Predictors and neurological consequences of periprocedural cerebrovascular events following transcatheter aortic valve implantation with self-expanding valves.

Aims: To evaluate the patient- and procedure-related predictors of transcatheter aortic-valve implantation (TAVI)-associated ischemic brain lesions and to assess the effect of silent cerebral ischemic lesions (SCIL) on neurocognitive function. Methods and results: We investigated 113 consecutive patients with severe aortic stenosis who underwent brain magnetic resonance imaging (MRI) within a week following TAVI. To assess periprocedural cerebral ischemic lesions, diffusion-weighted MRI was utilized. We used multivariate linear regression to identify the independent predictors of TAVI-related ischemic lesion volume (ILV) and periprocedural stroke. Neurocognitive evaluation was performed before and following TAVI at 6-month and one-year follow-up. Following TAVI, a total of 944 new cerebral ischemic lesions were detected in 104 patients (92%). The median ILV was 257 µl (interquartile range [IQR]:97.1-718.8µl) with a median lesion number of 6/patient [IQR:2-10]. The majority of ischemic lesions were clinically silent (95%), while 5% of the lesions induced a stroke, which was confirmed by MRI. Predilatation (ß = 1.13[95%CI:0.32-1.93], p = 0.01) and the number of valve positioning attempts during implantation (ß = 0.28[95%CI:0.06-0.50], p = 0.02) increased the log-transformed total ILV. Predilatation (OR = 12.04[95%CI:1.46-99.07], p = 0.02) and alternative access routes (OR = 7.84[95%CI:1.01-61.07], p = 0.02) were associated with stroke after adjustments for comorbidities and periprocedural factors. The presence of SCILs were not associated with a change in neurocognitive function that remained stable during the one-year follow-up. Conclusion: While periprocedural ischemic lesions are frequent, most of them are clinically silent and might not impact the patients' neurocognitive function. The number of valve positioning attempts, predilatation, and alternative access routes should be taken into consideration during TAVI to reduce the ILV and risk for stroke.

Subclinical leaflet thrombosis after transcatheter aortic valve implantation is associated with silent brain injury on brain magnetic resonance imaging.

AIMS: Whether hypoattenuated leaflet thickening (HALT) following transcatheter aortic valve implantation (TAVI) carries a risk of subclinical brain injury (SBI) is unknown. We investigated whether HALT is associated with SBI detected on magnetic resonance imaging (MRI), and whether post-TAVI SBI impacts the patients' cognition and outcome. METHODS AND RESULTS: We prospectively enrolled 153 patients (age: 78.1 ± 6.3 years; female 44%) who underwent TAVI. Brain MRI was performed shortly post-TAVI and 6 months later to assess the occurrence of acute silent cerebral ischaemic lesions (SCIL) and chronic white matter hyperintensities (WMH). HALT was screened by cardiac computed tomography (CT) angiography (CTA) 6 months post-TAVI. Neurocognitive evaluation was performed before, shortly after and 6 months following TAVI. At 6 months, 115 patients had diagnostic CTA and 10 had HALT. HALT status, baseline, and follow-up MRIs were available in 91 cases. At 6 months, new SCIL was evident in 16%, new WMH in 66%. New WMH was more frequent (100 vs. 62%; P = 0.047) with higher median volume (319 vs. 50 mm3; P = 0.039) among HALT-patients. In uni- and multivariate analysis, HALT was associated with new WMH volume (beta: 0.72; 95%CI: 0.2-1.39; P = 0.009). The patients' cognitive trajectory from pre-TAVI to 6 months showed significant association with the 6-month SCIL volume (beta: -4.69; 95%CI: -9.13 to 0.27; P = 0.038), but was not related to the presence or volume of new WMH. During a 3.1-year follow-up, neither HALT [hazard ratio (HR): 0.86; 95%CI: 0.202-3.687; P = 0.84], nor the related WMH burden (HR: 1.09; 95%CI: 0.701-1.680; P = 0.71) was related with increased mortality. CONCLUSIONS: At 6 months post-TAVI, HALT was linked with greater WMH burden, but did not carry an increased risk of cognitive decline or mortality over a 3.1-year follow-up (NCT02826200).

