Csilla Celeng

Plaque assessment by coronary CT

Coronary CT angiography (CTA) has emerged as a highly reliable and non-invasive modality for the exclusion of coronary artery disease. Recent technological advancements in coronary CTA imaging allow for robust qualitative and quantitative assessment of atherosclerotic plaques. Furthermore, CTA is a promising modality for functional evaluation of coronary lesions. Individual plaque features, the extent and severity of atherosclerotic plaque burden were proposed to improve cardiovascular risk stratification. It has been suggested that total atherosclerotic plaque burden is a stronger predictor of coronary events than total ischemia burden. The quest to noninvasively detect individual vulnerable plaques still remains. In the current review we sought to summarize state-of-the-art coronary artery plaque assessment by CTA.

Non-invasive and invasive imaging of vulnerable coronary plaque

Vulnerable plaque is characterized by a large necrotic core and an overlying thin fibrous cap. Non-invasive imaging modalities such as computed tomography angiography (CTA) and magnetic resonance imaging (MRI) allow for the assessment of morphological plaque characteristics, while positron emission tomography (PET) enables the detection of metabolic activity within the atherosclerotic lesions. Invasive imaging modalities such as intravascular ultrasound (IVUS), optical-coherence tomography (OCT), and intravascular MRI (IV-MRI) display plaques at a high spatial resolution. Near-infrared spectroscopy (NIRS) allows for the detection of chemical components of atherosclerotic plaques. In this review, we describe state-of-the-art non-invasive and invasive imaging modalities and stress the combination of their advantages to identify vulnerable plaque features.

Potential for coronary CT angiography to tailor medical therapy beyond preventive guideline-based recommendations: Insights from the ROMICAT I trial

BACKGROUND Coronary CT angiography (CCTA) is used in the emergency department to rule out acute coronary syndrome in low-intermediate risk patients. OBJECTIVES We evaluated the potential of CCTA to tailor aspirin (ASA) and statin therapy in acute chest pain patients. METHODS We included all patients in the ROMICAT I trial who underwent CCTA before admission. Results of CCTA were blinded to caretakers. We documented ASA and statin therapy at admission and discharge and determined change in medications during hospitalization, agreement of discharge medications with contemporaneous guidelines, and agreement with the presence and severity of coronary artery disease (CAD) as determined by CCTA. RESULTS We included 368 patients (53 ± 12 years; 61% male). Baseline medical therapy at presentation included 27% on ASA and 24% on statin. Most patients who qualified for secondary prevention were on ASA and statin therapy at discharge (95% and 80%, respectively), whereas among those qualifying for primary prevention therapy, only 59% of patients were on aspirin and 33% were on statin at discharge. Excluding secondary prevention patients, among those with CCTA-detected CAD, only 66/131 (50%) were on ASA at discharge and only 53/131 (40%) were on statin. Conversely, in those without CCTA-detected CAD, 54/156 (35%) were on ASA and 20/151 (13%) were on statin at discharge. CONCLUSION There are significant discrepancies between discharge prescription of statin and ASA with the presence and extent of CAD. CCTA presents an efficient opportunity to tailor medical therapy to CAD in patients undergoing CCTA as part of their acute chest pain evaluation.

Prognostic Value of Coronary Computed Tomography Angiography in Patients With Diabetes: A Meta-analysis

OBJECTIVE The usefulness of coronary computed tomography angiography (CTA) for the evaluation of coronary artery disease (CAD) in patients with diabetes is ambiguous. We therefore performed a meta-analysis of studies reporting event rates and hazard ratios (HR) to determine the prognostic value of CTA in this patient population. RESEARCH DESIGN AND METHODS We searched PubMed and Embase up to November 2015. Study subjects’ characteristics, events (all-cause mortality or cardiac death, nonfatal myocardial infarction, unstable angina pectoris, stroke, revascularization), and events excluding revascularization were collected. We calculated the prevalence of obstructive and nonobstructive CAD on CTA, annualized event rates, and pooled unadjusted and adjusted HR using a generic inverse random model. RESULTS Eight studies were eligible for inclusion into this meta-analysis, with 6,225 participants (56% male; weighted age, 61 years) with a follow-up period ranging from 20 to 66 months. The prevalence of obstructive CAD, nonobstructive CAD, and no CAD was 38%, 36%, and 25%, respectively. The annualized event rate was 17.1% for obstructive CAD, 4.5% for nonobstructive CAD, and 0.1% for no CAD. Obstructive and nonobstructive CAD were associated with an increased HR of 5.4 and 4.2, respectively. A higher HR for obstructive CAD was observed in studies including revascularization compared with those that did not (7.3 vs. 3.7, P = 0.124). CONCLUSIONS CTA in patients with diabetes allows for safely ruling out future events, and the detection of CAD could allow for the identification of high-risk patients in whom aggressive risk factor modification, medical surveillance, or elective revascularization could potentially improve survival.

