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)

In 37 (70%) of 53 patients with idiopathic ventricular tachycardia (VT), episodes were mainly related to exercise (group 1). These patients were younger (33 +/- 14 vs 44 +/- 18 years, p = 0.015) and more often had dizziness during VT (71 vs 40%, p = 0.003) than the 16 patients in whom VT was not exercise-related (group 2). Patients in group 1 needed cardioversion less often to terminate the arrhythmia (4 (11%) vs 6 (40%), group 2 [p = 0.04]). VT was initiated during exercise testing in 62% of patients in group 1 but in only 1 patient in group 2 (p = 0.0004). Induction of clinical VT during programmed stimulation was observed in a similar percentage in group 1 (49%) and group 2 (50%) patients. Isoproterenol infusion facilitated the induction of VT in 9 of 20 (45%) group 1 and in 2 of 8 (25%) group 2 patients (p = not significant). After a mean follow-up of 2.9 +/- 2.5 years, 8 (22%) group 1 patients and 5 (31%) group 2 had at least 1 episode of symptomatic VT. Only 1 patient died suddenly. Class III drugs were the most useful in preventing recurrences. Beta-blocking agents were of little value in both groups. Patients with VT and a structurally normal heart have a good prognosis despite recurrences of their arrhythmia. The relation of the arrhythmia to exercise has no prognostic implications.
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PMID:Clinical and electrophysiologic characteristics of exercise-related idiopathic ventricular tachycardia. 192 48

Classically, the frequency of latent left-sided Kent bundles and ventricular tachycardia (VT) is increased in mitral valve prolapse (MVP). To verify this hypothesis, 23 patients with clinical and echocardiographic (M mode and 2D) signs of MVP underwent electrophysiological studies for dizziness or syncope (12 cases) or palpitations (11 cases). In addition to the standard electrophysiological studies, analysis of sinoatrial and atrioventricular conduction, they underwent programmed ventricular pacing (St V2): coupled and then paired St V2 in sinus rhythm and during ventricular pacing (100-150/min) under basal conditions (15 patients), after injection of 2 mg Atropine (6 patients), and 10 micrograms of Isoproterenol (4 patients). These manoeuvres showed that symptoms of dizziness were due to increased vagal tone in 6 cases (associated with paroxysmal nodal tachycardia--PNT--in 3 cases), to sinoatrial block in 2 cases (associated with atrial tachycardia in 1 case), to suprahisian conduction defects in 3 cases (associated with atrial tachycardia in 1 case) and to VT in 1 case. Palpitations were due to VT in 1 case, atrial tachycardia in 1 case and PNT in 9 cases. Our analysis showed a high incidence of PNT (10 cases) with normal inter critical ECG. These arrhythmias were due to intranodal reentry in 7 cases (70%), to a latent left-sided Kent bundle in 2 cases and to a paraseptal Kent bundle in 1 case. These PNT were characterised by induction during exercise (6 cases) and by their association with flutter-type reentry (5 cases).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Mitral valve prolapse. Results of electrophysiological studies]. 392 28

In symptomatic mitral valve prolapse patients (MVP): (1) the frequency and nature of symptoms were analyzed (n = 313); (2) metabolic studies were performed (n = 20), and (3) the response to isoproterenol infusions were studied (n = 16). Chest pain is more often the initial symptom in men; palpitations are more common initially in women. Fatigue, palpitations, dyspnea and arrhythmias are more frequent in women. Chest pain and neurologic events occur with the same frequency in both sexes. Women have more symptoms than men. MVP patients have normal thyroid function tests, normal plasma cortisol, normal diurnal variation of cortisol and normal 24-hour 17-ketosteroids and 17-hydroxycortico-steroids excretion. They have a normal response to oral glucose but higher glucose and insulin levels than controls. MVP patients have increased 24-hour urinary catecholamine excretion. Isoproterenol infusions produce symptoms in a dose-related fashion in MVP patients but not in controls. Isoproterenol infusion-related symptoms included chest pain (7), extreme fatigue (6), dyspnea (6), dizziness (4), numbness (2), panic attacks (2). Isoproterenol infusions produced a greater increase in heart rate in MVP patients compared to controls. Thus, MVP patients have increased catecholamines and hyperresponse to isoproterenol infusion which indicates that their symptoms may be catecholamine related or mediated. The complex relationships of MVP symptoms are not clear; the coexistence of anxiety states and MVP is one explanation; another equally plausible explanation is that MVP may be a specific marker for the symptom complex.
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PMID:Mitral valve prolapse: a marker for anxiety or overlapping phenomenon? 636 71

