1、 cardiology2016 81-90Q 1A 68-year-old Caucasian male presents to your office complaining of fatigue and difficulty carrying out his normal daily activities. He has a history of hypertension, type 2 diabetes mellitus, and osteoarthritis. He has smoked one pack of cigarettes per day for the past 40 ye
2、ars Which of the following would most likely indicate left-sided heart failure in this patient?A. Wheezing on moderate exertion B. Chest tightness on moderate exertion C. Supine dyspnea that is relieved by sitting up D. Symmetric lower extremity edema E. Fullness and tenderness over right subcostal
3、area F. Paroxysmal cough relieved by sputum productionA 1 Correct answer:CThe most prominent extracardiac effects of left-sided heart failure occur in the lungs. The increased left ventricular filling pressures required to maintain an adequate stroke volume are reflected back to the left atrium and
4、pulmonary veins. Pulmonary venous hypertension produces pulmonary interstitial edema in interlobular septa, edematous widening of alveolar septa, and finally intra-alveolar accumulation of edema fluid. There is a corresponding progressive impairment in pulmonary gas exchange Supine dyspnea that is r
5、elieved by sitting up. known as orthopnea, is a relatively specific sign of advanced left-sided heart failure. It results from an acute exacerbation of baseline pulmonary edema that occurs when central venous, pulmonary venous, and cardiac filling pressures are increased by the redistribution of blo
6、od that had been pooled in dependent veins back into the central circulation. Pulmonary edema resulting in orthopnea can be seen in the absence of left ventricular dysfunction in patients with mitral stenosis.(Choice A) Wheezing on exertion may occur in left-sided heart failure (cardiac asthma), but
7、 this finding is nonspecific. Cardiac asthma occurs because exercise increases venous return to the heart, but the failing left ventricle is unable to sufficiently increase cardiac output to prevent a significant exercise-induced increase in pulmonary venous pressure. Exertional wheezing may also oc
8、cur in asthma and chronic obstructive pulmonary disease(Choice B) Chest tightness on moderate exertion is a nonspecific symptom that might be seen in left-sided heart failure as a result of cardiac asthma. However, exertional tightness is more commonly a symptom of exercise-induced asthma due to non
9、cardiac causes. This symptom may also be due to coronary artery disease (angina).(Choice D) Bilateral lower extremity edema could be medication induced (e.g., calcium channel blockers) or due to right-sided heart failure, cirrhosis of the liver, or inferior vena cava obstruction. Although right-side
10、d heart failure is most commonly a consequence of left-sided heart failure, isolated right-sided failure can occur in patients with cor pulmonale, idiopathic pulmonary hypertension, right ventricular infarction, etc.(Choice E) Liver fullness is present in congestive hepatomegaly associated with righ
11、t-sided heart failure.(Choice F) Paroxysmal cough relieved by sputum production is a nonspecific symptom, with several potential causes. Pink frothy sputum can be seen in patients with left ventricular failure, or other causes of severe pulmonary edema, and is due to rnpture of bronchial veins. Any
12、infectious (e g. bronchitis) or inflammatory (e g. asthma) condition associated with bronchial exudation could cause paroxysmal cough relieved with sputum production as well.Educational Objective:Orthopnea is a quite specific sign of left-sided heart failure. Bilateral lower extremity edema and cong
13、estive hepatomegaly are more specific for right-sided heart failure. Left-sided heart failure may also produce a productive cough and exertional wheezing or chest tightness, but these are nonspecific signs seen in a variety of disorders.Q 2The following vignette applies to the next 2 Items. The item
14、s in the set must be answered in sequential order. Once you click Proceed to Next Item, you will not be able to add or change an answer.A 53-year-old man comes to the emergency department due to fever and progressive weakness over the last 2 weeks. Yesterday, he also developed shortness of breath. T
15、he patient emigrated from Eastern Europe 2 years ago andsays he was diagnosed with “heart disease“ in the distant past, but he does not recall Uany details. He does not use tobacco, alcohol, or illicit drugs. Despite receivingappropriate medical care, the patient expires during hospitalization. On a
16、utopsy,gross examination of his heart shows large, friable masses on the mitral valve withextensive destruction of cuspal tissue.Item 1 of 2Which of the following is the most likely predisposing factor for this patients presenting condition?A. Myocardial hypertrophy B Myocardial thinning and fibrosi
17、s C. Pericardial effusion D. Rupture of chordae tendineae E. Valvular inflammation and scarringA 2Correct answer:EThis patients presentation - fever, progressive weakness, and dyspnea (due to valvular regurgitation) - along with the presence of vegetations on the mitral valve is consistent with infe
18、ctive endocarditis (IE). Predisposing factors for IE include valvular abnormalities (eg, rheumatic heart disease, mitral valve prolapse, prosthetic valves, congenital heart disease) and conditions that promote bacteremia/fungemia (eg, intravenous drug use, dental procedures).This patient likely had
19、a remote history of rheumatic heart disease (immigrant from developing region, history of heart disease) with underlying degeneration of the mitral valve due to chronic valvular inflammation and scarring(Choice A) Myocardial hypertrophy is seen in patients with uncontrolled hypertension, aortic sten
20、osis, and hypertrophic cardiomyopathy and, in general, does not predispose to IE.(Choice B) Myocardial fibrosis is associated with infiltrative cardiomyopathy (sarcoidosis, amyloidosis), Chagas disease, myocarditis, and prior myocardial infarction. It does not lead to increased risk of IE.(Choice C)