Microstructural alterations measured by diffusion tensor imaging following transcatheter aortic valve replacement and their association with cerebral ischemic injury and cognitive function - a prospective study.

PURPOSE: We assessed diffusion tensor imaging (DTI) metric changes of the corpus callosum and cingulum correlated to postprocedural ischemic lesion load (ILL) and cognitive performance in transcatheter aortic valve replacement (TAVR). METHODS: TAVR subjects had DTI post-TAVR (≤ 8 days) and at 6 months (78 participants, males 56%, age 78.8 years ± 6.3) and four neurocognitive tests (pre-TAVR, post-TAVR, 6 months, 1 year). DTI metrics (fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD)) were calculated for 7 regions: corpus callosum (genu, body, splenium) and cingulum (cingulate gyrus, parahippocampal cingulum bilaterally). DTI metrics post-TAVR and at 6 months were compared with Student's t-test (p < 0.0071) and ANOVA covarying for sex, ILL (p < 0.05) with post hoc analysis of ILL groups (p < 0.0167). Repeated-measures linear mixed-effect model (p < 0.05) was performed to investigate the effect of time and ILL on cognition. RESULTS: At 6 months, significant decrease of the following DTI metrics was detected: AD (genu, body, splenium, right parahippocampal cingulum: p ≤ 0.0046); MD (body, both cingulate gyri: p ≤ 0.0050); RD (left cingulate gyrus: p = 0.0021); FA (splenium: p < 0.0001). ANOVA confirmed significant effect of female sex on AD + MD reduction (body, right cingulate gyrus) and AD reduction (left cingulate gyrus) (p ≤ 0.0254). Significant negative effect of ILL on some DTI metric changes was found (AD + MD-body: p ≤ 0.0050; MD-left cingulate gyrus: p = 0.0087). Cognitive performance remained stable with significant negative correlation of ILL and retrograde memory and visual scores (p ≤ 0.0483). CONCLUSION: Significant effect of TAVR on cerebral microstructural integrity was found with reduced diffusivities opposite to the trends reported in various neurodegenerative conditions/ageing, notably in women and lower ILL, and with preserved/improved cognition. TRIAL REGISTRATION NUMBER: NCT02826200 at ClinicalTrials.gov; date of registration: 07. July 2016.

The Predictive Value of Left Atrial Strain Following Transcatheter Aortic Valve Implantation on Anatomical and Functional Reverse Remodeling in a Multi-Modality Study.

Introduction: Transcatheter aortic valve implantation (TAVI) can improve left ventricular (LV) mechanics and survival. Data on the predictive value of left atrial (LA) strain following TAVI are scarce. We aimed to evaluate the association of LA strain measured shortly post-TAVI with functional and anatomical reverse remodeling of the LA and LV, and its association with mortality. Methods: We prospectively investigated 90 patients who underwent TAVI. Transthoracic echocardiography including strain analysis was performed shortly after TAVI and repeated 6 months later. CT angiography (CTA) was performed for pre-TAVI planning and 6 months post-TAVI. Speckle tracking echocardiography was used to determine LA peak reservoir strain (LASr) and LV global longitudinal strain (LV-GL), LA volume index (LAVi) was measured by TTE. LV mass index (LVMi) was calculated using CTA images. LA reverse remodeling was based on LASr and LAVi changes, whereas LV reverse remodeling was defined as an improvement in LV-GLS or a reduction of LVMi. The association of severely reduced LASr (<20%) at baseline with changes (Δ) in LASr, LAVi, LV-GLS and LVMi were analyzed using linear regression, and Cox proportional hazard model for mortality. Results: Mean LASr and LV-GLS were 17.7 ± 8.4 and -15.3 ± 3.4% at baseline and 20.2 ± 10.2 and -16.6 ± 4.0% at follow-up (p = 0.024 and p < 0.001, respectively). Severely reduced LASr at baseline was associated with more pronounced ΔLASr (ß = 5.24, p = 0.025) and LVMi reduction on follow-up (ß = 5.78, p = 0.036), however, the majority of the patients had <20% LASr on follow-up (44.4%). Also, ΔLASr was associated with ΔLV-GLS (adjusted ß = 2.10, p < 0.001). No significant difference in survival was found between patients with baseline severely reduced LASr (<20%) and higher LASr (≥20%) (p = 0.054). Conclusion: LV reverse remodeling based on LVMi was present even in patients with severely reduced LASr following TAVI, although extensive LA damage based on LA strain was demonstrated by its limited improvement over time. Clinical Trial Registration: (ClinicalTrials.gov number: NCT02826200).

