Humber Final Exam 302 Questions with Verified Answers, Exams of Nursing

Download Humber Final Exam 302 Questions with Verified Answers and more Exams Nursing in PDF only on Docsity! 1 / 30 Cardiology Nursing 1 Humber Final exam 302 questions with verified answers (including diagrams) 1. sinus rhythm- correct answer - regular rhythm Set by SA node at 60 to 100 bpm P waves normal normal qrs PR 0.12 - 0.2 normal qrs less than 0.10 2. wide qrs is- correct answer - greater than 0.12 3. Sinus Tachycardia- correct answer - 100-160 bpm SA node reduced time for ventricle filling assess for SOB or chest pain 4. a prolonged QT interval- correct answer - more prone to arrhythmia 5. NSR reflects the heart's- correct answer - normal electrical activity, providing synchrony between the atria and the ventricles. 6. Sinus tachycardia occurs when the- correct answer - sinus node discharges impulses too fast (100 - 160 beats/minute). All other parameters are normal 7. Facts about sinus tachycardia- correct answer - Normal response of heart in certain circum- stances (for example exercise) • Begins and ends gradually in contrast to other tachycardias • Usually benign arrhythmia that goes away when underlying cause is treated 2 / 30 ulses too slow • Common causes- correct answer - Anxiety, hypoxia, hypovolemia, hypotension, heart failure, pain, drugs that increase sympathetic tone (epinephrine, norepinephrine, dopamine, dobutamine, isoproterenol, nitroprusside), and drugs that decrease parasympathet- ic tone (atropine) • Persistent sinus tachycardia may result in decreased cardiac output due to a decrease in stroke volume. Cardiac output = stroke volume ×heart rate. A decrease in either stroke volume or heart rate may result in a decrease in cardiac output. 8. Sinus bradycardia occurs when- correct answer - the sinus node discharges imp (40 - 60 beats/minute). All other parameters are normal. 9. Sinus bradycardia features- correct answer - regular rhythm, rate 40-60 bpm Normal p waves PR interval normal 0.12 to 0.2 QRS normal less than 0.1 10. Facts about sinus bradycardia- correct answer - Normal response of heart in certain circum- stances (for example relaxation, sleep) • Most common arrhythmia associated with acute inferior wall myocardial infarction • Other causes- correct answer - Reperfusion rhythm following myocardial reperfusion procedures (thrombolytic administration, angioplasty); vagal stimulation; sleep apnea; hyper- kalemia; increased intracranial pressure; disease of SA node; and administration of drugs, such as digitalis, calcium channel blockers, and beta blockers • Persistent bradycardia may result in decreased cardiac output due to a decrease in heart rate. Cardiac output = stroke volume ×heart rate. A decrease in either stroke volume or heart rate may result in a decrease in cardiac output. 11. Treatment of sinus bradycardia- correct answer - No treatment is necessary if patient is asymp- tomatic. 5 / 30 23. The 6 chest leads are...- correct answer - V1—4th interspace, right sternal border V2—4th interspace, left sternal border V3—midway between V2 and V4 V4—5th interspace, left midclavicular line V5—5th interspace, left anterior axillary line V6—5th interspace, left midaxillary line 24. False high rate alarms—- correct answer - Patient turning in bed or extremity movement. So- lution- correct answer - Problem is usually intermittent and no correction is necessary. Movement artifact can be reduced by avoiding placement of electrode pads in areas where extremity movement is greatest (bony areas such as the clavicles). Seizure activity can also produce high voltage artifact potentials 25. False low rate alarms- correct answer - Continuous straight line related to dried conductive gel, disconnected lead wire, or disconnected electrode pad. Solution- correct answer - Check electrode system; re- prep and reattach electrodes and leads as necessary. Note- correct answer - A straight line may also indicate the absence of electrical activity in the heart; the patient must be evaluated immediately for the presence of a pulse. Cause- correct answer - Intermittent straight line related to ineffective contact between skin and electrode pad. Solution- correct answer - Make sure hair is clipped and electrode pad is placed on clean, dry, skin; if diaphoresis is a problem, prep skin surface with liquid adhesive, allow to dry, and reapply electrode pad. 26. Electrical interference (AC interference)- correct answer - Cause- red - left leg brown - chest 6 / 30 lectrical vements usu- tructive pul- re movements here on the er minute). correct answer - Patients using electrical equipment (electric razor, hair dryer), multiple electrical equipment in use in the room, improperly grounded equipment, loose electrical connections, or exposed wiring. Solution- correct answer - If patient is using e equipment, problem is transient and will correct itself. If patient is not using electrical equipment, unplug all equipment not in continuous use, remove from service and report any equipment with breaks or wires showing, and ask the electrical engineer to check the wiring. 