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Summary Background:The two most useful methods for myocardial viability assessment are perfusion imaging and dobutamine echocardiography. Hypothesis:The present study investigated the additive value of a new method, dobutamine technetium 99m ( 99m Tc)-sestamibi-gated single-photon emission computed tomography (SPECT), which combines these two modalities, to the prediction of wall motion improvement after revascularization. Methods: Fifty-five consecutive patients with ischemic cardiomyopathy, who were referred for viability evaluation, underwent resting and dobutamine (dose, 5‐10 µkg/kg/min) gated SPECT with 99m Tc-sestamibi. Of these patients, 36 underwent coronary artery bypass graft (CABG) within 1 month of the study and 32 had repeat resting gated SPECT within 1 year. Global and regional wall motion, wall thickness, and perfusion were simultaneously analyzed at rest and after dobutamine using the 20-segment model; the sestamibi uptake and wall motion response to dobutamine of each segment were rated quantitatively. Based on these findings, the segments were categorized as normal, viable, or nonviable. The predictive values for wall motion improvement were assessed by perfusion, using cutoffs of 50 and 60% of sestamibi uptake, and thereafter by the addition of dobutamine response in the segments that were rated nonviable. Results: Of the 1,080 myocardial segments studied, 906 (84%) had abnormal wall motion and were analyzed for viability. Concordance between perfusion and wall motion response to dobutamine was 60% with the 50% cutoff of sestamibi uptake, and increased to 65% with the 60% sestamibi cutoff (p < 0.04). The respective predictive values of wall motion improvement using the 50 and 60% cutoff points were as follows: sensitivity 93 and 70%, respectively, (p < 0.01); specificity 59 and 86% (p < 0.001), respectively; accuracy 77% for both. The addition of the wall motion response to dobutamine to the assessment of the nonviable segments by perfusion (60% cutoff) increased the sensitivity from 70 to 85% (p = 0.001) and the negative predictive value from 70 to 81% (p = 0.009); the positive predictive value remained high (86 vs. 82%). No additive value of wall motion response to dobutamine was demonstrated for nonviable segments by perfusion with a 50% cutoff. Conclusion:Dobutamine sestamibi-gated SPECT is a feasible method for the analysis of myocardial perfusion, function, and contractile reserve of individual myocardial segments in patients with ischemic cardiomyopathy. Viability assessment based on a threshold of 60% uptake of sestamibi, with the addition of the wall motion response to dobutamine in the nonviable segments, seems to yield better predictive values for wall motion improvement after CABG.

Hypothesis: The presence of late potentials on the signalaveraged electrocardiogram (SAECG) identifies patients at high risk for development of ventricular tachyarrhythmias after myocardial infarction (MI). Methods: The electrocardiogram and left ventricular function in 65 patients recovering from a first acute anterior wall MI were analyzed. We compared the pattern of the ST segment (isoelectric or elevated) and of the T wave (positive or negative) with the SAECG using an orthogonal bipolar lead configuration (X, Y, Z) with bidirectional Butterworth filtering (Simson's method). Results: Abnormal SAECG was found in 17 (26%) patients; 11 of 18 patients with ST elevation had abnormal SAECG, and only 6 of 47 patients with isoelectric ST segment developed abnormal SAECG (p

Background More and more young people are being referred for evaluation or screening for coronary artery disease (CAD). However, the value of myocardial perfusion imaging (MPI) in this population is unclear, especially in the absence of symptoms. Methods The study sample included 1765 consecutive patients less than 51 years old who were referred to a major medical center for stress/rest MPI study. Clinical and MPI variables were compared between patients with and without known CAD, by gender. Results There were 1346 (76%) men and 419 (24%) women of mean age 44 ± 6 years; 461 (26%) had known CAD. Stress-induced ischemia was detected in 321 patients (18.2%) and significant ischemia in 131 (7.4%); there was no difference in the rate or severity of ischemia by presence of symptoms. Among those without known CAD, the rate of stress-induced ischemia by MPI was significantly lower in women than men. On logistic regression analysis, the independent predictors of ischemia in men were high cholesterol, diabetes, angina during stress testing, ST depression, and smoking (P

