Multimodality imaging assessment of the Biatrial remodeling of the burden of atrial high-rate episodes in patients with cardiac implanted electronic devices.

AIMS: The underlying mechanisms of atrial remodeling in cardiac implanted electronic device(CIED)-detected atrial high-rate episodes(AHRE) remains to be elucidated. METHODS: A cardiac computed tomography and a strain echocardiography were performed to delineate the structural and functional characteristics of both atria. Biatrial volumes, emptying fraction(EF) and peak atrial longitudinal/contractile strain(PALS/PACS) were evaluated. All AHRE were analyzed. RESULTS: A total of 80 CIED patients with AHRE were categorized by AHRE duration into 3 groups: Group 1: <6 min(n = 42), Group 2: 6 min âˆ¼ 6 h(n = 23), and Group 3: >6 h(n = 15). Left atrial(LA) maximal volume(Vmax), atrial precontraction volume(Vapc), minimal volume(Vmin), LAEF, and PALS/PACS were all increasingly worsened among the patients in the 3 groups (p value for trend <0.05). Compared to Group 1, Group 2 had decreased LA PALS/PACS. There was no significant difference in LA volume or EF between Group 1 and 2. Group 3 had enlarged biatrial volumes (LAVmax: 57.1(SD 16.0) vs. 45.4(SD 9.2) mL/m2, p = 0.002; LAVmin: 42.6(SD 18.2) vs. 28.2(SD 7.2) mL/m2, p < 0.001), impaired total LAEF (28.0(SD 13.7) vs. 38.2(SD 7.7)%, p = 0.004) and reduced PALS/PACS compared to Group 1. Atrial remodeling in those with AHRE >6 h had increased LA volumes, impaired LAEF and reduced PALS/PACS compared to those with AHRE <6 h. CONCLUSION: Functional remodeling of the atria manifested after AHRE >6 min. Increased biatrial volumes and decreased LA reservoir and pump function occurred when AHRE were > 6 h. These LA structural and functional may be considered surrogate imaging markers for stroke risk assessment in patients with CHA2DS2-VASc ≥2 and AHRE.

Distinct atrial remodeling in patients with subclinical atrial fibrillation: Lessons from computed tomographic images.

AIMS: Cardiac implanted electronic devices (CIEDs) can detect atrial high-rate episodes (AHREs) and challenge current management of subclinical atrial fibrillation (AF). METHODS: To characterize the anatomic and functional remodeling of cardiac structures between patients with subclinical AF (SCAF) and clinical AF. The predictors for AHREs ≥6 min were also investigated. RESULTS: We compared the atrial volume, dynamic function, and peri-atrial fat between 104 CIEDs (AHREs = 0, n = 12; SCAF, n = 66; CIEDs with AF, n = 26) and 40 paroxysmal AF patients who were planning for catheter ablation (AF for ablation) using 256-slice multidetector computed tomography for the duration of the AHREs. The maximal volume of the left atrium (LA) and LA appendage (LAA) were significantly smaller; the total emptying fraction (EF) and active EF of the LA and LAA were significantly better in the patients with SCAF than in those with clinical AF. Less peri-atrial fat (p < 0.001) and a greater LAA/ascending aorta (AA) Hounsfield unit (HU) ratio (p < 0.05) were noted in the patients with SCAF. Significantly increased volume reduced the total EF of LA and LAA and a reduced LAA/AA HU ratio (0.91 ± 0.18 vs 0.98 ± 0.03 vs 0.97 ± 0.05, p < 0.05) were demonstrated in patients with AHREs ≥6 min compared to those with AHREs <6 min and without AHRE. Multivariate analysis showed the reduced LAA/AA HU ratio is an independent predictor for the development of AHREs ≥6 min. CONCLUSION: As compared to clinical AF, patients with SCAF show a more favorable LA remodeling process. Among the patients with device-detected AHREs, worse LA remodeling and a reduced LAA/AA HU ratio were associated with the occurrence of AHREs ≥6 min. These findings may provide an incremental value for understanding SCAF.

Wave reflections, arterial stiffness, and orthostatic hypotension.

BACKGROUND: The effect of wave reflections on blood pressure change associated with posture remains unclear. We therefore applied a wave separation technique to investigate the relations of the backward pressure wave amplitude with orthostatic pressure changes and orthostatic hypotension (OH). METHODS: We analyzed data from 613 subjects who had participated in our hemodynamic studies. Measurements of brachial systolic (SBP) and diastolic blood pressures (DBP), carotid-femoral pulse wave velocity (cf-PWV), and backward pressure wave amplitude from a decomposed carotid pressure wave (Pb) were obtained at supine position. SBP and DBP were measured again 3 minutes after standing. OH was defined as a fall of ≥20 mm Hg in SBP and/or ≥10 mm Hg in DBP. RESULTS: Subjects with OH (n = 100) were characterized with significantly higher supine SBP and DBP and significantly lower standing SBP and DBP when compared with subjects without OH. Subjects with OH were also characterized with significantly higher cf-PWV and Pb. cf-PWV and Pb separately were significantly associated with the orthostatic SBP change in univariable and multivariable analyses. Also, cf-PWV and Pb separately were significant predictors of OH in univariable and multivariable analyses. cf-PWV predicted OH in the younger but less so in the older subgroup, whereas Pb demonstrated similar prediction in both subgroups. In a final multivariable model, both cf-PWV and Pb were significant independent predictors of OH. CONCLUSIONS: Wave reflections are an independent determinant of orthostatic SBP change and OH in both younger and older subjects.

