Malnutrition leads to the progression of coronary artery calcification in hemodialysis patients.

BACKGROUND: Malnutrition is considered a risk factor for cardiovascular disease in patients with chronic kidney disease. However, no in vivo studies have reported on using optical coherence tomography to evaluate the effect of nutritional status on coronary atherosclerosis in hemodialysis patients. We aimed to conduct a detailed analysis of the effect of nutritional status on the coronary arteries in hemodialysis patients. METHODS: Among 64 hemodialysis patients who underwent percutaneous coronary interventions, 41 that underwent optical coherence tomography imaging were included in this study. And, among them, 24 patients that could also be evaluated using OCT also at the 6-month follow-up were included in this study. The patients were divided into two groups based on nutritional evaluation using the geriatric nutritional risk index. Culprit and non-culprit lesions were evaluated at baseline and after 6 months. RESULTS: In the culprit lesions at baseline, the length of the lipid plaque was significantly smaller in the malnutrition group. In contrast, the thickness and length of the calcified plaque and the angle of the calcified nodule were significantly larger (each p < 0.01). In the non-culprit lesions, the 6-month change in the angle of the calcified plaque was significantly greater in the malnutrition group (p = 0.02). The significant factors that affected the change in the angle of calcification were "malnutrition at geriatric nutritional risk index" [odds ratio, 8.17; 95% confidence interval, 1.79 to 37.33; p < 0.01] and "serum phosphorus level" (odds ratio, 3.73; 95% confidence interval, 1.42 to 9.81; p < 0.01). CONCLUSIONS: Appropriate management of nutritional status is crucial for suppressing the progression of coronary artery disease in hemodialysis patients.

Impact of High-Sensitivity Cardiac Troponin Elevation in Relation to Diagnostic Invasive Intravascular Imaging for the Assessment of Coronary Artery Disease.

Recent studies reported that cardiac troponin elevation after percutaneous coronary intervention is related to adverse cardiac events. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are often used to assess lesion characteristics in the coronary arteries. However, little is known about the trend of cardiac troponin elevation after diagnostic invasive intracoronary examination and the prognostic influence. We assessed the relationship between myocardial injury manifested by the high-sensitivity cardiac troponin T (hs-cTnT) level after invasive intracoronary examination and future adverse cardiac outcomes. We evaluated 115 patients with stable coronary artery disease who underwent IVUS or OCT for detailed coronary assessment during coronary angiography (CAG). Baseline and post-procedural (within 24 hours after examination) hs-cTnT were measured. In consequence, post-procedural hs-cTnT level and percentage increase were higher in patients with IVUS or OCT during CAG than in those without. Periprocedural myocardial injury (PMI, defined as post-procedural hs-cTnT with upper reference limit greater than five-fold) occurred in 10 (8.6%) patients. There were no significant differences in baseline characteristics between patients with and without PMI, except for left-ventricular diastolic dimension. Only two major adverse cardiac events (MACE, defined as cardiovascular death, nonfatal myocardial infarction, and target lesion revascularization) occurred in non-PMI during a mean observation period of 32 ± 18 months. On Kaplan-Meier analysis, MACE-free survival rate was similar between PMI and non-PMI. In conclusion, a few imperceptible PMI derived by hs-cTnT assay occurred after diagnostic invasive intracoronary examination. However, it was not associated with subsequent poor cardiac outcome.

Comparison between minimum lumen cross-sectional area and intraluminal ultrasonic intensity analysis using integrated backscatter intravascular ultrasound for prediction of functionally significant coronary artery stenosis.

Intravascular ultrasound (IVUS)-derived minimum lumen cross-sectional area (MLA) is useful to predict myocardial ischemia using fractional flow reserve (FFR). Recent studies reported an increase in the intraluminal ultrasonic integrated backscatter (IB) value using IVUS across the coronary artery stenosis (CAS) was significantly correlated with FFR. However, these details have not been fully understood. We evaluated the utility of intraluminal IB analysis for predicting myocardial ischemia based on FFR measurements by comparing that with conventional IVUS-derived MLA. A total of 65 patients with 75 intermediate lesions underwent both FFR and IB-IVUS simultaneously were analyzed. We measured IVUS-derived MLA and intraluminal IB value at the coronary ostial site, 5 mm distal site to the CAS, and far distal site, which is the same as the position of the pressure wire sensor. The increase in IB values was calculated as the distal IB value - the ostial IB value (focal ∆IB) and the far distal IB value - the ostial IB value (total ∆IB). MLA did not show a significant correlation with FFR (p = 0.13); however, focal ∆IB and total ∆IB showed significant correlations with FFR (p = 0.008 and p < 0.001, respectively). The receiver operating characteristic curve analysis shows that the best cut-off value of focal ∆IB and total ∆IB was 8 and 14, respectively. Although the diagnostic abilities to predict FFR ≤ 0.75 among IVUS-derived MLA ≤ 3.0 mm2, focal ∆IB ≥ 8, and total ∆IB ≥ 14 were similar, a multivariate analysis showed that total ∆IB was the most useful index (p < 0.001). In conclusion, total ∆IB, which is measured at the same as the position of FFR measurement, might be useful for functional assessment of intermediate CAS.

