NURS 5354 EKG Exam Questions And Answers Verified 100% Correct

NURS 5354 EKG Exam Questions And Answers Verified 100% Correct A large square which contains five boxes across and five boxes down is - ANSWER -.2 sec and 0.5mV Speed equates to - ANSWER -the # of complexes on a ECG strip = HR Isoelectric line - ANSWER -designates the flat part of the diagram between the P wave and T wave & significant variations in positive and negative deflections can correlate with certain diseases or disorders Appear above the isoelectric line - ANSWER -Positive deflections Appear below the isoelectric line - ANSWER -Negative deflections P wave - ANSWER -first positive deflection. The P wave should be less than 0.12 secs Abnormalities in the P wave best seen in - ANSWER -inferior leads (Leads II, III, and aVF) because the wave is more prominent in these leads PR interval - ANSWER -Reflects conduction through the AV node. 0.12 to 0.2 secs. Represents the onset of the P wave to the start of the QRS complex Normal QRS interval - ANSWER -is less than .12 secs. The normal range is 0.08 to 0.12 secs Normal QT interval - ANSWER -amount of time for the ventricles to depolarize and repolarize (0.36 - 0.44 seconds) normally= 0.42 secs. Shortens with tachy HR and Lenghthens with Brady HR Bazett formula - ANSWER -calculate the QTc or the corrected QT interval QRS complex represents - ANSWER -ventricular depolarization Q wave - ANSWER -first negative deflection after the P-wave R wave - ANSWER -first positive deflection after the P-wave S-wave - ANSWER -first negative deflection after the R-wave Second positive deflection QRS - ANSWER -R prime and is commonly seen in a bundle branch block Second negative deflection QRS - ANSWER -S prime: following the initial negative deflection after the R-wave Pathological Q-waves indicate - ANSWER -myocardial infarction (or dead myocardium) that is either current or prior and represented in 2 contiguous leads Q-wave considered pathologic the Q-wave duration needs to be - ANSWER 0.04 secs, or greater than 25% of the R wave R wave - ANSWER -should be small in Lead V Normal R wave progression - ANSWER -happens when R wave becomes larger throughout the precordial leads. Eventually R wave becomes larger than the S wave with the S wave significantly smaller in V6 J point - ANSWER -point where the QRS complex ends and the ST segment begins. The J-point is even with the isoelectric line. Following the J-point is - ANSWER -ST segment ST segment - ANSWER -Period following completion of ventricular depolarization & prior to ventricular repolarization. & its even with the isoelectric line. Changes in the J-point and ST segment may result in - ANSWER -ST depression or elevation The level of ST depression or elevation is highly variable on - ANSWER -the etiology causing the change ST elevation or depression ideally should be measured with reference to the - ANSWER -TP segment (which is the measurement from the end of the T wave to the next P wave) - ANSWER - TP segment represents - ANSWER -electrical silence in the heart muscle & should be measured at the isoelectric line ST segment is evaluated with the - ANSWER -T wave due to the reflection of ischemic insult or injury ST depression and/or T wave inversion - ANSWER -Myocardial ischemia ST elevation - ANSWER -Myocardial injury isnt by ST or T wave changes but Development of Q waves - ANSWER -Myocardial infarction The T wave is - ANSWER -positive or negative deflection following the QRS complex & asymmetric T wave is a positive deflection - ANSWER -In most leads except lead V1 & aVR T wave is a negative deflection - ANSWER -lead V1 & aVR Symmetrical T wave is associated with - ANSWER -Ischemia and electrolyte disturbances Primary axis - ANSWER -QRS complex, located in frontal plane, the six limb leads are used to determine the axis.