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Real-time cine and myocardial perfusion with treadmill exercise stress cardiovascular magnetic resonance in patients referred for stress SPECT.

Raman SV, Dickerson JA, Jekic M, Foster EL, Pennell ML, McCarthy B, Simonetti OP - J Cardiovasc Magn Reson (2010)

Bottom Line: Each modality's images were reviewed blinded to the other's results.Stress cine CMR was completed in 68 +/- 14 sec following termination of exercise, and stress perfusion CMR was completed in 88 +/- 8 sec.Follow-up at 6 months indicated freedom from cardiovascular events in 29/29 CMR-negative and 33/34 SPECT-negative patients.

View Article: PubMed Central - HTML - PubMed

Affiliation: Division of Cardiovascular Medicine, The Ohio State University, Columbus, Ohio, USA. raman.1@osu.edu

ABSTRACT

Background: To date, stress cardiovascular magnetic resonance (CMR) has relied on pharmacologic agents, and therefore lacked the physiologic information available only with exercise stress.

Methods: 43 patients age 25 to 81 years underwent a treadmill stress test incorporating both Tc99m SPECT and CMR. After rest Tc99m SPECT imaging, patients underwent resting cine CMR. Patients then underwent in-room exercise stress using a partially modified treadmill. 12-lead ECG monitoring was performed throughout. At peak stress, Tc99m was injected and patients rapidly returned to their prior position in the magnet for post-exercise cine and perfusion imaging. The patient table was pulled out of the magnet for recovery monitoring. The patient was sent back into the magnet for recovery cine and resting perfusion followed by delayed post-gadolinium imaging. Post-CMR, patients went to the adjacent SPECT lab to complete stress nuclear imaging. Each modality's images were reviewed blinded to the other's results.

Results: Patients completed on average 9.3 +/- 2.4 min of the Bruce protocol. Stress cine CMR was completed in 68 +/- 14 sec following termination of exercise, and stress perfusion CMR was completed in 88 +/- 8 sec. Agreement between SPECT and CMR was moderate (kappa = 0.58). Accuracy in eight patients who underwent coronary angiography was 7/8 for CMR and 5/8 for SPECT (p = 0.625). Follow-up at 6 months indicated freedom from cardiovascular events in 29/29 CMR-negative and 33/34 SPECT-negative patients.

Conclusions: Exercise stress CMR including wall motion and perfusion is feasible in patients with suspected ischemic heart disease. Larger clinical trials are warranted based on the promising results of this pilot study to allow comparative effectiveness studies of this stress imaging system vs. other stress imaging modalities.

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Ischemia by Treadmill Stress CMR and SPECT. Rest and stress CMR and SPECT images in the same patient of Fig. 3 both demonstrate myocardial ischemia, with corresponding obstructive coronary artery disease by angiography. Resting diastolic (A) and systolic (B) cine frames vs. comparable post-exercise cine frames (F, G) show stress-induced inferior wall contractile dysfunction (G, arrowhead). Inferior ischemia is also demonstrated by CMR perfusion imaging (C-rest perfusion vs. H-stress perfusion, arrowhead). Prior MI in the anteroseptum can be seen on late post-gadolinium imaging (E); note some fatty replacement in the infarct region evident as bright intramyocardial signal on noncontrast gradient echo cine frame in panel B. Rest Tc-99 m perfusion SPECT (D) suggests normal perfusion, though somewhat obscured by adjacent bowel uptake; stress Tc-99m perfusion SPECT shows inferior wall defect (I, arrowhead). The patient went on to invasive angiography that showed an occluded right coronary artery (J, arrow) with some left-to-right collateral flow.
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Figure 4: Ischemia by Treadmill Stress CMR and SPECT. Rest and stress CMR and SPECT images in the same patient of Fig. 3 both demonstrate myocardial ischemia, with corresponding obstructive coronary artery disease by angiography. Resting diastolic (A) and systolic (B) cine frames vs. comparable post-exercise cine frames (F, G) show stress-induced inferior wall contractile dysfunction (G, arrowhead). Inferior ischemia is also demonstrated by CMR perfusion imaging (C-rest perfusion vs. H-stress perfusion, arrowhead). Prior MI in the anteroseptum can be seen on late post-gadolinium imaging (E); note some fatty replacement in the infarct region evident as bright intramyocardial signal on noncontrast gradient echo cine frame in panel B. Rest Tc-99 m perfusion SPECT (D) suggests normal perfusion, though somewhat obscured by adjacent bowel uptake; stress Tc-99m perfusion SPECT shows inferior wall defect (I, arrowhead). The patient went on to invasive angiography that showed an occluded right coronary artery (J, arrow) with some left-to-right collateral flow.