Background: Lead III ST-segment depression during acute anterior wall myocardial infarction (AMI) has been attributed to reciprocal changes. However, the value of the T-wave direction (positive or negative) in predicting the site of obstruction and type of the left anterior descending (LAD) artery is not clear and has not been studied before. Hypothesis: The aim of the study was to assess retrospectively the correlation between two patterns of lead III ST-segment depression, and type of LAD artery and its level of obstruction during first AMI. Methods: The study group consisted of 48 consecutive patients, admitted to the coronary care unit for first AMI, who showed ST-segment elevation in lead aVL and ST-segment depression in lead III on admission 12-lead electrocardiogram. The patients were divided by T-wave direction into Group 1 (n = 31), negative T wave, and Group 2 (n = 17), positive T wave. The coronary angiogram was evaluated for type of LAD (“wrapped”, i.e., surrounding the apex or not), site of obstruction (pre- or postdiagonal branch), and other significant coronary artery obstructions. Results: Mean lead III ST-segment depression was 1.99 ± 1.32 mm in Group 1 and 1.13 ± 0.74 mm in Group 2 (p = 0.004); mean ST-segment elevation in aVL was 1.35 ± 0.84 mm and 1.23 ± 0.5 mm, respectively (p = 0.5). A wrapped LAD was found in 12 patients (38.7%) in Group 1 and in 13 in Group 2 (76.4%) (p = 0.02). The sensitivity of lead III ST-segment depression with positive T wave to predict a wrapped LAD was 52%, and the specificity was 82% with a positive predictive value of 76%. On angiography, 25 patients (80%) in Group 1 and 13 (76%) in Group 2 had prediagonal occlusion of the LAD (p = 0.77 ). No significant difference between groups was found for right and circumflex coronary artery involvement or incidence of multivessel disease. Conclusions: The presence of lead III ST-segment depression with positive T wave associated with ST-segment elevation in aVL in the early course of AMI can serve as an early electrocardiographic marker of prediagonal occlusion of a “wrapped” LAD.

Background: The correlation between ST elevation in lead V1 during anterior wall acute myocardial infaction (AMI) and the culprit lesion site in the left anterior descending (LAD) coronary artery is poor. Hypothesis: The study was undertaken to assess the electrocardiographic (ECG) characteristics and angiographic significance of ST-segment elevation in lead V1 during anterior wall acute myocardial infarction (AMI). Methods: Data from 115 patients with anterior wall AMI, who underwent coronary angiography within 14 days of hospitalization, were studied. The admission 12-lead ECG was examined and the coronary angiogram was evaluated for the nature of the conal branch of the right coronary artery (RCA) and for the culprit lesion site in the left anterior descending (LAD) coronary artery. Results: Mean ST-segment deviation and the frequency of patients with ST-segment elevation > 0.1 mV were significantly lower in lead V i than in lead V2 (0.136 $$ 0.111 mV vs. 0.421 $$ 0.260 mV, and 37 vs. 96%, for leads Vi and Vi, respectively). A small conal branch not reaching the interventricular septum (IVS) was more prevalent among patients with ST-segnicni elevation >0.1 mV in lead Vi (67%), whereas a large conal branch was more prevalent in patients with ST-segment deviation (1 mV in that lead (83%, p

Summary: The purpose of the study was to determine whether the initial electrocardiographic pattern is predictive of in-hospital mortality in inferior wall acute myocardial infarction. It is commonly perceived that patients with acute myocardial infarction presenting with greater ST elevation have a worse prognosis. The initial electrocardiogram of patients (n = 213) with inferior wall myocardial infarction was categorized based on the pattern of ST-segment elevation in inferior leads: (A) ST