Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carbon monoxide poisoning causes tissue hypoxia because of reduced transfer and altered release of oxygen by hemoglobin. Considering many case histories, we realized that symptoms and clinical signs of acute poisoning are mostly neurologic: coma, headache, dizziness, vomiting. On the contrary, it seems that myocardium, the other organ which mostly requires O2, is attacked in a "silent way". ECG in 5 patients with accidental carbon monoxide poisoning underlined that cardiac rate increased (3 of them presented tachyarrhythmias by atrial fibrillation) and the presence of more or less important alteration of ventricular repolarization like "subendocardial lesion". Simple hyperbaric oxygen treatment determined the regression of the rhythm disorder and of the abnormalities of ventricular repolarization. The only patient who had not the restoration of sinus rhythm had chronic atrial fibrillation.
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PMID:[Cardiologic aspects of carbon monoxide poisoning]. 275 46

Carotid sinus hypersensitivity (CSH) has been studied in subjects in sinus rhythm, but it has never been studied in patients with chronic atrial fibrillation (AF). After a finding of CSH in a patient with chronic AF and syncope, we studied the effects of carotid sinus stimulation in a group of patients with AF. Ten patients with chronic AF and normal ventricular rates who complained of dizziness or loss of consciousness underwent right and left carotid sinus massage (CSM) during ECG monitoring. A control group of ten patients with AF but without neurological symptoms was likewise investigated. CSH was present in eight symptomatic patients (5 patients presented right CSH, 1 left and 2 bilateral CSH), but only in three of the control patients. The mean duration of asystole induced by right CSM was 5.94 +/- 2.10 seconds; the mean asystolic interval induced by left CSM lasted 8.58 +/- 1.42 seconds. Six patients in the symptomatic group had a recurrence of spontaneous symptomatology during CSM, so that a diagnosis of carotid sinus syndrome was established. All symptomatic patients (8 patients with CSH, 2 patients with ventricular standstills but without CSH) received a permanent ventricular pacemaker. Following pacing, all patients, except for one with a significant drop of systolic blood pressure during CSM, became completely asymptomatic. In elder patients with chronic AF, CSH can induce prolonged ventricular asystole, which may be responsible for neurological symptoms such as dizziness, presyncope, or syncope, as observed in patients in sinus rhythm with carotid sinus syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Carotid sinus hypersensitivity and syndrome in patients with chronic atrial fibrillation. 780 May 66

Patients with supraventricular arrhythmias have been safely and effectively treated with flecainide. We conducted an open-label, 20-center trial to define further the safety and efficacy profile of oral flecainide in patients with supraventricular arrhythmias, including atrial tachycardias (ectopic or multifocal), atrial-ventricular tachycardias (reentrant), paroxysmal atrial fibrillation/flutter (PAF), and chronic atrial fibrillation (CAF). Our study population of 151 patients with documented supraventricular arrhythmias requiring treatment included 67 with paroxysmal supraventricular tachycardia (PSVT), 67 with PAF (symptoms < 15 days), and 17 with CAF (symptoms > of = 15 days)> The initial flecainide dose of 100 mg twice daily could be increased by 50 mg bid every 4 days to a maximum of 200 mg twice daily. Patients who were effectively treated could receive flecainide for 1 year. The study was terminated April 26, 1989, in response to interim results reported by the Cardiac Arrhythmia Suppression Trial (CAST). All patients were removed from the study by August 1989. At study termination 87% of PSVT, 73% of PAF, and 56% of CAF patients had improved symptomatically while on flecainide therapy. Eleven patients experienced cardiac adverse experiences: proarrhythmic events (3 patients), new or worsened congestive heart failure (7 patients), sinus pauses (1 patient). Cardiac side effects appeared to be more frequent in patients in the CAF group (5/17 patients), all of whom had structural heart disease. Overall, 45 (67%) PSVT, 43 (64%) PAF, and 9 (56%) CAF patients reported at least 1 noncardiac adverse experience; the most common were abnormal vision, dizziness, and headaches. One patient from the CAF group died; the death was considered to be unrelated to flecainide. Flecainide appears to be safe and effective treatment for patients with supraventricular arrhythmias of a variety of mechanisms and appears particularly effective for patients with PSVT. The efficacy is lowest and side effects most frequent in patients with CAF, as seen with other trials of antiarrhythmic medication in these patients. In the context of the CAST experience and other trials of antiarrhythmic drugs in patients with CAF, the balance of risk and benefit of therapy should be considered carefully before initiating treatment.
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PMID:Safety and utility of flecainide acetate in the routine care of patients with supraventricular tachyarrhythmias: results of a multicenter trial. The Flecainide Supraventricular Tachycardia Study Group. 860 95