Quantification of hypo-attenuated leaflet thickening after transcatheter aortic valve implantation: clinical relevance of hypo-attenuated leaflet thickening volume.

AIMS: Our aim was to establish an objective, quantitative methodology for volumetric hypo-attenuated leaflet thickening (HALT) diagnosis and evaluate its clinical significance. METHODS AND RESULTS: We prospectively enrolled 144 patients who underwent transcatheter aortic valve implantation (TAVI) between 2011 and 2016. At inclusion, cardiac computed tomography angiography (CTA), transthoracic echocardiography, and brain magnetic resonance imaging (MRI) were performed. We quantified HALT on CTA datasets by segmenting the inner volume of TAVI frame at the level of leaflets and extracted voxels between a threshold of -200 to 200 HU based on prior recommendation. The median HALT volume was 72 [inter-quartile range (IQR): 1-154] mm3 (intra- and inter-reader agreement: intra-class correlation coefficient = 0.92 and 0.94, respectively) and 79% (n = 87/111) of the patients had HALT >0 mm3. In multivariate linear regression, oral anti-coagulation (ß: -0.32; 95% CI: -0.62 to -0.01; P = 0.004) and history of myocardial infarction (ß: 0.32; 95% CI: 0.01-0.63; P = 0.043) were associated with HALT quantity. Log-transformed HALT volume was associated with elevated (>13 mmHg) aortic mean gradient (AMG, OR: 12.85; 95% CI: 1.96-152.93; P = 0.021) and moderate-to-severe valvular degeneration (AMG ≥ 20 mmHg or ΔAMG ≥ 10 mmHg; OR: 10.56; 95% CI: 1.44-148.71; P = 0.046) but did not predict ischaemic brain lesions on MRI or all-cause death after a median follow-up of 29 (IQR: 11-29) months (all P > 0.05). CONCLUSION: Through systematic analysis of asymptomatic patients with TAVI, an objective and reproducible methodology was feasible for volumetric measurement of HALT. Anti-coagulation might have a protective effect against HALT. Ischaemic brain lesions and all-cause death were not associated with HALT; nevertheless, it might deteriorate prosthesis function due to its association with elevated AMG. CLINICAL TRIAL REGISTRATION: http//:www.ClinicalTrials.gov; NCT02826200.

Calcium scoring: a personalized probability assessment predicts the need for additional or alternative testing to coronary CT angiography.

