[Show abstract][Hide abstract] ABSTRACT: There have been few randomized control trials comparing the incidence of stent fracture and primary patency among different self-expanding nitinol stents to date. The SMARTTM CONTROL stent (Cordis Corp, Miami Lakes, Florida, United States) has a peak-to-valley bridge and inline interconnection, whereas the COMPLETETM-SE stent (Medtronic Vascular, Santa Rosa, California, United States) crowns have been configured to minimize crown-to-crown interaction, increasing the stent's flexibility without compromising radial strength. Further, the 2011 ESC (European society of cardiology) guidelines recommend that dual antiplatelet therapy with aspirin and a thienopyridine such as clopidogrel should be administered for at least one month after infrainguinal bare metal stent implantation. Cilostazol has been reported to reduce intimal hyperplasia and subsequent repeat revascularization. To date, there has been no randomized study comparing the safety and efficacy of two different antiplatelet regimens, clopidogrel and cilostazol, following successful femoropopliteal stenting.
[Show abstract][Hide abstract] ABSTRACT: Angiographic and clinical outcomes remain relatively unfavorable for diabetic patients even after the use of drug-eluting stent. This prospective, multicenter, randomized study compared the relative efficacy and safety of resolute zotarolimus-eluting stent (R-ZES) and sirolimus-eluting stent (SES) implantation in diabetic patients with coronary artery disease. The primary end point was noninferiority of angiographic in-segment late loss at 9 months. Clinical events were also monitored for at least 12 months. Patient recruitment was prematurely stopped after enrollment of 256 patients (127 in R-ZES group and 129 in SES) because of discontinuing production of SES. The R-ZES was noninferior to the SES for 9-month in-segment late loss (0.34 ± 0.30 vs 0.39 ± 0.43 mm; difference -0.048; 95% confidence interval -0.157 to 0.061; upper 1-sided 95% confidence interval 0.044; p <0.001 for noninferiority). In addition, in-stent late loss (0.22 ± 0.29 vs 0.21 ± 0.40 mm, p = 0.849) and the rates of in-segment (1.2% vs 6.7%, p = 0.119) and in-stent (1.2% vs 3.3%, p = 0.621) binary restenoses were similar between the 2 groups. At 12 months, there were no statistical differences between the 2 groups in the incidence of any clinical outcomes (death, myocardial infarction, stent thrombosis, ischemia-driven target lesion revascularization, ischemia-driven target vessel revascularization, and composite outcomes). In conclusion, despite having reduced power because of early study termination, our study suggests that the R-ZES has noninferior angiographic outcomes at 9 months to the SES in diabetic patients with coronary artery disease.
The American journal of cardiology 09/2013; · 3.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: One of the major limitations of transradial coronary intervention is the inability to use large guiding system, which leads to the development of dedicated sheathless guide catheter system. However, these devices are not available in the Republic of Korea. We present a case in which conventional guiding catheter was used for sheathless transradial coronary intervention in the treatment of complex coronary anatomy.
[Show abstract][Hide abstract] ABSTRACT: Impaired exercise tolerance with dyspnea is common in hypertensive patients and this may be due to the exaggeration of nonuniform ventricular activation during exercise. So we want to evaluate the effect of left ventricular hypertrophy (LVH) on systolic intraventricular dyssynchrony during exercise.
A total of 85 patients with hypertension who having exertional dyspnea and 30 control individuals were enrolled. Exercise stress echocardiography was performed using a symptom limited, multistage supine bicycle test. To evaluate the dyssynchrony of left ventricular (LV), we calculated the standard deviation (SD) of the averaged time-to-peak systolic velocity (TPs-SD, ms) of 12 middle and basal LV segments obtained from the three standard apical views at rest and peak exercise.
There was no significant difference in systolic blood pressure (BP) and heart rate between the two groups. TPs-SD was significantly higher in patients with LVH at rest (31.5 ± 12.1 vs. 22.0 ± 12.6 ms, p = 0.002) with exaggeration of the degree at peak exercise (39.0 ± 11.9 vs. 24.6 ± 13.3 ms, p < 0.001). Multiple regression analysis showed LV mass index was independently associated with LV dyssynchrony at peak exercise (β = 0.515, p = 0.001) when controlled for age, sex, and systolic BP at peak exercise.
Intraventricular systolic dyssynchrony during exercise is significantly associated with the degree of LVH in hypertensive patients.
