Tissue characteristics of neointima in late restenosis: integrated backscatter intravascular ultrasound analysis for in-stent restenosis.

Although late restenosis is one of the long-term complications of stent implantation, its pathogenesis has not been fully elucidated. For consecutive patients who developed in-stent restenosis (ISR) after stent implantation, integrated backscatter (IB) intravascular ultrasound was performed for ISR lesions. The tissue characteristics of neointima within the stented segment were compared between lesions with early restenosis and those with late restenosis. Of 73 ISR lesions arising after sirolimus-eluting stent (SES; n = 25) or bare-metal stent (BMS; n = 48) implantation, early and late restenosis were documented in 52 and 21 lesions, respectively. A higher prevalence of late restenosis was observed after SES implantation than after BMS implantation (60.0 vs. 12.5 %; p < 0.001). The duration between stent implantation and late restenosis was significantly shorter after SES implantation than after BMS implantation (57.0 ± 22.1 vs. 124.4 ± 19.6 months; p < 0.001). Percent low-IB volume was significantly higher in the neointima of late restenosis than in that of early restenosis (29.9 ± 9.9 vs. 19.8 ± 11.3 %; p < 0.001). Significantly more low-IB tissue was observed in the neointima of late restenosis than in that of early restenosis, suggesting atherosclerotic progression in late phase after stent implantation as a possible mechanism of late restenosis.

Impact of lesion characteristics on the prediction of optimal poststent fractional flow reserve.

BACKGROUND: Poststent fractional flow reserve (FFR) is a useful indicator of optimal percutaneous coronary intervention, and higher poststent FFR is associated with favorable long-term clinical outcome. However, little is known about the factors influencing poststent FFR. The purpose of this study was to determine the impact of lesion characteristics on poststent FFR. METHODS: For patients who had scheduled stent implantation for stable angina, FFR measurements at maximum hyperemia were performed before and after coronary stent implantation. As one of lesion characteristics, the FFR pressure drop pattern was evaluated and classified as either an abrupt or a gradual pattern according to the pullback curve of FFR. RESULTS: A total of 205 lesions with physiological significant stenosis were evaluated. Fractional flow reserve value increased from 0.67±0.10 to 0.87±0.07 after stent implantation. Optimal poststent FFR was achieved in 75 lesions (36.6%). Logistic regression analysis demonstrated that optimal poststent FFR was positively correlated with an abrupt pressure drop pattern (hazard ratio [HR] 2.11, 95% CI 1.06-4.15, P=.03) and prestent FFR (HR 1.04, 95% CI 1.03-2.04, P=.03; per 0.1 increase), and negatively correlated with lesion localization to the left anterior descending artery (HR 0.18, 95% CI 0.09-0.36, P<.0001). The c statistic for predicting optimal poststent FFR was 0.763 (95% CI 0.702-0.819). CONCLUSION: Abrupt pressure drop patterns, prestent FFR, and lesion localization to the left anterior descending artery were independent predictors of optimal poststent FFR.

Effects of eicosapentaenoic acid on peri-procedural (type IVa) myocardial infarction following elective coronary stenting.

OBJECTIVES: The aim of this study was to assess the effect of eicosapentaenoic acid (EPA) on peri-procedural (type IVa) myocardial infarction (MI) following elective percutaneous coronary intervention (PCI). METHODS AND RESULTS: We analyzed data from 165 of 178 consecutive patients with stable angina pectoris who underwent de novo successful stent implantation in the native coronary artery. Patients were assigned to receive statin therapy in combination with 1800mg/day of EPA or statin alone. Post-procedural index of microcirculatory resistance (IMR) values were calculated for 30 patients in the EPA group and 32 controls. In the multivariate logistic model, EPA administration, low kidney function, and the presence of slow flow/no reflow were significantly and independently associated with type IVa MI. Post-procedural IMR values were significantly lower in the EPA group [19.8 (6.4, 51.1) vs. 27.8 (8.2, 89.3), p=0.003] compared to the control group. CONCLUSIONS: Pre-treatment with EPA in addition to statins significantly reduced the incidence of type IVa MI compared to statin therapy only, which may be attributed to the ability of EPA to reduce microvascular dysfunction induced by PCI.

Impact of cigarette smoking on coronary plaque composition.

