Sun Won Kim

Impact of low-dose aspirin on coronary artery spasm as assessed by intracoronary acetylcholine provocation test in Korean patients.

High-dose aspirin has been reported to aggravate coronary artery spasm (CAS). However, it is unknown whether low-dose aspirin (LDA; 100 mg) has deleterious impact on CAS. We assessed the impact of LDA on CAS induced by intracoronary acetylcholine (ACh) provocation test. A total of 2789 consecutive patients without significant coronary artery disease who underwent ACh test between November 2004 and March 2010 were enrolled. The patients were divided into two groups: the aspirin group taking LDA before ACh test (n=221) and the no aspirin group not taking aspirin (n=2568). At baseline, the prevalence of old age, diabetes mellitus, hypertension, and hyperlipidemia were higher in the aspirin group. During the ACh test, the incidence of significant CAS, ischemic chest pain, as well as severe and multivessel spasm was higher in the aspirin group. The response rate to lower ACh dose was higher in the aspirin group. Multivariate analysis showed that the previous use of LDA was an independent predictor of CAS (adjusted odds ratio, 1.6, 95% confidence interval, 1.0-2.3; p=0.031). However, it is likely that the association of LDA and CAS that we have observed is not causal but may be hypothesis generating due to significant baseline differences. Further, male gender, old age, lipid-lowering drugs, baseline spasm, and myocardial bridge were independent predictors of CAS. LDA was more frequently associated with CAS and ischemic symptoms, as well as severe and multivessel spasm, suggesting the patients who have received LDA would require more intensive medical therapies and close follow up.

Association between aortic calcification and stable obstructive coronary artery disease

BACKGROUND Coronary artery calcification (CAC) is correlated with aortic calcification (AC) and predicts coronary atherosclerosis as well as obstructive coronary artery disease (OCAD). This study aims to investigate whether AC predicts OCAD independent of CAC and its incremental value in predicting OCAD with CAC. METHODS Among the consecutive patients who underwent 64-slice multidetector CT (MDCT), we enrolled 120 stable OCAD (luminal narrowing ≥ 50%) patients and 120 controls without OCAD, matched for cardiovascular risk factors. CAC, thoracic AC, and OCAD were determined by MDCT. RESULTS The prevalence of AC and CAC were significantly higher in OCAD patients than in controls (64% vs. 48%, p = 0.019; 57% vs. 32%, p < 0.001, respectively). There is a significant correlation between AC and CAC scores in the overall study population (r = 0.528, p < 0.001). In univariate analysis, the odds ratios (ORs) of AC and CAC in predicting OCAD were 1.91 (95% CI, 1.14-3.21) and 2.82 (95% CI, 1.67-4.78), respectively. When an adjustment was made for each other, AC did not maintain a significant association with OCAD, whereas CAC persisted the association (OR, 2.52; 95% CI, 1.42-4.47). Both AC and CAC present as compared to both absent was found to be a more potent predictor for OCAD (OR, 3.37; 95% CI 1.78-6.36, p < 0.001) than CAC alone. CONCLUSIONS The presence of AC was associated with stable OCAD independently from cardiovascular risk factors, but the association seemed to be based on the close correlation between AC and CAC. However, AC might have an incremental value with CAC for predicting OCAD.

Effect of StentBoost imaging guided percutaneous coronary intervention on mid-term angiographic and clinical outcomes

INTRODUCTION The gold standard for evaluating stent expansion after percutaneous coronary intervention (PCI) is intravascular ultrasound (IVUS). However, the routine use of this modality is costly and time consuming. StentBoost is a new imaging technique that improves fluoroscopy-based assessments of stent expansion. The purpose of this study was to evaluate the effect of StentBoost imaging-guided PCI on mid-term angiographic and clinical outcomes. METHODS AND RESULTS A total of 870 consecutive patients were recruited (mean age: 64.34 ± 11.61; men: 64.5%), all of whom underwent PCI with drug-eluting stents (DESs). The subjects were divided into a no StentBoost group (n=569 patients) and a StentBoost group (n=301 patients). The 6-month angiographic and 12-month clinical outcomes were compared between the two groups. At 1 month, clinical outcomes were similar between the two groups. At 6 months, the StentBoost group had significantly lower rates of late loss (0.32 ± 0.40 vs. 0.48 ± 0.59; p=0.005) and binary restenosis (1.2% vs. 8.3%; p=0.029) compared with the no-StentBoost group. At 12 months, StentBoost group had significantly lower the incidence of target lesion revascularization (TLR) (1.7% vs. 7%; p=0.034) and TLR-major adverse cardiac events (6% vs. 13.2%; p=0.037) compared with the no-StentBoost group. CONCLUSION We conclude that the routine clinical use of StentBoost during PCI can be useful, and results in better medium-term angiographic and clinical outcomes.

