SPECT Imaging Linked with Cardiac Mortality
The current issue of the Journal of the American College of Cardiology includes an article that describes the value of metabolic single photon emission CT (SPECT) imaging in patients with end-stage renal disease (ESRD). The Japanese research team evaluated the use of SPECT as a tool to predict cardiac mortality in a cohort of patients on chronic hemodialysis.
Almost 400 asymptomatic patients with ESRD were enrolled in the trial. Patients who were enrolled had no previous history of cardiovascular symptoms or apparent cardiac disease. Each of the patients underwent dual-isotope SPECT imaging with two tracers. Uptake on the images procured was graded with a five-point scale for 17 different segments. The team evaluated their findings as Tl and BMIPP scores.
318 patients were followed over time. The rate of mortality attributed to cardiac causes was 15.7 percent over more than three and a half years of follow-up. Causes of death noted include fatal heart attack, death from heart failure, and sudden cardiac death.
Two different groups were created based on findings from the SPECT exams. Patients with BMIPP scores greater than 12 had a lower rate of cardiac death-free survival at 98 percent over three years. Patients with scores under 12 had a cardiac mortality-free survival rate during this time period of 61 percent.
Findings indicate that this type of imaging can identify those patients with myocardium that is metabolically impaired and stratify the extent of impairment in a cohort of patients who do not have other indications of heart disease. The researchers supposed that SPECT can detect severely impaired myocardial fatty acid metabolism. That characteristic is associated with a higher rate of death among patients with ESRD.
January 15, 2008 Related topics: Imaging, Diagnostic, Renal & Urology, Cardiology