27. Wandering baseline artifact- correct answer - Cause- correct answer - Exaggerated respiratory mo ally seen in patients in respiratory distress (patients with chronic obs monary disease). Solution- correct answer - Avoid placing electrode pads in areas whe of the accessory muscles are most exaggerated (which can be anyw anterior chest wall). Place the pads on the upper back if necessary. 28. Determine Regularity (Rhythm) of R Waves- correct answer - Measure from R wave to R wave across the rhythm strip, marking on the index card any variation in R wave regularity. If the rhythm varies by 0.12 second (3 small squares) or more between the shortest and longest R wave variation marked on the index card, the rhythm is irregular. If the rhythm doesn't vary or varies by less than 0.12 second, the rhythm is considered regular. 29. Calculate the Heart Rate- correct answer - Rapid rate calculation—Count the number of R waves in a 6-second strip (Figure 5.6) and multiply by 10 (6 seconds × 10 = 60 seconds, or the heart rate per minute). The R waves must be counted within the 6-second markers (some strips in this book are longer than 6 seconds). This method provides an approximate heart rate in beats per minute, is fast and simple, and can be used with both regular and irregular rhythms. If you only have a 3-second strip, count the number 7 / 30 as it leaves .04 of R waves in a 3-second strip and multiply by 20 (3 seconds × 20 = 60 seconds or the heart rate p Precise rate calculation—Count the number of small squares betwee utive R waves (Figure 5.7) and refer to the conversion table printed on the inside back cover of the book. A removable conversion table is also provided. Although this method is accurate, it can be used only for regular rhythms. If a conversion table isn't available, divide the number of small squares between the two consecutive R waves into 1,500 (the number of small squares in a 1- minute rhythm strip). The heart rates for regular rhythms in the answer keys were determined by the precise rate calculation method. 30. Irregular Rhythms- correct answer - Only rapid rate calculation is used to calculate heart rate in irregular rhythms. Count the number of R waves in a 6-second strip and multiple by 10 (Figure 5.8), or count the number of R waves in a 3-second strip and multiply by 20. 31. When rhythm strips have a premature beat- correct answer - the premature beat isn't included in the calculation of the heart rate. The premature beat is a beat from a different pacemaker site in the heart and must be assessed separately. 32. When rhythm strips have more than one rhythm on a 6-second strip- correct answer - rates must be calculated for each rhythm 33. Identify and examine the P waves- correct answer - Analyze the P waves. One P precede each QRS complex and should be identical (or near identical) in size, shape, and position 34. Measure the PR Interval- correct answer - Measure from the beginning of the P wave baseline to the beginning of the QRS complex. Count the number of small squares contained in this interval and multiply by 0 wave should 10 / 30 y 48. properties of cardiac cells- correct answer - 1. Automaticity 2. Excitability 3. Conductivity 4. Contractility Automaticity-initiate an impulse Excitability -respond to an impulse Conductivity-transmit impulses to other cells Contractility-respond to the impulse with mechanical contraction 49. 2 types of cardiac cells- correct answer - Electrical -specialized cells which conduct electrical impulses -these cells start and transmit electrical activity in the heart Mechanical -cells which make up bulk musculature in the heart -these cells contract in response to stimuli from the electrical cells 50. cardiac output- correct answer - heart rate x stroke volume 51. Stroke Volume (SV)- correct answer - The amount of blood pumped out of the heart with each contraction. 