Telmisartan Versus Valsartan in Patients With Hypertension: Effects on Cardiovascular, Metabolic, and Inflammatory Parameters

Background and Objectives Angiotensin-receptor blockers (ARBs) have beneficial effects on cardiovascular, metabolic, and inflammatory parameters in addition to controlling blood pressure (BP). However, few comparative clinical studies have been conducted with different ARBs. We compared these effects in patients with uncomplicated hypertension who were receiving telmisartan or valsartan. Subjects and Methods The subjects were patients with essential hypertension (48.4±9.6 years) who were randomly assigned to take either telmisartan (80 mg/day, n=30) or valsartan (160 mg/day, n=30) for 12 weeks. Their anthropometric, laboratory, vascular, and echocardiographic data were measured at baseline and at the end of the study. Results Baseline characteristics were not significantly different between the two groups, except for the carotid-femoral pulse wave velocity (cfPWV; telmisartan group vs. valsartan group; 841.2±131.0 vs. 761.1±104.4 cm/s, p<0.05). After 12 weeks, BP had fallen to a similar extent with mean reductions in the systolic and diastolic BP of 20.7±18.1 and 16.3±13.0 mm Hg (p<0.001, respectively) for the telmisartan and 22.5±17.0 and 16.8±9.3 mm Hg (p<0.001, respectively) for the valsartan group. Although the cfPWV and left ventricular mass index (LVMI) fell significantly only with the administration of telmisartan, they were not significantly different when baseline cfPWV was considered. The differences in the cfPWV and LVMI changes from baseline between the two groups were also not significant after adjusting for baseline cfPWV. No significant changes in other vascular, metabolic, or inflammatory parameters were observed with either treatment. Conclusion The effects of a 12-week treatment with the two ARBs, telmisartan and valsartan, on cardiovascular, metabolic, and inflammatory parameters were not different in patients with uncomplicated hypertension.

A comparison between central blood pressure values obtained by the Gaon system and the SphygmoCor system.

Central pulse pressure is correlated with carotid atherosclerosis and the incidence of cardiovascular events more significantly than brachial pulse pressure. Augmentation index (Aix) has been shown to be an independent predictor of cardiovascular morbidity and mortality. Pulse wave analysis using the Gaon system allows for the estimation of central blood pressure (CBP), corrected augmentation index (Aix@HR75), ejection duration (ED) and subendocardial viability ratio (SEVR), and is widely used in clinical research in Korea. However, the accuracy of this system is controversial. From February 2008 to March 2011, 99 patients were recruited for this study. Measurements were taken both by the Gaon system and the SphygmoCor system on the same day for all study participants. The estimated values of CBP, Aix@HR75, ED and SEVR for the two systems were compared using paired t-tests, simple correlation analyses and Bland–Altman plots. Systolic blood pressure (SBP) estimated by the two systems was significantly (P<0.001) correlated; the coefficient was 0.982. The two s.d. of the difference in SBP between these systems was quite small—<7 mm Hg. Aix@HR75, ED and SEVR as estimated by the two systems were also significantly correlated, although they, especially SEVR, showed much weaker correlations than were observed in SBP: coefficients for Aix@HR75, ED and SEVR were 0.727, 0.648 and 0.230, respectively. We assessed the CBP of Korean patients estimated by the two systems and observed that the correlations of Aix, ED and SEVR were weaker than that of CBP. Such variations may be due to the difference in measuring methods between the devices. As even a slight change in pulse waveforms may result in a large difference in estimations, parameters, including Aix@HR75, ED and SEVR, should be carefully interpreted by experienced clinicians.

The impact of high sensitivity C-reactive protein level on coronary artery spasm as assessed by intracoronary acetylcholine provocation test.

Purpose High sensitive C-reactive protein (hs CRP) is well known as a strong risk factor of cardiovascular disease (CVD). The aim of this study is to evaluate the impact of elevated hs CRP on coronary artery spasm (CAS) as assessed by intracoronary acetylcholine (ACh) provocation test. Materials and Methods A total of 1729 consecutive patients without significant CVD who underwent coronary angiography and intracoronary ACh test between November 2004 and August 2010 were analyzed. The patients were divided into five groups according to quintiles of hs CRP levels. Results At baseline, the prevalence of elderly, hypertension, diabetes mellitus, current smoking, and lipid levels were higher in patients with higher hs CRP. During ACh test, the incidences of significant CAS, ischemic electrocardiography (EKG) change, multivessel, and diffuse CAS were higher in patients with higher hs CRP. Multivariate analysis showed that the old age (OR=1.01, CI; 1.0-1.02, p=0.0226), myocardial bridge (OR=3.34, CI; 2.16-5.17, p<0.001), and highest quintile hs CRP (OR=1.54, CI; 1.12-2.18, p=0.008) were independent predictors of ACh induced CAS. However, there was no difference in clinical outcomes up to 12 months. Conclusion In conclusion, higher hs CRP was associated with higher incidence of CAS, worse angiographic characteristics and ischemic EKG change, but was not associated with clinical outcomes.

