TABLE 4.
Overview of the identified studies for diagnostic and differential-diagnostic value and their most relevant findings
| Publication | Subjects (n) | Age (years) # | Sex (M:F) | Patient cohort | Most relevant finding |
| Recognising LHD | |||||
| Goda et al. 2019 [50] | 71 | 67±11 | 15:56 | CTEPH | Patients with peak PAWP >20 mmHg (predefined) had larger left atrial volume index (40 versus 34 mL·m−2) than patients with peak PAWP ≤20 mmHg, suggesting LHD |
| Eisman et al. 2018 [32] | 175 | 57±17 | 65:110 | HFpEF+Dyspnoea+Controls | The ULN for PAWP/CO slope was 2 WU in controls; a ULN >2 was characteristic of HFpEF, related to lower exercise capacity, and may also identify HFpEF in patients with normal PAWP at rest |
| Maor et al. 2015¶ [51] | 63 | 60±20 | 18:45 | Dyspnoea | Patients with resting PAWP 12–15 mmHg were 4.5 times more likely to present with a steep PAWP increase during exercise as compared to patients with resting PAWP <12 mmHg |
| Andersen et al. 2015 [52] | 26 | 70±9 | 9:15 | HFpEF+Controls | 94% of patients with left ventricular diastolic dysfunction on echocardiography but 0% of controls had peak PAWP >25 mmHg during exercise A steep PAWP increase may uncover LHD |
| van Empel et al. 2014 [53] | 28 | 62±1 | – | HFpEF+Controls | HFpEF patients had higher PAWP at peak exercise than controls (32 versus 16 mmHg) |
| Borlaug et al. 2010 [54] | 55 | 56±15 | 17:38 | Dyspnoea | Exercise PAWP was used to classify patients with resting PAWP <15 mmHg as having HFpEF (PAWP at exercise ≥25 mmHg) or non-cardiac dyspnoea (PAWP at exercise <25 mmHg) PAWP and sPAP were strongly correlated during exercise |
| Yoshida et al. 1985 [55] | 40 | Range 26–71 | 38:2 | Coronary artery disease+Controls | dPAP/CO slope is steeper in patients with coronary artery disease and angina than in those without angina or in controls |
| Recognising PVD | |||||
| Nagel et al. 2019 [56] | 112 | 58±13 | 24:88 | SSc | SSc patients with resting mPAP 21–24 mmHg had higher peak PVR (2.7 versus 1.8 WU) and lower 6-min walking distance and peak cardiac index than patients with resting mPAP ≤20 mmHg, which may indicate early PVD |
| Gorter et al. 2018 [57] | 161 | 67±11 | 59:102 | HFpEF | Among HFpEF patients (resting PAWP ≥15 mmHg), combined post- and pre-capillary pH was associated with higher peak PVR (4.5 versus 1.9 WU) and lower peak pulmonary arterial compliance (1.4 versus 2.3 mL·mmHg−1) as compared to isolated post-capillary PH, suggesting the presence of PVD |
| Claessen et al. 2015 [20] | 36 | 62±12 | 27:9 | CTEPH+Controls | mPAP/CO slope was steeper in CTEPH patients after pulmonary endarterectomy than in controls and similar to those with unoperated CTEPH, suggesting the presence of residual PVD |
| Taylor et al. 2015 [58] | 39 | 57±9 | 32:7 | HF | At a given CO (∼4.5 L·min−1) during exercise, mPAP was greater in patients with HF and combined pre- and post-capillary PH, than in patients without PH and, to a lesser extent, than in patients with isolated post-capillary PH (∼55 versus ∼32 versus ∼45 mmHg, respectively) |
| Tolle et al. 2008 [59] | 109 | 55±15 | 40:69 | PAH+Controls | Exercise patterns differ between PAH patients and controls PAH presents with a strong initial increase of mPAP followed by a plateau, whereas a continuous moderate mPAP increase was characteristic in controls |
| Recognising LHD and PVD | |||||
| Bentley et al. 2020¶ [60] | 121 | 55 (range 50–60) | 61:60 | Dyspnoea+Controls | Pulse pressure/PAWP slope >2.5 (ULN in controls) uncovers a subgroup among subjects with a normal mPAP/CO slope (ULN in controls 3.2 WU) that is suggestive of an exaggerated pulmonary vascular to PAWP response and might indicate an abnormal PAP response, which is not driven by LHD ULN of the PAWP/CO slope in controls was 2.0 WU |
| Keusch et al. 2014¶ [61] | 101 | 61 (range 52–68) | 31:70 | Dyspnoea | Out of patients with exercise dyspnoea and resting PAP 20–24 mmHg, about the same number had either a steep PAWP or PVR increase, suggesting either post- or pre-capillary cause of mPAP elevation during exercise |
| Hager et al. 2013¶,+ [62] | 173 | 53±13 | 20:153 | SSc+Controls | Exercise may distinguish between pre-capillary (i.e. PVD, characterised by an increase in TPG and PVR during exercise) and post-capillary (i.e. mainly HFpEF, characterised by a steep PAWP/CO slope and no significant change in TPG during exercise) cause of exercise PH in SSc |
| Saggar et al. 2010¶ [63] | 57 | 50±13 | 12:45 | SSc | According to predefined criteria by the authors, SSc patients may reveal pre- or post-capillary causes of exercise PH The main characteristics of post-capillary exercise PH may be the relevant increase of PAWP at peak exercise, while the main characteristics of pre-capillary exercise PH may be an increased PVR and TPG at peak exercise |
M: male; F: female; LHD: left heart disease; CTEPH: chronic thromboembolic pulmonary hypertension; PAWP: pulmonary arterial wedge pressure; HFpEF: heart failure with preserved ejection fraction; CO: cardiac output; WU: Wood unit; ULN: upper limit of normal; sPAP: systolic pulmonary arterial pressure; dPAP: diastolic pulmonary arterial pressure; PVD: pulmonary vascular disease; SSc: systemic sclerosis; mPAP: mean pulmonary arterial pressure; PVR: pulmonary vascular resistance; PH: pulmonary hypertension; PAH: pulmonary arterial hypertension; PAP; pulmonary arterial pressure; TPG: trans-pulmonary gradient. #: data presented as mean±sd or mean (interquartile range), unless otherwise specified; ¶: these studies provide data both for the recognition of LHD and PVD based on parameters of exercise haemodynamic parameters; +: in these studies the exercise protocol was arm lifting with weights, while in all other studies patients performed cycle-ergometry.