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Elizabeth Klodas

Publications and source records attributed to Elizabeth Klodas.

3 recordsLinked to original sources

Quantitation of regional ejection fractions using gated tomographic imaging with 99mTc-sestamibi.

BACKGROUND: Gated single photon emission CT (SPECT) sestamibi imaging allows the simultaneous assessment of myocardial perfusion and left ventricular function. OBJECTIVE: The purpose of this study was to evaluate a technique for quantitative regional wall motion assessment using gated SPECT (99m)Tc-sestamibi imaging. PATIENTS AND INTERVENTIONS: Fourteen subjects without cardiac pathology and 25 patients who had experienced myocardial infarction (MI) were studied. After tomographic reconstruction of gated short-axis slices, the identification of endocardial borders was made using a standard edge-detection program in systole and diastole in each of five selected slices. Regional ejection fraction (EF) and myocardial perfusion were determined for five regions within each slice. Ten patients underwent echocardiographic regional wall-motion analysis, the results of which were compared to corresponding regional EF results. RESULTS: High interobserver reproducibility in the assessment of regional EFs was found, with r values ranging from 0.94 to 0.98. In patients with anterior and inferior MIs, the regional EFs were abnormal in the anterior and septal regions, and the inferior and lateral regions, respectively. The regional EFs correlated significantly with regional perfusion in the anterior walls (r = 0.71; p = 0.0001), the lateral walls (r = 0.66; p = 0.0001), and inferior walls (r = 0.54; p = 0.0004). There was a significant association between the regional EFs and the echocardiographic regional wall motion assessment at the base (p < 0.0001), mid-ventricle (p = 0.0004), and apex (p = 0.0003). CONCLUSIONS: Gated SPECT images obtained (99m)Tc-sestamibi can provide reproducible quantitative, segmental regional EFs for multiple left ventricular slices that are significantly associated with subjective regional wall motion assessment by echocardiography.

Adult↗

Prognostic significance of ischemic electrocardiographic changes during vasodilator stress testing in patients with normal SPECT images.

BACKGROUND: Patients with ischemic electrocardiographic (ECG) findings during exercise stress testing but normal perfusion images generally have a low risk of cardiac death or myocardial infarction (<1% per year). During vasodilator stress testing, however, the prognostic significance of the combination of normal perfusion images and ischemic ECG changes is unknown. METHODS AND RESULTS: Among 5526 patients who underwent vasodilator stress single photon emission computed tomography (SPECT), 49 (0.9%) had normal images but ischemic ECG changes. A unique feature of this population was that 43 (88%) were women with a mean age of 67 +/- 10 years. Ischemic ECG changes occurred at a mean heart rate of 101 +/- 15 beats per minute and persisted for 6.8 +/- 4.7 minutes after termination of drug infusion. During follow-up of 28 +/- 20 months, cardiac death occurred in 2 patients and nonfatal myocardial infarction in 4 patients. The rate of cardiac death or nonfatal myocardial infarction was 4% at 1 year, 10% at 2 years, and 14% at 3 years. Of the 12 patients who underwent coronary angiography or autopsy during follow-up, 11 had multivessel coronary artery disease, indicating that these patients likely had false-negative SPECT image results. Eight patients required coronary revascularization. CONCLUSIONS: The finding of ischemic ECG changes with normal SPECT images during vasodilator infusion is uncommon, occurs primarily in older women, and is associated with a higher subsequent cardiac event rate than is customarily associated with normal images.

Adenosine↗