A monounsaturated fatty acid (oleic acid) modulates electrical activity in atrial myocytes with calcium and sodium dysregulation

Background

Obesity and metabolic syndrome are important risk factors for atrial fibrillation. High plasma concentrations of monounsaturated fatty acids, including oleic acid (OLA), are frequently noted in obese individuals and patients with metabolic syndrome. However, it is not clear whether monounsaturated fatty acids (MUFAs) can directly modulate the electrophysiological characteristics of atrial myocytes.

Methods

Whole-cell patch clamp, indo-1 fluorescence, and Western blot analyses were used to record the action potentials (APs), ionic currents, and protein expressions of HL-1 myocytes incubated with and without (control) OLA (0.5 mM) for 24 h.

Results

Compared to control myocytes (n = 14), OLA-treated myocytes (n = 16) had shorter APD₉₀ (65 ± 6 vs. 85 ± 6 ms, p < 0.05) and APD₅₀ (24 ± 6 vs. 38 ± 4 ms, p < 0.05) with a higher incidence of delayed afterdepolarizations (35.7% vs. 7%, p < 0.05), which were suppressed by 4,4′-diisothiocyanatostilbene-2,2′-disulfonic acid (DIDS, a blocker of the calcium-activated chloride current). In addition, OLA-treated myocytes (n = 19) exhibited larger calcium transients (0.54 ± 0.06 vs. 0.38 ± 0.05 R410/485, p < 0.05), and sarcoplasmic reticular calcium contents (0.91 ± 0.05 vs. 0.64 ± 0.08 R410/485, p < 0.05) than control myocytes (n = 15). OLA-treated myocytes had larger late sodium currents, smaller sodium–calcium exchanger currents, and smaller sodium–potassium pump currents. Moreover OLA-treated myocytes had higher expressions of sarcoplasmic reticular Ca^2 +-ATPase and calmodulin kinase II, but lower expression of the sodium–potassium ATPase protein than control myocytes.

Conclusions

MUFAs can regulate atrial electrophysiological characteristics with calcium and sodium dysregulation, which may contribute to atrial arrhythmogenesis.     

Heart failure epicardial fat increases atrial arrhythmogenesis

Background

Obesity is an important risk factor for atrial fibrillation (AF) and heart failure (HF). The effects of epicardial fat on atrial electrophysiology were not clear. This study was to evaluate whether HF may modulate the effects of epicardial fat on atrial electrophysiology.

Methods

Conventional microelectrodes recording was used to record the action potential in left (LA) and right (RA) atria of healthy (control) rabbits before and after application of epicardial fat from control or HF (ventricular pacing of 360–400 bpm for 4 weeks) rabbits. Adipokine profiles were checked in epicardial fat of control and HF rabbits.

Results

The LA 90% of AP duration was prolonged by control epicardial fat (from 77 ± 6 to 87 ± 7 ms, p < 0.05, n = 7), and by HF epicardial fat (from 78 ± 3 to 98 ± 4 ms, p < 0.001, n = 9). However, control or HF epicardial fat did not change the AP morphology in RA. HF epicardial fat increased the contractility in LA (61 ± 11 vs. 35 ± 6 mg, p = 0.001), but not in RA. Control fat did not change the LA or RA contractility. Moreover, control and HF epicardial fat induced early and delayed afterdepolarizations in LA and RA, but only HF epicardial fat provoked spontaneous activity and burst firing in LA (n = 3/9, 33.3% vs. n = 0/7, 0%, n = 0/9, 0%, p < 0.05). Compared to control fat, HF epicardial fat, had lower resistin, C-reactive protein and serum amyloid A, but similar interluekin-6, leptin, monocyte chemotactic protein-1, adiponectin and adipsin.

Conclusions

HF epicardial fat increases atrial arrhythmogenesis, which may contribute to the higher atrial arrhythmia in obesity.     

Carbohydrate counting with an automated bolus calculator helps to improve glycaemic control in children with type 1 diabetes using multiple daily injection therapy: An 18-month observational study

Aims

This study aimed to investigate the effect of carbohydrate counting (carbC), with or without an automated bolus calculator (ABC), in children with type 1 diabetes treated with multiple daily insulin injections.

Methods

We evaluated 85 children, aged 9–16 years, with type 1 diabetes, divided into four groups: controls (n = 23), experienced carbC (n = 19), experienced carbC + ABC (n = 18) and non-experienced carbC + ABC (n = 25). Glycated haemoglobin (HbA1c), insulin use, and glycaemic variability – evaluated as high blood glucose index (HBGI) and low blood glucose index (LBGI) – were assessed at baseline and after 6 and 18 months.

