Impact of initial very low-level low-density lipoprotein cholesterol on the prognosis of acute myocardial infarction patients.

BACKGROUND: Cholesterol control with statins has been shown to have beneficial effects in coronary artery disease. However, the relationship between initial very low low-density lipoprotein (LDL) cholesterol levels and long-term clinical outcomes in patients with acute myocardial infarction (AMI) remains unclear. METHODS: A total of 8741 (mean age: 64.6 ± 12.7 years, men) consecutive AMI patients treated with drug-eluting stents were entered into the Korea Acute Myocardial Infarction Registry from November 2011 to December 2015. Patients were divided into six groups according to whether they were taking statins (on-statin group) or not (statin naive group) and depending on their LDL cholesterol level at admission (<70, 70-99, 100-129, 130-159, >160 mg/dl). Clinical outcomes at 24 months in patients with AMI were examined. RESULTS: The incidence of risk factors including hypertension, diabetes, coronary artery disease and heart failure was lower as LDL cholesterol increased, except in the on-statin group. Clinical outcomes, including total mortality at 24 months, showed better outcomes in those with high LDL cholesterol than those with low LDL cholesterol, except in the statin group. In the statin-naïve group, the higher the LDL cholesterol level, the higher the rate of 24-month survival. In a Cox regression model, initial low LDL cholesterol was an independent predictor of mortality at 24 months after adjusting for baseline confounding factors. CONCLUSIONS: At admission, a very low LDL cholesterol level (<70 mg/dL) in statin-naïve AMI patients undergoing percutaneous coronary intervention was independently associated with higher mortality at 24 months.

Impact of chronic outward force on arterial responses of proximal and distal of long superficial femoral artery stent.

BACKGROUND: Self-expanding nitinol stent (SENS) implantation is commonly oversized in the superficial femoral artery (SFA), and leads to chronic outward force (COF) and in-stent restenosis (ISR). This study aimed to investigate the impact of COF of oversizing SENS on ISR of SFA. METHODS: In patients with implanted SENS in SFA, intimal hyperplasia especially between proximal segment and distal segment was evaluated by quantitative angiography, and the impact of COF on mid-term angiographic outcomes was investigated. In addition, porcine model with implanted SENS was used to evaluate the impact of COF on angiographic and histopathologic outcomes at 1 month. Excised stented arteries were evaluated by histopathologic analysis. RESULTS: We analyzed 65 SENS in 61 patients with follow-up angiography at 6 months to 1 year. The baseline diameter was 6.8 ± 0.71 mm and length were 97.0 ± 33.8 mm for the SENS. The ratio of the diameter of the stent to the reference vessel was 1.3 ± 0.24 at the proximal portion and 1.53 ± 0.27 at the distal portion (P < 0.001). In the long SFA stent, stent-to-vessel ratio was significantly higher in the distal stent than in the proximal stent (1.3 ± 0.2 vs. 1.55 ± 0.25, P = 0.001). ISR incidence was higher at the distal stent (37.3% vs 52.6%, P = 0.029). All 11 pigs survived for 4 weeks after SENS implantation. The vessel diameter was 4.04 ± 0.40 mm (control group) vs 4.45 ± 0.63 mm (oversized group), and the implanted stent diameter was 5.27 ± 0.46 mm vs. 7.18 ± 0.4 mm (P = 0.001). The stent-to-vessel diameter ratio was 1.31 ± 0.12 versus 1.63 ± 0.20 (P < 0.001). After 4 weeks, restenosis % was 29.5 ± 12.9% versus 46.8 ± 21.5% (P = 0.016). The neointimal area was 5.37 ± 1.15 mm2 vs. 8.53 ± 5.18 mm2 (P = 0.05). The restenosis % was 39.34 ± 8.53% versus 63.97 ± 17.1% (P = 0.001). CONCLUSIONS: COF is an important cause of restenosis in the distal portion of the SFA stent. Optimal sizing of the SFA stent is important to reduce the incidence of restenosis. Therefore, COF was an important factor of restenosis following distal SFA stenting.

Assessment of Sex Differences in 5-Year Clinical Outcomes Following Endovascular Revascularization for Peripheral Artery Disease.

