Assessment of Myocardial Scar; Comparison between ¹⁸F-FDG PET, CMR and ⁹⁹Tc-Sestamibi

Abstract

Objective: Patients with heart failure and ischaemic heart disease may obtain benefit from revascularisation if viable dysfunctional myocardium is present. Such patients have an increased operative risk, so it is important to ensure that viability is correctly identified. In this study, we have compared the utility of 3 imaging modalities to detect myocardial scar.Design: Prospective, descriptive study. Setting: Tertiary cardiac centre.Patients: 35 patients (29 male, average age 70 years) with coronary artery disease and symptoms of heart failure (NYHA class II). Outcome Measure: The presence or absence of scar using a 20-segment model. Intervention: Assessment of myocardial scar by Results:More segments were identified as nonviable scar using MIBI than with FDG or CMR. FDG identified the least number of scar segments per patient (7.4 +/-4.8 with MIBI vs. 4.9 +/-4.2 with FDG vs. 5.8 +/-5.0 with CMR, p = 0.0001 by ANOVA). The strongest agreement between modalities was in the anterior wall with the weakest agreement in the inferior wall. Overall, the agreement between modalities was moderate to good. Conclusion:There is considerable variation amongst these 3 techniques in identifying scarred myocardium in patients with coronary disease and heart failure. MIBI and CMR identify more scar than FDG. We recommend that MIBI is not used as the sole imaging modality in patients undergoing assessment of myocardial viability.

2014 Korean Guidelines for Appropriate Utilization of Cardiovascular Magnetic Resonance Imaging: A Joint Report of the Korean Society of Cardiology and the Korean Society of Radiology

“…First, when comparing SPECT to CMR, while there was no significant difference in each method's ability to detect myocardial transmural necrosis or normal myocardium, LGE CMR was superior to SPECT in the detection of subendocardial infarction owing to its superior spatial resolution. 97) 98) 99) In addition, a recent prospective study has shown that CMR has a sensitivity of 86.5% and a specificity of 83.4% in the detection of CAD, which are superior to the 66.5% sensitivity and 82.6% specificity reported for SPECT. 13) Likewise, CMR appears to be superior to dobutamine stress echocardiography, which is known to have a similar overall accuracy to that of SPECT on the basis of a meta-analysis that compiled 11 studies and reported a sensitivity of 79% and specificity of 87%.…”

2014 Korean Guidelines for Appropriate Utilization of Cardiovascular Magnetic Resonance Imaging: A Joint Report of the Korean Society of Cardiology and the Korean Society of Radiology

“…Late gadolinium enhancement CMR was also compared to other noninvasive tests for myocardial viability, such as dobutamine stress echocardiography and SPECT. First, when comparing SPECT to CMR, while there was no significant difference in each method's ability to detect myocardial transmural necrosis or normal myocardium, LGE CMR was superior to SPECT in the detection of subendocardial infarction owing to its superior spatial resolution ( 97 , 98 , 99 ). In addition, a recent prospective study has shown that CMR has a sensitivity of 86.5% and a specificity of 83.4% in the detection of CAD, which are superior to the 66.5% sensitivity and 82.6% specificity reported for SPECT ( 13 ).…”

Prometheus’s heart: what lies beneath

“…Despite 201 Tl, 99m Tc‐based radiopharmaceuticals have a worse relationship to flow and minimal redistributing properties, and the mitochondrial uptake of these compounds requires an intact mitochondrial membrane and oxidative metabolism, thus the basis for sensitive viability detection [100]. Recent study compared the detection of viable myocardium by 18 F‐FDG, MRI and 99m Tc‐sestamibi (MIBI) and demonstrated that a significantly higher number of segments were identified as scar by MIBI than by either 18 F‐FDG or CMR [101]. However, the greatest discrepancy between MIBI and 18 F‐FDG and MRI was in detection of scar of the inferior and lateral wall.…”