Fu-Chun Chiu

Association of low glomerular filtration rate and albuminuria with peripheral arterial disease: The National Health and Nutrition Examination Survey, 1999–2004

Microalbuminuria may be an early sign of intra-renal vascular dysfunction and a marker of vascular risk in the general population as well as in high-risk individuals. However, the association between albuminuria and PAD has been demonstrated only in few small studies. The aim of current study is to evaluate the relative impact of albuminuria and glomerular filtration rate on the risk of peripheral artery disease (PAD) in a nationally representative sample population. Data (ankle brachial index [ABI], urine albumin, fasting glucose, and glomerular filtration rate [GFR] estimated using the Modification of Diet in Renal Disease [MDRD] Study equation) were collected on 7068 adults from the National Health and Nutrition Examination Survey (NHANES 1999-2004). PAD was defined as ABI <0.9 or >1.4. There was a trend towards an association between the presence of abnormal renal function (GFR<60mL/min/1.73m(2)) and PAD in the non-diabetic patients (OR of 1.43, 95% CI: 0.98-2.09; P=0.07) where as the presence of abnormal renal function was strongly associated PAD in the diabetic patients (OR of 2.3, 95% CI: 1.34-3.95; P=0.046). On the contrary, albuminuria was independently associated with PAD in the non-diabetic (OR, 1.87; 95% CI, 1.38-2.52; P=0.0003) but not in the diabetic patients (OR: 1.08, 95% CI: 0.68-1.73, P=0.7411). We concluded that albuminuria, independent of renal function, is strongly associated with PAD in non-diabetic subjects. As diabetes develops and HbA1c level increases, the predictive value of albuminuria gradually diminishes after adjustment for renal function.

Measurement of Waist Circumference Midabdominal or iliac crest

OBJECTIVE Waist circumference (WC) is used to define central obesity. This study aimed to compare the performance of two recommended locations of WC measurement. RESEARCH DESIGN AND METHODS A cohort of 1,898 subjects who were without diabetes from 2006 to 2012 were followed for a median of 31 months (Taiwan Lifestyle Study). The WC-IC, recommended by the National Cholesterol Education Program Third Adult Treatment Panel, was measured at the superior border of the iliac crest, and the WC-mid, recommended by World Health Organization and International Diabetes Federation, was measured midway between the lowest ribs and the iliac crest. The abdominal subcutaneous fat area (SFA) and visceral fat area (VFA) were assessed by computed tomography. RESULTS There was greater difference between WC-IC and WC-mid measurements in women than in men (P < 0.001). Both WC-IC and WC-mid correlated significantly with BMI, VFA, and SFA (all P < 0.001). WC-mid was better correlated to VFA than WC-IC, particularly in women, and it correlated more strongly to blood pressure, plasma glucose, hemoglobin A1c, triglyceride levels, HDL cholesterol, and C-reactive protein (all P < 0.05). The association of WC-mid with hypertension, diabetes, and metabolic syndrome was slightly better than that of WC-IC (area under the receiver operator curve 0.7 vs. 0.69, 0.71 vs. 0.68, and 0.75 vs. 0.7, respectively; all age-adjusted P < 0.05). With 90 cm (male)/80 cm (female) as criteria for central obesity, WC-mid, but not WC-IC, predicted the incidence of diabetes development (age-adjusted P = 0.003). CONCLUSIONS WC-mid is a better measurement to define central obesity than WC-IC, particularly in women.