Results

At baseline, age, disease duration, BMI, HbA1c, insulin use, and HBGI (but not LBGI; p = 0.020) were similar for all groups. After 6 months, HbA1c improved from baseline, although not significantly – patients using ABC (according to manufacturer's recommendations) HbA1c 7.14 ± 0.41% at 6 months vs. 7.35 ± 0.53% at baseline, (p = 0.136) or without carbC experience HbA1c 7.61 ± 0.62% vs. 7.95 ± 0.99% (p = 0.063). Patients using ABC had a better HBGI (p = 0.001) and a slightly worse LBGI (p = 0.010) than those not using ABC. ABC settings were then personalised. At 18 months, further improvements in HbA1c were seen in children using the ABC, especially in the non-experienced carbC group (−0.42% from baseline; p = 0.018).

Conclusions

CarbC helped to improve glycaemic control in children with type 1 diabetes using multiple daily injections. ABC use led to greater improvements in HbA1c, HBGI and LBGI compared with patients using only carbC, regardless of experience with carbC.     

Endothelial function and cardiovascular events in chronic kidney disease

Background

As patients with chronic kidney disease (CKD) are at high risk of developing coronary artery disease (CAD), it is important to stratify their cardiovascular risk. We investigated whether peripheral endothelial dysfunction is associated with the presence of CAD in patients with CKD and is a predictor of cardiovascular events.

Methods

We enrolled 383 CKD patients with at least one coronary risk factor. Peripheral endothelial function was assessed by reactive hyperemia peripheral arterial tonometry index (RHI). The presence of CAD was determined by coronary angiography. Cardiovascular events were assessed during follow-up.

Results

Ln-RHI was significantly lower in risk factor-matched CKD patients (n = 323) than risk factor-matched non-CKD patients (n = 323) (0.527 ± 0.192 vs. 0.580 ± 0.218, p = 0.001). In CKD patients (n = 383), Ln-RHI was significantly lower in CAD (0.499 ± 0.183, n = 262) than non-CAD (0.582 ± 0.206, n = 121) (p < 0.001) patients. Multivariate logistic regression analysis identified Ln-RHI as an independent factor associated with the presence of CAD (p = 0.001). During a mean follow-up period of 30 months, 90 cardiovascular events were recorded in CKD patients. Multivariate Cox hazard analysis identified low-Ln-RHI as an independent predictor of cardiovascular events (hazard ratio = 2.70, 95% confidence interval = 1.62–4.51, p < 0.001). The predictive value of combined Ln-RHI and Framingham risk score (FRS) was evaluated by net reclassification index (NRI) and C-statistics, which showed significant improvement (NRI = 22%, p < 0.001) (C-statistics: FRS = 0.49, FRS + Ln-RHI = 0.62, p = 0.005).

Conclusions

Endothelial function was significantly impaired in CKD patients and correlated with the presence of CAD. Severe endothelial dysfunction was an independent and incremental predictor of cardiovascular events in CKD.     

Blood flow characteristics in the ascending aorta after aortic valve replacement—a pilot study using 4D-flow MRI

Background

Aortic remodeling after aortic valve replacement (AVR) might be influenced by the postoperative blood flow pattern in the ascending aorta. This pilot study used flow-sensitive four-dimensional magnetic resonance imaging (4D-flow) to describe ascending aortic flow characteristics after various types of AVR.

Methods

4D-flow was acquired in 38 AVR patients (n = 9 mechanical, n = 8 stentless bioprosthesis, n = 14 stented bioprosthesis, n = 7 autograft) and 9 healthy controls. Analysis included grading of vortex and helix flow (0–3 point scale), assessment of systolic flow eccentricity (1–3 point scale), and quantification of the segmental distribution of peak systolic wall shear stress (WSS_peak) in the ascending aorta.