52. components of stroke volume- correct answer - preload, afterload, contractilit 53. Right Coronary Artery(RCA) perfuses the- correct answer - · RA and RV · Inferior wall of left ventricle (90%) · AV node, and the SA node (55%) 11 / 30 umflex, thus al · Bundle of His (90%) 54. Left Coronary Artery(LCA) main stem perfuses the- correct answer - Left atrio-ventricular groove Occlusion- correct answer - Lethal, results in significant “ in O2 delivery to LAD & Circ l of LV may be impacted 55. Left anterior descending artery(LAD) perfuses the- correct answer - · Anterior LV · Anterior 2/3 of septum · Apex of heart Right bundle branch(RBB) and part of the left bundle branch(LBB) Occlusion- correct answer - This may result in LV failure and conduction disturbances 56. circumflex artery perfuses the- correct answer - · Lateral wall of LV · Posterior wall of LV · Left atrium · Posterior wall of LV · SA node (45%) Occlusion- correct answer - may result in left free wall damage and formation of ventricular aneurysm 57. The best way to assess the quality of the patients mechanical function of the heart is- correct answer - Pulse and BP Pulse is the best way to assess QUALITY/Quantity of your patient's mechanical function of the heart. the primary parameter used to determine the patient's stability/unstability is the BP to identify the patient's cardiac output Occlusion: may result in bradycardias, heart blocks and RV failure pressure 12 / 30 t ventricle --> -> aortic valve ose (CO=HR X SV) 58. pulse pressure is the- correct answer - difference between systolic and diastolic 59. heart valves- correct answer - tricuspid valve, pulmonary valve, mitral valve, aortic valve 61. cardiac innervation- correct answer - The heart is under the control of the autonomic nervous system, which includes the sympathetic and parasympathetic nervous systems. Sympathetic nervous system Stimulation results in release of *norepinephrine* (a neurotransmitter), which in- creases heart rate, speeds conduction of impulses, and increases force of ventric- ular contraction. Parasympathetic nervous system Stimulation results in release of *acetylecholine* (a neurotransmitter), which de- creases heart rate, decreases conduction of impulses, and decreases force of ventricular contraction. In the normal heart, a balance is maintained between the accelerator effects of the sympathetic system and the inhibitory effects of the parasympathetic system 62. S1- correct answer - heard when the atrioventricular (mitral and tricuspid) valves cl 60. Blood flow through the heart: SVC --> Rt atria --> Tricuspid --> R Pulmonic valve --> Lungs --> Lt atria --> Mitral valve --> Lt ventricle - --> aorta --> Body 15 / 30 pulses are the - back and e electrical depolarized eats/minute hat of other hich conducts • Doppler ultrasound studies 70. Cardiac cells have four primary characteristics- correct answer - Automaticity • Ability of cardiac cells to spontaneously generate electrical impulses • Characteristic specific to pacemaker cells • Normal concentrations of sodium, potassium, and calcium are important in main- taining automaticity Excitability • Ability of cardiac cells to respond to an electrical stimulus • Characteristic shared by all cardiac cells Conductivity • Ability of cardiac cells to conduct an electrical impulse to adjacent cardiac cells • Characteristic shared by all cardiac cells Contractility • Ability of cardiac cells to cause cardiac muscle contraction • Characteristic specific to myocardial "working" cells 71. Depolarization and repolarization of cardiac cell- correct answer - Electrical im result of the flow of ions - primarily sodium (Na+) and potassium (K+) forth across the cardiac cell membrane. A series of events causes th charge inside the cell to change from its resting state (negative) to its state (positive) and back to its resting state (negative). 