J. Fred Verzijlbergen

Incremental diagnostic accuracy of hybrid SPECT/CT coronary angiography in a population with an intermediate to high pre-test likelihood of coronary artery disease

AIMS Hybrid myocardial perfusion imaging with single photon emission computed tomography (SPECT) and CT coronary angiography (CCTA) has the potential to play a major role in patients with non-conclusive SPECT or CCTA results. We evaluated the performance of hybrid SPECT/CCTA vs. standalone SPECT and CCTA for the diagnosis of significant coronary artery disease (CAD) in patients with an intermediate to high pre-test likelihood of CAD. METHODS AND RESULTS In total, 98 patients (mean age 62.5 ± 10.1 years, 68.4% male) with stable anginal complaints and a median pre-test likelihood of 87% (range 22-95%) were prospectively included in this study. Hybrid SPECT/CCTA was performed prior to conventional coronary angiography (CA) including fractional flow reserve (FFR) measurements. Hybrid analysis was performed by combined interpretation of SPECT and CCTA images. The sensitivity, specificity, positive (PPV), and negative (NPV) predictive values were calculated for standalone SPECT, CCTA, and hybrid SPECT/CCTA on per patient level, using an FFR <0.80 as a reference for significant CAD. Significant CAD was demonstrated in 56 patients (57.9%). Non-conclusive SPECT or CCTA results were found in 32 (32.7%) patients. SPECT had a sensitivity of 93%, specificity 79%, PPV 85%, and NPV 89%. CCTA had a sensitivity of 98%, specificity 62%, PPV 77%, and NPV 96%. Hybrid analysis of SPECT and CCTA improved the overall performance: sensitivity, specificity, PPV, and NPV for the presence of significant CAD to 96, 95, 96, and 95%, respectively. CONCLUSIONS In > 40% of the patients with a high pre-test likelihood no significant CAD was demonstrated, emphasizing the value of accurate pre-treatment cardiovascular imaging. Hybrid SPECT/CCTA was able to accurately diagnose and exclude significant CAD surpassing standalone myocardial SPECT and CCTA, vs. a reference standard of FFR measurements.

Hybrid myocardial perfusion SPECT/CT coronary angiography and invasive coronary angiography in patients with stable angina pectoris lead to similar treatment decisions

Objectives To evaluate to what extent treatment decisions for patients with stable angina pectoris can be made based on hybrid myocardial perfusion single-photon emission CT (SPECT) and CT coronary angiography (CCTA). It has been shown that hybrid SPECT/CCTA has good performance in the diagnosis of significant coronary artery disease (CAD). The question remains whether these imaging results lead to similar treatment decisions as compared to standalone SPECT and invasive coronary angiography (CA). Methods We prospectively included 107 patients (mean age 62.8±10.0 years, 69% male) with stable anginal complaints and an intermediate to high pre-test likelihood for CAD. Hybrid SPECT/CCTA was performed prior to CA in all patients. The study outcome was the treatment decision categorised as: no revascularisation, percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Treatment decisions were made by two interventional cardiologists and one cardiothoracic surgeon in two steps: first, based on the results of hybrid SPECT/CCTA; second, based on SPECT and CA. Results Revascularisation (PCI or CABG) was indicated in 54 (50%) patients based on SPECT and CA. Percentage agreement of treatment decisions in all patients based on hybrid SPECT/CCTA versus SPECT and CA on the necessity of revascularisation was 92%. Percentage agreement of treatment decisions in patients with matched, unmatched and normal hybrid SPECT/CCTA findings was 95%, 84% and 100%, respectively. Conclusions Panel evaluation shows that patients could be accurately indicated for and deferred from revascularisation based on hybrid SPECT/CCTA.

Added value of hybrid myocardial perfusion SPECT and CT coronary angiography in the diagnosis of coronary artery disease

