Long-term prosthetic-associated subclinical thrombotic events evaluation by cardiac CTA after transcatheter aortic valve implantation: incidence and outcomes.

OBJECTIVE: To observe prosthetic-associated subclinical thrombotic events (PASTE) after transcatheter aortic valve implantation (TAVI) by cardiac CTA, and assess their impact on long-term patient outcomes. MATERIALS: We prospectively and consecutively enrolled 188 patients with severe aortic stenosis treated with TAVI from February 2014 to April 2017. At 5 years, 61 of 141 survived patients who had completed annual follow-up CTA (≥ 5 years) were included. We analyzed PASTE by CTA, including hypoattenuated leaflet thickening (HALT), sinus filling defect (SFD), and prosthesis filling defect (PFD). The primary outcome was a major adverse cardiovascular composite outcome (MACCO) of stroke, cardiac re-hospitalization, and bioprosthetic valve dysfunction (BVD); the secondary outcomes were bioprosthetic hemodynamics deterioration (PGmean) and cardiac dysfunction (LVEF). RESULTS: During a median follow-up time of 5.25 years, long-term incidence of HALT, SFD, and PFD were 54.1%, 37.7%, and 73.8%, respectively. In the primary outcome, SFD and early SFD were associated with the MACCO (SFD: p = 0.005; early SFD: p = 0.018), and SFD was a predictor of MACCO (HR: 2.870; 95% CI: 1.010 to 8.154, p = 0.048). In the secondary outcomes, HALT was associated with increased PGmean (p = 0.031), while persistent HALT was correlated with ΔPGmean (ß = 0.38, p = 0.035). SFD was negatively correlated with ΔLVEF (ß = -0.39, p = 0.041), and early SFD was negatively correlated with LVEF and ΔLVEF (LVEF: r = -0.50, p = 0.041; ΔLVEF: r = -0.53, p = 0.030). CONCLUSIONS: PASTE were associated with adverse long-term outcomes, bioprosthetic hemodynamics deterioration, and cardiac dysfunction. In particular, SFD was a predictor of MACCO and may be a potential target for anticoagulation after TAVI (NCT02803294). REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; Unique identifier: NCT02803294. CRITICAL RELEVANCE STATEMENT: PASTE, especially SFD, after TAVI based on cardiac CTA findings impacts the long-term outcomes of patients which is a predictor of long-term major adverse outcomes in patients and may be a potential target for anticoagulation after TAVI. KEY POINTS: Transcatheter aortic valve implantation is being used more often; associated subclinical thromboses have not been thoroughly evaluated. Prosthetic-associated subclinical thrombotic events were associated with adverse outcomes, bioprosthetic hemodynamics deterioration, and cardiac dysfunction. Studies should be directed at these topics to determine if they should be intervened upon.

Agreement of ejection fraction measured by coronary computed tomography (CT) and cardiac ultrasound in evaluating patients with chronic heart failure: an observational comparative study.

Background: Cardiac ultrasound is one of the most important examinations in cardiovascular medicine, but the technical requirements for the operator are relatively high, which to some extent affects the scope of its use. This study was dedicated to investigating the agreement of ejection fraction between coronary computed tomography (CT) and cardiac ultrasound and diagnostic performance in evaluating the clinical diagnosis of patients with chronic heart failure. Methods: We conducted a single-center-based retrospective study including 343 consecutive patients enrolled between January 2019 to April 2020, all of whom presented with suspected symptoms of heart failure within one month. All enrolled cases performed cardiac ultrasound and coronary CT scans. The CT images were analyzed using accurate left ventricle (AccuLV) artificial intelligence (AI) software to calculate the ejection fraction-computed tomography (EF-CT) and it was compared with the ejection fraction (EF) obtained based on ultrasound. Cardiac insufficiency was determined if the EF measured by ultrasound was below 50%. Diagnostic performance analysis, correlation analysis and Bland-Altman plot were used to compare agreement between EF-CT and CT. Results: Of the 319 successfully performed patients, 220 (69%) were identified as cardiac insufficiency. Quantitative consistency analysis showed a good correlation between EF-CT and EF values in all cases (R square =0.704, r=0.837). Bland-Altman analysis showed mean bias of 6.6%, mean percentage error of 27.5% and 95% limit of agreement of -17% to 30% between EF and EF-CT. The results of the qualitative diagnostic study showed that the sensitivity and specificity of EF measured by coronary CT reached a high level of 91% [95% confidence interval (CI): 86-94%], and the positive diagnostic value was up to 96% (95% CI: 92-98%). Conclusions: The EF-CT and EF have excellent agreement, and AccuLV-based AI left ventricular function analysis software perhaps can be used as a clinical diagnostic reference.

