低血圧・ショックの簡単な心エコー診断

Abstract

Hypotension and shock can be classified as hypotension caused by reduced or maintained left ventricular (LV) ejection. Reduced left ventricular ejection can result from intrinsic left ventricular, aortic valve or mitral valve failure, which includes dilated or ischemic cardiomyopathy, left main trunk disease, acute myocarditis, etc. Acute and subacute severe aortic regurgitation can also cause shock. Echocardiography allows noninvasive diagnosis of infective endocarditis and Takayasu's arteritis to cause severe arotic regurgitation and can also be used to diagnose obstruction of the left ventricular outflow tract. Reduced left ventricular preload can be caused by pericardial effusion and right ventricular ejection failure, and can result from pulmonary embolism, tricuspid regurgitation, right ventricular infarction, tension pneumothorax, hypovolemia and others characterized by a small left ventricle with good ejection fraction. Normal left ventricular ejection may be associated with hypotension. Sepsis, anaphylactic shock and neural disorder are associated with hypotension and normal cardiac output. Pseudohypotension may result from aortic dissection, Takayasu's arteritis, arteriosclerosis obliterans and aortic coarctation. A right parasternal approach enables better visualization of the ascending aorta. Fundamental echochocardiographic scanning allows approximate yet useful diagnosis of hypotension and shock.