OBJECTIVES: Cigarette smoking is associated with atherosclerosis and is an important risk factor for cardiovascular disease. We evaluated the impact of cigarette smoking on coronary plaque composition using integrated backscatter intravascular ultrasound (IB-IVUS). METHODS: A total of 143 consecutive patients undergoing percutaneous coronary intervention were enrolled. A history of illness, as well as smoking habits, was obtained by interview. Participants were asked to report whether they were current smokers, had quit smoking, or had never smoked. According to interview results, patients were divided into the following three groups: current, former, and never smokers. Conventional and IB-IVUS tissue characterization analyses were carried out. Three-dimensional analyses were carried out to determine plaque volume and the volume of each plaque component (lipid, fibrous, and calcified). RESULTS: IB-IVUS analysis indicated that the patients in the current smoker group had significantly increased percent lipid volume and significantly decreased percent fibrous volume (P=0.01 and 0.03). Logistic regression analysis showed that the current smoking state (odds ratio 3.51, 95% confidence interval 1.02-12.10, P=0.04) was independently associated with the presence of lipid-rich plaques, which was defined as the upper 75th percentile of the study population. CONCLUSION: Smoking is independently associated with lipid-rich plaques, contributing to the increasing risk for plaque vulnerability.

Severity of morphological lesion complexity affects fractional flow reserve in intermediate coronary stenosis.

BACKGROUND: Although functional ischemia identification is important when determining revascularization, angiographic assessment alone is challenging in intermediate coronary stenosis. Previous studies have reported that lesion-specific characteristics affected the fractional flow reserve (FFR). However, the relationship between morphological lesion complexity and FFR has not yet been fully evaluated. This study aimed to evaluate the impact of morphological lesion complexity on FFR in intermediate coronary stenosis. METHODS: A total of 109 consecutive patients with 136 intermediate coronary stenoses (visually estimated diameter stenosis: 40-70%) were assessed via quantitative coronary angiography, lesion-specific characteristics, and FFR. Indexed lesions were assessed according to 6 morphological lesion characteristics: eccentricity, bend, irregularity, calcification, bifurcation, and diffuse. The lesions were then classified into 3 groups according to the morphological severity count represented by the number of present characteristics (mild-complex: 0-1, moderate-complex: 2-3, and severe-complex: 4-6), and their functional severities were evaluated. Lesions with an FFR <0.80 were considered functionally significant coronary stenoses. RESULTS: Of the 136 lesions, 51% were located in the left anterior descending artery (LAD) and 47% had an FFR <0.80. The FFR differed significantly among the 3 lesion complexity groups (0.84±0.10 vs. 0.79±0.10 vs. 0.73±0.07, for mild-, moderate-, and severe-complex, respectively; p<0.01). In a multivariate logistic analysis, LAD lesions, moderate- and severe-complex, and diameter stenosis were independently associated with an FFR <0.80 [odds ratio (OR): 5.65, 95% confidence interval (CI): 2.50-12.80, p<0.01; OR: 2.96, 95% CI: 1.30-6.72, p<0.01; OR: 7.11, 95% CI: 1.25-40.37, p=0.03, and OR: 2.65, 95% CI: 1.04-6.72, p=0.04, respectively]. CONCLUSIONS: Both indexed vessels and the degree of diameter stenosis affected the FFR. In addition, the severity of morphological lesion complexity correlated with the degree of functional severity in intermediate coronary stenosis.

Feasibility and safety of intracoronary nicorandil infusion as a novel hyperemic agent for fractional flow reserve measurements.

Fractional flow reserve (FFR) is a useful modality to assess the functional significance of coronary stenoses. Although adenosine triphosphate (ATP) is generally used as the hyperemic stimulus, we sometimes encounter adverse events like hypotension during FFR measurement. Nicorandil, an ATP-sensitive potassium channel opener, recognized as an epicardial and resistance vessel dilator, has not been fully evaluated as a possible alternative hyperemic agent. The aim of this study was to evaluate the feasibility and safety of intracoronary nicorandil infusion compared to intravenous ATP for FFR measurement in patients with coronary artery disease. A total of 102 patients with 124 intermediate lesions (diameter stenosis >40 and <70% by visual assessment) were enrolled. All vessels underwent FFR measurements with both ATP (150 µg/kg/min) and nicorandil (2.0 mg) stimulus. FFR, hemodynamic values, and periprocedural adverse events between the two groups were evaluated. A strong correlation was observed between FFR with ATP and FFR with nicorandil (r = 0.954, p < 0.001). The agreement between the two sets of measurements was also high, with a mean difference of 0.01 ± 0.03. The mean aortic pressure drop during pharmacological stimulus was significantly larger with ATP compared to nicorandil (9.6 ± 9.6 vs. 5.5 ± 5.8 mmHg, p < 0.001). During FFR measurement, transient atrioventricular block was frequently observed with ATP compared to nicorandil (4.0 vs. 0%, p = 0.024). This study suggests that intracoronary nicorandil infusion is associated with clinical utility and safety compared to ATP as an alternative hyperemic agent for FFR measurement.