Journal of cardiovascular ultrasound 12/2012; 20(4):174-80.
[Show abstract][Hide abstract] ABSTRACT: The strength of each heart beat and the stiffness of large arteries contribute to blood pressure (BP). When the large arteries are stiff and their resistance greater, the afterload increases and this may change the function of the heart. However, the relation between common carotid artery stiffness and heart function in hypertensive patients has not been clarified.
Two hundred and twenty hypertensive patients underwent transthoracic and carotid echocardiography. Measurements of local arterial stiffness were taken at the right common carotid artery level and stiffness parameter (β), pressure-strain elasticity modulus and intima-media thickness were calculated. Brachial cuff BP was measured just before starting the carotid study. The patients with any cardiovascular disease, diabetes mellitus, stroke, transient ischemic attack, or carotid stenosis were excluded.
Carotid artery stiffness parameter (β) was correlated with age and left ventricular mass index (p < 0.005). Even though β was not correlated with LV systolic function, it was inversely correlated with diastolic function as measured by early mitral annular velocity. When the artery was stiffer, early mitral annular velocity (e') decreased (p < 0.001) and the index of left atrial (LA) pressure (early diastolic mitral inflow E velocity/e') increased (p = 0.001). In logistic regression, diastolic dysfunction was affected by age (beta -0.385, p = 0.001), LA volume index (beta 0.175, p = 0.013) and β (beta -0.273, p = 0.019).
In hypertensive patients, changes in carotid artery stiffness can affect the diastolic function, independent of age and LA volume index. Therefore, measurements and control of carotid stiffness can play an important role in the prevention of diastolic heart failure.
Journal of cardiovascular ultrasound 09/2012; 20(3):134-9.
[Show abstract][Hide abstract] ABSTRACT: Metabolic syndrome (MS) is associated with increased left ventricular (LV) mass and diastolic dysfunction. This study uses relatively load-independent Doppler tissue echocardiography to examine whether MS is associated with decreased longitudinal contractile reserve during dynamic exercise.
A total of 112 patients with relatively well-controlled, treated hypertension who complained of exertional dyspnea were enrolled (average age: 56.7 ± 10.5 years). Fifty-six were non-diabetic patients with MS (Group 1), and 56 were age-sex matched hypertensive patients without MS (Group 2). Exercise stress echo was performed using a symptom-limited, multistage, supine bicycle exercise test. Multiple Doppler parameters were obtained at baseline, at each stage of exercise, and during recovery.
There was no significant difference between the two groups in terms of age, gender, and hemodynamic variables. E/E', an index of LV filling pressure, was significantly higher in the MS group at rest and during exercise. The longitudinal contractile reserve, the change in S' (longitudinal tissue velocity) from baseline to peak exercise, was significantly lower in the MS group (2.00 ± 1.65 vs. 2.90 ± 1.66, p = 0.015). Multiple regression analysis showed independent association of MS with longitudinal contractile reserve when controlled for confounding factors, such as LV mass index, gender, blood pressure, and age (β = -0.235, p = 0.035).
Longitudinal contractile reserve was reduced in MS patients compared to others, although both groups demonstrated similar longitudinal contractile function at rest. We present the first demonstration that metabolic syndrome is independently associated with LV systolic dysfunction during exercise in hypertensive patients.
Journal of cardiovascular ultrasound 12/2011; 19(4):176-82.
[Show abstract][Hide abstract] ABSTRACT: A retrograde approach through collateral channels is thought to improve the success rate of percutaneous coronary intervention for chronic total coronary occlusion (CTO). Among CTO lesions, the in-stent chronic total reocclusion (ISR-CTO) is a subset with an unsatisfactory outcome despite repeated procedures. Various strategies and techniques are required to improve the success rate of this novel approach. We describe a case in which a long ISR-CTO was successfully recanalized by a drug-eluting balloon after antegrade ballooning of the proximal part of the lesion with retrograde wire crossing, and discuss the availability of this approach for the treatment of long ISR-CTO.