Bleeding and ischemic events during dual antiplatelet therapy after second-generation drug-eluting stent implantation in hemodialysis patients.

BACKGROUND: Dual-antiplatelet therapy (DAPT) after second-generation drug-eluting stent (2nd-DES) implantation reduces the risk of stent thrombosis and subsequent ischemic events, with an increase in bleeding risk. Although chronic kidney disease patients have both high ischemic and bleeding events, little is known about both risks during DAPT in hemodialysis (HD) patients. METHODS: From July 2009 to March 2017, we retrospectively analyzed bleeding events and major adverse cardiac and cerebrovascular events (MACCE) in 644 consecutive patients who underwent successful percutaneous coronary intervention (PCI) with 2nd-DES implantation in our institution. We divided the patients into 2 groups [102 HD and 518 non-HD patients] after excluding 24 patients. The primary endpoint was bleeding events of Bleeding Academic Research Consortium (BARC) type 2, 3, or 5. The secondary endpoint was MACCE. We also investigated potential bleeding risk factors in those patients. RESULTS: At a median follow-up of 49 months, bleeding events occurred in 76 (12.3%) patients. Critical bleeding events of BARC type 3 or 5 occurred more frequently in HD (HD vs. non-HD: 16.7% vs. 7.1%; p=0.004). Most events tended to occur within 6 months post PCI. Multivariate analysis demonstrated that HD [hazard ratio (HR) 2.50, 95% confidence interval (CI) 1.03-3.16; p=0.04], body mass index (BMI) (HR 0.91, 95%CI 0.87-0.99, p=0.02), and serum albumin (HR 0.35, 95%CI 0.34-0.96, p=0.03) were independent predictors of bleeding events. MACCE also occurred more frequently in HD (HD vs. non-HD: 53.9% vs. 29.3%; p<0.001). Multivariate analysis demonstrated that pre-dialysis systolic blood pressure (HR 1.03, 95%CI 1.00-1.06, p=0.02) and high-sensitive C-reactive protein level (HR 1.76, 95%CI 1.06-2.72, p=0.03) were independent predictors of bleeding events in HD. CONCLUSIONS: HD displayed more adverse bleeding and ischemic events compared with non-HD. Therefore, practitioners should reconsider the current regimen of DAPT in this patient cohort to prevent critical bleeding complications and spates of ischemic events.

Contribution of Poststent Irregular Protrusion to Subsequent In-Stent Neoatherosclerosis after the Second-Generation Drug-Eluting Stent Implantation.

Previous optical coherence tomography (OCT) study reported that irregular protrusion (IP) post drug-eluting stent (DES) implantation was an independent predictor of clinical outcome; however, the relationship between IP and the presence of subsequent in-stent neoatherosclerosis remains unclear. This study aimed to assess the relationship between IP and in-stent neoatheroscrerosis formation using OCT. We evaluated 83 patients (101 lesions) who underwent second-generation DES implantation and 8-month follow-up (8M-FU) using OCT. Lesions were divided into two groups in presence of IP (IP: n = 43, non-IP: n = 58). At prepercutaneous coronary intervention (pre-PCI), lipid-rich plaque, lesions with positive remodeling, and in-stent thrombus formation were more frequent in IP than in non-IP. On multivariate analysis, the thrombus at pre-PCI and the lesions with positive remodeling were independent predictors of IP. At 8M-FU, heterogeneous neointima, microvessel, lipid-laden neointima, and thin-cap fibro-atheroma like neointima were more frequent in IP than in non-IP (respectively, P < 0.05). On multivariate analysis, IP was associated with heterogeneous neointima. Binary restenosis was more frequent and late lumen loss tended to be larger in IP than in non-IP (19% versus 5%, P = 0.04; 1.25 ± 1.24 mm versus 0.91 ± 0.63 mm, P = 0.09); however, the target lesion revascularization rate was similar in both groups at 8M-FU. In conclusion, our study suggested that poststent IP was associated with subsequent neoatherosclerosis formation at 8M-FU after the second-generation DES implantation.