A new method using surface landmarks to locate resuscitative endovascular balloon occlusion of the aorta based on a retrospective CTA study.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) can timely prevent the wounded from fatal hemorrhage. However, blind insertion of REBOA in field or emergency room may result in catheter malposition and serious complications. We aim to develop a new method based on surface landmarks to guide the accurate placement of REBOA in zone III of aorta without fluoroscopy. METHODS: A retrospective study was conducted in a university hospital, including 57 subjects who underwent computed tomography angiography (CTA) from April to December in 2019. External distances and intravascular lengths were measured by three-dimensional reconstruction of CT images, including the distances from the insertion site of femoral artery to the xiphoid process (FA-Xi), the midpoint between the xiphoid process and the umbilicus (FA-mXU), the umbilicus (FA-Ui), the midpoint of the zone III of aorta (FA-mZIII), the lowest renal artery (FA-LRA), and aortic bifurcation (FA-AB). The distal and proximal ideal margin and predicted accuracy were calculated by curvature plane reconstruction. The predicted probability of balloon positioning in zone III by different methods was compared. RESULTS: The mean age of all patients was 60 years (SD = 9.4). The average length of zone III of aorta was 9.4 cm (SD = 1.0), and the length of FA-mZIII on the right and left sides were 24.4 cm (SD = 2.1), 23.8 cm (SD = 2.1), respectively. FA-Xi was longer than FA-LRA, and FA-Ui was shorter than FA-AB (paired two-tailed test, p < 0.001). Using three methods including the optimal quartering distances, the optimal distances below the xiphoid and above the umbilicus to predict the length of REBOA catheter positioning in zone III showed no statistically significant difference. The predicted accuracy of catheter positioning in zone III on the left and right sides guided by FA-mXU were 84.2% and 86%. CONCLUSIONS: The midpoint between the xiphoid process and the umbilicus may be a new surface landmark for people of normal weight to guide rapid positioning REBOA in zone III of aorta without fluoroscopy.

Relationship between urate within tophus and bone erosion according to the anatomic location of urate deposition in gout: A quantitative analysis using dual-energy CT volume measurements.

The aim of this study was to measure the urate volume within tophus and bone erosion volume using dual-energy computed tomography in patients with tophaceous gout. Furthermore, our study aims to quantitatively analyze the relationship between monosodium urate (MSU) crystal deposition and bone erosion according to the anatomic location of urate deposition.Seventy-seven subjects with chronic gout were positively identified for the presence of urate deposition. Only 27 subjects identified for the presence of urate in contact with bone erosion were included in this study. The urate volumes and associated erosion volumes were measured. The relationships between urate within tophus and bone erosion were separately analyzed according to the anatomic location of urate deposition.Twenty-seven subjects were all male (100%) with a median (interquartile range, IQR) age of 52 (45-61) years. From all the subjects, 103 tophi depositions were identified in contact with bone erosion, including 58/103 tophi that contained an intraosseous component and 45/103 nonintraosseous tophi. Tophi containing intraosseous components were larger than nonintraosseous tophi (urate volume: median [IQR] 45.64 [4.79-250.89] mm vs 19.32 [6.97-46.71] mm, P = .035) and caused greater bone erosion (erosion volume: 249.03 [147.08-845.33] mm vs 69.07 [32.88-111.24] mm, P < .001). Almost all erosion volumes were larger than urate volumes in nonperiarticular tophi, in contrast to most erosion volumes, which were less than urate volumes in the tophi that contained a periarticular component (odds ratio, 95% confidence interval: 74.00, 14.70-372.60; P < .001). Urate volume and erosion volume demonstrated positive correlations in intraosseous tophi, intraosseous-intra-articular-periarticular tophi, and intraosseous-intra-articular tophi (rs = 0.761, rs = 0.695, rs = 0.629, respectively, P < .05).MSU crystal deposition shows a promoting effect on the development of bone erosions in varying degrees, associated with the location of MSU crystals deposited in the joints. The intraosseous tophi contribute the most to bone erosions, followed by intra-articular tophi, and periarticular tophi.