Results

Compared to controls, mechanical prostheses showed the most distinct vorticity (2.7 ± 0.5 vs. 0.7 ± 0.7; p < 0.001), while stented bioprostheses exhibited most distinct helicity (2.6 ± 0.7 vs. 1.6 ± 0.5; p = 0.002). Instead of a physiologic central flow, all stented, stentless and mechanical prostheses showed eccentric flow jets mainly directed towards the right-anterior aortic wall. Stented and stentless prostheses showed an asymmetric distribution of WSS_peak along the aortic circumference, with significantly increased local WSS_peak where the flow jet impinged on the aortic wall. Local WSS_peak was higher in stented (1.4 ± 0.7 N/m²) and stentless (1.3 ± 0.7 N/m²) compared to autografts (0.6 ± 0.2 N/m²; p = 0.005 and p = 0.008) and controls (0.7 ± 0.1 N/m²; p = 0.017 and p = 0.027). Autografts exhibited lower absolute WSS_peak than controls (0.4 ± 0.1 N/m² vs. 0.7 ± 0.2 N/m²; p = 0.003).

Conclusions

Flow characteristics in the ascending aorta after AVR are different from native aortic valves and differ between various types of AVR.     

Transient variations of transthoracic impedance as a predictor of heart failure and death in patients with implanted defibrillators

Background

Transient variations in physiological parameters may forewarn of life-threatening cardiac events, but are difficult to identify clinically. Implantable cardioverter defibrillators (ICD) designed to measure transthoracic impedance provide a surrogate marker for pulmonary congestion.

Objective

The aim of this study is to determine if the frequency of changes in transthoracic impedance (TTI) is associated with congestive heart failure (CHF) exacerbation and predicts mortality.

Methods

We followed 109 consecutive patients (pts) with ICDs (n = 58) or CRT-ICDs (n = 51) for a mean of 21.3 (+ 10.2) months. Using 80 ohm-days as a reference, we correlated the frequency of TTI changes above this index to CHF hospitalizations or death.

Results

There was at least one TTI threshold crossing in 79 (72%) pts over 23.3 months follow-up, with a mean of 1.8 ± 3.4 per year. There were 18 pts with CHF hospitalizations who had a mean of 4.3 TTI threshold crossings/year (S.D. = ± 7.3; median = 2.8), compared to 1.3 (S.D. = ± 1.5; median = 0.8) among pts without CHF hospitalizations (p = 0.0006). Among 20 patients who died during follow-up, there were 4.2 (S.D. = ± 7.0; median = 2.9) TTI threshold crossings/year, compared with 1.3 (S.D. = ± 1.3; median = 0.9) threshold crossings/year among survivors (p = 0.0004). Using Cox Proportional Hazard modeling, after adjusting for age, baseline EF, and number of shocks, TTI threshold crossing was an independent predictor of death (HR 1.72, 95% CI 1.26–2.36, p = 0.001).

Conclusions

Increased frequency of TTI threshold crossings may be a useful predictor of transient risk for identifying a subgroup of ICD recipients at greater individual risk for death or CHF hospitalizations.     

Effect of lifetime endurance training on left atrial mechanical function and on the risk of atrial fibrillation

Background

Left atrium (LA) dilation and P-wave duration are linked to the amount of endurance training and are risk factors for atrial fibrillation (AF). The aim of this study was to evaluate the impact of LA anatomical and electrical remodeling on its conduit and pump function measured by two-dimensional speckle tracking echocardiography (STE).

Method

Amateur male runners > 30 years were recruited. Study participants (n = 95) were stratified in 3 groups according to lifetime training hours: low (< 1500 h, n = 33), intermediate (1500 to 4500 h, n = 32) and high training group (> 4500 h, n = 30).

Results

No differences were found, between the groups, in terms of age, blood pressure, and diastolic function. LA maximal volume (30 ± 5, 33 ± 5 vs. 37 ± 6 ml/m², p < 0.001), and conduit volume index (9 ± 3, 11 ± 3 vs. 12 ± 3 ml/m², p < 0.001) increased significantly from the low to the high training group, unlike the STE parameters: pump strain − 15.0 ± 2.8, − 14.7 ± 2.7 vs. − 14.9 ± 2.6%, p = 0.927; conduit strain 23.3 ± 3.9, 22.1 ± 5.3 vs. 23.7 ± 5.7%, p = 0.455. Independent predictors of LA strain conduit function were age, maximal early diastolic velocity of the mitral annulus, heart rate and peak early diastolic filling velocity. The signal-averaged P-wave (135 ± 11, 139 ± 10 vs. 148 ± 14 ms, p < 0.001) increased from the low to the high training group. Four episodes of non-sustained AF were recorded in one runner of the high training group.

Conclusion

The LA anatomical and electrical remodeling does not have a negative impact on atrial mechanical function. Hence, a possible link between these risk factors for AF and its actual, rare occurrence in this athlete population, could not be uncovered in the present study.     

