Differences in gas exchange of two representative PH patients (one shunt and one no shunt) and a normal subject.

<p>The responses of CPET in three female patients: one normal (aged 40 years; height, 160 cm; weight, 58 kg); one on-shunt-PH patient (aged 35 years; height, 157 cm; weight, 52 kg); and one shunt-patient (aged 38 years; height, 156 cm; weight, 54 kg). Symbols indicate 10-second averaged values. The course of CPET consisted of three minutes of rest, three minutes of unloaded cycling followed by increasing WR of 10 watts/min for PH patients and 20 watts/min for the control, and eventually four minutes of recovery. In the shunt-PH patient, PETO₂, </p><p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E/<p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>O₂ (EqO₂), <p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E/<p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>CO₂ (EqCO₂) and RER concurrently abruptly increased while PETCO₂ and SpO₂ abruptly decreased. The no-shunt-PH patient showed less changes in PETCO₂, PETO₂, RER, <p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E/<p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>O₂ (EqO₂), <p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E/<p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>CO₂ (EqCO₂) and SpO₂.<p></p

CPET of a PH patient who had a late-developing EIS at the end of exercise.

<p>The CPET course was comprised of three minutes of rest, three minutes of unloaded cycling followed by progressively increasing WR of 10 watts/min for the patient and eventually four minutes of recovery. Just before the end of exercise, the PH patient developed a late-developing EIS marked with the gas exchange findings of an abrupt increase in </p><p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E/<p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>O₂ (EqO₂), <p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E/<p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>CO₂ (EqCO₂), PETO₂ and RER, accompanying with a simultaneous decrease in PETCO₂ and SpO₂, then these changes suddenly returned toward their pre-shunt values when exercise stopped.<p></p

Correlation between Selected Resting Hemodynamics and Selected Exercise Parameters for PH Patients.

<p>*:<i>p</i><0.05;</p><p>**:<i>p</i><0.001</p><p>The abbreviation definitions are same as <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121690#pone.0121690.t001" target="_blank">Table 1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121690#pone.0121690.t002" target="_blank">Table 2</a>.</p><p>Correlation between Selected Resting Hemodynamics and Selected Exercise Parameters for PH Patients.</p

Correlation between Selected Resting Hemodynamics and Selected PFT Parameters for PH Patients.

<p>The abbreviation definitions are same as <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121690#pone.0121690.t001" target="_blank">Table 1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121690#pone.0121690.t002" target="_blank">Table 2</a>.</p><p>Correlation between Selected Resting Hemodynamics and Selected PFT Parameters for PH Patients.</p

Changes in CPET Parameters from Rest to End of Unloaded Cycling in PH Patients and Control.

<p>Values are expressed as mean ± SD.</p><p>Δdenotes the changes from rest to the end of unloaded cycling exercise.</p><p>#p < 0.05, vs control group;</p><p>*p < 0.05, vs no-shunt PPH group using unpaired t test.</p><p>The abbreviation definitions are same as <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0121690#pone.0121690.t001" target="_blank">Table 1</a></p><p>Changes in CPET Parameters from Rest to End of Unloaded Cycling in PH Patients and Control.</p

Hemodynamics in Shunt-PH and No Shunt-PH Patients.

<p>Values are expressed as mean ± SD.</p><p>*<i>p</i> < 0.05, shunt group versus no-shunt group using unpaired <i>t</i> test.</p><p>NT-proBNP = n-terminal natriuretic peptide type-B; mPAP = mean pulmonary artery pressure; mRAP = mean right atrial pressure; PVR = pulmonary vascular resistance; CO = cardiac output; CI = cardiac index; PAWP = pulmonary arterial wedge pressure</p><p>Hemodynamics in Shunt-PH and No Shunt-PH Patients.</p

Demographics, 6MWD, Pulmonary Function Testing and Cardiopulmonary Exercise Testing Parameters in PH Patients and Control Subjects.

<p>Values are expressed as mean ± SD and percentage of measured to predicted values (%pred).</p><p>#p < 0.05, control group vs each group of PH patients;</p><p>*p < 0.05, shunt group versus no-shunt group using unpaired t test.</p><p>NYHA = New York Heart Association functional classification; FVC = forced vital capacity; FEV₁ = forced expiratory volume in 1 second; MVV = maximum voluntary ventilation; DL_CO = gas transfer index or diffusing capacity for carbon monoxide; AT = anaerobic threshold; OUES = oxygen uptake efficiency slope; peak </p><p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>O₂ = peak oxygen uptake, <p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>E = minute ventilation; <p></p><p></p><p>V<mo>˙</mo></p><p></p><p></p>CO₂ = carbon dioxide output,<p></p><p>Demographics, 6MWD, Pulmonary Function Testing and Cardiopulmonary Exercise Testing Parameters in PH Patients and Control Subjects.</p