Performance of a Novel CT-Derived Fractional Flow Reserve Measurement to Detect Hemodynamically Significant Coronary Stenosis.

BACKGROUND: Fractional flow reserve (FFR) based on computed tomography (CT) has been shown to better identify ischemia-causing coronary stenosis. However, this current technology requires high computational power, which inhibits its widespread implementation in clinical practice. This prospective, multicenter study aimed at validating the diagnostic performance of a novel simple CT based fractional flow reserve (CT-FFR) calculation method in patients with coronary artery disease. METHODS: Patients who underwent coronary CT angiography (CCTA) within 90 days and invasive coronary angiography (ICA) were prospectively enrolled. A hemodynamically significant lesion was defined as an FFR ≤ 0.80, and the area under the receiver operating characteristic curve (AUC) was the primary measure. After the planned analysis for the initial algorithm A, we performed another set of exploratory analyses for an improved algorithm B. RESULTS: Of 184 patients who agreed to participate in the study, 151 were finally analyzed. Hemodynamically significant lesions were observed in 79 patients (52.3%). The AUC was 0.71 (95% confidence interval [CI], 0.63-0.80) for CCTA, 0.65 (95% CI, 0.56-0.74) for CT-FFR algorithm A (P = 0.866), and 0.78 (95% CI, 0.70-0.86) for algorithm B (P = 0.112). Diagnostic accuracy was 0.63 (0.55-0.71) for CCTA alone, 0.66 (0.58-0.74) for algorithm A, and 0.76 (0.68-0.82) for algorithm B. CONCLUSION: This study suggests the feasibility of automated CT-FFR, which can be performed on-site within several hours. However, the diagnostic performance of the current algorithm does not meet the a priori criteria for superiority. Future research is required to improve the accuracy.

Clinical safety and effectiveness of the Genoss drug-eluting stent in real-world clinical practice.

BACKGROUND/AIMS: The Genoss DES™ is a novel, biodegradable, polymer-coated, sirolimus-eluting stent with a cobalt- chromium stent platform and thin strut. Although the safety and effectiveness of this stent have been previously investigated, real-world clinical outcomes data are lacking. Therefore, the aim of this prospective, multicenter trial was to evaluate the clinical safety and effectiveness of the Genoss DES™ in all-comer patients undergoing percutaneous coronary intervention. METHODS: The Genoss DES registry is a prospective, single-arm, observational trial for evaluation of clinical outcomes after Genoss DES™ implantation in all-comer patients undergoing percutaneous coronary intervention from 17 sites in South Korea. The primary endpoint was a device-oriented composite outcome of cardiac death, target vessel-related myocardial infarction (MI), and clinically driven target lesion revascularization (TLR) at 12 months. RESULTS: A total of 1,999 patients (66.4 ± 11.1 years of age; 72.8% male) were analyzed. At baseline, 62.8% and 36.7% of patients had hypertension and diabetes, respectively. The implanted stent number, diameter, and length per patient were 1.5 ± 0.8, 3.1 ± 0.5 mm, and 37.0 ± 25.0 mm, respectively. The primary endpoint occurred in 1.8% patients, with a cardiac death rate of 1.1%, target vessel-related MI rate of 0.2%, and clinically driven TLR rate of 0.8%. CONCLUSION: In this real-world registry, the Genoss DES™ demonstrated excellent safety and effectiveness at 12 months among all-comer patients undergoing percutaneous coronary intervention. These findings suggest that the Genoss DES™ may be a viable treatment option for patients with coronary artery disease.

Validation of the diagnostic performance of 'HeartMedi V.1.0', a novel CT-derived fractional flow reserve measurement, for patients with coronary artery disease: a study protocol.

