Nucl Med Mol Imaging.  2008 Oct;42(5):362-368.

The Clinical Efficacy of Lung to Heart Ratio in 1 Hour Delayed Tc-99m Tetrofosmin Gated Myocardial SPECT after Adenosine Stress: Comparison with Coronary Angiography

• Won KS

Abstract

PURPOSE: It is well known that lung to heart ratio (LHR) is one of the high risk findings in Tl-201 myocardial perfusion SPECT. We evaluated the clinical efficacy of LHR to identify severe coronary artery disease in adenosine stress Tc-99m tetrofosmin gated myocardial perfusion SPECT (gSPECT).
MATERIALS AND METHODS
The study population was 157 patients who underwent both adenosine stress Tc-99m gSPECT and coronary angiography (CAG) within one month. According to the results of CAG and gSPECT LHR and the incidence of increased LHR were compared.
RESULTS
Among 53 patients with normal coronary arteries increased LHR was found in 2 patients (3.8%) and 0 in 44 patients (0%) with one vessel disease, 2 in 27 with two vessel disease (7.4%) and 8 in 33 with triple vessel disease (24.2%). Significant differences were found in LHR between subgroups of summed stress score, summed rest score and LV ejection fraction (LVEF). There were weak negative correlation between LHR and LVEF and weak positive correlation between LHR and SSS and SRS.
CONCLUSION
Increased LHR had higher incidence in patients with triple vessel disease, severe LV dysfunction and/or extensive perfusion defect than those of normal group. Although its sensitivity might be low to identify severe coronary artery disease, LHR could be helpful in abnormal myocardial perfusion SPECT to stratify risk and prognosis.

Keyword

Tc-99m tetrofosmin; SPECT; lung to heart ratio; coronary angiography

MeSH Terms

Adenosine
Coronary Angiography
Coronary Artery Disease
Coronary Vessels
Glycosaminoglycans
Heart
Humans
Incidence
Lung
Perfusion
Tomography, Emission-Computed, Single-Photon
Adenosine
Glycosaminoglycans