31K views · 361 reactions | #Sinoatrial (SA) node #arrhythmias, also known as sinus node dysfunction or sick sinus syndrome, occur when the heart's natural pacemaker (SA node) doesn't function properly, leading to abnormal heart rhythms. These arrhythmias can include slow heart rates (bradycardia), fast heart rates (tachycardia), or a combination of both, potentially causing symptoms like lightheadedness, dizziness, and fatigue. #education #ECG #doctor #medicalstudent #nurses | Med G | Facebook