There is potential diagnostic utility of SPECT myocardial perfusion imaging (MPI) for ischemic left ventricular (LV) dysfunction in new-onset heart failure (HF), according to a non-randomized observational cohort published in the January/February issue of the Journal of Nuclear Cardiology.
Prem Soman, MD, PhD, from the University of Pittsburgh Medical Center, and colleagues undertook the IMAGING in HF study as a prospective, multi-national trial, designed to explore the role of SPECT MPI as an initial investigative strategy in patients hospitalized with new-onset HF.
The researchers examined 201 patients (approximately 65.3 years old, 43 percent women) hospitalized with their first episode of HF at 14 sites in the United States and the United Kingdom. They performed rest/stress gated SPECT Tc-99m sestamibi (Cardiolite, Lantheus Medical Imaging) MPI during or within two weeks of the index hospitalization, in addition to standard care.
The investigators found that SPECT MPI revealed a broad range of ejection fractions with preserved systolic function in 36 percent of patients. Also, the authors noted that 41 percent of patients had normal perfusion.
In the remaining patients, Soman and colleagues found that perfusion abnormalities were predominantly due to prior heart attack, with extensive ischemia seen only in 6 percent. Among patients who underwent coronary angiography, SPECT performance characteristics revealed excellent negative predictive value (96 percent) for extensive coronary artery disease (CAD). In multivariable analyses, the extent of perfusion abnormality and advancing age predicted the presence of extensive CAD.
“As the first study to examine the utility of SPECT MPI for CAD detection in patients with new-onset heart failure, these results are very encouraging and point to gated SPECT as a potentially useful diagnostic modality for heart failure patients without angina or other clinical indicators of CAD,” Soman said.
The researchers acknowledged that “these patients are unlikely to derive prognostic benefit from coronary revascularization.” However, “patients with HF and extensive CAD may derive a mortality benefit from coronary revascularization and, therefore, identifying etiologically relevant CAD in HF patient is a critical step in their initial evaluation,” the authors wrote.
As a result, Somen and colleagues concluded that while “this pilot study provides encouraging preliminary data regarding the utility of MPI for the diagnosis of ischemic LV dysfunction in patients with new-onset HF, further confirmation of these results is required before clinical implementation can be recommended.”