72. sinoatrial node (SA node)- correct answer - Located in right upper atrium • Contains pacemaker cells, which discharge impulses at 60 to 100 b • Called "pacemaker of the heart" because firing rate is higher than t pacemaker sites 73. Interatrial tract (Bachmann's bundle)- correct answer - One conduction tract, w impulse from SA node to left atrium 16 / 30 se from SA line of PR tecting ventri- ches ranch, which 74. Internodal tracts- correct answer - Three conduction tracts, which conduct impul node through right atrium to AV node 75. Atrioventricular node (AV node)- correct answer - Located in lower right upper atrium near interatrial septum • Only normal conduction pathway between atria and ventricles • Three primary functions- correct answer - - Slows conduction of electrical impulse through AV node to allow time for atrial contraction (atrial kick); delay in AV node represented on ECG as flat interval - Serves as backup pacemaker at firing rate of 40 to 60 beats/minute - Blocks rapid atrial impulses from being conducted to ventricles, pro cles from dangerously fast rates 76. Bundle of His (AV bundle)- correct answer - Connects AV node to bundle bran 77. Bundle branches- correct answer - Consist of right bundle branch and left bundle b conducts electrical impulses to the right and left ventricle 78. The heart's electrical activity is represented on the ECG tracing by three basic waveforms- correct answer -- correct answer - the P wave, the QRS complex, and the T wave (a U wave is sometimes present) Between the waveforms are segments and intervals- correct answer - PR interval, PR segment, ST segment, and QT interval 79. Cardiac cycle consists of- correct answer - one heartbeat or one PQRST sequence - One cycle represents atrial contraction and relaxation followed by 17 / 30 heir thresh- ay take ized and ventricular contraction and relaxation - This basic cycle repeats itself • Regularity of a cardiac rhythm can be measured from one heartbeat to the next (from one R wave to the next R wave, also called the R-R interval) 80. An ECG tracing provides a view of the heart's electrical activity between two poles (a positive and a negative pole).- correct answer - • Current flowing toward a positive pole produces a positive deflection • Current flowing toward a negative pole produces a negative deflection • Current flowing away from both poles will produce a biphasic deflection; biphasic deflections may be equally positive and negative, more positive than negative, or more negative than positive. 81. Refractory periods of cardiac cycle- correct answer - There is a period of time during the cardiac cycle when cardiac cells may be refractory (unable to respond) to a stimulus. Refractoriness is divided into three phases. 82. Absolute refractory period- correct answer - Cardiac cells have not repolarized to t old potential and are unable to respond to a stimulus Period extends from onset of QRS complex to peak of T wave 83. Relative refractory period- correct answer - •Cardiac cells have repolarized sufficiently to re- spond to a strong stimulus • Period extends from peak of T wave to end of T wave • Called "vulnerable period" of repolarization since a strong stimulus m possession as pacemaker of the heart 84. Supernormal period- correct answer - •Cardiac cells have almost completely repolar will respond to a weak stimulus • Period occurs near end of T wave 20 / 30 107. PR segment- correct answer - AV nodal delay - atrial kick 108. ST segment- correct answer - ventricular contraction 109. QT interval represents?- correct answer - total ventricular activity 110. Stimulation of the sympathetic nervous system results in the- correct answer - release of norepinephrine, a neurotransmitter, which accelerates the heart rate, speeds conduction through the AV node, and increases the force of ventricular contraction. 111. Stimulation of the parasympathetic nervous system results in the- correct answer - release of acetylcholine, a neurotransmitter, which slows the heart rate, decreases conduc- tion through the AV node, and causes a small decrease in the force of ventricular contraction. 112. What is the risk of an acute increase in the QT interval?- correct answer - Torsades de pointe 113. Cardiovascular surgeons perform many different types of operations- correct answer -- correct answer - - Heart valve repair and replacement Heart defect repair Coronary artery bypass Aneurysm repair Transmyocardial laser revascularization Heart transplantation Perform operations on the blood vessels in your body, including the aorta 114. Perfusionist- correct answer - Sometimes cardiac surgeons can operate on the heart when it is beating, but often they need to have it still. To maintain blood flow to the body's tissues during operations when the heart needs to be stopped, surgeons call on perfusion technologists. Perfusionists are responsible for running the heart-lung (cardiopulmonary bypass) machine. 