Ascending aortic dilatation rate after transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis: A multidetector computed tomography follow-up study.

BACKGROUND: Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement (TAVR) in aortic stenosis (AS) patients with bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV). This study aims to assess the ascending aortic dilatation rate (mm/year) after TAVR in patients with BAV versus TAV using a multidetector computed tomography (MDCT) follow-up and to determine the predictors of ascending aortic dilatation rate. METHODS: Severe AS patients undergoing TAVR from March 2013 to March 2018 at our center with MDCT follow-ups were included. BAV and TAV were identified using baseline MDCT. Baseline and follow-up MDCT images were analyzed, and the diameters of ascending aorta were measured. Study end point is ascending aortic dilatation rate (mm/year). Furthermore, factors predicting ascending aortic dilatation rate were also investigated. RESULTS: Two hundred and eight patients were included, comprised of 86 BAV and 122 TAV patients. Five, 4, 3, 2, and 1-year MDCT follow-ups were achieved in 7, 9, 30, 46, and 116 patients. The ascending aortic diameter was significantly increased after TAVR in both BAV group (43.7±4.4 mm vs. 44.0±4.5 mm; P<0.001) and TAV group (39.1±4.8 mm vs. 39.7±5.1 mm; P<0.001). However, no difference of ascending aortic dilatation rate was found between BAV and TAV group (0.2±0.8 mm/year vs. 0.3±0.8 mm/year, P=0.592). Multivariate linear regression revealed paravalvular leakage (PVL) grade was independently associated with ascending aortic dilatation rate in the whole population and BAV group, but not TAV group. No aortic events occurred during follow-ups. CONCLUSION: Ascending aortic size continues to grow after TAVR in BAV patients, but the dilatation rate is mild and comparable to that of TAV patients. PVL grade is associated with ascending aortic dilatation rate in BAV patients post-TAVR.

Supra-annular structure assessment for self-expanding transcatheter heart valve size selection in patients with bicuspid aortic valve.

OBJECTIVES: To explore assessment of supra-annular structure for self-expanding transcatheter heart valve (THV) size selection in patients with bicuspid aortic stenosis (AS). BACKGROUND: Annulus-based device selection from CT measurement is the standard sizing strategy for tricuspid aortic valve before transcatheter aortic valve replacement (TAVR). Because of supra-annular deformity, device selection for bicuspid AS has not been systemically studied. METHODS: Twelve patients with bicuspid AS who underwent TAVR with self-expanding THVs were included in this study. To assess supra-annular structure, sequential balloon aortic valvuloplasty was performed in every 2 mm increments until waist sign occurred with less than mild regurgitation. Procedural results and 30 day follow-up outcomes were analyzed. RESULTS: Seven patients (58.3%) with 18 mm; three patients (25%) with sequential 18 mm, 20 mm; and only two patients (16.7%) with sequential 18 mm, 20 mm, and 22 mm balloon sizing were performed, respectively. According to the results of supra-annular assessment, a smaller device size (91.7%) was selected in all but one patient compared with annulus based sizing strategy, and the outcomes were satisfactory with 100% procedural success. No mortality and 1 minor stroke were observed at 30 d follow-up. The percentage of NYHA III/IV decreased from 83.3% (9/12) to 16.7% (2/12). No new permanent pacemaker implantation and no moderate or severe paravalvular leakage were found. CONCLUSIONS: A supra-annular structure based sizing strategy is feasible for TAVR in patients with bicuspid AS.

First-in-man implantation of the retrievable and repositionable VenusA-Plus valve.

BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. METHODS: A 76-year-old patient with symptomatic severe aortic stenosis and high surgical risk (STS 13.8%) was recommended for transcatheter aortic valve replacement (TAVR) by heart valve team. Type 0 bicuspid aortic valve with asymmetric calcification was identified by dual source computed tomography, and the unfavorable anatomies increased the possibility of malposition and paravalvular leakage during TAVR. Therefore, we used the retrievable and repositionable VenusA-Plus valve for the patient. RESULTS: Transfemoral TAVR was performed under local anesthesia with sedation, and a 26mm VenusA-Plus valve was successfully implanted. No transvalvular pressure gradient and trace paravalvular leakage were found. CONCLUSION: The successful first-in-man implantation indicates the retrievable and repositionable VenusA-Plus valve is feasible in complicated TAVR cases such as bicuspid aortic valve.

Combining Hyperechoic Aggregates and the Double-Contour Sign Increases the Sensitivity of Sonography for Detection of Monosodium Urate Deposits in Gout.

OBJECTIVES: To compare the sensitivities of individual and combined sonography of hyperechoic aggregates and the double-contour sign in detecting monosodium urate (MSU) crystal deposits in gouty joints. METHODS: Monosodium urate crystal deposits in symptomatic and contralateral asymptomatic joints of 70 patients with acute gout were evaluated by sonography of hyperechoic aggregates and the double-contour sign individually and in combination. All patients with acute gout in this study had at least 1 symptomatic joint with MSU deposits determined by dual-energy computed tomography. RESULTS: Of 195 symptomatic joints (92 in the upper limbs and 103 in the lower limbs) and an equal number of asymptomatic joints: (1) 97.14% (68 of 70) of patients had hyperechoic aggregate/double-contour sign-positive joints versus 74.29% (52 of 70) with double-contour sign-positive and 63.89% (46 of 70) with hyperechoic aggregate-positive joints; (2) 86.96% (80 of 92) of the symptomatic upper limb joints were double-contour sign/hyperechoic aggregate positive versus 46.74% (43 of 92) that were double-contour sign positive and 70.65% (65 of 92) that were hyperechoic aggregate positive; and (3) 98.06% (101 of 103) of the symptomatic lower limb joints were double-contour sign/hyperechoic aggregate positive versus 92.23% (95 of 103) that were double-contour sign positive and 41.75% (43 of 103) that were hyperechoic aggregate positive. CONCLUSIONS: Hyperechoic aggregates and the double-contour sign in combination improve the investigative sensitivity of sonography than either hyperechoic aggregates or the double-contour sign individually for detecting MSU crystal deposits in gouty joints.

[Diagnostic value of dual energy CT for lymph node metastasis in patients with non-small cell lung cancer].

OBJECTIVE: To assess the diagnostic value of dual energy CT for lymph node metastasis in patients with non-small cell lung cancer (NSCLC). METHODS: Forty NSCLC patients, including 15 cases of squamous cell carcinoma and 25 cases of adenocarcinoma, underwent dual energy CT examination in pre-contrast and venous phase contrast scans, then the CT attenuation value of the lung cancer lesions and 85 mediastinal enlarged lymph nodes (the short diameter ≥ 5 mm, 53 metastatic and 32 non-metastatic) were measured at different energy levels (40-190 keV, spacing 10 keV) in venous phase contrast. CT spectral curves of the lung cancer lesions, hilus pulmonis and mediastinal enlarged lymph nodes were produced automatically, through comparing their CT spectral curves slope to judge whether or not the lymph nodes were metastatic. Receiver operating characteristic (ROC) curve was used to evaluate the efficiency of CT spectral curve in diagnosis of lymph node metastasis. RESULTS: The CT spectral curves slopes of the lung cancer, metastatic lymph nodes and non-metastatic lymph nodes were 1.10±0.11, 1.08±0.07 and 1.54±0.17, respectively. There was no significant difference in curve slope between metastatic lymph nodes and lung cancer (t=-1.32,P>0.05); while there was significant difference between non-metastatic lymph nodes and lung cancer (t=-2.58,P<0.05). The CT spectral curve slope ratios of metastatic and non-metastatic lymph nodes to lung cancer were 0.98±0.05 and 1.40±0.12, respectively (t=-2.86,P<0.05). ROC curve showed that taking CT spectral curve slope ratio of 1.15 as cut-off value for the diagnosis of metastatic lymph nodes, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 81.1%, 87.5%, 91.5%, 73.7% and 83.5%, respectively. CONCLUSIONS: Dual energy CT is of value in improving the diagnostic accuracy of lymph node metastasis in NSCLC patients before treatment.