A combination of increased Rho kinase activity and N-terminal pro-B-type natriuretic peptide predicts worse cardiovascular outcome in patients with acute coronary syndrome

Background

Recent experimental evidence suggests that the Rho/Rho-kinase (ROCK) system may play an important role in the pathogenesis of acute coronary syndrome (ACS) but there are little clinical data. This study examined if ROCK activity is increased in patients with acute coronary syndrome and if ROCK activity predicts long‐term cardiovascular event.

Method

Blood samples were collected from 188 patients within 12 h after admission for ACS (53% men; aged 70 ± 13) and from 61 control subject. The main outcome measures were all cause mortality, readmission with ACS or congestive heart failure (CHF) from presentation within around 2 years (mean:14.4 ± 7.2 months; range: 0.5 to 26 months).

Results

ROCK activity increased in ST elevation myocardial infarction (STEMI, n = 90) (3.33 ± 0.93), non-STEMI (NSTEMI, n = 68) (3.37 ± 1.04) and unstable angina (UA, n = 30) (2.53 ± 0.59) groups when compared with disease controls (n = 31) (2.06 ± 0.38, all p < 0.001) and healthy controls (n = 30) (1.54 ± 0.43, all p < 0.001). There were 24 deaths, 34 readmissions with ACS and 15 admissions with CHF within 2 years. Patients with a high N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high ROCK activity on admission had a five-fold risk of a cardiovascular event (RR: 5.156; 95% CI: 2.180–12.191) when compared to those with low NT-proBNP and low ROCK activity.

Conclusion

ROCK activity was increased in patients with ACS, particularly in those with myocardial infarction. The combined usage of both ROCK activity and NT-proBNP might identify a subset of ACS patients at particularly high risk.     

Transapical mitral valved stent implantation: Enhanced survival and decreased paravalvular leakages

Background/Objectives

This study presents the recent results of transapical implantation of a new design of a mitral valved stent with up to three months follow-up.

Methods

A self-expanding re-designed mitral valved stent was implanted via transapical approach into the beating heart of eight pigs. Echocardiographic- and hemodynamic parameters were assessed before (n = 8), at 1 h (n = 8), at one month (n = 6), at two months (n = 2), and at three months (n = 1) after implantation and a cardiac CT was conducted.

Results

The stent was successfully deployed in all animals. Two animals died within the first month due to incorrect fixation force. Echocardiographic evaluation showed low gradients (3.9 ± 1.4 mm Hg and 1.9 ± 0.8 mm Hg across the valved stent and aortic valve) and a normal mitral annular plane systolic excursion (1.1 ± 0.2 cm) after one month. No paravalvular leakages (PVL) were detected after 1 h. The pulmonary artery pressure did not increase after valved stent implantation (p ≥ 0.106). The pulmonary capillary wedge pressure (PCWP) slightly increased to 16 ± 3 mm Hg after one month (p = 0.033). The left ventricular end-diastolic pressure was mildly elevated (15.8 ± 8.6 mm Hg) after one month.

Conclusions

Secure deployment and correct position of the valved stents were reproducibly achieved in the off-pump implantation procedure. No paravalvular leakages after 1 h as well as low gradients, few stent fractures and a normal longitudinal function after one month were achieved with this newly developed and well-aligned prototype. However, a number of challenges have been identified during this study and potential for improvement has been identified.     

High definition plus colonoscopy combined with i-scan tone enhancement vs. high definition colonoscopy for colorectal neoplasia: A randomized trial

Background

High definition endoscopy is the accepted standard in colonoscopy. However, an important problem is missed polyps.

Aims

Our objective was to assess the additional adenoma detection rate between high definition colonoscopy with tone enhancement (digital chromoendoscopy) vs. white light high definition colonoscopy.

Methods

In this prospective randomized trial patients were included to undergo a tandem colonoscopy. The first exam was a white light colonoscopy with removal of all visualized polyps. The second examination was randomly assigned in a 1:1 ratio as either again white light colonoscopy (Group A) or colonoscopy with tone enhancement (Group B). Primary endpoint was the adenoma detection rate during the second withdrawal (sample size calculation – 40 per group).