The efficacy and safety of intravenous propafenone for conversion of recent-onset and chronic atrial fibrillation was assessed in 46 patients. 40 with atrial fibrillation associated with or without structural heart disease (mean age 63 +/- 14 years) and 6 patients with atrial fibrillation related to the Wolff-Parkinson-White syndrome (mean age 34.8 +/- 13 years). Propafenone treatment was administered at 2 mg/kg over 15 minutes under continuous electrocardiographic monitoring. In 28 of 32 (87.5%) patients with paroxysmal and/or recent-onset atrial fibrillation a stable sinus rhythm was restored within 1 hour after propafenone (mean 17 +/- 11 minutes) and in only 3 of 8 (37.5%) with chronic atrial fibrillation (p < 0.05). Conversion to sinus rhythm was obtained in 5 of 6 (83.3%) patients with atrial fibrillation related ventricular preexcitation, mean time 21 +/- 12 minutes. Propafenone had an additional effect reducing mean heart rate (141 +/- 21 to 102 +/- 15 beat per minute, p < 0.05) and the shortest preexcited R-R intervals was increased, mean 231.6 +/- 27.8 to 355 +/- 37.2 milliseconds (p < 0.001) in cases associated with ventricular preexcitation. Dizziness, hypotension and transient conduction disturbances occurred in only one patient with rheumatic valvular heart disease: EF 40%. Propafenone is an effective and safe antiarrhythmic drug for converting paroxysmal and/or recent-onset atrial fibrillation of various origins with a more limited efficacy in chronic atrial fibrillation.
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PMID:[Pharmacological cardioversion with intravenous propafenone in atrial fibrillation]. 1093 1

Although atrial fibrillation is not widely known by the general public, in developed countries it is the most common arrhythmia. The incidence increases markedly with advancing age. Thus, with the growing proportion of elderly individuals, atrial fibrillation will come to represent a significant medical and socioeconomic problem. The consequences of atrial fibrillation have the greatest impact. The risk of thromboembolism is well known; other outcomes of atrial fibrillation are less well recognised, such as its relationship with dementia, depression and death. Such consequences are responsible for diminished quality of life and considerable economic cost. Atrial fibrillation is characterised by rapid and disorganised atrial activity, with a frequency between 300 and 600 beats/minute. The ventricles react irregularly, and may contract rapidly or slowly depending on the health of the conduction system. Clinical symptoms are varied, including palpitations, syncope, dizziness or embolic events. Atrial fibrillation may be paroxysmal, persistent or chronic, and a number of attacks are asymptomatic. Suspicion or confirmation of atrial fibrillation necessitates investigation and, as far as possible, appropriate treatment of underlying causes such as hypertension, diabetes mellitus, hypoxia, hyperthyroidism and congestive heart failure. In the evaluation of atrial fibrillation, cardiac exploration is invaluable, including electrocardiogram (ECG) and echocardiography, with the aim of detecting cardiac abnormalities and directing management. In elderly patients (arbitrarily defined as aged >75 years), the management of atrial fibrillation varies; it requires an individual approach, which largely depends on comorbid conditions, underlying cardiac disease, and patient and physician preferences. This management is essentially based on pharmacological treatment, but there are also nonpharmacological options. Two alternatives are possible: restoration and maintenance of sinus rhythm, or control of ventricular rate, leaving the atria in arrhythmia. Pharmacological options include antiarrhythmic drugs, such as class III agents, beta-blockers and class IC agents. These drugs have some adverse effects, and careful monitoring is necessary. The nonpharmacological approach to atrial fibrillation includes external or internal direct-current cardioversion and new methods, such as catheter ablation of specific foci, an evolving science that has been shown to be successful in a very select group of atrial fibrillation patients. Another serious challenge in the management of chronic atrial fibrillation in older individuals is the prevention of stroke, its primary outcome, by choosing an appropriate antithrombotic treatment (aspirin or warfarin). Several risk-stratification schemes have been validated and may be helpful to determine the best antithrombotic choice in individual patients.
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PMID:Atrial fibrillation in the elderly: facts and management. 1242 93