INTRODUCTION: Coronary CT angiography (CCTA) is widely used for non-invasive coronary artery evaluation, but it is limited in identifying the nature of functional characteristics that cause ischaemia. Recent computational fluid dynamic (CFD) techniques applied to CCTA images permit non-invasive computation of fractional flow reserve (FFR), a measure of lesion-specific ischaemia. However, this technology has limitations, such as long computational time and the need for expensive equipment, which hinder widespread use. METHODS AND ANALYSIS: This study is a prospective, multicentre, comparative and confirmatory trial designed to evaluate the diagnostic performance of HeartMedi V.1.0, a novel CT-derived FFR measurement for the detection of haemodynamically significant coronary artery stenoses identified by CCTA, based on invasive FFR as a reference standard. The invasive FFR values ≤0.80 will be considered haemodynamically significant. The study will enrol 184 patients who underwent CCTA, invasive coronary angiography and invasive FFR. Computational FFR (c-FFR) will be analysed by CFD techniques using a lumped parameter model based on vessel length method. Blinded core laboratory interpretation will be performed for CCTA, invasive coronary angiography, invasive FFR and c-FFR. The primary objective of the study is to compare the area under the receiver-operator characteristic curve between c-FFR and CCTA to non-invasively detect the presence of haemodynamically significant coronary stenosis. The secondary endpoints include diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value and correlation of c-FFR with invasive FFR. ETHICS AND DISSEMINATION: The study has ethic approval from the ethics committee of Seoul National University Bundang Hospital (E-1709/420-001) and informed consent will be obtained for all enrolled patients. The result will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: KCT0002725; Pre-results.

Safety and Efficacy of a New Ultrathin Sirolimus-Eluting Stent with Abluminal Biodegradable Polymer in Real-World Practice.

BACKGROUND AND OBJECTIVES: Recently, Genoss drug-eluting stent (DES)™ stent comprising cobalt-chromium platform with an ultrathin strut thickness, sirolimus, and an abluminal biodegradable polymer was developed. Owing to the lack of substantial evidence for the safety and efficacy of this stent, we report 12-month results of the Genoss DES™ stent. METHODS: We analyzed subjects who were eligible for a 12-month follow-up from the ongoing Genoss DES™ registry, which is a prospective, single-arm, observational, multicenter trial to investigate the clinical outcomes after the successful Genoss DES™ stent implantation among all-comers. The primary endpoint was a device-oriented composite outcome, defined as cardiac death, target vessel-related myocardial infarction, and target lesion revascularization at 12-month follow-up. RESULTS: Among 622 subjects, the mean age of subjects was 66.5±10.4 years, 70.6% were males, 67.5% had hypertension, and 38.3% had diabetes. The implanted stent number, diameter, and length per patient were 1.5±0.8, 3.1±0.4 mm, and 36.0±23.3 mm, respectively. At 12-month clinical follow-up, the primary endpoint occurred only in 4 (0.6%) subjects. CONCLUSIONS: The novel Genoss DES™ stent exhibited excellent safety and efficacy in real-world practice.

A prospective randomized clinical study evaluating the efficacy and compliance of oral sulfate solution and 2-L ascorbic acid plus polyethylene glycol.

BACKGROUND/AIMS: Oral sulfate solution (OSS) is an emerging cleansing agent for bowel preparation. However, data comparing OSS to other conventional bowel preparations in Asian patients are limited. Therefore, the objective of this study was to compare the efficacy and tolerability of OSS to ascorbic acid plus polyethylene glycol (AA + PEG) in Asian patients. METHODS: This was a prospective, randomized, parallel, investigator-blind study performed in two university hospitals in Korea. Bowel preparation efficacy was evaluated using both the Ottawa Bowel Preparation Scale (OBPS) and Boston Bowel Preparation Scale (BBPS). RESULTS: Among 173 patients, 86 received OSS while 87 received AA + PEG for bowel preparation. Total OBPS score was 2.80 ± 2.48 in the OSS group and 4.49 ± 3.08 in the AA + PEG group, indicating significantly (p < 0.001) better efficacy with OSS. Total BBPS was higher in the OSS group (7.43 ± 1.49 vs. 6.51 ± 1.76, p < 0.001), indicating superior bowel preparation quality with OSS. Preparation-related adverse events were generally acceptable. Patients receiving OSS had more nausea (1.92 ± 0.94 vs. 1.54 ± 0.76, p = 0.004) and abdominal cramping (1.45 ± 0.78 vs. 1.17 ± 0.51, p = 0.006) than those receiving AA + PEG. However, overall satisfaction and taste were similar between the two groups. CONCLUSION: OSS had a non-inferior bowel cleansing efficacy than AA + PEG regardless of colon segment.

Outcomes and clinical relevance of stool multiplex bacterial polymerase chain reaction in patients with acute diarrhea: single center experience.