Hip fracture and risk of acute myocardial infarction: a nationwide study.

Osteoporotic fractures are associated with increased mortality risk. However, little data are available on the risk of acute myocardial infarction (AMI) after hip fracture. Therefore, we investigated whether hip fracture increased the risk of AMI in a large, nationwide cohort study. We obtained data from 8758 patients diagnosed with hip fracture from 2000 to 2009 and from 4 matched controls for each patient from the Longitudinal Health Insurance Database (LHID 2000), Taiwan. Controls were matched for age, sex, comorbid disorders, and enrollment date. All subjects were followed up from the date of enrollment until AMI, death, or the end of data collection (2009). Cox's regression model adjusted for age, sex, comorbid disorders, and medication was used to assess independent factors determining the risk of development of AMI. As expected, despite the matching, the hip fracture patients had more risk factors for AMI at baseline. A total of 8758 subjects with hip fractures and 35,032 controls were identified. Among these patients, 1183 (257 hip fracture patients and 926 controls) developed AMI during the median 3.2-year (interquartile range 1.4 to 5.8 years) follow-up period. Patients with hip fractures had a higher incidence of AMI occurrence when compared with controls (8.7/1000 person-years versus 6.82/1000 person-years). Multivariate analysis adjusted for baseline covariates indicated that hip fracture was associated with a greater risk for AMI development (hazard ratio [HR] = 1.29; 95% confidence interval [CI] 1.12-1.48; p < 0.001). We conclude that hip fracture is independently associated with a higher risk of subsequent AMI.

The association of tooth scaling and decreased cardiovascular disease: a nationwide population-based study.

OBJECTIVE: Poor oral hygiene has been associated with an increased risk for cardiovascular disease. However, the association between preventive dentistry and cardiovascular risk reduction has remained undetermined. The aim of this study is to investigate the association between tooth scaling and the risk of cardiovascular events by using a nationwide, population-based study and a prospective cohort design. METHODS: Our analyses were conducted using information from a random sample of 1 million persons enrolled in the nationally representative Taiwan National Health Insurance Research Database. Exposed individuals consisted of all subjects who were aged ≥ 50 years and who received at least 1 tooth scaling in 2000. The comparison group of non-exposed persons consisted of persons who did not undergo tooth scaling and were matched to exposed individuals using propensity score matching by the time of enrollment, age, gender, history of coronary artery disease, diabetes, hypertension, and hyperlipidemia. RESULTS: During an average follow-up period of 7 years, 10,887 subjects who had ever received tooth scaling (exposed group) and 10,989 age-, gender-, and comorbidity-matched subjects who had not received tooth scaling (non-exposed group) were enrolled. The exposed group had a lower incidence of acute myocardial infarction (1.6% vs 2.2%, P<.001), stroke (8.9% vs 10%, P=.03), and total cardiovascular events (10% vs 11.6%, P<.001) when compared with the non-exposed group. After multivariate analysis, tooth scaling was an independent factor associated with less risk of developing future myocardial infarction (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.57-0.85), stroke (HR, 0.85; 95% CI, 0.78-0.93), and total cardiovascular events (HR, 0.84; 95% CI, 0.77-0.91). Furthermore, when compared with the non-exposed group, increasing frequency of tooth scaling correlated with a higher risk reduction of acute myocardial infarction, stroke, and total cardiovascular events (P for trend<.001). CONCLUSION: Tooth scaling was associated with a decreased risk for future cardiovascular events.

Decreased circulating endothelial progenitor cell levels and function in patients with nonalcoholic fatty liver disease.

OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is associated with advanced atherosclerosis and a higher risk of cardiovascular disease. Increasing evidence suggests that injured endothelial monolayer is regenerated by circulating bone marrow derived-endothelial progenitor cells (EPCs), and levels of circulating EPCs reflect vascular repair capacity. However, the relation between NAFLD and EPC remains unclear. Here, we tested the hypothesis that patients with nonalcoholic fatty liver disease (NAFLD) might have decreased endothelial progenitor cell (EPC) levels and attenuated EPC function. METHODS AND RESULTS: A total of 312 consecutive patients undergoing elective coronary angiography because of suspected coronary artery disease were screened and received examinations of abdominal ultrasonography between July 2009 and November 2010. Finally, 34 patients with an ultrasonographic diagnosis of NAFLD, and 68 age- and sex-matched controls without NAFLD were enrolled. Flow cytometry with quantification of EPC markers (defined as CD34(+), CD34(+)KDR(+), and CD34(+)KDR(+)CD133(+)) in peripheral blood samples was used to assess circulating EPC numbers. The adhesive function, and migration, and tube formation capacities of EPCs were also determined in NAFLD patients and controls. Patients with NAFLD had a significantly higher incidence of metabolic syndrome, previous myocardial infarction, hyperuricemia, and higher waist circumference, body mass index, fasting glucose and triglyceride levels. In addition, patients with NAFLD had significantly decreased circulating EPC levels (all P<0.05), attenuated EPC functions, and enhanced systemic inflammation compared to controls. Multivariate logistic regression analysis showed that circulating EPC level (CD34(+)KDR(+) [cells/10(5) events]) was an independent reverse predictor of NAFLD (Odds ratio: 0.78; 95% confidence interval: 0.69-0.89, P<0.001). CONCLUSIONS: NAFLD patients have decreased circulating EPC numbers and functions than those without NAFLD, which may be one of the mechanisms to explain atherosclerotic disease progression and enhanced cardiovascular risk in patients with NAFLD.