Mentions: Test results and 6-month follow-up for all patients are listed in Table 2. Ten patients had ischemia by either stress modality, and 2 patients had fixed defects i.e. infarction without ischemia by both tests; agreement between MRI and SPECT was moderate (κ = 0.58, 95% CI 0.30 - 0.80). Of five patients with ischemia by both tests, all 5 went on to coronary angiography that showed ≥ 70% stenosis requiring revascularization in a coronary artery or bypass graft supplying the region of ischemia (Figures 3 and 4, Additional File 1). Of two patients with fixed defects, both had suffered prior MIs by clinical history and had undergone prior coronary revascularization. Additionally, CMR identified nontransmural infarct scar in 4 patients deemed to have normal stress SPECT exams. In 2 instances where stress SPECT suggested ischemia but stress CMR was negative, one patient went on to invasive coronary angiography and another underwent CT coronary angiography: both had angiographically-normal coronary arteries. Two patients with ischemia by stress CMR not seen by stress SPECT underwent invasive angiography: one was a male with ≥ 70% stenosis requiring revascularization (Figure 5), and the other was a female without epicardial stenosis in whom diffuse subendocardial ischemia was thought to represent microvascular disease. Summary outcomes of CMR, SPECT and angiography are presented in Figure 6.


Real-time cine and myocardial perfusion with treadmill exercise stress cardiovascular magnetic resonance in patients referred for stress SPECT.

Raman SV, Dickerson JA, Jekic M, Foster EL, Pennell ML, McCarthy B, Simonetti OP - J Cardiovasc Magn Reson (2010)

Ischemia by Treadmill Stress CMR and SPECT. Rest and stress CMR and SPECT images in the same patient of Fig. 3 both demonstrate myocardial ischemia, with corresponding obstructive coronary artery disease by angiography. Resting diastolic (A) and systolic (B) cine frames vs. comparable post-exercise cine frames (F, G) show stress-induced inferior wall contractile dysfunction (G, arrowhead). Inferior ischemia is also demonstrated by CMR perfusion imaging (C-rest perfusion vs. H-stress perfusion, arrowhead). Prior MI in the anteroseptum can be seen on late post-gadolinium imaging (E); note some fatty replacement in the infarct region evident as bright intramyocardial signal on noncontrast gradient echo cine frame in panel B. Rest Tc-99 m perfusion SPECT (D) suggests normal perfusion, though somewhat obscured by adjacent bowel uptake; stress Tc-99m perfusion SPECT shows inferior wall defect (I, arrowhead). The patient went on to invasive angiography that showed an occluded right coronary artery (J, arrow) with some left-to-right collateral flow.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2908608&req=5

