Performance and Interpretation of Invasive Hemodynamic Exercise Testing

Abstract

Exertional dyspnea is a common complaint for patients seen in pulmonary, cardiac, and general medicine clinics, and elucidating the cause is often challenging, particularly when physical examination, echocardiography, radiography, and pulmonary function test results are inconclusive. Invasive cardiopulmonary exercise testing has emerged as the gold standard test to define causes of dyspnea and exertional limitation in this population. In this review, we describe the methods for performing and interpreting invasive cardiopulmonary exercise testing, with particular attention to the hemodynamic and blood sampling data as they apply to patients being evaluated for heart failure and pulmonary hypertension.

Keywords: catheterizations; dyspnea; exercise testing; hemodynamics; pulmonary function test.

Figure 1

Steps for invasive CPET. BW = balloon wedge; CPET = cardiopulmonary exercise testing; Fr = French; MM = micromanometer; PA = pulmonary artery; PAWP = pulmonary arterial wedge pressure; RAP = right atrial pressure; VO₂ = oxygen consumption.

Figure 2

Findings at Invasive CPET. The top panels display RAP and PAWP at rest, with feet up, and with peak exercise. The asterisk in the top right panel highlights the large V wave in the PAWP with exercise. Dashed line shows mean PAWP measured at mid A wave. The bottom left and bottom middle panels show the RAP and PA tracings at rest and peak exercise. Note differences in tracing quality of fluid-filled catheters and micromanometer wires. The bottom right panel shows lung ultrasound at rest and with exercise, with the development of B lines (arrows) consistent with acute pulmonary edema in this setting. B lines are vertical, laser-like narrow-based lines originating from pleural surface extending to the bottom of the field. Unlike Z lines, B lines move with the lung during respiration. See Figure 1 legend for expansion of abbrevations.