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Common Arrhythmia (common + arrhythmia)
Selected AbstractsThe Spectrum of Long-term Electrophysiologic Abnormalities in Patients with Univentricular HeartsCONGENITAL HEART DISEASE, Issue 5 2009Kathryn K. Collins MD ABSTRACT Patients with univentricular hearts experience a wide range of electrophysiolgic abnormalities which tend to develop years after cardiovascular surgical interventions. Intra-atrial reentrant tachycardia (atrial flutter) in the Fontan population is the most common arrhythmia and, as such, has the largest body of literature addressing its cause and treatment. However, sinus node dysfunction, other atrial arrhythmias, ventricular arrhythmias, and cardiac dysynchrony also occur in this patient population. The purpose of this article is to review the prevalence, mechanisms, and treatment of these electrophysiologic abnormalities within the single ventricle and Fontan patient. [source] Transesophageal Echocardiography Risk Factors for Stroke in Nonvalvular Atrial FibrillationECHOCARDIOGRAPHY, Issue 4 2000F.R.C.P.C., SUSAN M. FAGAN M.D. Atrial fibrillation is a common arrhythmia, particularly in the older age groups. It confers an increased risk of thromboembolism to these patients, and multiple clinical risk factors have been identified to be useful in predicting the risks of thromboembolic events. Recent studies have evaluated the role of transesophageal echocardiography (TEE) in the evaluation of patients with atrial fibrillation. The purpose of this review is to evaluate the significance of transesophageal echocardiography findings in the prediction of thromboembolic events, particularly stroke, in patients with nonvalvular atrial fibrillation, with an emphasis on recently reported prospective studies. Aortic plaque and left atrial appendage abnormalities are identified as independent predictors of thromboembolic events. Although they are associated with clinical events, they also have independent incremental prognostic values. Other transesophageal echocardiographic findings, such as patent foramen ovale and atrial septal aneurysm, have not been found to be predictors of thromboembolic events in this patient group. Thus, TEE is a useful tool in stratifying patients with nonvalvular atrial fibrillation into different risk groups in terms of thromboembolic events, and it will likely play an important role in future studies to assess new treatment strategies in high-risk patients with atrial fibrillation. [source] Is There a Role for Statins in Atrial Fibrillation?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2009DAVID E. DAWE M.D. 3-Hydroxy-3-methyl-glutaryl-CoA reductase inhibitors (statins) are some of the most commonly prescribed drugs in the world. While lipid modification remains the primary function of statins, there has been increasing interest in its potential pleiotropic effects, particularly as an anti-inflammatory agent in its role as an antiarrhythmic. Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and carries with it a significant burden in both morbidity and mortality. Treatment for AF currently involves either rate or rhythm control where both have demonstrable associated risks. Rate control necessitates anticoagulation, which can cause life-threatening bleeding, while rhythm control has a poor side-effect profile that may lead to greater mortality and may not completely eliminate the need for anticoagulation. Considering this pressing need for novel therapeutic interventions in AF, this long overdue systematic review explores the potential role of statins in the treatment and prevention of AF. Physicians, especially cardiologists, need to be aware of the host of currently available literature and, more importantly, need to be stimulated to generate discussion and formulate studies that will help debate the issues under the most erudite standards. [source] Relation of Age and Sex to Atrial Electrophysiological Properties in Patients with No History of Atrial FibrillationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2003KOICHI SAKABE Although atrial fibrillation is a common arrhythmia, especially in elderly men, little is known about age related changes in atrial electrophysiological properties or gender differences. The aim of this study was to analyze the effects of aging on vulnerability to atrial fibrillation and assessed gender differences in those age related changes. An electrophysiological study was performed on 73 patients with no history of atrial fibrillation, structural heart disease, or conditions with potential effects on cardiac hemodynamic or electrophysiological function, including 25 women (mean age 49 ± 18 years; range 12,84 years). The following atrial excitability parameters were assessed: spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation(A2/A1 × 100), effective refractory period, wavelength index (effective refractory period/A2), and inducibility of atrial fibrillation. There were no significant differences in percent maximum atrial fragmentation (143 ± 28vs142 ± 35%), effective refractory period (241 ± 39vs238 ± 50 ms), wavelength index (2.9 ± 0.8vs3.1 ± 0.9), induction of atrial fibrillation (10 [21%] vs 7 [28%]), or age (50 ± 17vs 49 ± 20 years) between men and women. Age was not statistically different between those patients with and without induction of atrial fibrillation in men (48 ± 14vs50 ± 18 years) and women (48 ± 18vs49 ± 21 years). Percent maximum atrial fragmentation and effective refractory period were directly correlated with age in men (r = 0.35, P = 0.01; r = 0.46, P < 0.001, respectively) and women (r = 0.42, P = 0.04; r = 0.45, P = 0.02, respectively), though wavelength index did not correlate with age in men (r =,0.04) or women (r =,0.04) with no history of atrial fibrillation. Considering these findings, the authors conclude that the mechanism triggering atrial fibrillation may be different between older and younger patients with atrial fibrillation, because younger patients who have no marked substrate for atrial fibrillation may need many trigger beats to induce atrial fibrillation. (PACE 2003; 26:1238,1244) [source] Differences in the morphology and duration between premature P waves and the preceding sinus complexes in patients with a history of paroxysmal atrial fibrillationCLINICAL CARDIOLOGY, Issue 7 2003Polychronis E. Dilaveris M.D. Abstract Background: Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Experimental and human mapping studies have demonstrated that perpetuation of AF is due to the presence of multiple reentrant wavelets with various sizes in the right and left atria. Hypothesis: Atrial fibrillation may be induced by atrial ectopic beats originating in the pulmonary veins, and premature P-wave (PPW) patterns may help to identify the source of firing. Methods: To evaluate the morphology and duration of PPWs, 12-lead digital electrocardiogram (ECG) strips containing clearly definable PPWs not merging with the preceding T waves were obtained in 25 patients with AF history (9 men, mean age 59.5 ± 2.2 years) and 25 subjects without any previous AF history (11 men, mean age 53.6 ± 2.5 years). The polarity of PPWs was evaluated in all 12 ECG leads. Previously described indices, such as P maximum, P dispersion (= P maximum ,P minimum), P mean, and P standard deviation were also calculated. Results: Premature P-wave patterns were characterized by more positive P waves in lead V1. All P-wave analysis indices were significantly higher in patients with AF than in controls when calculated in the sinus beat, whereas they did not differ between the two groups when calculated in the PPW. P-wave indices did not differ between the PPW and the sinus P wave in either patients with AF or controls, except for P mean, which was significantly higher in the sinus (110.1 ± 1.7 ms) than in the PPW (100 ± 2 ms) only in patients with AF (p = 0.001). Conclusion: The evaluation of PPW patterns is only feasible in a small percentage of short-lasting digital 12-lead ECG recordings containing ectopic atrial beats. Premature P wave patterns are characterized by more positive P waves in lead V1, which indicates a left atrial origin in the ectopic foci. The observed differences in P-wave analysis indices between patients with AF and controls and between sinus beats and PPWs may be attributed to the presence of electrophysiologic changes in the atrial substrate. [source] | ||||||||||