21、 Pericardial effusion occurs as a result of inflammation of the pericardium (acute or chronic pericarditis) and has no association with the risk of IE.(Choice D) Rupture of chordae tendineae is a complication of endocarditis or myocardial infarction; it is not a risk factor for development of IE.Edu
22、cational objective:Chronic valvular inflammation and scarring associated with rheumatic heart disease predispose to an increased risk of infective endocarditis, which is characterized by valvular vegetations with destruction of the underlying cardiac tissue.Q 3The blood cultures obtained from this p
23、atient on admission grow Streptococcus species. Which of the following processes was the most likely initiating step in the pathogenesis of this patients condition?A. Endocardial fibrosis B. Fibrin deposition C. Liquefactive necrosis D. Myxomatous degeneration E. White blood cell infiltrationA 3Corr
24、ect answer:BThe initial process involved in the pathogenesis of infective endocarditis (IE) is a disruption of normal endocardial surface. This occurs most commonly at the areas of maximal turbulence to blood flow in preexisting valvular lesions, typically the atrial surface of incompetent atriovent
25、ricular valves or the ventricular surface of incompetent semilunar valves. This is followed by focal adherence of fibrin and platelets, forming a sterile fibrin-platelet nidusDuring bacteremia from any cause, microorganisms colonize the sterile nidus on the endothelial surface with subsequent microb
26、ial growth leading to further activation of the coagulation system. Streptococci infect the cardiac valves with preexisting endothelial lesions. In contrast, Staphylococcus aureus can adhere to damaged or normal endothelial cells. Macroscopic vegetations consist of fibrin and platelets on the surfac
27、e, with red blood cell debris, leukocytes, and clusters of microorganisms embedded deep within the lesion.(Choice A) Endomyocardial fibrosis is a restrictive cardiomyopathy characterized by thickening and fibrosis of the apical endocardial surface. It occurs most commonly in tropical regions (eg, Ug
28、anda).(Choices C and E) Neutrophil-rich inflammatory infiltrates with subsequent abscess formation and/or liquefactive necrosis of underlying cardiac tissue are common in advanced lesions.(Choice D) Myxomatous degeneration of the mitral valve is characterized by thickened and redundant mitral leafle
29、ts with elongated chordae leading to prolapse of one or both mitral leaflets (mitral valve prolapse). Myxomatous degeneration can predispose patients to the development of endocarditis; however, endocarditis vegetations themselves are not formed through myxomatous degeneration.Educational objective:
30、Vegetations are caused by bacterial colonization and growth on a sterile fibrin-platelet nidus that forms on the damaged/disrupted endothelial surface of the valvular apparatus.Q 4A 34-year-old Asian female is hospitalized with progressive exertional dyspnea, lower extremity edema and cough. She als
31、o describes frequent nocturnal episodes of breathlessness and recent hoarseness. She does not use tobacco, alcohol or drugs. Auscultation reveals loud first and second heart sounds and a mid-diastolic rumble best heard at the cardiac apex. This patients hoarseness is most likely caused by:A. Larynge
32、al edema B. Impaired arterial supply C. Nerve impingement D. Epithelial sloughing E. Vocal cord polypsA 4Correct answer:CIn rare instances, the left recurrent laryngeal nerve may be compressed to the point of neurapraxia (failure of nerve conduction due to blunt injury) by enlargement of the left at
33、rium and/or other structures in the vicinity of its course as it loops behind the ligamentum arteriosum, underneath and around the aortic arch, and back up alongside the trachea to the larynx. Mitral stenosis can cause left atrial dilatation sufficient to impinge on the left recurrent laryngeal nerv
34、e (Ortner syndrome).The recurrent laryngeal nerves innervate all of the intrinsic muscles of the larynx except the cricothyroid muscle Paresis of vocal cord muscles innervated by left recurrent laryngeal nerve can cause hoarseness.(Choice A) Laryngeal edema can cause hoarseness but is commonly due t
35、o direct laryngeal inflammation (e g. by an upper respiratory infection).(Choice B) Vascular disease or injury resulting in ischemia of the vocal cords, the recurrent laryngeal nerves, and/or the vagal motor nuclei in the brain stem could result in laryngeal neuromuscular dysfunction, producing hoar
36、seness. However, the patients hist f7 and presentation make MS a more likely culprit.(Choice D) Hoarseness is predominantly due to vocal cord disease (including mucosal inflammation or edema) or vocal cord malfunction. Epithelial sloughing could be associated with laryngeal mucosal disease and might
37、 be seen in asthma or airway exposure to noxious external gases or gastric acid. However, the other components of the patients history and physical make severe MS more likely as an underlying pathogenic factor.(Choice E) Vocal cord epithelial or mucosal polyps can also cause hoarseness, but are less
38、 likely etiologies here, given the patients history.Educational Objective:Left atrial enlargement can sometimes cause left recurrent laryngeal nerve impingement. Neurapraxia resulting in left vocal cord paresis and hoarseness may result.Q 5A 34-year-old Asian female is hospitalized with progressive
39、exertional dyspnea, lower extremity edema and cough. She also describes frequent nocturnal episodes of breathlessness and recent hoarseness. She does not use tobacco, alcohol or drugs. Auscultation reveals loud first and second heart sounds and a mid-diastolic rumble best heard at the cardiac apex. This patients hoarseness is most likely caused by:A. Laryngeal edema B. Impaired arterial supply C. Nerve impingement D. Epithelial sloughing E. Vocal cord polyps