Figure 4: Ischemia by Treadmill Stress CMR and SPECT. Rest and stress CMR and SPECT images in the same patient of Fig. 3 both demonstrate myocardial ischemia, with corresponding obstructive coronary artery disease by angiography. Resting diastolic (A) and systolic (B) cine frames vs. comparable post-exercise cine frames (F, G) show stress-induced inferior wall contractile dysfunction (G, arrowhead). Inferior ischemia is also demonstrated by CMR perfusion imaging (C-rest perfusion vs. H-stress perfusion, arrowhead). Prior MI in the anteroseptum can be seen on late post-gadolinium imaging (E); note some fatty replacement in the infarct region evident as bright intramyocardial signal on noncontrast gradient echo cine frame in panel B. Rest Tc-99 m perfusion SPECT (D) suggests normal perfusion, though somewhat obscured by adjacent bowel uptake; stress Tc-99m perfusion SPECT shows inferior wall defect (I, arrowhead). The patient went on to invasive angiography that showed an occluded right coronary artery (J, arrow) with some left-to-right collateral flow.
Mentions: Test results and 6-month follow-up for all patients are listed in Table 2. Ten patients had ischemia by either stress modality, and 2 patients had fixed defects i.e. infarction without ischemia by both tests; agreement between MRI and SPECT was moderate (κ = 0.58, 95% CI 0.30 - 0.80). Of five patients with ischemia by both tests, all 5 went on to coronary angiography that showed ≥ 70% stenosis requiring revascularization in a coronary artery or bypass graft supplying the region of ischemia (Figures 3 and 4, Additional File 1). Of two patients with fixed defects, both had suffered prior MIs by clinical history and had undergone prior coronary revascularization. Additionally, CMR identified nontransmural infarct scar in 4 patients deemed to have normal stress SPECT exams. In 2 instances where stress SPECT suggested ischemia but stress CMR was negative, one patient went on to invasive coronary angiography and another underwent CT coronary angiography: both had angiographically-normal coronary arteries. Two patients with ischemia by stress CMR not seen by stress SPECT underwent invasive angiography: one was a male with ≥ 70% stenosis requiring revascularization (Figure 5), and the other was a female without epicardial stenosis in whom diffuse subendocardial ischemia was thought to represent microvascular disease. Summary outcomes of CMR, SPECT and angiography are presented in Figure 6.

Bottom Line: Each modality's images were reviewed blinded to the other's results.Stress cine CMR was completed in 68 +/- 14 sec following termination of exercise, and stress perfusion CMR was completed in 88 +/- 8 sec.Follow-up at 6 months indicated freedom from cardiovascular events in 29/29 CMR-negative and 33/34 SPECT-negative patients.

View Article: PubMed Central - HTML - PubMed

Affiliation: Division of Cardiovascular Medicine, The Ohio State University, Columbus, Ohio, USA. raman.1@osu.edu

ABSTRACT

Background: To date, stress cardiovascular magnetic resonance (CMR) has relied on pharmacologic agents, and therefore lacked the physiologic information available only with exercise stress.

Methods: 43 patients age 25 to 81 years underwent a treadmill stress test incorporating both Tc99m SPECT and CMR. After rest Tc99m SPECT imaging, patients underwent resting cine CMR. Patients then underwent in-room exercise stress using a partially modified treadmill. 12-lead ECG monitoring was performed throughout. At peak stress, Tc99m was injected and patients rapidly returned to their prior position in the magnet for post-exercise cine and perfusion imaging. The patient table was pulled out of the magnet for recovery monitoring. The patient was sent back into the magnet for recovery cine and resting perfusion followed by delayed post-gadolinium imaging. Post-CMR, patients went to the adjacent SPECT lab to complete stress nuclear imaging. Each modality's images were reviewed blinded to the other's results.

Results: Patients completed on average 9.3 +/- 2.4 min of the Bruce protocol. Stress cine CMR was completed in 68 +/- 14 sec following termination of exercise, and stress perfusion CMR was completed in 88 +/- 8 sec. Agreement between SPECT and CMR was moderate (kappa = 0.58). Accuracy in eight patients who underwent coronary angiography was 7/8 for CMR and 5/8 for SPECT (p = 0.625). Follow-up at 6 months indicated freedom from cardiovascular events in 29/29 CMR-negative and 33/34 SPECT-negative patients.

Conclusions: Exercise stress CMR including wall motion and perfusion is feasible in patients with suspected ischemic heart disease. Larger clinical trials are warranted based on the promising results of this pilot study to allow comparative effectiveness studies of this stress imaging system vs. other stress imaging modalities.

Show MeSH
Related in: MedlinePlus