21 / 30 The heart-lung machine diverts blood away from the heart and lungs, adds oxygen to the blood, then returns the blood to the body—all without the blood having to go through the heart. During surgery, perfusionists use the heart-lung machine to maintain blood flow to the body's tissues and regulate levels of oxygen and carbon dioxide in the blood. Perfusionists are also responsible for measuring selected laboratory values (such as blood cell count) and monitoring circulation. 115. Interventional Cardiologist- correct answer - Interventional cardiology is a subspecialty of adult cardiology dedicated to the use and application of imaging-based diagnostic techniques and minimally invasive modalities for the treatment of cardiovascular disease Cardiac Catheterization Angioplasty/Percutaneous Coronary Intervention (PCI) Stenting Embolic Protection (Filters) Percutaneous Valve Repair 116. BPG Summary of Recommendations for Collaborative Practice Amongst Nursing Teams (RNAO) 2006- correct answer - 1.1 Nurses develop knowledge about the values and behaviours that support teamwork and the impact of teamwork on patient/client safety and patient/client outcomes. 1.2 Nurses contribute to a culture that supports effective teamwork. 1.3 Nurses initiate and maintain collaborative processes within the team, especially in situations of increasing patient/client complexity, to improve patient/client out- comes. 1.4 Nursing teams establish clear processes and structures that promote collabo- ration and teamwork that leads to quality work environments and quality outcomes for patients/clients. 1.5 Nursing teams recognize how their goals contribute to, impact and/or comple- ment the goals of other teams and the organization in achieving quality patient/client care. 1.6 Nursing teams establish processes which promote open, honest and transparent channels of communication. 117. To measure the Atrial rate on the EKG you will count which of the 22 / 30 follow- ing?- correct answer - P-P/1500 118. To measure the Ventricular rate on the EKG you will count which of the following?- correct answer - R-R/1500 119. Ectopic pacemakers- correct answer - cardiac cells in areas other than the SA node may take on the role of pacemaker of the heart 120. Altered automaticity- correct answer - firing rate of the sinus node decreases, resulting in a slower sinus rate and allowing a faster ectopic site the opportunity to take control as pacemaker of the heart. • Automaticity of the ectopic site increases, resulting in a faster ectopic rate which takes control of the heart from the slower-firing SA node. 121. Triggered activity- correct answer - An electrical impulse from an ectopic site triggers the cardiac cells to depolarize more than once in response to a single stimulus. Triggered activity may result in ectopic beats or a sustained ectopic rhythm 122. Reentry- correct answer - An electrical impulse from an ectopic site depolarizes an area of the myocardium, then reenters that same area to depolarize it again. Reentry (like triggered activity) may result in ectopic beats or a sustained ectopic rhythm. 123. Atrial arrhythmias originate from- correct answer - ectopic sites in the atria 124. Wandering atrial pacemaker- correct answer - a rhythm whose pacemaker site shifts back and forth between the sinus node and multiple ectopic atrial sites, causing differences in P wave configuration. The distinguishing characteristic of this rhythm is the changing P waves, which vary in size, shape, or direction across the rhythm strip. 125. ECG features of Wandering atrial pacemaker- correct answer - rhythm - regular or irregular rate - usually normal, may be slow *P waves - vary in size, shape and direction, one p wave precedes each QRS* PR interval - usually normal but can be abnormal QRS normal 126. Facts about wandering atrial pacemaker- correct answer - In most cases, the rhythm occurs as a result of altered automaticity (either a decrease in sinus node automaticity or an increase in automaticity of the atrial pacemaker cells). 25 / 30 a saw (saw- F waves) and line between bursts of three or more beats. Three or more consecutive PACs (at a rate of 140 - 250 beats/minute) is considered to be atrial tachycardia. The P waves associated with paroxysmal atrial tachycardia are abnormal and are usually hidden in the preceding T wave, appearing as one deflection (the T-P wave). The T-P wave is a distinguishing feature of this rhythm. 