OBJECTIVE: To assess whether anthropometrics, clinical risk factors, and coronary artery calcium score (CACS) can predict the need of further testing after coronary CT angiography (CTA) due to non-diagnostic image quality and/or the presence of significant stenosis. METHODS: Consecutive patients who underwent coronary CTA due to suspected coronary artery disease (CAD) were included in our retrospective analysis. We used multivariate logistic regression and receiver operating characteristics analysis containing anthropometric factors: body mass index, heart rate, and rhythm irregularity (model 1); and parameters used for pre-test likelihood estimation: age, sex, and type of angina (model 2); and also added total calcium score (model 3) to predict downstream testing. RESULTS: We analyzed 4120 (45.7% female, 57.9 ± 12.1 years) patients. Model 3 significantly outperformed models 1 and 2 (area under the curve, 0.84 [95% CI 0.83-0.86] vs. 0.56 [95% CI 0.54-0.58] and 0.72 [95% CI 0.70-0.74], p < 0.001). For patients with sinus rhythm of 50 bpm, in case of non-specific angina, CACS above 435, 756, and 944; in atypical angina CACS above 381, 702, and 890; and in typical angina CACS above 316, 636, and 824 correspond to 50%, 80%, and 90% probability of further testing, respectively. However, higher heart rates and arrhythmias significantly decrease these cutoffs (p < 0.001). CONCLUSION: CACS significantly increases the ability to identify patients in whom deferral from coronary CTA may be advised as CTA does not lead to a final decision regarding CAD management. Our results provide individualized cutoff values for given probabilities of the need of additional testing, which may facilitate personalized decision-making to perform or defer coronary CTA. KEY POINTS: • Anthropometric parameters on their own are insufficient predictors of downstream testing. Adding parameters of the Diamond and Forrester pre-test likelihood test significantly increases the power of prediction. • Total CACS is the most important independent predictor to identify patients in whom coronary CTA may not be recommended as CTA does not lead to a final decision regarding CAD management. • We determined specific CACS cutoff values based on the probability of downstream testing by angina-, arrhythmia-, and heart rate-based groups of patients to help individualize patient management.

Largely Accelerated Arterial Aging in Rheumatoid Arthritis Is Associated With Inflammatory Activity and Smoking in the Early Stage of the Disease.

Background: Rheumatoid arthritis (RA) patients have a shorter life expectancy than the general population primarily due to cardiovascular comorbidities. Objectives: To characterize arterial aging in RA. Patients and Methods: Coronary calcium score (CCS) were available from 112 RA patients; out of these patients, follow-up CCS were measured for 54 randomly selected individuals. Control CCS were obtained from the MESA database (includes 6,000 < participants); arterial age was calculated from CCS. Results: RA patients were significantly older (10.45 ± 18.45 years, p < 0.001) in terms of the arterial age than the age-, gender-, and race-matched controls. The proportion of RA patients who had zero CCS was significantly less (p < 0.01) than that of those in the MESA reference group. Each disease year contributed an extra 0.395 years (p < 0.01) on the top of the normal aging process. However, the rate of the accelerated aging is not uniform, in the first years of the disease it is apparently faster. Smoking (p < 0.05), previous cardiovascular events (p < 0.05), and high blood pressure (p < 0.05) had additional significant effect on the aging process. In the follow-up study, inflammatory disease activity (CRP > 5 mg/L, p < 0.05) especially in smokers and shorter than 10 years of disease duration (p = 0.05) had the largest impact. Conclusion: Arterial aging is faster in RA patients than in control subjects, particularly in the first 10 years of the disease. Inflammation, previous cardiovascular events, and smoking are additional contributing factors to the intensified coronary atherosclerosis progression. These data support that optimal control of inflammation is essential to attenuate the cardiovascular risk in RA.

Subclinical leaflet thrombosis is associated with impaired reverse remodelling after transcatheter aortic valve implantation.