Evaluation of the safety and efficacy of transcatheter aortic valve implantation in patients with a severe stenotic bicuspid aortic valve in a Chinese population.

OBJECTIVE: The purpose of this study is to evaluate the safety and efficacy of transcatheter aortic valve implantation (TAVI) in patients with a severe stenotic bicuspid aortic valve (BAV) in a Chinese population. While several groups have reported the feasibility, efficacy, and safety of TAVI for patients with a BAV, worldwide experience of the technique is still limited, especially in China. METHODS: From March 2013 to November 2014, high surgical risk or inoperable patients with symptomatic severe aortic stenosis (AS) who had undergone TAVI at our institution were selected for inclusion in our study. RESULTS were compared between a BAV group and a tricuspid aortic valve (TAV) group. RESULTS: Forty patients were included in this study, 15 (37.5%) of whom were identified as having a BAV. In the BAV group, the aortic valve area was smaller ((0.47±0.13) vs. (0.59±0.14) cm(2)), the ascending aortic diameter was larger ((40.4±4.4) vs. (36.4±4.3) mm), and the concomitant aortic regurgitation was lower. No significant differences were found between the groups in the other baseline characteristics. No differences were observed either in the choice of access or valve size. The procedural success achieved in this study was 100%. There were no differences between groups in device success (86.7% vs. 88.0%), 30-d mortality (6.7% vs. 8.0%), or 30-d combined end point (13.3% vs. 12.0%). The incidences of new pacemaker implantation, paravalvular regurgitation and other complications, recovery of left ventricle ejection fraction and heart function were similar in both groups. CONCLUSIONS: Patients with a severely stenotic BAV can be treated with TAVI, and their condition after treatment should be similar to that of people with a TAV.

Methods of assessment of tophus and bone erosions in gout using dual-energy CT: reproducibility analysis.

This study aims to evaluate the intraobserver and interobserver reproducibility of the tophus urate volume, erosion volume, and the erosion score measurements in patients with gout by using dual-energy CT (DECT) scans comparing their bone erosion volumes against bone erosion scores and also to determine a valid measure of joint destruction in chronic gout. Sixty-six subjects underwent DECT scans of the hands or feet. Two independent observers measured the tophus urate volumes and bone erosion volumes using automated volume assessment software and the erosion scores based on the rheumatoid arthritis magnetic resonance imaging score (RAMRIS). The intraobserver and interobserver reproducibility were analyzed by intraclass correlation coefficient (ICC) and limits of agreements analysis. The relationship between erosion volumes and erosion scores was analyzed. The intraobserver and interobserver ICC for tophus urate volume measurements (n = 636) were 1.000 (95 % confidence interval (95 % CI) 1.000 to 1.000) and 1.000 (95 % CI 1.000 to 1.000), 0.999 (0.999, 0.999) and 0.999 (0.999, 0.999) for bone erosion volumes (n = 350), 0.937 (0.928, 0.946) and 0.899 (0.883, 0.912) for erosion scores (n = 350). Strong positive correlations were demonstrated between individual erosion volumes and scores (r s = 0.914, p < 0.001) as well as total erosion volume and score per patient (r = 0.838-0.867, p < 0.001). This study demonstrated a high reproducibility of tophus urate volumes, erosion volumes, and erosion score measurements using DECT. Erosion volumes show to be a more direct and accurate method to evaluate bone erosion compared with erosion score, strongly supporting it as a superior and standard measure of structural joint damage in gout.

[Value of preoperative assessment on transcatheter aortic valve implantation procedure with high-pitch dual-source computed tomography angiography].