The Relationship Among Central Obesity, Systemic Inflammation, and Left Ventricular Diastolic Dysfunction as Determined by Structural Equation Modeling

The purpose of this study was to investigate the associations among central obesity, inflammation, and left ventricular (LV) diastolic dysfunction by structural equation modeling. Echocardiographic parameters were assessed in 102 otherwise‐healthy adults over age 30. The participants were classified as having LV diastolic dysfunction by echocardiographic findings including mitral inflow E/A ratio <1, deceleration time >220 cm/s, or decreased peak annular early diastolic velocity in tissue Doppler imaging or otherwise the control group. Serum C‐reactive protein (CRP) and lipid profile were also measured. The homeostasis model of insulin resistance (HOMA) was calculated. Central obesity was assessed by computerized tomography (CT) at the L4 level. In a multivariate regression analysis, the relationship between visceral adipose tissue (VAT) and LV diastolic dysfunction became insignificant when CRP was introduced into the model, although CRP itself was significantly associated with LV diastolic dysfunction (odds ratio (OR): 1.32, 95% confidence interval (CI): 1.01–1.72, P = 0.04). A significant correlation was also found between VAT and CRP (r = 0.70; P < 0.001). We then performed path analysis as illustrated by the structural equation model. This proved our hypotheses that VAT might affect LV diastolic dysfunction through the effect of CRP (total fat load with inflammation (B = 1.133, P < 0.001) and that inflammation might affect LV diastolic dysfunction (B = 0.373. P < 0.001)). Using structural equation modeling, we concluded that higher amounts of VAT were associated with low‐grade inflammation and this may lead to subclinical LV diastolic dysfunction in otherwise‐healthy subjects.

Coronary artery bypass graft surgery provides better survival in patients with acute coronary syndrome or ST-segment elevation myocardial infarction experiencing cardiogenic shock after percutaneous coronary intervention: A propensity score analysis

OBJECTIVE The objective of this study was to find the best treatment strategy in patients who had acute coronary syndrome and ST-segment elevation myocardial infarction sustaining cardiogenic shock. METHODS Patients having cardiogenic shock owing to acute coronary syndrome and ST-segment elevation myocardial infarction who required hemodynamic support with intra-aortic balloon counterpulsation were retrospectively retrieved from the clinical information system in a tertiary medical center in Taiwan. A propensity score-based matching process was applied to find equalized groups with documented involvement of more than 2 coronary vessels who received percutaneous coronary intervention only (PCI only group) and who underwent subsequent coronary artery bypass graft surgery after percutaneous coronary intervention (PCI+CABG group). A logistic regression model was used to find the factors associated with 30-day mortality. RESULTS The propensity analysis identified 44 patients in the PCI only group (35 men, 65 +/- 2 years, and 9 women, 75 +/- 4 years) and the other 44 patients in the PCI+CABG group (31 men, 67 +/- 2 years, and 13 women, 71 +/- 2 years) who had comparable baseline characteristics. The 30-day mortality, 40.9% in the PCI only group and 20.5% in the PCI+CABG group, was positively associated with percutaneous coronary intervention only (odds ratio, 3.33; 95% confidence intervals, 1.14-10.0; P = .03), increased age (odds ratio, 1.06 for each year; 95% confidence intervals, 1.01-1.12; P = .01) and a need to use extracorporeal membrane oxygenation (odds ratio, 9.64; 95% confidence intervals, 2.19-42.4; P < .001). CONCLUSIONS This study has shown the survival benefit of surgical intervention in high-risk patients with acute coronary syndrome or ST-segment elevation myocardial infarction who had cardiogenic shock after percutaneous coronary intervention.

Residual platelet reactivity after aspirin and clopidogrel treatment predicts 2-year major cardiovascular events in patients undergoing percutaneous coronary intervention