A 73-year old woman presented with mild paraparesis and hypesthesia of the legs. Furthermore, she complained dizziness, fainting and dyspnea. There was a history of peripheral artery disease, diabetes mellitus, arterial hypertension and chronic atrial fibrillation. Five years ago she had breast cancer with removal of the left mamma and additional radiation therapy. Cardiac catheterization at that time demonstrated no significant coronary stenoses. A contrast-enhanced CT-scan excluded lumbal spinal metastases. Instead, a subtotal occlusion of the abdominal aorta was noticed, but was initially interpreted as a chronic thrombosis because there were no typical symptoms and only moderate pain. About 24 hours later the patient developed an acute ischemic syndrome of the legs with progressive paraparesis, cold and pale legs in combination with acidosis and hyperventilation. Color-coded duplex ultrasound showed only a small turbulent flow in the ilial arteries, highly suspicious of a complete occlusion of the distal aorta. Angiography revealed an acute total occlusion of the infrarenal aorta without collaterals. During surgical intervention, complete obstruction of the abdominal aorta above the bifurcation was confirmed. Subsequent embolectomy was performed and an embolus consisting of several layers of different age was extracted. After successful surgical intervention with subsequent clinical improvement, the patient's clinical condition deteriorated a few day later. She died on day 9 after surgery from a complete ischemia of the small intestine and the colon ascendens.
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PMID:[Atypical Leriche syndrome]. 1265 74

The aim of the study was to assess the situation with implantation of cardiac pacemakers and to critically evaluate the possibility of this method of treatment. The study was conducted from 2001 to 2007. Data on a total of 211 operations were included in the study. There were 121 (57.3%) male patients, mean age 69.7 years, and 90 (42.7%) female patients, mean age 74.5 years. Total number of operations increased from 18 in 2001 to 24 in 2002, 28 in 2003, 38 in 2004, 38 in 2005, 30 in 2006 and 35 in 2007. Primo implantation was carried out in 196 (92.9%) cases. The following types of pacemakers were used: VVI in 79 (40.3%), VVIR in 73 (37.2%), DDD in 7 (3.6%), DDDR in 18 (9.2%), VDD in 17 (8.7%) and AAIR in 2 (1.0%) cases. ECG indication was second degree heart block in 40, third degree heart block in 86, chronic atrial fibrillation with bradyarrhythmia in 57, sick sinus syndrome in 27 cases and trifascicular block in one case. The symptoms included dizziness in 126, syncope in 52, dyspnea in 45, bradycardia in 12, chest pain in 3 and cerebral dysfunction in 2 cases. In conclusion, our patients now receive appropriate treatment within a shorter time, thus reducing pressure upon large cardiac surgery centers. However, efforts should be continuously invested in approaching European standards of artificial pacemaker implantation.
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PMID:The first seven years of implantation of permanent cardiac pacemakers in a small urban community in central Croatia. 1938 70

Beta-blockers were documented to reduce reinfarction rate more than 3 decades ago and subsequently touted as being cardioprotective for a broad spectrum of cardiovascular indications such as hypertension, diabetes, angina, atrial fibrillation as well as perioperatively in patients undergoing surgery. However, despite lowering blood pressure, beta-blockers have never shown to reduce morbidity and mortality in uncomplicated hypertension. Also, beta-blockers do not prevent heart failure in hypertension any better than any other antihypertensive drug class. Beta-blockers have been shown to increase the risk on new onset diabetes. When compared with nondiuretic antihypertensive drugs, beta-blockers increase all-cause mortality by 8% and stroke by 30% in patients with new onset diabetes. Beta-blockers are useful for rate control in patients with chronic atrial fibrillation but do not help restore sinus rhythm or have antifibrillatory effects in the atria. Beta-blockers provide symptomatic relief in patients with chronic stable angina but do not reduce the risk of myocardial infarction. Adverse effects of beta-blockers are common including fatigue, dizziness, depression and sexual dysfunction. However, beta-blockers remain a cornerstone in the management of patients having suffered a myocardial infarction and for patients with heart failure. Thus, recent evidence argues against universal cardioprotective properties of beta-blockers but attest to their usefulness for specific cardiovascular indications.
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PMID:Cardioprotection with beta-blockers: myths, facts and Pascal's wager. 1970 92