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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The literature for coronary artery disease as well as ischemic and dilated cardiomyopathy suggests that ventricular arrhythmias and left ventricular dysfunction are independent risk factors for sudden death, but that the presence of organic heart disease provides the substrate for potentially lethal arrhythmias. Patients with a cardiomyopathy and ventricular tachycardia are at a high risk for sudden death as a group. The general risk, then, is high for the group with CHF and arrhythmias. The prognostic indices for hypertrophic cardiomyopathy are imprecise, but the risk for sudden death for the group is high in the young and remains high even among the adult survivors. Many conditions associated with CHF and its treatment may lead to arrhythmias and are potentially reversible. Most studies suggest that EPS and exercise provocation have limited power in predicting the risk to the individual patient. Therapeutically, reversible causes of arrhythmias should be sought and corrected. In general, antiarrhythmic drug therapy has been disappointing with adequate control being achieved in only about 30 per cent of patients and uncertainties about the effectiveness of such therapy in altering long-term prognosis. This is due to various causes including the inability to find an effective drug, problems with patient compliance, the failure of physicians to properly monitor drug levels, and changes in the anatomical and physiologic substrate due to disease and therapy. Surgical ablation or resection of arrhythmogenic foci is effective in selected patients. The AICD will become first-line therapy in patients at high risk for sudden death due to ventricular arrhythmias, with antiarrhythmic drugs and other approaches being used to minimize the frequency of the arrhythmias.
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PMID:Management of arrhythmias in heart failure. 265 Aug 69

The two new methods for defining arrhythmic syncope described in this report represent important additions to the traditional syncope workup. Both techniques uncovered a substantial number of arrhythmic causes of syncope which had not been found by standard techniques. A major strength of each method is that symptoms can be directly related to the arrhythmia. The 68% incidence of diagnostic EPS abnormalities which we found was identical to the study of DiMarco but higher than reported by others (which have ranged from 12 to 48%) (18, 20, 21). More critical patient selection and more comprehensive study techniques most likely account for these differences. It is our opinion that a significant number of patients whose diagnosis was "syncope of undetermined etiology" in previous studies did indeed have an arrhythmic basis for their symptoms which was not identified. At this point the issue of "cost effectiveness" inevitably arises. Do all patients with syncope in whom a cause is not initially apparent (i.e., up to 50% of such patients) require either TTEM or EPS? The answer is obviously no, not for this whole population. However, the evident power of TTEM and EPS requires that the question should be raised. Furthermore, the results of the invasive EPS study strongly suggest that mortality and morbidity can be reduced. Table 11 shows the relative costs for all of the diagnostic tests for arrhythmic syncope. From this it can be seen that TTEM is quite inexpensive and therefore very cost-effective. It is an ideal adjunct to 24 hour ambulatory monitoring in selected patients. Although invasive EPS studies are costly, it is not difficult to incur equal costs by use of several days of prolonged monitoring, especially if done in the hospital. Thus, in identified patients with abnormal but "not diagnostic" ambulatory monitoring studies, patients with abrupt syncope, patients with frequent symptoms or patients with known underlying heart disease, further evaluation with TTEM or EPS should be strongly considered.
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PMID:Arrhythmic syncope: what to do when ambulatory monitoring is non-diagnostic. 653 75

The interest of electrohysiological study for the prognostic evaluation of asymptomatic Wolff-Parkinson-White (WPW) syndrome remains controversial. We report the case of an asymptomatic 67-year-old man without heart disease in whom a type A WPW syndrome was noted. Because the WPW was unchanged during exercise testing, transesophageal EPS was performed. In basal state, 1/1 conduction through the Kent bundle was noted up to a rate of 210 beats/min. After infusion of 30 microg of isoproterenol, atrial pacing was associated with a 1/1 conduction throughout the Kent bundle at a rate at 300 beats/min and induced rapid atrial fibrillation which was stopped by flecainide. No treatment was indicated. Nine years later, at age 76, the patient developed syncope related to rapid atrial fibrillation requiring cardioversion. In conclusion, the occurrence of a potentially lethal supraventricular tachyarrhythmia in a previously asymptomatic patient with WPW syndrome might be encountered in elderly patients. Transesophageal electrophysiological evaluation is a useful means to predict this risk.
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PMID:Atrial fibrillation with a very rapid ventricular response as the first clinical arrhythmia in a 76-year-old man. 1287 14

We describe a case of abnormal right atrial (RA) conduction in a patient with atrial tachycardia (AT) but no history of structural heart disease or cardiac surgery. Following ablation of AT, the patient experienced typical atrial flutter (AFL) and a postcardioversion ECG suggestive of low atrial rhythm. Repeat EPS and three-dimensional electroanatomic activation mapping showed unusual RA activation during SR. This case illustrates the possibility that abnormal intraatrial conduction may lead to unusual patterns of activation in the RA which can serve as a necessary substrate for the initiation and maintenance of macro-reentry circuits.
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PMID:Right atrial tachycardia in a patient with severe atrial conduction disturbances and an anatomically normal heart. 1595 98

Patients with adult congenital heart disease are at increased risk of ventricular arrhythmia (VA) and sudden cardiac death, although no clear predictors have been found. Ventricular programmed stimulation has been shown to predict clinical ventricular tachycardia and sudden death events, but the role of screening electrophysiology studies (S-EPSs) in this population remains poorly defined. Therefore, we sought to determine the prevalence of inducible VA and to evaluate the clinical predictors in a heterogeneous group of patients with adult congenital heart disease (> or =18 years old) undergoing S-EPSs at preoperative or interventional cardiac catheterization. Studies for the primary evaluation of clinical VA were excluded. The demographic, clinical, and diagnostic findings were compared between the patients with positive and negative findings. From 2005 to 2009, 80 patients (mean age 30 +/- 9 years) underwent S-EPSs, and 23 had inducible VA. The diagnoses for those with studies positive for VA included tetralogy of Fallot (n = 12), d-transposition of the great arteries (n = 6), pulmonary stenosis (n = 2), double outlet right ventricle (n = 1), double inlet left ventricle (n = 1), and Ebstein's anomaly (n = 1). Men were significantly more likely to have a S-EPS positive for VA (p = 0.015). Increasing QRS duration, decreasing peak oxygen uptake (percentage of predicted), and ventricular fibrosis with cardiovascular magnetic resonance imaging were significantly associated with studies positive for VA (p <0.05). Combined fibrosis and a peak oxygen uptake <80% of predicted had 100% sensitivity for positive VA findings. In conclusion, almost 30% of those with adult congenital heart disease undergoing S-EPSs had inducible VA. A prolonged QRS duration, diminished exercise capacity, and the presence of ventricular fibrosis were significantly associated with findings positive for VA and might improve patient selection for screening evaluations.
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PMID:Rate of inducible ventricular arrhythmia in adults with congenital heart disease. 2072 54