BACKGROUND Studies on the prognostic significance of residual platelet reactivity despite the use of dual anti-platelet agents are limited and seldom extend beyond 1year. METHODS This study enrolled 144 patients treated with standard-dose aspirin and clopidogrel and undergoing percutaneous coronary intervention (PCI). Platelet reactivity was measured by the Platelet Function Analyzer-100 (PFA-100) just before PCI and presented as collagen/epinephrine closure time (CEPI-CT) and collagen/adenosine diphosphate closure time (CADP-CT). Primary endpoint included cardiovascular death, myocardial infarction, and stroke. Secondary endpoint was the primary endpoint plus hospitalization due to unstable angina or urgent target vessel revascularization. RESULTS During the 24-month follow-up, 14 patients (9.7%) developed the primary endpoint events and 33 had the secondary endpoints. After controlling possible confounding factors, both CEPI-CT <193s and CADP-CT <95s were independently predictive of the primary endpoint (hazard ratio=3.5; 95% confidence interval: 1.04-11.7; p=0.044 and 5.3; 1.4-20.1; p=0.015, respectively). Only CADP-CT <95s remained significantly predictive of secondary endpoints in the follow-up periods of 0-9 and 9-24months, during which clopidogrel was mostly discontinued. CONCLUSION This study demonstrates that increased residual platelet reactivity measured by PFA-100 CADP-CT consistently predicts the occurrence of cardiovascular events following PCI throughout the 24-month follow-up period, irrespective of the changes in anti-platelet use.

Association of Albuminuria and Cancer Mortality

Background: The objective was to evaluate the association of albuminuria with cancer mortalities in adults ages 50 and older. Methods: A total of 6,112 adults ages 50 years and above without a history of cancer at baseline in the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994) were included in the analysis. Albuminuria was measured with urinary albumin-to-creatinine ratio (UACR) in mg/mmol. Cancer mortality was obtained from the NHANES III–linked follow-up database (up to December 31, 2006). Cox-regression models were used to examine the associations of interest. Results: Albuminuria was present in 705 men (17.5%) and 592 women (14.3%). During an average follow-up of 149 months, 613 subjects died of cancers including 184 lung cancers, 65 colorectal cancers, 55 prostate cancers, and 309 other cancers. There was an increased mortality risk associated with logarithmically transformed UACR for all-cancer [relative risk (RR), 1.20; 95% confidence interval (CI), 1.06-1.36], lung cancer (RR, 1.22; 95% CI, 1.05-1.43), and prostate cancer mortality (RR, 1.40; 95% CI, 1.01-1.95) in men. No associations between UACR and cancer were apparent in women. Conclusions: The analysis shows that albuminuria is associated with an increased risk of cancer death, specifically for all-cause, lung, and prostate cancers in men ages 50 and above. Impact: Further studies are needed to explore the relationship between albuminuria and specific cancers. Understanding the biological link between albuminuria and cancer will be critical for determining whether albuminuria represents an early marker or a potential therapeutic target. Cancer Epidemiol Biomarkers Prev; 19(11); 2950–7. ©2010 AACR.

Acute Effects of Biventricular Pacing in Heart Failure Patients with a Normal Ejection Fraction and Mechanical Dyssynchrony

Objectives: We tested the acute effects of resynchronization in heart failure patients with a normal (>50%) left ventricular (LV) ejection fraction (HFNEF) and mechanical dyssynchrony. Methods: Twenty-four HFNEF patients (72 ± 6 years, 5 male) with mechanical dyssynchrony (standard deviation of electromechanical time delay among 12 LV segments >35 ms) were studied with temporary pacing catheters in the right atrium, LV, and right ventricle (RV), and high-fidelity catheters for pressure recording. Using selected atrioventricular (AV) intervals of 60, 90, 120, 150, and 180 ms to optimize transmitral flow during simultaneous biventricular pacing, the RV-LV (VV) interval was then evaluated at RV30, RV15, 0, LV15, LV30, and LV45 (RV or LV indicates which ventricle was paced first, the number indicates by how many ms). Results: During simultaneous pacing, longer AV intervals were associated with improved LV pressure-derivative minimums and increased aortic pressures (p < 0.05 vs. normal sinus rhythm). In the VV interval from RV30 to LV45, there was a graded increase in the aortic velocity time integral and a decrease in dyssynchrony during simultaneous or LV-first pacing (p < 0.05 vs. normal sinus rhythm). Conclusions: For HFNEF patients with mechanical dyssynchrony, acute simultaneous biventricular or LV-first pacing with longer AV intervals reduced mechanical dyssynchrony and improved diastolic and systolic hemodynamics.

