Jae-Bin Seo

The Recanalization of Chronic Total Occlusion Leads to Lumen Area Increase in Distal Reference Segments in Selected Patients : An Intravascular Ultrasound Study

OBJECTIVES This study sought to investigate the extent of and factors related to lumen and vessel area change in coronary arteries after total occlusion (TO) recanalization. BACKGROUND TO of a coronary artery promotes negative remodeling in distal reference segments. Recanalization can restore blood flow, potentially leading to positive vascular remodeling. METHODS From March 2005 to June 2008, 58 consecutive patients with de novo TO lesions of at least 1-month duration were enrolled. We performed intravascular ultrasound after successful percutaneous coronary intervention and at the 6-month follow-up, and we quantified changes in the distal reference segments. RESULTS At the 6-month follow-up, there was a significant increase in the mean lumen diameter (+0.21 mm, p = 0.001), the mean external elastic membrane diameter (+0.13 mm, p = 0.010), the lumen area (+0.87 mm(2), p < 0.001), and the external elastic membrane area (+0.85 mm(2), p = 0.001) in the distal reference segments and an increase in the left ventricular ejection fraction (+2.77%, p = 0.010). Overall, 40 of 58 patients (69%) showed lumen area increase; these patients had increase in lumen diameter by 0.40 ± 0.34 mm (p < 0.001) and increase in incomplete stent apposition rate (p = 0.006). A TO duration of longer than 3 months (odds ratio [OR]: 14.8; 95% confidence interval [CI]: 1.28 to 172.8, p = 0.032), a poor collateral flow (OR: 12.0; 95% CI: 1.92 to 74.2, p = 0.008), and statin use (OR: 7.4; 95% CI: 1.03 to 53.6, p = 0.047) were independent predictors of lumen area increase. CONCLUSIONS Recanalization of TO led to lumen area increase in two-thirds of the patients. Independent predictors of lumen area increase were occlusion duration, a poor collateral flow, and statin use. These factors could be used as guides in choosing the optimal stent size during percutaneous coronary intervention to TO lesions and optimal medical therapy during follow-up.

The association between arterial stiffness and left ventricular filling pressure in an apparently healthy Korean population

BackgroundThe aim of this study is to investigate the association between arterial stiffness and left ventricular filling pressure in an apparently healthy Korean population.MethodsA total of 115 healthy subjects without known cardiovascular risk factors or overt heart disease who underwent both transthoracic echocardiography and brachial-ankle pulse wave velocity (baPWV) measurement at the same day during their routine check-ups were analyzed.ResultsThe mean age of study subjects was 52.8 ± 8.4 years, and 78 (67.8%) were men. The mean baPWV value was 1,325 ± 185 cm/s. Study subjects were divided into 3 groups according to E/E’ value: subjects with E/E’ < 8, 8–12.9 and E/E’ ≥ 13. As E/E’ increased, baPWV value increased gradually: baPWV in subjects with E/E’ < 8, E/E’ 8–12.9 and E/E’ ≥ 13, were 1,261 ± 163, 1,345 ± 169, 1,569 ± 232 cm/s, respectively (p < 0.001). In multiple linear regression analyses, baPWV was significantly associated with E/E’ (β = 0.371, p < 0.001) after controlling confounders including age, sex and body mass index. In receiver-operating characteristic (ROC) curve analysis, the sensitivity and specificity for detection of E/E’ ≥ 10 were 78.6% and 59.8%, respectively with mean baPWV of 1,282 cm/s as the cut off value. The discriminatory capacity for predicting E/E’ ≥ 10 was improved from an area under the ROC curve of 0.646 with age alone to 0.734 when baPWV was added (p < 0.001).ConclusionsThere is a significant association between baPWV and E/E’ in an apparently healthy Korean population. BaPWV is useful as a simple and non-invasive method for early detection of increased LV filling pressure among these people.

Clinical characteristics of coronary drug-eluting stent fracture: insights from a two-center des registry.