AIMS: Cardiac CT is increasingly applied for planning and follow-up of transcatheter aortic valve implantation (TAVI). However, there are no data available on reverse remodelling after TAVI assessed by CT. Therefore, we aimed to evaluate the predictors and the prognostic value of left ventricular (LV) reverse remodelling following TAVI using CT angiography. METHODS AND RESULTS: We investigated 117 patients with severe, symptomatic aortic stenosis (AS) who underwent CT scanning before and after TAVI procedure with a mean follow-up time of 2.6 years after TAVI. We found a significant reduction in LV mass (LVM) and LVM indexed to body surface area comparing pre- vs. post-TAVI images: 180.5 ± 53.0 vs. 137.1 ± 44.8 g and 99.7 ± 25.4 vs. 75.4 ± 19.9 g/m2, respectively, both P < 0.001. Subclinical leaflet thrombosis (SLT) was detected in 25.6% (30/117) patients. More than 20% reduction in LVM was defined as reverse remodelling and was detected in 62.4% (73/117) of the patients. SLT, change in mean pressure gradient on echocardiography and prior myocardial infarction was independently associated with LV reverse remodelling after adjusting for age, gender, and traditional risk factors (hypertension, body mass index, diabetes mellitus, and hyperlipidaemia): OR = 0.27, P = 0.022 for SLT and OR = 0.22, P = 0.006 for prior myocardial infarction, OR = 1.51, P = 0.004 for 10 mmHg change in mean pressure gradient. Reverse remodelling was independently associated with favourable outcomes (HR = 0.23; P = 0.019). CONCLUSION: TAVI resulted in a significant LVM regression on CT. The presence of SLT showed an inverse association with LV reverse remodelling and thus it may hinder the beneficial LV structural changes. Reverse remodelling was associated with improved long-term prognosis.

Left ventricular and atrial strain imaging with cardiac computed tomography: Validation against echocardiography.

BACKGROUND: Data on left ventricular (LV) deformation imaging using CT angiography (CTA) are scarce and the feasibility of atrial deformation analysis by CT has not been addressed. We aimed to compare 2D echocardiographic and CT derived LV and left atrial (LA) global longitudinal strain (GLS) obtained by using a novel feature tracking algorithm in patients following transcatheter aortic valve implantation. METHODS: Twenty-eight patients were included who underwent retrospectively-gated 256-slice CTA and speckle-tracking echocardiography (STE) on the same day. CT datasets in 10% increments were reconstructed throughout the cardiac cycle. LV GLS and LA global peak reservoir strain (LA GS) was measured. RESULTS: Median absolute values for LV GLS were 19.9 [14.8-22.4] vs. 19.9 [16.8-24.7], as measured by CT vs STE, respectively (p = 0.017). We found good inter-modality correlation for LV GLS (ρ = 0.78, p < 0.05) with a mean bias of -1.6. Regarding atrial measurements, the median LA GS was 19.0 [13.5-27.3] for CT vs. 28.0 [17.5-32.6] for STE (p < 0.001) with a mean bias of -5.6 between CT and STE and a correlation coefficient of ρ = 0.87, p < 0.001. CT measurements were highly reproducible: intra-observer intra-class correlation coefficient was 0.96 for LV GLS and 0.95 for LA GS. CONCLUSION: We detected good correlation between CTA and echocardiography-based LV and LA longitudinal strain parameters. CTA provides accurate strain measurements with high reproducibility. Feature tracking-based deformation analysis could provide a clinically important addition to CT examinations by complementing anatomical information with functional data.

Quantitative CT assessment identifies more heart transplanted patients with progressive coronary wall thickening than standard clinical read.

BACKGROUND: We sought to compare quantitative coronary CT angiography (CTA) assessment versus standard clinical reading to identify heart transplanted (HTX) patients with progressive coronary wall thickening. METHODS: 35 patients (23 males, age 58 [IQR: 50;61] years) underwent 256-slice coronary CTA at one year and two years after HTX to rule out cardiac allograft vasculopathy (CAV). In addition to the standard clinical read, we quantified total vessel wall volume in all coronaries up to 2-mm luminal diameter. Fixed threshold settings were used to assess calcified (>350 HU) and non-calcified vessel wall components with high- (131-350 HU), intermediate- (75-130 HU) and low-attenuation (<75 HU). RESULTS: Total lumen volume did not change between baseline and follow-up studies (p = 0.59). Total vessel wall volume showed significant increase (464 [IQR: 338; 570] vs. 563 [IQR: 345; 717] mm3, p < 0.001). The volume of high-, intermediate and low-attenuation non-calcified wall components showed progression (332 [IQR: 217;425] vs. 385 [IQR: 238;489], 40 [IQR: 12;48] vs. 59 [IQR: 16;83] and 18 [IQR: 4;21] vs. 46 [IQR: 6;41] mm3, respectively, p < 0.05 all), while calcified volume did not change between baseline and follow-up CTAs (72 [IQR: 16;127] vs. 72 [IQR: 29;102] mm3, p = 0.73). Quantitative analysis identified more patients with progressive coronary wall thickening (≥10% cut-off) than standard clinical read (11 vs. 22, p = 0.01). CONCLUSION: Quantitative coronary wall assessment is feasible with coronary CTA in HTX patients. Coronary wall thickening within the first two years after HTX is mainly attributable to non-calcified lesion components and might be an early sign of CAV.

