Thallium-201 gated single-photon emission tomography for assessing left ventricular volumes and function in patients with aortic valve stenosis: Comparison with echocardiography as the reference standard.

Background: Aortic valve stenosis (AS) is characterized by chronic left ventricular pressure overload, leading to left ventricular hypertrophy (LVH). We assessed correlations in left ventricular volumes and function between echocardiography and quantitative gated SPECT (QGS) in patients with AS.

Methods And Results: The study population consisted of 28 patients with AS defined as a peak velocity of > 3.0 m/s and 28 age- and sex-matched control subjects. Patients with AS had a peak pressure gradient of 73.4 ± 24.5 mm Hg and a larger LVM index compared to control subjects (115.5 ± 29.2 g/m vs 78.3 ± 12.1 g/m, p < 0.01). There were good correlations in end-diastolic volume and end-systolic volume between echocardiography and QGS in patients with AS as well as control subjects. Bland-Altman plot for end-systolic volume showed a significant negative slope of - 0.51 in patients with AS. There was a good correlation in ejection fraction between the 2 methods in patients with AS as well as control subjects. However, Bland-Altman plots showed significant negative slopes of - 0.40 in patients with AS and - 0.74 in control subjects.

Conclusions: Our data suggested that QGS was a useful method for assessing left ventricular volumes and function even in patients with AS. Cardiologists should recognize its specific characteristics.