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

A 63-year-old man with chronic atrial fibrillation and heart failure had a biventricular pacing system implanted. The pulse generator was a standard DDDR pacemaker, using the atrial channel for the right ventricular lead and the ventricular channel for the left ventricular lead. During final adjustment of the pacing parameters, a pacemaker tachycardia triggered by T wave oversensing from the right ventricular lead was recorded.
 ...
PMID:Pacemaker-mediated tachycardia in a biventricular pacing system. 1181 2

Atrial fibrillation is a common arrhythmia in patients with heart failure. The presence of atrial fibrillation deteriorates cardiac function and increases the risk of thromboembolic events. The management of patients with atrial fibrillation in association with heart failure should consist of ventricular rate control, prevention of thromboembolic events, and conversion to normal sinus rhythm. Traditionally, digoxin has been widely used in patients with heart failure and atrial fibrillation; however, it does very little to restore sinus rhythm and requires the addition of another rate-limiting agent to control ventricular rate. The likelihood of successful cardioversion is dependent on the duration of heart failure and the degree of neurohormonal activation. The initiation of antiarrhythmic drug therapy in patients with heart failure should be guided by safety issues as well as consideration of potential benefits vs. risks associated with therapy. Amiodarone has been evaluated in numerous clinical trials and appears to be safe and effective when used in low dosage. Treatment with dofetilide is another option. Comparative studies with oral dofetilide vs. amiodarone are needed to evaluate their efficacy in restoration and maintenance of sinus rhythm in patients with heart failure. Such trials will clearly define the role of dofetilide in the treatment of atrial fibrillation. Routine prophylactic use of antiarrhythmic drug therapy for chronic atrial fibrillation in the setting of heart failure is not recommended due to a low efficacy rate and high proarrhythmic risk. Anticoagulation with warfarin and rate control remain the standard therapy. (c)2001 by CHF, Inc.
 ...
PMID:Atrial fibrillation in patients with heart failure: pharmacologic options. 1182 32

The presence of diabetes mellitus and other risk factors of atherosclerosis, such as obesity, smoking and hyperlipidemia, in hypertensive patients makes the prognosis worse. Authors compared the clinical findings in diabetic hypertensive patients with and without left ventricular hypertrophy, the presence of which was diagnosed and defined by echocardiography. The study is based on the analysis of hospital records of 115 hypertensive patients treated at our department during the period 1998-1999. Left ventricular hypertrophy (LVH) was defined by echocardiography as left ventricular mass index > 134 g/m2 in men and > 110 g/m2 in women. Left ventricular hypertrophy was found in 79 patients (mean age 64.6 ys) but not in 36 patients (mean age 63.3 ys). Both groups were matched as to age and sex, intensity and duration of hypertension and diabetes, obesity, smoking and hyperlipidemia. In LVH-positive patients, there was a statistically significant incidence of heart failure, mitral regurgitation and renal involvement and a more non-significant incidence of left ventricular diastolic dysfunction, myocardial infarction, chronic atrial fibrillation and stroke than in LVH-negative ones. Left ventricular hypertrophy usually complicates the course of hypertension. Authors recommend to investigate the presence of left ventricular hypertrophy in hypertensives as it carries a much more complicated course of the disease. (Tab. 5, Ref. 28.)
 ...
PMID:Relation of left ventricular hypertrophy to cardiovascular complications in diabetic hypertensives. 1188 69

The object of this article was to estimate the incidence rate of chronic atrial fibrillation (AF) in a general practice setting, to identify factors predisposing to its occurrence, and to describe treatment patterns in the year following the diagnosis. The method used was a population-based cohort study using the General Practice Research Database (GPRD) in the UK. We identified patients aged 40-89 years with a first ever recorded diagnosis of AF. The diagnosis was validated through a questionnaire sent to the general practitioners. A nested case-control analysis was performed to assess risk factors for AF using 1,035 confirmed incident cases of chronic AF and a random sample of 5,000 controls from the original source population. The incidence rate of chronic AF was 1.7 per 1,000 person-years, and increased markedly with age. The age adjusted rate ratio among males was 1.4 (95% CI 1.2-1.6). The major risk factors were age, high BMI, excessive alcohol consumption, and prior cardiovascular comorbidity, in particular, valvular heart disease and heart failure. Digoxin was used in close to 70% of the patients, and close to 15% did not receive any antiarrhythmic treatment. Close to 40% did not receive either warfarin or aspirin in the 3 months period after the diagnosis. Among the potential candidates for anticoagulation only 22% of those aged 70 years or older were prescribed warfarin in comparison to 49% among patients aged 40-69 years. Chronic AF is a disease of the elderly, with women presenting a lower incidence rate than men specially in young age. Age, weight, excessive alcohol consumption, and cardiovascular morbidity were the main independent risk factors for AF. Less than half of patients with chronic AF and no contraindications for anticoagulation received warfarin within the first trimester after the diagnosis.
 ...
PMID:Incidence of chronic atrial fibrillation in general practice and its treatment pattern. 1192 3