Results

67 lesions (Group A: n = 34 vs. Group B: n = 33) in 80 patients (mean age 61 years, male 64%) were identified on the first colonoscopy. The second colonoscopy detected 78 additional lesions: n = 60 with tone enhancement vs. n = 18 with white light endoscopy (p < 0.001). Tone enhancement found more additional adenomas (A n = 20 vs. B n = 6, p = 0.006) and identified significantly more missed adenomas per subject (0.5 vs. 0.15, p = 0.006).

Conclusions

High definition plus colonoscopy with tone enhancement detected more adenomas missed by white light colonoscopy.     

Clinical significance of fat infiltration in the moderator band and right ventricular myocardium in multislice CT,and its association with abnormal conduction seen in electrocardiogram

Purpose

We evaluated the clinical significance of fat infiltration in the moderator-band (MB) of the right ventricle (RV) and in the RV myocardium (RVM) and its association with conduction abnormalities in the electrocardiogram.

Materials and methods

132 subjects (58 male; age 59 ± 27 years) with no findings of organic-disease (all right and left side hearts were normal) undergoing electrocardiogram-gated non-contrast multislice-CT (Light-Speed-Ultra-16) were retrospectively analyzed for the presence of fat infiltrating the MB or RVM.

Results

MB fat infiltration was detected in 42 subjects, but these individuals showed no significant differences in the incidence of right bundle branch-block, mean QRS-width or standard-deviation of the QRS-axis, which would have suggested the presence of hemi left bundle branch-block. Only age (64.3 vs 57.9 years, p = 0.025) was significantly different in subjects with MB fat infiltration. But logistic regression showed none of the factor associated with increased presence of MB fat infiltration. RVM fat infiltration was detected in 35 subjects, again with no significant differences in the incidence of right bundle branch-block, QRS width or standard-deviation of the QRS axis. Only age (65.9 vs 57.8 years, p = 0.001) and gender (71% vs 51% female, p = 0.033) were significantly different in subjects with RVM fat infiltration. Logistic regression showed age (Odd-ratio = 1.05 and 95% CI = 1.01–1.08 p = 0.008) and female sex (Odd-ratio = 2.44 and 95% CI = 1.03–5.88; p = 0.043) were associated with increased RV fat infiltration.

Conclusions

MB or RVM fat infiltration seen on CT may not indicate organized abnormal myocardial conduction, but RVM fat infiltration may indicate only degeneration due to aging, especially in females.     

Optical coherence tomography analysis of strut coverage in biolimus- and sirolimus-eluting stents: 3-Month and 12-month serial follow-up

Background

No randomized studies have been conducted to investigate serial changes in optical coherence tomography (OCT) analyses following implantation of biolimus-A9-eluting stents (BES) and sirolimus-eluting stents (SES).

Methods

A total of 60 patients fulfilling the study criteria were randomly assigned into BES (n = 30) and SES (n = 30) implantation groups. Serial OCT evaluation at post-procedure, 3- and 12-month follow-up was performed in 46 patients [BES (n = 22) and SES (n = 24)]. OCT analyses were compared according to the type of stents and the follow-up time intervals. The percentage of uncovered struts was defined as the ratio of uncovered struts to total struts in all cross-sections. The primary endpoint was the percentage change (Δ) of uncovered struts in the 3- and 12-month follow-up samples.

Results

The percentage of uncovered struts at the 3-month time period was not significantly different in the BES and SES groups; the median value (interquartile range) was 14.7% (0.0–23.4) versus 8.6% (0.7–21.5) (p = 0.98), respectively. However, OCT at the 12-month follow-up showed a significantly lower percentage of uncovered struts [2.6% (0.8–5.6) versus 6.2% (1.7–14.7), (p = 0.028), respectively] without significant difference of neointimal thickness. BES showed a greater reduction of percentage Δ of uncovered struts from 3–12 months than that of SES [− 17.2 ± 14.5% versus − 7.7 ± 16.3%, respectively (p = 0.043)].

Conclusions

Both drug-eluting stents showed a high percentage of incomplete strut coverage at 3 months. However, BES showed a significantly lower percentage of uncovered struts at 12 months compared to that of SES. This was achieved by superior strut coverage from 3 to 12 months.     

20-Hour preprocedural hydration is not superior to 5-hour preprocedural hydration in the prevention of contrast-induced increases in serum creatinine and cystatin C

Background

Although intravenous hydration with isotonic saline is the standard therapy for the prevention of contrast-induced nephropathy (CIN), there is still insufficient evidence concerning the optimal timing to initiate preprocedural intravenous hydration with isotonic saline.

