Prognostic value of exercise pulmonary haemodynamics in pulmonary arterial hypertension

Abstract

The aim of the study was to investigate the prognostic value of right heart catheterisation variables measured during exercise.55 incident patients with idiopathic, familial or anorexigen-associated pulmonary arterial hypertension (PAH) underwent right heart catheterisation at rest and during exercise and 6-min walk testing before PAH treatment initiation. Patients were treated according to recommendations within the next 2 weeks. Right heart catheterisation was repeated 3-5 months into the PAH treatment in 20 patients.Exercise cardiac index decreased gradually as New York Heart Association (NYHA) functional class increased whereas cardiac index at rest was not significantly different across NYHA groups. Baseline 6-min walk distance correlated significantly with exercise and change in cardiac index from rest to exercise (r50.414 and r50.481, respectively; p,0.01). Change in 6-min walk distance from baseline to 3-5 months under PAH treatment was highly correlated with change in exercise cardiac index (r50.746, p,0.001). The most significant baseline covariates associated with survival were change in systolic pulmonary artery pressure from rest to exercise and exercise cardiac index (hazard ratio 0.56 (95% CI 0.37-0.86) and 0.14 (95% CI 0.05-0.43), respectively).Change in pulmonary haemodynamics during exercise is an important tool for assessing disease severity and may help devise optimal treat-to-target strategies. @ERSpublications Exercise cardiac index correlated with exercise capacity and was associated with long-term survival in PAH

Exertional dyspnoea in pulmonary arterial hypertension

“…The predominant cardiovascular abnormality of PAH on exercise is that of a failure to augment cardiac output on exercise due to increased right ventricular afterload, and this in turn is largely due to a failure to augment cardiac stroke volume [7]. Unlike in healthy subjects, where pulmonary vascular resistance falls on exercise due to pulmonary vascular recruitment and distensibility of the resistive vessels [8], the pulmonary vascular resistance does not fall in PAH to accommodate rises in cardiac output and pulmonary arterial pressure.…”

“…In fact, several studies have been able to demonstrate that this aggregate of pathophysiological abnormalities contains relevant prognostic information. The absence of an adequate right ventricular contractile reserve [9] as well as the failure to increase systemic blood pressure during exercise [10] have been identified as predictors of poor prognosis, whereas greater increases in exercise cardiac output and systolic pulmonary arterial pressure identify better prognosis and response to therapy [7,11].…”

Pulmonary Hemodynamic Response to Exercise in Chronic Thromboembolic Pulmonary Hypertension before and after Pulmonary Endarterectomy

“…The anterior axillary line served as the zero reference in all supine measurements [28] . During constant workload, 3 min after the start of exercise, the measurements of exercise hemodynamic parameters were performed, with a total duration of approximately 5-7 min [19] . Pulmonary pressures were averaged over several respiratory cycles during the constant workload under exercise [29] .…”

“…Along these lines, the echocardiographic parameter 'notch ratio', which describes the pulmonary arterial blood flow pattern, was shown to predict residual PH 3 months after PEA [17] , whereas resting hemodynamic parameters before PEA did not correlate with hemodynamic parameters after PEA [18] . In idiopathic pulmonary arterial hypertension (PAH), recently published data indicate a superiority of exercise pulmonary measurements as prognostic factors [19] . Moreover, in a small cohort of CTEPH patients with persistent dyspnea after PEA but normal pulmonary hemodynamics at rest, the diminished pulmonary arterial compliance (Cpa) during exercise was a strong predictor of limited functional capacity [20] .…”

Right heart catheterisation: best practice and pitfalls in pulmonary hypertension

“…In a prospective, 4-year follow-up study that identified PAH in 89 (12%) out of 722 patients with SSc using RHC, elevated mean RAP was reported to be the strongest haemodynamic predictor of mortality among the SSc-PAH group ( p=0.0001) [53]. In addition, preliminary evidence suggests that exercise haemodynamics during RHC, as previously discussed, may be a more accurate predictor of long-term outcome than haemodynamic variables recorded at rest in patients with PAH [6,54].…”