Impact of lesion complexity on long-term vascular response to cobalt-chromium everolimus-eluting stent: five-year follow-up optical coherence tomography study.

The impact of lesion complexity on long-term vascular response to cobalt-chromium everolimus-eluting stent (CoCrEES) remains unclear. We sought to evaluate them using optical coherence tomography (OCT). A total of 47 patients with 58 lesions treated only with CoCrEES and no target-vessel events within 5 years after implantation were prospectively enrolled and underwent 5-year follow-up OCT. Quantitative parameters and qualitative characteristics of the neointima were evaluated using multilevel logistic or linear regression models with random effects at three levels: lesion, cross-section (CS), and strut. According to the lesion complexity, the lesions were classified into the two groups: the complex lesion (CL) and non-CL group. The CL was defined as having at least 1 high-risk feature such as acute coronary syndrome lesion, lesion length > 20 mm, severe calcification requiring rotational atherectomy, and chronic total occlusion at the index procedure. A total of 11,034 struts (CL, n = 6240; non-CL, n = 4794) and 1202 (CL, n = 683; non-CL, n = 519) CSs were analyzed. The percentage of uncovered and malapposed struts did not differ significantly between the CL and non-CL groups (0.90 vs. 0.54%, P = 0.78; 0.56 vs. 0.10%, P = 0.16, respectively). The incidence of neoatherosclerosis was comparable between both groups in the CS- and lesion-level analysis (3.5 vs. 4.6%, P = 0.91; 32.0 vs. 24.2%, P = 0.52, respectively). At 5 years, CoCrEES shows an excellent vascular healing and similar frequency of neoatheroslerosis in patients without target-vessel events, regardless of the lesion complexity.

Impact of additional intracoronary nicorandil administration during fractional flow reserve measurement with intravenous adenosine 5'-triphosphate infusion.

BACKGROUND: Fractional flow reserve (FFR) is a useful index for determining the functional severity of epicardial coronary artery stenosis as an invasive physiological method. Although intravenous adenosine 5'-triphosphate (ATP) is generally used as a hyperemic agent for FFR measurement in Japan, there are some concerns about the variability of FFR measurement (short half-life, effect of caffeine, cyclic change). It is difficult to confirm sufficient maximum hyperemia after ATP infusion. Recent studies reported that nicorandil (NIC) could be an alternative to ATP as a hyperemic agent. METHODS: Patients who underwent FFR assessments of angiographically intermediate lesions were included. All patients were asked to refrain from caffeine-containing products more than 12hours before FFR measurements. All patients first received intravenous (IV) ATP infusion (180µg/kg/min) for 3min to measure FFR (ATP-FFR). After additional intracoronary (IC) NIC administration (2mg/30s) during ATP infusion, FFR was measured again (NIC-FFR). To check cyclic change in FFR, we measured minimum and maximum FFR values during both ATP and NIC hyperemic phase. RESULTS: In this study, 94 patients with 94 lesions were enrolled. Mean FFR value was 0.81±0.10 in ATP-FFR infusion and 0.80±0.09 in NIC-FFR, respectively. ATP-FFR and NIC-FFR had a strong correlation on the whole (r=0.92, p<0.001). In 18 patients (19%), FFR values were significantly lower in NIC-FFR than in ATP-FFR. In one-third of those patients (6%), it was possible to change therapeutic strategy from deferral range (>0.80) to interventional range (≦0.80) after NIC-FFR measurements. Cyclic change in FFR was smaller in NIC-FFR than in ATP-FFR (0.03±0.02 vs. 0.06±0.05, p<0.0001). CONCLUSION: Additional IC NIC might be useful to confirm sufficient maximum hyperemia after IV ATP infusion in daily clinical practice. Furthermore, IC NIC could reduce cyclic change in FFR; thus, physicians might find it easier to determine FFR value during the procedure.

Coronary plaque progression of non-culprit lesions after culprit percutaneous coronary intervention in patients with moderate to advanced chronic kidney disease: intravascular ultrasound and integrated backscatter intravascular ultrasound study.

