This chapter discusses the diagnosis, evaluation and management of infective endocarditis. Patients with infective endocarditis may present acutely with critical illness, or subacutely with low-grade fever, fatigue, weight loss, and distal emboli. Patients may present in acute or progressive congestive heart failure with dyspnea, frothy sputum, and chest pain. The second most common complication is arterial embolization of valve vegetation fragments. Definitive diagnosis is made by positive blood culture(s), and evidence of valvular injury or vegetations on echocardiogram. The most likely cause for sudden deterioration in the patient with suspected infective endocarditis is acute rupture of the aortic or mitral valve. Patients with infective endocarditis presenting with hypotension and evidence of hypoperfusion are usually in septic shock. Norepinephrine is currently the pressor of choice for this condition. In patients with a suspicion of aortic or mitral valve rupture, agents with inotropic effect should be favored.