OBJECTIVE: To evaluate the value of preoperative assessment on transcatheter aortic valve implantation (TAVI) procedure with high-pitch dual-source computed tomography angiography (CTA). METHODS: Seventeen consecutive patients with severe symptomatic aortic stenosis underwent TAVI in our department from December 2012 to December 2013 were examined by 128-slice prospective ECG-triggered high-pitch spiral CTA and the clinical data were analyzed. Aortic annulus, sinus of Valsalva, sinotubular junction, ascending aorta and native leaflet to coronary ostium length were measured. Peripheral vascular access was evaluated. Then the patients were assessed on the suitability for TAVI procedure and prosthetic valve sizes. RESULTS: Mean diameter of the aortic annulus was (25.7 ± 2.0) mm, perimeter mean diameter was (26.4 ± 2.0) mm, area mean diameter was (25.4 ± 1.9) mm. Mean diameter of sinus of Valsalva was (34.0 ± 3.8) mm. Mean diameter of sinotubular junction was (30.5 ± 3.2) mm. Mean diameter of ascending aorta was (37.8 ± 2.8) mm. The length from native leaflet to left coronary ostium was (14.0 ± 2.0) mm, and the length from native leaflet to right coronary ostium was (15.9 ± 3.6) mm. Mean diameter of left iliac arteries was (7.5 ± 1.4) mm. Mean diameter of right iliac arteries was (7.4 ± 1.2) mm. Mean diameter of left femoral arteries was (7.4 ± 1.2) mm. Mean diameter of right femoral arteries was (7.3 ± 1.3) mm. One patient was considered ineligible for TAVI because of large aortic annulus diameter. Three patients died prior to TAVI. Two patients refused to undergo TAVI. Eleven patients underwent TAVI, 26# prosthetic valve was implanted in 1 patient, 29# prosthetic valve implanted in 6 patients, 31# prosthetic valve implanted in 4 patients. Prosthetic valve implantation was successful in 9 patients and only mild or trace perivalvular leakage was observed in these patients. Moderate perivalvular leakage were observed in 2 patients because of the location of implantation was too low, and perivalvular leakage was significantly reduced after re-implantation with same size prosthetic valve at a higher location. CONCLUSIONS: CTA can be used to evaluate the aortic root anatomy and vascular access, and help to choose the right size of prosthetic valve. CTA has an important practical value in preoperative screening of TAVI procedure.

The application of dual-energy computed tomography in the diagnosis of acute gouty arthritis.

The aim of the study was to investigate the sensitivity and specificity of dual-energy computed tomography in the diagnosis of acute gouty arthritis, and the related risk factors for urate crystal deposition. One hundred ninety-one patients (143 with acute gouty arthritis and 48 with other arthritic conditions) were studied. All patients had acute arthritic attack in the recent 15 days and underwent dual-energy computed tomography (DECT) scan with the affected joints. The urate volume was calculated by DECT and the basic information of these patients was recorded at the same time. Uric acid crystals were identified with DECT in 140 of 143 (97.9 %) gout patients and 6 of 48 (12.5 %) of nongout patients, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of DECT in the diagnosis of acute gouty arthritis were 97.9, 87.5, 95.9, and 93.3 %, respectively. The urate volumes were ranged from 0.57 to 54,543.27 mm(3) with a mean volume of 1,787.81 ± 7,181.54 mm(3). Interestingly, urate volume was correlated with the disease duration, serum uric acid levels, the presence of tophi, and bone erosion. Two-year follow-up data was available in one patient with recurrent gouty arthritis, whose urate volume was gradually reduced in size by DECT detection after urate-lowering therapies. DECT showed high sensitivity and specificity for the identification of urate crystals and diagnosis of acute gout. The risk factors for uric acid deposition include the disease duration, serum uric acid levels, the presence of tophi, and bone erosion. DECT has an important role in the differential diagnosis of arthritis, and also could be served as a follow-up tool.

Computed tomography coronary stent imaging with iterative reconstruction: a trade-off study between medium kernel and sharp kernel.

OBJECTIVE: To evaluate the improvement of iterative reconstruction in image space (IRIS) technique in computed tomographic (CT) coronary stent imaging with sharp kernel, and to make a trade-off analysis. MATERIALS AND METHODS: Fifty-six patients with 105 stents were examined by 128-slice dual-source CT coronary angiography (CTCA). Images were reconstructed using standard filtered back projection (FBP) and IRIS with both medium kernel and sharp kernel applied. Image noise and the stent diameter were investigated. Image noise was measured both in background vessel and in-stent lumen as objective image evaluation. Image noise score and stent score were performed as subjective image evaluation. RESULTS: The CTCA images reconstructed with IRIS were associated with significant noise reduction compared to that of CTCA images reconstructed using FBP technique in both of background vessel and in-stent lumen (the background noise decreased by approximately 25.4% ± 8.2% in medium kernel (P