AIMS Hybrid single photon emission computed tomography (SPECT)/coronary computed tomography angiography (CCTA) has only been evaluated for its diagnostic accuracy as a single test in patients suspected of significant coronary artery disease (CAD). Added value of hybrid SPECT/CCTA beyond usual clinical work-up, or use of each of these tests separately, remains unclear. We evaluated the added value of hybrid myocardial perfusion SPECT (SPECT) and CCTA, beyond pre-test likelihood and exercise stress ECG (X-ECG), in the diagnosis of CAD. METHODS AND RESULTS Two hundred and five patients with stable angina pectoris and intermediate-to-high pre-test likelihood were prospectively included. All patients underwent clinical history and examination, X-ECG, stress and rest SPECT, coronary calcium scoring (CCS) and CCTA. Fractional flow reserve measurement <0.80 or a lesion >50% on coronary angiography (CA) served as reference standard for significant CAD. Multiple imputation was used to correct for missing test results (17-20%). Added value of hybrid SPECT/CCTA to the basic model of pre-test likelihood plus X-ECG was quantified using logistic regression analysis. Model differences were then assessed using differences in C-index and in net reclassification improvement (NRI). The basic model had a C-index of 0.73 (95%CI 0.66-0.80). This significantly increased to 0.85 (95%CI 0.80-0.91) by addition of only SPECT, to 0.90 (95%CI 0.85-0.94) when adding only CCTA, and to 0.96 (95%CI 0.92-0.99) when adding hybrid SPECT/CCTA. The accompanying NRIs were 0.82 (95%CI 0.62-1.02), 0.86 (95%CI 0.66-1.06) and 1.57 (95%CI 1.11-1.59) respectively. CONCLUSION Current analysis resembles clinical routine of layered testing and shows that hybrid SPECT/CCTA imaging has a substantially higher yield than standalone SPECT or CCTA in the diagnostic workup of patients suspected of significant CAD.

Detection of coronary artery disease: Comparison between technetium 99m-labeled sestamibi single-photon emission computed tomography and two-dimensional echocardiography with dipyridamole low-level exercise-stress

BackgroundMyocardial perfusion imaging in conjunction with dipyridamole low-level exercise stress has proved its value in the evaluation of patients with coronary artery disease (CAD). Simultaneous wall motion analysis by two-dimensional (2D) echocardiography may provide additional information beyond that obtained by myocardial perfusion imaging alone. The purpose of this study was to compare 99mTc-labeled sestamibi single-photon emission computed tomography (SPECT) and 2D echocardiography for the evaluation of CAD according to a dipyridamole low-level bicycle exercise stress protocol.Methods and ResultsWe studied 35 consecutive patients referred for the evaluation of chest pain who had undergone coronary arteriography. 99mTc-labeled sestamibi SPECT and 2D echocardiography agreed in 27 patients (80%) studied for overall detection of CAD. On a segmental basis, agreement was found between SPECT and 2D echocardiography in 124 (73%) of 170 segments (Cohen’s kappa=0.43). The accuracy of the combined assessment of myocardial perfusion and echocardiographic wall motion in detecting CAD was 86%, which was not different from the accuracy of SPECT alone (80%; difference not significant) but significantly higher than for 2D echocardiography alone (71%; p=0.03). In the detection of individual coronary artery stenoses, SPECT had a significantly higher accuracy for detecting left anterior descending coronary artery lesions than had 2D echocardiography (80% vs 60%; p<0.01); combining the two methods did not improve the accuracy (80%). The combined assessment slightly improved the accuracy for detecting left circumflex coronary artery stenoses from 71% to 83% (p=0.05).ConclusionThe combined simultaneous assessment of myocardial perfusion by 99mTc-labeled sestamibi SPECT and wall motion by 2D echocardiography did not significantly improve overall accuracy over that obtained by 99mTc-labeled sestamibi SPECT alone. Therefore 99mTc-labeled sestamibi SPECT with dipyridamole low-level exercise stress appears the preferred imaging modality for the evaluation of patients with CAD.

PET scintigraphy of etoposide-induced pulmonary toxicity.

A patient with chronic myelomonocytic leukemia developed drug-induced pulmonary toxicity after using low dose oral etoposide. Because etoposide-induced pulmonary toxicity is an uncommon but serious adverse event, clinicians must be vigilant about the possibility of it, so that the optimal treatment can start as soon as possible. This report demonstrates that PET scintigraphy might be a helpful tool in the early diagnosis of drug-induced pulmonary toxicity.