Non-invasive assessment of functionally significant coronary stenoses through mathematical analysis of spectral ECG components.

OBJECTIVES: The aim of this study was to evaluate the accuracy of the Multifunction CardioGram (MCG) in detecting the presence of functionally significant coronary ischaemia. METHODS AND RESULTS: This prospective study evaluated the accuracy of the MCG, a new ECG analysis device used to diagnose ischaemic coronary artery disease (CAD). A consecutive 112 participants suspected to have CAD who were scheduled for elective coronary angiography (CAG) from October 2012 to December 2013 were examined. Their predictive values of relevant ischaemia were measured by MCG, standard ECG and Framingham Risk Score (FRS) and compared. Five levels of ischaemia based on CAG findings adjusted by fractional flow reserve (FFR) values and three levels of MCG score of high, borderline or low were used. The MCG (OR=2.67 (1.60 to 4.44), p<0.001) was the only test significantly associated with ischaemia level. The FFR values for individual MCG scores with low, borderline and high were 0.77 (0.70 to 0.86), 0.78 (0.71 to 0.82) and 0.69 (0.65 to 0.77), respectively, p=0.042. A high MCG score had a specificity of 90.4% (87.0% to 93.9%) in model 1 adjusted by FFR≤0.8 threshold and of 87.0% (83.2% to 90.8%) in model 2 adjusted by FFR≤0.75 threshold, and a negative predictive value of 82.5% (78.3% to 86.7%) in model 1 and of 83.8% (79.6% to 87.9%) in model 2 for the prediction of severe ischaemia. CONCLUSIONS: The MCG showed high specificity with a high negative predictive value, suggesting that the MCG could be used not only to identify functionally significant ischaemia but to reduce unnecessary CAGs. TRIAL REGISTRATION NUMBER: UMIN ID: 000009992.

Effects of polyunsaturated fatty acids on periprocedural myocardial infarction after elective percutaneous coronary intervention.

AIMS: The aim of this study was to address the association of lipid profiles with periprocedural myocardial infarction (pMI) after elective percutaneous coronary intervention (PCI). METHODS AND RESULTS: Of the 302 consecutive patients who received elective PCI at the Chubu Rosai Hospital, Nagoya, Japan between June 2009 and December 2010, data from 231 native coronary lesions were analysed. Various biomarkers including serum troponin T (TnT), eicosapentaenoic acid (EPA), arachidonic acid (AA), and low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol were measured at baseline and at 18 hrs after PCI. pMI was defined as a post-procedural increase of TnT >3 times above the upper normal limit. Patients with pMI had significantly lower EPA/AA (0.25 [0.19-0.28] vs. 0.45 [0.21-0.62], p<0.001) and higher LDL/HDL cholesterol (3.00±1.05 vs. 2.36±0.90, p=0.008) than patients without pMI. On multivariate logistic analysis, EPA/AA per 0.1 increase (hazard ratio [HR] 0.62, 95% CI: 0.43-0.88, p=0.007), LDL/HDL (HR 1.92, 95% CI: 1.15-3.19, p=0.012), stented length (HR 1.40, 95% CI: 1.07-1.83, p=0.015), and the presence of unstable angina pectoris (UAP) (HR 8.89, 95% CI: 2.83-27.9, p<0.001) were significantly and independently associated with the incidence of pMI. CONCLUSIONS: EPA/AA and LDL/HDL were significantly associated with pMI after PCI, creating the possibility of a new therapeutic target of pMI.

Plasma indoxyl sulfate and estimated glomerular filtration rate.