Multimodality Imaging of Giant Right Coronary Aneurysm and Postsurgical Coronary Artery Inflammation

A 52-year-old former recreational marathon runner with a history of permanent atrial fibrillation was referred to our institution because of fatigue and shortness of breath. His 12-lead ECG indicated atrial fibrillation with incomplete right bundle-branch block and inferolateral T-wave inversions (Figure 1). The chest x-ray showed an abnormal structure with a circular silhouette at the projection of the right atrium in the anterior-posterior view (Figure 2). Transthoracic echocardiography revealed a vascular tubular structure adjacent to the atrioventricular groove (Figure 3A and 3B and Movies I and II in the online-only Data Supplement). Subsequently, we performed a coronary computed tomography angiography (CCTA) using a 256-slice multidetector-row CT (Philips Brilliance iCT, Best, The Netherlands) with a tube voltage of 100 kV and a tube current of 300 mA. Because of the atrial fibrillation (mean heart rate, 57 bpm; range, 45–110 bpm), an arrhythmia detection algorithm was used during the prospective ECG-triggered image acquisition. The CCTA depicted a normal left coronary system with no signs of atherosclerosis. The ostium of the right coronary artery (RCA) was dilated (10×8 mm), and the proximal segment of the vessel formed a giant aneurysm (Figure 4A and 4B). The location of the aneurysm was noted to be anterior to the right atrium, adjacent to the atrioventricular groove, and its size measured 62×60×86 mm (Figure 4D–4F). Distal to the aneurysm, the extremely tortuous RCA remained enlarged (12–14 mm) and showed a fistulous communication with the coronary sinus (Figure 4C). The length of the whole RCA was ≈80 cm along its centerline. Subsequent invasive coronary angiography confirmed the CCTA findings (Movies III and IV in the online-only Data Supplement). Surgery was performed to repair the RCA and to stop …

Iterative model reconstruction reduces calcified plaque volume in coronary CT angiography

OBJECTIVE To assess the impact of iterative model reconstruction (IMR) on calcified plaque quantification as compared to filtered back projection reconstruction (FBP) and hybrid iterative reconstruction (HIR) in coronary computed tomography angiography (CTA). METHODS Raw image data of 52 patients who underwent 256-slice CTA were reconstructed with IMR, HIR and FBP. We evaluated qualitative, quantitative image quality parameters and quantified calcified and partially calcified plaque volumes using automated software. RESULTS Overall qualitative image quality significantly improved with HIR as compared to FBP, and further improved with IMR (p<0.01 all). Contrast-to-noise ratios were improved with IMR, compared to HIR and FBP (51.0 [43.5-59.9], 20.3 [16.2-25.9] and 14.0 [11.2-17.7], respectively, all p<0.01) Overall plaque volumes were lowest with IMR and highest with FBP (121.7 [79.3-168.4], 138.7 [90.6-191.7], 147.0 [100.7-183.6]). Similarly, calcified volumes (>130 HU) were decreased with IMR as compared to HIR and FBP (105.9 [62.1-144.6], 110.2 [63.8-166.6], 115.9 [81.7-164.2], respectively, p<0.05 all). High-attenuation non-calcified volumes (90-129 HU) yielded similar values with FBP and HIR (p=0.81), however it was lower with IMR (p < 0.05 both). Intermediate- (30-89 HU) and low-attenuation (<30 HU) non-calcified volumes showed no significant difference (p=0.22 and p=0.67, respectively). CONCLUSIONS IMR improves image quality of coronary CTA and decreases calcified plaque volumes.