Antiarrhythmic drugs in atrial fibrillation are relatively old and have well-specified indications. Class I antiarrhythmic drugs (IA: quinidine, disopyramide; IC: cibenzoline, flecainide, propafenone) are first indicated in patients without history of myocardial infarction and heart failure. In this last case, a b-blocker or amiodarone are indicated. Amiodarone is also indicated after failure of class I antiarrhythmic drugs. The association of class I antiarrhythmic drugs or amiodarone with a small dose of b-blocker is suitable if possible. However, the association of amiodarone with half-dose of a class I antiarrhythmic drug should remain rare, because the prognosis of chronic atrial fibrillation is unknown; the benefits to risks ratio of antiarrhythmic treatment should be discussed for each patient.
 ...
PMID:[Antiarrhythmic drugs in atrial fibrillation]. 1272 32

The L-type Ca2+ current (I(Ca-L)) plays a key role in the cardiac excitation-contraction (E-C) coupling. Thus, it is a major target for many transmitters and hormones modulating cardiac function and, therefore, for pharmacological drugs to regulate inotropy. Ca2+ (and other) ion currents are commonly studied in animal tissues for practical reasons. Investigations in human cardiomyocytes started extensively only ten years ago with the development of patch-clamp techniques, enzymatic cell dissociation procedures, and surgical techniques. These studies have already provided valuable information concerning the nature, biophysics, pharmacology and regulation of human cardiac ionic currents in normal and diseased tissues. Interesting advances have been made to understand the role of I(Ca-L) in the development of chronic atrial fibrillation (AF). Alterations of single channel activity and regulation of macroscopic I(Ca-L) have also been found in heart failure (HF), ugh some of the data are divergent and puzzling. The T-type Ca2+ current (I(Ca-T)) has never been recorded in human cardiomyocytes. After a rapid overview of the basic properties of human cardiac Ca2+ currents, we focus on selected aspects of pathophysiology that are still unsolved.
 ...
PMID:Voltage-gated Ca2+ currents in the human pathophysiologic heart: a review. 1247 28

The clinical relevance and high social costs of atrial fibrillation have boosted interest in rate control as a cost-effective alternative to long-term maintenance of sinus rhythm (i.e. rhythm control). Prospective studies show that rate control (coupled with thromboembolic prophylaxis) is a valuable treatment option for all forms of atrial fibrillation. The rationale for rate control is that high ventricular rates, frequently found in atrial fibrillation, lead to haemodynamic impairment, consisting of a variable combination of loss of atrial kick, irregularity in ventricular response and inappropriately rapid ventricular rate, depending on the type of underlying heart disease. Long-term persistence of tachycardia at a high ventricular rate can lead to various degrees of ventricular dysfunction and even to tachycardiomyopathy-related heart failure. Identification of this reversible and often concealed form of left ventricular dysfunction can permit effective management by rate (or rhythm) control. Although acute rate control (to reduce ventricular rate within hours) is still often based on digoxin administration, for patients without left ventricular dysfunction, calcium channel antagonists or beta-adrenoceptor antagonists (beta-blockers) are generally more appropriate and effective. In chronic atrial fibrillation, long-term rate control (to reduce morbidity/mortality and improve quality of life) must be adapted to patients' individual characteristics to grant control during daily activities, including exercise. According to current guidelines, the clinical target of rate control should be a ventricular rate below 80-90 bpm at rest. However, in many patients, assessment of the appropriateness of different drugs should include exercise testing and 24h-Holter monitoring, for which specific guidelines are needed. In practice, rate control is considered a valid alternative to rhythm control. Recent prospective trials (e.g. the Pharmacological Intervention in Atrial Fibrillation [PIAF] and the Atrial Fibrillation Follow-up Investigation of Rhythm Management [AFFIRM] trials) have shown that in selected patients, rate control provides similar benefits, more economically, in terms of quality of life and long-term mortality. The choice of a rate control medication (digoxin, beta-blockers, calcium channel antagonists or possibly amiodarone) or a non-pharmacological approach (mainly atrioventricular node ablation coupled with pacing) must currently be based on clinical assessment, which includes assessing the presence of underlying heart disease and haemodynamic impairment. Definite guidelines are required for each different subset of patients. Rate control is particularly tricky in patients with heart failure, for whom non-pharmacological options can also be considered. The preferred pharmacological options are beta-blockers for stabilised heart failure and digoxin for unstabilised forms.
 ...
PMID:Rate control in atrial fibrillation: choice of treatment and assessment of efficacy. 1283 66

