We all know A and B, but what about C? Exploring the management of modifiable risk factors in patients with atrial fibrillation

Background

The European Society of Cardiology (ESC) guidelines for the management of atrial fibrillation (AF) advise to treat AF according to the ABC pathway: A, anticoagulation, B, better symptom control, and C, comorbidities and cardiovascular risk factor management. Optimal treatment of comorbidities and risk factors slows AF progression and improves success rates of rhythm interventions for AF. However, several studies report underdiagnosis and therefore possible undertreatment for common cardiovascular comorbidities.

Purpose

This study aims to evaluate how common modifiable cardiovascular risk factors are managed in AF patients referred for catheter ablation.

Methods

This is a substudy of the ISOLATION study, a prospective cohort study including consecutive patients with paroxysmal or persistent AF referred for AF ablation. Screening for common modifiable risk factors for AF is structurally embedded in the work-up for AF ablation in the two participating centres. In the present study the prevalence of the following risk factors at this screening moment was assessed: (1) body mass index (BMI) above the target BMI for ablation (≥27 kg/m2), (2) hypertension, defined as on-site systolic blood pressure >130 mmHg and/or diastolic blood pressure >80 mmHg, (3) decreased glucose tolerance or diabetes mellitus, defined as HbA1c ≥6.5%, (4) dyslipidaemia, defined as low-density lipoprotein (LDL) ≥2.5 mmol/l, (5) regular alcohol consumption, defined as self-reported consumption of >15 standardized units/week, and (6) sleep disordered breathing (SDB), defined as apnoea-hypopnoea index (AHI) ≥15 assessed with home sleep tests (subset of patients).

Results

Among the 981 patients studied (median age 65 [59–71] years old, 64% male, 69% paroxysmal AF), previously diagnosed comorbidities were common (46% hypertension, 7% diabetes, 22% dyslipidaemia, 10% SDB), and a large proportion of patients received targeted treatment (Table 1). However, non-optimally managed risk factors remained significant (Figure 1). BMI ≥27 kg/m2 was present in 56% of patients. High systolic and diastolic blood pressure were present in 62% and 51% of patients, respectively, and any form of high blood pressure (either systolic or diastolic) was seen in 72% of patients. HbA1c was found to be above target ranges in 9% patients and LDL in 56%. A weekly alcohol consumption of ≥15 units was reported by 4% of patients. Screening for SDB was performed in a subset of patients (n=287), for whom AHI was ≥15 in 52%. Overall, 9% of patients had 4 or more non-optimally controlled modifiable risk factors, whereas the median number of modifiable risk factors was 2 [1–3].

Conclusions

Structural screening revealed a high prevalence of non-optimally controlled modifiable cardiovascular risk factors in patients referred for AF catheter ablation. According to recent ESC guidelines, improving treatment of comorbidities may improve AF ablation success rates and even reduce mortality.

Funding Acknowledgement

Type of funding sources: None.

The impact of a structured polygraphy screening incorporated in a novel remote mobile health pathway on sleep apnoea prevalence in patients with atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Untreated obstructive sleep apnoea (OSA) contributes to progression of atrial fibrillation (AF) and reduces the success rate of heart rhythm control strategies. OSA remains one of the most frequently underdiagnosed modifiable risk factors in AF patients due to a lack of standardized screening methods and low awareness.

Purpose

To assess the impact of implementation of a structured remote OSA screening and management pathway on the prevalence of OSA in AF patients scheduled for AF ablation procedures.

Methods

In October 2020, a novel remote OSA screening and management pathway (VIRTUAL-SAFARI) was introduced in two AF outpatient clinics in the Netherlands. Consecutive patients scheduled for AF ablation were offered OSA screening consisting of sending a portable home sleep test to patients’ homes to perform a remote sleep recording for one night, analysis by a sleep physician, discussion of results with the patient, and initiation of treatment (when applicable). The impact of this structural screening strategy was assessed by comparing the prevalence of concomitant OSA (defined as apnoea-hypopnoea index ≥5) for patients scheduled for AF ablation in the year before and after introduction of the OSA management pathway.

