy-two patients with atrioventricular nodal reentrant tachycardia, caused by reentry within dual AV-nodal pathways, were treated by selectively ablating one of the pathways with non-inducibility of the arrhythmia afterwards in 97% of the cases. Nine percent of patients had a recurrence but were successfully treated in a second session. The procedure was complicated by complete AV-block in 4% of patients. The disappointing medical treatment of atrial fibrillation and the fact that atrial fibrillation can be the cause of a reversible form of heart failure (tachycardiomyopathy), induced the clinical application of alternative forms of treatment. Ablation of the normal atrioventricular conduction system by using radiofrequency energy was performed with a 100% success rate in 121 patients. After implantation of a ventricular pacemaker it is possible to control and regulate the ventricular rhythm leading to rate control and amelioration of ventricular performance.
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PMID:New developments and treatment strategies in patients with supraventricular tachyarrhythmias. 759 73

The most important symptoms in bradycardia are vertigo, dizziness and syncopy due to diminished cerebral blood sypply. Cardial symptoms are cardiac insufficiency and angina pectoris. By means of ECG, especially Holter-ECG, carotid sinus massage, atropin test and invasive methods (atrial stimulation, His-bundle ECG) sinu-nodal dysfunction, carotid sinus syndrome, bradyarrhythmia absoluta and AV-block can be diagnosed. Pharmacological treatment is only useful in acute situations. For symptomatic bradyarrhythmias the implantation of a Pacemaker is the therapy of choice. Individual treatment of the various types of bradyarrhythmia and the patients special needs is possible through the evolution of pacemaker technology.
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PMID:[Differential diagnosis and therapy of bradycardic arrhythmias]. 782 27

This is the first documented case of spontaneous intermittent preexcitation associated with mesothelioma of the atrioventricular (AV) node. A 66-year-old male with recurrent atrial arrhythmias, palpitations, heart failure, and marked intra-atrial conduction defect that required a pacemaker died during sleep. Electrophysiologic study revealed left free-wall bypass tract with marked intra-atrial conduction defect and prolonged conduction across the bypass tract. With atrial pacing, high degrees of block were noted in the bypass tract. Serial section of the conduction system and both AV rims revealed two left posterior and lateral bypass pathways with patchy areas of fibrosis. A large mesothelioma (benign AV nodal tumor) almost completely replaced the AV node. In addition, there was marked fatty infiltration of the atria. In summary: (1) the intermittent preexcitation with prolonged conduction across the bypass tract and block with atrial pacing were probably related to the incomplete patchy degenerative changes in the bypass tract, and/or almost complete replacement of the AV node by the tumor; (2) the intra-atrial conduction defect was probably related to the replacement of the AV node by mesothelioma and/or the fatty infiltration of the atria; and (3) the paroxysmal atrial arrhythmias probably reflect the marked atrial pathology.
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PMID:Intermittent preexcitation and mesothelioma of the atrioventricular node: a hitherto undescribed entity. 854 78

In 1992, a 49-year-old woman was admitted to the hospital because of exertional dyspnea. Three years earlier sarcoidosis had been diagnosed, and the patient was found to have bilateral hilar lymphadenopathy. The eye, skin, and knee joint were also involved. During the second hospital stay, atrial flutter with advanced A-V nodal block, scattered defects on a 201T1 scintigram, and marked cardiomegaly on chest roentgenogram led to the diagnosis of cardiac sarcoidosis. Signs and symptoms of cardiac failure subsided after placement of an artificial cardiac pacemaker, but the patient still complained of mild muscle weakness in the lower extremities on exertion. 67Ga scintigraphy revealed marked accumulation in the lower extremities, and muscle biopsy of the left gastrocnemius revealed numerous epithelioid cell granulomas with muscle fiber degeneration. Oral corticosteroid therapy was effective. A review of the 24 cases of sarcoid myopathy reported in Japan indicated that the male-to-female ratio is 1:3.8. As compared to patients in whom myopathy led to the diagnosis of sarcoidosis, those in whom myopathy developed after sarcoidosis was diagnosed were (1) relatively older, (2) more likely to have multiple organ involvement, and (3) more likely to have cardiac sarcoidosis. Corticosteroids were beneficial in about three quarters of these 16 cases, who received corticosteroid therapy.
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PMID:[Cardiac sarcoidosis with myopathy and advanced A-V nodal block in a woman with a previous diagnosis of sarcoidosis]. 854 84


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