Cardiopulmonary exercise test in patients with refractory angina: functional and ischemic evaluation.

OBJECTIVES: Refractory angina (RA) is a chronic condition clinically characterized by low effort tolerance; therefore, physical stress testing is not usually requested for these patients. Cardiopulmonary exercise testing (CPET) is considered a gold standard examination for functional capacity evaluation, even in submaximal tests, and it has gained great prominence in detecting ischemia. The authors aimed to determine cardiorespiratory capacity by using the oxygen consumption efficiency slope (OUES) in patients with refractory angina. The authors also studied the O2 pulse response by CPET and the association of ischemic changes with contractile modifications by exercise stress echocardiography (ESE). METHODS: Thirty-one patients of both sexes, aged 45 to 75 years, with symptomatic (Canadian Cardiovascular Society class II to IV) angina who underwent CPET on a treadmill and exercise stress echocardiography on a lower limb cycle ergometer were studied. ClinicalTrials.gov: NCT03218891. RESULTS: The patients had low cardiorespiratory capacity (OUES of 1.74 ± 0.4 L/min; 63.9±14.7% of predicted), and 77% of patients had a flattening or drop in O2 pulse response. There was a direct association between Heart Rate (HR) at the onset of myocardial ischemia detected by ESE and HR at the onset of flattening or drop in oxygen pulse response detected by CPET (R = 0.48; p = 0.019). CONCLUSION: Patients with refractory angina demonstrate low cardiorespiratory capacity. CPET shows good sensitivity for detecting abnormal cardiovascular response in these patients with a significant relationship between flattening O2 pulse response during CEPT and contractile alterations detected by exercise stress echocardiography.

Cardiopulmonary exercise test in patients with refractory angina: functional and ischemic evaluation

Abstract Objectives Refractory angina (RA) is a chronic condition clinically characterized by low effort tolerance; therefore, physical stress testing is not usually requested for these patients. Cardiopulmonary exercise testing (CPET) is considered a gold standard examination for functional capacity evaluation, even in submaximal tests, and it has gained great prominence in detecting ischemia. The authors aimed to determine cardiorespiratory capacity by using the oxygen consumption efficiency slope (OUES) in patients with refractory angina. The authors also studied the O2 pulse response by CPET and the association of ischemic changes with contractile modifications by exercise stress echocardiography (ESE). Methods Thirty-one patients of both sexes, aged 45 to 75 years, with symptomatic (Canadian Cardiovascular Society class II to IV) angina who underwent CPET on a treadmill and exercise stress echocardiography on a lower limb cycle ergometer were studied. ClinicalTrials.gov: NCT03218891. Results The patients had low cardiorespiratory capacity (OUES of 1.74 ± 0.4 L/min; 63.9±14.7% of predicted), and 77% of patients had a flattening or drop in O2 pulse response. There was a direct association between Heart Rate (HR) at the onset of myocardial ischemia detected by ESE and HR at the onset of flattening or drop in oxygen pulse response detected by CPET (R = 0.48; p = 0.019). Conclusion Patients with refractory angina demonstrate low cardiorespiratory capacity. CPET shows good sensitivity for detecting abnormal cardiovascular response in these patients with a significant relationship between flattening O2 pulse response during CEPT and contractile alterations detected by exercise stress echocardiography. Highlights OUES analysis is useful for assessing functional capacity in refractory angina. O2 pulse curve is correlated with contractile alterations in exercise echocardiogram. Cardiopulmonary exercise test is useful toll in patients with refractory angina.

Functional capacity and ventilatory efficiency are preserved in well-controlled people living with human immunodeficiency virus/acquired immunodeficiency syndrome.

To verify and compare the responses of the cardiopulmonary variables to the incremental test in physically inactive people living with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) (PLWHA) with well-controlled disease and physically inactive healthy subjects (non-HIV/AIDS). Participants performed a cardiopulmonary exercise test (CPX) on a treadmill. Data were analyzed using the Mann-Whitney test and Spearman correlation. Nine PLWHA (5 women) and 9 non-HIV/AIDS gender and activity level-matched controls were included in the data analysis. Data are expressed in median (range). No difference was shown in the PLWHA group when compared to the control group in functional capacity (peak oxygen consumption [VO2peak]: 29.9 (20.9-36.4) mL/kg/min vs. 32.2 (24.5-39.4) mL/kg/min) and ventilatory efficiency (oxygen uptake efficiency slope [OUES]: 2,058 [1,474-3,204] vs. 2,612 [1,383-4,119]; minute ventilation carbon dioxide production slope: 27.4 [22.5-33.6] vs. 27.5 [20.4-38.1]). The results are also similar to maximal heart rate, oxygen pulse, gas exchange threshold, respiratory compensation point, heart rate recovery, and half-time of VO2peak recovery. OUES had a strong correlation with VO2peak in the PLWHA group (r s =0.70, P=0.04) and control group (r s =0.78, P=0.02). The results of this study indicate that functional capacity and ventilatory efficiency in PLWHA with well-controlled disease are preserved and are not different from sedentary subjects. In this sense, when CPX is unavailable, the aerobic assessment and prescription could be based on simpler procedures used in healthy subjects.

Relationship between non-invasive haemodynamic responses and cardiopulmonary exercise testing in patients with coronary artery disease.

BACKGROUND: Non-invasive assessment of haemodynamic function by impedance cardiography (IC) constitutes an interesting approach to monitor cardiac function in patients with coronary artery disease (CAD). However, such measurements are most often performed at rest, whereas symptoms are also possible during exertion, particularly at higher intensities. In addition, the association between IC during exertion and cardiopulmonary exercise testing (CPX) is not well understood in these patients, which was the aim of this study. METHODS: Nineteen men (age = 62 ± 6 years) with CAD [left ventricular ejection fraction (LVEF) = 61 ± 10%] underwent a CPX using an incremental protocol on a cycle ergometer, with simultaneous measurement of IC. Cardiac output (CO), stroke volume (SV), cardiac index (CI), peak oxygen consumption (VO2 ), the oxygen uptake efficiency slope (OUES), circulatory power and ventilatory power were determined. RESULTS: Pearson product-moment correlation analysis revealed peak VO2 (r = 0·46) was significantly related to CO. Peak oxygen pulse (0·52) was associated with SV. OUES was associated with resting SV (0·47) and with peak SV (r = 0·52). CONCLUSION: These findings suggest that IC indices are associated with certain, but not all, established CPX measures in patients with stable CAD.