Cardiac electrophysiology and ECG interpretation
Principles of cardiac electrophysiology and electrocardiography (ECG) To ensure effective cardiac pumping function, the atria and the ventricles must be activated rapidly and sequentially. Rapid activation is important in order to activate as much myocardium simultaneously as possible; the more myocardium contracting at the same time the more efficient the pumping mechanism. Sequential activation implies that the atria are activated first and they fill the ventricles with adequate volumes of blood before ventricular contraction commences. To coordinate these two tasks, the heart has an electrical conduction system composed of specialized myocardial cells (henceforth referred to as conduction cells). These cells form bundles of fibers that act as electrical cords that spread the action potential rapidly and sequentially to contractile myocardium in the atria and the ventricles. When the contractile myocardium receives the action potential, it is activated and contracts. Figure 1 illust…
Cuộc đời thì ngắn, mà nghề thì miên man;cơn bệnh phập phù;kinh nghiệm hiểm nguy, còn quyết định thì thật khó.Người thầy thuốc không phải chỉ chuẩn bị để tự mình làm đúng, mà còn khiến cho bệnh nhân, người đi theo và các yếu tố xung quanh hợp tác hài…