Use of Coronary Computed Tomographic Angiography Findings to Modify Statin and Aspirin Prescription in Patients With Acute Chest Pain

Coronary CT angiography (CCTA) is used in patients with low-intermediate chest pain presenting to the emergency department for its reliability in excluding acute coronary syndrome (ACS). However, its influence on medication modification in this setting is unclear. We sought to determine whether knowledge of CCTA-based coronary artery disease (CAD) was associated with change in statin and aspirin prescription. We used the CCTA arm of the Rule Out Myocardial Infarction using Computed Angiographic Tomography II multicenter, randomized control trial (R-II) and comparison cohort from the observational Rule Out Myocardial Infarction using Computed Angiographic Tomography I cohort (R-I). In R-II, subjects were randomly assigned to CCTA to guide decision making, whereas in R-I patients underwent CCTA with results blinded to caregivers and managed according to standard care. Our final cohort consisted of 277 subjects from R-I and 370 from R-II. ACS rate was similar (6.9% vs 6.2% respectively, p = 0.75). For subjects with CCTA-detected obstructive CAD without ACS, initiation of statin was significantly greater after disclosure of CCTA results (0% in R-I vs 20% in R-II, p = 0.009). Conversely, for subjects without CCTA-detected CAD, aspirin prescription was lower with disclosure of CCTA results (16% in R-I vs 4.8% in R-II, p = 0.001). However, only 68% of subjects in R-II with obstructive CAD were discharged on statin and 65% on aspirin. In conclusion, physician knowledge of CCTA results leads to improved alignment of aspirin and statin with the presence and severity of CAD although still many patients with CCTA-detected CAD are not discharged on aspirin or statin. Our findings suggest opportunity for practice improvement when CCTA is performed in the emergency department.

High Risk Plaque Features on Coronary CT Angiography

Coronary computed tomography angiography (CCTA) is a non-invasive imaging technique that can detect, characterize and quantify coronary atherosclerotic plaques in routine clinical settings. The distinct morphological features of vulnerable plaques and stable lesions provide an opportunity for CCTA to identify high-risk plaque features and guide stratified therapeutic interventions. Morphological plaque characteristics, such as large plaque volume, positive remodelling, low CT attenuation, spotty calcification and the napkin-ring sign have been linked to elevated risk of acute coronary syndrome. Recent advances in computational fluid dynamics enabled functional plaque assessment through endothelial shear stress and lesion specific fractional flow reserve calculation. The comprehensive, morphological and functional plaque assessment may improve the identification of vulnerable coronary lesions.

Hypertrophic Cardiomyopathy in a Monozygotic Twin Pair: Similarly Different.

A 70-year-old female patient was admitted to our hospital because of atypical chest pain and fatigue. No relevant diseases were recorded in her previous medical history. During the physical examination, she presented with a mild systolic murmur. Her 12-lead ECG indicated right bundle branch block (Figure 1A), and blood pressure was normal. Initial blood test showed normal hs-Troponin T and D-dimer levels. Transthoracic echocardiography (TTE) revealed mild concentric left ventricular (LV) hypertrophy (end-diastolic interventricular septal thickness 14 mm; LV mass index, 96 g/m2) with septal bulging and mild aortic stenosis (transaortic mean gradient 18 mm Hg, calculated aortic valve area 1.8 cm2) because of valve calcification (Figure 2A; Video I in the Data Supplement). In addition, TTE showed a good LV and right ventricular systolic function, impaired LV relaxation, and minimal mitral and tricuspidal regurgitation (Video II in the Data Supplement). To rule out obstructive coronary artery disease, we performed coronary artery calcium score scan and prospectively ECG-triggered coronary computed tomography angiography using a 256-slice multidetector-row computed tomography. The total coronary artery calcium score was 340; the calcium score of the aortic valve was 731 (Figure 3A). The coronary computed tomography angiography depicted a left dominant coronary system (Figure 4A) and several calcified and partially calcified atherosclerotic plaques along the left anterior descending coronary artery, causing moderate stenosis and partially calcified plaques in the left circumflex coronary artery, causing mild stenosis. The patient was discharged with optimized medications. Figure 1. Twelve-lead ECG indicated right bundle branch block in twin A and left ventricular strain pattern in twin B . Figure 2. M-mode echocardiography shows systolic anterior motion of the mitral valve in twin B (arrows), which is absent in twin A . Figure 3. Volume-rendered images of the aortic root show aortic valve …