Joanna Cwikiel1, Ingebjørg Seljeflot2, Morten W Fagerland3, Kristian Wachtell4, Harald Arnesen5, Eivind Berge6, Arnljot Flaa7. 1. Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital Ullevaal, Norway; Faculty of Medicine, University of Oslo, Norway; Section of Cardiovascular and Renal Research Oslo University Hospital Ullevaal, Norway. Electronic address: jcwikiel@gmail.com. 2. Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital Ullevaal, Norway; Department of Cardiology, Oslo University Hospital Ullevaal, Norway; Faculty of Medicine, University of Oslo, Norway. Electronic address: uxinlj@ous-hf.no. 3. Oslo Centre for Biostatistics and Epidemiology, Research Support Service, Oslo University Hospital, Oslo, Norway. Electronic address: morten.fagerland@medisin.uio.no. 4. Department of Cardiology, Section for Cardiology Intervention, Division of Cardiovascular and Pulmonary Diseases, Oslo University Hospital, Norway. Electronic address: kriwac@ous-hf.no. 5. Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital Ullevaal, Norway; Faculty of Medicine, University of Oslo, Norway. Electronic address: uxhaar@ous-hf.no. 6. Department of Cardiology, Oslo University Hospital Ullevaal, Norway. Electronic address: eivind.berge@medisin.uio.no. 7. Department of Cardiology, Oslo University Hospital Ullevaal, Norway; Section of Cardiovascular and Renal Research Oslo University Hospital Ullevaal, Norway.
Abstract
BACKGROUND: Exercise stress test (EST) has a moderate precision for diagnosis of CAD and could potentially obtain improved accuracy if adding a reliable cardiac biomarker to the test. OBJECTIVE: We aimed to investigate resting levels and change in hs-cTnT during EST in patients with and without angiographically significant CAD. Moreover, we intended to explore the additive value of hs-cTnT to EST results in diagnosis of stable CAD. We hypothesized that hs-cTnT would be higher in CAD patients and increase diagnostic precision of EST. METHOD: Patients presenting with symptoms of stable CAD, performed a maximal EST on a bicycle ergometer. Venous blood samples were taken at rest and within 5 min post-exercise. All patients underwent coronary angiography. Significant CAD was defined as having ≥75% stenosis in one or more segments of the coronary arteries. RESULTS: Out of the 297 participants, significant CAD was found in 111 (37%) patients. Patients with significant CAD compared to without, had higher resting levels of hs-cTnT (median 8.1 vs 5.0 ng/L) and no significant difference in exercise-induced change (median 0.5 vs 0.3 ng/L), p < 0.001 and p = 0.086 respectively. Combined resting hs-cTnT with EST had higher predictive value for significant CAD than EST alone, AUC = 0.751 vs. AUC = 0.637. In an adjusted multivariable regression analysis, resting hs-cTnT >6.0 ng/L was predictive for having significant CAD, OR 2.55 (CI 95% 1.40, 4.65 p = 0.002). CONCLUSION: In patients with suspected stable CAD, hs-cTnT has a predictive value alone, as well as added to a diagnostic EST for CAD.
BACKGROUND: Exercise stress test (EST) has a moderate precision for diagnosis of CAD and could potentially obtain improved accuracy if adding a reliable cardiac biomarker to the test. OBJECTIVE: We aimed to investigate resting levels and change in hs-cTnT during EST in patients with and without angiographically significant CAD. Moreover, we intended to explore the additive value of hs-cTnT to EST results in diagnosis of stable CAD. We hypothesized that hs-cTnT would be higher in CAD patients and increase diagnostic precision of EST. METHOD:Patients presenting with symptoms of stable CAD, performed a maximal EST on a bicycle ergometer. Venous blood samples were taken at rest and within 5 min post-exercise. All patients underwent coronary angiography. Significant CAD was defined as having ≥75% stenosis in one or more segments of the coronary arteries. RESULTS: Out of the 297 participants, significant CAD was found in 111 (37%) patients. Patients with significant CAD compared to without, had higher resting levels of hs-cTnT (median 8.1 vs 5.0 ng/L) and no significant difference in exercise-induced change (median 0.5 vs 0.3 ng/L), p < 0.001 and p = 0.086 respectively. Combined resting hs-cTnT with EST had higher predictive value for significant CAD than EST alone, AUC = 0.751 vs. AUC = 0.637. In an adjusted multivariable regression analysis, resting hs-cTnT >6.0 ng/L was predictive for having significant CAD, OR 2.55 (CI 95% 1.40, 4.65 p = 0.002). CONCLUSION: In patients with suspected stable CAD, hs-cTnT has a predictive value alone, as well as added to a diagnostic EST for CAD.