Methods

This study prospectively compared the contrast-induced increases in serum creatinine and cystatin C between 5-hour preprocedural intravenous hydration with isotonic saline (5 h-HS) and 20-hour preprocedural intravenous hydration with isotonic saline (20 h-HS) in 122 patients with renal insufficiency (estimated glomerular filtration rate of 15–60 ml/min/1.73 m²) undergoing an elective coronary procedure. The patients were randomly assigned to receive either 5 h-HS (n = 60) or 20 h-HS (n = 62). Serum creatinine and cystatin C were measured at baseline, immediately before contrast exposure, and 24 hours and 48 hours after contrast exposure. The primary end points were the maximal absolute and percent changes in serum creatinine and cystatin C from the baseline up to 48 hours after contrast exposure.

Results

The maximal absolute and percent changes in serum creatinine (0.01 ± 0.13 mg/dl vs. − 0.03 ± 0.16 mg/dl, p = 0.16; 0.87 ± 10.05% vs. − 1.50 ± 12.92%, p = 0.26; respectively) and cystatin C (− 0.05 ± 0.17 mg/l vs. − 0.06 ± 0.17 mg/l, p = 0.59; − 2.94 ± 9.29% vs. − 3.46 ± 9.21%, p = 0.75; respectively) did not differ between the 2 regimens.

Conclusions

20 h-HS is not superior to 5 h-HS in the prevention of the contrast-induced increases in serum creatinine and cystatin C in patients with renal insufficiency undergoing an elective coronary procedure.     

Longitudinal assessment of liver stiffness in patients undergoing antiviral treatment for hepatitis C

Background

Liver stiffness has been suggested as a parameter of fibrosis progression/regression in hepatitis C virus (HCV) patients.

Aim

To evaluate stiffness before and after peginterferon–ribavirin treatment.

Methods

Stiffness was prospectively measured in 74 HCV patients, 32 genotypes 1/4 (43.25%) and 42 genotypes 2/3 (56.75%), before, at end of treatment, and after 3 years of follow-up (49 patients). On the same study day, 21 patients underwent liver biopsy.

Results

In 55 patients with sustained virological response (74.32%), liver stiffness decreased significantly at end of therapy (6.8 ± 4.9 kPa) vs. baseline (9.5 ± 6.9 kPa, p = 0.04). The decrease vs. baseline was maintained in 30 sustained virological response patients after 3 years follow-up (6.8 ± 4.6 kPa vs. 10.8 ± 8.5 kPa, p = 0.0141). No difference was found at end of treatment vs. baseline (10.1 ± 4.7 kPa vs. 9.7 ± 4.2 kPa, p = 0.825) and after 3 years of follow-up vs. baseline (10.2 ± 3.4 kPa vs. 9.7 ± 4.2 kPa, p = 0.765) in null responders. Similar results were found in relapsers at end of treatment vs. baseline (13.7 ± 7.7 kPa vs. 15.2 ± 8.2 kPa, p = 0.74), and after 3 years of follow-up vs. baseline (16.9 ± 10.0 kPa vs. 15.2 ± 8.2 kPa, p = 0.734). Pre-treatment stiffness >12 kPa was significantly associated with no SVR (p < 0.025), RR = 2.44 (95% C.I. 1.17–5.07).

Conclusion

Liver stiffness may be useful to assess long-term antiviral treatment response.     

The effect of a diabetes education programme (PRIMAS) for people with type 1 diabetes: Results of a randomized trial

Objective

In a randomized, multi-centre trial, the efficacy of a self-management-oriented education programme (PRIMAS) for people with type 1 diabetes was compared with an established education programme as control group (CG). Primary outcome was the effect on glycaemic control in a 6-month follow-up. Secondary outcomes were the impact on emotional aspects, self-management related aspects and hypoglycaemia problems.

Methods

The study was conducted in an outpatient setting. 160 participants were randomized. Baseline characteristics in PRIMAS and CG were similar (age 45.1 ± 13.5 vs. 45.9 ± 13.1 years, p = .716; diabetes duration 18.8 ± 12.3 vs. 19.8 ± 13.4 years, p = .615; BMI 26.5 ± 4.6 vs. 27.5 ± 5.0 kg/m², p = .236; HbA1c 8.3 ± 1.1 vs. 8.1 ± 1.0%, p = .236).