Results

A total of 733 patients was studied, 308 in the year before (Oct ’19 - Sep ’20) and 425 in the year after (Oct ’20 - Sep ’21) introduction of the VIRTUAL-SAFARI pathway. Median age was 65 [58-71], 64% was male and median body mass index (BMI) was 27 [25-30] kg/m2. Baseline characteristics were comparable for the groups before and after introduction of the pathway (Table 1).

In the cohort before pathway introduction, OSA had been diagnosed in 26 patients (8%, Figure 1) and was treated with positive airway pressure in 10 cases (3%).

In the cohort after pathway introduction, OSA had previously been diagnosed in 53 patients (12%). Eighty-eight percent of patients without previous OSA screening was referred via the remote pathway. Results of the sleep recordings were available for 213 (59%) at the time of this analysis. Previously unknown OSA was diagnosed in 184 patients (86% of available recordings), increasing the prevalence of confirmed OSA to 237 (55%). For 22% of patients, results of sleep recordings are pending. Absence of OSA was confirmed in 9%, and 13% of patients had not been screened (e.g. because of patient preference or logistical reasons). After pathway introduction, 82 patients (19%) were treated or received advice to start treatment with positive airway pressure. Treatment decisions are pending for 9% of the cohort.

Conclusion

After the implementation of structured remote OSA screening in a well characterized cohort of consecutive patients scheduled for AF ablation, the prevalence of diagnosed OSA increased from 8% to 55%. Whether appropriate risk factor management, including treatment of OSA identified by structured screening, will improve AF outcomes needs to be tested in future studies.

Optimization of a care pathway before atrial fibrillation ablation with the integration of translational research into routine clinical care

Funding Acknowledgements

Type of funding sources: None.

Background

The diagnostic work-up for atrial fibrillation (AF) catheter ablation is often complex and expensive. Improving the organization of this work-up may help to streamline patient journeys and to reduce administrative burden and costs. Additionally, reorganizing the existing work-up provides the opportunity to integrate (translational) research into routine clinical care, hereby contributing to improved patient selection and improved care for future patients.

Purpose

The aim of this project was to optimize a care pathway for patients considered for AF ablation, with the goals to improve the patient journey and simultaneously integrate research into the clinical process.

Methods

The Lean Six Sigma approach was used to map the pre-existing process, identify constraints in the process and formulate countermeasures. The impact of this pathway optimization was evaluated using four outcome measures: (1) efficient use of medical resources, defined as the percentage of patients receiving the pre-ablation work-up and eventually undergoing AF ablation, (2) number of hospital visits and consultations with a cardiologist, (3) pathway compliance, defined as the percentage of patients that completed the work-up with a maximum of 2 outpatient hospital visits, a maximum of 1 cardiologist consultation, laboratory results available, and a complete echocardiogram available, and (4) completeness of scientific data, defined as the availability of a predefined set of relevant variables (clinical indicators, medication, laboratory results and echocardiography derived data).

Results

Five root causes for constraints in the pre-existing work-up were identified and corresponding countermeasures were formulated (Figure 1). The impact of the countermeasures was studied for 33 patients before and 26 patients after pathway optimization. After optimization, efficient use of resources increased from 44% to 95% (p<0.01). The project resulted in fewer hospital visits per patient (3.2 ±1.2 versus 2.3 ±0.8, p=0.01) and fewer cardiologist consultations (1.8 ±0.7 versus 1.0 ±0.3, p<0.01). Pathway compliance increased significantly (3% versus 73%, p<0.01), an increase that was reflected in all separate components of overall pathway compliance (Figure 2, panel A). The percentage of available data for scientific research increased from 80% to 94% (p<0.01), resulting in a complete dataset in 73% of patients after, compared to only 15% of patients prior to the optimization project (p<0.01, Figure 2, panel B).

