CV practice test questions And answers 2022

arteriography of a patient's left renal artery shows narrowing of the radius of the artery by 50%, what is the expected change in blood flow through the stenotic artery? It will decrease to 1/16 of it's original flow. When a person moves from a supine position to a standing position, which of the following compensatory changes occurs? Increased heart rate, and increased contractility at which site is systolic blood pressure the highest? the renal artery a person's ECG has no P wave but has a normal QRS complex and a normal T wave, therefore, his pacemaker is located in the atrioventricular node (AV) if the ejction fraction increases there will be a decrease in: the end-systolic volume In an ECG on a person shows ventricular extrasystoles, the extrasystolic beat would produce decreased pulse pressure because stroke volume is decreased an ECG on a person shows ventricular extrasystoles, the next "normal ventricular contraction that occurs after the extrasystole would produce: increased pulse pressure because the contractility of the ventricle is increased and increase in contractility is demonstrated on a frank-starling diagram by increase cardiac output for a given end-diastolic volume on the graph showing left ventricular volume and pressure, isovolumetric contraction occurs from point; 1>2 the aortic valve closes at point : 3 the first heart sound corresponds to poin 1 if the heart rate is 70bpm then the cardiac output of this ventricle is closest to 5.25L/min in a capillary, P(c) is 30 mm Hg, P(1) is 2mm Hg, x(c) is 25mm Hg, and x(1) is 2mm Hg, what is the direction of fluid movement and the net driving force? filtration a 9mm Hg in a capillary, P(c) is 30 mm Hg, P(1) is 2mm Hg, x(c) is 25mm Hg, and x(1) is 2mm Hg, if K(t) is 0.5mL/min/mm Hg, what is the rate of water flow across the capillary wall? 4.50mL/min the tendency for blood flow to be turbulent is increased by partial occlusion of a blood vessel a patient experiences orthostatic hypotension after a sympathectomy, the explanation for this occurrence is a suppressed response of the baroreceptor mechanism the ventricles are completely depolarized during which isoelectric portion of the ECG? ST segment in which of the following situations is pulmonary blood flow greater than aortic blood flow? left to right ventricular shunt the change indicatied by the dashed lines on the cardiac output/neous return curves shows increased mean systemic pressure a person's ECG show two p waves preceding each QRS complex, the interpretation of this pattern is decreased conduction through the AV node an acute decrease in arterial blood pressure elicits which of the following compensatory changes? decreased firing rate of the carotid sinus nerve the tendency for edema to occur will be increased by increased venous pressure inspiration "splits" the second heart sound because the aortic valve closes before the pulmonic valve during exercise tatal peripheral resistance (TPR) decreases because of the effect of local metabolites on skeletal muscle aterioles an increase in arteriolar resistance without a change in any other component of the cv system will produce an increase in arterial pressure the following measurments were obtained in a male patient: HR 70 pulmonary vein O2= .24mL O2/mL pulmonary artery O2= .16 mL O2/mL whole body O2 consumption = 500mL What is this patient's cardiac output? 6.25 L/min which of the following is the result of an inward Na+ current? upstroke of the action potential in Purkinje fibers the greatest pressure decrease in the circulation occurs across the arterioes because they have the greatest resistance pulse pressure is determined by stroke volume in the sinoatrial node phase 4 depolarization (pacemaker potential) is attributable to an increase in Na+ cunductance which receptor mediates constriction of arteriolar smooth muscle? alpha 1 receptors during which phase of the cardiac cycle is aortic pressure highest? reduced ventricular ejection myocardial contractility is best correlated with the intracellular concentration of Ca2+ which of the following is an effect of histamine? vasodilation of the arterioles carbon dioxide regulates blood flow to which one of the following organs? brain cardiac output on the right side of the heart is what percentage of the cardiac output of the left side of the heart? 100% the physiological function of the relatively slow conduction through the atrioventricular node is to allow sufficient time for filling of the ventricles blood flow to which organ is controlled primarily by the sympathetic nervous system rather than by local metabolites? skin which of the following parameters is decreased during moderate exercise? total peripheral resistance (TPR) when propranolol is administered, blockade of which receptor is responsible for the decrease in cardiac output that occurs? it inhibits Beta 1 receptors in the SA node(HR) and in ventricular muscle during which phase of the cardiac cycle is ventricular volume lowest? isovolumetric ventricular relaxation which of the following chages will cause an increase in myocardial O2 consumption? increased size of the heart which of the following substaces crosses capillary walls primarily through water-filled clefts between the endothelial cells? glucose a 24 year old woman presents to the er with sever diarrhea, when she is supine her bp is 90/60, and her HR is 100 bpm, when she is moved to a standing position her HR further increases to 120 bpm, which of the following accounts for the further increase in HR upon standing? decreased venous return a 60 year old businessman is evaluated by his physician who determines that his bp is significantly elevated at 185/130, lab tests reveal an increase in plasma renin activity, plasma aldosterone levels, and left renal vein renin levels, his right renal vein renin level is decreased, what is the most liekly cause of the pt's HTN? left renal artery stenosis