Stent fracture (SF) has been implicated as a risk factor for in-stent restenosis, but its incidence and clinical characteristics are not well established. Therefore we investigated the conditions associated with stent fracture and its clinical presentation and outcome. Between 2004 and 2007, consecutive cases of SF were collected from the Seoul National University Hospital. Clinical characteristics and outcome of patients with fractured stents were compared with a ten-fold cohort of age and gender matched controls (n = 236). A total of 4,845 patients received percutaneous coronary intervention and 3,315 patients (68.4%) underwent angiographic follow-up. Twenty-eight fractured stents were observed in 24 patients. The incidence of SF was 0.89% for sirolimus-eluting stents (SES) and 0.09% for paclitaxel-eluting stents. Chronic kidney disease, stent implantation in the right coronary artery (RCA), and SES use were independent predictors of drug-eluting stent fracture by multivariate analysis. SF was significantly associated with binary restenosis (11.4% vs 41.7%, P < 0.001) and increased risk of target lesion revascularization (8.1% vs 33.3%, P = 0.001). Patients with SF but without significant restenosis showed excellent outcome despite only medical treatment. In conclusion, SF is associated with increased rates of restenosis and repeat revascularization. Significant risk factors include chronic kidney disease, RCA intervention, and SES use.

The incidence and predictors of postprocedural incomplete stent apposition after angiographically successful drug-eluting stent implantation†

Objectives: The aim of this study was to evaluate the incidence and predictors of postprocedural incomplete stent apposition (ISA) after angiographically successful drug‐eluting stent (DES) implantation. Background: The deployed stents are usually evaluated by angiography alone; however, there are possibilities of postprocedural ISA despite the angiographically successful implantation. Methods: A total of 339 lesions in which poststent intravascular ultrasound (IVUS) was performed after successful DES implantation was included. Paclitaxel‐eluting stents were implanted in 237 lesions and sirolimus‐eluting stents (SES) in 102 lesions. Clinical, angiographic and procedural characteristics and IVUS findings for all cases were analyzed. Results: The overall incidence of ISA was 13.9% (47/339). By multivariate analysis, male gender (OR: 2.36, 95% CI: 1.09–5.11), deployment of SES (OR: 2.90, 95% CI: 1.49–5.67), the presence of intracoronary thrombus (OR: 7.47, 95% CI: 1.67–33.47), and non‐ST elevation myocardial infarction (OR: 2.73, 95% CI: 1.09–6.83) were independent predictors for postprocedural ISA after angiographically successful DES implantation. Conclusions: The incidence of postprocedural ISA after angiographically successful implantation of DES was not infrequent. A DES deployment strategy incorporating IVUS guidance might be helpful to reduce the incidence of postprocedural ISA.

Incremental Prognostic Value of Brachial-Ankle Pulse Wave Velocity to Single-Photon Emission Computed Tomography in Patients with Suspected Coronary Artery Disease.

AIM Arterial stiffness assessed by brachial-ankle pulse wave velocity (baPWV) is predictive of cardiovascular events. This study was designed to investigate whether baPWV has an additional prognostic value to single-photon emission computed tomography (SPECT) in patients with suspected coronary artery disease (CAD). METHODS A total of 350 subjects (age, 66.2 ± 10.5 years, 53.4% male) with suspected CAD undergoing myocardial SPECT and baPWV within 30 days were retrospectively analyzed. Cardiovascular events, including cardiovascular death, acute coronary syndrome and ischemic stroke, were assessed. Both fixed and reversible perfusion defects on SPECT were considered abnormal myocardial perfusion imaging (MPI) findings. RESULTS During the median follow-up period of 441 days (interquartile range 169-719 days), cardiovascular events occurred in 21 patients (6.0%). In multivariable Cox regression analysis, abnormal MPI [hazard ratio (HR), 2.67; 95% confidence interval (CI), 1.21-10.37; p=0.024] and high baPWV (≥ 1,790 cm/s) (HR, 2.03; 95% CI, 1.08-6.38; p=0.007) were independent predictors of clinical events even after adjusting for possible confounders. Also, high baPWV had an incremental prognostic value to traditional risk factors and abnormal MPI in predicting cardiovascular events (overall Chi-square, from 24.08 to 27.42; p ＜ 0.001). Kaplan-Meier survival curves stratified by baPWV and MPI proved significantly improved prediction of cardiovascular events (log-rank p=0.001). CONCLUSIONS baPWV has an incremental prognostic value to traditional risk factors and MPI. Therefore, baPWV can be used to identify subjects at higher risk of cardiovascular events in patients undergoing SPECT.