Percutaneous transluminal angioplasty (PTA) is an effective treatment strategy for peripheral artery disease (PAD). Data are limiting regarding sex differences in patients with PAD who underwent PTA. We assessed the sex-related differences on 5-year clinical outcomes in patients with PAD who underwent PTA. We prospectively evaluated 765 patients with PAD (596 males and 169 females) who underwent PTA. We performed propensity score matching (PSM) analysis to adjust for any potential confounders. The primary endpoints were 5-year major adverse cardiac and cerebrovascular events (MACE) and major adverse lower-limb events (MALE) assessed by Kaplan-Meier curved analysis and log rank test. After PSM analysis, baseline clinical characteristics were similar in male and female patients. There was a trend toward a higher rate of major hematoma in female patients (6.1% vs. 0.9%, p = 0.066) and a lower rate of below the ankle amputation (24.7% vs. 16.5%, p = 0.097). During the 5-year clinical follow-up, male and female patients had similar rates of MACE (14.9% vs. 15.8%, log rank p = 0.838) and MALE (34.8% vs. 28.2%, log rank p = 0.264) as well as the individual endpoints. In subgroup analysis adjusted by PSM, female patients had a higher risk of bleeding complications in age ≥ 65 years, hypertension, diabetes mellitus, chronic kidney disease, and in the non-critical limb ischemia patients. Of patients with preserved renal function, female patients had a higher risk of MALE as compared to males. In conclusion, female patients with PAD who underwent PTA showed similar 5-year MACE and MALE compared with male patients.

Impact of left ventricular hypertrophy on long-term clinical outcomes in hypertensive patients who underwent successful percutaneous coronary intervention with drug-eluting stents.

Left ventricular hypertrophy (LVH) is associated with increased risk for vascular events and mortality. This study investigated 8-year clinical outcomes of hypertensive patients with LVH who underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES) compared with hypertensive patients without LVH.A total of 1704 consecutive hypertensive patients who underwent PCI from 2004 to 2014 were enrolled. We classified them into either the LVH group (n = 406) or the control group (without LVH, n = 1298). LVH was defined by LV mass index > 115 g/m in men and > 95 g/m in women. After propensity score matched (PSM) analysis, 2 PSM groups (366 pairs, n = 732, c-statistic = 0.629) were generated.For up to 8 years, the LVH group showed a higher incidence of cardiac death (4.4% vs 1.2%, log-rank P = .023, hazard ratio: 3.371, 95% confidence interval: 1.109-10.25; P = .032) compared with the control group. However, there were no significant differences between the 2 groups in the incidence of total death, myocardial infarction, revascularization, and major adverse cardiac events up to 8 years.LVH in hypertensive patients who underwent successful PCI with DES was associated with higher incidence of cardiac death up to 8 years of follow-up. More careful managements and clinical follow-up are needed and treatment strategies should specifically focus to target prevention and reversal of LVH in hypertensive patients.

Impact of serum lipoprotein(a) on endothelium-dependent coronary vasomotor response assessed by intracoronary acetylcholine provocation.

BACKGROUND: Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic vascular disease. However, there are limited data regarding the impact of Lp(a) levels on the incidence and severity of endothelium-dependent coronary vasomotor response. PATIENTS AND METHODS: A total of 2416 patients without significant coronary artery lesion (<50% stenosis) by coronary angiography and underwent acetylcholine (ACh) provocation test were enrolled and categorized according to their serum Lp(a) level into four quartile groups: less than 6.70, 6.70-13.30, 13.30-26.27, and more than 26.27 mg/dl. The aim of this study is to estimate the incidence and severity of endothelium-dependent positive ACh provocation test in each group; moreover, to access the incidence of major adverse cardiovascular events, the composite of total death, myocardial infarction, and de novo percutaneous coronary intervention were compared between the four groups up to 5 years. RESULTS: The group with higher Lp(a) had a higher incidence of coronary heart disease, myocardial infarction, and peripheral arterial disease history. However, there was no difference among the four groups as regards the incidence of positive ACh provocation test, spasm severity, spasm extent, and location. However, at up to 5 years of clinical follow-up, the higher-Lp(a) group showed higher total death, de novo percutaneous coronary intervention, recurrent angina, and total major adverse cardiovascular events compared with the lower-Lp(a) groups. CONCLUSION: In our study, there was no relationship between the elevated Lp(a) level and the vasospastic response to the intracoronary ACh provocation test; however, higher Lp(a) levels were associated with poor clinical outcomes up to 5 years.