The Journal of invasive cardiology 07/2011; 23(7):E164-7. · 1.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Intravascular ultrasonography (IVUS) imaging is a user-friendly technique widely used during coronary interventions. An 80-year-old man was admitted with chest pain, and successful percutaneous coronary intervention was performed with stent implantation. One week later, the patient complained of further chest pain. Urgent coronary angiography showed total occlusion of the middle left anterior descending artery and the aspiration of thrombi was high. IVUS imaging showed inadequate stent strut apposition and distal dissection. We attempted another stent implantation but the IVUS catheter was stuck on the 0.014 inch wire. Therefore, we tried to pass the wire across the lateral side. After the wire was successfully passaged, the sprinter balloon was passed through the crushed stent to expand it. After 4 days later, the patient was discharged with no symptoms or electrocardiographic change.
[Show abstract][Hide abstract] ABSTRACT: Cardiovascular disease is the most common cause of death in patients undergoing dialysis. The accuracy of multidetector computed tomography (MDCT) for detecting coronary disease has not been determined, and little information is available regarding the performance of MDCT in patients undergoing dialysis.
Twenty-nine patients undergoing dialysis were analyzed and MDCT and coronary angiography (CAng) were performed consecutively. The coronary arteries were divided into four segments for analysis. We compared the significant stenosis lesions (≥50% luminal narrowing) identified by MDCT with those found by CAng. The total coronary artery calcium (CAC) score was determined by summing the individual lesion scores from each of the coronary branches.
One hundred and sixteen coronary artery branches in 29 patients were analyzed. The sensitivity, specificity, and positive and negative predictive values of MDCT for detecting significant coronary artery stenosis (≥50% stenosis) were 68%, 94%, 71% and 93%, respectively. The CAC scores were significantly higher in subjects with coronary artery disease (CAD) (514.0 ± 493.6 vs 254.3 ± 375.3, P = 0.05). The severe CAC score (>500) was related to the presence of significant CAD (P = 0.05) and the sensitivity and specificity for detecting significant CAD were 50% and 80%, respectively.
MDCT is a useful and non-invasive approach for detecting or excluding CAD in patients undergoing dialysis.
[Show abstract][Hide abstract] ABSTRACT: Few studies have compared the ability of sodium bicarbonate plus N-acetylcysteine (NAC) and sodium chloride plus NAC to prevent contrast-induced nephropathy (CIN) in diabetic patients with impaired renal function undergoing coronary or endovascular angiography or intervention. Diabetic patients (n = 382) with renal disease (serum creatinine ≥1.1 mg/dl and estimated glomerular filtration rate <60 ml/min/1.73 m(2)) were randomly assigned to receive prophylactic sodium chloride (saline group, n = 189) or sodium bicarbonate (bicarbonate group, n = 193) before elective coronary or endovascular angiography or intervention. All patients received oral NAC 1,200 mg 2 times/day for 2 days. The primary end point was CIN, defined as an increase in serum creatinine >25% or an absolute increase in serum creatinine ≥0.5 mg/dl within 48 hours after contrast exposure. There were no significant between-group differences in baseline characteristics. The primary end point was met in 10 patients (5.3%) in the saline group and 17 (9.0%) in the bicarbonate group (p = 0.17), with 2 (1.1%) and 4 (2.1%), respectively, requiring hemodialysis (p = 0.69). Rates of death, myocardial infarction, and stroke did not differ significantly at 1 month and 6 months after contrast exposure. In conclusion, hydration with sodium bicarbonate is not superior to hydration with sodium chloride in preventing CIN in patients with diabetic nephropathy undergoing coronary or endovascular angiography or intervention.
The American journal of cardiology 03/2011; 107(10):1447-52. · 3.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aims of this study were to investigate the long-term clinical outcomes of patients with successful versus unsuccessful revascularization with drug-eluting stents (DES) for chronic total occlusion (CTO).
The benefits of successful revascularization of CTO remain unclear.
Consecutive patients (n = 333) with "true" CTO, defined as Thrombolysis In Myocardial Infarction (TIMI) flow grade 0 on angiography and duration ≥3 months, were divided into two groups, those with successful (CTO success group, n = 251) and unsuccessful (CTO failure group, n = 82) revascularization with DES for CTO lesions. The primary endpoint was defined as major adverse cardiac events (MACE) the composite of death, Q-wave myocardial infarction (MI), or target vessel revascularization (TVR).