The Effect of Aspirin on C-Reactive Protein in Hypertensive Patients

High level of C-reactive protein (CRP), most popular inflammatory marker, increases the risk of thrombotic cardiovascular events. Aspirin, which has both anti-inflammatory and anti-thrombotic effects, has the potential to influence CRP release. Several studies have been reported investigating clinical effects of aspirin on CRP levels. Some studies have reported aspirin reduced CRP levels, but other studies did not. This study was designed to assess the effect of low-dose aspirin on CRP levels in controlled hypertensive patients who had low inflammatory burden. Two hundred twenty-five patients with controlled hypertension were randomly divided into two groups; aspirin group (n = 122, 100 mg of aspirin) and the control group (n = 134). Patients with a CRP level >1 mg/dL (10 mg/L) were excluded because these high levels suggest infection. C-reactive protein level and lipid profiles were measured before therapy and 3 months after therapy. There were no differences in baseline clinical characteristics between the two groups. Low-dose aspirin showed no significant influence on CRP levels over 3 months (from 0.10 ± 0.0099 to 0.12 ± 0.0097 mg/dL, p = 0.12). Statin therapy did not influence CRP levels. Aspirin-resistance also had no influence on CRP levels. We conclude that low-dose aspirin has no significant effect on decreasing CRP levels in the patients with controlled hypertension which had low inflammatory burden. The anti-inflammatory mechanism may not play an important role in the cardioprotective effect of aspirin in the population with low inflammatory burden such as controlled hypertensive patients.

The Association of Brachial-Ankle Pulse Wave Velocity with Coronary Artery Disease Evaluated by Coronary Computed Tomography Angiography

The aim of this study was to investigate whether brachial-ankle pulse wave velocity (baPWV) is associated with the severity of coronary artery disease (CAD) assessed by coronary computed tomography angiography (CCTA), and to evaluate baPWV as a predictor of obstructive CAD on CCTA. A total of 470 patients who underwent both baPWV and CCTA were included. We evaluated stenosis degree and plaque characteristics on CCTA. To estimate the severity of CAD, we calculated the number of segment with plaque (segment involvement score; SIS), stenosis degree-weighted plaque score (segment stenosis score; SSS), and coronary artery calcium score (CACS). The mean baPWV was 1,485 ± 315 cm/s (range, 935-3,175 cm/s). Non-obstructive (stenosis < 50%) and obstructive (stenosis ≥ 50%) CAD was found in 129 patients (27.4%) and 144 (30.6%), respectively. baPWV in patients with obstructive CAD was higher than that of patients with non-obstructive (1,680 ± 396 cm/s versus 1,477 ± 244 cm/s, P < 0.001) or no CAD (1,680 ± 396 cm/s versus ± 196 1,389 cm/s, P < 0.001). baPWV showed significant correlation with SSS (r = 0.429, P < 0.001), SIS (r = 0.395, P < 0.001), CACS (r 0.346, P < 0.001), and the number of segment with non-calcified plaque (r 0.092, P = 0.047), mixed plaque (r = 0.267, P < 0.001), and calcified plaque (r = 0.348, P < 0.001), respectively. The optimal baPWV cut-off value for the detection of obstructive CAD was 1,547 cm/s. baPWV ≥ 1,547 cm/s was independent predictor for the obstructive CAD. In conclusion, baPWV is well correlated with the severity of CAD evaluated by CCTA. baPWV has the potential to predict severity of coronary artery atherosclerosis.

