Myocardial Perfusion SPECT Imaging in Patients after Percutaneous Coronary Intervention

Coronary artery disease (CAD) is the most prevalent form of cardiovascular disease affecting about 13 million Americans, while more than one million percutaneous transluminal intervention (PCI) procedures are performed annually in the USA. The relative high occurrence of restenosis, despite stent implementation, seems to be the primary limitation of PCI. Over the last decades, single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), has proven an invaluable tool for the diagnosis of CAD and patients’ risk stratification, providing useful information regarding the decision about revascularization and is well suited to assess patients after intervention. Information gained from post-intervention MPI is crucial to differentiate patients with angina from those with exo-cardiac chest pain syndromes, to assess peri-intervention myocardial damage, to predict-detect restenosis after PCI, to detect CAD progression in non-revascularized vessels, to evaluate the effects of intervention if required for occupational reasons and to evaluate patients’ long-term prognosis. On the other hand, chest pain and exercise electrocardiography are largely unhelpful in identifying patients at risk after PCI

Tetra­kis(1,3-diphenyl­propane-1,3-dionato)hafnium(IV)

In the title compound, [Hf(C15H11O2)4], the HfIV atom is coordinated by four 1,3-diphenyl­propane-1,3-dionato ligands with an average Hf—O distance of 2.17 (3) Å and O—Hf—O bite angles varying from 74.5 (1) to 75.02 (9)°. The coordination polyhedron shows a slightly distorted Archimedean square-anti­prismatic geometry. The crystal packing is stabilized by weak C—H⋯O inter­actions

Long-term prognostic value of heart-rate recovery after treadmill testing in patients with diabetes mellitus

Background: Heart-rate recovery (HRR) is considered to be an independent predictor of cardiac and all-cause mortality. We examined the long-term prognostic value of HRR in patients suffering from diabetes mellitus. Methods: In this study, we included 258 consecutive patients. Patients whose HRR value or myocardial perfusion imaging could have been influenced by factors other than myocardial ischaemia, were excluded. The value of HRR was defined as the decrease in the heart-rate from peak exercise to 1 min after the termination of the exercise. All patients underwent SPECT myocardial perfusion imaging combined with exercise testing. Cardiovascular death and non-fatal myocardial infarction were considered as hard cardiac events, while late revascularization procedures as soft events. Cox proportional-hazard models were applied to evaluate the association between HRR and the investigated outcome. Results: During the follow-up period (30.8 +/- 6.9 months), hard cardiac events occurred in 21 (8%) patients (15 with abnormal HRR value, p<0.001), while 35 (14%) patients underwent revascularization (31 with abnormal HRR value, p<0.001). Considering it as a continuous variable, HRR was a strong predictor for both hard cardiac (coefficient=-0.41, SE=0.052, p<0.001) and soft cardiac events (coefficient=-0.63, SE=0.058, p<0.001). After adjustments were made for potential confounders, including scintigraphic variables, abnormal HRR remained an independent predictor for hard and soft cardiac events (p<0.001). Conclusion: Our results suggest that among patients with diabetes, a decreased HRR is a significant independent predictor of hard and soft cardiac events. (C) 2008 Elsevier Ireland Ltd. All rights reserved

Long-term prognostic value of Tc-99m tetrofosmin myocardial gated-SPECT imaging in asymptomatic patients after percutaneous coronary intervention

PURPOSE: To evaluate the long-term prognostic value of Tc-99m tetrofosmin myocardial gated-SPECT in asymptomatic patients after coronary artery stenting. MATERIALS AND METHODS: We included 246 consecutive patients in the study. All patients underwent exercise gated-single photon emission computed tomography (SPECT) myocardial imaging 5 to 7 months after percutaneous coronary intervention (PCI) and were followed for a mean period of 8.3 years (SD = 2.9). Myocardial scintigrams were evaluated calculating the summed stress score (SSS), summed rest score, and summed difference score (SDS) indexes. Cardiovascular death and nonfatal myocardial infarction were considered hard cardiac events, whereas late revascularization (>3 months after myocardial SPECT) procedures were considered to be soft events. Cox proportional hazard models were applied to evaluate the association between several variables and the investigated outcome. RESULTS: During the follow-up period, hard cardiac events occurred in 32 (13%) patients (cardiac death occurred in 12 patients and nonfatal myocardial infarction in 20 patients). In addition, 60 (24.4%) patients underwent a late revascularization procedure. When multiple Cox regression analysis was implied, the factors that remained significant in the final model for soft events were SSS, SDS, and angina during exercise testing. In addition, SSS, SDS, and left ventricular dilatation were independently associated with hard cardiac events as defined from the results of multiple analysis. However, SSS and SDS were the only independent predictors for both hard and soft events. CONCLUSIONS: Tc-99m tetrofosmin myocardial perfusion imaging (MPI), performed 6 months post-percutaneous coronary intervention, has an independent and powerful clinical value to predict hard and soft cardiac events in asymptomatic patients after PCI. © 2008 by Lippincott Williams & Wilkins