Non-invasive decision making in stable angina–The response

the comments from Meune et al on our article on treatment decisions based on hybrid single photon emission computed tomography (SPECT) and coronary computed tomography angiography (CCTA) for patients with stable anginal complaints. Prognosis and relief of anginal complaints determine the treatment strategy for each individual patient with coronary artery disease (CAD). In patients with high-risk CAD (two-vessel disease (VD) involving the left anterior descending, three-VD or left main disease), revascularisation is associated with better outcome compared with medical therapy. Moreover, CABG is the standard of care for patients with three-VD or left main disease. Overall, 51% of all included patients suffered significant CAD based on angiography. Of them, 37 (67%) had high-risk CAD. In all, 22% of patients with non-high-risk CAD were on dual antianginal medication. As such, despite similar baseline characteristics, the population differed from patients included in the COURAGE study with regard to severity of CAD. In patients with significant CAD, revascularisation was chosen as treatment strategy for prognostic reasons in two-thirds, as the next best strategy for relief of anginal complaints in 8% and for ‘clinical reasons’ in the remainder. As was shown in the SYNTAX trial, technical aspects of revascularisation (number of lesions, lesion location and angiographic complexity) predict outcome after PCI or CABG. Our study was designed to evaluate whether hybrid SPECT/CCTA would be able to depict the complexity of CAD with enough detail to allow for a reliable treatment decision. We demonstrated an excellent agreement (92%) of panel decisions on the necessity of revascularisation. Despite unmatched SPECT and CCTA results in 41% of patients, the panel correctly appreciated the significance of CAD in these patients. Indeed, a modest agreement was found in the decision on the actual revascularisation strategy. Hybrid SPECT/CCTA was not able to depict angiographic complexity of CAD to allow for a reliable choice between PCI and CABG in patients with an indication for revascularisation. Of course, in heart teams with less experience in evaluating hybrid SPECT/CCTA images these findings will be different.

Imaging of an unusual case of a completely unroofed coronary sinus without persistent left superior vena cava

A 66-year-old male with a history of surgically closed secundum type atrial septal defect (ASD) during childhood and a percutaneous coronary intervention complained of recurrent stable angina. Clinical investigation and 12-lead ECG were unremarkable. He was referred for hybrid myocardial perfusion SPECT (SPECT) and 64-slice CT coronary angiography (CCTA). SPECT showed normal perfusion of the left ventricle (LV) and an enlarged right ventricle (RV). Gated images showed a decreased LV ejection fraction of 50% due to septal wall motion abnormalities …

Comparison of technetium-99m sestamibi left ventricular wall motion and perfusion studies with thallium-201 perfusion imaging: in search of the combination of variables with the highest accuracy in predicting coronary artery disease

Measurements of myocardial perfusion and ventricular function are expected to provide additional information in the detection of coronary artery disease (CAD). The purpose of this study was threefold: (1) to determine to what extent technetium-99m sestamibi wall motion yields different information compared with99mTc-sestamibi and thallium-201 perfusion; (2) to test which information unique to either study is of value in diagnosing CAD; and (3) to assess the combination of variables with the highest diagnostic accuracy. Perfusion and wall motion scores (at rest and during exercise) obtained from visual and quantitative planar201T1 and99mTc-sestamibi scintigraphy of 60 patients with suspected CAD were compared with the angiographic results by means of a polytomous logistic regression model and the diagnostic values were compared with one another. All univariate variables were significantly related to the probability of CAD and its extent. Comparative studies revealed a large degree of correlation between201T1 stress and redistribution variables. The rest99mTc-sestamibi and wall motion studies contained partially different information. Stepwise logistic regression analysis showed the strongest diagnostic power for the combination of201Tl visual analysis of the stress images with quantitative redistribution images (sensitivity 93%, specificity 71%). The diagnostic power was similar for all combinations of visual and quantitative analyses of the exercise and redistribution images. The strongest diagnostic power of the99mTc-sestamibi variables was the score of the diastolic stress image (sensitivity 91%, specificity 79%). Comparable sensitivity and specificity estimates were found when both optimal models were compared. Wall motion studies did not have additional diagnostic power. Although99mTc-sestamibi wall motion studies, both at rest and during exercise, provide information in addition to the99mTc-sestamibi or201Tl myocardial perfusion variables, the information does not enhance the diagnostic power with regard to the prediction of CAD.

Is Attenuation Correction for Myocardial Perfusion Imaging Underutilized

Myocardial SPECT remains an important diagnostic technique in patients suspected of significant coronary artery disease. However, the diagnostic accuracy is hampered by several clinical and technical difficulties. Among these, soft tissue attenuation is one of the most frequent causes. Attenuation correction has the power to correct for these artifacts, increasing the diagnostic accuracy of myocardial SPECT. The current review summarizes the available clinical evidence for attenuation correction and raises the question if this technique is not underutilized in current clinical practice.