BACKGROUND: Indoxyl sulfate (IS), a uremic toxin, has cardiovascular as well as uremic toxicity. We evaluated the prognostic value of blood IS level for long-term outcome. METHODS AND RESULTS: This study followed 311 patients with coronary artery disease. Plasma IS level and estimated glomerular filtration rate (eGFR) were determined. The endpoint was a major adverse cardiac event (MACE). Median follow-up was 759 days. IS was significantly higher in patients with MACE than in those without (P<0.001). Patients were divided according to quartiles (Q) of plasma IS level (Q1, Q2, Q3, and Q4). On Kaplan-Meier analysis a significantly lower MACE-free rate was obtained for Q4 compared with the other quartiles (P<0.001). In patients with eGFR ≥90, 89-60, 59-30, 29-15, and <15 ml·min(-1)·1.73 m(-2), the percentage of patients in Q4 was 0%, 13%, 29%, 100%, and 100%, respectively. In patients with eGFR 89-60 ml·min(-1)·1.73 m(-2), there was no significant difference in MACE-free rate between Q4 and the other quartiles; in patients with eGFR 59-30 ml·min(-1)·1.73 m(-2), a significantly lower MACE-free rate was obtained for Q4 compared with the other quartiles (P=0.832 and P=0.015, respectively). CONCLUSIONS: Plasma IS level is a significant predictor of MACE, especially in patients with eGFR 59-30 ml·min(-1)·1.73 m(-2).

Relation of omega-3 fatty acid and C-reactive protein to peripheral artery disease in patients with coronary artery disease.

Eicosapentaenoic acid (EPA), a member of the omega-3 polyunsaturated fatty acid family, prevents cardiovascular disease. C-reactive protein (CRP) is a marker of inflammation, which promotes atherosclerosis. The aim of this study was to investigate the relationship among EPA, CRP, and the prevalence of peripheral artery disease (PAD), which is a manifestation of systemic atherosclerosis. A cross-sectional study was performed on 238 patients with coronary artery disease (CAD). Blood EPA and CRP levels and ankle-brachial pressure indices were measured. Cut-off values for plasma EPA levels and serum CRP levels were determined using receiver operating characteristic (ROC) analysis. Patients with ABIs ≤0.9 were defined as having PAD. EPA levels were significantly lower and CRP levels were significantly higher in patients with PAD than in those without [48 (26-77) vs. 58 (41-83) µg/ml, p = 0.026 and 3.3 (0.64-14.0) vs. 0.70 (0.32, 2.4) mg/l, p = 0.004]. Multivariate analysis for PAD revealed that high CRP levels and low EPA levels were significant and independent predictors of PAD [odds ratio 3.1 (95 % CI 1.4-6.9), p = 0.006 and odds ratio 4.9 (95 % CI 1.5-9.7), p = 0.004]. Furthermore, to predict PAD, adding high CRP levels and low EPA levels to the established risk factors significantly improved the area under the ROC curves, from 0.66 to 0.78, of the PAD prediction model (p = 0.004). A significant relationship among EPA, CRP, and PAD was confirmed in patients with CAD.

Prognostic impact of lipid contents on the target lesion in patients with drug eluting stent implantation.

We sought to determine the morphologic predictors of major adverse cardiac events (MACEs) after successful percutaneous coronary intervention (PCI) with drug-eluting stents (DES), using integrated backscatter intravascular ultrasound (IB-IVUS). Conventional IVUS and IB-IVUS were performed in 260 consecutive patients who underwent PCI with DES. Three-dimensional analyses were performed to determine plaque volume and the volume of each plaque component (lipid, fibrous, and calcification). Patients were divided into two groups according to the median lipid volume (LV) in the target lesion. MACEs were defined as death, nonfatal myocardial infarction, and any repeat revascularization. The median follow-up interval was 1285 days. MACEs were observed in 64 patients (24.6 %). Patients having a larger LV compared with their counterparts had worse long-term clinical outcomes regarding mortality (3.8 vs. 0 %, P = 0.02) and MACEs (31.5 vs. 17.7 %, P = 0.008) by log-rank test. After adjustment for confounders, large LV (odds ratio 1.95, 95 % confidence interval 1.14-3.33, P = 0.02) was significantly and independently associated with MACEs. The assessment of coronary plaque characteristics in the target lesion may be useful to predict long-term outcome following successful coronary intervention.