The CTO success group was significantly younger, with a higher involvement of LAD, and lower incidences of renal failure, previous myocardial infarction, and previous coronary intervention than the CTO failure group. After a median follow up of 1,317 days (interquartile range, 1,059-1,590 days), there were no significant between-group differences in rate of MACE, both after crude analysis (9.4% vs. 11.8%, log-rank P = 0.16) and after adjustment (HR 1.17; 95% CI 0.47-2.88, P = 0.53). On multivariate analysis, major predictors of MACE were left ventricle ejection fraction (LVEF) <40% (HR 3.14; 95% CI 1.39-7.09, P = 0.005) and multiple CTO (HR 2.38; 95% CI 1.01-5.71, P = 0.049).
Long-term clinical outcomes were similar in the CTO success and failure groups. Multiple CTOs and LVEF <40% in CTO patients were independent predictors of MACE.
Catheterization and Cardiovascular Interventions 03/2011; 78(3):346-53. · 2.51 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Arterial stiffness, assessed by aortic pulse wave velocity (PWV), has been reported to predict cardiovascular morbidity and mortality. We assessed the association between arterial stiffness, as determined by PWV, and occult coronary artery disease (CAD), as detected by multi-detector computed tomography (MDCT), in asymptomatic individuals.
We retrospectively enrolled 615 consecutive South Korean individuals who had undergone both brachial-ankle PWV (baPWV) and coronary CT angiography during general routine health evaluations at the Asan Medical Center in 2008.
We found that baPWV was positively correlated with age; body mass index; blood pressure; total cholesterol, homocysteine, and fasting blood glucose concentrations; and coronary artery calcium score. When we divided subjects into two groups according to the results of MDCT, we found that baPWV was significantly higher in subjects with (diameter of stenosis >50%) than without CAD (1573.2 ± 275.6 cm/s vs. 1409.6 ± 235.6 cm/s, p<0.01). The optimal baPWV cutoff value for detection of significant coronary arterial stenosis was 1426.0 cm/s, which had a sensitivity of 77% and a specificity of 63% (area under curve=0.71). After adjusting for age, smoking status, hypertension, diabetes, and dyslipidemia, the odds ratio for significant occult CAD was 3.30 (95% CI=1.47-7.41, p<0.01).
We found that baPWV was associated with risk factors for cardiovascular disease, including CACS, in asymptomatic individuals, and the optimal baPWV cutoff value for occult CAD detected by MDCT was 1426 cm/s. These findings suggest that baPWV may be a useful screening tool for predicting occult CAD.
International journal of cardiology 02/2011; 157(2):227-32. · 6.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We describe a 72-year-old man who presented with left hemiparesis due to acute cerebral infarction in the right fronto-temporal lobe. Three months prior to admission, he was hospitalized for right hemiparesis due to the acute cerebral infarction in the left anterior cerebral artery territory. To investigate the cause of his recurrent embolic event, a chest computed tomography scan and echocardiography were performed, which revealed advanced lung cancer invading contiguously through the pulmonary veins to the right main pulmonary artery and left atrium. Tumor embolism is a rare cause of stroke, occurring with primary or metastatic neoplasms of the lung. Echocardiography is a useful tool in patients with cerebral embolic episodes.
Journal of cardiovascular ultrasound 12/2010; 18(4):148-50.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the association between the length of the stented segment and the risk of stent thrombosis (ST) after drug-eluting stent (DES) implantation and to determine the cutoff value of stent length in higher risk of ST in routine clinical practice.
Despite the recommendations of full lesion coverage to prevent angiographic restenosis, the length of the stented segment has been a risk factor for DES-related ST.
A total of 3,145 consecutive patients (4,667 lesions) who underwent DES implantation were analyzed. The independent association of stent length with ST and its predictive value were evaluated for a median 29.6 months (interquartile range 21.6 to 37.5 months).
Stent thrombosis occurred in 68 patients (2.2%) at 3 years. The stent length/lesion was an independent predictor of ST (hazard ratio: 1.11, 95% confidence interval: 1.06 to 1.15, p < 0.001). The threshold of stent length for predicting ST was 31.5 mm (area under the receiver-operating characteristic curve: 0.746, 95% confidence interval: 0.699 to 0.793, p < 0.001), which had a sensitivity and specificity of 88.4% and 52.1%, respectively. Stent lengths >or=31.5 mm were associated with higher rates of ST (4.0% vs. 0.7%, p < 0.001), death (5.2% vs. 3.0%, p = 0.005), and myocardial infarction (2.4% vs. 0.7%, p = 0.001) at 3 years, as compared with stent lengths <31.5 mm.
