J. G. J. Groothuis

Cardiac PET-CT: advanced hybrid imaging for the detection of coronary artery disease.

Hybrid imaging of positron emission tomography (PET) together with computed tomography (CT) is rapidly emerging. In cardiology, this new advanced hybrid imaging modality allows quantification of cardiac perfusion in combination with assessment of coronary anatomy within a single scanning session of less than 45 minutes. The near-simultaneous anatomical evaluation of coronary arteries using CT and corresponding functional status using PET provides a wealth of complementary information in patients who are being evaluated for (suspected) coronary artery disease, and could help guide clinical patient management in a novel manner. Clinical experience gained with this recently introduced advanced hybrid imaging tool, however, is still limited and its implementation into daily clinical practice remains largely unchartered territory. This review discusses principles of perfusion PET, its diagnostic accuracy, and potential clinical applications of cardiac PET-CT in patients with ischaemic heart disease. (Neth Heart J 2010;18:90–8.)

Combined non-invasive functional and anatomical diagnostic work-up in clinical practice: the magnetic resonance and computed tomography in suspected coronary artery disease (MARCC) study

AIMS The combined use of cardiac computed tomography (CT) coronary angiography (CTCA) and myocardial perfusion imaging allows the non-invasive evaluation of coronary morphology and function. Cardiovascular magnetic resonance (CMR) imaging has several advantages: it can simultaneously assess myocardial perfusion, ventricular and valvular function, cardiomyopathy, and aortic disease and does not involve any additional ionizing radiation. We investigated the combined use of cardiac CT and CMR for the diagnostic evaluation of patients with suspected coronary artery disease (CAD) in clinical practice. METHODS AND RESULTS A total of 192 patients with low or intermediate pre-test probability of CAD underwent CTCA and CMR. All patients with obstructive CAD on CTCA and/or myocardial ischaemia on CMR were referred for invasive coronary angiography (ICA). Fractional flow reserve was measured in case of intermediate lesions (30-70% diameter stenosis) on ICA. Additional cardiac and extra-cardiac findings by CTCA and CMR were registered. The combination of CTCA and CMR significantly improved specificity and overall accuracy (94 and 91%) for the detection of significant CAD compared with their use as a single technique (CTCA 39 and 57%, P < 0.0001; CMR 82 and 83%, P = 0.016). No events were recorded during follow-up (18 ± 6 months) in 104 patients who did not undergo ICA. Furthermore, the combined strategy provided an alternative diagnosis in 19 patients. CONCLUSION The combined use of CTCA and CMR significantly improved specificity and overall diagnostic accuracy for the detection of significant CAD and allowed the detection of alternative (extra-)cardiac disease in patients without significant CAD.

The role of cardiac magnetic resonance imaging in differentiating the underlying causes of left ventricular hypertrophy

The onset of sudden cardiac death and large inter- and intra-familial clinical variability of hypertrophic cardiomyopathy pose an important clinical challenge. Cardiac magnetic resonance imaging is a high-resolution imaging modality that has become increasingly available in the past decade and has the unique possibility to demonstrate the presence of fibrosis or scar using late gadolinium enhancement imaging. As a result, the diagnostic and prognostic potential of cardiac magnetic resonance imaging has been extensively explored in acute and chronic ischaemic cardiomyopathy, as well as in several nonischaemic cardiomyopathies.This review aims to provide a critical overview of recently published studies on hypertrophic cardiomyopathy and discusses the role of cardiac magnetic resonance imaging in differentiating underlying causes of hypertrophic cardiomyopathy, such as familial hypertrophic cardiomyopathy, cardiac involvement in systemic disease and left ventricular hypertrophy due to endurance sports. Also, it demonstrates the use of cardiac magnetic resonance in risk stratification for the onset of sudden cardiac death, and early identification of asymptomatic family members of hypertrophic cardiomyopathy patients who are at risk for the development of hypertrophic cardiomyopathy. (Neth Heart J 2010;18:135-43.)