Conclusions

This optimization project resulted in a more efficient care pathway for patients considered for AF ablation. The structural integration of research into the care pathway may lay the foundations for further improvements of AF care in the future.

Endocardial pacing results in better electrical resynchronization and hemodynamic improvement than epicardial pacing in CRT

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The original study was financially supported by Medtronic (Minneapolis, Minnesota). The investigation of the current abstract is unrelated to the original financial support.

Background

Cardiac resynchronization therapy (CRT) is conventionally applied by means of a transvenous epicardial left ventricular (LV) lead. Studies suggest that endocardial LV pacing may result in better resynchronization and LV function than epicardial LV pacing.

Purpose

To investigate whether endocardial pacing results in better electrical resynchronization and hemodynamic improvement compared to epicardial pacing.

Methods

Patients with an indication for CRT were prospectively included from two hospitals. In all patients, LV pacing was performed endocardially and epicardially in the postero-lateral region. QRS area was calculated from vectorcardiograms that were synthesized from 12-lead ECGs. Acute hemodynamic improvement was assessed as the change in maximum rate of rise of LV-pressure (%ΔLVdP/dtmax). We assessed the effects of endocardial and epicardial LV pacing on the change in QRS area (∆QRS area) and LVdP/dtmax (%ΔLVdP/dtmax).

Results

A total of 16 patients (age 66 ± 11 years, 56% male, 31% ischemic cardiomyopathy, QRS duration 166±18ms, LBBB in 88%) were included. Endocardial pacing resulted in greater ∆QRS area than epicardial pacing (-51 ± 34 µVs vs. -24 ± 37 µVs, p = 0.021, Panel A). In addition, endocardial pacing led to a larger %ΔLVdP/dtmax as compared to epicardial pacing (21 ± 12% vs. 18 ± 9%, p = 0.025, Panel B).

Conclusion

Compared to conventional epicardial LV pacing in CRT, endocardial LV pacing results in better electrical resynchronization and acute hemodynamic improvement.

Prospective evaluation of the learning curve and electrical characteristics of left bundle branch area pacing

Background

Left bundle branch area pacing (LBBAP) has recently been introduced as a physiological pacing technique with a synchronous ventricular activation.

Objective

To prospectively evaluate the feasibility and learning curve, as well as the electrical characteristics of LBBAP.

Methods

In 80 consecutive LBBAP pacemaker patients, ECG characteristics during intrinsic rhythm, RV septum pacing (RVSP) and LBBAP were evaluated. From the ECG's QRS duration and LVAT (stimulus to V6 R-wave peak time, RWPT) were measured. Also, the left bundle branch potential (LBBpot) to V6 RWPT interval was measured and compared to the LVAT. After conversion of the ECG into VCG (Kors conversion matrix), QRS area, as measurement for electrical dyssynchrony, was calculated.

Results

Permanent lead implantation was successful in 77/80 patients (96%) undergoing an attempt at LBBAP. LBBAP lead implantation time as well as fluoroscopy time were significantly shorter during last 25% of implantation compared to first 25% of implantations (17±5 min vs. 33±16 min and 12±7 min vs. 21±13 min, respectively, panel A and B). LBB capture was obtained in 54/80 patients (68%). In 36/45 patients (80%) with intact AV conduction and narrow QRS an LBBpot was present. The mean interval between the LBBpot and the onset of QRS was 22±6 ms.

In the patients with narrow QRS (n=45), QRS duration increased significantly during both RVSP (139±24 ms) and LBBAP (123±21 ms), compared to intrinsic rhythm (95±13 ms).

QRS area on the other hand, increased during both RVSP (73±20 μVs) but decreased during LBBAP (41±15 μVs), to values close to intrinsic rhythm (32±16 μVs, panel C). For all patients, QRS area was significantly lower in patients with LBB capture compared to patients without capture (43±18 μVs vs 54±21 μVs, respectively).

