الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Atrial fibrillation (AF) is the most common form of cardiac arrhythmia and its prevalence increases with age, reaching 8% in those older than 80 years. AF is associated with an increased risk of stroke, heart failure, and mortality. AF causes electrical and structural changes to the atria which play an important role in the perpetuation and progression of the arrhythmia. This process is referred to as atrial remodeling. Hypertension is one of the confirmed predisposing conditions for the development of AF. AF is associated with clinical and hemodynamic deterioration and may predispose to systemic thromboembolism and poorer clinical outcomes in hypertensive patients. Therefore, the early detection of patients with hypertension at risk of developing AF may have important clinical implications in choosing preventive measures and treatment strategies. The occurrence of paroxysmal atrial fibrillation in hypertension is associated with enlargement of the left atrium, depression of its contractile function and “normalization” of the pattern of left ventricular filling and is independent of left ventricular hypertrophy and systolic wall stress. Previous studies have shown that prolonged, inhomogeneous, and anisotropic distribution of connections between myocardial fibers results in the discontinuous anisotropic propagation of sinus impulses. The inhomogeneous and discontinuous atrial conduction in patientswith paroxysmal AF (PAF) has been recently evaluated with a simple electrocardiographic (ECG) index using P wave. Recently, a novel echocardiographic parameter based on tissue Doppler imaging (TDI) has been introduced to assess the atrial electromechanical time: the PA-TDI duration and atrial electromechanical delay. Potentially, these new parameters provide a more accurate assessment of the presence and extent of atrial remodeling than conventional echocardiographic parameters. The study is aimed to investigate the predictive indicators for paroxysmal AF in hypertensive patients using P wave and transthoracic echocardiography with the use of Tissue Doppler imaging (TDI). This study was conducted at Cardiology Department of Tanta University Hospital and included 100 known hypertensive adult patients, 50 of them diagnosed to have paroxysmal AF, and the other 50 hypertensive adult patients, age and sex matched with normal sinus rhythm as a control group.