WEEK: LECTURE: HEART DISORDERS 1 ARRHYTHMIAS Occur due to an impulse Formation or conduction abnormality and can be atrial or ventricular issues. A lethal arrhythmia can lead to sudden cardio death (SCD) defined as an unexpected death CAUSES Primary (electrical disorders) Genetic (very rare) Secondary (arrhythmia syndromes) Ischemic injury (most common) Channelopathies Nodes Fibres Na+ Ca 2+ K + CLINICAL MANIFESTATIONS Can be asymptomatic Common Other symptoms/signs Fluttering in the chest Racing heartbeat (tachycardia) Slow heartbeat (bradycardia) Chest pain Shortness of breath (dyspnoea) Fatigue Light headedness or dizziness Sweating Fainting (syncope) or near Fainting PATHOGEN?S?S Ischemic injury is the most common cause through either Direct damage Dilation of heart chambers + Frontal plane Channelopathies Na +, K +, Ca2 + Right atrium O SINOATRIAL (SA) NODE Dysfunction interrupts action potentials Medications Beta blockers Control heartrate Blood thinners MANAGEMENT Therapies 2 ATRIOVENTRICULAR (AV) NODE 3 ATRIOVENTRICULAR (AV) BUNDLE (BUNDLE OF HIS) RIGHT AND LEFT BUNDLE BRANCHES Flight ventricle PURKIN JE FIBRES Vague maneuvers Stimulation of the vagus nerve to elevate symptoms Left atrium - Left ventricle Prevent blood clots Cardioversion Medical procedure that gives quick, low energy shocks to restore heart rhythm Insufficient blood Flow increases risk of blood clots surgery Pacemaker Stabalising rhythm of heart chambers