Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Viagra, an oral drug taken one hour prior to sexual activity, improves erectile function in the majority of men with erectile dysfunction who receive it. It is not an aphrodisiac and therefore will not work without sexual stimulation. The drug is absolutely contraindicated in patients on organic nitrates, as this combination can lead to severe drops in blood pressure. Patients with heart disease, suspected heart disease and risk factors for heart disease should discuss with their physicians the safety of resuming sexual activity. A cardiac work-up, including exercise treadmill testing, should be considered in appropriate patients.
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PMID:Viagra: what every physician should know. 978 22

Sildenafil citrate, an oral therapy for erectile dysfunction, is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5), the predominant isozyme metabolizing cGMP in the corpus cavernosum. Chemically, it is a compound of the pyrazolo-pyrimidinyl-methylpiperazine class. Sildenafil has no direct relaxant effect on human corpus cavernosum but enhances the relaxant effect of nitric oxide (NO) on the corpus cavernosum by inhibiting PDE5, which is responsible for degradation of cGMP in this tissue. When sexual stimulation causes local release of NO, inhibition of PDE5 by sildenafil increases concentrations of cGMP in the corpus cavernosum, causing smooth muscle relaxation and blood flow into the penis, resulting in an erection. Sildenafil at recommended doses has no effect in the absence of sexual stimulation. The drug is rapidly absorbed after oral administration, with absolute bioavailability of 40%. Its pharmacokinetics are dose proportional over the recommended dosage range. Maximum plasma concentrations are reached within 30 to 120 minutes after oral dosing in the fasting state. Sildenafil is cleared predominantly by the hepatic microsomal isoenzymes CYP3A4 (major route) and CYP2C9 (minor route). Clinical studies assessed the effect of sildenafil on the ability of men with erectile dysfunction to engage in sexual activity and, specifically, to achieve and maintain an erection sufficient for satisfactory sexual intercourse. Sildenafil was evaluated at doses of 25, 50, and 100 mg in randomized, double-masked, placebo-controlled clinical trials of up to 6 months' duration. The drug was administered to hundreds of patients aged 19 to 87 years having erectile dysfunction of various etiologies for a mean duration of 5 years. Sildenafil was associated with statistically significant improvement in erectile function compared with placebo. Adverse effects reported at a rate of >2% were headache, flushing, dyspepsia, nasal congestion, urinary tract infection, abnormal vision, diarrhea, dizziness, and rash. No cases of priapism were reported. The use of sildenafil is contraindicated in men who are taking organic nitrates, because of the potential for a precipitous decrease in blood pressure. Postmarketing reports and surveillance have revealed at least 39 deaths with sildenafil use in men having a history of heart disease, men taking nitrate medications, and men in poor physical health due to lack of exercise. Many of the men who experienced serious adverse effects or death had a variety of concomitant diseases and were taking multiple medications.
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PMID:Safety and efficacy of sildenafil citrate in the treatment of male erectile dysfunction. 991 1

BACKGROUND: The introduction of the drug sildenafil (Viagra; Pfizer, New York, NY) into the armamentarium for treatment of erectile dysfunction is a major advance. Many of the patients who will benefit from its use have cardiovascular disease. Erectile dysfunction and cardiovascular disease share common risk factors. Although the metabolic demands of sexual activity are modest and the associated risk for coronary events is low, the clinician caring for cardiac patients needs to be aware of the pharmacology and hemodynamic profile of sildenafil in those with heart disease who use cardioactive drugs. METHODS AND RESULTS: We reviewed the current literature relating to the pharmacology, hemodynamic profile, efficacy, safety, and clinical application of sildenafil in patients with cardiovascular disease. Sildenafil is highly effective in the treatment of erectile dysfunction. The overall incidence of cardiovascular adverse events is low and similar to placebo. Current postmarketing data do not suggest an increase in cardiovascular death in sildenafil users. The drug is contraindicated in those taking organic nitrates. It should be used with caution and on an individual basis in patients who have active coronary ischemia and heart failure with tenous blood pressure and volume status. CONCLUSIONS: When used with discretion, sildenafil is safe, effective, and has the potential to greatly enhance quality of life in the relatively large proportion of the population with heart disease.
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PMID:Viagra and Cardiovascular Disease. 1068 47

Viagra and in vitro fertilization (IVF) with intraovocyte injection of spermatozoa (ICSI) have revolutionized the treatments of impotence and male sterility. They are able to treat successfully most of the cases whatever is the cause of the problem. The andrologist is tempted to renounce to look for an etiological factor and to treat directly his patient. The risk is to miss a diagnosis such as genital tract obstruction, testicular cancer, gonadotropin deficiency, sperm autoimmunity, coital disorders, or reversible toxin exposures, which could benefit from a specific treatment. Moreover IVF can endanger the woman's health and genetic consequences must not be overlooked if ICSI is performed. Concerning impotence a diagnosis of prolactinoma, diabetes or ischemic cardiopathy must not be missed because Viagra can also have cardio-vascular side-effects. This article reviews some etiological factors responsible for male infertility or impotence. The importance of a global appraisal of the patient is underlined in order not to limit his role to the one of a sperm producer.
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PMID:[Do viagra and fertilization in vitro announce the end of etiologic treatments in andrology?]. 1084 22