Image Quality of Prospectively ECG-Triggered Coronary CT Angiography in Heart Transplant Recipients.

OBJECTIVE: Cardiac allograft vasculopathy (CAV) is among the top causes of death 1 year after heart transplantation (HTx). Coronary CT angiography (CTA) is a potential alternative to invasive imaging in the diagnosis of CAV. However, the higher heart rate (HR) of HTx recipients prompts the use of retrospective ECG-gating, which is associated with higher radiation dose, a major concern in this patient population. Therefore, we sought to evaluate the feasibility and image quality of low-radiation-dose prospectively ECG-triggered coronary CTA in HTx recipients. MATERIALS AND METHODS: In total, 1270 coronary segments were evaluated in 50 HTx recipients and 50 matched control subjects who did not undergo HTx. The control subjects were selected from our clinical database and were matched for age, sex, body mass index, HR, and coronary dominance. Scans were performed using 256-MDCT with prospective ECG-triggering. The degree of motion artifacts was evaluated on a per-segment basis on a 4-point Likert-type scale. RESULTS: The median HR was 74.0 beats/min (interquartile range [IQR], 67.8-79.3 beats/min) in the HTx group and 73.0 beats/min (IQR, 68.5-80.0 beats/min) in the matched control group (p = 0.58). In the HTx group, more segments had diagnostic image quality compared with the control group (624/662 [94.3%] vs 504/608 [82.9%]; p < 0.001). The mean effective radiation dose was low in both groups (3.7 mSv [IQR, 2.4-4.3 mSv] in the HTx group vs 4.3 mSv [IQR, 2.6-4.3 mSv] in the control group; p = 0.24). CONCLUSION: Prospectively ECG-triggered coronary CTA examinations of HTx recipients yielded diagnostic image quality with low radiation dose. Coronary CTA is a promising noninvasive alternative to routine catheterization during follow-up of HTx recipients to diagnose CAV.

The effect of four-phasic versus three-phasic contrast media injection protocols on extravasation rate in coronary CT angiography: a randomized controlled trial.

OBJECTIVES: Contrast media (CM) extravasation is a well-known complication of CT angiography (CTA). Our prospective randomized control study aimed to assess whether a four-phasic CM administration protocol reduces the risk of extravasation compared to the routinely used three-phasic protocol in coronary CTA. METHODS: Patients referred to coronary CTA due to suspected coronary artery disease were included in the study. All patients received 400 mg/ml iomeprol CM injected with dual-syringe automated injector. Patients were randomized into a three-phasic injection-protocol group, with a CM bolus of 85 ml followed by 40 ml of 75%:25% saline/CM mixture and 30 ml saline chaser bolus; and a four-phasic injection-protocol group, with a saline pacer bolus of 10 ml injected at a lower flow rate before the three-phasic protocol. RESULTS: 2,445 consecutive patients were enrolled (mean age 60.6 ± 12.1 years; females 43.6%). Overall rate of extravasation was 0.9% (23/2,445): 1.4% (17/1,229) in the three-phasic group and 0.5% (6/1,216) in the four-phasic group (p = 0.034). CONCLUSIONS: Four-phasic CM administration protocol is easy to implement in the clinical routine at no extra cost. The extravasation rate is reduced by 65% with the application of the four-phasic protocol compared to the three-phasic protocol in coronary CTA. KEY POINTS: • Four-phasic CM injection-protocol reduces extravasation rate by 65% compared to three-phasic. • The saline pacer bolus substantially reduces the risk of CM extravasation. • The implementation of four-phasic injection-protocol is at no cost.