Post-stress perfusion abnormalities detected on myocardial perfusion single-photon emission computed tomography predict long-term mortality after elective abdominal aortic aneurysm repair.

BACKGROUND: After abdominal aortic aneurysm (AAA) repair, relatively low survival during long-term follow-up remains an unresolved issue. Stress myocardial perfusion single-photon emission computed tomography (SPECT) well predicts future mortality overall, as well as providing diagnoses of coronary artery disease. The prognostic value of myocardial SPECT findings after AAA repair, however, remains unclear. METHODS AND RESULTS: This study followed 285 patients, all undergoing preoperative pharmacologic stress myocardial perfusion SPECT to determine summed stress score (SSS), then elective AAA repair by open AAA repair or endovascular aneurysm repair. The endpoint of the study was cardiac death. The median follow-up duration was 925 days (range, 541-1,095 days). Twenty-four (8%) died during follow-up. Kaplan-Meier analysis showed that patients with SSS≥9 had a significantly poorer prognosis than those with SSS<9 (76% vs. 93%, P=0.003). Multivariate Cox proportional hazards analysis indicated that SSS≥9, diabetes, and chronic kidney disease≥stage 3 could significantly and independently predict long-term cardiovascular mortality in patients after AAA repair (hazard ratio [HR], 4.2; 95% confidence interval [CI]: 1.8-9.7, P=0.001; HR, 3.0; 95% CI: 1.2-7.4, P=0.020; and HR, 4.1; 95% CI: 1.7-10.1, P=0.029, respectively). CONCLUSIONS: Preoperative pharmacologic stress myocardial perfusion SPECT is a useful method to predict long-term cardiovascular mortality for patients undergoing elective AAA repair.

Association of inflammatory markers with the morphology and extent of coronary plaque as evaluated by 64-slice multidetector computed tomography in patients with stable coronary artery disease.

We evaluated the association between inflammatory markers and coronary artery plaque assessed by 64-slice multidetector computed tomography. Coronary computed tomography angiography was performed in patients with chest discomfort suggestive of coronary artery disease (CAD). Individuals with an acute coronary syndrome were excluded from the study. Coronary plaque morphology, the number of artery segments exhibiting plaque, and the number of vessels with >50% stenosis were evaluated. Plasma levels of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), plasminogen activator inhibitor-1, and vascular endothelial growth factor were measured. Among the 178 patients studied (age 65 ± 10 years; 70% men), 125 were diagnosed with CAD. Hs-CRP and IL-6 concentrations were significantly higher in patients with CAD than in patients without (2.73 ± 4.7 vs. 1.32 ± 2.6 mg/L, P = 0.018, and 3.06 ± 3.3 vs. 2.19 ± 2.4 pg/mL, P = 0.036). The IL-6 level was high in patients with predominantly calcified plaque, and was significantly higher in patients with 4-9 plaque segments than in those with no or 1-3 plaque segments (4.07 ± 5.3 vs. 2.19 ± 2.4 pg/mL and 2.43 ± 2.0 pg/mL, respectively, P = 0.025). The number of stenotic vessels was not significantly related to inflammatory markers. Multivariate logistic analysis revealed that plasma levels of hs-CRP but not IL-6 were associated with the presence of coronary plaque with calcification (OR 3.37, P = 0.026). This study supports the usefulness of inflammatory markers for the evaluation of coronary plaque in patients with stable CAD.

Differences in tissue characterization of restenotic neointima between sirolimus-eluting stent and bare-metal stent: integrated backscatter intravascular ultrasound analysis for in-stent restenosis.