Previous studies have suggested that the deterioration of renal function increases the risk of major adverse clinical events not only in culprit lesions but also in non-culprit lesions (NCLs) after percutaneous coronary intervention (PCI). This study evaluated serial coronary plaque change of NCL in patients with different stages of chronic kidney disease (CKD) using intravascular ultrasound (IVUS) and integrated backscatter IVUS (IB-IVUS). In 113 patients (113 NCLs) underwent both IVUS-guided PCI and follow-up IVUS, volumetric IVUS analyses were performed at proximal reference NCLs in de novo target vessels post PCI and at 8-month follow-up. NCLs were divided into 4 groups based on baseline CKD stage: CKD-1, n = 18; CKD-2, n = 42; CKD-3, n = 29; and CKD4-5, n = 24. We compared serial changes of plaque burden and composition among groups under statin treatment. Plaque progression occurred in CKD-3 (+4.6 mm(3), p < 0.001) and CKD4-5 (+9.8 mm(3), p < 0.001) despite anti-atherosclerotic treatment, whereas plaque regression occurred in CKD-1 (-5.4 mm(3), p = 0.002) and CKD-2 (-3.2 mm(3), p = 0.001) mainly due to initiate statin treatment after PCI. Plaque volume change was correlated with eGFR (p < 0.0001). Multivariate analysis showed CKD stage 3-5 was an independent predictor of plaque progression. Regarding IB-IVUS analyses, lipid plaque increased in CKD-3 (+4.6 mm(3), p < 0.001) and CKD4-5 (+5.4 mm(3), p < 0.001), but decreased in CKD-2 (-2.7 mm(3), p < 0.05). Fibrotic plaque also increased in CKD4-5 (+3.4 mm(3), p < 0.001). Moderate to advanced CKD was associated with coronary plaque progression characterized by greater lipid and fibrotic plaque volumes in NCL under statin treatment after culprit PCI.

A rare case of myocardial infarction related to diagnostic intravascular ultrasound.

A 71-year-old man underwent intracoronary stent implantation for acute inferior myocardial infarction (MI). Immediately after diagnostic intravascular ultrasound (IVUS) at 8 months' follow-up, an acute occlusion of the sinus node (SN) artery appeared, which developed sinus arrest with junctional escape rhythm. The serum level of high-sensitivity troponin T (TpT) was markedly elevated on the day after the procedure (2.1-32.5 ng/l), which was indicative of MI related to IVUS. Under continuous intravenous infusion of unfractionated heparin, the escape rhythm changed to lower atrial rhythm on the 4th day, and recovered to sinus rhythm on the 14th day. Coronary angiography (CAG) on 15th day showed a recanalization of the SN artery, but optical coherence tomography identified that disrupted plaque and white thrombus still existed in the ostium of the SN artery. The patient was discharged on maintenance anticoagulation therapy. We hypothesized from this case that IVUS-related myocardial injury may exist without clinical problems. Our retrospective investigation showed that the median levels of high-sensitivity TpT in 20 patients who underwent CAG and subsequent diagnostic IVUS significantly increased from 0.6 (interquartile range 0.3-1.1) to 1.6 (0.7-3.6) ng/l (P < 0.05), suggesting that IVUS may induce very low levels of myocardial injury. In conclusion, we experienced a rare case of IVUS-related MI caused by an acute occlusion of the SN artery. This case reaffirms that we should pay more attention to manipulation of IVUS catheters.

Coronary arterial remodeling and out-stent plaque change after drug-eluting stent implantation--comparison between zotarolimus-eluting stents and paclitaxel-eluting stents.

BACKGROUND: Out-stent plaque characteristics and eosinophilic inflammatory response, which correlates with positive remodeling after first-generation drug-eluting stent implantation, may be associated with late restenosis and very late stent thrombosis. The differences of out-stent plaque characteristics were compared between paclitaxel-eluting stents (PES) and zotarolimus-eluting stents (ZES), using integrated backscatter-intravascular ultrasound (IB-IVUS). METHODS AND RESULTS: Of 78 patients enrolled, 25 receiving PES and 25 receiving ZES had adequate IVUS assessment. Volumetric IVUS analysis was performed after stenting and at 8-month follow-up. Out-stent plaque change in the stented segment was compared on IB-IVUS. The relationship between systemic inflammatory response and out-stent plaque change was evaluated. In PES, vessel volume significantly increased (365-389 mm(3), P<0.0001), whereas it did not change in ZES (315-314 mm(3), P=0.81). In culprit lesions at baseline in PES, fibrous plaque tended to increase (3.1-3.6mm(2), P=0.051) and lipid plaque significantly increased (4.3-5.1mm(2), P=0.02), whereas in ZES the fibrous plaque significantly increased (2.9-4.0mm(2), P<0.0001) but lipid plaque significantly decreased (5.1-3.6mm(2), P<0.0001). Systemic eosinophil increase was significantly correlated with positive remodeling and out-stent lipid plaque increase. CONCLUSIONS: Chronic out-stent plaque change in ZES consisted of less positive remodeling and more favorable effects on out-stent plaque characteristics than PES. Systemic eosinophil change might be a marker of out-stent lipid plaque change.

