Incremental step test in patients with pulmonary hypertension.

ABSTRACT

Cardiopulmonary exercise testing (CPET) on a treadmill or cycle ergometer provides an integrated assessment of the cardiorespiratory system during exertion and is widely used in clinical practice. An incremental step test (IST) can be an alternative for eliciting maximal exercise responses. Therefore, 20 patients with pre-capillary PH (65% female, 41 ±â€¯15 yrs) randomly performed a symptom-limited CPET on a cycle ergometer and IST. Metabolic, cardiovascular, ventilatory and gas exchange variables were recorded during both tests. There was a greater desaturation and higher V̇O2PEAK in IST compared to CPET. The V̇O2GET, HR PEAK (% pred), ΔV̇E/ΔV̇CO2 and ΔHR/ΔV̇O2 were similar in both IST and CPET. By linear regression analyses, the work performed on IST [W = (mass × 9,8 m/s2 x vertical distance)] was a predictor of peak V̇O2 independent of the gender and age (r2 = 077, p = 0001). In conclusion, IST elicited higher peak cardiopulmonary responses and has a good agreement with known severity markers in patients with pre-capillary PH.