Five-Year Outcomes of Successful Percutaneous Coronary Intervention with Drug-Eluting Stents versus Medical Therapy for Chronic Total Occlusions.

PURPOSE: Many recent studies have reported that successful percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) for chronic total occlusion (CTO) has more beneficial effects than failed CTO-PCI; however, there are only limited data available from comparisons of successful CTO-PCI with medical therapy (MT) in the Korean population. MATERIALS AND METHODS: A total of 840 consecutive CTO patients who underwent diagnostic coronary angiography, receiving either PCI with DESs or MT, were enrolled. Patients were divided into two groups according to the treatment assigned. To adjust for potential confounders, propensity score matching (PSM) analysis was performed using logistic regression. Individual major clinical outcomes and major adverse cardiac events, a composite of total death, myocardial infarction (MI), stroke, and revascularization, were compared between the two groups up to 5 years. RESULTS: After PSM, two propensity-matched groups (265 pairs, n=530) were generated, and the baseline characteristics were balanced. Although the PCI group showed a higher incidence of target lesion and vessel revascularization on CTO, the incidence of MI tended to be lower [hazard ratio (HR): 0.339, 95% confidence interval (CI): 0.110 to 1.043, p=0.059] and the composite of total death or MI was lower (HR: 0.454, 95% CI: 0.224 to 0.919, p=0.028), compared with the MT group up to 5 years. CONCLUSION: In this study, successful CTO PCI with DESs was associated with a higher risk of repeat PCI for the target vessel, but showed a reduced incidence of death or MI.

Routine angiographic follow-up versus clinical follow-up in patients with diabetes following percutaneous coronary intervention with drug-eluting stents in Korean population.

AIMS: The usefulness of routine angiographic follow-up (RAF) and clinical follow-up (CF) after percutaneous coronary intervention (PCI) in patients with diabetes is not well understood. We compare 3-year clinical outcomes of RAF and CF in diabetic patients underwent PCI with drug-eluting stents (DES). METHODS: A total of 843 patients with diabetes who underwent PCI with DES were enrolled. RAF was performed at 6-9 months after PCI (n = 426). Rest of patients were medically managed and clinically followed (n = 417); symptom-driven events were captured. After propensity score matched analysis, 2 propensity-matched groups (262 pairs, n = 524, C-statistic = 0.750) were generated. The primary endpoint was major adverse cardiac events (MACE), the composite of total death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-target vessel revascularization (Non-TVR). RESULTS: During the 3-year follow-up period, the cumulative incidence of target lesion revascularization [TLR: hazard ratio (HR), 4.07; 95% confidence interval (CI), 1.18-9.34; p = 0.001], target vessel revascularization (TVR: HR, 4.02; 95% CI, 1.93-8.40; p < 0.001), non-TVR (HR, 4.92; 95% CI, 1.68-14.4; p = 0.004) and major adverse cardiac events (MACE: HR, 2.53; 95% CI, 1.60-4.01, p < 0.001) were significantly higher in the RAF group. However, the incidence of total death, non-fatal MI were similar between the two groups. CONCLUSIONS: RAF following index PCI with DES in patients with diabetes was associated with increased incidence of revascularization and MACE without changes of death or re-infarction rates and increased TLR and TVR rates in both first- and second-generation DES.

The association of chronic air pollutants with coronary artery spasm, vasospastic angina, and endothelial dysfunction.

