內(nèi)科學(xué)教學(xué)課件：感染性心內(nèi)膜炎、心瓣膜病

1、Infective Endocarditis Infective endocarditis (IE) is a microbial infection of the endothelial surface of the heart. Acute IE Subacute IE Definition The characteristic lesion-IE The vegetation, is a variably sized amorphous mass of platelets and fibrin in which abundant microorganisms and moderate i

2、nflammatory cells are enmeshed. Acute IE Acute IE arises with marked toxicity progresses over days to several weeks to valvular destruction and metastatic infection. Acute IE is caused typically, although not exclusively, by Staphylococcus aureus (金金 黃色葡萄球菌黃色葡萄球菌). Subacute IE Subacute IE evolves ov

3、er weeks to months with only modest toxicity and rarely causes metastatic infection. Subacute IE is more likely to be caused by viridans streptococci (綠色鏈球菌), enterococci(腸球菌), or gram-negative coccobacilli(球桿菌). Predisposing Conditions in Adult Rheumatic heart disease (25-30%) Congenital heart dise

4、ase (10-20%) Mitral valve prolapse (10-30%) Degenerative heart disease(30% in elderly) Parenteral(腸胃外的)drug abuse (15-35%) Other (10-15%) None (25-45%) Pathogenesis Development of nonbacterial thrombotic endocarditis(NBTE). Two major mechanisms appear pivotal in the formation of NBTE: endothelial in

5、jury and a hypercoagulable state. Pathogenesis Development of nonbacterial thrombotic endocarditis(NBTE). Three hemodynamic circumstances may injure the endothelium, initiating NBTE: (1) a high-velocity jet striking endothelium, (2) flow from a high- to a low-pressure chamber, and (3) flow across a

6、narrow orifice at high velocity. Pathogenesis Conversion of NBTE to infective endocarditis. Pathophysiology Local destructive effects of intracardiac infection Embolization of septic fragments of vegetations to distant sites, resulting in infarction or infection Hematogenous seeding of remote sites

7、during continuous bacteremia Pathophysiology Antibody response -The infecting organism with subsequent tissue injury caused by deposition of preformed immune complexes or antibody-complement interaction with antigens deposited in tissues. Pathophysiology NBTE Conversion of NBTE to IE Embolization An

8、tibody response Subacute Infective Endocarditia 常在風(fēng)濕性心內(nèi)膜炎基礎(chǔ)上合并較弱的草綠色鏈球菌感染。主動脈瓣的常在風(fēng)濕性心內(nèi)膜炎基礎(chǔ)上合并較弱的草綠色鏈球菌感染。主動脈瓣的 兩兩 個瓣膜上淺褐色贅生物附著（個瓣膜上淺褐色贅生物附著（），瓣膜結(jié)構(gòu)破壞。），瓣膜結(jié)構(gòu)破壞。 Acute Infective Endocarditis 二尖瓣心房面粉紅色贅生物形成（二尖瓣心房面粉紅色贅生物形成（），部分脫落），部分脫落 形成潰瘍。形成潰瘍。 AIE 多由毒力較強的多由毒力較強的 化膿菌引起正常心化膿菌引起正常心 內(nèi)膜的炎癥。內(nèi)膜的炎癥。 1. 1.瓣膜壞死

9、，大瓣膜壞死，大 量藍染細菌散落在量藍染細菌散落在 壞死組織中壞死組織中. . 2. 2.中性粒細胞浸中性粒細胞浸 潤。潤。 3. 3.共同形成贅生共同形成贅生 物。物。 4. 4.贅生物脫落。贅生物脫落。 Clinical Features Fever Heart murmurs Enlargement of the spleen Systemic emboli Neurological symptoms Petechiae,Splinter or subungual hemorrhages,Osler nodes Others Clinical Features- Fever The mo

10、st common symptom and sign in patients with IE. Clinical Features- Heart murmurs Noted in 80-85% of patents with native valve endocarditis (NVE). The new or changing murmurs are relatively infrequent in subacute NVE and are more prevalent in acute IE and prosthetic valve endocarditis (PVE). Clinical

11、 Features Enlarge- of spleen Common in subacute IE of long duration. Clinical Features -Systemic emboli Musculoskeletal symptoms - arthralgias(關(guān)節(jié)痛) and myalgias(肌 痛) Renal,Cerebral,Artery Clinical Features- Neurological symptoms Embolic stroke Intracranial hemorrhage Aneurysms(動脈瘤), Cerebritis(大腦炎),

12、 Purulent meningitis(化膿性腦膜 炎). Clinical Features- Petechiae(淤點) Petechiae(淤點) Splinter or subungual(指甲下 的 )hemorrhages Osler nodes Clinical Features- Others Renal insufficiency as a result of immune complex-mediated glomerulonephritis. A. Splinter hemorrhage B. Conjunctival patechiae C. Osler node D

