Interest of Maximal Oxygen Uptake and Ventilatory Inefficiency (VE/VCO2 Slope) Measured During Cardiopulmonary Exercise Test on Morbidity and Mortality of Lung Resection Candidates

Anatomic lung resection is the treatment of choice for the management of cancerous lung nodules Non-Small-Cell Lung Carcinoma (NSCLC). Systematic functional evaluation can reduce the risk of mortality and morbidity of candidates. Scientific societies recommend a cardiac and spirometry evaluation (including pulmonary diffusion capacity). In this context, patients with FEV1 or less than 80% of the predicted value are subjected to a more thorough evaluation of the physical physical capacity by cardiopulmonary exercise test (CPET) to determine VO2 max (Brunelli et al 2009). Patients with a VO2 max <35% of predicted values or <10ml/kg/min, or a postoperative predicted value of DLCO or FEV1(ppoDLCO, ppoVEMS) less than 30% associated with a postoperative VO2max less than 35% or 10 ml/min/kg should be offered an alternative treatment option (Begum et al 2016). In contrast, a VO2max greater than 20ml/min/kg is considered at low surgical risk (Brunelli et al 2009).

For patients with a VO2 max between 10 and 20ml/kg/min, operability depends on the extent of the resection. In this group of patients, other parameters measured with CPET could be used to optimize the selection of patients given the inability of some the inability of some patients to provide a maximal effort, thus resulting in a sub-maximal evaluation of physical capacity.

The VE/VCO2 slope, ventilatory equivalents or chronotropic recovery are parameters classically used in classically used in heart failure and have recently been shown to be independent prognostic factors as independent prognostic factors for 90-day and 2-year mortality after anatomical lung resection. Moreover, these factors do not depend on the maximality of the test and could again help us to risk-stratify for a sub-maximal and therefore not optimal test.