In patients with LBB capture (n=54), LVAT was significantly shorter compared to patients without LBB capture (75±14 vs. 88±9 ms, respectively). In the patients with LBB capture, there was a significant correlation between the LBBpot – V6 RWPT and S – V6 RWPT intervals (Pearson correlation 0.739, P<0.001).

Conclusion

LBBAP is a safe and feasible technique, with a clear learning curve that seems obtained after ± 40–60 implantations. LBB capture is obtained in two-thirds of patients. Although QRS duration remains prolonged, LBBAP largely restores ventricular electrical synchrony to values close to intrinsic (narrow QRS) rhythm.

Funding Acknowledgement

Type of funding sources: None.

Comparison of QRSarea and left ventricular activation time during left bundle branch pacing and left ventricular septal pacing

Funding Acknowledgements

Type of funding sources: None.

Background

Left bundle branch area pacing (LBBAP) has recently been introduced as a novel physiological pacing strategy. Within LBBAP, distinction is made between left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP, no left bundle capture).

Objective

To compare acute electrocardiographic (ECG) and vectorcardiographic (VCG) effects of LBBP and LVSP as compared to intrinsic conduction.

Methods

In 50 patients with normal cardiac function and pacemaker indication for bradycardia, ECG characteristics of LBBP and LVSP were evaluated during RVSP and pacing at various depths in the septum: starting at the RV side of the septum: the last position with QS morphology, the first position with r’ morphology, LVSP and – in patients where LBB capture was achieved – LBBP. From the ECG’s QRS duration and QRS morphology in V1, and the stimulus-LVAT interval were measured. After conversion of the ECG into VCG (Kors conversion matrix), QRS area was calculated.

Results

In LVSP, QRS area significantly decreased from 82 ± 29 µVs during RVSP to 46 ± 12 µVs during LVSP. In patients where LBB capture was achieved QRS area significantly decreased from 78 ± 23 µVs to 38 ± 15 µVs in LBBP. In patients with LBB capture, QRS area was significantly smaller during LBBP compared to LVSP (figure A), but LVAT was not significantly different (figure B, p = 0.138).

In patients with normal ventricular activation where LBBP was achieved (n = 20), QRS area was significantly larger during LVSP (48 ± 17) compared to LBBP (37 ± 16), the latter being not significantly different from normal intrinsic ventricular activation (35 ± 19 µVs).

Conclusions

ECG and VCG indices demonstrate that ventricular dyssynchrony is comparable but slightly more synchronous during LBBP compared to LVSP. Abstract Figure. QRS area and S-LVAT in LVSP and LBBP

Reduction in QRS area correlates with hemodynamic response during CRT-device implantation

Funding Acknowledgements

Type of funding sources: None.

Background Previous studies have shown that reduction in QRS area after cardiac resynchronization therapy (CRT) is associated with improved long-term clinical outcome.

Purpose To investigate whether reduction in QRS area is associated with hemodynamic improvement and whether QRS area reduction could be used for CRT optimization, with respect to LV lead position and device programming in individual patients.

Methods A total of 78 patients with indication for CRT were prospectively included in 4 hospitals. QRS area was calculated from vectorcardiograms that were synthesized from 12-lead ECG’s. Acute hemodynamic response was assessed invasively as the maximum rate of percentual left ventricular (LV) pressure (%LVdP/dtmax) rise.  QRS area reduction was studied in relation to LV-lead position (n = 26), proximal versus distal LV lead position (n = 27), and VV-delay (n = 25).

Results Combining all measurements in all patients showed a significant correlation between QRS area reduction and %LVdP/dTmax increase (R = 0.49, P < 0.0001).  Also, when one fixed routine implantation setting was used for each patient (lateral lead position, distal, AV-delay 120-150ms, VV-delay 0ms) this correlation was present (R = 0.45, p < 0.0001, figure panel A). In 21 patients in which at least 3 lead positions were available there was also a significant correlation between QRS area reduction and %LVdP/dtmax increase (average R = 0.69, p < 0.0001, panel B). For VV-delay, 25 other patients as well showed a significant correlation (average R = 0.53, p < 0.0001).