BACKGROUND/AIMS: Diagnostic stool multiplex polymerase chain reaction (PCR) testing has attracted considerable interest, because of its high sensitivity, short turnaround time, and ability to detect multiple organisms simultaneously. This study investigates the clinical usefulness of a stool multiplex bacterial PCR in patients with acute diarrhea. METHODS: We retrospectively evaluated the stool multiplex bacterial PCR results, clinical parameters, and clinical courses of patients hospitalized because of acute diarrhea between August 2014 and November 2016. RESULTS: A total of 725 patients (male, 372; mean age, 30.9 ± 29.3 years) underwent stool multiplex bacterial PCR. A total of 243 pathogens were detected in 226 patients. The detection rate of multiplex PCR testing was higher than that of stool culture (32.7% vs. 3.3%, p < 0.01). Severe symptoms of acute diarrhea (bloody diarrhea, frequent diarrhea) and prescribed empirical antibiotics were significantly more common in the positive multiplex PCR group (p = 0.02, p < 0.01, p < 0.01, respectively). However, mean durations of hospital stay were similar in the 2 groups according to the multiplex PCR results (p = 0.32). In addition, Campylobacter spp., which was the most commonly detected pathogen (97/243, 39.9%), was significantly associated with frequent diarrhea and prescribed empirical antibiotics (p < 0.01), but not with duration of hospital stay (p = 0.09). CONCLUSION: We concluded that stool multiplex bacterial PCR might be a useful tool for identifying bacterial etiology in patients with acute diarrhea, especially in those with Campylobacter spp. infection.

Clinical value of procalcitonin for suspected nosocomial bloodstream infection.

BACKGROUND/AIMS: Procalcitonin (PCT) may prove to be a useful marker to exclude or predict bloodstream infection (BSI). However, the ability of PCT levels to differentiate BSI from non-BSI episodes has not been evaluated in nosocomial BSI. METHODS: We retrospectively reviewed the medical records of patients ≥ 18 years of age with suspected BSI that developed more than 48 hours after admission. RESULTS: Of the 785 included patients, 105 (13.4%) had BSI episodes and 680 (86.6%) had non-BSI episodes. The median serum PCT level was elevated in patients with BSI as compared with those without BSI (0.65 ng/mL vs. 0.22 ng/mL, p = 0.001). The optimal PCT cut-off value of BSI was 0.27 ng/mL, with a corresponding sensitivity of 74.6% (95% confidence interval [CI], 66.4% to 81.7%) and a specificity of 56.5% (95% CI, 52.7% to 60.2%). The area under curve of PCT (0.692) was significantly larger than that of C-reactive protein (CRP; 0.526) or white blood cell (WBC) count (0.518). However, at the optimal cut-off value, PCT failed to predict BSI in 28 of 105 cases (26.7%). The PCT level was significantly higher in patients with an eGFR < 60 mL/min/1.73 m2 than in those with an eGFR ≥ 60 mL/min/1.73 m2 (0.68 vs. 0.17, p = 0.01). CONCLUSIONS: PCT was more useful for predicting nosocomial BSI than CRP or WBC count. However, the diagnostic accuracy of predicting BSI remains inadequate. Thus, PCT is not recommended as a single diagnostic tool to avoid taking blood cultures in the nosocomial setting.

Spontaneous Bleeding from Internal Pudendal Artery associated with Abciximab after Primary Percutaneous Coronary Intervention: Successful Treatment with Percutaneous Gel-Foam Embolization.

We describe a case of spontaneous bleeding from a branch of the right internal pudendal artery that resulted in massive scrotal swelling in a patient who had underwent primary percutaneous coronary intervention with the use of abciximab concurrent with conventional anticoagulation and dual antiplatelet therapies for the treatment of acute ST-segment elevation myocardial infarction. This unusual complication was promptly identified by percutaneous peripheral arteriography and successfully treated with gel-foam embolization.

A vegetarian diet does not protect against nonalcoholic fatty liver disease (NAFLD): A cross-sectional study between Buddhist priests and the general population.