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.

Cardiac allograft vasculopathy: optical coherence guided innovative treatment options with the bioresorbable vascular scaffold: proof of concept.

The aim of our work was to assess a novel interventional therapy option in cardiac allograft vasculopathy (CAV), a complex form of coronary disease presenting only in heart transplant (HTx) recipients. It is typically a rapidly progressing phenomenon, affecting the entire coronary circulation causing diffuse, severe coronary lesions and has no one unique cause. Treatment options are limited, but where eligible, palliation via percutaneous revascularization (PCI) mainly using new generation drug eluting stents (DES) is recommended. Our working group sought to assess outcomes of CAV PCI using an Absorb (Abbott Vascular, Santa Clara, CA, USA) fully bioresorbable, everolimus eluting vascular scaffold (BVS), under optical coherence tomography (OCT) guidance. Our initial, proof-of-concept case showed a late CAV, macrophage and foam-cell rich lesion, with typical asymmetric intimal hyperplasia and contralateral thin-cap fibroatheroma formation. Post-PCI OCT showed underexpansion, requiring aggressive postdilatation. Ninety-day follow-up CT angiogram identified the scaffold and displayed a patent lumen of the device. BVS use thus seems eligible in CAV, yet needs proper, meticulous implantation. Use may also delay CAV progression as lesion healing is promoted, with restoration of vasomotion and a natural increase in vascular lumen. Furthermore, the chronically present vascular irritation surrounding stent/scaffold struts may subside, as no permanent metal is present as an increased substrate for inflammation. To assess full efficacy, further studies will be needed.

The effect of iterative model reconstruction on coronary artery calcium quantification.

Coronary artery calcium (CAC) scoring with computed tomography (CT) is an established tool for quantifying calcified atherosclerotic plaque burden. Despite the widespread use of novel image reconstruction techniques in CT, the effect of iterative model reconstruction on CAC score remains unclear. We sought to assess the impact of iterative model based reconstruction (IMR) on coronary artery calcium quantification as compared to the standard filtered back projection (FBP) algorithm and hybrid iterative reconstruction (HIR). In addition, we aimed to simulate the impact of iterative reconstruction techniques on calcium scoring based risk stratification of a larger asymptomatic population. We studied 63 individuals who underwent CAC scoring. Images were reconstructed with FBP, HIR and IMR and CAC scores were measured. We estimated the cardiovascular risk reclassification rate of IMR versus HIR and FBP in a larger asymptomatic population (n = 504). The median CAC scores were 147.7 (IQR 9.6-582.9), 107.0 (IQR 5.9-526.6) and 115.1 (IQR 9.3-508.3) for FBP, HIR and IMR, respectively. The HIR and IMR resulted in lower CAC scores as compared to FBP (both p < 0.001), however there was no difference between HIR and IMR (p = 0.855). The CAC score decreased by 7.2 % in HIR and 7.3 % in IMR as compared to FBP, resulting in a risk reclassification rate of 2.4 % for both HIR and IMR. The utilization of IMR for CAC scoring reduces the measured calcium quantity. However, the CAC score based risk stratification demonstrated modest reclassification in IMR and HIR versus FBP.

Esmolol is noninferior to metoprolol in achieving a target heart rate of 65 beats/min in patients referred to coronary CT angiography: a randomized controlled clinical trial.