Association of seasonal variation in the prevalence of metabolic syndrome with insulin resistance.

The aim of this study was to examine the hypothesis that seasonal variation in the prevalence of metabolic syndrome (MetS) is associated with increased insulin resistance. Among 840 Japanese male workers who were evaluated using the homeostasis model assessment of insulin resistance (HOMA-IR) in June (summer) 2010, we prospectively studied a total of 758 subjects (40-65 years of age) who underwent an assessment in December (winter) 2010. MetS was defined according to the criteria proposed by the International Diabetes Federation (IDF) and the Japanese Society of Internal Medicine (JSIM). The median level of HOMA-IR in the study subjects was 0.84 (interquartile range: 0.60-1.19). The prevalence rates of IDF- and JSIM-MetS significantly increased from 12.4 and 9.6% in the summer to 16.6 and 13.3% in the winter, respectively (each P<0.05). Our data suggest that these increases are mainly due to increases in blood pressure (BP) and glucose during the winter assessment. The prevalence rates of IDF-MetS in the first, second, third and fourth quartiles of HOMA-IR were 1.1, 5.8, 14.3 and 29.1% in the summer and 3.1, 10.6, 21.9, and 31.3% in the winter, respectively. Similar results were obtained when using the JSIM criteria. In the third quartile, the frequency of elevated BP increased from 42.4% in the summer to 61.2% in the winter (P<0.05), and these values were mainly correlated with significant variations in IDF- and JSIM-MetS prevalence rates. This study demonstrates that seasonal variation in MetS prevalence is associated with mildly to moderately increased insulin resistance in middle-aged Japanese men.

Successful coronary intervention for spontaneous coronary dissection in a patient with fibromuscular dysplasia.

Spontaneous coronary artery dissection (SCAD) is a reported rare cause of acute coronary syndrome (ACS) and sudden death among middle-aged women. Some institutes have recently reported fibromuscular dysplasia (FMD) concomitant with SCAD. Therefore, a survey of the presence of comorbid FMD in SCAD patients is important to obtain a definitive diagnosis and for the prediction of possible SCAD recurrence. The optimal treatment of ACS due to SCAD remains undetermined, and technical failures are frequently encountered in primary percutaneous coronary intervention (PCI) owing to the unusual non-atherosclerotic cause of the disease. We report a case of SCAD successfully treated with cutting balloon PCI under intravascular ultrasound guidance without stent implantation, in which FMD was detected in the right external iliac artery through screening by noncoronary angiography, not duplex ultrasound. .

Proposed cutoff level of waist circumference in Japanese men: evaluation by homeostasis model assessment of insulin resistance levels.

OBJECTIVE: The aim of this study is to propose the cutoff level of waist circumference (WC) on the basis of homeostasis model assessment of insulin resistance (HOMA-IR) levels in order to diagnose metabolic syndrome (MetS). METHODS: We examined a total of 798 non-diabetic men (40-65 years of age) by using a receiver operating characteristic (ROC) curve to determine the cutoff level that yielded the maximum sensitivity plus specificity. According to the criteria proposed by the International Diabetes Federation (IDF), and the Japanese Society of Internal Medicine (JSIM), subjects with ≥ 2 metabolic components other than abdominal obesity, were considered to have MetS. RESULTS: The overall prevalence rates of IDF- and JSIM-MetS were 17.4% (n=139) and 15.5% (n=124), respectively. The median levels of WC and HOMA-IR were 83.1 [interquartile range (IQR): 78.5-88.4] cm and 0.84 (IQR: 0.61-1.19), respectively. HOMA-IR was highly correlated with each metabolic parameter (each p<0.05), and in addition, multiple linear regression analysis of HOMA-IR (adjusted R2=0.459) showed that WC level was the strongest independent predictors of HOMA-IR level (F=141.1, p<0.05). According to ROC curve analysis, the cutoff level of HOMA-IR for predicting IDF- and JSIM-MetS was 0.92 for both (sensitivity: 79.9% and 78.2%, specificity: 64.9% and 63.6%). Based on the HOMA-IR level, the proposed WC cutoff level was 82.7 cm (sensitivity: 75.4%, specificity: 63.8%). CONCLUSION: This study suggests that WC level should be more strictly managed than current criteria, for preventing the development of MetS in non-diabetic middle-aged Japanese men.

