The flow-directed, balloon-tipped catheter has facilitated the management of critically ill patients by providing a means of measuring right-sided cardiac pressures and output. In addition, it has been used to measure certain left-sided cardiac pressures. Hellems et al1 reported that a catheter effectively "wedged" in a pulmonary artery (PA) yielded blood that was fully saturated with oxygen and a pressure reflective of that in the left atrium. Subsequently, other investigators substantiated this observation, noting that an oximetrically confirmed PA wedge pressure was similar to left atrial pressure.2,3 In the absence of mitral valve disease, mean PA wedge pressure is similar to mean left ventricular (LV) diastolic pressure, but there is continuing confusion about the relation between mean PA wedge and LV end-diastolic pressures.4 In subjects without cardiac disease, mean left atrial pressure (and likewise mean PA wedge pressure) almost always approximates LV end-diastolic pressure5 and, therefore, can be used to assess LV filling. In contrast, these pressures may be disparate in subjects with cardiac disease.6 This study was performed to examine the relation of mean PA wedge and LV end-diastolic pressures in patients with and without cardiac disease.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine