Impact of aortic valve calcification severity and impaired left ventricular function on 3-year results of patients undergoing transcatheter aortic valve replacement

Objectives

To evaluate clinical pre-interventional predictors of 3-year outcome and mortality in high-risk patients with severe aortic valve stenosis treated with transcatheter aortic valve implantation (TAVI).

Methods

Among 367 patients included in the Aachen TAVI registry, 76 patients with baseline dual-source computed tomography (DSCT) for the quantification of aortic valve calcification (AVC) and a 3-year follow-up were identified.

Results

Survival at 30 days was 91 %, and it was 75 %, 66 % and 64 % at 1, 2 years and 3 years, respectively. Non-survivors at 3 years showed a significantly higher Agatston AVC score (2,854?±?1,651) than survivors (1,854?±?961, P?=?0.007). Multivariate analysis including age, logistic EuroScore, glomerular filtration rate, Agatston AVC score, ejection fraction?<?40 %, NYHA class, baseline medication, chronic lung disease and aortic regurgitation revealed that only the Agatston AVC score (P?=?0.03) and impaired left ventricular function (P?=?0.001) was significantly associated with mortality. Patients with Agatston AVC scores >2,000 had a significantly lower 3-year survival rate compared with patients with scores <2,000 (47 % vs 79 %, P?=?0.004).

Conclusions

In patients referred for TAVI, aortic valve calcification severity and impaired left ventricular function may serve as a predictor of long-term mortality. Therefore, AVC scores easily determined from pre-procedural CT datasets may be used for patient risk stratification.

Key Points

? Dual-source CT provides excellent valve delineation before transcatheter aortic valve implantation (TAVI). ? Aortic valve calcification assessed by cardiac CT predicts mortality in TAVI patients. ? Aortic valve calcification scores can help stratify high-risk patients for TAVI. ? Three-year results show good long-term outcome without evidence of structural valve deterioration.     

Novel connecting tube for saline chaser in contrast-enhanced CT: the effect of spiral flow of saline on contrast enhancement

Objective

To evaluate the effect of a newly developed connecting tube, which generates a spiral flow of saline, on aortic and hepatic contrast enhancement during hepatic-arterial phase (HAP) and portal venous phase (PVP) computed tomography (CT).

Methods

Eighty patients were randomly assigned to one of two protocols: with a new or a conventional tube. The contrast material (600 mgI/kg) was delivered over 30 s; this was followed by the administration of 25 ml saline solution delivered at the same injection rate as the contrast material. Unenhanced and contrast-enhanced CT images of the upper abdomen were obtained. We calculated the changes in the CT number (?HU) for the aorta during HAP and PVP, and for the liver during PVP. We compared ?HU between protocols.

Results

The mean ?HU for the abdominal aorta during HAP was significantly higher with the new tube protocol than with the conventional tube protocol (322?±?53 vs. 290?±?53, P?<?0.01). There were no significant differences in the mean ?HU for the abdominal aorta and liver during PVP between the two protocols (P?>?0.05).

Conclusion

The new connecting tube increased the effect of a saline chaser and significantly improved aortic enhancement during HAP.

Key Points

? Optimal administration of intravenous contrast material is essential for optimal CT quality. ? A new connecting tube can generate spiral flow, which improves intravenous administration. ? The new connecting tube improved aortic contrast enhancement during the hepatic-arterial phase. ? The new connecting tube increased the effect of a saline chaser.     

Chronic mitral regurgitation detected on cardiac MDCT: differentiation between functional and valvular aetiologies

Objective

To determine whether cardiac computed tomography (MDCT) can differentiate between functional and valvular aetiologies of chronic mitral regurgitation (MR) compared with echocardiography (TTE).

Methods

Twenty-seven patients with functional or valvular MR diagnosed by TTE and 19 controls prospectively underwent cardiac MDCT. The morphological appearance of the mitral valve (MV) leaflets, MV geometry, MV leaflet angle, left ventricular (LV) sphericity and global/regional wall motion were analysed. The coronary arteries were evaluated for obstructive atherosclerosis.

Results

All control and MR cases were correctly identified by MDCT. Significant differences were detected between valvular and control groups for anterior leaflet length (30?±?7 mm vs. 22?±?4 mm, P?<?0.02) and thickness (3.0?±?1 mm vs. 2.2?±?1 mm, P?<?0.01). High-grade coronary stenosis was detected in all patients with functional MR compared with no controls (P?<?0.001). Significant differences in those with/without MV prolapse were detected in MV tent area (?1.0?±?0.6 mm vs. 1.3?±?0.9 mm, P?<?0.0001) and MV tent height (?0.7?±?0.3 mm vs. 0.8?±?0.8 mm, P?<?0.0001). Posterior leaflet angle was significantly greater for functional MR (37.9?±?19.1° vs. 22.9?±?14°, P?<?0.018) and less for valvular MR (0.6?±?35.5° vs. 22.9?±?14°, P?<?0.017). Sensitivity, specificity, and positive and negative predictive values of MDCT were 100%, 95%, 96% and 100%.

Conclusion

Cardiac MDCT allows the differentiation between functional and valvular causes of MR.     

Postoperative pulmonary and aortic 3D haemodynamics in patients after repair of transposition of the great arteries

Objectives

To characterise aortic and pulmonary haemodynamics and investigate the correlation with post-surgical anatomy in patients with dextro-transposition of the great arteries (d-TGA).

Methods

Four-dimensional (4D) MRI was performed in 17 patients after switch repair of TGA and 12 healthy controls (age, 11.9?±?5.4 vs 23.3?±?1.6 years). Patients were divided according to the pulmonary trunk (TP) position in relation to the ascending aorta (AAo): anterior (n?=?10) and right/left anterior position (n?=?7). Analysis included visual grading (ranking 0–2) of pulmonary and aortic vortical and helical flow, flow velocity quantification, blood-flow distribution to the right and left pulmonary arteries (flow ratio rPA:lPA), and vessel lumen areas.

Results

Anterior TP position was associated with increased vortices in six out of ten patients compared with right anterior TP position (one out of seven) and controls (none). Reduced systolic lPA and TP lumina in patients resulted in significantly increased peak systolic velocities (P?<?0.001). Flow ratio rPA:lPA was more heterogeneous in patients (rPA:lPA?=?1.56?±?0.78 vs volunteers 1.09?±?0.15; P?<?0.05) with predominant flow to the rPA. Eleven patients presented increased helices in the AAo (grade 1.6).

Conclusions

Evaluation of post-surgical haemodynamics in TGA patients revealed increased vortical flow for anterior TP position, asymmetric flow and increased systolic flow velocity in the pulmonary arteries owing to reduced vascular lumina.

Key Points

? 3D phase contrast MRI with velocity encoding (4D MRI) has numerous cardiovascular applications ? 4D MRI demonstrates postoperative haemodynamics following surgery for transposition of the great arteries ? Flow visualisation depicted enhanced pulmonary vortices in the anterior pulmonary trunk ? Narrow pulmonary arterial systolic lumina resulted in increased peak systolic velocities     

Effect of carotid artery stenting on cerebral blood flow: evaluation of hemodynamic changes using arterial spin labeling

Introduction

The purpose of this work was to quantitatively evaluate the hemodynamic changes after carotid artery stenting (CAS) by measuring cerebral blood flow (CBF) using arterial spin labeling (ASL).

Methods

Twenty sets of pre- and postprocedural CBF maps were acquired using ASL in patients who underwent CAS. Vascular territory- and anatomical structure-based regions of interest were applied to the CBF maps. Relative CBF (rCBF) was calculated by adjusting ipsilateral CBF with contralateral CBF. To assess the changes in rCBF after CAS (ΔrCBF), we calculated the following difference: $ \Delta\mathrm{rCBF}=\mathrm{rCB}{{\mathrm{F}}_{\mathrm{postprocedural}}}-\mathrm{rCB}{{\mathrm{F}}_{\mathrm{preprocedural}}} $ .

Results

Postprocedural CBFs were significantly higher than preprocedural CBFs for internal carotid artery and middle cerebral artery territories (P?<?0.05 in both). Postprocedural rCBFs were also significantly higher than preprocedural rCBFs for internal carotid artery and middle cerebral artery territories (P?<?0.05 in both). Significant correlations were observed between preprocedural rCBF and ΔrCBF for the internal carotid artery and middle cerebral artery territories (r?=??0.7211, P?=?0.0003 and r?=??0.6427, P?=?0.0022, respectively). Areas in which the ΔrCBF values were >5.00 ml?100 g^?1 min^?1 were the precentral, postcentral, middle frontal, middle temporal (caudal), superior parietal, and angular gyri.

Conclusions

ASL has potential as a noninvasive imaging tool for the quantitative evaluation of hemodynamic changes after CAS. CAS improves cerebral perfusion in patients with carotid artery stenosis, and patients with greater perfusion deficits prior to CAS have greater improvement in perfusion after CAS. In addition, eloquent areas show the greatest improvement in perfusion.     

Anomalous origin of the coronary artery from the wrong coronary sinus evaluated with computed tomography: “High-risk” anatomy and its clinical relevance

Objective

The aim of the study was to assess coronary arteries arising from the wrong coronary sinus, including CT-evaluated high-risk anatomic features, clinical symptoms and cardiac events during follow-up.

Methods

A total of 7,115 patients scheduled for 64-slice or dual-source cardiac CT were screened for the presence of isolated anomalous origin of the coronary artery from the wrong coronary sinus.

Results

Anomalous origin of the coronary artery was found in 54 (0.76 %) patients (29 men, 25 women, mean age 60.9?±?11.6 years). Sixteen (30 %) patients with abnormal right coronary origin (ARCA) more commonly had a slit-like orifice (15 vs. 3; p?p?p?p?=?0.03). Patients with ARCA tended to show higher occurrence of cardiac events in the follow-up than individuals with ALCA and ALCx (5 vs. 4; p?=?NS).

Conclusions

High-risk anatomy features are most common in patients with ARCA and these patients also have higher prevalence of chest pain and cardiac events in the follow-up than individuals with ALCA and ALCx.

Key Points

? Multislice computed tomography enables detection and evaluation of the coronary artery anomalies. ? Anomalous anatomy of the coronary artery potentially influences the prevalence of adverse events. ? Adverse events tend to be most common in anomalous right coronary arteries.     

Appendiceal length as an independent risk factor for acute appendicitis

Objectives

To determine if appendiceal lengths differ between adults with acute appendicitis and asymptomatic controls.

Methods

In vivo appendiceal length at computed tomography (CT) in 321 adults with surgically proven appendicitis was compared with that in 321 consecutive asymptomatic adult controls. CT length was derived using curved multiplanar reformats along the long axis. Gross pathological length provided external validation for appendectomy cases.

Results

Appendiceal length at CT correlated well with appendicitis specimens (mean length, 6.8 cm vs 6.6 cm; 79 % within 1.5 cm). For asymptomatic controls, mean CT appendiceal length was 7.9 cm, longer in men (8.4?±?3.8 vs 7.4?±?3.1 cm; P?=?0.02), matching closely historical normative post-mortem data. The mean and standard deviation of appendiceal length at CT were significantly greater among negative controls than in the positive appendicitis group (7.9?±?3.5 vs 6.8?±?1.9 cm; P?=?0.03). Of appendicitis cases, 90 % (288/321) fell within the range 4.0–10.0 cm, compared with 59 % (189/321) of negative controls (P?<?0.001). Among controls, a fivefold increase in appendixes >10 cm and a twofold increase in appendixes <4 cm were observed. Half (9/18) of long appendicitis cases showed tip appendicitis at CT.

Conclusions

“Intermediate” appendiceal lengths (4–10 cm) are more frequently complicated by acute appendicitis, whereas both “long” (>10 cm) and “short” (<4 cm) lengths are more frequently observed in unaffected adults.

Key Points

? “Long” (>10 cm) appendices are more frequently observed in asymptomatic adults. ? In cases of acute appendicitis, 90 % measure 4–10 cm in length. ? Measurement of appendiceal length at computed tomography correlates well with gross pathology. ? Tip appendicitis is more common among long appendixes.     

Ascending aorta dilatation in patients with bicuspid aortic valve stenosis: a prospective CMR study

Background

The aim of this study was to evaluate the natural progression of aortic dilatation and its association with aortic valve stenosis (AoS) in patients with bicuspid aortic valve (BAV).

Methods

Prospective study of aorta dilatation in patients with BAV and AoS using cardiac magnetic resonance (CMR). Aortic root, ascending aorta, aortic peak velocity, left ventricular systolic and diastolic function and mass were assessed at baseline and at 3-year follow-up.

Results

Of the 33 enrolled patients, 5 needed surgery, while 28 patients (17 male; mean age: 31?±?8 years) completed the study. Aortic diameters significantly increased at the aortic annulus, sinus of Valsalva and tubular ascending aorta levels (P?<?0.050). The number of patients with dilated tubular ascending aortas increased from 32 % to 43 %. No significant increase in sino-tubular junction diameter was observed. Aortic peak velocity, ejection fraction and myocardial mass significantly increased while the early/late filling ratio significantly decreased at follow-up (P?<?0.050). The progression rate of the ascending aorta diameter correlated weakly with the aortic peak velocity at baseline (R ²?=?0.16, P?=?0.040).

Conclusion

BAV patients with AoS showed a progressive increase of aortic diameters with maximal expression at the level of the tubular ascending aorta. The progression of aortic dilatation correlated weakly with the severity of AoS.

Key Points

? Bicuspid aortic valve (BAV) is the most common congenital heart defect. ? BAV patients have an increased risk of developing aortic valve stenosis (AoS). ? BAV patients have an increased risk of developing thoracic aorta dilatation. ? The severity of aortic stenosis is correlated to the progression of aortic dilatation. ? Cardiac magnetic resonance can rapidly assess patients with a bicuspid aortic valve.     

Diagnostic accuracy of 128-slice dual-source CT coronary angiography: a randomized comparison of different acquisition protocols

Objectives

To compare the diagnostic performance and radiation exposure of 128-slice dual-source CT coronary angiography (CTCA) protocols to detect coronary stenosis with more than 50 % lumen obstruction.

Methods

We prospectively included 459 symptomatic patients referred for CTCA. Patients were randomized between high-pitch spiral vs. narrow-window sequential CTCA protocols (heart rate below 65 bpm, group A), or between wide-window sequential vs. retrospective spiral protocols (heart rate above 65 bpm, group B). Diagnostic performance of CTCA was compared with quantitative coronary angiography in 267 patients.

Results

In group A (231 patients, 146 men, mean heart rate 58?±?7 bpm), high-pitch spiral CTCA yielded a lower per-segment sensitivity compared to sequential CTCA (89 % vs. 97 %, P?=?0.01). Specificity, PPV and NPV were comparable (95 %, 62 %, 99 % vs. 96 %, 73 %, 100 %, P?>?0.05) but radiation dose was lower (1.16?±?0.60 vs. 3.82?±?1.65 mSv, P?<?0.001). In group B (228 patients, 132 men, mean heart rate 75?±?11 bpm), per-segment sensitivity, specificity, PPV and NPV were comparable (94 %, 95 %, 67 %, 99 % vs. 92 %, 95 %, 66 %, 99 %, P?>?0.05). Radiation dose of sequential CTCA was lower compared to retrospective CTCA (6.12?±?2.58 vs. 8.13?±?4.52 mSv, P?<?0.001). Diagnostic performance was comparable in both groups.

Conclusion

Sequential CTCA should be used in patients with regular heart rates using 128-slice dual-source CT, providing optimal diagnostic accuracy with as low as reasonably achievable (ALARA) radiation dose.

Key Points

? 128-slice dual-source CT coronary angiography offers several different acquisition protocols. ? Randomized comparison of protocols reveals an optimal protocol selection strategy. ? Appropriate CTCA protocol selection lowers radiation dose, while maintaining high quality. ? CTCA protocol selection should be based on individual patient characteristics. ? A prospective sequential protocol is preferred for CTCA.     

Evaluation of 100 brain examinations using a 3 Tesla MR-compatible incubator—safety, handling, and image quality

Introduction

Several studies have revealed the importance of brain imaging in term and preterm infants. The aim of this retrospective study was to review safety, handling, and image quality of MR brain imaging using a new 3 Tesla MR-compatible incubator.

Methods

Between 02/2011 and 05/2012 100 brain MRIs (84 infants, mean gestational age 32.2?±?4.7 weeks, mean postmenstrual age at imaging 40.6?±?3.4 weeks) were performed using a 3 Tesla MR-compatible incubator with dedicated, compatible head coil. Seventeen examinations (13 infants, mean gestational age 35.1?±?5.4 weeks, mean postmenstrual age at imaging 47.8?±?7.4 weeks) with a standard head coil served as a control. Image analysis was performed by a neuroradiologist and a pediatric radiologist in consensus.

Results

All but two patients with known apnea were transferred to the MR unit and scanned without problems. Handling was easier and faster with the incubator; relevant motion artifacts (5.9 vs. 10.8 %) and the need for repetitive sedation (43.0 vs. 86.7 %) were reduced. Considering only images not impaired by motion artifacts, image quality (4.8?±?0.4 vs. 4.3?±?0.8, p?=?0.047) and spatial resolution (4.7?±?0.4 vs. 4.2?±?0.6, p?=?0.011) of T2-weighted images were scored significantly higher in patients imaged with the incubator. SNR increased significantly (171.6?±?54.5 vs. 80.5?±?19.8, p?<?0.001) with the use of the incubator.

Conclusion

Infants can benefit from the use of a 3 Tesla MR-compatible incubator because of its safety, easier, and faster handling (compared to standard imaging) and possibility to obtain high-quality MR images even in unstable patients.     

Severe aortic arch calcification depicted on chest radiography strongly suggests coronary artery calcification

Objective

To evaluate the association between aortic arch calcifications (AAC) on chest radiography and coronary artery calcium (CAC) score determined by CT.

Methods

A total of 128 patients (75 men; 69.3?±?14.7 years) who underwent chest radiography and CAC scoring at CT were included in this retrospective analysis. The extent of AAC on chest radiography was evaluated independently by two blinded observers using a semi-quantitative four-point scale (0–3). Intra- and interobserver agreement was assessed by weighted ? statistics. Amount of AAC determined on radiography was correlated with CAC and ROC analyses performed to characterise the diagnostic performance of AAC grading.

Results

Excellent intraobserver (??=?0.82) and good interobserver (??=?0.75) agreement of AAC grading was noted. Moderate agreement (??=?0.46, 95 % CI 0.36–0.56) with a linear trend (P?<?0.0001) between AAC grades and CAC scores was found. Cut-off between AAC grades 0–2 and 3 had a sensitivity of 38.6 %, specificity of 96.4 %, PPV of 85.0 %, NPV of 75.0 % and accuracy of 76.6 % for the correct identification of CAC scores greater than 400.

Conclusion

Semi-quantitative AAC grading on chest radiography is reliable and positively associated with CAC scoring. We propose to report the extent of AAC in comprehensive radiological reports as “not present”, “moderate” or “severe”, as severe AAC strongly suggests coronary artery calcification.

Key Points

? Semi-quantitative aortic arch calcification (AAC) grading on plain chest radiography appears reliable. ? AAC grading is positively associated with CT coronary artery calcium scoring. ? AAC grading has a high specificity for ruling out CAC scores greater than 400. ? We propose the reporting of the extent of AAC grade in chest X-ray (CXR) reports.     

Defining predictors for long progression-free survival after radioembolisation of hepatic metastases of neuroendocrine origin

Objectives

To define predictive parameters of long progression-free survival (PFS) in patients undergoing radioembolisation of neuroendocrine liver metastases.

Methods

The following clinical and magnetic resonance imaging (MRI) parameters of 45 radioembolised patients (median age, 62 years; range, 43–75) were reviewed: age, gender, levels of chromogranin A and neuron-specific enolase (NSE), primary tumour site, Ki-67 proliferation index, hepatic tumour load, number of metastases, signal intensity characteristics, vascularisation, haemorrhagic and necrotic transformation and fluid–fluid levels. PFS was assessed according to RECIST 1.0. Statistical analysis included univariate Cox regression, Kaplan–Meier and multivariate regression.

Results

Median PFS was 727 days (95 % CI, 378–964). In the univariate regression analysis, hypovascular metastases progressed earlier (111 vs 727 days; P?<?0.05). A Ki-67 ≤2 % was associated with a longer PFS than a Ki-67 of 3–20 % or >20 % (911 vs 727 vs 210 days, respectively; P?<?0.05). Low NSE predicted longer PFS (911 vs 378 days; P?<?0.05). In the adjusted multivariate analysis, vascularisation (hypervascularisation vs. no hypervascularisation; P?=?0.0009) and NSE level (low vs high; P?=?0.0119) had the strongest influence on PFS.

Conclusion

Response to radioembolisation in patients with neuroendocrine liver metastases can be predicted by the metastatic vascularisation pattern, the NSE level and the Ki-67.

Key Points

? Radioembolisation is an effective treatment in hepatic metastases of neuroendocrine origin. ? Pre-therapeutic vascularisation patterns of metastases on MRI can predict long progression-free survival. ? Assessment of pre-therapeutic markers provides better therapy planning.     

Dose reduction in dynamic CT stress myocardial perfusion imaging: comparison of 80-kV/370-mAs and 100-kV/300-mAs protocols

Objectives

To determine the effect of reduced 80-kV tube voltage with increased 370-mAs tube current on radiation dose, image quality and estimated myocardial blood flow (MBF) of dynamic CT stress myocardial perfusion imaging (CTP) in patients with a normal body mass index (BMI) compared with a 100-kV and 300-mAs protocol.

Methods

Thirty patients with a normal BMI (<25 kg/m²) with known or suspected coronary artery disease underwent adenosine-stress dual-source dynamic CTP. Patients were randomised to 80-kV/370-mAs (n?=?15) or 100-kV/300-mAs (n?=?15) imaging. Maximal enhancement and noise of the left ventricular (LV) cavity, contrast-to-noise ratio (CNR) and MBF of the two groups were compared.

Results

Imaging with 80-kV/370-mAs instead of 100-kV/300-mAs was associated with 40 % lower radiation dose (mean dose–length product, 359?±?66 vs 628?±?112 mGy?cm; P?<?0.001 ) with no significant difference in CNR (34.5?±?13.4 vs 33.5?±?10.4; P?=?0.81) or MBF in non-ischaemic myocardium (0.95?±?0.20 vs 0.99?±?0.25 ml/min/g; P?=?0.66). Studies obtained using 80-kV/370-mAs were associated with 30.9 % higher maximal enhancement (804?±?204 vs 614?±?115 HU; P?<?0.005), and 31.2 % greater noise (22.7?±?3.5 vs 17.4?±?2.6; P?<?0.001).

Conclusions

Dynamic CTP using 80-kV/370-mA instead of 100-kV/300-mAs allowed 40 % dose reduction without compromising image quality or MBF. Tube voltage of 80-kV should be considered for individuals with a normal BMI.

Key Points

? CT stress perfusion imaging (CTP) is increasingly used to assess myocardial function. ? Dynamic CTP is feasible at 80-kV in patients with normal BMI. ? An 80-kV/370-mAs protocol allows 40 % dose reduction compared with 100-kV/300-mAs. ? Contrast-to-noise ratio and myocardial blood flow of the two protocols were comparable.     

Optimal table feed in run-off CT angiography in patients with abdominal aortic aneurysms

Objectives

To assess the influence of different table feeds (TFs) on vascular enhancement and image quality in patients with an abdominal aortic aneurysm (AAA) undergoing computed tomography (CT) angiography of the lower extremities (run-off CTA).

Methods

Seventy-nine patients (71?±?8 years) with an AAA (>30 mm) who underwent run-off CTA between January 2004 and August 2011 were included in this retrospective institutional review board-approved study. Run-off CTA was conducted using 16- and 64-row CT. The range of TFs was 30–86 mm/s and was categorised in quartiles TF1 (32.6?±?1.9 mm/s), TF2 (38.9?±?0.9 mm/s), TF3 (43.9?±?3.1 mm/s) and TF4 (57.4?±?10.5 mm/s). Image quality was rated independently by two radiologists and vessel enhancement was assessed.

Results

Image quality was diagnostic at all aortic, pelvic and almost all thigh levels. Below the knee, the number of diagnostic levels was highest for TF1 and decreased to TF4. Arterial enhancement between the aorta and fibular trunk was not different in all TF groups, P?>?0.05. At the calf and foot strongest arterial enhancement was noted for TF1 and TF2 and decreased to TF4, P?<?0.01.

Conclusion

Results indicate that the highest image quality of run-off CTA in patients with an AAA may be obtained using table feeds measuring 30–35 mm/s.

Key Points

? CTA has become a key investigation for peripheral vascular disease. ? Run-off CTA is more complex in patients with an abdominal aortic aneurysm. ? Run-off CTA is feasible with a short bolus of intravenous contrast medium. ? A constant 30–35 mm/s table feed provides the highest likelihood of diagnostic images.     

The value of time-intensity curves obtained after microbubble contrast agent injection to discriminate responders from non-responders to anti-inflammatory medication among patients with Crohn’s disease

Objective

To assess the value of time-intensity curves obtained after sulphur hefluoride-filled microbubble contrast agent injection to discriminate responders from non-responders among patients with Crohn’s disease (CD).

Methods

Forty-three patients (29 male and 14 female; mean age?±?SD, 48.5?±?17.17 years) with initial diagnosis of active CD were recruited. In each patient, the therapeutic outcome was assessed after 12 weeks from the beginning of pharmacologic treatment. The terminal ileal loop was scanned after sulphur hexafluoride-filled microbubble injection, and the digital cine-clip registered during the first-pass dynamic enhancement was quantified in gray-scale levels. The percentage of maximal enhancement, time to peak enhancement, and area under the time-intensity curve in responders vs. non-responders were compared by Mann-Whitney U non-parametric test.

Results

Responders (n?=?25 patients) vs. non-responders (n?=?18) differed in the area under the time-intensity curve (621.58?±?374.53 vs. 1,199.64?±?386.39 P?<?0.05), while they did not differ in percentage of maximal enhancement (41.26?±?15.22 vs. 43.17?±?4.41, P?=?0.25) and time to peak enhancement (11.31?±?3.06 vs. 10.12?±?3.47, P?=?0.15).

Conclusions

The area under the time-intensity curve obtained after microbubble injection was the only parameter to discriminate responders from non-responders among patients with CD during pharmacologic treatment.

Key Points

? Dynamic ultrasound using microbubble contrast agents can help assess inflammatory bowel disease ? Time-intensity curves can assess therapeutic outcome in Crohn’s disease (CD) ? The area under the time-intensity curve differentiates responders from non-responders during pharmacological treatment     

Salvage assessment with cardiac MRI following acute myocardial infarction underestimates potential for recovery of systolic strain

Objectives

Our aim was to evaluate the relationship between the degree of salvage following acute ST elevation myocardial infarction (STEMI) and subsequent reversible contractile dysfunction using cardiac magnetic resonance (CMR) imaging.

Methods

Thirty-four patients underwent CMR examination 1–7 days after primary percutaneous coronary intervention (PPCI) for acute STEMI with follow-up at 1 year. The ischaemic area-at-risk (AAR) was assessed with T2-weighted imaging and myocardial necrosis with late gadolinium enhancement. Myocardial strain was quantified with complementary spatial modulation of magnetisation (CSPAMM) tagging.

Results

Ischaemic segments with poor (<25 %) or intermediate (26–50 %) salvage index were associated with worse Eulerian circumferential (Ecc) strain immediately post-PPCI (?9.1 %?±?0.6, P?=?0.033 and ?11.8 %?±?1.3, P?=?0.003, respectively) than those with a high (51–100 %) salvage index (?14.4 %?±?1.3). Mean strain in ischaemic myocardium improved between baseline and follow-up (?10.1 %?±?0.5 vs. ?16.2 %?±?0.5 %, P?<?0.0001). Segments with poor salvage also showed an improvement in strain by 1 year (?9.1 %?±?0.6 vs. ?15.3 %?±?0.6, P?=?0.033) although they remained the most functionally impaired.

Conclusions

Partial recovery of peak systolic strain following PPCI is observed even when apparent salvage is less than 25 %. Late gadolinium enhancement (LGE) may not equate to irreversibly injured myocardium and salvage assessment performed within the first week of revascularisation may underestimate the potential for functional recovery.

Key Points

? MRI can measure how much myocardium is damaged after a heart attack. ? Heart muscle that appears initially non-viable may sometimes partially recover. ? Enhancement around the edges of infarcts may resolve over time. ? Evaluating new cardio-protective treatments with MRI requires appreciation of its limitations.     

Quantification and characterisation of coronary artery plaque volume and adverse plaque features by coronary computed tomographic angiography: a direct comparison to intravascular ultrasound

Objective

We evaluated the performance of manual measures of coronary plaque volumes and atherosclerotic plaque features from coronary CT angiography (CTA), using intravascular ultrasound (IVUS) as the reference.

Methods

Thirty individual coronary plaques with suitable fiduciary markers were identified. Plaque volumes on coronary CTA were manually quantified by two observers and compared to IVUS plaque volumes as interpreted by an independent laboratory. The presence of adverse plaque characteristics—low attenuation plaque (LAP), positive remodelling (PR) and spotty calcification (SC)—on coronary CTA was evaluated and compared to IVUS.

Results

High correlation in plaque volumes was detected between observers (r?=?0.94, P?<?0.0001; 95 % limits of agreement <48.7 mm³, bias 6.6 mm³). Excellent correlation (r?=?0.95, P?<?0.0001) was noted in plaque volume between independent observers and IVUS (95 % limits of agreement <40.6 mm³, bias ?4.4 mm³) and did not differ from IVUS (105.0?±?56.7 vs. 109.4?±?60.7 mm³, P?=?0.2). The frequency of LAP (10 % vs. 17 %), PR (7 % vs. 10 %) and SC (27 % vs. 33 %) was similar between coronary CTA and IVUS (all P?=?NS).

Conclusions

Plaque volume on coronary CTA determined by manual methods demonstrates high correlation and modest agreement to IVUS. Further, coronary CTA demonstrates high accuracy for the identification of adverse plaque characteristics, including LAP, PR and SC.

Key Points

? Coronary CT angiography is a non-invasive test that enables coronary plaque assessment ? Plaque quantification by coronary CT angiography correlates well with intravascular ultrasound findings ? Coronary CT angiography can identify adverse plaque characteristics     

Calcium at the carotid siphon as an indicator of internal carotid artery stenosis

Objectives

Carotid siphon calcification is often visible on unenhanced head CT (UCT), but the relation to proximal carotid artery stenosis (CAS) is unclear. We investigated the association of carotid siphon calcification with the presence of CAS.

Methods

This IRB-waived retrospective study included 160 consecutive patients suspected of stroke (age 64?±?14 years, 63 female) who underwent head UCT and CTA of the head and neck. CAS was rated on CTA as not present or present with non-significant (<50 %), moderate (50–69 %) or significant (≥70 %) stenosis. Presence, shape (on UCT) and volume (on CTA) of carotid siphon calcifications were related to CAS.

Results

Carotid siphon calcification was absent in 41 % of patients and bilateral in 94 % of those with calcifications. Presence, shape and volume of calcification resulted in odds ratios for having significant CAS of 10.1, 3.9 and 8.4, with 95 % CIs of 1.3–79.6, 1.1–14.1 and 2.6–26.8, respectively. Corresponding NPVs were 0.98, 0.98 and 0.96, while PPVs were 0.14, 0.07 and 0.29, respectively.

Conclusion

Absence of calcification in the carotid artery siphon on UCT has high negative predictive value for carotid artery stenosis in patients with suspected stroke. However, siphon calcification is not a reliable indicator of significant carotid artery stenosis.

Key Points

? Many stroke patients do not have calcification in the carotid artery siphon. ? Carotid stenosis ≥50?% is unlikely in stroke patients without siphon calcification. ? Carotid siphon calcium is a poor indicator of significant carotid artery stenosis.     

Evaluation of malposition of the branch pulmonary arteries using cardiovascular computed tomography angiography

Objectives

To analyze 15 cases of malposition of branch pulmonary arteries (MBPA) for the hospital-based prevalence, clinical information, surgical outcome, imaging findings, associated cardiovascular and airway abnormalities on cardiovascular computed tomography angiography (CCTA).

Methods

We retrospectively searched for patients with MBPA from our database consisting of patients referred for CCTA due to known or suspected congenital heart disease and also from all patients receiving chest computed tomography (CT) during the same time period. We analyzed the hospital-based prevalence, image findings, associated cardiovascular anomalies, airway compression, and recorded the clinical information and surgical outcome.

Results

Our study showed 15 patients with MBPA (hospital-based prevalence: 0.33 % among patients with congenital heart disease and 0.06 % in all patients receiving chest CT or CCTA). Classic type was more common than lesser type (67 % versus 33 %). All patients had associated cardiovascular anomalies, including aortic arch abnormalities (80 %) and secondary airway compression (33 %). Surgery was performed in 67 % of cardiovascular anomalies and 60 % of airway stenoses.

Conclusions

MBPA has a hospital-based prevalence of 0.33 % among patients with congenital heart disease and 0.06 % in all patients receiving either chest CT or CCTA. CCTA can delineate the anatomy of MBPA, associated cardiovascular and airway abnormalities for preoperative evaluation.

Key Points

? MBPA has a hospital-based prevalence of 0.33 % among congenital heart disease patients. ? Classic type of MBPA was more common than lesser type. ? All MBPA patients had associated cardiovascular anomalies, 33 % had secondary airway compression. ? CCTA delineates the anatomy of MBPA, associated cardiovascular and airway abnormalities. ? CCTA is beneficial in MBPA for preoperative evaluation and planning.     

Reproducibility of aortic annulus measurements by computed tomography

Objectives

To evaluate a systematic approach for measurement of aortic annulus dimensions by cardiac computed tomography.

Methods

CT data sets of 64 patients were evaluated. An oblique cross-section aligned with the aortic root was created by systematically identifying the caudal insertion points of the three aortic cusps and sequentially aligning them in a double oblique plane. Aortic annulus dimensions, distances of coronary ostia and a suitable fluoroscopic projection angle were independently determined by two observers.

Results

Interobserver intraclass correlation coefficients (ICC) for aortic annulus diameters were excellent (ICC 0.89–0.93). Agreement for prosthesis size selection was excellent (??=?0.86 for mean, ??=?0.84 for area-derived and ??=?0.91 for circumference-derived diameter). Mean distances of the left/right coronary ostium were 13.4?±?2.4/14.4?±?2.8 mm for observer 1 and 13.2?±?2.7/13.5?±?3.2 mm for observer 2 (p?=?0.30 and p?=?0.0001, respectively; ICC 0.76/0.77 for left/right coronary artery). A difference of less than 10° for fluoroscopic projection angle was achieved in 84.3 % of patients.

Conclusions

A systematic approach to generate a double oblique imaging plane exactly aligned with the aortic annulus demonstrates high interobserver and intraobserver agreements for derived measurements which are not influenced by aortic root calcification.

Key Points

? Systematic approach to generate a double oblique imaging plane for TAVI evaluation. ? This method is straightforward and software independent. ? An approach with high reproducibility, not influenced by aortic root calcification.