Vitamins, supplements, herbal medicines, and arrhythmias

Nutritional and herbal supplements may have harmful or beneficial effects on arrhythmias. Potential supplements that may have antiarrhythmic activity include omega-3 polyunsaturated fatty acids (N-3 PUFA), coenzyme Q10, and carnitine. Clinical studies show that N-3 PUFA or fish oil supplementation appears to reduce mortality and sudden death. Coenzyme Q10, used in treatment of heart failure, and carnitine and its derivatives may have beneficial effects on arrhythmias, although clinical studies have been limited. Antioxidant supplements may be beneficial, but large studies with vitamin E have been disappointing in that it does not reduce mortality. Correction of electrolyte disturbances has been long advised and magnesium supplementation has been beneficial in the treatment of torsades de pointes and in some studies after cardiac surgery. However, routine electrolyte supplementation with empiric potassium or magnesium in non-deficient patients has not been convincingly beneficial. Several herbal supplements have also been promoted to have antiarrhythmic activity. However, clinical studies are lacking to support routine use of these herbal medications. In addition, some herbal supplements may cause serious proarrhythmia, and many supplements significantly interact with warfarin and digoxin.     

Cardiovascular adverse effects of herbal medicines: a systematic review of the recent literature

Herbal medicines are popular but health care professionals often feel uncertain about their risks. This article summarizes recent evidence regarding the serious or potentially serious cardiovascular adverse effects of herbal medicines. Five electronic literature databases were searched. The evidence found was mostly anecdotal. Case reports and case series indicate that life-threatening adverse effects of herbal medicines occur. Potentially serious adverse effects are arrhythmias, arteritis, cardiac glycosides overdose, chest pain, congestive heart failure, hypertension, hypotension, myocardial infarction, over-anticoagulation, pericarditis and death. The problems relate to toxic herbal ingredients, adulteration and contamination of herbal medicinal products, and herb-drug interactions. Herbal medicines that have been implicated repeatedly include aconite, ephedra and licorice. Because of the anecdotal nature of the evidence, it is impossible to estimate the incidence of adverse effects. In conclusion, herbal medicinal products are regularly associated with serious cardiovascular adverse events but the size of this problem cannot be estimated at present. Vigilance and research seem to be the best way forward.     

How useful is traditional herbal medicine for pulmonary fibrosis?

IPF, despite considerable advances in clinical management and understanding of its complex pathophysiology, is still a fatal disease without effective treatment. Herbal medicine has been used for more than 5000 years and is the central component of medical practice in many parts of Asia. Not surprisingly, traditional and herbal medicine is also widely applied for treatment of IPF. This review describes the most important herbal medicines that are used for IPF treatment. The relevant experimental studies investigating potential mechanisms of these drugs are discussed. The best conducted clinical studies which have reported beneficial effects of some herbal medications in the management of IPF are also evaluated. Overall, there is considerable experimental support from preclinical studies for some of these herbal medicines, but the translation into clinical practice appears difficult. The clinical trials evaluating their anti-fibrotic potential are not fulfilling the standards expected from 'Western' medicines. Systematic clinical research in this field is still in its infancy, and as such, the routine use of traditional and herbal medicine cannot be recommended for patients suffering from IPF.     

A rare cause of drug-induced hepatitis in an immunocompromised patient and the role of glutathione

The Food and Drug Administration (FDA) has issued a warning on numerous herbal drugs, including many popular products at General Nutrition Centers (GNC), regarding unstudied hepatotoxicity. There have been recent reports of GNC products such as hydroxycut and herbalife, causing drug-induced hepatitis. Herbal medications are over-the-counter products and are not investigated thoroughly by the FDA. Given that the mostcommon outpatient laboratory abnormality is elevated liver transaminases, a sign of hepatocellular toxicity; it is not surprising that some of these products end up causing hepatic dysfunction, especially when taken in large volume. There are numerous herbal supplements that are hepatotoxic, however, these medications have a much more significant effect in human immunodeficiency virus (HIV)/ acquired immune deficiency syndrome patients, which is secondary to depleted glutathione. We present a rare case of drug induced hepatitis secondary to herbal medications used to treat HIV and elucidate the role of glutathione depletion in immunocompromised patients.     

Bradycardia, reversible panconduction defect and syncope following self-medication with a homeopathic medicine.

Alkaloid extracts from the plant Aconitum species have been used in various forms of herbal remedies predominantly as anti-inflammatory and analgesic agents. Many of these alkaloids are extremely potent cardiotoxins and documented cases of various arrhythmias with fatal outcomes have been reported. We report a case of self-medication with 'tincture of aconite' resulting in severe bradycardia, reversible panconduction defect evidenced by sinus inactivity, atrioventricular dissociation with idiojunctional rhythm and left bundle branch block pattern resulting in hypotension and syncope. Complete reversal of ECG findings with marked improvement in symptoms was noted within a few hours. Herbal medicines containing aconite alkaloids may result in severe cardiotoxicity, and strict regulatory measures are warranted to curb unsupervised use for therapeutic purposes.     