BACKGROUND: We evaluated the effect of chronic exposure to air pollutants (APs) on coronary endothelial function and significant coronary artery spasm (CAS) as assessed by intracoronary acetylcholine (ACH) provocation test. PATIENTS AND METHODS: A total of 6430 patients with typical or atypical chest pain who underwent intracoronary ACH provocation test were enrolled. We obtained data on APs from the Korean National Institute of Environmental Research (http://www.nier.go.kr/). APs are largely divided into two types: particulate matter with aerodynamic diameter of less than or equal to 10 µm in size (PM10) and gaseous pollutants such as nitrogen dioxide, sulfur dioxide, carbon monoxide, and ozone. The primary endpoint is the incidence of significant CAS and its associated parameters during ACH provocation test. RESULTS: The incidence of CAS was positively correlated with an exposure duration of PM10, whereas nitrogen dioxide, sulfur dioxide, carbon monoxide, and ozone were shown to be unrelated to CAS. During the ACH provocation test, as PM10 increased, the frequency of CAS was increased, and the incidence of transient ST-segment elevation was also increased. There was a trend toward higher incidence of spontaneous spasm as PM10 increased. The mean exposure level of PM10 was 51.3±25.4 µg/m. The CAS risk increased by 4% when the level of PM10 increased by 20 µg/m by an adjusted Cox regression analysis. CONCLUSION: CAS incidence is closely related to exposure to PMs but not to gaseous pollutants. Particularly, higher exposure concentrations and longer exposure duration of PM10 increased the risk of CAS. These important findings provide a plausible mechanism that links air pollution to vasospastic angina and provide new insights into environmental factors.

Impact of diabetes mellitus on 5-year clinical outcomes in patients with chronic total occlusion lesions.

BACKGROUND: Diabetes mellitus (DM) is a major predictor of cardiovascular morbidity and mortality. However, there are limited data on the impact of DM in patients who have chronic total occlusion (CTO) lesion on long-term outcomes. PATIENTS AND METHODS: A total of 822 CTO patients who underwent coronary angiography, treated by either percutaneous coronary intervention or optimal medical therapy, were enrolled and divided into two groups: (i) diabetic group (n=363) and (ii) nondiabetic group (n=459). Individual and composite major clinical outcomes were compared up to 5 years. RESULTS: Propensity score matching analysis was carried out generating two groups (298 pairs, n=596, C-statistic=0.655) with balanced baseline characteristics. Up to 5 years, the DM group showed a higher trend toward revascularization (19.5 vs. 13.5%, P=0.051) and major adverse cardiovascular events (MACE) (24.7 vs. 19.1%, P=0.097) compared with the nondiabetic group. However, there was no difference in the incidence of death and myocardial infarction between the two groups. Subgroup analysis showed that the chronic kidney disease (CKD) subgroup was associated with a higher incidence of all-cause death, cardiac death, myocardial infarction, revascularization, and MACE in comparison with diabetic patients without CKD and nondiabetic patients, respectively (total MACE: 39 vs. 20.5 vs. 19.2% , P=0.001). Insulin-dependent diabetic patients had a significantly higher incidence of MACE (hazard ratio=1.58; 95% confidence interval: 1.04-2.40; P=0.03) compared with the nondiabetic patients. CONCLUSION: Diabetic patients with CTO were associated with a trend toward a higher incidence of revascularization and total MACE up to 5 years. Insulin-dependent and diabetic patients with CKD subgroups had a significantly higher incidence of total MACE.

Hyperuricaemia and development of type 2 diabetes mellitus in Asian population.

Recently, meta-analysis studies reported that hyperuricaemia is associated with higher incidence of type 2 diabetes mellitus (T2DM), however, there are limited data on the Asian population. The aim of this observational study is to estimate the long-term impact of hyperuricaemia on the new-onset T2DM and cardiovascular events. This study is based on a single-centre, all-comers, and large retrospective cohort. Subjects that visited from January 2004 to February 2014 were enrolled using the electronic database of Korea University Guro Hospital. A total of 10 505 patients without a history of T2DM were analyzed for uric acid, fasting glucose and haemoglobin (Hb) A1c level. Inclusion criteria included both Hb A1c <5.7% and fasting glucose level <100 mg/dL without T2DM. Hyperuricaemia was defined as a uric acid level ≥7.0 mg/dL in men, and ≥6.5 mg/dL in women. To adjust baseline confounders, a propensity score matching (PSM) analysis was performed. The impact of hyperuricaemia on the new-onset T2DM and cardiovascular events were compared with the non-hyperuricaemia during the 5-year clinical follow-up. After PSM, baseline characteristics of both groups were balanced. In a 5-year follow-up, the hyperuricaemia itself was a strong independent predictor of the incidence of new-onset T2DM (HR, 1.78; 95% CI, 1.12 to 2.8). Hyperuricaemia was a strong independent predictor of new-onset T2DM, which suggests a substantial implication for a correlation between uric acid concentration and insulin resistance (or insulin sensitivity). Also, hyperuricaemia is substantially implicated in cardiovascular risks and the further long-term cardiovascular events in the crude population, but it is not an independent predictor of long-term cardiovascular mortality in the matched population.