Conclusion Within patients, QRS area reduction is associated with %LVdP/dtmax increase with various LV lead positions and VV-intervals. Therefore, QRS area, which is an easily obtainable and objective parameter, might be a promising tool for optimization of LV lead position and device programming in CRT. Abstract Figure.

P2834Diagnostic yield of holter recording after atrial fibrillation ablation - detection of asymptomatic recurrences during a one-year follow-up period

Background

Strategies to detect recurrences after atrial fibrillation (AF) catheter ablation vary widely. Whereas a symptom-based approach may overestimate procedural success due to asymptomatic recurrences, continuous invasive monitoring with implantable devices may be refused by patients and is not routinely recommended. In trial settings, Holter monitoring is recommended at one year after ablation, though more frequent and intensive follow-up is encouraged for more accurate detection of arrhythmia recurrences.

Purpose

To study the diagnostic yield of Holter monitoring in the detection of asymptomatic recurrent arrhythmias after cryoballoon catheter ablation for AF.

Methods

Prospective registry on AF patients who underwent cryoballoon ablation with subsequent follow-up in our centre. Follow-up comprised routine (i.e. at 3, 6, and 12 months) and symptom-driven electrocardiographic (ECG) registrations after a three-month blanking period. In addition, patients were scheduled for six-day Holter monitoring shortly after the blanking period, at six months and at the end of the one-year follow-up period. For the current analysis, we studied the Holter recordings of the patients without previously detected arrhythmia recurrence and determined the proportion of asymptomatic recurrences at each respective monitoring period.

Results

We studied 364 patients with a median age of 60 years (IQR 54–66) and a median CHA2DS2-VASc score of 1 (IQR 1–2). One-year recurrences were documented in 119 (32.7%) patients, of which 90 were initially detected on Holter recording and 39 on ECG registrations (Table). A total of 34 patients did not report symptoms during the documentation of recurrent arrhythmia and comprised 28.6% (34/119) of all recurrences and 37.8% (34/90) of the Holter-detected recurrences. At the three-month Holter registration, 33.3% of the patients with recurrences did not report symptoms, which was 29.4% and 62.5% at the six- and twelve-month registrations, respectively (Figure).

Timing and detection of recurrences Time after ablation 3 months 3–6 months 6 months 6–12 months 12 months Patients with Holter-detected recurrences 57/119 (47.9%) 17/119 (14.3%) 16/119 (13.4%) Patients with ECG-documented recurrences 18/119 (15.1%) 11/119 (9.2%)

Proportions of asymptomatic recurrences

Conclusions

In this cohort of AF patients with serial six-day Holter monitoring after cryoballoon ablation, up to one-third of the patients had asymptomatic recurrences. Whereas Holter monitoring shortly after the blanking period detected nearly half of all one-year recurrences, the proportion of asymptomatic detected recurrences was higher in recordings at one year and seems therefore important in the detection of asymptomatic recurrences after catheter ablation.

P5682Cardiac resynchronization therapy with a single left ventricular septal pacing electrode: acute hemodynamic and electrophysiological effects

Background

Cardiac resynchronization therapy (CRT) is usually performed with a right (RV) and left ventricular (LV) lead. In a previous patient study, pacing the interventricular septum permanently on the LV endocardial side (LV septum) proved feasible in patients with sinus node dysfunction.

Objective

To investigate the effects of LV septal pacing as compared to conventional biventricular (BiV) pacing with respect to acute hemodynamic and electrophysiological effects in CRT indicated heart failure patients.