Results

At follow-up there was a significant 0.4 percentage points greater reduction of HbA1c in PRIMAS compared to CG (Δ −0.4 ± 1.0% vs. Δ 0.0 ± 0.6%; p = .012). Also, diabetes-related distress (Δ −0.3 ± 0.7 vs. −0.1 ± 0.4, p = .032) and dissatisfaction with diabetes treatment (Δ −3.3 ± 6.9 vs. −1.9 ± 5.6, p = .024) decreased more in PRIMAS. Diabetes empowerment (Δ 2.6 ± 5.9 vs. 0.8 ± 5.1, p = .037) and diabetes self-efficacy (Δ 1.4 ± 3.6 vs. 0.2 ± 4.0, p = .013) increased in PRIMAS. Incidence of severe hypoglycemia, hypoglycemia awareness, diabetes knowledge, and self-care behaviour improved in both groups with no significant differences between groups.

Conclusion

PRIMAS is more effective in lowering HbA1c than a previously established education programmes and also showed superiority in reducing diabetes-related distress and increasing diabetes empowerment, diabetes self-efficacy and satisfaction with insulin therapy.     

Coronary artery calcium scoring: Influence of adaptive statistical iterative reconstruction using 64-MDCT

Objective

Assessment of coronary artery calcification is increasingly used for cardiovascular risk stratification. We evaluated the reliability of calcium-scoring results using a novel iterative reconstruction algorithm (ASIR) on a high-definition 64-slice CT scanner, as such data is lacking.

Methods and results

In 50 consecutive patients Agatston scores, calcium mass and volume score were assessed. Comparisons were performed between groups using filtered back projection (FBP) and 20–100% ASIR algorithms. Calcium score was measured in the coronary arteries, signal and noise were measured in the aortic root and left ventricle. In comparison with FBP, use of 20%, 40%, 60%, 80%, and 100% ASIR resulted in reduced image noise between groups (7.7%, 18.8%, 27.9%, 39.86%, and 48.56%, respectively; p < 0.001) without difference in signal (p = 0.60). With ASIR algorithms Agatston coronary calcium scoring significantly decreased compared with FBP algorithms (837.3 ± 130.3; 802.2 ± 124.9, 771.5 ± 120.7; 744.7 ± 116.8, 724.5 ± 114.2, and 709.2 ± 112.3 for 0%, 20%, 40%, 60%, 80%, and 100% ASIR, respectively, p < 0.001). Volumetric score decreased in a similar manner (p < 0.001) while calcium mass remained unchanged. Mean effective radiation dose was 0.81 ± 0.08 mSv.

Conclusion

ASIR results in image noise reduction. However, ASIR image reconstruction techniques for HDCT scans decrease Agatston coronary calcium scores. Thus, one needs to be aware of significant changes of the scoring results caused by different reconstruction methods.     

The heart rate response to adenosine: A simple predictor of adverse cardiac outcomes in asymptomatic patients with type 2 diabetes

Background

The Detection of Ischemia in Asymptomatic Diabetics (DIAD) study demonstrated a low 5-year hard cardiac event rate. We hypothesized that a blunted heart rate response (HRR, maximum percent change) to adenosine, a simple marker of cardiac autonomic neuropathy, will identify a cohort at higher cardiac risk.

Methods

In DIAD, 518 participants were randomized to screening adenosine myocardial perfusion imaging (MPI) and had available data. HRR < 20% was considered abnormal. The primary endpoint was a composite of nonfatal myocardial infarction and cardiac death.

Results

During 4.7 ± 0.9 years of follow-up 15 (3%) participants experienced the primary outcome. Participants with lower HRR experienced more events than those with higher HRR (8%, 3%, 1%, for HRR < 20% (n = 79), 20–39% (n = 182) and ≥ 40% (n = 257), respectively, p = 0.01). In a Cox proportional regression model that included MPI abnormalities and HRR, both were independently associated with cardiac events (p for model < 0.001). HRR < 20% was associated with 9-fold increased risk (p = 0.007) and moderate/large abnormal MPI was associated with 6-fold increased risk (p = 0.004). Participants with both abnormal MPI and HRR (n = 8) were at highest risk for cardiac events (38%) whereas those with HRR ≥ 40%, irrespective of MPI abnormalities (n = 234), were at extremely low risk (≤ 1%, log-rank p < 0.001).

Conclusions

In DIAD, abnormal HRR to adenosine infusion is an independent predictor of cardiac events. This easily obtained marker of cardiac autonomic neuropathy identifies asymptomatic patients with type 2 diabetes mellitus at increased risk, particularly when associated with abnormal MPI, who may warrant further testing and more aggressive cardiovascular risk factor management.     

