Effect of obesity on coronary collateral vessel development in patients with coronary artery disease.

The purpose of this study was to compare coronary collateral circulation and with other risk factors in patients with coronary artery disease and different body mass index. Between January 1999 and December 2001, of 867 patients who underwent angiography for the first time, 90 patients (24 women and 66 men), with occlusion in only 1 coronary artery participated in the study. Information regarding age, body mass index, sex, smoking, hypertension, diabetes mellitus, hyperlipidemia, preinfarction angina, and use of oral beta blockers and nitrates were recorded for all patients. The patients were separated into 2 groups in accordance with development of their coronary collateral circulation; those with insufficient (Rentrop 0, 1, and 2) and those with sufficient coronary collateral circulation. They were also divided into 3 groups on the basis of body mass index as follows: (I) 18.0-24.9 kg/m(2), (II) 25.0-29.9 kg/m(2), and (III) more than 30 kg/m(2). In the obesity and overweight groups, hyperlipidemia, diabetes mellitus, and nitrate use were identified more frequently than in the other groups (p < 0.05). Use of oral nitrates more than 6 months before the myocardial infarction and existence of preinfarction angina affected collateral coronary vessel development in the positive direction (p = 0.01, p = 0.03, respectively). There was no correlation between coronary artery disease and coronary collateral vessel development in the obese patients (p = 0.6). Although it has been shown that coronary collateral vessel development was affected negatively in obese patients with coronary artery disease, no statistical significance was identified.

Differentiating the infarct-related artery on initial electrocardiogram in single or multi-vessel disease in acute inferior myocardial infarction and evaluating involvement of vessels using correspondence analysis.

Initial electrocardiography changes were compared prospectively with the findings of coronary angiography to predict the infarct-related artery (IRA) in cases of single- and multi-vessel disease and to demonstrate the relationship between other coexisting coronary involvements and IRA in patients who presented with acute inferior myocardial infarction (AMI). ST elevations or depressions of at least 1 mm (0.1 mV) were evaluated in the leads I, aVL, and V1-V6. Of the 160 patients hospitalized due to inferior AMI, 153 (96%) underwent coronary angiography using standard methods. The angiograms were screened for stenotic lesions using quantitative coronary angiography to confirm significance, which was considered >50% vessel lumen diameter reduction. Among single-vessel involvements, the IRA was either the circumflex artery (Cx) or right coronary artery (RCA). In conditions in which IRA was detected as either Cx or RCA, 1-, 2-, and 3-vessel involvements were also detected. Correspondence analysis was performed to show the vessel involvements accompanying IRA. Compared with patients with IRA as RCA, the presence of ST depressions in the leads V1 or V2 and aVL were more frequently seen in patients with IRA as Cx (p=0.000, p=0.015, respectively). Among all vessel involvements in which IRA was either Cx or RCA, a ST-segment depression in leads V1 or V2 (p=0.000) and aVL (p=0.000) and a ST-segment elevation in lead I (p=0.005) were considered to be significant for Cx, and a ST-segment depression in lead I for RCA involvement (p=0.010). According to correspondence analysis, the most frequent single-vessel involvement seen in inferior AMI was RCA; when IRA was RCA, a multi-vessel involvement included RCA and Cx; and when IRA was Cx, a single-vessel involvement included the left anterior descending (LAD) artery most frequently, and RCA+LAD less frequently (p=0.000). In inferior AMI, RCA was the most common IRA; however, the possibility of multi-vessel disease is increased when Cx is found to be the IRA. In patients presenting with inferior AMI, the presence of ST-depression in the leads aVL and V1-2 is a sensitive finding that indicates Cx stenosis rather than RCA stenosis and is not affected by coexisting other coronary artery involvements.

Normalization of negative T waves in the chronic stage of Q wave anterior myocardial infarction as a predictor of myocardial viability.

We investigated whether spontaneous normalization of negative T waves (TWN) on infarct-related ECG leads (IRLs) in the chronic phase of Q wave anterior myocardial infarction (MI) could be a predictor of residual viability in infarct areas. We prospectively studied 35 patients (age 60 +/- 8.6 years) in the chronic phase of Q wave anterior MI. Spontaneous TWN (group A, n = 23) were defined as negative T waves that became upright (> or =0.15 mV) in > or =2 IRLs. The presence of negative T waves (group B, n = 12) was defined as symmetric or biphasic negative T wave of > or =0.15 mV. All patients underwent same-day rest 201Tl-stress (99m)Tc sestamibi dual-isotope myocardial perfusion SPECT and 24-hour 201Tl reinjection imaging for ischemia and viability analysis. On scintigraphic examination, ischemic or viable myocardial segments were found in 18 patients (78%) with TWN and 4 patients (33%) of group B (p = 0.013). The use of TWN as a parameter had a marked influence on the sensitivity (82%), specificity (62%), positive (78%) and negative (67%) predictive values and accuracy (74%) of the diagnosis of viable myocardium. If we add the criterion of positive T waves in aVR with negative T waves to our criteria, we found that sensitivity (90%), positive (80%) and negative (80%) predictive values and accuracy (80%) increased. The results of our study suggest that analysis of TWN on IRLs is an accurate marker of residual viability and/or persistent peri-infarct ischemia in patients in the chronic stage of Q wave anterior MI, and therefore optimizes the diagnostic and therapeutic strategies after MI.