Herbal antitussives

The mechanisms of actions of cough medicines are not always known. The problem is exacerbated for herbal medicines, where the effectiveness of the plant or its phytochemicals have rarely been carefully evaluated. Moreover, the most active phytomedicinal constituent is difficult to identify, and the expense and difficulty of such studies discourages sponsors who may not be able to benefit by subsequent exclusive marketing of the herbal remedy. Most popular herbs used as cough medicines appear to be demulcents whose action is confined to the oropharynx. It is probable that the vast majority of allegedly effective herbal cough medicines act as non-specific emetic-expectorants. The proof of activity of even marketed herbal derivatives such as guaifenesin and codeine is difficult to obtain. It is therefore likely that herbal cough medications will never be shown to be more active than placebos. Nevertheless, these plant products will continue to be popular remedies for patients and their health care advisors.     

Herbal Medications in Endodontics and Its Application—A Review of Literature

Herbal products are gaining popularity in dental and medical practice nowadays due to their biocompatibility, higher antimicrobial activity, antioxidant and anti-inflammatory properties. Herbal medicine has experienced rapid growth in recent years due to its beneficial properties, ease of availability, and lack of side effects. As pathogenic bacteria become more resistant to antibiotics and chemotherapeutic agents, researchers are becoming more interested in alternative products and treatment choices for oral diseases. As a result, natural phytochemicals separated from plants and utilized in traditional medicine are suitable substitutes for synthetic chemicals. The aim of this review article is to list and understand several herbal alternatives that are currently accessible for use as efficient endodontic medicaments. The herbal products used in endodontics have several advantages, including safety, ease of use, increased storability, low cost, and a lack of microbial tolerance. However, preclinical and clinical testing and interactions with other materials and adverse effects are required for these herbal products.     

Arginine vasopressin as a target in the treatment of acute heart failure

Congestive heart failure (CHF) is one of the most common reasons for hospitalization in the United States. Despite multiple different beneficial medications for the treatment of chronic CHF, there are no therapies with a demonstrated mortality benefit in the treatment of acute decompensated heart failure. In fact, studies of inotropes used in this setting have demonstrated more harm than good. Arginine vasopressin has been shown to be up regulated in CHF. When bound to the V1a and/or V2 receptors, vasopressin causes vasoconstriction, left ventricular remodeling and free water reabsorption. Recently, two drugs have been approved for use that antagonize these receptors. Studies thus far have indicated that these medications, while effective at aquaresis (free water removal), are safe and not associated with increased morbidity such as renal failure and arrhythmias. Both conivaptan and tolvaptan have been approved for the treatment of euvolemic and hypervolemic hyponatremia. We review the results of these studies in patients with heart failure.     

The effects of medications on myocardial perfusion

Antianginal and lipid-lowering medications may modify the results of stress myocardial perfusion imaging. Several studies have shown the beneficial potential of these agents in suppressing myocardial ischemia in patients with known coronary artery disease. The effects of nitrates, calcium-channel blockers, beta-blockers, and statins on myocardial perfusion imaging are likely attributable to changes in myocardial blood flow and myocardial oxygen supply-demand ratio. This comprehensive review examines relevant experimental and clinical published data. Technical issues in image interpretation specific to myocardial perfusion imaging and implications of use of cardiac medications to results of myocardial perfusion imaging are discussed.     

Clinical relevance of long-term therapy with levodopa and orally active dopamine analogues in patients with chronic congestive heart failure

Summary Beneficial effects of long-term treatment with dopamine analogues in patients with congestive heart failure may result from their vasodilating properties, in particular from renal artery vasodilation. Oral application of levodopa results in increased dopamine plasma levels and can improve cardiac performance and renal function in patients with congestive heart failure. A daily levodopa dosage of at least 4 g appears to a prerequisite for long-term response to the drug. Because of frequent side effects including nausea, vomiting, and dyskinesia at this dosage, the clinical usefulness of levodopa seems to be limited to a minority of patients. Ventricular arrhythmias have been shown to increase significantly during long-term levodopa therapy, probably due to stimulation of myocardial beta receptors. Increased ventricular arrhythmias or significant central nervous side effects have not been observed after administration of ibopamine and fenoldopam, which are orally active analogues of dopamine. Both agents exhibit potent arterial vasodilating properties and have been shown to increase cardiac performance in patients with congestive heart failure after short-term administration. The long-term beneficial effects of ibopamine and fenoldopam in the treatment of congestive heart failure have not yet been clarified. However, available results are encouraging and warrant further clinical evaluation of these agents, as well as the development of new analogues of dopamine, in particular of potent vascular dopamine₁ agonists.     