137. ECG features Paroxysmal atrial tachycardia (PAT)- correct answer - 138. Facts about paroxysmal atrial tachycardia- correct answer - This rhythm may occur due to rapid firing of an ectopic atrial focus (increased automaticity of ectopic atrial cells), to triggered activity or to a reentry circuit. •PAT has been associated with ingestion of caffeine, alcohol, or tobacco; anxiety; use of drugs such as albuterol or aminophylline; chronic obstructive pulmonary disease; mitral valve disease; and digitalis toxicity. •PAT may occur in normal, healthy hearts or in those with heart disease. It is normally well tolerated in those with normal hearts 139. Treatment of paroxysmal atrial tachycardia- correct answer - Treatment is directed toward eliminating the cause, slowing the ventricular rate, and converting the rhythm. • For asymptomatic patients, sedation alone may terminate the rhythm or slow the rate, especially if anxiety is a contributing factor. Other measures include vagalma- neuvers, administration of adenosine, administration of either diltiazem or a beta blocker, and cardioversion. • Cardioversion is the initial treatment of choice for symptomatic patients. 140. Atrial flutter- correct answer - originates in an ectopic pacemaker site in the atria, depolarizing at a rate of 250 - 400 beats/minute (average rate is 300 beats/minute). At such rapid atrial rates, the AV node usually blocks at least half of the impulses to protect the ventricles from excessive rates. The AV node conducts impulses in various ratios. If the conduction ratio stays the same, the ventricular rhythm will be regular. If the conduction ratio varies, the ventricular rate will be irregular. The abnormal P waves produced in atrial flutter resemble 26 / 30 the teeth of tooth deflections). The sawtooth deflections are called flutter waves ( affect the whole baseline to such a degree that there is no isoelectric the flutter waves, and the T wave is partially or totally obscured. The distinguishing feature of atrial flutter is the sawtooth baseline between QRS complexes. 141. Comparing atrial flutter with 2- correct answer -1 AV conduction and paroxysmal atrial tachycardia (PAT)- correct answer - Atrial flutter with 2- correct answer -1 AV conduction may be difficult to differenti- ate from PAT, especially if the heart rate in both rhythms is around 150 beats/minute. These two arrhythmias can be differentiated by examining the baseline. InPAT, an isoelectric line can usually be seen after the T-Pwave. Inatrial flutter, the isoelectric line is absent 142. Facts about atrial flutter- correct answer - Chronic atrial flutter is uncommon. It usually con- verts to either atrial fibrillation or sinus rhythm spontaneously or following treatment. • This rhythm is most likely caused by a reentry circuit. • Atrial flutter is common after heart surgery. Other causes include valvular heart disease, ischemic heart disease, pulmonary embolism, and alcohol intoxication. Potential dangers • There may be a decrease in cardiac output if ventricular rate is rapid. • Mural thrombi may form due to ineffective atrial contractions and blood stasis, leading to a risk of systemic or pulmonary emboli. 143. Treatment of atrial flutter- correct answer - Treatment is directed toward controlling the ventric- ular rate, anticoagulation, and restoring sinus rhythm. • Controlling the ventricular rate should be attempted first using either diltiazem or a beta blocker. If the rhythm has been present less than 48 hours, it is safe to convert the rhythm with amiodarone or cardioversion. If the rhythm has been present greater than 48 hours, the patient should be anticoagulated and a transesophagealechocar- diogram (TEE) 27 / 30 performed to check for mural thrombi prior to conversion attempts. Symptomatic atrial flutter is treated with cardioversion regardless of the duration of the rhythm. • Radiofrequency catheter ablation of the flutter reentry circuit is becoming the treatment of choice for chronic or recurrent atrial flutter. 144. Atrial fibrillation- correct answer - is a rapid and highly irregular heart rhythm originating in an ectopic site in the atria, depolarizing at a rate greater than 400 beats/minute. As in atrial flutter, the AV node blocks most of the impulses from entering the ventricles, thus protecting the ventricles from excessive rates. The AV node conducts impulses irregularly, resulting in an irregular ventricular rhythm. When the ventricular rate is less than 100 beats/minute, the rhythm is called controlled atrial fibrillation.When the ventricular rate is greater than 100 beats/minute, the rhythm is called uncontrolled atrial fibrillation. The ventricular rhythm is more irregular with slower rates and less irregular with faster rates. The atrial impulses are so rapid in atrial fibrillation that they cause the atria to quiver instead of contract regularly, producing irregular, wavy deflections called fibrillatory waves(f waves). The fibrillatory waves affect the whole baseline. An atrial rate is not measurable. Flutter waves are sometimes seen mixed with the fibrillatory waves. This mixed rhythm is often called atrial fib-flutter,meaning the basic rhythm is atrial fibrillation with some flutter waves present. The distinguishing feature of atrial fibrillation is the wavy baseline between QRS complexes. 