Length of the stented segment was independently associated with the incidence of ST and death or myocardial infarction after DES implantation. The value of stent length >or=31.5 mm is a threshold for the prediction of ST.
[Show abstract][Hide abstract] ABSTRACT: Retrograde approach through collateral channels was recently proposed to increase the success rate of percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO), but this approach is still an incompletely described technique.
We analyzed 24 cases of retrograde PCI for CTO, which were done from July 2006 to April 2008.
Septal collaterals were more frequently used than epicardial collaterals (75% vs. 25%), without showing statistical differences in wire passage rate according to the size or location of the collaterals. Once the retrograde wire successfully crossed collateral (18/24 cases), CTO lesion was successfully crossed in all cases by using 4 different kinds of techniques: retrograde wire crossing (44%), kissing wire (22%), controlled antegrade and retrograde subintimal tracking (22%), and reverse controlled antegrade and retrograde subintimal tracking (11%). Among them, successful recanalization was achieved in 17 cases, yielding 71% retrograde PCI success rate. In failed cases with retrograde approach, 4 cases were recanalized by switching to antegrade approach. Thus, total PCI success rate was 88% (21/24 cases). There were several cases of unexpected complications mainly related to collateral-donor artery without in-hospital major adverse cardiac events (MACE). During clinical follow-up (median 10.3 months), overall MACE rate was 18% in the successful retrograde PCI group.
The retrograde approach can improve the success rate with PCI for CTO. However, strict case selection with systemized approach is essential due to the technical complexities accompanied by the potential risk of unexpected complications.
International journal of cardiology 06/2009; 144(2):219-29. · 6.18 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although intravascular ultrasound (IVUS) guidance has been useful in stenting for unprotected left main coronary artery stenosis, its impact on long-term mortality is still unclear.
In the MAIN-COMPARE registry, patients with unprotected left main coronary artery stenosis in a hemodynamically stable condition underwent elective stenting under the guidance of IVUS (756 patients) or conventional angiography (219 patients). Patients with acute myocardial infarction were excluded. The 3-year outcomes between the 2 groups were primarily compared using propensity-score matching in the entire and separate populations according to stent type. In 201 matched pairs of the overall population, there was a tendency of lower risk of 3-year morality with IVUS guidance compared with angiography guidance (6.0% versus 13.6%, log-rank P=0.063; hazard ratio, 0.54; 95% CI, 0.28 to 1.03; Cox-model P=0.061). In particular, in 145 matched pairs of patients receiving drug-eluting stent, the 3-year incidence of mortality was lower with IVUS guidance as compared with angiography guidance (4.7% versus 16.0%, log-rank P=0.048; hazard ratio, 0.39; 95% CI, 0.15 to 1.02; Cox model P=0.055). In contrast, the use of IVUS guidance did not reduce the risk of mortality in 47 matched pairs of patients receiving bare-metal stent (8.6% versus 10.8%, log-rank P=0.35; hazard ratio, 0.59; 95% CI, 0.18 to 1.91; Cox model P=0.38). The risk of myocardial infarction or target vessel revascularization was not associated with the use of IVUS guidance.
Elective stenting with IVUS guidance, especially in the placement of drug-eluting stent, may reduce the long-term mortality rate for unprotected left main coronary artery stenosis when compared with conventional angiography guidance.
[Show abstract][Hide abstract] ABSTRACT: A retrograde approach through the collateral channels is considered to improve the success rate of percutaneous coronary intervention for coronary chronic total occlusion (CTO). Various kinds of strategies and techniques are required to improve the success rate of this novel approach. We describe a case in which a CTO was successfully recanalized by the retrograde approach, using a new anchoring balloon technique (double anchoring balloon technique) which enabled the successful balloon passage through the hard CTO lesion.
Catheterization and Cardiovascular Interventions 05/2009; 73(6):791-4. · 2.51 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: An unusual type of hypertrophic cardiomyopathy was diagnosed in a 17-year-old girl who presented with dyspnea on exertion. The hypertrophied myocardium was localized to the anterior portion of the left ventricle from the base to the apex without left ventricular outflow tract obstruction. On cardiac magnetic resonance imaging (MRI), patchy and linear delayed hyperenhancement was shown in the anterior and inferior mid-wall, which is not concordant with the coronary artery territory.