End-tidal CO2 pressure decreases during exercise in cardiac patients

Abstract

PETCO2 was below normal in cardiac patients at rest and during exercise. PETCO2 was correlated with exercise capacity and cardiac output during exercise, and the sensitivity and specificity of PETCO2 regarding decreased cardiac output were good. PETCO2 may be a new ventilatory abnormality marker that reflects impaired cardiac output response to exercise in cardiac patients diagnosed with heart failure.

Pulmonary function at peak exercise in patients with chronic heart failure

“…In our study population P ETCO2 was reduced in severe CHF at rest and even more reduced at peak exercise. This is partly consistent with other investigations [43] where no decrease from rest to peak was observed.…”

“…Our observations of breathing patterns at rest and at peak of exercise are concordant with previous studies [6,43]. Although patients in Weber class C had an increased ventilatory response during exercise, indicated by an increased V E /V CO 2 slope, their V E was significantly reduced at peak exercise.…”

Relationship of Resting B-type Natriuretic Peptide Level to Cardiac Work and Total Physical Work Capacity in Heart Failure Patients

“…12–14 In studies by Arena et al 14 and Tanabe et al, 15 P ET CO 2 measured at peak exercise was also significantly correlated with ${\dot{\mathrm{normalV}}}_{{\mathrm{normalO}}_{2\text{peak}}}$ ( r = 0.52 and r = 0.68, respectively) and ${\mathrm{V}}_{\mathrm{E}}/{\dot{\mathrm{normalV}}}_{{\mathrm{CO}}_2}$ slope ( r = −0.88 and r = −0.84, respectively). In the present study, we found a similar relationship between peak exercise P ET CO 2 and ${\dot{\mathrm{normalV}}}_{{\mathrm{normalO}}_{2\text{peak}}}$ ( r = 0.62), and P ET CO 2 and ${\mathrm{V}}_{\mathrm{E}}/{\dot{\mathrm{normalV}}}_{{\mathrm{CO}}_2}$ slope ( r = −0.88).…”

“…10,11 In addition, plasma BNP level and both the ${\dot{\mathrm{normalV}}}_{{\mathrm{normalO}}_{2\text{peak}}}$ and the $\mathrm{VE}/{\dot{\mathrm{normalV}}}_{{\mathrm{CO}}_2}$ slope, obtained from CPX, have been shown to have prognostic value for individuals with heart failure. 4,9,10,12 Recently the exercise end-tidal CO 2 pressures (P ET CO 2 ), another variable obtained during CPX, has been shown to be correlated with functional capacity in individuals with heart failure, demonstrating significant relationships to ${\dot{\mathrm{normalV}}}_{{\mathrm{normalO}}_2}$ and $\mathrm{VE}/{\dot{\mathrm{normalV}}}_{{\mathrm{CO}}_2}$ slope. 12–15 …”

“…4,9,10,12 Recently the exercise end-tidal CO 2 pressures (P ET CO 2 ), another variable obtained during CPX, has been shown to be correlated with functional capacity in individuals with heart failure, demonstrating significant relationships to ${\dot{\mathrm{normalV}}}_{{\mathrm{normalO}}_2}$ and $\mathrm{VE}/{\dot{\mathrm{normalV}}}_{{\mathrm{CO}}_2}$ slope. 12–15 …”