BACKGROUND: Coronary CT angiography (CTA) is an established tool to rule out coronary artery disease. Performance of coronary CTA is highly dependent on patients' heart rates (HRs). Despite widespread use of ß-blockers for coronary CTA, few studies have compared various agents used to achieve adequate HR control. OBJECTIVE: We sought to assess if the ultrashort-acting ß-blocker intravenous esmolol is at least as efficacious as the standard of care intravenous metoprolol for HR control during coronary CTA. METHODS: Patients referred to coronary CTA with a HR >65 beats/min despite oral metoprolol premedication were enrolled in the study. We studied 412 patients (211 male; mean age, 57 ± 12 years). Two hundred four patients received intravenous esmolol, and 208 received intravenous metoprolol with a stepwise bolus administration protocol. HR and blood pressure were recorded at arrival, before, during, immediately after, and 30 minutes after the coronary CTA scan. RESULTS: Mean HRs of the esmolol and metoprolol groups were similar at arrival (78 ± 13 beats/min vs 77 ± 12 beats/min; P = .65) and before scan (68 ± 7 beats/min vs 69 ± 7 beats/min; P = .60). However, HR during scan was lower in the esmolol group vs the metoprolol group (58 ± 6 beats/min vs 61 ± 7 beats/min; P < .0001), whereas HRs immediately and 30 minutes after the scan were higher in the esmolol group vs the metoprolol group (68 ± 7 beats/min vs 66 ± 7 beats/min; P = .01 and 65 ± 8 beats/min vs 63 ± 8 beats/min; P < .0001; respectively). HR ≤ 65 beats/min was reached in 182 of 204 patients (89%) who received intravenous esmolol vs 162 of 208 of the patients (78%) who received intravenous metoprolol (P < .05). Of note, hypotension (systolic BP <100 mm Hg) was observed right after the scan in 19 patients (9.3%) in the esmolol group and in 8 patients (3.8%) in the metoprolol group (P < .05), whereas only 5 patients (2.5%) had hypotension 30 minutes after the scan in the esmolol group compared to 8 patients (3.8%) in the metoprolol group (P = .418). CONCLUSION: Intravenous esmolol with a stepwise bolus administration protocol is at least as efficacious as the standard of care intravenous metoprolol for HR control in patients who undergo coronary CTA.

Prediction model to estimate presence of coronary artery disease: retrospective pooled analysis of existing cohorts.

OBJECTIVES: To develop prediction models that better estimate the pretest probability of coronary artery disease in low prevalence populations. DESIGN: Retrospective pooled analysis of individual patient data. SETTING: 18 hospitals in Europe and the United States. PARTICIPANTS: Patients with stable chest pain without evidence for previous coronary artery disease, if they were referred for computed tomography (CT) based coronary angiography or catheter based coronary angiography (indicated as low and high prevalence settings, respectively). MAIN OUTCOME MEASURES: Obstructive coronary artery disease (≥ 50% diameter stenosis in at least one vessel found on catheter based coronary angiography). Multiple imputation accounted for missing predictors and outcomes, exploiting strong correlation between the two angiography procedures. Predictive models included a basic model (age, sex, symptoms, and setting), clinical model (basic model factors and diabetes, hypertension, dyslipidaemia, and smoking), and extended model (clinical model factors and use of the CT based coronary calcium score). We assessed discrimination (c statistic), calibration, and continuous net reclassification improvement by cross validation for the four largest low prevalence datasets separately and the smaller remaining low prevalence datasets combined. RESULTS: We included 5677 patients (3283 men, 2394 women), of whom 1634 had obstructive coronary artery disease found on catheter based coronary angiography. All potential predictors were significantly associated with the presence of disease in univariable and multivariable analyses. The clinical model improved the prediction, compared with the basic model (cross validated c statistic improvement from 0.77 to 0.79, net reclassification improvement 35%); the coronary calcium score in the extended model was a major predictor (0.79 to 0.88, 102%). Calibration for low prevalence datasets was satisfactory. CONCLUSIONS: Updated prediction models including age, sex, symptoms, and cardiovascular risk factors allow for accurate estimation of the pretest probability of coronary artery disease in low prevalence populations. Addition of coronary calcium scores to the prediction models improves the estimates.