BACKGROUND/AIMS: There is limited data that supports a role for a vegetarian diet in nonalcoholic fatty liver disease (NAFLD). The aim of this study is to evaluate the relationship between vegetarian diets and NAFLD, considering metabolic syndrome and obesity. MATERIALS AND METHODS: This is a cross-sectional, retrospective study comparing the prevalence of NAFLD of 615 Buddhist priests and age-, sex-, Body mass index (BMI)-and presence/absence of metabolic syndrome-matched controls who underwent routine health checkups in a health promotion center. Diagnosis and severity of NAFLD was determined based on ultrasonographic findings. RESULTS: The prevalence of NAFLD was not statistically significantly different between the Buddhist priests and the general population (29.9% vs. 25.05%, p=0.055). The Buddhist priest group had higher serum albumin, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), and serum triglyceride levels and lower serum total bilirubin, serum fasting glucose, and serum high density lipoprotein (HDL) levels than the general population group. In univariate analysis and multivariate analysis, NAFLD was associated with old age, male gender, increased BMI, increased waist circumference, metabolic syndrome, high albumin, high glucose, high AST, high ALT, high gamma glutamyl transpeptidase (GGT), high triglycerides, low HDL, high low density lipoprotein (LDL), and high total cholesterol. CONCLUSION: The vegetarian diet does not protect against NAFLD.

Colistin treatment in carbapenem-resistant Acinetobacter baumannii pneumonia patients: Incidence of nephrotoxicity and outcomes.

Colistimethate sodium (CMS) is increasingly used to treat multidrug-resistant Gram-negative bacilli infections. However, the incidence of CMS-associated nephrotoxicity has not been evaluated in patients with carbapenem-resistant Acinetobacter baumannii (CRAB) pneumonia. This retrospective study included 120 patients with CRAB pneumonia treated with intravenous CMS for ≥72 h. The objective of the study was to determine risk factors for CMS-induced nephrotoxicity and 30-day mortality in patients with CRAB pneumonia. Of the 120 patients with CRAB pneumonia, 61 (51%) developed nephrotoxicity. Multivariate analysis showed that dose per ideal body weight (IBW) [odds ratio (OR)=1.28, 95% confidence interval (CI) 1.01-1.62; P=0.04], Charlson co-morbidity index (OR=1.31, 95% CI 1.06-1.60; P=0.01) and septic shock (OR=3.16, 95% CI 1.32-7.60; P=0.01) were associated with CMS-associated nephrotoxicity. Thirty-day mortality was 33% (39/120). Multivariate analysis showed that higher daily doses of CMS per IBW [hazard ratio (HR)=0.81, 95% CI 0.67-0.98; P=0.03] and longer duration of CMS therapy (HR=0.86, 95% CI 0.79-0.95; P=0.002) were associated with increased survival. Septic shock (HR=3.91, 95% CI 1.95-7.83; P<0.001) and corticosteroid use (HR=3.49, 95% CI 1.67-7.28; P=0.001) were associated with decreased survival in patients with CRAB pneumonia. Higher daily doses of CMS per IBW, Charlson comorbidity index and septic shock were significant risk factors for CMS-associated nephrotoxicity. However, CMS-associated nephrotoxicity does not appear to have an impact on mortality.

Effect of anemia correction on left ventricular structure and filling pressure in anemic patients without overt heart disease.

BACKGROUND/AIMS: There are few data on the effects of low hemoglobin levels on the left ventricle (LV) in patients without heart disease. The objective of this study was to document changes in the echocardiographic variables of LV structure and function after the correction of anemia without significant cardiovascular disease. METHODS: In total, 34 iron-deficiency anemia patients (35 ± 11 years old, 32 females) without traditional cardiovascular risk factors or cardiovascular disease and 34 age- and gender-matched controls were studied. Assessments included history, physical examination, and echocardiography. Of the 34 patients with anemia enrolled, 20 were followed and underwent echocardiography after correction of the anemia. RESULTS: There were significant differences between the anemia and control groups in LV diameter, left ventricular mass index (LVMI), left atrial volume index (LAVI), peak mitral early diastolic (E) velocity, peak mitral late diastolic (A) velocity, E/A ratio, the ratio of mitral to mitral annular early diastolic velocity (E/E'), stroke volume, and cardiac index. Twenty patients underwent follow-up echocardiography after treatment of anemia. The follow-up results showed significant decreases in the LV end-diastolic and end-systolic diameters and LVMI, compared with baseline levels. LAVI, E velocity, and E/E' also decreased, suggesting a decrease in LV filling pressure. CONCLUSIONS: Low hemoglobin level was associated with larger cardiac chambers, increased LV, mass and higher LV filling pressure even in the subjects without cardiovascular risk factors or overt cardiovascular disease. Appropriate correction of anemia decreased LV mass, LA volume, and E/E'.