Improved Correction of Spatial Inhomogeneities of Surface Coils in Quantitative Analysis of First-Pass Myocardial Perfusion Imaging

To test whether image normalization using either a separate 3D proton‐density (PD)‐weighted prescan, or 2D PD‐weighted images prior to the perfusion series, improves correction of differences in spatial sensitivity induced by radiofrequency (RF) surface receiver coils. Originally, this correction was applied using the baseline signal in the myocardium before arrival of the contrast agent. This is of importance, as quantitative analysis of magnetic resonance (MR) myocardial perfusion using deconvolution with the arterial input assumes equal signal sensitivity over the heart.

Towards a noninvasive anatomical and functional diagnostic work-up of patients with suspected coronary artery disease

Combining multidetector computed tomography and cardiovascular magnetic resonance imaging provides the clinician a strategy to comprehensively evaluate coronary morphology and function noninvasively. In the MARCC trial (Magnetic Resonance and CT in suspected CAD) a new noninvasive diagnostic work-up for patients with suspected coronary artery disease will be developed, involving the sequential use of both imaging techniques. (Neth Heart J 2010;18:270-3.)

Low to Intermediate Probability of Coronary Artery Disease: Comparison of Coronary CT Angiography with First-Pass MR Myocardial Perfusion Imaging

PURPOSE To compare coronary computed tomographic (CT) angiography with first-pass magnetic resonance (MR) myocardial perfusion imaging in patients with chest pain and low to intermediate probability of coronary artery disease (CAD). MATERIALS AND METHODS Local ethics committee approval and patient written informed consent were obtained. Patients with chest pain and low to intermediate pretest probability of CAD underwent both coronary CT angiography and MR myocardial perfusion imaging. Coronary CT angiographic and MR myocardial perfusion images were analyzed qualitatively by blinded observers. Obstructive CAD was defined as more than 50% diameter stenosis at coronary CT angiography. Data were expressed with 95% confidence intervals (CIs) calculated from binomial expression. RESULTS In 145 (94.2%) of 154 eligible patients, both coronary CT angiography and MR myocardial perfusion imaging were performed successfully. Mean age was 57 years +/- 10 (standard deviation), and 45.5% of patients were male. Mean interval between coronary CT angiography and MR myocardial perfusion imaging was 4.6 days +/- 3.0; median was 5.0 days. CT coronary angiography revealed obstructive CAD in 52 (35.9%) patients and 78 (17.9%) coronary arteries. At MR myocardial perfusion imaging, myocardial ischemia was demonstrated in 33 (22.8%) patients and 59 (13.6%) vessel territories. Of patients without CAD at coronary CT angiography, 90.5% (57 of 63; 95% CI: 82.6%, 95.0%) had normal myocardial perfusion at MR myocardial perfusion imaging. Of patients with nonobstructive CAD, 83.3% (25 of 30; 95% CI: 69.5%, 91.6%) had normal myocardial perfusion at MR myocardial perfusion imaging. Myocardial ischemia was detected at MR myocardial perfusion imaging in 42.3% (22 of 52; 95% CI: 29.5%, 56%) of patients with obstructive CAD at coronary CT angiography. CONCLUSION MR myocardial perfusion imaging and coronary CT angiography have complementary roles in evaluation of patients who are suspected of having CAD. Coronary CT angiography can be used to reliably rule out CAD, but its capability to demonstrate hemodynamically significant CAD is limited. The combination of both techniques enables the clinician to evaluate morphology and functional relevance of CAD comprehensively and noninvasively.

Positive predictive value of computed tomography coronary angiography in clinical practice.