Methods

Temporary LV septal pacing (transarterial approach) and pacing in the conventional BiV mode using the implanted leads was performed in 26 patients (QRS duration 163±17 ms, 23 left bundle branch block patients) undergoing CRT implantation. Acute hemodynamic response (relative to baseline AAI pacing) was assessed by LVdP/dtmax. Multi-electrode body-surface mapping, what has been used previously to characterize electrical dyssynchrony in CRT patients, was evaluated using the standard deviation of activation times (SDAT) (figure, right panel).

Results

LV septal pacing resulted in a significant LV dP/dtmax increase, that was comparable to conventional BiV pacing (figure, left panel). Combined RV and LV septal pacing did not provide an additional increase. LV septal pacing resulted in a significantly larger reduction in SDAT than RV plus LV septal pacing and conventional BiV pacing (figure, middle panel).

Conclusions

LV septal pacing results in acute hemodynamic improvement and electrical resynchronization that is at least as good as conventional BiV pacing. These results suggest that LV septal pacing with a single ventricular lead may serve as an alternative to conventional BiV pacing for cardiac resynchronization.

Acknowledgement/Funding

Medtronic is a subsidising party.

P6016His bundle pacing versus biventricular pacing in cardiac resynchronization therapy: acute hemodynamic and electrophysiological effects

Background

Cardiac resynchronization therapy (CRT) is usually performed with a right (RV) and left ventricular (LV) lead. Previous observational studies showed promising results with His bundle pacing (HBP) in patients with left bundle branch block (LBBB) by capturing and recruiting the native His-Purkinje system as an alternative to provide ventricular resynchronization.

Objective

To investigate the effects of HBP as compared to conventional biventricular (BiV) pacing with respect to acute hemodynamic and electrophysiological effects in heart failure patients with LBBB.

Methods

RV apical and BiV pacing, using the implanted leads, and temporary HBP, using an electrophysiology catheter, was performed in 13 patients (QRS duration 168±16 ms) undergoing CRT implantation. Hemodynamic response (relative to baseline AAI pacing) was assessed as change in LVdP/dtmax. Multi-electrode body-surface mapping, what has been used previously to characterize electrical dyssynchrony in CRT patients, was evaluated using the standard deviation of activation times (SDAT) (figure, right panel).

Results

HBP resulted in a significant LV dP/dtmax increase, that was comparable to the increase during BiV pacing and significantly larger than RV pacing (figure, left panel). HBP resulted in a more homogenized electrical activation and larger reduction in SDAT than both conventional BiV pacing and RV pacing (figure, middle panel).

Conclusions

Acute HBP results in hemodynamic improvement and electrical resynchronization that is as good as conventional BiV pacing. These results suggest that HBP may serve as an alternative for conventional BiV pacing in LBBB patients, however prospective studies are needed to prove chronic clinical outcomes.

Acknowledgement/Funding

Medtronic is a subsidising party.

When Environmental Forces Collide

Multiple factors often interact to amplify the effects of severe storms, droughts, and other extreme water-related events.

Low vitamin D levels are not a contributing factor to higher prevalence of depressive symptoms in people with Type 2 diabetes mellitus: the Hoorn study

AIM

To test whether a low serum 25-hydroxyvitamin D level explains the greater prevalence of depression among people with Type 2 diabetes.

METHODS

We performed a cross-sectional analysis of 527 people, aged 60-87 years, who participated in a population-based cohort study. Type 2 diabetes, impaired glucose tolerance, impaired fasting glucose and normal glucose tolerance were defined according to the 2006 WHO criteria. The Centre for Epidemiologic Studies Depression questionnaire was administered, using a cut-off score of ≥ 16 to determine clinically relevant depressive symptoms.

RESULTS

Logistic regression analysis confirmed that women with impaired glucose tolerance/impaired fasting glucose and people with Type 2 diabetes did have a higher risk of depressive symptoms [unadjusted odds ratios 3.66 (95% CI 1.59 to 8.43) and 3.04 (95% CI 1.57 to 5.88), respectively], compared with people with normal glucose tolerance. Serum 25-hydroxyvitamin D level was not a mediating factor in the association between impaired glucose tolerance/impaired fasting glucose or Type 2 diabetes and depressive symptoms [unstandardized indirect effect 0.001 (95% CI -0.063 to 0.079) and 0.004 (95% CI -0.025 to 0.094), respectively].