Controlling mold releasing propensity--the role of surface energy and a multiple chain transfer agent.

As the desired feature size of mold-assisted lithography decreases rapidly efficient demolding process becomes more challenging due to strong adhesion between polymeric resists and fine-featured molds. We synthesized new macromolecular additives and investigated the effects of surface energy and contraction of resist materials on demolding propensity by monitoring the adhesion force between the resist and the applied mold. The resist's surface energy was controlled, as inferred from water contact angle measurements, by chemically modifying its hydroxyl functionality. The resist's degree of volume shrinkage during the photocuring procedure was also controlled by mixing in a newly developed chemical that has a multiple radical chain transfer capability. The adhesion force was proportionally reduced as the surface energy of the resist materials decreased and as the volume shrinkage was reduced. When the volume shrinkage control was applied in conjunction with the low surface energy resist material (LS-30UV), we obtained an optimized condition requiring a minimum force for releasing the mold from the cured resist layer.

Delayed ventricular septal rupture after percutaneous coronary intervention in acute myocardial infarction.

In the era before reperfusion therapy, ventricular septal rupture complicated 1approximate3% of acute myocardial infarctions (AMI) usually 3-5 days after onset. Studies have reported a positive correlation between the incidence of septal perforation and total occlusion of the coronary arteries. A 70-year old female patient was referred to the emergency room with the diagnosis of acute anterior myocardial infarction (MI) and recent cerebral infarction. The coronary angiogram showed a 90% stenosis at the mid-portion of the left anterior descending artery (LAD), and the lesion was successfully treated by percutaneous coronary intervention (PCI) with stent implantation. After PCI, the anterior wall motion improved on the follow-up echocardiogram. However, on the 20th hospital day, the patient condition deteriorated suddenly with pulmonary congestion. The echocardiography revealed a 1.3 cm ventricular septal defect at the apical septum with a left-to-right shunt. We report this rare case of delayed septal rupture in a patient with patent LAD after PCI and recovery of wall motion.

Glomerular crescents are responsible for chronic graft dysfunction in post-transplant IgA nephropathy.

Information is limited regarding the histological features related to chronic graft dysfunction and failure in patients with IgA nephropathy developing after renal transplantation. The prevalence and significance of glomerular crescents in post-transplant IgAN including recurrent, de novo and transmitted forms (TxIgAN), were studied. Renal morphology was evaluated in 71 patients of TxIgAN, obtained at more than 6 months post-transplant, and compared with regard to the presence (C-TxIgAN) or absence (N-TxIgAN) of glomerular crescents. Crescents were demonstrated in 12 samples of 10 patients (14.1%). The percentages of crescents were from 4.8% to 83.3% (median, 28.6%) in each sample. Ten samples of C-TxIgAN had cellular to fibrocellular crescents, and four of these were associated with diffuse mesangial proliferation. Serum creatinine levels and the frequency of nephrotic range proteinuria at the time of biopsy and the degree of interstitial inflammation were significantly different in the two groups. Graft survival after allograft biopsies was significantly lower in C-TxIgAN (P = 0.0017). Chronic rejection was a major cause of graft loss in N-TxIgAN (31.8%), whereas TxIgAN was the major cause in C-TxIgAN (66.7%). In conclusion, the current study suggests that glomerular crescents are not rare and that they are responsible for chronic graft dysfunction in TxIgAN patients.

Gastric adenocarcinoma after renal transplantation.

