Update on the prevention, diagnosis and management of Infective

Endocarditis (IE)

Dr.Ahmed Yahya Mohammed Alarhabi MD, MsC,FcUSM,FACC,MAHA

Consultant Interventional Cardiologist Head of Cardiac Center

HUST

ACC/AHA

IE has the proclivity to cause complications both at the cardiac valve site and at extracardiac locations that can predispose affected patients to serious morbidity and mortality. It is for these reasons that management of IE requires a team approach, which generally includes specialists in infectious diseases, cardiovascular medicine, and cardiovascular surgery with particular expertise in IE. Thus every patient with IE should be managed in the inpatient setting of a medical center with experienced medical and surgical specialists to provide care, which often includes emergent diagnostic and surgical interventions.

Introduction

Infective Endocarditis (IE)

• IE is an infection of the endothelial lining of the heart valves, mitral or tricuspid chorda tendinea, valve annulus, and aortic root.

• Pre-existing heart disease is found in 2/3 of the cases of left-sided IE.

• 1/3 patients have normal or clinically unrecognized valve disease.

• 3.6 to 7.0 cases/100,000 patient-years

Distribution of Types of IE

• Isolated AV IE is observed in 55-60% of cases.

• Isolated MV IE occurs in 25-30% of cases.

• IE of both valves occurs in 15% of cases.

• Prosthetic valve IE constitutes 10-25% of all cases of IE. – Prosthetic valve IE is more common with prosthetic AV, multiple

valves, and after replacement of an infected native valve

The Ultimate Echo GuideRoldan CA.

Distribution of Types of IE

• Right-sided IE constitutes 5-10% of all cases.

– 80% TV is involved

– Most commonly associated with IVDU

– Also occurs in patients with right heart wires or catheters.

• What is the incidence of culture-negative endocarditis?

– 5-10%

The Ultimate Echo GuideRoldan CA.

IE Cont. Def.

• Acute – Toxic presentation

– Progressive valve destruction & metastatic infection developing in days to weeks

– Most commonly caused by S. aureus

• Subacute – Mild toxicity

– Presentation over weeks to months

– Rarely leads to metastatic infection

– Most commonly S. viridans or enterococcus

Infective Endocarditis

• Pathogenesis

Endothelial damage

Platelet-fibrin thrombi

Microorganism adherence

Pathophysiology

• Local destructive effects • Valvular distortion/destruction

• Chordal rupture

• Perforation/fistula formation

• Paravalvular abscess

• Conduction abnormalities

• Purulent pericarditis

• Functional valve obstruction

Pathophysiology

• Embolization • Clinically evident 11 – 43% of patients

• Pathologically present 45 – 65%

• High risk for embolization » Large > 10 mm vegetation

» Hypermobile vegetation

» Mitral vegetations (esp. anterior leaflet)

• Pulmonary (septic) – 65 – 75% of i.v. drug abusers with tricuspid IE

Clinical Features

• Interval between index bacteremia & onset of sx’s usually < 2 weeks

• May be substantially longer in early PVE

• Fever most common sign • May be absent in elderly/debilitated pt.

• Murmur present in 80 – 85% • Generally indication of underlying lesion

• Frequently absent in tricuspid IE

• Changing murmur

Braunwald 10th edition , 2015

Braunwald 10th edition, 2015

Braunwald 8th Edition

PVE commonly extends beyond the valve ring into the annulus which can cause dehiscence, paravalvular regurgitation and

conduction disturbances.

Braunwald 8th Edition

Janeway Lesions

Splinter Hemorrhage

Subconjunctival Hemorrhages

Roth’s Spots

Echo.Cont.

• TTE sensitivity

– Vegetation <5mm 25%

– Between 6-10mm 70%

• TEE sensitivity 90-100%

• Prosthetic endocarditis

– TEE >> TTE

Evangelista Heart 90: 614-617 (2004)

Evangelista Heart 90: 614-617 (2004)

BMJ Vol. 333, Aug. 2006

Evangelista Heart 90: 614-617 (2004)

BMJ Vol. 333, Aug. 2006

BMJ Vol. 333, Aug. 2006

Subaortic Complications of AV Endocarditis

Braunwald 10th edition, 2015

Braunwald 10th edition, 2015

Conclusions

• The epidemiology of IE has changed in developed countries.

• TEE has a 95% sensitivity in detecting vegetations and is also key in finding complications of vegetations.

• Moderate to severe heart failure and vegetation length are important indications for surgery.

• Antibiotic prophylaxis regiman for IE was updated in 2007.

Thank you for attention