CONCLUSIONS

The study found no evidence that low vitamin D levels are a contributing factor to higher depression scores in people with Type 2 diabetes.

Effect of vitamin D supplementation on health status in non-vitamin D deficient people with type 2 diabetes mellitus

OBJECTIVE

Increased levels of depressive symptoms, fatigue or pain (all dimensions of reduced health-related quality of life (HRQOL)) are common in people with type 2 diabetes mellitus (DM). Earlier studies have reported associations between low vitamin D status and fatigue and depressive symptoms. The aim of the present study was to examine the effects of vitamin D supplementation on dimensions of HRQOL in people with type 2 DM.

DESIGN

Randomised, double-blind, placebo-controlled trial.

METHODS

The effect of monthly cholecalciferol 50,000 IU vs placebo on HRQOL was assessed in 275 adults with type 2 DM derived from general practices. HRQOL at baseline and after six months using the Short Form 36 Health Survey (SF-36) was collected. Linear regression analyses were used to compare the change in HRQOL over time between the vitamin D and placebo group.

RESULTS

187/275 (68%) completed baseline and follow-up SF-36 and were included in the analysis. Median serum 25-hydroxyvitamin D almost doubled in the intervention group compared to that in the placebo group (58.5-106.0 nmol/L vs 60.0-61.5 nmol/L, respectively). A small significant difference (adjusted B: -8.90; 95% CI: -17.16 to -0.65) between both groups was seen concerning the SF-36 domain role limitations due to physical problems in disadvantage of the vitamin D group.

CONCLUSIONS

Six months of vitamin D supplementation did not improve HRQOL in non-vitamin D-deficient people with type 2 DM managed on oral antidiabetic therapy.

Vitamin D status and health-related quality of life in patients with Type 2 diabetes

AIMS

To test whether vitamin D status was associated with health-related quality of life in people with Type 2 diabetes mellitus.

METHODS

Demographic and clinical characteristics, including health-related quality of life scores, were obtained from 241 adult patients with Type 2 diabetes managed with oral hypoglycaemic agents. Health-related quality of life was assessed using the Short-Form 36 Health Survey. Multiple logistic regression analysis was used to investigate the association between vitamin D status and health-related quality of life, with adjustment for confounders.

RESULTS

The mean age of the patients included in the study was 67 ± 8 years. Their mean HbA1c concentration was 52 ± 8 mmol/mol (6.9 ± 0.7%) and their mean serum 25-hydroxyvitamin D concentration was 59 ± 23 nmol/l. Vitamin D deficiency (serum 25-hydroxyvitamin D < 50 nmol/l) was present in 38% of patients. No significant associations were found between vitamin D status and health-related quality of life.

CONCLUSIONS

Vitamin D status was not associated with health-related quality of life in patients with Type 2 diabetes. This could be explained by the relatively high serum 25-hydroxyvitamin D concentration, good glycaemic control and relatively good health-related quality of life of all patients. A prospective study among patients with vitamin D deficiency and poor glycaemic control would be interesting for future research.

Safety and long-term effects of renal denervation: Rationale and design of the Dutch registry

BACKGROUND

Percutaneous renal denervation (RDN) has recently been introduced as a treatment for therapy-resistant hypertension. Also, it has been suggested that RDN may be beneficial for other conditions characterised by increased sympathetic nerve activity. There are still many uncertainties with regard to efficacy, safety, predictors for success and long-term effects. To answer these important questions, we initiated a Dutch RDN registry aiming to collect data from all RDN procedures performed in the Netherlands.

METHODS

The Dutch RDN registry is an ongoing investigator-initiated, prospective, multicentre cohort study. Twenty-six Dutch hospitals agreed to participate in this registry. All patients who undergo RDN, regardless of the clinical indication or device that is used, will be included. Data are currently being collected on eligibility and screening, treatment and follow-up.