BACKGROUND Several studies have investigated the diagnostic performance of computed tomography coronary angiography (CTCA) for the detection of significant coronary artery disease (CAD). These studies were performed in patients that were already referred for invasive coronary angiography (ICA) and prevalence of significant CAD was high. Although the negative predictive value of CTCA was consistently high, a wide range of positive predictive values (PPVs) was reported. Thus, the PPV of CTCA in patients that undergo CTCA as part of a clinical diagnostic evaluation remains unclear. This study investigated the PPV of CTCA for the detection of significant CAD in clinical practice. METHODS A total of 181 patients with low to intermediate pre-test probability CAD that were referred for non-invasive evaluation of chest pain underwent 64-slice CTCA. CTCA was scored per segment as normal, non-obstructive CAD or obstructive CAD (>50% diameter stenosis). All patients with obstructive CAD according to CTCA, underwent ICA. Significant CAD was defined as >50% diameter stenosis on ICA. RESULTS According to CTCA, 65 (35.9%) patients had obstructive CAD. In 26 (14.4%) patients, significant CAD was found by ICA. The PPV for detection of significant CAD per patient, per vessel and per segment were 40.0% (26/65, 95% CI: 30.6-50.2%), 31.3% (36/115, 95% CI: 24.7-38.8%) and 25.5% (42/165; 95% CI: 20.3-31.4%), respectively. CONCLUSIONS The PPV of CTCA for detection of significant CAD in patients with low to intermediate probability CAD that are clinically referred for non-invasive evaluation of chest pain is markedly lower than generally reported.

Comparison of dual to single contrast bolus magnetic resonance myocardial perfusion imaging for detection of significant coronary artery disease

To investigate the incremental diagnostic value of dual‐bolus over single‐contrast‐bolus first pass magnetic resonance myocardial perfusion imaging (MR‐MPI) for detection of significant coronary artery disease (CAD).

Comparison of different cardiac risk scores for coronary artery disease in symptomatic women: do female-specific risk factors matter?

Background Cardiovascular diseases remain the leading cause of death in women and there is a need for more accurate risk assessment scores. The aims of our study were to compare the accuracy of several widely used cardiac risk assessment scores in predicting the likelihood of obstructive coronary artery disease (CAD) on CT coronary angiography (CTCA) in symptomatic women and to explore which female-specific risk factors were independent predictors of obstructive CAD on CTCA and whether adding these risk factors to pre-test probability scores would improve their predictive value. Methods and results Data were obtained from a cohort of 228 consecutively included symptomatic women undergoing evaluation for CAD and referred for CTCA. Obstructive CAD was defined as ≥50% luminal stenosis on CTCA. Pre-test probability for CAD was calculated according to the Diamond and Forrester score, New score, Duke clinical score, and an updated Diamond and Forrester score. Female-specific factors were obtained by a written questionnaire. Pre-test probability scores were compared with ROC analysis and showed that only the New score and the updated Diamond and Forrester score were significant predictive scores for obstructive CAD on CTCA (area under the curve, AUC, 0.67, p < 0.01; AUC 0.61, p = 0.04, respectively). Multivariable logistic regression analysis identified that gestational diabetes mellitus (GDM) and oestrogen status were independent predictors of obstructive CAD when adjusted for the pre-test probability scores. The updated Diamond and Forrester score was used for net reclassification improvement (NRI) analysis, since the New score already accounts for oestrogen status. Adding GDM and oestrogen status to the updated Diamond and Forrester score resulted in a significant NRI (p = 0.04). Conclusions There is a large variability in prediction of obstructive CAD using different pre-test probability risk scores in symptomatic women. Logistic regression analysis revealed that oestrogen status and GDM were independently associated with the occurrence of obstructive stenosis on CTCA. The predictive ability of cardiac pre-test probability scores improved significantly with the addition of oestrogen status and GDM.

Coronary anomaly diagnosed by computed tomography coronary angiography in a patient with atypical chest pain

A 64-year-old man was evaluated for atypical chest pain that was present during transurethral prostatectomy. He had no risk factors for coronary artery disease (CAD), no prior history of ischaemic heart disease and had not experienced any symptoms of chest pain during exercise before. Computed tomography coronary angiography (CTCA) was performed to exclude CAD.