145. ECG features Atrial fibrillation- correct answer - 146. Facts about atrial fibrillation- correct answer - Atrial fibrillation is the most common rhythm seen next to normal sinus rhythm (NSR). • The mechanism of this rhythm is most likely a reentry circuit. • Atrial fibrillation is common after heart surgery. Other causes include valvularheart disease, coronary heart disease, hypertension, congestive 30 / 30 blood flow to the AV node; and digitalis toxicity 153. Treatment of PJCs- correct answer - •Infrequent PJCs require no treatment. • Frequent PJCs are treated by correcting the underlying cause 154. junctional escape beat- correct answer - A junctional ectopic beat that occurs late instead of early is called a junctional escape beat. The morphological characteristics of the late beat are the same as with the PJC. Junctional escape beats usually occur during a pause in the underlying rhythm. Escape beats act as an electrical backup to maintain the heart rate and require no treatment. 155. Junctional rhythm- correct answer - originates in an ectopic pacemaker site in the AV junction at a rate of 40 to 60 beats/minute. It occurs as a regular, continuous rhythm and is characterized by an inverted P wave that may occur before the QRS, after the QRS, or be hidden within the QRS complex; a short PRinterval of 0.10 second or less; and a normal QRS complex. 156. Facts about junctional rhythm- correct answer - •Junctional rhythm is not a common arrhyth- mia. •Junctional rhythm is the normal rhythm of the AV junction. • Junctional rhythm usually occurs when the rate of the sinus rhythm drops below the normal inherent rate of the AV junctional pacemaker. • Conditions associated with junctional rhythm include inferior wall MI and digitalis toxicity. • Junctional rhythm has the same identifying features as accelerated junctional rhythm and junctional tachycardia. The rhythms are differentiated by the heart rate. 157. Treatment of junctional rhythm- correct answer - •The rhythm rarely requires treatment unless the rate is too slow to maintain cardiac output. • If the rate is slow and the patient is symptomatic, atropine can be given to increase the sinus rate and override the junctional focus. Pacing may become necessary. • Treatment should also be directed toward identifying and correcting the underlying cause. 158. Accelerated junctional rhythm- correct answer - originates in an 31 / 30 ectopic pacemaker site in the AV junction at a rate of 60 to 100 beats/minute. The term accelerated denotes a rhythm that occurs at a rate faster than the inherent junctional rate of 40 to 60 beats/minute, but that isn't fast enough to be junctional tachycardia. Accelerated junctional rhythm is a regular, continuous rhythm characterized by an inverted P wave that may occur before the QRS, after the QRS, or be hidden within the QRS complex; a short PR interval of 0.10 second or less; and a normal QRS complex. 159. ECG Features Accelerated junctional rhythm- correct answer - 160. Facts about accelerated junctional rhythm- correct answer - •Accelerated junctional rhythm is not a common arrhythmia. • The mechanism responsible for this rhythm is most likely enhanced automaticity of the AV junction. • Accelerated junctional rhythm has the same identifying features as junctional rhythm and junctional tachycardia. The rhythms are differentiated by the heart rate. 161. Treatment of accelerated junctional rhythm- correct answer - •A reduction in cardiac output may be present due to the retrograde depolarization of the atria with subsequent loss of the atrial kick. Treatment is directed toward reversing the consequences of reduced cardiac output. • Identify and correct the underlying cause of the arrhythmia. 