13、. Janeways lesion *Early PVE: often lake of peripheral vascular lesions 右邊的感染性心內(nèi)膜炎患者手指，上面有小塊右邊的感染性心內(nèi)膜炎患者手指，上面有小塊 裂片形出血，出血位于指甲下，呈線性暗紅色條紋裂片形出血，出血位于指甲下，呈線性暗紅色條紋 類似的出血還可見于外傷。類似的出血還可見于外傷。 感染性心內(nèi)膜炎患者左手大拇指的指甲下可見另一感染性心內(nèi)膜炎患者左手大拇指的指甲下可見另一 個小的呈線型的裂片形出血，血培養(yǎng)為金黃色葡萄球菌個小的呈線型的裂片形出血，血培養(yǎng)為金黃色葡萄球菌 陽性。陽性。 Clinical and Lab

14、oratory Data Echocardiography. Establishing the microbial cause Obtaining blood cultures Clinical and Laboratory Data - Echocardiography Detect vegetations in patients if mutiplanar TEE and TTE are combined. 二維超聲二維超聲 左室長軸左室長軸 切面示二切面示二 尖瓣附著尖瓣附著 之贅生物之贅生物 隨瓣葉活隨瓣葉活 動，舒張動，舒張 期隨瓣葉期隨瓣葉 開放活動開放活動 至左室。至左室。 Cl

15、inical and Laboratory Data Establishing the microbial cause A microbial cause of IE is established by recovering the infecting agent from the blood or by identifying it in surgically removed vegetations or embolic material. Clinical and Laboratory Data Obtaining blood cultures Three separate sets of

16、 blood cultures, each from a separate venipuncture, obtained over 24 hours. Recommended to evaluate patients with suspected endocarditis. Clinical and Laboratory Data Obtaining blood cultures Each set should include two flasks, one containing an aerobic medium and the other containing anaerobic （厭氧的

17、）medium, into each of which at least 10 ml of blood should be placed. Diagnosis Diagnosis of IE(Modified Duke Critera) Definitive Infective Endocarditis Pathological criteria Microorganisms: demonstrated by culture or histology in a vegetation, or in a vegetation that has embolized, or in an intraca

18、rdiac abscess Diagnosis of IE(Modified Duke Critera) Definitive Infective Endocarditis Pathological criteria Pathological lesions: vegetation of intracardiac abscess present, confirmed by histology showing active endocarditis Diagnosis of IE(Modified Duke Critera) Definitive Infective Endocarditis C

19、linical criteria, using specific definitions listed below Two major criteria, or One major and three minor criteria, or Five minor criteria Diagnosis of IE(Modified Duke Critera) Possible Infective Endocarditis One major criterion and one minor criterion Three minor criteria Diagnosis of IE(Modified

20、 Duke Critera) Rejected 1.Firm alternative diagnosis for manifestations of endocarditis, or 2.Sustained resolution of manifestations of endocarditis, with antibiotic therapy for 4 days or less, or 3.No pathological evidence of infective endocarditis at surgery or autopsy, after antibiotic therapy fo

21、r 4 days or less Diagnosis of IE(Modified Duke Critera) Criteria for Diagnosis of Infective Endocarditis Major criteria 1. Positive blood culture- Persistently Typical microorganism for infective endocarditis from two separate blood culture ( Viridans streptococci, Streptococcus boris, HACEK group o

22、r Staphylococcus aureus or community-acquired enterococci in the absence of a primary focus.) Diagnosis of IE(Modified Duke Critera) Criteria for Diagnosis of Infective Endocarditis Major criteria Positive blood culture Persistently positive blood culture: Blood cultures (2) drawn more than 12 hr ap

23、art. All of three or a majority of four or more separate blood culture, with first and last drawn at least 1 hr apart. Diagnosis of IE(Modified Duke Critera) Criteria for Diagnosis of Infective Endocarditis Major criteria 2. Evidence of endocardial involvement Positive echocardiogram Oscillating int

24、racardiac mass( on valve or supporting structures, or in the path of regurgitant jets, or on implanted material)in the absence of an alternative anatomical explanation. Abscess New partial dehiscence of prosthetic valve, or New valvular regurgitation Diagnosis of IE(Modified Duke Critera) Criteria f

25、or Diagnosis of Infective Endocarditis Minor criteria Predisposition: predisposing heart condition or intravenous drug use Fever 38.0C Vascular phenomena: major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, Janeway lesions Diagnosis

26、of IE(Modified Duke Critera) Criteria for Diagnosis of Infective Endocarditis Minor criteria Immunological phenomena: glomerulonephritis, Osler nodes, rheumatoid factor Microbiological evidence: positive blood culture but not meeting major criterion as noted previously or serologic evidence of activ

27、e infection with organism consistent with infective endocarditis Treatment Two major objectives must be achieved to treat IE effectively. The infecting microorganism in the vegetation must be eradicated. Also, invasive, destructive intracardiac and focal extracardiac complications of infection must

28、be resolved if morbidity and mortality are to be minimized. Antimicrobial Therapy for Specific Organisms Penicillin-susceptible viridans streptococci or streptococcus bovis. -Aqueous penicillin G, Aqueous penicillin plus Gentamicin, or Vancomycin. Relatively penicillin-resistant streptococci. Aqueous penicillin G plus Gentamincin, or Vancomycin （萬古霉素）. Antimicrobial Therapy for Specific Organisms Streptococcus pyogenes, Streptococcus pneumoniae, and group B,