Although atrial fibrillation is common in patients with heart failure, patients with atrial fibrillation are often excluded from congestive heart failure trials or are not analyzed separately. Consequently, while the effect of angiotensin-converting enzyme inhibitors in patients with sinus rhythm is well established, the effect on patients with atrial fibrillation is unknown. The authors hypothesized that these agents might be particularly effective in this patient category, given their antiadrenergic properties and the importance of adequate rate control. Therefore, the effects of lisinopril 10 mg once daily were evaluated in 30 patients with congestive heart failure and chronic atrial fibrillation (mean age, 68 +/- 6 years) in a double-blind, randomized, placebo-controlled trial. All patients were in New York Heart Association class II or III and were stable on conventional therapy (digoxin, diuretics, nitrates). After 6 weeks, mean peak oxygen consumption increased from 14.7 +/- 3.4 to 15.9 +/- 2.9 mL/min/kg in the lisinopril group (P = .034). Plasma norepinephrine levels during exercise and at peak exercise tended to be lower when the patients were taking lisinopril (10.8 +/- 4.2 to 8.9 +/- 4.4 nmol/L and 16.3 +/- 9.2 to 14.3 +/- 7.7 nmol/L, P < .1). Heart rate during exercise and ambulatory monitoring was not significantly affected. Left ventricular fractional shortening tended to increase after lisinopril (23 +/- 7 to 27 +/- 9%, P = .073). Left atrial volume was unchanged, as were plasma atrial natriuretic peptide levels. After subsequent electrical cardioversion, treatment was continued for 6 more weeks, allowing assessment of the effect of lisinopril on maintenance of sinus rhythm; maintenance of sinus rhythm was 71% in the lisinopril group and 36% in the placebo group (P = NS). This study shows that treatment with an angiotensin- converting enzyme inhibitor improves peak oxygen consumption in patients with congestive heart failure and chronic atrial fibrillation. Attenuation of adrenergic drive during exercise may play a role in mediating this effect.
 ...
PMID:Effects of lisinopril in patients with heart failure and chronic atrial fibrillation. 1283 10

Sustained or chronic tachyarrhythmia can produce reversible changes of atria or/and ventricles that induce systolic or/and diastolic disfunction, dilatation of heart chambers and progressive symptoms of heart failure. The changes regress after restoration of sinus rhythm. This is the clinical case, when at the beginning of the treatment, primary dilated cardiomyopathy is diagnosed to the patient having chronic atrial fibrillation and later after restoration of sinus rhythm and subsequent reduction of heart chambers as well as improvement of systolic function, past changes was assessed as reversible arrhythmogenic cardiomyopathy.
 ...
PMID:[Arrhythmogenic dilated cardiomyopathy]. 1287 22

Four recent randomized controlled studies that compared rhythm control versus rate control therapy demonstrated that rate control therapy is an acceptable alternative to rhythm control therapy. The control of heart rate achievable with pharmacologic therapy is imperfect and, in many patients, difficult to obtain. Ablation and pacing therapy offers better control of heart rate than drug therapy. The aim of the PAF 2 trial was to evaluate the effect of antiarrhythmic drug therapy on long-term maintenance of normal sinus rhythm after ablation and pacing therapy and to evaluate the effect of maintenance of normal sinus rhythm on major clinical events, quality of life and cardiac performance and, therefore, to evaluate whether antiarrhythmic drug strategy yields any additional benefit to ablation and pacing therapy. In this multicenter randomized controlled trial, 68 patients with severely symptomatic paroxysmal atrial fibrillation were assigned, after successful atrioventricular junction ablation and pacing treatment, to antiarrhythmic drug therapy with amiodarone, propafenone, flecainide or sotalol and were compared with 69 patients assigned, after successful AV junction ablation and pacing treatment, to no antiarrhythmic drug therapy. Although patients in the antiarrhythmic drug arm had a reduction in the risk of developing chronic atrial fibrillation, there was no clinical benefit beyond that obtained with ablation and pacing alone. On the contrary, antiarrhythmic therapy was associated with more serious adverse clinical events, i.e. episodes of heart failure and hospitalization. This suggests that the control of ventricular rhythm by ablation and pacing has a greater beneficial effect on short-term clinical outcome than the preservation of atrial contraction. Therefore, the results of PAF2 study are consistent with the drug trials comparing rhythm and rate control.
 ...
PMID:Rhythm versus rate control after ablation and pacing for paroxysmal atrial fibrillation: clinical implications of the PAF 2 trial. 1461 35


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