BACKGROUND/AIMS: Little is known of the characteristics of gastric adenocarcinoma after renal transplantation. This study was performed to find out the incidence and clinicopathological features of gastric adenocarcinoma after renal transplantation in an endemic area for gastric cancer. METHODOLOGY: Between April 1979 and March 2001, fourteen gastric adenocarcinoma patients (0.7%) out of 2000 renal transplant recipients in a single institute were retrospectively reviewed. RESULTS: Gastric adenocarcinoma was identified in 14 recipients (8 males and 6 females; mean age 47.6 years) about 60 months after renal transplantation. Four patients had early gastric cancer; ten patients had cancer in an advanced stage. Eleven patients underwent surgical resection, while three with distant metastasis were treated symptomatically. There was no postoperative mortality. Seven patients survived without evidence of recurrence, whereas four died of recurrence and three of gastric cancer progression. CONCLUSIONS: Renal transplant recipients are at increased risk of gastric adenocarcinoma, the most common malignancy in Korea. With curative surgery, favorable prognosis can be anticipated when the diagnosis is made at an early stage. Regular endoscopic examination for early diagnosis is recommended during the follow-up period after renal transplantation in a gastric cancer endemic area.

Postoperative liver regeneration and complication in live liver donor after partial hepatectomy for living donor liver transplantation.

The safety of donor is the first priority during whole procedure in living donor liver transplantation. We evaluated the short-term results of partial living donor liver transplantation in the view of donor safety. We prospectively evaluated the extent of liver regeneration, the recovery of liver function, and the perioperative complications in 41 live liver donors for partial liver transplantation at our institution. We developed novel personal computer volumetry program for the evaluation of liver regeneration. Serial CAT scan was performed preoperatively, at postoperative day (POD) #7 and POD #30 and liver volume was measure by using volumetry program. The serum level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin (T.bil.) was serially monitored. There were 34 males and 7 females. The mean preoperative liver volume was 1320.6 cm3. The remained mean liver volume was 687.8 cm3 after harvest, and increased to 954.4 cm3 (144.6%) at POD #7, and 1169.5 cm3 (81.4%) at POD #30, which was 88.5% of preoperative total liver volume. The serum level of ALT/ AST and T.bil. peaked at POD #1 and declined thereafter, and finally returned to preoperative level at POD #30. The regeneration rate was significantly different by age, type and size of graft according to the donors. Six donors experienced postoperative complications and they were four pleural effusions, one wound infection and one case of bile duct stenosis that was treated by endoscopic nasal biliary drainage. All of them were right lobe donors. In conclusion, the donor liver regenerated up to 88.5% of preoperative volume with full recovery of liver function at POD #30. Right lobe donors suffered more complications and need more meticulous operative and postoperative care than left lobe or left lateral segment donors.

Autoantibody against, malondialdehyde-modified low density lipoprotein in patients with non-diabetic unstable angina: a potential role in immunologic reaction of plaque instability.

The role of autoantibody against oxidized low-density lipoprotein (LDL) in the pathogenesis of atherosclerosis is still unknown. The purpose of this study was to determine whether autoantibodies against malondialdehyde (MDA)-modified LDL are associated with coronary artery disease (CAD) and clinical presentations of CAD in non-diabetic patients without acute myocardial infarction (AMI). We determined the serum levels of autoantibody against MDA-modified LDL by ELISA in 71 patients with angiographically significant CAD (> or = 50% diameter stenosis in at least 1 vessel) and 80 controls without angiographically significant CAD. Among the total 151 subjects, 30 subjects did not have any clinical ischemic event, 90 subjects had stable angina symptoms, and 31 subjects had unstable angina symptoms. The autoantibody titer, expressed mean optical density units, was significantly higher in patients with CAD than in controls (0.177 +/- 0.014 versus 0.127 +/- 0.011, respectively; p=0.006) and higher in unstable angina group than in stable angina group (0.240 +/- 0.025 versus 0.145 +/- 0.007, respectively; p < 0.001). By logistic regression analysis, the high autoantibody titer was associated significantly with CAD (P=0.008), independent of age, gender, body mass index, triglyceride concentration, and the ratio of total cholesterol-high density lipoprotein (HDL) cholesterol. In multiple regression analysis, presence of CAD, smoking history and low HDL-cholesterol level were independent factors associated with a increased anti-oxLDL Ab titer. The autoantibody titer was significantly lower in nonsmoker than smoker (p=0.019) and higher in low HDL- cholesterol (< or = 35 mg/dl) group than in high HDL-cholesterol group (p=0.012). Elevated autoantibody titer was associated with CAD and the unstable clinical presentation of CAD. Our results suggest that immune response to oxidized LDL may play a role in the pathogenesis of atherosclerosis and plaque instability.