AIMS: The pathogenesis of in-stent restenosis (ISR) after drug-eluting stent (DES) implantation remains unclear. The purpose of this study is to analyse tissue characterizations of neointima in restenosis lesions after sirolimus-eluting stent (SES), comparing with those after bare metal stent (BMS) using integrated backscatter intravascular ultrasound (IB-IVUS). METHODS AND RESULTS: A total of 54 consecutive patients who had ISR lesions after SES (n = 20) or BMS (n = 34) implantation were enrolled. For tissue characterization of neointima, IB-IVUS was performed by cross-sectional (at the minimum lumen area) and volumetric (within the stented segment) analyses. In addition, angiographic patterns of restenosis were evaluated with division into focal and diffuse. The focal angiographic pattern of restenosis was predominantly observed in the SES group (SES vs. BMS; 80.0 vs. 26.5%; P = 0.0001), whereas the diffuse pattern was more common in the BMS group (SES vs. BMS; 20.0 vs. 73.5%; P = 0.0001). On both cross-sectional and volumetric IB-IVUS analyses, the neointimal tissue in restenosis lesions after SES implantation had a significantly larger percentage of lipid tissue (cross-sectional: 23.3 ± 12.7 vs. 15.7 ± 11.9%; P = 0.033; volumetric: 22.8 ± 10.4 vs. 16.3 ± 7.0%; P = 0.008) and a significantly smaller percentage of fibrous tissue compared with that after BMS implantation (cross-sectional: 73.6 ± 11.6 vs. 82.0 ± 11.2%; P = 0.011, volumetric: 73.8 ± 9.5 vs. 80.5 ± 6.7%; P = 0.004). CONCLUSION: This IB-IVUS study indicates that larger amounts of lipid tissue are present in neointima of SES when compared with BMS, suggesting that neoatherosclerosis may in part be responsible for ISR after SES implantation.

Relation of plasma indoxyl sulfate levels and estimated glomerular filtration rate to left ventricular diastolic dysfunction.

The prognosis of patients with diastolic heart failure (HF) is as poor as that of patients with systolic HF. Greater chronic kidney disease-associated mortality occurs in patients with left ventricular (LV) diastolic HF than in those with systolic HF. Indoxyl sulfate (IS), a uremic toxin, directly affects cardiac cells adversely in in vitro experiments. We investigated the association of IS, a uremic toxin, and chronic kidney disease with LV diastolic dysfunction in the clinical setting. The present study included 204 consecutive patients with preserved LV systolic function. To evaluate LV function, all patients underwent echocardiography. To measure the plasma IS levels and estimated glomerular filtration rate (eGFR), blood samples were obtained. Of the 204 patients, 75 (37%) had LV diastolic dysfunction. A significantly lower prevalence of LV diastolic dysfunction was present in patients with lower plasma IS levels (≤1.0 µg/ml) than those with greater plasma IS levels (38 [29%] vs 37 [51%], p <0.001). Furthermore, a significantly lower prevalence of LV diastolic dysfunction was present in patients with lower plasma IS levels and preserved eGFR than those with greater plasma IS levels and preserved eGFR, those with lower plasma IS levels and a reduced eGFR, or those with greater plasma IS levels and reduced eGFR (20 [21%] vs 18 [53%], p = 0.001; 20 [21%] vs 18 [46%], p = 0.004; and 20 [21%] vs 19 [56%], p <0.001, respectively). In conclusion, greater plasma IS levels or a reduced eGFR, or both, represent an increased risk of LV diastolic dysfunction.

Morphologic characterization and quantification of superficial calcifications of the coronary artery--in vivo assessment using optical coherence tomography.

Coronary calcification is proportional to the extent and severity of atherosclerotic disease, and is a predictor of cardiac events. Furthermore, coronary calcification protruding into the lumen is considered as one type of vulnerable plaque. Optical coherence tomography (OCT) can provide in vivo imaging of the detailed vessel wall structure of the coronary artery with high resolution, as in the histological approach. We analyzed coronary calcification in that fashion using OCT in vivo. This study consisted of 70 superficial coronary calcifications of 39 consecutive patients who underwent percutaneous coronary intervention. After revascularization, OCT was performed in the treated vessel. We analyzed morphologic characteristics and the quantification of OCT-determined coronary calcification. Superficial coronary calcifications were classified into two groups depending on whether they did not intrude the lumen (type I) or did (type II). The distance from the lumen and the volume of each calcification were then measured. Superficial coronary calcifications were classified into two groups; type I, n = 39 (56%) and type II, n = 31 (44%). Type II calcifications were located significantly closer to the lumen [80 microm (60-130) vs.130 microm (90-260), p = 0.015], and tended to be smaller, but did not show a significant difference [0.65 (0.2631.3) mm3 vs. 1.2 (0.47-1.9) mm3, p = 0.153] compared to those of type I. In conclusion, OCT could visualize superficial coronary calcifications in detail and enable us to evaluate in vivo morphologic characterizations and quantify them.