Resistive or dynamic exercise stress testing of the pulmonary circulation and the right heart

There has been recent revival of interest in exercise stress testing of the pulmonary circulation and the right ventricle (RV) for the differential diagnosis of dyspnoea or latent pre- or post-capillary pulmonary hypertension [1–3]. However, guidelines remain cautious because of persistent uncertainties about protocols and the limits of normal [4]. In fact, exercise protocols still vary, with either cycling [3, 6–8], weight lifting [5, 6] or even handgrip [9] modalities, with invasive [3, 5–7, 9] or non-invasive [7, 8, 10] measurements either during [3, 6–10] or after [5] the exercise stress. Furthermore, pulmonary artery pressure (PAP) has been reported either alone [5, 8] or as a function of either cardiac output (CO) [1–3, 7, 10], workload [7, 11] or oxygen uptake ( V′ O2) [12]. In the meantime, flow-corrected PAP during exercise emerges as the measurement of choice for pulmonary vascular function [1–3], and body position may not matter provided a sufficient number of exercise pressure-flow coordinates is generated to smoothen out higher baseline pulmonary vascular resistance (PVR) in the upright position [10], but there remains uncertainty about the most relevant measurements of RV function [7, 13, 14]. Although there is a rationale in favour of incremental dynamic exercise, there is currently no consensus about the optimal exercise modality. We therefore compared the cardiovascular and gas exchange effects of resistive (handgrip), mixed resistive/dynamic (weight lifting) or dynamic (cycling) exercise on the pulmonary circulation and the RV in healthy volunteers. Exercise stress testing of the pulmonary circulation and the right heart should be dynamic, not resistive <http://ow.ly/ZEyF30c9RlP>