IJCS | Volume 31, Nº3, May/ June 2018

237 or diastolic blood pressure ≥ 90 mmHg, measures taken on the upper limb, at rest and under ideal conditions, and repeated and confirmed, or when antihypertensive agents were used. Diabetes mellitus was identified in the presence of: fasting glycemia ≥ 126 mg/dL; or glycemia ≥ 200 mg/dL after 2 hours of oral glucose overload (75g); or random glycemia ≥ 200 mg/dL associatedwith classic symptoms of hyperglycemia; or use of oral hypoglycemic agents. Exercise stress echocardiography The protocol consisted initially in performing a 12-lead electrocardiogram (ECG) and a resting echocardiography after clinical investigation. Then, ET was performed on a treadmill, and, right after, new echocardiographic images were acquired. All patients were submitted to the standard Bruce or Ellestad protocol during ET. Heart rate was monitored continuously, and the patients were encouraged to achieve their peak physical effort. For metabolic calculations, maximum oxygen consumption at peak exercise (VO 2 max) was obtained indirectly by use of the formula: VO 2 max = 14.76 – 1.379t + 0.451t² - 0.012t³, where t is the duration of ET in minutes. 19 Load was expressed in metabolic equivalents, where 1 MET corresponds to 3.5 mL/kg·min of inhaled VO 2 at rest.20 During ET, the individuals were continuously monitored by use of 3-lead ECG. The electrocardiographic ischemic changes during exercise were horizontal or descending ST-segment depressions ≥ 1 mm for men, and ≥ 1.5 mm for women, at 0.08 second from J point. 21 The ET was performed in an ergonomically designed environment with a continuously trained team, at a reference hospital in cardiology, accredited for specific assessment. The suspension of beta-blockers three days before the ET is recommended routinely, while the other usual drugs are maintained. The ET was performed with a Hewlett Packard/ Phillips SONOS 5500 device until 2012, and, from that year on, with a Phillips IE-33 device, abiding by the technical aspects classically described by Schiller et al. 22 The two-dimensional echocardiographic images were obtained in parasternal and apical acoustic windows, at rest and immediately after exertion, with the patient lying in the left lateral decubitus position and simultaneous electrocardiographic recording. Left ventricular segmental wall motion was assessed by an experienced level III echocardiographer, as recommended by the American Society of Echocardiography. 23 Left ventricular segmental wall thickening was quantitatively assessed at rest and after exertion by use of the model of 16 segments graded as: 1, normal; 2, hypokinetic; 3, akinetic; 4, dyskinetic. The left ventricular wall motion score index (LVWMSI) was calculated at rest and during exertion as the addition of the scores of each of the 16 segments divided by the number of segments assessed at a given time. ALVWMSI of 1 corresponds to normality, between 1.1 and 1.6 represents mild dysfunction, and between 1.61 and 2, moderate dysfunction. Values greater than 2 represent significant dysfunction.22 The difference between the LVWMSI at exertion and at rest is the ΔLVWMSI. The development of a new wall motion change or worsening of the existing dyssynergy (ΔLVWMSI ≠ 0) was considered indicative of myocardial ischemia. Statistical analysis The quantitative variables were described as mean and standard deviation. According to the assumption of sample normality, assessed by use of the Kolmogorov- Smirnov test, the quantitative variables were assessed by use of Student t test for independent groups. For the categorical variables, absolute frequency and percentage were used. To compare the characteristics of categorical variables between the two groups, chi-square test or Fisher exact test, when more appropriate, was used. To assess the association between the variable outcome (myocardial ischemia on ESE) and the associated factors, logistic regression was performed with backward-Wald method. To enter the initial model, all variables with p < 0.25 were admitted, while to remain in the model, p < 0.05 was adopted. The variables were entered into and removed from the model manually, depending on meeting the assumption. The Statistical Package for the Social Sciences (SPSS), version 22.0 (Chicago, IL), was used in the statistical analysis. Ethical aspects This study abided by the ethical principles that regulate human experimentation, and all patients provided written informed consent. This study was approved by the Committee in Ethics and Research of the Sergipe Federal University (CAAE 1818.0.000.107-06). Fontes et al. Alcohol consumption and myocardial ischemia on ESE International Journal of Cardiovascular Sciences. 2018;31(3)235-243 Original Article