NHA EKG Module 2: EKG Acquisition Question and answer 2023

NHA EKG Module 2: EKG Acquisition Question and answer 2023Which valves are atrioventricular valves? tricuspid and bicuspid Which valves are semilunar valves? aortic and pulmonary Which vessels arise from the root of the aorta? right and left coronary arteries What does the left main coronary artery split into? left circumflex (LCx) and left anterior descending (LAD) arteries Occlusion of what vessel can lead to ventricular arrhythmia and death? left anterior descending artery (LAD) SA node natural pacemaker of the heart rate: 60-100 located in the right atrial wall Occlusion of the SA node artery can manifest...? extreme sinus brady What two vessels branch off from the RCA? sinoatrial node artery and atrioventricular node artery AV node rate: 40-60 - holds electrical signal received from SA node to allow ventricles to fill with blood what shows on the EKG tracing when the AV node is not conducting as expected? increases PR interval Why does a complete heart block happen? the AV node is unable to conduct electrical impulses from SA node to the ventricles What happens when there is occlusion of the AV node artery? high-degree heart block Collateral circulation circulation formed by smaller blood vessels branching off from or near larger, occluded blood vessels Why don't patients with coronary heart disease experience symptoms until it is in advanced stages? collateral vessels compensate for reduced oxygen supply ectopic beats Impulses originating outside normal conduction pathways of the heart. How are ectopic beats seen on an EKG tracing? premature atrial complex, premature junctional complex, premature ventricular complex Bundle of His where the AV node conducts its impulse to Right bundle branch (RBB) - carries impulses from Bundle of His to purkinje fibers of right ventricle - causes right ventricular depolarization What vessel supplies the RBB and LBB with blood? LAD Left bundle branch (LBB) - carries impulse from Bundle of His to purkinje fibers of the left ventricle - causes left ventricular depolartization What is different between LBB and RBB? LBB is shorter and divides into left anterior fascicle and left posterior fascicle left anterior fascicle receives additional blood supply from...? RCA ischemia Lack of blood supply to a body part or an organ purkinje fibers rate: 20-40/min travel across the surface of the ventricles to depolarize them What is important about the purkinje fibers? they initiate myocardial contraction what is the standard speed of an EKG tracing? 25 mm/sec what is the standard amplitude of an EKG tracing? 10 mm/mV what is the "x axis" on EKG paper? time what is the "y axis" on EKG paper? voltage what does one small box on EKG paper represent (3 units, 3 values) ? 1 mm, 0.1 mV vertical , 0.04 sec horizontal what does one big box on EKG paper represent (3 units, 3 values) ? 5 mm, 0.5 mV vertical , 0.20 sec horizontal unipolar leads positive end of the lead system; augmented leads, chest leads augmented leads aVR, aVL, aVF; considered unipolar because there is a single positive electrode referenced against the combination of the other limb leads bipolar leads standard limb leads; leads I, II, III Eindhoven's Triangle how often should you perform inspections of EKG paper? DAILY What does a thick band of color on the border of the EKG paper indicate? paper is running low poorly cleaned equipment or plugs that don't fit properly can lead to... artifact steps to conducting an EKG tracing? 1) ensure you have all of the supplies needed for testing 2) instruct patients to avoid applying any substances on their skin 3) request permission from patient to clip/shave hair at electrode site placement if necessary what is the standard position for a 12 lead EKG? supine with no pillows