Diastolic filling parameters derived from myocardial perfusion imaging can predict left ventricular end-diastolic
Dineshkumar Patel1, Vincent J B Robinson, Roque B Arteaga
1Section of Cardiology, Department of Medicine, Medical College of Georgia, Augusta, Georgia 30912, USA.
Insights
New myocardial perfusion imaging (MPI) metrics, including peak filling rate (PFR), can effectively assess diastolic dysfunction in coronary artery disease (CAD) patients. These novel measures surpass traditional lung-to-heart ratio (LHR) in diagnostic accuracy.
Area of Science:
- Cardiology
- Nuclear Medicine
- Medical Imaging
Background:
- Diastolic dysfunction worsens outcomes in coronary artery disease (CAD).
- Elevated left ventricular end-diastolic pressure (LVEDP) is a marker of diastolic dysfunction.
- Traditional stress (201)Tl lung-to-heart ratio (LHR) for LVEDP assessment is unavailable with (99m)Tc agents, limiting diastolic dysfunction evaluation via myocardial perfusion imaging (MPI).
Purpose of the Study:
- To evaluate novel diastolic filling variables derived from MPI using SPECT software for assessing LVEDP in patients with CAD.
- To compare the diagnostic performance of these novel variables against the traditional resting (201)Tl LHR.
Main Methods:
- Fifty-two patients with ejection fraction >or=45% underwent MPI and cardiac catheterization.
- SPECT software was used to obtain peak filling rate (PFR), time to PFR (TPFR), and filling rate during the first third of diastole (1/3FR) from MPI.
- Resting (201)Tl LHR and LVEDP were determined via catheterization.
Main Results:
- PFR, TPFR, and 1/3FR showed significant correlations with LVEDP (r= -0.53, 0.45, -0.45; P<0.001).
- Resting (201)Tl LHR did not correlate significantly with LVEDP (r=0.10, P=0.49).
- Receiver-operating-characteristic analysis demonstrated superior areas under the curve for PFR (0.83), 1/3FR (0.80), and TPFR (0.75) in detecting LVEDP >or=18 mm Hg compared to LHR.
Conclusions:
- Diastolic filling variables (PFR, TPFR, 1/3FR) derived from SPECT MPI correlate well with LVEDP.
- These novel MPI variables are superior to resting (201)Tl LHR for assessing diastolic dysfunction.
- Integrating these variables into MPI can enhance the evaluation of diastolic impairments in CAD patients.
Unlabelled:
Morbidity and mortality increase when diastolic dysfunction accompanies coronary artery disease (CAD). An elevated stress (201)Tl lung-to-heart ratio (LHR) is a traditional marker of elevated left ventricular end-diastolic pressure (LVEDP), which adds prognostic value in CAD. Since the introduction of (99m)Tc-labeled agents, this valuable marker has been lost. Hence, there is only a limited ability to assess diastolic dysfunction by myocardial perfusion imaging (MPI).
Methods:
Fifty-two consecutive patients with an ejection fraction of >or=45% underwent MPI and cardiac catheterization within 15 d. Peak filling rate (PFR), time to PFR (TPFR), and filling rate during the first third of diastole (1/3FR) were obtained from MPI with SPECT software. Resting (201)Tl LHR was calculated manually, and LVEDP was obtained at catheterization.
Results:
PFR, TPFR, and 1/3FR correlated significantly with LVEDP (r= -0.53, 0.45, and -0.45, respectively; P=0.00005, 0.0009, and 0.0009, respectively), whereas resting (201)Tl LHR did not (r=0.10, P=0.49). Receiver-operating-characteristic curve analysis of PFR, TPFR, and 1/3FR for detecting LVEDPs of >or=18 mm Hg showed areas under the curve of 0.83, 0.75, and 0.80, respectively. The combination of PFR and 1/3FR showed a negative predictive value of 84%, a positive predictive value of 86%, and a specificity of 94%.
Conclusion:
Diastolic filling variables obtained with the SPECT software showed a significant correlation with LVEDP. PFR, TPFR, and 1/3FR were superior to resting (201)Tl LHR and showed good sensitivity, specificity, and predictive power for detecting LVEDPs of >or=18 mm Hg. Hence, combining data on the presence of perfusion defects with data on diastolic impairments can be achieved by adding these variables to MPI results.
