Recalibrating the Barometer

Abstract

The ability to measure pressures within the heart has been one of the most important diagnostic and therapeutic tools within the cardiologist’s armamentarium over the past half century. Whereas this measurement initially required direct left ventricular puncture,1 transeptal catheterization,2 or retrograde placement of a catheter into the left ventricle, the advent of the Swan-Ganz catheter allowed for accurate estimation of left-sided filling pressures without requiring arterial or intraventricular access. These measurements have been useful to diagnose and treat hemodynamic compromise resulting from cardiac and pulmonary disease and other critical conditions associated with abnormal or unknown volume status. Article p 62 Accurate assessment of left-sided intracardiac filling pressures is particularly crucial for the management of chronic heart failure, in which congestion causes most of the disabling symptoms and hospitalizations.3 High left-sided filling pressures predict rehospitalizations and death, and the degree to which pressures can be reduced predicts survival.4 Skilled estimation of jugular venous pressure, particularly in conjunction with orthopnea, provides the most reliable clinical evidence of elevated left-sided filling pressures.5 However, the accuracy of jugular venous pressure for the detection of elevated right atrial pressure is <75%. The concordance of right-sided and left-sided pressures is about 75% in chronic heart failure without known pulmonary disease,6 and lower when intrinsic lung or pulmonary vascular disease may uncouple ventricular filling pressures. Brain natriuretic peptide levels do not add to the clinical examination in assessing the elevation of filling pressures during admission with chronic heart failure5 and do not change rapidly enough to guide therapy in the inpatient setting7. A reliable noninvasive method to assess elevated filling pressures and their reduction during therapy would refine our current approach to therapy of decompensated heart failure. Noninvasive approaches to measuring intracardiac pressures, particularly diastolic pressures, have been …