Sundeep Chaudhry

Purpose of review: Cardiopulmonary exercise testing (CPET) is the gold standard for directly assessing cardiorespiratory fitness (CRF) and has a relatively new and evolving role in evaluating atherosclerotic heart disease, particularly in detecting cardiac dysfunction caused by ischemic heart disease. The purpose of this review is to assess the current literature on the link between cardiovascular (CV) risk factors, cardiac dysfunction and CRF assessed by CPET. Recent findings: We summarize the basics of exercise physiology and the key determinants of CRF. Prognostically, several studies have been published relating directly measured CRF by CPET and outcomes allowing for more precise risk assessment. Diagnostically, this review describes in detail what is considered healthy and abnormal cardiac function assessed by CPET. New studies demonstrate that cardiac dysfunction on CPET is a common finding in asymptomatic individuals and is associated with CV risk factors and lower CRF. This review covers how key CPET parameters change as individuals transition from the asymptomatic to the symptomatic stage with progressively decreasing CRF. Finally, a supplement with case studies with long-term longitudinal data demonstrating how CPET can be used in daily clinical decision making is presented. Summary: In summary, CPET is a powerful tool to provide individualized CV risk assessment, monitor the effectiveness of therapeutic interventions, and provide meaningful feedback to help patients guide their path to improve CRF when routinely used in the outpatient setting.

There is growing clinical interest for the use of cardiopulmonary exercise testing (CPET) to evaluate patients with or suspected coronary artery disease (CAD). With mounting evidence, this concise review with relevant teaching cases helps to illustrate how to integrate CPET data into real world patient care. CPET provides a novel and purely physiological basis to identify cardiac dysfunction in symptomatic patients with both obstructive-CAD and nonobstructive-CAD (NO-CAD). In many cases, abnormal cardiac response on CPET may be the only objective evidence of potentially undertreated ischemic heart disease. When symptomatic patients have NO-CAD on coronary angiogram, they are still at increased risk for cardiovascular events. This problem appears to be more common in women than men and may warrant more aggressive risk factor modification. As the main intervention is lifestyle (diet, smoking cessation, exercise) and medical therapy (statins, angiotensin-converting enzyme inhibitors, beta-blockers), serial CPET testing enables close surveillance of cardiovascular function and is responsive to clinical status. CPET can enhance outpatient evaluation and management of CAD. Diagnostically, it can help to identify physiologically significant obstructive-CAD and NO-CAD in patients with normal routine cardiac testing. CPET may be of particular value in symptomatic women with NO-CAD. Prognostically, precise quantification of improvements in exercise capacity may help to improve long-term lifestyle and medication adherence for this chronic condition. This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0