RCES Exam Extended Questions with All Correct Answers

What is ARVD and when does it occur? Arrhythmogenic Right Ventricular dysplasia; occurs when the RV myocardium is replaced by fatty and fibrotic tissue What are afterdepolarizations? Abnormal secondary voltage depolarizations during the cardiac action potential What are the two types of afterdepolarizations? EADs (early after depolarizations) and DADs (delayed afterdepolarizations What does the QT interval represent? ventricular depolarization and repolarization What is antedromic conduction? Antedromic conduction is a type of AVRT in which the impulse travels down the pathway and up the AV node--seen in WPW What is orthodromic conduction? A type of AVRT in which the impulse travels down the AV node and up the pathway--this type of conduction is more common What 3 criteria are needed to sustain a reentry circuit? 1.) Parallel pathways that are connected proximally and distally, forming an electrical circuit 2.) One of the pathways needs a refractory period that's substantially longer than the refractory period of the other 3.) The pathway with the shorter refractory period must conduct electrical impulse more slowly than the other pathway What is a normal AH interval? 50-140ms What is a normal HV interval? 35-55ms What is a normal HBE? <30ms What is a normal PA interval? 25-55ms What is a normal QTc? For men: <450, For women <470 What is a normal QRS interval? <120ms What is Ohm's Law? V = IR; V= voltage measured in volts, I= current measured in amps and R= resistance ohms What is the most likely rhythm is capture beats or fusion beats are seen on the EKG? Ventricular Tachycardia because both beats demonstrate AV dissociation When do EADs occur? EADs are seen in phase 2 or phase 3 of the action potential What is the formula for converting Fahrenheit to Celsius? C= (5/9) (F-32) What is the formula for converting Celsius to Fahrenheit? F= (9/5)C +32 What is the formula for calculating HR? 60,000msec/ RR What is the most common location of outflow tract VT? RVOT What is a bystander pathway? An associate pathway that is passively activated BUT it is not in the tachycardia circuit If VT originates in the LV, there will be a _____________________ morphology? Right Bundle Branch Block (positive in lead V1) What would be the result of ablating a bystander pathway? Blocking the bystander pathway would not terminate the arrhythmia What is precordial concordance? When the appearance of the QRS complexes in leads V1-V6 are either all negative or all positive *** this finding on an ECG is diagnostic of VT What is Naxos disease? Has symptoms of ARVD (myocardium is replaced for fatty tissue) as well as an association of diffuse palmoplantar keratoderma and thick wooly hair What does a completely negative LBBB appearance on lead V1 indicate? It indicates that the VT is originating from the RV What are the Class I AADs Sodium Channel Blockers What are the Class Ia AADs? Quinidine, Procainamide, Disopyramide (Norpace) Where is the tricuspid valve located? Between the RA and RV; it has 3 leaflets What are the AV valves? tricuspid and mitral; they are open during ventricular systole Where is the mitral valve located? between left atrium and left ventricle What are the semilunar valves? pulmonary and aortic; open during ventricular systole Where is the pulmonic valve located? Its located on the right side of the heart and is between the right ventricle and the pulmonary artery Where is the aortic valve located? Its located on the left side of the heart and is between left ventricle and aorta What is the most anterior chamber of the heart? The right ventricle; tissue is thicker than that of the right atrium because it pumps blood to the lungs What is the most anterior cardiac valve? The pulmonic valve; its close to the sternum Where is the foramen ovale located? Its located on the septal wall of the right atrium Where is the coronary sinus located? Its located near the floor of the right atrium and allows blood to flow from the cardiac muscle back to the right atrium What is the eustachian ridge? its a remnant of the eustachian valve (valve of the IVC) and is located posterior to the CS on the floor of the right atrium What is the right atrial appendage? A common site for placement of atrial leads in pacemakers and defibrillators, located anteriorly and superiorly (superior to the fossa ovalis Where is the crista terminalis? Its located on the open flap of the right atrium, runs from high septum, anterior to the orifice of the SVC superiorly and courses caudally along posterior lateral aspect of the RA The irregular bands of tissue projecting from the inner surfaces of the ventricles are called Trabeculae carnea What is the moderator band? The largest of the trabeculae carnea that connects the lateral wall of the right ventricle to the intraventricular septum; it also houses part of the right bundle branch What is the most posterior chamber of the heart? left atrium; it contains the foramen ovale and the pulmonary veins Where is the SA node located? located at the junction of the superior vena cava and the right atrium What is Bachmann's bundle? Its a band of tissue that carries electrical impulses from the right atrium to left atrium