Prolapsed mitral valve prolapse (PMV) is classically associated with disorders of ventricular excitability whose significance is unclear. However, syncope can suggest the possibility of a serious ventricular arrhythmia. The objective of this study was to try to identify the mechanisms of dizziness and syncope associated with PMV. We report the results of programmed atrial and ventricular stimulation performed under baseline conditions and after administration of Isuprel in 56 patients with PMV: 27 patients had a history of presyncope or syncope (group I), 14 had spontaneous atrial or supraventricular tachycardias without dizziness or syncope (group II) and 15 were asymptomatic and investigated for VEBs or conduction disorders (group III). The following results were obtained: In group I, 6 patients experienced sustained inducible ventricular tachycardia (VT); an atrial tachycardia (atrial tachycardia and/or atrial fibrillation) (AT) was also induced in 5 of them. In another 19 patients, a supraventricular tachycardia (SVT) and/or AT was induced. A total of 24 atrial or junctional tachycardias were triggered in this group. In group II, AT and/or SVT were reproduced in 13 out of 14 cases (93%). In group III, AT was triggered in 3 patients (20%). SVT were induced by Isuprel while AT were triggered prior to administration of Isuprel, under baseline conditions, and 3 of them were reproduced during vagal manoeuvres. A ventricular arrhythmogenic effect was observed in two cases in group II while taking class I antiarrhythmics. In conclusion, spontaneous AT and SVT of PMV are easily inducible with a sensitivity of 93%, but are difficult to induce in asymptomatic subjects. The high incidence of TA and SVT in the case of unexplained presyncope in subjects without documented tachycardia therefore appears to be suggestive of a relationship between these presyncopes and AT or SVT. However, the search for VT should take precedence. SVT appear to be catecholaminergic while AT tend to be vagal.
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PMID:[Syncopes associated with mitral valve prolapse. Mechanisms]. 876 45

In the paper we have described a case of acute, unintentional intoxication with clenbuterol, a selective beta 2-agonist. A 21-year-old bodybuilder to improve his physical fitness and to increase his muscle bulk was using clenbuterol in a dose of two tablets (20 mg) daily for a week before poisoning. On a day of acute intoxication he drank orange juice containing 48 tablets (4.8 g) of clenbuterol, which had been placed there by his friends. The patient was admitted to our clinic with tachycardia at rate 160 bpm, headache, dizziness, tremor, sweats, muscle weakness, agitation. Serum potassium concentration was 2.6 mmol/L, blood glucose level 18.7 mmol/L. All the symptoms and biochemical abnormalities disappeared after intravenous treatment with propranolol (1.0 mg) and potassium chloride (60 mmol) within five hour period. This case indicates that more attention should be paid to clenbuterol widely used as a stimulant by athletes, especially by bodybuilders.
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PMID:Acute poisoning with clenbuterol--a case report. 947 4

A 21-year-old woman presented with an acute febrile illness after a two-week holiday in Jamaica. Her symptoms started two days after return, with sudden onset of continuous high fever (> 39 degrees C), dizziness and nausea. Three days later she developed a generalized macular rash, which led to the tentative diagnosis "acute dengue fever." Laboratory confirmation was achieved by demonstrating anti-dengue IgM and IgG antibodies in paired sera; in addition, flavivirus particles were directly visualized by electron microscopy.
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PMID:Rapid diagnosis of primary dengue fever by the immunochromatographic test and by electron microscopy--a case report. 1062 99