Angiographic and Clinical Characteristics according to Intracoronary Acetylcholine Dose in Patients with Myocardial Bridge

Objectives: It is well known that myocardial bridge (MB) is a risk factor of vasospastic angina. However, clinical and angiographic characteristics according to different acetylcholine (ACh) dose in patients with MB are not clarified yet. Methods: A total 483 consecutive patients who had angiographically proven MB underwent the intracoronary ACh provocation test. ACh was injected by incremental doses of 20, 50 and 100 μg into the left coronary artery. We evaluated the clinical and angiographic characteristics of patients with MB according to 3 different ACh doses. Results: The baseline clinical and procedural characteristics are well balanced among the three groups. The MB patients who responded to the lower ACh dose (20 μg) had higher incidence of baseline spasm, severe vasospasm and diffuse long spasms (>30 mm) than those who responded to the higher doses (50 and 100 μg). The incidence of 12-month mortality and recurrent chest pain was higher in the lower ACh dose group (20 μg). Conclusion: The patients with MB significantly reacting at the low ACh dose had more pronounced baseline spasm, severe and diffuse long coronary artery spasm, higher 12-month mortality and recurrent chest pain than those reacting with the higher ACh doses, suggesting that more intensive medical therapy will be required.

Successful Retrieval of a Fractured and Entrapped 0.035-Inch Terumo Wire in the Femoral Artery Using Biopsy Forceps

A 0.035-inch guide wire fracture and entrapment in a peripheral artery is a very rare complication, but when it does occur it may lead to life-threatening complications, such as perforation, thrombus formation, embolization, and subsequent limb ischemia. We describe our experience of successfully retrieving a fractured 0.035-inch Terumo guide wire in the external iliac artery using a biopsy forcep.

Impact of Heterogeneous Overlapping Drug-Eluting Stents on the Arterial Responses of Rabbit Iliac Arteries: A Comparison With Overlapping Bare Metal Stents

Background and Objectives Although the use of heterogeneous overlapping drug-eluting stents (DES) is not uncommon in clinical practice, whether the implantation sequences of heterogeneous DES will influence the endothelialization or arterial responses differently remains unclear. Materials and Methods Twenty-one rabbits were randomized to receive overlapping stents in the iliac artery for 3 months {distal sirolimus-eluting stent (SES, Cypher™)+proximal paclitaxel-eluting stent (PES, Taxus™) (C+T, n=7), distal Taxus+proximal Cypher (T+C, n=7) and bare metal stent (BMS)+BMS (B+B, n=7)}. Endothelial function was evaluated by the acetylcholine provocation test during follow-up angiography. Histopathological changes in proximal, overlapped, and distal stented segments were evaluated. Results Although the overall angiographic outcomes were comparable, late loss (mm) in the distal stented segment was higher in the B+B (0.39±0.07) and C+T (0.40±0.20) than that in the T+C (0.06±0.02) group (p<0.001). The incidence of acetylcholine-induced spasm was higher in the DES groups compared with BMS, regardless of the implantation sequences (85.7% in C+T vs. 14.3% in B+B vs. 71.4% in T+C, p=0.017). Notably, only the distal Cypher implantation group (C+T) had three cases of stent fracture. A histopathological analysis showed that despite similar arterial injury scores, Taxus and Cypher stents had higher inflammatory reactions at the overlapped and distal segments compared with those of BMS. Conclusion Despite similar arterial injury, higher inflammatory reactions were observed in overlapping DES segments regardless of the implantation sequence compared with that of BMS. Moreover, DES was associated with impaired endothelial function on the adjacent non-stented segments.

Aorta-right atrial tunnel: Is surgical correction mandatory?

An asymptomatic 31-year-old man with chronic hepatitis B and a 7-year history of lamivudine use was referred to our hospital for evaluation of a heart murmur. The patient had no family history of congenital heart disease or collagen vascular disease. Cardiac auscultation revealed a grade 3/6 continuous murmur at the right parasternal border. Transthoracic echocardiography revealed a round, tunnel-like structure from the left aortic sinus to the right atrium (RA; Figure 1A and 1B, arrows, and Movie IA and IB in the online-only Data Supplement) without any evidence of RA or right ventricular enlargement. Modified parasternal short-axis view (Figure 1C and Movie II in the online-only Data Supplement) of the aortic valve level demonstrated an anastomosis site to the RA with continuous turbulent flow on color Doppler examination. Continuous-wave Doppler obtained from the shunt indicated a high flow velocity with systolic and diastolic pattern at the anastomosis site to the RA (Figure 1D). Cardiac catheterization showed a normal pulmonary artery pressure (systolic/diastolic, 24/7 mm Hg) and normal mean RA pressure (4 mm Hg), and the Qp/Qs ratio was 1.3:1. Aortography confirmed a large tunnel beginning in the left aortic sinus and ending in the RA (Figure 2, asterisk, and Movie III in the online-only Data Supplement), with normal-looking left coronary arteries arising independently from different proximal portions of the tunnel. Importantly, no coronary myocardial branches originated from the tunnel, which is the …