New antiarrhythmic agents: amiodarone, aprindine, disopyramide, ethmozin, mexiletine, tocainide, verapamil.

The present status, clinical experience, side effects, clinical pharmacology and electrophysiologic actions of seven new antiarrhythmic agents are reviewed. The drugs selected for comment are amiodarone, aprindine, disopyramide, ethmozin, mexiletine, tocainide and verapamil. Each drug has been shown to have clinical efficacy in suppressing cardiac arrhythmias.     

Clinical efficacy, mechanisms of action, and adverse effects of complementary and alternative medicine therapies for asthma.

Complementary and Alternative Medicine (CAM) therapies such as herbal therapy, acupuncture, yoga, homeopathy, chiropractic medicine, and massage therapy, continue to gain popularity as modalities for the treatment of asthma. In the Chinese, Japanese, Korean, Indian, and Western cultures, herbal therapies appear to be commonly used for allergies. Although well-controlled scientific studies have not been performed on many of the Asian herbal therapies and some basic studies have been performed on various herbal components (active ingredients), more needs to be done to assess the composite effects of many herbal remedies. An important part of the assessment of CAM modalities is the therapeutic-toxicologic safety profile (risk-benefit ratio), and further research evaluating the clinical efficacy and mechanism of action of various CAM interventions for asthma is greatly needed. This paper focuses on clinical and laboratory research regarding various CAM therapies that have been used in the treatment of asthma. The references cited are confined to literature originally published or translated into English.     

Herbal Medicine in the United States: Review of Efficacy,Safety, and Regulation

Introduction  Herbal products have gained increasing popularity in the last decade, and are now used by approximately 20% of the population. Herbal products are complex mixtures of organic chemicals that may come from any raw or processed part of a plant, including leaves, stems, flowers, roots, and seeds. Under the current law, herbs are defined as dietary supplements, and manufacturers can therefore produce, sell, and market herbs without first demonstrating safety and efficacy, as is required for pharmaceutical drugs. Although herbs are often perceived as “natural” and therefore safe, many different side effects have been reported owing to active ingredients, contaminants, or interactions with drugs. Results  Unfortunately, there is limited scientific evidence to establish the safety and efficacy of most herbal products. Of the top 10 herbs, 5 (ginkgo, garlic, St. John’s wort, soy, and kava) have scientific evidence suggesting efficacy, but concerns over safety and a consideration of other medical therapies may temper the decision to use these products. Conclusions  Herbal products are not likely to become an important alternative to standard medical therapies unless there are changes to the regulation, standardization, and funding for research of these products.     

Pflanzliche Arzneimittel

Herbal medicines are popular. It is frequently assumed that they are effective and safe. Sound knowledge of existing, or lacking, data on the efficacy and safety is required for advice and for the decision whether or not to use a particular herbal drug. Cochrane reviews are available for some herbal remedies. Most of them indicate either insufficient knowledge or weak or lacking efficacy. Numerous studies on interactions, some of which are clinically significant, for St. John’s wort with conventional drugs are available. Overall, although knowledge about herbal drugs has grown in recent years, it is generally still unsatisfactory. The active recommendation to use an herbal drug is usually not advisable. However, a patient’s request for a licensed herbal drug may be acceptable if there is no conventional concomitant comedication that is known or expected to interact, no contra-indication, and no other (conventional) treatment with better, or better known, benefit–risk ratio.     

Cascara sagrada-induced intrahepatic cholestasis causing portal hypertension: case report and review of herbal hepatotoxicity

Herbal medicines are gaining widespread popularity. Much of the public believes that botanical herbs are both harmless and useful for the treatment of a variety of symptoms. This belief stands in contrast with the fact that many herbal therapies have been shown to be toxic. In the present case report, cascara sagrada (CS) has been associated with the development of cholestatic hepatitis, complicated by portal hypertension. CS is a mixture of ingredients, among which is anthracene glycoside--an herbal agent that previously has been associated with chronic hepatitis. The liver injury in the case herein reported is believed to be related to either anthracene glycoside or one of the other constituents of CS.     

Pediatric cardiac electrophysiology

Over the past year, many advances have been made in the management of cardiac arrhythmias in the pediatric patient. It has become evident that the new surgical procedures for congenital cardiac disease can result in arrhythmia-associated morbidity and mortality. New pharmacologic agents such as adenosine have been shown to be efficacious in treating supraventricular tachycardias, and other agents such as flecainide, beta-blockers, and amiodarone are also of significant value in young patients with acute and chronic arrhythmias. Along with advances in the use of pharmacologic agents, pacing catheter techniques for the diagnosis and treatment of cardiac arrhythmias have also significantly progressed. Transcatheter ablation is safe and effective in our patient population, and an understanding of various pacemaker modalities and the physiologic parameters for optimum use have been defined. This review outlines the advances in all modes of treatment of cardiac arrhythmias.