The effects of metabolic syndrome and its components on arterial stiffness in relation to gender

OBJECTIVES The influence of gender-dependent metabolic risk factors on arterial stiffness has not been fully determined. This study was performed to investigate the relationship between components of metabolic syndrome and brachial-ankle pulse wave velocity (baPWV) according to gender. METHODS A total of 537 subjects (54.4±7.5 years and 70.6% men) who underwent baPWV measurement during routine check-ups were analyzed. RESULTS BaPWV was 1363±229cm/s in men and 1387±269cm/s in women (p=0.313). The prevalence of metabolic syndrome was not different according to gender (23% in men versus 27% in women, p=0.335). In multiple linear regression analyses, after adjustment for age, baPWV was significantly associated with systolic and diastolic blood pressures, fasting glucose, and triglyceride in both genders. Waist circumference was associated with baPWV in women but not in men. High-density lipoprotein levels were not associated with baPWV in either gender. Subjects with metabolic syndrome had a higher baPWV than those without metabolic syndrome for women aged <55 years, but not for all men and women aged ≥55 years. As the number of the components of metabolic syndrome increased, baPWV increased proportionally in both genders. However, this correlation was more strong in women than that in men (β=0.408 versus β=0.146 after adjustment for age). CONCLUSION In middle-aged Koreans, women showed stronger associations between each component of metabolic syndrome and baPWV than men. The association of each component of metabolic syndrome to arterial stiffness may differ between men and women.

Influence of Second- and Third-Degree Heart Block on 30-Day Outcome Following Acute Myocardial Infarction in the Drug-Eluting Stent Era

This study was conducted to investigate the prognostic value of heart block among patients with acute myocardial infarction (AMI) treated with drug-eluting stents. A total of 13,862 patients with AMI, registered in the nation-wide AMI database from January 2005 to June 2013, were analyzed. Second- (Mobitz type I or II) and third-degree atrioventricular block were considered as heart block in this study. Thirty-day major adverse cardiac events (MACE) including all causes of death, recurrent myocardial infarction, and revascularization were evaluated. Percutaneous coronary intervention with implantation of drug-eluting stent was performed in 89.8% of the patients. Heart block occurred in 378 patients (2.7%). Thirty-day MACE occurred in 1,144 patients (8.2%). Patients with heart block showed worse clinical parameters at initial admission, and the presence of heart block was associated with 30-day MACE in univariate analyses. However, the prognostic impact of heart block was not significant after adjustment of potential confounders (p = 0.489). Among patients with heart block, patients with a culprit in the left anterior descending (LAD) coronary artery had worse clinical outcomes than those of patients with a culprit in the left circumflex or right coronary artery. LAD culprit was a significant risk factor for 30-day MACE even after controlling for confounders (odds ratio 5.28, 95% confidence interval 1.22 to 22.81, p = 0.026). In conclusion, despite differences in clinical parameters at the initial admission, heart block was not an independent risk factor for 30-day MACE in adjusted analyses. However, a LAD culprit was an independent risk factor for 30-day MACE among patients with heart block.

Incidence and Risk Factors Associated With Hospitalization for Variant Angina in Korea.

AbstractThis study aimed to determine the incidence and the risk factors of hospitalization for variant angina (VA) in Korean patients. Using the National Inpatient Sample (NIS) database, manufactured and released by the Health Insurance Review and Assessment Service (HIRA) in Korea, the incidence of hospitalization and rehospitalization for VA were calculated. The numbers of patients hospitalized for VA were estimated to be 14,362 in 2009, 17,492 in 2010, and 20,592 in 2011. The standardized incidence rates of hospitalization for VA were 31.4 per 100,000 people in 2009, 36.5 in 2010, and 41.7 in 2011 (relative increase rate from 2009 to 2011, 33.0%, P for trend < 0.0001). VA patients predominantly belonged to the middle-age group between 40 and 69 years (75.5%), and there were 54.3% male. Based on the hospitalization episodes, the number of rehospitalization was calculated to be 879, 1141, and 1446 patients out of 1867, 2274, and 2677 patients from 2009, 2010, and 2011, respectively. The rates of rehospitalization for VA were 47.1% in 2009, 50.2% in 2010, and 54.0% in 2011 (P for trend < 0.0001). Age was an independent factor associated with rehospitalization for VA. Hospitalization for VA occurred most frequently in fall from 2009 to 2011. In conclusion, hospitalization rates for VA steadily increased from 2009 to 2011 in Korea, and about a half of VA patients was hospitalized more than once a year in 2009 to 2011. Proper health policy and patient education are warranted to control the high rate of hospitalization for VA.