Reduced flow-mediated vasodilation of brachial artery in children with primary snoring

Background

Sleep disordered breathing, especially obstructive sleep apnea, is associated with endothelial dysfunction in both adults and children. However, the role of primary snoring (PS) on endothelial function has not been investigated. This study aimed to examine flow-mediated vasodilation (FMD) in both normal weight and overweight children with PS.

Methods

Children aged 6–18 years with habitual snoring were recruited from our sleep disorder clinic. Non-snoring controls were recruited from participants of a community growth survey. All subjects underwent polysomnography and FMD evaluation on the same day. Children with body mass index of greater than the 85th percentile of the local reference were defined as overweight. Subjects were divided into groups of normal weight, overweight, non-snorers and PS for comparisons.

Results

Two hundred and one children, of whom 83 were overweight, with a mean ± SD age of 11.3 ± 2.7 years were recruited. Seventy three out of 201 children had PS. Both normal weight (7.9 ± 1.3 vs. 8.5 ± 0.9, p = 0.012) and overweight subjects (7.4 ± 1.4 vs. 8.1 ± 1.1, p = 0.006) with PS had significantly reduced FMD than the non-snoring controls. Multivariate linear regression model showed that PS was independently associated with reduced FMD in both normal weight (p = 0.014) and overweight subgroups (p = 0.016) after controlling for obstructive apnea hypopnea index.

Conclusions

PS in children is associated with reduced FMD, independent of obesity.     

Periodontal disease and systemic diseases in an older population

Objective

To evaluate the relationship between older adults’ medical and oral conditions and their self-reports of periodontal conditions with clinically obtained data.

Background

Concerns about oral health of elders and its association with systemic diseases have been gaining more attention.

Methods

A total of 201 older subjects were interviewed about their previous medical and dental histories and were asked to complete a health questionnaire. Each subject received full mouth exam, including counting number of natural teeth remaining, gingival (GI) and plaque index (PI), CPITN and denture status.

Results

Elders who completed health questionnaires had mean age of 62.5. Mean CPITN score was 1.62(±1.12), PI was 1.57(±1.48), and GI was 1.55(±1.31). Women had higher prevalence of CVD and osteoporosis than men (p = 0.008, p = 0.0001, respectively). Subjects who reported bleeding upon brushing had higher PI and GI scores (p = 0.03, p = 0.05, respectively). Smokers were more likely to describe their periodontal tissues as unhealthy (72.3% vs. 27.7%, p = 0.01), whereas self-reports of healthy vs. unhealthy gums did not differ between non-smokers.

Conclusion

These findings suggest that a number of systemic conditions are associated with indicators of periodontal disease, and self-reports of oral conditions are independent of systemic diseases.     

Coronary CT angiography with single-source and dual-source CT: Comparison of image quality and radiation dose between prospective ECG-triggered and retrospective ECG-gated protocols

Background

This study is conducted to investigate and compare image quality and radiation dose between prospective ECG-triggered and retrospective ECG-gated coronary CT angiography (CCTA) with the use of single-source CT (SSCT) and dual-source CT (DSCT).

Methods

A total of 209 patients who underwent CCTA with suspected coronary artery disease scanned with SSCT (n = 95) and DSCT (n = 114) scanners using prospective ECG-triggered and retrospective ECG-gated protocols were recruited from two institutions. The image was assessed by two experienced observers, while quantitative assessment was performed by measuring the image noise, the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR). Effective dose was calculated using the latest published conversion coefficient factor.

Results

A total of 2087 out of 2880 coronary artery segments were assessable, with 98.0% classified as of sufficient and 2.0% as of insufficient image quality for clinical diagnosis. There was no significant difference in overall image quality between prospective ECG-triggered and retrospective gated protocols, whether it was performed with DSCT or SSCT scanners. Prospective ECG-triggered protocol was compared in terms of radiation dose calculation between DSCT (6.5 ± 2.9 mSv) and SSCT (6.2 ± 1.0 mSv) scanners and no significant difference was noted (p = 0.99). However, the effective dose was significantly lower with DSCT (18.2 ± 8.3 mSv) than with SSCT (28.3 ± 7.0 mSv) in the retrospective gated protocol.

Conclusions

Prospective ECG-triggered CCTA reduces radiation dose significantly compared to retrospective ECG-gated CCTA, while maintaining good image quality.