Background: Exercise cardiac stress testing in patients with significant aortic stenosis is generally avoided for safety reasons. Furthermore, the studies that actually addressed the value of exercise testing both with and without myocardial Tc99MIBI scintigraphy for the diagnosis of coronary artery disease (CAD) proved to yield low specificity. Nowadays there are no safe and accurate means for noninvasive assessment of the presence, extent and severity of CAD in patients with significant aortic stenosis. Our study aimed to assess overall safety and usefulness of dipirydamole stress myocardial perfusion scintigraphy for detection of CAD using single-photon emission computed tomography (SPECT) in patients with aortic stenosis. Methods: The study comprised 20 patients with significant aortic stenosis who were compared with 20 patients with CAD designated as CCS II and III. All patients underwent a 5-minute dipirydamole infusion (1.5 mg/kg body weight) protocol stress technetium-99m sestamibi SPECT. Visual 17-segment SPECT analysis used a standard five-point scoring system ranging from 0 (normal tracer uptake) to 4 (absent uptake). The SPECT results were considered abnormal if more than two segments had a stress score 3 2. These results were compared to the same number of patients diagnosed with CAD. All patients also underwent coronary angiography procedure. The respective results in the groups were subsequently compared using the U-Mann-Whitney test and Pearson's correlation nonparametric test. Results: Sensitivity of gated SPECT study was calculated at the level of 83% in the studied group vs. 100% in the controls, with positive predictive value at 88% vs. 90%, respectively. Hemodynamic responses during dipirydamole stress testing demonstrated no significant differences in the net change in systolic blood pressure (30% vs. 25%, patients with aortic stenosis vs. control subjects), heart rate (20% vs. 20%), dyspnea (25% vs. 30%) or incidence of chest pain (30% vs. 30%). Conclusions: Dipirydamole Tc99m MIBI SPECT study was established to be well tolerated, safe and diagnostically accurate in patients with significant aortic stenosis and suspected CAD.
Background: Exercise cardiac stress testing in patients with significant aortic stenosis is generally avoided for safety reasons. Furthermore, the studies that actually addressed the value of exercise testing both with and without myocardial Tc99MIBI scintigraphy for the diagnosis of coronary artery disease (CAD) proved to yield low specificity. Nowadays there are no safe and accurate means for noninvasive assessment of the presence, extent and severity of CAD in patients with significant aortic stenosis. Our study aimed to assess overall safety and usefulness of dipirydamole stress myocardial perfusion scintigraphy for detection of CAD using single-photon emission computed tomography (SPECT) in patients with aortic stenosis. Methods: The study comprised 20 patients with significant aortic stenosis who were compared with 20 patients with CAD designated as CCS II and III. All patients underwent a 5-minute dipirydamole infusion (1.5 mg/kg body weight) protocol stress technetium-99m sestamibi SPECT. Visual 17-segment SPECT analysis used a standard five-point scoring system ranging from 0 (normal tracer uptake) to 4 (absent uptake). The SPECT results were considered abnormal if more than two segments had a stress score 3 2. These results were compared to the same number of patients diagnosed with CAD. All patients also underwent coronary angiography procedure. The respective results in the groups were subsequently compared using the U-Mann-Whitney test and Pearson's correlation nonparametric test. Results: Sensitivity of gated SPECT study was calculated at the level of 83% in the studied group vs. 100% in the controls, with positive predictive value at 88% vs. 90%, respectively. Hemodynamic responses during dipirydamole stress testing demonstrated no significant differences in the net change in systolic blood pressure (30% vs. 25%, patients with aortic stenosis vs. control subjects), heart rate (20% vs. 20%), dyspnea (25% vs. 30%) or incidence of chest pain (30% vs. 30%). Conclusions: Dipirydamole Tc99m MIBI SPECT study was established to be well tolerated, safe and diagnostically accurate in patients with significant aortic stenosis and suspected CAD. 1.34Rest myocardial perfusion imaging and troponin I in the evaluation of chest pain patients. Background: In patients with acute coronary syndromes there is a quantitative relation between cardiac troponins (TnI and T) and the risk of death. Also there is evidence that even a mild elevation of troponins may be related to reversible ischemic injury. Rest myocardial perfusion imaging (RMPI) in the evaluation of patients with chest pain has diagnostic but most important prognostic information. The purpose of this study was to evaluate the relationship between the severity of perfusion defects on RMPI and the maximal level of cTnI, in a group of patients (pts) admitted in the Emergency Department (ED) due to chest pain. Methods: We enrolled hemodynamically stable pts, without prior myocardial infarction, presenting in the ED with ongoing chest pain or an episode of pain ...
Background Myocardial perfusion imaging (MPI) plays a significant role in diagnostic and therapeutic decision making in coronary artery disease (CAD). An isolated apical defect in the 17th segment in SPECT/CT scans is a common finding, sometimes attributed to the apical thinning phenomenon. However, the clinical significance of apical thinning or other isolated apical defects is unknown. Purpose The purpose of this study is to assess the prognostic impact of an isolated apical perfusion defect (17th segment) in patients (P) with suspicion of significant CAD. Methods A cohort of 612 consecutive P that underwent a MPI test with a SPECT/CT scanner, between January 2017 and December 2017, in a single nuclear medicine centre, was included in this retrospective study. The inclusion criteria for this study were either a normal perfusion exam (group 1 – G1) or only an isolated apical defect in the 17th segment, either reversible suggesting ischemia (group 2 – G2) or fixed suggesting necrosis (group 3 – G3). Images with and without attenuation correction were analysed. Mean follow-up was 29±4 months. The chi square test was used for categorical variables, and analysis of variance for continuous variables. Binary logistic regression was used to control for confounding. Results A total of 612 P were included (57% male sex, mean age of 69±10) and divided in G1 (n=494, 80.7%), G2 (n=62, 10%) and G3 (n=56, 9.2%). P in G3 had higher body mass index (31±7, p=0.028) and higher prevalence of dyslipidemia (84%, p=0.001), while P in G1 had lower ejection fraction at rest (54±15, p=0.001). There was no association between the presence of isolated apical defect and all- cause mortality (G1 = 7.3% vs G2 = 6.5% vs G3 = 5.4%, p=0.851). There was a statistically significant difference between groups in the referral for coronary angiography in the bivariate analysis (G1 = 7.9% vs G2 = 35.5% vs G3 = 10.7%, p=0.001), but this association did not remain when accounted for potential confounders (angina, ejection fraction, previous CAD and diabetes) – OR=3.94, 95% CI: [0.968–16.093], p=0.056. In those P that underwent coronary angiography, there was no statistically significant difference between the 3 groups in revascularization of significant CAD (G1 = 38.5% vs G2 = 36.4% vs G3 = 50%, p=0.830). During the follow-up time, 11 P of group 1 suffered an acute coronary syndrome (ACS), but there were no events in group 2 or 3. Conclusion Isolated apical myocardial defect on a SPECT/CT exam has no association with all-cause mortality in this patients. There is no significant difference in referral for coronary angiography or need for coronary revascularization between P with normal exams and P with isolated apical defects. Funding Acknowledgement Type of funding source: None
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.