Sudden death is a tragic complication of hypertrophic cardiomyopathy. We report the case of a young patient with hypertrophic cardiomyopathy in whom an episode of atrial fibrillation triggered ventricular fibrillation and cardiac arrest. A 21-year-old man with nonobstructive hypertrophic cardiomyopathy underwent cardioverter-defibrillator implantation for primary prevention of sudden death, after risk stratification with noninvasive strategies. After 6 weeks, during a moderate effort, the patient had a syncopal episode, preceded by palpitations and dizziness, and terminated by the cardioverter-defibrillator. Device interrogation revealed an episode of atrial fibrillation with high ventricular response, spontaneously followed by ventricular tachycardia/fibrillation. Atrial fibrillation is a potential trigger of life-threatening arrhythmias and sudden death in patients with hypertrophic cardiomyopathy. Clinical investigation of risk markers for sudden death should be encouraged to identify high-risk patients who may benefit from a prophylactic therapy with an implantable cardioverter-defibrillator.
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PMID:Noninvasive risk stratification prevents sudden death due to paroxysmal atrial fibrillation in hypertrophic cardiomyopathy. 1693 87

Bicuspid aortic valve is the most common congenital cardiac anomaly and it may often coexist with other congenital cardiac anomalies. Its coexistence with discrete subaortic membrane, causing obstruction of the left ventricular outflow tract is very rare. A 21-year-old male patient presented with complaints of exertional dyspnea and dizziness. On transthoracic echocardiography, the parasternal short-axis view showed a bicuspid aortic valve, and parasternal long-axis color Doppler view showed a mosaic pattern in the subaortic region. A more careful examination of the parasternal long-axis views revealed a discrete subaortic membrane. Continuous-wave Doppler flow velocity obtained from the aortic valve was normal; however, a peak gradient of 30 mmHg was observed with the Valsalva maneuver. The fact that there are very few reports on this rare coexistence may be due to failure to recognize discrete subaortic membrane during echocardiographic examination.
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PMID:[Obstruction of the left ventricular outflow tract caused by bicuspid aortic valve and discrete subaortic membrane]. 1915 62

A 21 years old male presented with low grade fever, hemoptysis and progressively increasing dyspnoea of four month duration followed by acutely developing dizziness, hypotension, convulsion and altered sensorium. He had been operated (left inguinal orchidectomy) for left testicular swelling two years back with high alpha-fetoprotein and normal beta-human chorionic gonadotropin (beta-hCG). In view of this a possibility of metastasis secondary to a malignant testicular tumor was considered. Echocardiography demonstrated a large intracardiac mass, chest computed tomography (CT) revealed intracardiac mass, mediastinal masses and left sided pleural effusion. The histopathology revealed testicular mixed germ cell tumor (MGCT). This case is presented to demonstrate uncommon cardiac manifestations of secondary spread of testicular malignancy.
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PMID:Testicular mixed germ cell tumor metastasizing to heart. 1926 11

The athletic performance supplement industry is a multibillion-dollar business and one popular category claims to increase nitric oxide (NO) production. We report three patients presenting to the emergency department with adverse effects. A 33-year-old man presented with palpitations, dizziness, vomiting, and syncope, after the use of NO(2) platinum. His examination and electrocardiogram (ECG) were normal. The dizziness persisted, requiring admission overnight. A 21-year-old man with palpitations and near syncope had used a "nitric oxide" supplement. He was tachycardic to 115 bpm with otherwise normal examination. Laboratory values including methemoglobin, and ECG were unremarkable. He was treated with 1 L of saline with no change in heart rate. He was admitted for observation. A 24-year-old man presented after taking NO-Xplode with palpitations and a headache. His examination, laboratory values, and ECG were normal. He was discharged. The purported active ingredient in these products is arginine alpha-ketoglutarate (AAKG), which is claimed to increase NO production by supplying the precursor L-arginine. The symptoms could be due to vasodilation from increased levels of NO, though other etiologies cannot be excluded. AAKG containing supplements may be associated with adverse effects requiring hospital admission.
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PMID:Adverse effects associated with arginine alpha-ketoglutarate containing supplements. 1975 57


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