Exercise Testing – clinical utility

Sudhir RaoRespiratory registrar

CPET is the gold standard

• For an objective measure of exercise capacity• To identify the mechanisms limiting exercise

tolerance• To establish indices of the patient’s prognosis• Evaluate the effects of therapeutic

interventions

Aim

• To discuss the role of exercise testing in evaluating prognosis in patients with chronic Lung & Heart disease

Common prognostic indicator

• FEV1 – Cystic Fibrosis(CF), COPD• DLCO – ILD, PPH• PaO2, PaCO2- COPD, CF, PPH• BMI- CF, COPD,PPH• Dyspnea- COPD, PF• EF, NYHA - CCF

Survival rate and NYHA classes

FEV1 and prognosis in COPD

AJRCCM 2003; 167:544-549

Exercise variables/indexes that have a high prognostic value in patients with chronic pulmonary & cardiac

diseases

• V’O2 peak- COPD, CF, PPH, CCF• V’O2 at LT(Lactate Threshold)- CCF• V’E/V’CO2 slope at LT- CCF• Arterial O2 desaturation- ILD, CF• Dyspnea- COPD,PF• 6MWT distance- CCF,CF,COPD,PH

V’O2 at rest and during exercise

V’O2- Work rate relationship

~ 10 ml V’O2/min/watt

V’O2 peak and prognosis in CCF

Time (months)

Peak V’O2 (ml/kg/min)

Kaplan-Meier life-table analysis for V’O2 max > 45% vs < 45% predicted

Kleber FX, Circulation 2000

In COPD, V’O2 peak predicts mortality independently of FEV1

Oga T, AJRCCM 2003

Assessment of Survival in Patients with PPH: Importance of CPET

Circulation 2002; 106:319-324