162. Atrial flutter is easily identified by the- correct answer - sawtooth baseline 163. atrial kick- correct answer - - additional volume of blood in ventricles causes by atrial systole -accounts for 5-30% of cardiac output 164. Facts about sinus bradycardia- correct answer - 1Normal response of heart in certain circum- stances (for example relaxation, sleep) • Most common arrhythmia associated with acute inferior wall myocardial infarction 32 / 30 es) • Other causes- correct answer - Reperfusion rhythm following myocardial reperfusion procedures (thrombolytic administration, angioplasty); vagal stimulation; sleep apnea; hyper- kalemia; increased intracranial pressure; disease of SA node; and administration of drugs, such as digitalis, calcium channel blockers, and beta blockers • Persistent bradycardia may result in decreased cardiac output due to a decrease in heart rate. Cardiac output = stroke volume ×heart rate. A decrease in either stroke volume or heart rate may result in a decrease in cardiac output. 165. Sinus arrhythmia occurs when- correct answer - he sinus node discharges impulses irregu- larly. The heart rate may be normal range or slow. All other parameters are normal. 166. Sinus arrhythmia ECG- correct answer - irregular rhythm rate normal or slow P waves normal PR interval normal 0.12 to 0.20 QRS normal less than 0.1 167. Blood pressure in arteries is higher than- correct answer - blood pressure in veins 168. cardiovascular system- correct answer - systemic circuit pulmonary circuit 169. Anatomy of the heart- correct answer - Large, muscular organ consisting of mostly cardiac tissue called the myocardium Surrounded by a sac called the pericardium Consists of 2 sides, right and left, separated by a septum Consists of 4 chambers- correct answer - 2 atria and 2 ventricles 2 sets of valves- correct answer - semilunar valves and 35 / 30 square = 0.02 181. Waveforms and the isoelectric line- correct answer - Between cardiac cycles, the ECG records a straight line (isoelectricline or baseline) Any waveform above baseline is considered a positive deflection; a waveform below baseline is considered a negative deflection; a waveform that is both above and below baseline is considered a biphasic deflection 182. ECG graph paper- correct answer - waveforms are recorded on graph paper containing hori- zontal and vertical lines. The lines are used to measure width and height of deflec- tions. Width • Horizontal lines are used to measure duration (width) of waveforms in seconds of time • Each small square measured horizontally measures 0.04 second (½ second) QRS width of 2 squares = 0.08 second (0.04 second × 2 squares) Height • Vertical lines are used to measure height (amplitude or voltage) of a waveform • Each square measured vertically from baseline measures 1 millimeter (mm) in height • QRS extending upward from baseline 16 small squares = 16 mm voltage (1 mm ×16 squares) 183. blood pressure- correct answer - Pressure exerted by the blood upon the walls of the blood vessels, especially arteries, usually measured by means of a sphygmomanometer and expressed in millimeters of mercury. 184. preload- correct answer - volume of blood in ventricles at end of diastole 36 / 30 (left) ventricle cle. In 90% of e left ventricle, f hearts, it ches AV node and 185. afterload- correct answer - the amount of resistance to ejection of blood from the - amount of resistance to overcome 186. U wave- correct answer - if visible, typically follows the T wave 187. sinus rhythm- correct answer - normal heartbeat triggered by the SA node 188. a cardiac cycle on ecg is- correct answer - PQRST 189. test outline - Chapter 1 function, structure, layers, circulatory, blood flow, valves, s1, s2, coronary circulation, coronary arteries, innervation, pns, sns, neurotransmitters Chapter 2 - cardiac cells, properties, depolarization, polarization,- correct answer - 190. Right coronary artery supplies- correct answer - right atrium and the right ventri individuals, the right coronary artery also supplies the inferior wall of th the posterior one- third of the interventricular septum, the AV node, and the bundle of His. In 55% o supplies the SA node. 191. left coronary artery supplies- correct answer - divides into the LAD and Circumflex LAD- correct answer - left ventricle, interventricular septum, right and left bundle bran Circumflex- correct answer - left atrium, left ventricle, interventricular septum, SA node, bundle of his. 37 / 30 192. There are two basic kinds of cardiac cells in the heart- correct answer - the myocardial muscle cells (or working cells) and the myocardial pacemaker cells. 193. Telemetry lead placement- correct answer - 194. ST depression- correct answer -