Erectile dysfunction (ED) and depression are highly prevalent conditions and frequently occur concomitantly in predisposed individuals. Men with ED and depression are also likely to have other comorbid conditions, including diabetes, hypertension, and heart disease. Because ED is also a common adverse effect of some medications for these conditions, patients are frequently noncompliant with treatment. Sildenafil citrate (Viagra) is effective in treating ED of a broad range of etiologies, suggesting that it may be equally beneficial in patients with ED that is associated with depressive symptoms and in those with ED resulting from serotonergic reuptake inhibitor (SRI) antidepressant treatment. We review the results of 3 randomized, placebo-controlled trials and a retrospective analysis of data pooled from 10 clinical trials that examine the efficacy of sildenafil in treating ED associated with depression and as an adverse effect of SRI treatment. The results suggest that sildenafil is efficacious as a first-line treatment for ED in men with untreated minor depression, in men with ED that is refractory to successful SRI treatment of depression, and in those whose depression was successfully treated but who developed ED as a consequence of SRI treatment. Given the complex interrelations among ED, depression, and other comorbid conditions, the key to proper management is a comprehensive evaluation, including sexual function, and an accurate differential diagnosis.
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PMID:Depression, antidepressant therapies, and erectile dysfunction: clinical trials of sildenafil citrate (Viagra) in treated and untreated patients with depression. 1241 34

Pulmonary hypertension is characterised by a progressive increase in pulmonary vascular resistance and a poor prognosis. The exact underlying mechanisms are still poorly understood; however, it is hypothesised that pulmonary medial hypertrophy and endothelial dysfunction lead to impaired production of vasodilators such as nitric oxide (NO) and prostacyclin, and increased expression of vasoconstrictors such as endothelin-1. The current treatment modalities for pulmonary hypertension include conventional supportive therapies and more specific pharmacological therapies that are targeted at abnormalities of endothelial function. NO and phosphodiesterase type 5 (PDE5) inhibitors induce pulmonary vasodilation by increasing intracellular cyclic guanosine monophosphate (cGMP) concentrations. Sildenafil citrate is a highly selective inhibitor of PDE5. Investigations in animal models and recent clinical case reports with some studies in the paediatric population suggest that sildenafil may be a promising agent in treating pulmonary hypertension. The effect of sildenafil on pulmonary vasculature appears to be independent of the underlying cause, thereby providing a role in idiopathic pulmonary arterial hypertension (PAH), PAH associated with congenital heart disease, pulmonary hypertension secondary to lung disease or persistent pulmonary hypertension of the newborn. It may also be beneficial in postoperative pulmonary hypertension and in neonates who are difficult to wean from inhaled NO. It is easily administered and effective, and has minimal systemic adverse effects. Although the reported results in children with pulmonary hypertension are promising, it is an experimental drug and large-scale randomised controlled studies are required to validate the safety, efficacy and dosage in the paediatric population.
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PMID:Therapeutic applications of sildenafil citrate in the management of paediatric pulmonary hypertension. 1720 64

We sought to determine the efficacy of postoperative oral sildenafil therapy (OST) in pediatric patients with congenital heart disease (CHD). A retrospective review of 45 postoperative patients with CHD who received OST was performed. Patients were categorized into three groups according to clinical indications: (1) to stabilize pulmonary vascular reactivity after biventricular repair (group 1 [n = 15]), (2) to lower pulmonary vascular resistance after bidirectional cavopulmonary shunt (group 2 [n = 12]), and (3) to improve post-Fontan hemodynamics (group 3 [n = 18]). Thirty-four patients (34 of 45 [75.6%]) had received inhaled nitric oxide (iNO) while on OST. Mean pulmonary arterial pressure (mPAP), mean systemic blood pressure (mSBP), and peripheral oxygen saturation (SpO(2)) were recorded during the first 24 hours after the initiation of OST. In group 1, the baseline mPAP/mSBP ratio (0.60 +/- 0.17) decreased significantly after the second (0.46 +/- 0.14, p = 0.004) and fourth (0.50 +/- 0.18, p = 0.025) doses of OST. In group 2, baseline SpO(2) (71.0 +/- 12.3%) increased after the fourth dose (75.1 +/- 12.3%, p = 0.04) of OST, without significant changes in mPAP. In group 3, baseline mPAP (14.8 +/- 3.3 mmHg) decreased significantly after the first (13.9 +/- 2.8 mmHg, p = 0.025) and second (13.3 +/- 1.9 mmHg, p = 0.016) doses of OST, without changes in SpO(2). In thirty-one (31 of 34 [92%]) subjects, iNO was discontinued within a median of 2 days after the initiation of OST, without rebound phenomena. There were no OST-related complications. Sildenafil citrate can be used safely in postoperative pediatric patients with CHD. Benefits from OST may be manifested differently in various clinical settings.
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PMID:Postoperative use of oral sildenafil in pediatric patients with congenital heart disease. 2005 28