RESULTS

Procedures have been performed since August 2010. At present, data from 306 patients have been entered into the database. The main indication for RDN was hypertension (n = 302, 99%). Patients had a mean office blood pressure of 177/100 (±29/16) mmHg with a median use of three (range 0-8) blood pressure lowering drugs. Mean 24-hour blood pressure before RDN was 157/93 (±18/13) mmHg. RDN was performed with different devices, with the Simplicity™ catheter currently used most frequently.

CONCLUSION

Here we report on the rationale and design of the Dutch RDN registry. Enrolment in this investigator-initiated study is ongoing. We present baseline characteristics of the first 306 participants.

[A woman with anginal symptoms and normal coronary arteries]

Angina pectoris is usually the first manifestation ofischaemic heart disease. Men are more often affected than women, but women are often denied the full diagnostic work-up of ischaemic heart disease. A 58-year-old woman had typical angina, positive exercise electrocardiography and a negative coronary arteriogram: syndrome X. She was treated with a beta blocker, aspirin, a statin and an angiotensin-converting enzyme (ACE) inhibitor, and eventually obtained relief of her symptoms.

Omental infarct: CT imaging features

BACKGROUND

The aim of this study is to describe contrast-enhanced computed tomographic (CT) features of acute omental infarction and to study the evolutionary changes on follow-up CT imaging.

METHODS

Fifteen cases of omental infarction were evaluated for their initial CT imaging features. The imaging features evaluated included size of the fatty lesion, location, peripheral rim, and relation to colon. CT findings were correlated with etiology, clinical presentation, and leukocytosis. Follow-up CT images were available in eight patients and the imaging features were studied.

RESULTS

Eight omental infarcts were of unknown etiology and seven were secondary to abdominal surgery. In 53% of patients (eight of 15), the location of the omental infarct was in the right lower, mid, or upper quadrants. These eight right-side infarcts occurred in six patients with primary omental infarcts. In 13 of 14 patients who underwent CT within 15 days of onset of omental infarct, the margin of the lesion was ill defined. Primary omental (n = 8) infarcts were seen in younger patients (p = 0.02) and were larger on CT (p = 0.02) compared with secondary omental infarcts. CT findings evolved from an ill-defined, heterogeneous fat-density lesion to a well-defined, heterogeneous fat-density lesion with a peripheral hyperdense rim in all six secondary omental infarctions for which acute stage and follow-up CT images were available for interpretation.

CONCLUSION

There is a significant difference in the age distribution and CT findings in terms of size of the omental infarction between primary and secondary etiologies. On follow-up CT, secondary omental infarcts progressively shrank and developed a well-defined, hyperdense rim around a fatty core.

Foreign gene expression in Hansenula polymorpha. A system for the synthesis of small functional peptides

We describe the synthesis and purification of two functional peptides, namely human insulin-like growth factor II (IGF-II) and Xenopus laevis magainin II in Hansenula polymorpha after their synthesis as hybrid proteins fused to the C terminus of endogenous amine oxidase. The hybrid genes, placed under control of the H. polymorpha alcohol oxidase promoter (PAOX), were integrated into the genomic alcohol oxidase locus, yielding stable production strains. High-level synthesis of the fusion proteins, exceeding 20% of total cellular protein, was obtained when the transformed strains were grown in methanol-limited chemostat cultures; when expressed by itself, i.e. in the absence of the amine oxidase gene, IGF-II could not be recovered from crude cell extracts, probably as a result of rapid proteolytic degradation. Accumulation in peroxisomes did not significantly affect the IGF-II protein stability when expressed in the absence of the carrier protein. Apparently, fusion to the large (+/- 78 kDa) amine oxidase carrier particularly stabilizes the peptides and prevents them from proteolysis. After partial purification, the fusion partners were readily separated by factor Xa treatment.