Evaluation of in-stent neointimal tissue components using integrated backscatter intravascular ultrasound: comparison of drug-eluting stents and bare-metal stents.

Although in-stent restenosis (ISR) occurs after drug-eluting stents (DES) implantation, neointimal tissue characteristics have not been fully investigated. We assessed neointimal tissue components using integrated backscatter intravascular ultrasound (IB-IVUS) after DES and bare-metal stents (BMS) implantation. Fifty-seven consecutive patients with 61 lesions underwent repeated percutaneous coronary intervention (PCI) for the treatment of ISR (DES: 24 lesions, BMS: 37 lesions). PCI was performed using plain old balloon angioplasty (POBA). Before PCI, we assessed neointimal tissue characteristics using IB-IVUS. Neointima was divided into four categories: category 1 (-11 to -29 dB), category 2 (-29 to -35 dB), category 3 (-35 to -49 dB), and category 4 (-49 to -130 dB) according to IB values. We compared neointimal tissue components between DES and BMS. Thirty-three patients with 33 lesions (DES: 17, BMS: 16) were finally included. Neointima was predominantly composed of category 3 tissue in both groups (DES: 68 ± 8%, BMS: 73 ± 5%, P = 0.053). DES had a broader distribution of category 4 tissue component than BMS. After POBA, distal slow flow phenomenon occurred in 5 of DES (29%), whereas none of BMS. In DES, the optimal threshold of category 4 tissue to predict distal slow flow phenomenon after POBA was 30% (sensitivity: 100%, specificity: 92%). Neointima was mainly composed of category 3 tissue at ISR site, irrespective of DES or BMS. In DES, there was a subgroup with category 4 rich tissue, which caused distal slow flow phenomenon after POBA. IB-IVUS might be useful to identify vulnerable neointima in DES restenosis.

Intravascular ultrasound and histopathological observations in a patient with very late sirolimus-eluting stent thrombosis.

This case report describes an autopsy case of very late stent thrombosis, which was associated with intravascular ultrasound findings of late-acquired stent malapposition with thrombotic materials and marked positive vascular remodeling at the site of the sirolimus-eluting stent implantation. Histopathological examination showed both destructive and proliferative reactions had occurred in the same stented coronary arterial wall 44 months after sirolimus-eluting stent implantation. Long-lasting severe local inflammation beyond healing reaction, causing vessel enlargement, may be related to very late stent thrombosis.

Effect of intravascular ultrasound-guided adjuvant high-pressure non-compliant balloon post-dilation after drug-eluting stent implantation.

Drug-eluting stent (DES) expansion characteristics after aggressive high-pressure post-dilation using a non-compliant (NC) balloon have not been fully investigated. We evaluated 58 patients with native coronary lesions treated with DESs [24 paclitaxel eluting stents (PES) and 34 sirolimus-eluting stents (SES)]. After post-dilation (12-14 atm) using a stent-mounted semi-compliant balloon to reduce stent edge injury, adjuvant high-pressure post-dilation using NC balloon was performed within the stents. Stent size, stent length, and NC balloon size were selected based on preinterventional intravascular ultrasound (IVUS) assessment. Stent underexpansion was defined according to criteria of the Multicenter Ultrasound Stenting in Coronaries (MUSIC) study as a minimal stent cross-sectional area <90% of the average reference lumen area. Resultant endpoint was to obtain optimal stent expansion. Serial changes of stent expansion and stent symmetry were calculated in each group. After stent-mounted semi-compliant balloon post-dilation, both stents could not achieve adequate percent stent expansion (PES 73 ± 18% vs. SES 67 ± 9%, p = 0.38). After high-pressure post-dilation using an NC balloon, percent stent expansion was 97 ± 14% in PES and 91 ± 13% in SES, respectively (p = 0.25). Axial stent symmetry indices also significantly improved in both groups. Although radial stent symmetry indices improved significantly in PES group, those in the SES group had no significant changes. Finally, frequency of stent underexpansion significantly reduced, 87-20% in PES and 92-15% in SES, respectively (p = 0.01) without any significant stent edge injury. DES expansion improved safely after adjuvant high-pressure post-dilation using an NC balloon under IVUS guidance.