Author + information
- Ibrahim Danad,
- Pieter G. Raijmakers,
- Hendrik J. Harms,
- Niels van Royen,
- Adriaan A. Lammertsma,
- Mark Lubberink,
- Albert C. van Rossum and
- Paul Knaapen
Nuclear myocardial perfusion imaging (MPI) has become the mainstay for the non-invasive diagnosis of CAD. Clinical decision making is usually based on visual estimates of relative transmural myocardial perfusion. However, nuclear MPI provides no information on transmural myocardial perfusion distribution. Therefore, the present study aimed to determine the quantitative relationship between lesion severity either graded by diameter stenosis or fractional flow reserve (FFR) and transmural myocardial blood flow (MBF) gradient (Endo/Epi) using H2150 positron emission tomography (PET) imaging in patients evaluated for CAD.
Sixty-six patients without a history of CAD were prospectively enrolled and underwent quantitative H2150 PET imaging for quantification of transmural MBF gradients and within one week invasive coronary angiography (ICA) in conjunction with FFR measurements of all coronary arteries irrespective of the PET imaging results.
There was a significant correlation between quantitative angiographic CAD severity on ICA and quantitative estimates of baseline MBF (r=-0.15, p=0.04), hyperemic MBF (r=-0.57, p<0.001), and coronary flow reserve ([CFR], r=-0.49, p<0.001). Hyperemic MBF and CFR were significantly influenced by functional stenosis severity (FFR≤0.80, p<0.001), while baseline MBF was unaffected (p=0.09). Subendocardial and subepicardial MBF at baseline was 1.04 ± 0.26 and 0.87 ± 0.22 mL-min-1-g-1, respectively, yielding an Endo/Epi ratio of 1.20 ± 0.14. During hyperemia, subendocardial and subepicardial MBF was 2.64 ± 1.26 and 2.80 ± 1.22 mL-min-1-g-1, respectively, yielding a significantly lower hyperemic Endo/Epi ratio of 0.94 ± 0.17 (p0.80 [n=145]) and ischemic myocardium (FFR<0.80, [n=53], p<0.01), respectively. Baseline Endo/Epi was unaffected by either angiographic or functional stenosis severity.
Quantitative myocardial perfusion progressively declines during hyperemia with increasing angiographic and functional CAD severity. In addition, cardiac H2150 PET imaging is able to detect transmural MBF gradients and demonstrates a significantly lower hyperemic Endo/Epi ratio in ischemic myocardium.
Poster Sessions, Expo North
Saturday, March 09, 2013, 10:00 a.m.-10:45 a.m.
Session Title: Cardiac PET: Towards Flow Quantification and Novel Applications
Abstract Category: 21. Imaging: Nuclear
Presentation Number: 1139-323
- 2013 American College of Cardiology Foundation