Selective ß1-Blockers Are Not Associated With New-onset Diabetes Mellitus in Hypertensive Patients.

BACKGROUND: Although ß-blockers are known to increase new-onset diabetes mellitus (DM), previous evidence have been controversial. It has been suggested that newer vasodilatory ß-blockers yield better glycemic control than older nonselective agents. The aim of this study was to evaluate the diabetogenicity of currently used newer ß-blockers based on ß1 receptor selectivity in a series of Asian population. METHODS: We investigated a total of 65,686 hypertensive patients without DM from 2004 to 2014. Patients with hemoglobin (Hb) A1c ≤6.0%, fasting blood glucose ≤110 mg/dL, and no history of diabetes or diabetic treatment were enrolled for analysis. Patients were divided into the ß-blockers group and non-ß-blockers group. Propensity score matching (PSM) analysis using a logistic regression model was performed to adjust for potential confounders. The primary end point was the cumulative incidence of new-onset DM, defined as a fasting blood glucose ≥126 mg/dL or HbA1c ≥6.5%, and major adverse cardiac and cerebral events (MACCE), defined as a composite of total death, nonfatal myocardial infarction, and cerebrovascular accidents. We investigated predictors of new-onset DM and MACCE based on 2 models, including clinical risk factors and co-medications, respectively. RESULTS: Mean follow-up duration was 30.91 ± 23.14 months in the entire group before adjustment. The ß-blockers group had a significantly higher incidence of new-onset DM and MACCE than the non-ß-blockers group. After PSM, analysis of a total of 2284 patients (1142 pairs, C-statistic = 0.752) showed no difference between the 2 groups in new-onset DM or MACCE. In multivariate analysis after PSM, baseline HbA1c, stroke, heart failure, nonselective ß-blockers, and age were independent predictors of new-onset DM. Selective ß1-blockers did not increase new-onset DM after adjustment for other antihypertensive medication and statins. CONCLUSIONS: In the era of newer ß-blockers, selective ß1-blockers were not associated with new-onset DM. More evidence is needed to verify this relationship and the underlying mechanisms.

Percutaneous Coronary Intervention Versus Optimal Medical Therapy for Chronic Total Coronary Occlusion With Well-Developed Collaterals.

BACKGROUND: The impact of percutaneous coronary intervention (PCI) on chronic total occlusion in patients with well-developed collaterals is not clear. METHODS AND RESULTS: A total of 640 chronic total occlusion patients with collateral flow grade ≥2 were divided into 2 groups; chronic total occlusion patients either treated with PCI (the PCI group; n=305) or optimal medical therapy (the optimal medical therapy group; n=335). To adjust for potential confounders, a propensity score matching analysis was performed. Major clinical outcomes were compared between the 2 groups up to 5 years. In the entire population, the PCI group had a lower hazard of myocardial infarction (hazard ratio [HR], 0.177; P=0.039; 95% confidence interval [CI], 0.03-0.91) and the composite of total death or myocardial infarction (HR, 0.298; P=0.017; 95% CI, 0.11-0.80); however, it showed higher hazard of target lesion revascularization (HR, 3.942; P=0.003; 95% CI, 1.58-9.81) and target vessel revascularization (HR, 4.218; P=0.001; 95% CI, 1.85-9.60). After propensity score matching, a total of 158 matched pairs were generated. Although the PCI group showed a higher hazard of target lesion revascularization (HR, 2.868; P=0.027; 95% CI, 1.13-7.31) and target vessel revascularization (HR=2.62; P=0.022; 95% CI, 1.15-5.97), it still exhibited a lower incidence of the composite of total death or myocardial infarction (HR, 0.263; P=0.017; 95% CI, 0.087-0.790). The mean ejection fraction was improved from 47.8% to 51.6% (P<0.001) after PCI. CONCLUSIONS: In our study, successful revascularization by PCI for chronic total occlusion lesions with well-developed collaterals was associated with lower incidence of death and myocardial infarction, improved left ventricular function, but increased repeat revascularization rate.

Clinical Value of Intraoperative Transit-Time Flow Measurement for Autogenous Radiocephalic Arteriovenous Fistula in Patients with Chronic Kidney Disease.

BACKGROUND: The intraoperative assessment of autogenous arteriovenous fistulas (AVF) is crucial for achieving an optimal surgical outcome; however, it is not easy to predict the adequacy of surgically created AVF. We used the transit-time flow measurement (TTFM) method to assess the anastomotic quality of AVF and to identify the cutoff value for predicting prognosis of established AVF. METHODS: Retrospective study, a total of 187 patients were included in this study. History of diabetes mellitus, hypertension, preoperative vein size, blood pressure, and other demographic data were collected. Surgery for creating radiocephalic AVF was performed by one surgeon, and intraoperative TTFM was performed. Flow parameters were recorded, including the maximal, mean, and minimal flow, and the pulsatility index (PI). Only mean flow ≤70 mL/min regarded as failure. We reviewed patients' follow-up, and we defined "successful AVF" when the patients who managed hemodialysis using established AVF without clinical problems during follow-up. RESULTS: All patients had a successful operation with adequate mean flow. The established mean flow from the radial artery to the cephalic vein was 199.8 ± 92.7 mL/min, and the PI was 0.57 ± 0.16. None of the patients had any complication during the immediate postoperative period, including infection. Mean follow-up period were 72.4 ± 42.7 weeks. Hemodialysis was maintained in 77.5% of the patients by using the established AVF, and the time to first hemodialysis with the established AVF after surgery was 61.0 ± 22.7 days. Correlation analysis revealed that the time to first hemodialysis was related with mean flow (P = 0.049) and PI (P = 0.009) and successful AVF was related only with PI (P = 0.028). According to curve fit and regression analysis, PI for 95% limit of successful AVF was from 0.43 to 0.77. CONCLUSIONS: Intraoperative TTFM is valuable for the assessment of the quality of established AVFs. Especially PI was correlated successful hemodialysis management for over 12 months, the recommended acceptable range was 0.43-0.77.

Surgical Removal of a Left Ventricular Thrombus Which Showed Morphologic Changes Over Time in a Patient with Stress-Induced Cardiomyopathy.

Although stress-induced cardiomyopathy (SCMP) is a reversible disease and the prognosis is usually excellent, several complications can occur and can result in fatal adverse events. The formation of left ventricular (LV) thrombus is one of these critical complications of SCMP. This report describes a case of SCMP complicated by formation of a LV thrombus that became increasingly mobile as LV contractility recovered, and for which surgical removal was performed. Here, we report a case of SCMP complicated by LV thrombus and review the literature regarding this topic.

A simple modification for a longer and larger internal thoracic artery as a composite Y-graft.

OBJECTIVES: Coronary artery bypass grafting (CABG) using bilateral internal thoracic artery (BITA) has been proven to improve survival. Many surgeons use the composite Y-graft which is made of left ITA (LITA) and right ITA (RITA) grafts. The LITA is typically anastomosed to left anterior descending artery (LAD). However, we have used RITA for LAD instead of LITA and reviewed the patency of ITA grafts and their clinical outcomes. METHODS: We analyzed 48 patients who underwent CABG using a BITA composite Y-graft from 2002 to 2012. In 30, LITA was anastomosed to LAD (Group L). The other 18 had RITA to LAD anastomosis (Group R). RESULTS: The mean age of Group R was higher than that of Group L (p = 0.009). Postoperative angiography was performed in 35 patients (73%). Two patients in Group L and none of the patients in Group R had an ITA graft failure. The incidence of ITA graft failure and new adverse cardiovascular events were not different between the two groups. CONCLUSION: The clinical outcome of RITA to LAD anastomosis is comparable with anastomosis of LITA to LAD in CABG using BITA composite Y-grafts. This technique may be useful when longer and larger ITA grafts are needed.