Impacts of Mitral E/e′ on Myocardial Contractile Motion and Synchronicity in Heart Failure Patients With Reduced Ejection Fraction: An Exercise–Echocardiography Study

The association between diastolic abnormality and postexercise contractile decompensation is uncertain in heart failure (HF) patients with reduced left ventricular ejection fraction (LVEF).

KCNN2 polymorphisms and cardiac tachyarrhythmias.

AbstractPotassium calcium-activated channel subfamily N member 2 (KCNN2) encodes an integral membrane protein that forms small-conductance calcium-activated potassium (SK) channels. Recent studies in animal models show that SK channels are important in atrial and ventricular repolarization and arrhythmogenesis. However, the importance of SK channels in human arrhythmia remains unclear. The purpose of the present study was to test the association between genetic polymorphism of the SK2 channel and the occurrence of cardiac tachyarrhythmias in humans. We enrolled 327 Han Chinese, including 72 with clinically significant ventricular tachyarrhythmias (VTa) who had a history of aborted sudden cardiac death (SCD) or unexplained syncope, 98 with a history of atrial fibrillation (AF), and 144 normal controls. We genotyped 12 representative tag single nucleotide polymorphisms (SNPs) across a 141-kb genetic region containing the KCNN2 gene; these captured the full haplotype information. The rs13184658 and rs10076582 variants of KCNN2 were associated with VTa in both the additive and dominant models (odds ratio [OR] 2.89, 95% confidence interval [CI] = 1.505–5.545, P = 0.001; and OR 2.55, 95% CI = 1.428–4.566, P = 0.002, respectively). After adjustment for potential risk factors, the association remained significant. The population attributable risks of these 2 variants of VTa were 17.3% and 10.6%, respectively. One variant (rs13184658) showed weak but significant association with AF in a dominant model (OR 1.91, CI = 1.025–3.570], P = 0.042). There was a significant association between the KCNN2 variants and clinically significant VTa. These findings suggest an association between KCNN2 and VTa; it also appears that KCNN2 variants may be adjunctive markers for risk stratification in patients susceptible to SCD.

B-001 ASSOCIATION OF HYPERTENSION WITH DIFFERENT FEATURES OF CORONARY ATHEROSCLEROSIS ASSESSED BY QUANTITATIVE CORONARY ANGIOGRAPHY AND MULTIDETECTOR COMPUTED TOMOGRAPHY

Subtitle Coronary atherosclerosis and hypertension. Background A plethora of evidence showing that there are certain distinctive morphological features of coronary atherosclerosis, includingthin-cap fibroatheroma, focal severe stenosis, superficial calcified nodules, diffuse non-stenotic plaques, and so forth. However, it is still not certain whether hypertension, a well-established coronary risk factor, is associated with all these different features. Methods This study included 224 consecutive patients underwent multidetector computed tomography before diagnostic coronary angiography. 5 atherosclerotic parameters, including severity score, extent score, calcium volume score, number of coronary arteries with ≥50% luminal stenosis, and number of plaques with ≥70% luminal stenosisof the entire coronary tree and individual coronary arteries were assessed. Hypertension was defined as patients being treated for hypertension or having a seated systolic blood pressure of ≥140 mm Hg or a diastolic blood pressure of ≥90 mm Hg. Results Among the 5 atherosclerotic parameters, hypertension was independently associated with the severity score (p = 0.026) and the extent score (p = 0.004) after adjustments for conventional risk factors, body-mass index, waist circumference, C-reactive protein, and intra-abdominal visceral fat area. Among the three coronary arteries, hypertension was significantly correlated with both the severity and extent scores of each individual coronary artery, except the severity score of the right coronary artery. However, systolic, diastolic, pulse pressure and heart rate measured at admission were not associated with all 5 parameters of coronary atherosclerosis. Conclusions Hypertension is more closely associated with less advanced and less vulnerable features of coronary atherosclerosis. This observation is consistent with the concept that hypertension is a risk factor for coronary atherosclerosis, rather than a trigger for myocardial infarction.