Sirenko-Tagirova et al., "A coupled-clock system drives the automaticity of human sinoatrial
nodal pacemaker cells," Science Signaling, vol.
In the first place, cocaine has a direct cardiotoxic effect, due its ability to block voltage-dependent K+ and Na++ channels in the sinoatrial
node and the myocardium, leading to reduced contractility and to prolongation of the QT interval and the QRS complex.
Pathophysiological view on AF is the shortage of refractory time in atrial cardiomyocytes' and increased sinoatrial
activity , which causes difficulties to keep sinus rhythm, particularly in older people with some accompanying cardiac disorders like e.g.
For example, researchers need to better understand the mechanisms controlling the development and maintenance of pacemaker cells in the sinoatrial
node, just as they must develop ways to compare experimental biological pacemaker tissue with bona fide sinoatrial
The atria and ventricles beat independent of each other under the control of a separate pacemaker foci: one in the sinoatrial
node and the other in the AV junction.
node has a natural frequency of about 90 beats per min.
Low-frequency extracellular potentials recorded from the sinoatrial
The pathologic spectrum of atrioventricular conduction abnormalities ranges from first-degree heart block (static lengthening of the PR interval beyond 0.2 s) to third-degree heart block (failure of the sinoatrial
node signal to conduct to the ventricles).
Called the sinoatrial
node, it acts like a metronome to keep the heart pulsing at 60 to 100 beats a minute or so, more when you're active.
(13) A missed beat likely originates from an intrinsic dysfunction of the sinoatrial
The distinction between atherosclerotic/lacunar and embolic was made according to the presence of atrial fibrillation (AF) the characteristics of the lesion in CT and diffusion MR the presence of thrombus in the echocardiography and Doppler ultrasonography valvular heart disease and a history of the use of anticoagulants (warfarin) and the history of the patients (such as a recent attack of MT the presence of cardiomyopathy valvular disease chronic sinoatrial
dysfunction interatrial septal anomaly).Considering the medications used and previous medical records hypertension (HT) diabetes mellitus (DM) and coronary artery disease (CAD) were found in patients.
Because the L-type calcium current is the primary depolarizing current in sinoatrial
and AV nodal cells, a reduction in calcium current can lead to AV block (Hancox and Mitcheson 1997; Kawai et al.