title: Assessing coronary artery disease in patients with anginal chest pain and left bundle branch block:  an emerging role for a new parameter of cardiopulmonary exercise testing.
abstract: Cardiopulmonary exercise testing (CPET) is used in cardiology to grade the severity of heart failure and to assess its prognosis. However, it is unknown whether CPET may be a useful technique to rule out coronary artery disease (CAD) in patients with anginal chest pain and left bundle branch block (LBBB). The aim of this investigation was to evaluate the diagnostic accuracy of CPET to identify CAD in these patients. A cohort of 90 patients with anginal chest pain, 45 with LBBB (group A) and 45 non-LBBB (group B), were studied with CPET and a single-photon emission computed tomographic myocardial perfusion study during the same period. The following variables of CPET were analyzed: peak oxygen uptake (VO2), VO2 at anaerobic threshold, and time to reach the anaerobic threshold (TAT). Group A values were lower compared with group B in peak VO2 (23 ± 6.2 vs. 28 ± 7.6 mLO2 · kg · min; P = 0.002), VO2 at anaerobic threshold (16.1 ± 3.6 vs. 18.9 ± 4.1 mLO2 · kg · min; P =0.001), and TAT (2.7 ± 0.96 vs. 4.4 ± 2.1 min; P < 0.001). Group A showed higher perfusion abnormalities in myocardial perfusion study than group B [27 (60%) vs. 12 (26.7%); P = 0.003]. Multivariate analysis showed that TAT (odds ratio = 1.59; 95% confidence interval, 1.06-2.39; P = 0.02) was the only independent predictor of CAD, after controlling for other factors. Receiver operator characteristic analysis showed an area under the curve of 0.78 for TAT (95% confidence interval, 0.68-0.86; P < 0.0001). In conclusion, our findings suggest that a new functional parameter such as TAT significantly predicts CAD in patients with anginal chest pain and LBBB.
authors.affiliation: Department of Cardiology, Hospital Universitario de Canarias, Ofra s/n La Cuesta Tenerife, Spain. adrvdg@hotmail.com
authors.forename: Alberto
authors.initials: A
authors.lastname: Dominguez-Rodriguez
authors.forename: Pedro
authors.initials: P
authors.lastname: Abreu-Gonzalez
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Gomez
authors.forename: Maria del Carmen
authors.initials: Mdel C
authors.lastname: Garcia-Baute
authors.forename: Eduardo
authors.initials: E
authors.lastname: Arroyo-Ucar
authors.forename: Pablo
authors.initials: P
authors.lastname: Avanzas
authors.forename: Antonio
authors.initials: A
authors.lastname: Lara-Padron
mesh_terms: D015308:Anaerobic Threshold; D000787:Angina Pectoris / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016009:Chi-Square Distribution; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004562:Electrocardiography; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D010101:Oxygen Consumption / Q000502:physiology; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon