Study protocol of a cluster-randomised controlled trial assessing a multimodal machine-based exercise training programme in senior care facilities over 6 months - the bestform study (best function of range of motion)

BACKGROUND

Physical functioning is a crucial factor for independence and quality of life in old age. The aim of the "bestform-Best function of range of motion" trial is to investigate the effects of a 6 months multimodal machine-based strength, coordination and endurance training on physical function, risk of falls and health parameters in older adults.

METHODS

Bestform is a cluster-randomised trial including older adults  ≥ 65 years living in senior care facilities in Southern Germany. Senior care facilities are randomly allocated to the control group with usual care (n ≥ 10 care facilities) and to the intervention group (n ≥ 10 care facilities), overall including  ≥ 400 seniors. Residents belonging to the intervention group are offered a supervised machine-based exercise training programme twice weekly over 45-60 min over six months in small groups, while those in the usual care facilities will not receive active intervention. The primary outcome is the change in Short Physical Performance Battery over six months between groups. Secondary outcomes are change in risk of falling, fear of falling, number of falls and fall-related injuries, physical exercise capacity, handgrip strength, body composition, cardiac function, blood parameters, quality of life, risk of sarcopenia, activities of daily living, and cognition over three and six months.

DISCUSSION

The bestform study investigates the change in physical function between seniors performing exercise intervention versus usual care over six months. The results of the study will contribute to the development of effective physical activity concepts in senior care facilities.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04207307. Registered December 2019.

Associations between training characteristics and change in peak oxygen consumption following exercise training in patients with heart failure with preserved ejection fraction

Introduction

In heart failure with preserved ejection fraction (HFpEF), moderate continuous training (MCT) and high-intensity interval training (HIIT) are both effective in increasing peak oxygen uptake (peak V̇O2).

Purpose

The aim of this study was to investigate the association of training characteristics (i.e. average sessions/week, average duration/week, mean intensity) and change in peak V̇O2 following 3 months of MCT and HIIT in patients with HFpEF.

Methods

Among 120 patients who were randomized to MCT (5x40 min/week at 35–50% heart rate reserve [HRR]) or HIIT (3x38 min/week at 80–90% HRR), those who completed 3-month follow-up (N=107) were considered for this analysis. Training duration and heart rates [HR] were recorded with a smartphone application, evaluated with a customized software and manually checked for plausibility. If HR measurements were classified as invalid/unreliable (e.g. very strong fluctuations), patients were excluded from analysis. Intensities were calculated as average % HRR of total sessions in MCT and the average of the highest % HRR values of all intervals in HIIT. Associations between training characteristics and change in peak V̇O2 were evaluated using univariate and multivariate regression analyses. Individual HR-V̇O2 relationships were used to calculate and compare energy expenditure (MET-minutes) in MCT and HIIT.

Results

After excluding 16 patients due to invalid/unreliable HR data, 91 patients (67% female, 69±7 years) were included in this analysis. On average, MCT patients (N=45) performed 4.0±1.2 sessions/week (162±52 min/week) at 47.4±6.7% HRR, while HIIT patients (N=46) performed 2.4±0.8 sessions/week (96±40 min/week) at 81.8±11.8% HRR. Peak V̇O2 was improved by 1.70±2.35 ml/kg/min in MCT and 1.46±2.98 ml/kg/min in HIIT (difference: 0.24 [95% CI, −0.87 to 1.34], p=0.67). The associations between training characteristics and change in peak V̇O2 are shown in Fig.1. Mean % HRR was not significantly associated with the change in peak V̇O2 in the HIIT group, whereas in MCT, mean duration/week and mean intensity were of similar relative importance (standardized coefficients) and explained up to 26% of the variation in change in peak V̇O2 (Table 1). Average weekly MET-minutes above rest were 451±260 for MCT and 389±375 for HIIT (difference: 62 [95% CI, −71 to 195], p=0.36). After adjustment for MET-minutes, the difference in change in peak V̇O2 between groups diminished to 0.09 ml/kg/min (95% CI, −0.97 to 1.16; p=0.98).

Conclusions

Weekly duration and mean % HRR had a similar predictive ability for the change in peak V̇O2 following MCT with, interestingly, lower change in peak V̇O2 with increasing intensity. In HIIT, mean % HRR was not significantly associated with the change in peak V̇O2. After adjusting for energy expenditure, the difference in change in peak V̇O2 between training modes diminished, suggesting that MCT and HIIT were similarly effective.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Commission, Framework Program 7

Trans fatty acid blood levels and HFpEF phenotype: from the Aldo-DHF RCT

Background

Prognosis in HFpEF is determined by risk factor control and treatment of comorbidities. Industrially processed TFA (IP-TFA) from partially hydrogenated oils have been linked to altered lipoprotein metabolism, endothelial dysfunction, increased biomarkers of inflammation and increased NTproBNP. In patients with heart failure with preserved ejection fraction (HFpEF), associations of TFA blood levels with patient characteristics are unknown.

Purpose

To evaluate associations of blood TFA with cardiovascular risk factors, aerobic capacity and cardiac function in patients with HFpEF.

Methods

This is a secondary analysis from the Aldo-DHF-RCT. From 422 patients, individual blood TFA were analyzed at baseline in n=404 using the HS-Omega-3-Index® methodology. Patient characteristics were; 67±8 years, 53% female, NYHA II/III (87/13%), ejection fraction ≥50%, E/e' 7.1±1.5; median NT-proBNP 158 ng/L (IQR 82–298). Multiple linear regression analyses, using sex and age as covariates, were used to describe associations of TFA with metabolic phenotype, functional capacity, echocardiographic markers for left ventricular diastolic function (LVDF), and neurohumoral activation at baseline and after 12-months-follow-up (12mFU). To account for randomization group, all analyses were repeated as sensitivity analysis with group as covariate. A significance level of α=5% was used for all tests. As all tests were hypothesis generating without confirmatory interpretation, no correction was applied to counteract the problem of multiple comparisons.

Results

Higher blood levels of the naturally occurring TFA C16:1n-7t were broadly associated with a more favorable lipid profile, lower body weight/central adiposity, lower white blood cell count and lower biochemical markers of non-alcoholic fatty liver disease at baseline/12mFU. Conversely, blood levels of the IP-TFA C18:1n9t were directly associated with lipid risk markers [triglycerides (β=19.7, p<0,001), non-HDL-C (β=7.9, p=0,001), and LDL-C (β=5.4, p=0,011)]. The two IP-TFA C18:2n6 isomers C18:2n6tt and C18:2n6ct were positively associated with HbA1c [(β=14.6, p=0,003) and (β=4.2, p=0,014) respectively]. The IP-TFA C18:2n6tt/-ct isomers were associated with lower submaximal aerobic capacity (distance covered in the 6MWT) at baseline/12mFU. No significant association was found between TFA blood levels and left ventricular filling pressures, left ventricular relaxation or neurohumoral activation. Significant effects of group allocation (spironolactone +/−) were found for the 12mFU outcomes systolic/diastolic blood pressure (all p<0.001), heart rate, E/e$'$ and HbA1c.

Conclusions

In HFpEF patients, higher blood levels of industrially processed TFA, but not of the TFA C16:1n-7t in full fat dairy and meat, were associated with a higher risk phenotype and lower aerobic capacity. Our findings support efforts to remove IP-TFA from the food supply for improving risk factor control in HFpEF patients.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): German Foundation of Heart Research

Long term outcome after ablation of persistent atrial fibrillation in patients with postprocedurally unmasked sinus node disease

Funding Acknowledgements

Type of funding sources: None.

Background

About three percent of patients with persistent atrial fibrillation [AF] additionally suffer from a concealed sinus node disease [SND]. We sought to determine the ablation success one year after ablation of persistent AF in patients with postprocedurally unmasked SND.

Methods and Results

In total 2239 patients with an ablation of persistent AF at our center were screened for a postprocedurally unmasked SND, which made cardiac pacing necessary within one week after ablation. In a propensity score matched case control study, the longterm ablation success of 51 patients (mean age 73±8years, 58% male) with postprocedurally unmasked SND after ablation of persistent AF was compared to that of 102 patients without SND after ablation of persistent AF. Controls were matched to cases based on the propensity score considering age, body mass index, left ventricular ejection fraction, gender, blood pressure, diabetes mellitus, atrial low voltage, previous number of ablations and method of ablation.

One year after ablation of persistent AF, 20 (39%) patients with postprocedurally unmasked SND and 61 (60%) patients without postprocedurally unmasked SND were in sinus rhythm (p=0.025). The number of repeat ablation procedures within the follow up year did not differ significantly between cases and controls (0.60±0.68 vs 0.53±0.80, p=0.574).

Conclusion

In patients with a postprocedurally unmasked SND after ablation of persistent AF, longterm ablation success seems to be worse compared to patients without postprocedurally unmasked SND.

Procalcitonin as a biomarker of cardiac implantable electronic device pocket infection: a prospective validation study

Funding Acknowledgements

Type of funding sources: None.

Introduction

The implantation of cardiac implantable electronic devices (CIEDs) such as pacemakers and implantable cardioverter-defibrillators is increasing along with the complexitly of these devices. CIED infection is an uncommon, but severe complication associated with the presence of a device and is associated with a high mortality and morbidity. Lead-related infections and frank endocarditis are associated with a systemic inflammatory response and, in general, are readily identified. Isolated pocket infections do not produce such a systemic response and are thus more complex to diagnose. There is a reliance on clinical accumen and examination of local signs of infection. There is thus a need for a reliable biomaker to help identify cases of pocket infection.

Aim

Our group have previously shown procalcitonin (PCT) to be a potentially useful biomaker in the clinial situation of possible pocket infection. We aim to prospectively validate the proposed cut-off value of 0.05ng/ml for the procalcitonin (PCT) biomaker in an independent cohort, which we have previously identified as showing promise in this clinical situation.

Methods

In this prospective case-control validation study the PCT levels of 81 patients with confirmed pocket infections were compared to 81 controls, matched for age and renal function, presenting for elective generator replacement or lead revision unrelated to infection. Exclusion criteria included: concomitant infectious or inflammatory diseases, end-stage renal failure, active malignancy or receiving immunosuppressive therapy.

Results

A PCT over 0.05 ng/ml was found in 68% (n= 55) of pocket infections and 24% (n= 19) of controls. Using the pre­defined cut-off value of 0.05 ng/ml PCT had a sensitivity of 68% and a specificity of 77% for diagnosing pocket infections. ROC analysis revealed area under the curve of 0.752 (standard error 0.039, p <0.001 ) for PCT. In patients presenting with minimal infective signs the sensivity remained high (67% vs 70% with extensive inflammation) and similarly remained high in thus who had received anti-biotic therapy prior to PCT sampling (65% vs 69%).

Conclusion

PCT is a potentially useful biomarker to aid the diagnosis of a pocket infection when used with the prospecitvely validated cut-off value of 0.05ng/ml. The sensitivity of the PCT positive result remained high even in patients pre-treated with antibiotics or with minimal clinical signs of inflammation.

Marathon running improves mood and negative affect

BACKGROUND

Physical activity has beneficial effects on depression, as well as on other mental and somatic diseases. The amount of recommended exercise is still under discussion. We investigated whether marathon runners (MA) exhibit less or more depressive symptoms and negative affects compared to sedentary controls (SC) and how their mood changes in the context of marathon training and marathon running.

METHODS

We included 100 amateur marathon runners and 46 age- and gender matched sedentary controls in the ReCaP (Running effects on Cognition and Plasticity) study. Questionnaires contained Beck Depression Inventory (BDI), Hamilton Depression Scale (HAMD), Oxford Happiness Questionnaire (OHQ), Visual Analogue Scale (VAS), Positive And Negative Affect Schedule (PANAS), Global Assessment of Functioning (GAF). SC were evaluated one time at baseline, MA six times during the six months study period.

RESULTS

Compared to SC, marathon runners (281.80 ± 131.44 running min/week) exhibited less depressive symptoms, more positive affects (PANAS-PA) and a higher level of functioning (GAF). Within the marathon group, negative affect (PANAS-NA) decreased and general mood states (VAS) further improved throughout the study period with a maximum 24 h after the marathon.

DISCUSSION

MA had less depressive symptoms and a higher level of functioning compared to SC. Higher amounts than the recommended duration of 150 min/week aerobic training (WHO/ACSM) and the participation in a marathon seem to even further improve negative affect. These findings give new insight into the relationship between exercise and mood parameters. They can be implemented in future preventive strategies for depressive symptoms.

Fetal heart rate variability responsiveness to maternal stress, non-invasively detected from maternal transabdominal ECG

PURPOSE

Prenatal stress (PS) during pregnancy affects in utero- and postnatal child brain-development. Key systems affected are the hypothalamic-pituitary-adrenal axis and the autonomic nervous system (ANS). Maternal- and fetal ANS activity can be gauged non-invasively from transabdominal electrocardiogram (taECG). We propose a novel approach to assess couplings between maternal (mHR) and fetal heart rate (fHR) as a new biomarker for PS based on bivariate phase-rectified signal averaging (BPRSA). We hypothesized that PS exerts lasting impact on fHR.

METHODS

Prospective case-control study matched for maternal age, parity, and gestational age during the third trimester using the Cohen Perceived Stress Scale (PSS-10) questionnaire with PSS-10 over or equal 19 classified as stress group (SG). Women with PSS-10 < 19 served as control group (CG). Fetal electrocardiograms were recorded by a taECG. Coupling between mHR and fHR was analyzed by BPRSA resulting in fetal stress index (FSI). Maternal hair cortisol, a memory of chronic stress exposure for 2-3 months, was measured at birth.

RESULTS

538/1500 pregnant women returned the questionnaire, 55/538 (10.2%) mother-child pairs formed SG and were matched with 55/449 (12.2%) consecutive patients as CG. Maternal hair cortisol was 86.6 (48.0-169.2) versus 53.0 (34.4-105.9) pg/mg (p = 0.029). At 36 + 5 weeks, FSI was significantly higher in fetuses of stressed mothers when compared to controls [0.43 (0.18-0.85) versus 0.00 (- 0.49-0.18), p < 0.001].

CONCLUSION

Prenatal maternal stress affects the coupling between maternal and fetal heart rate detectable non-invasively a month prior to birth. Lasting effects on neurodevelopment of affected offspring should be studied.

TRIAL REGISTRATION

Clinical trial registration: NCT03389178.

Influence of antiretroviral therapy and cardiovascular disease on the immature platelet fraction in patients living with HIV

Cardiovascular disease is an important contributor to morbidity and mortality in people living with HIV . The immature platelet fraction (IPF) is increased in HIV-negative patients with cardiovascular disease and evidence suggests that an enlarged IPF is associated with adverse cardiovascular events. In this multi-center observational study, we aimed to investigate how the IPF in people living with HIV is influenced by antiretroviral therapy and cardiovascular disease. Subjects without cardiovascular disease that received antiretroviral therapy showed a smaller IPF accompanied by lower D-dimer and C-reactive protein (CRP) levels compared to therapy-naïve subjects (mean IPF: 2.9% vs. 3.9%, p = .016; median D-dimer: 252 µg/L vs. 623 µg/L, p < .001; median CRP: 0.2 mg/dL vs. 0.5 mg/dL, p = .004). No significant differences for the IPF, D-dimer or CRP were found between subjects on antiretroviral therapy with documented cardiovascular disease and therapy-naïve subjects. In conclusion, we observed a reduction in the IPF among subjects on therapy only in the absence of cardiovascular disease. In contrast, subjects receiving therapy that had documented cardiovascular disease showed an IPF comparable to therapy-naïve subjects. Future studies are needed to investigate if an enlarged IPF may serve as a biomarker in predicting adverse cardiovascular events in people living with HIV.

Three-dimensional fat-saturated T1-weighted Cartesian volumetric interpolated breath-hold examination (VIBE) for the diagnosis of aortitis in patients with suspected large vessel vasculitis: a comparative study with 18F-FDG PET applying fully integrated PET/MRI

AIM

To evaluate the feasibility of T1-weighted (T1W) three-dimensional (3D) fat saturated Cartesian volumetric interpolated breath-hold examination (VIBE) magnetic resonance imaging (MRI) sequence for the diagnosis of aortitis in patients with suspected large vessel vasculitis (LVV) applying fully integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/MRI.

MATERIAL AND METHODS

Fourteen patients with aortitis and 14 patients with a negative study for aortitis using ¹⁸F-FDG PET as the standard of reference for the evaluation of inflammatory aortic involvement were included retrospectively. All patients were imaged at 3 T using T1W VIBE pre- and post-contrast. Four aortic segments were evaluated for image quality (IQ), diagnostic confidence (DC), and the degree of inflammatory activity (IA) using a Likert scale. Binomial and generalised estimating equation model tests were used to assess the diagnostic performance of T1W VIBE. Cohen's k was applied to test for interobserver reproducibility with respect to IA. Spearman's rank correlation coefficient was calculated to examine correlations between IQ, DC, IA, and PET results.

RESULTS

On a patient- and segment-based analysis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 85.7% and 59.8%, 100% and 100%, 100% and 100%, 87.5% and 68%, and 92.9% and 82.1%, respectively. IQ and DC were acceptable to good in all examinations and substantial interobserver agreement was observed for IA (Cohen's k = 0.69). IQ and DC as well as IA and ¹⁸F-FDG vessel wall uptake were significantly correlated (r=0.763 and 0.679, respectively; p<0.0001).

CONCLUSION

T1W 3D fat saturated VIBE MRI allows diagnosis of aortitis and may aid in the management of patients with suspected LVV.

T2-relaxation time of cartilage repair tissue is associated with bone remodeling after spongiosa-augmented matrix-associated autologous chondrocyte implantation

OBJECTIVE

To investigate whether T2 relaxation time measurements of cartilage repair tissue and structural changes of the knee joint are associated with subchondral bone architecture after spongiosa-augmented matrix-associated autologous chondrocyte implantation (MACI).

DESIGN

Both knees of 25 patients (25.5 ± 7.8y; 10 women) were examined preoperatively and 2.7 years after unilateral spongiosa-augmented MACI with 3T magnetic resonance (MR) imaging. Cartilage composition was assessed using T2 relaxation time measurements, subchondral trabecular bone microstructure was quantified using a 3D phase-cycled balanced steady state free-precision sequence. Structural knee joint changes were assessed using the modified Whole-Organ Magnetic Resonance Imaging Score (WORMS). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was used for the postoperative description of the area that underwent MACI. Correlations were assessed using Spearman's rank correlation coefficients.

RESULTS

Hypertrophy of the cartilage repair tissue was found in 2 of 25 patients, both after a MACI procedure at the patella, 21 patients showed congruent filling. In subchondral bone of the cartilage repair compartment, apparent trabecular thickness was significantly higher in compartments with elevated cartilage T2 (n = 17; 0.37 ± 0.05 mm) compared to those showing no difference in cartilage T2 compared to the same compartment in the contralateral knee (n = 8; 0.27 ± 0.05 mm; P = 0.042). Significant correlations were found between the overall progression of WORMS and the ipsilateral vs contralateral ratio of average trabecular thickness (r = 0.48, P = 0.031) and bone fraction (r = 0.57, P = 0.007).

CONCLUSIONS

After spongiosa-augmented MACI, T2 values of cartilage repair tissue and structural knee joint changes correlated with the quality of the underlying trabecular bone.

Primary Stability of an Acromioclavicular Joint Repair Is Affected by the Type of Additional Reconstruction of the Acromioclavicular Capsule

BACKGROUND

The synergistic effect of the acromioclavicular (AC) capsule and coracoclavicular (CC) ligaments on AC joint stability has gained recent recognition for its importance. Biomechanical and clinical studies have shown the benefit of combined reconstruction with multiple variations of surgical techniques for AC capsule augmentation. The ideal configuration remains unknown for such capsular repair aimed at achieving optimal stability with anatomic reconstruction.

HYPOTHESIS

Primary AC joint stability can be restored by AC capsule augmentation, while position of the additional suture construct is critical. It was hypothesized that techniques that reconstruct the anterior capsular structures would restore native stability against rotations and translations.

STUDY DESIGN

Controlled laboratory study.

METHODS

Thirty fresh-frozen human cadaveric shoulders were used. Each sample was tested in the native state and served as its own control. After complete capsulotomy, 1 of 5 AC capsular repair configurations was performed: anterior, superior, posterior, O-frame, and X-frame. After testing of the AC capsular repair configurations, the tests were repeated after dissection of the CC ligaments and after CC ligament reconstruction with a suture button system. AC joint stability was immediately tested after each step under rotation and horizontal translation. To accomplish this, the AC joints were anatomically positioned on a custom fixture linked to a servohydraulic testing system. A 3-dimensional optical measuring system was used to evaluate the 3-dimensional joint motion. Clavicle posterior translation in relation to the acromion, rotation around the long axis of the clavicle, and displacement of the lateral clavicle in relation to the center of rotation were measured. The torques and forces required to rotate and translate the clavicle were recorded.

RESULTS

In terms of translational testing, after the complete capsulotomy, a significant reduction of resistance force was found across all groups, with a mean 13% to 20% remaining ( P < .05). All AC suture augmentations were able to significantly increase the average resistance force as compared with the native ( P = .01) against posterior translation. Subsequent cutting of the CC ligaments did not result in a significant change in any of the groups ( P = .23). The synergistic effect of AC capsule augmentation and CC ligament reconstruction could be demonstrated without exception. In terms of rotational testing, the complete capsulotomy resulted in a significant reduction of resistance torque in all groups ( P < .05), with a remaining torque ranging between 2% and 11% across the groups. However, all AC suture constructs significantly increased the resistance torque as compared with the capsulotomy ( P = .01). The subsequent cutting of the CC ligaments resulted in a significant change in 2 of the 5 groups (O-frame, P = .01; X-frame, P = .02) and an overall remaining torque reduction ranging from 3% and 42%. The combined reconstruction of the AC capsule and CC ligaments achieved the highest percentage of regained resistance torque but remained significantly weaker than the native specimen ( P = .01).

CONCLUSION

Native translational stability could be restored by the addition of AC capsule augmentation, while partial rotational instability remained. The tested constructs revealed no significant individual differences.

CLINICAL RELEVANCE

Combined stabilization of the AC capsule and CC ligaments demonstrated the greatest capacity to restore the native stability against translational and rotational loads, with the specific configuration of the AC capsule repair to be chosen according to the personal preferences of the surgeon.

Influence of gestational diabetes on fetal autonomic nervous system: a study using phase-rectified signal-averaging analysis

OBJECTIVES

Maternal gestational diabetes mellitus (GDM) is known to influence fetal physiology. Phase-rectified signal averaging (PRSA) is an innovative signal-processing technique that can be used to investigate fetal heart signals. The PRSA-calculated variables average acceleration capacity (AAC) and average deceleration capacity (ADC) are established indices of autonomic nervous system (ANS) function. The aim of this study was to evaluate the influence of GDM on the fetal cardiovascular and ANS function in human pregnancy using PRSA.

METHODS

This was a prospective clinical case-control study of 58 mothers with diagnosed GDM and 58 gestational-age matched healthy controls in the third trimester of pregnancy. Fetal cardiotocography (CTG) recordings were performed in all cases at entry to the study, and a follow-up recording was performed in 19 GDM cases close to delivery. The AAC and ADC indices were calculated by the PRSA method and fetal heart rate short-term variation (STV) by CTG software according to Dawes-Redman criteria.

RESULTS

Mean gestational age of both groups at study entry was 35.7 weeks. There was a significant difference in mean AAC (1.97 ± 0.33 bpm vs 2.42 ± 0.57 bpm; P < 0.001) and ADC (1.94 ± 0.32 bpm vs 2.28 ± 0.46 bpm; P < 0.001) between controls and fetuses of diabetic mothers. This difference could not be demonstrated using standard computerized fetal CTG analysis of STV (controls, 10.8 ± 3.0 ms vs GDM group, 11.3 ± 2.5 ms; P = 0.32). Longitudinal fetal heart rate measurements in a subgroup of women with diabetes were not significantly different from those at study entry.

CONCLUSIONS

Our findings show increased ANS activity in fetuses of diabetic mothers in late gestation. Analysis of human fetal cardiovascular and ANS function by PRSA may offer improved surveillance over conventional techniques linking GDM pregnancy to future cardiovascular dysfunction in the offspring. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Trends in Patient Safety of Intact Abdominal Aortic Aneurysm Repair: German Registry Data on 36,594 Procedures

OBJECTIVE/BACKGROUND

The study aim was to determine whether patient safety for non-ruptured abdominal aortic aneurysm (nrAAA) repair has changed between 1999 and 2010 in a large German cohort.

METHODS

The data source was the prospective quality assurance registry of the German Vascular Society from 1999 to 2010. Patient characteristics, surgical techniques (open aortic repair [OAR], endovascular aortic repair [EVAR]), procedural time and outcomes, including the length of hospital stay (LOS), were analysed using the Cochran-Armitage test for binary parameters and Spearman's correlation coefficient for quantitative parameters.

RESULTS

A total of 36,594 operations (23,037 OAR, 13,557 EVAR) for infrarenal nrAAA in 201 hospitals in Germany were investigated. Patients' mean age increased from 69.6 to 72.0 years (p < .001). The rate of patients with American Society of Anesthesiologists scores of 3 or 4 increased (p < .001). Use of EVAR increased (1999: 16.7%; 2010: 62.7%; p < .001), and since 2009, EVAR has been more frequently used than OAR. The overall in hospital mortality decreased from 3.1% in 1999 to 2.3% in 2010 (p < .001). There were no temporal trends for mortality rates for EVAR (p = .233) or OAR (p = .281) when considered separately. Cardiac (1999: 8.1%; 2010: 5.1%; p < .001) and pulmonary (1999: 7.8%; 2010: 4.8%; p < .001) complications decreased. The rate of post-operative renal failure increased (1999: 3.6%; 2010 4.1%; p = .017), without increasing the rate of patients needing dialysis (1999: 1.7%; 2010: 1.7%; p = .171). The median LOS decreased from 17 days in 1999 to 10 days in 2010 (p < .001).

CONCLUSION

This study shows significantly improved post-procedural in hospital outcomes and decreased use of resources for nrAAA repair. This trend can probably be attributed to the implementation of EVAR as a standard technique, but some trends could also possibly be explained by a change in the remuneration system. The main limitation of the registry is the lack of internal and external validation. However, in hospital patient safety for AAA repair seems to have improved significantly in the participating hospitals.

Esophageal bougination: a novel ex vivo endoscopic training model correlated with clinical data

BACKGROUND

Esophageal bougination is a worldwide standard endoscopic procedure. Clinical methods and recommendations are based on clinical experiences only. Mechanical properties have never been described. Aim of the study was to establish a realistic ex vivo training model. Therefore, detailed assessment of relevant mechanical features of esophageal bougination should be evaluated ex vivo and in patient setting and correlated against.

PATIENTS AND METHODS

A three-step concept was used to evaluate mechanical properties at stenosis level. First, insertion forces were evaluated in an ex vivo linear single stenosis model during steady mechanical insertion. Second, adding friction and properties of the pharynx and upper esophagus, the model was integrated in an artificial endoscopic training model (ELITE training model). Third, in vivo measurements were taken to correlate ex vivo data with parameters of a realistic patient setting.

RESULTS

With the presented setup, we were able to assess insertion force and pressure levels in an artificial stricture using different sizes of commercially available standard bougies. In all models, there was a relevant increase in insertion force with higher stricture pressure levels. Insertion force levels in the ELITE model show higher levels compared to the linear stenosis model. Having regard to the maximum forces in patients, there is also a constant increase in mean insertion force according to higher bougie sizes, but lower forces were measured as in the ELITE model.

DISCUSSION

The applied models are suitable to appraise mechanical properties of esophageal bougination in an ex vivo model and patient setting. Forces could be constituted reliable, significant increase was documented according to stenosis level and results were comparable to patient data. This was comparable to patient data. Further clinical evaluation in different kinds of stenosis is necessary.

Measurements After Image Post-processing Are More Precise in the Morphometric Assessment of Thoracic Aortic Aneurysms: An Intermodal and Intra-observer Evaluation

OBJECTIVES

Precise pre-procedural anatomical analysis of aneurysmal anatomy is essential for successful thoracic endovascular aortic repair (TEVAR). Since surgeons and radiologists have to perform multiple measurements in the same patient, high intra-observer reliability of any imaging method is mandatory. Commercially available three dimensional (3D) post-processing techniques are expected to be superior to conventional two dimensional multiplanar reconstructions (MPRs) derived from computed tomography angiograms (CTAs). However, few data exist to support this view. This study aims to evaluate the intermodal and intra-observer differences using 3D software (3surgery) in descending thoracic aortic aneurysms (dTAAs).

METHODS

Pre-operative CTAs (performed between 2004 and 2010) of 30 dTAAs (mean maximum diameter 61.4 ± 13 mm) were assessed by three independent investigators with different experience in the measurement of aortic pathologies. Intra-observer reliability and intermodal differences (3D vs. 2D) were investigated using pre-specified measurement points (distances of total length, maximum diameter, proximal and distal landing zones). Statistical analyses were performed using the Bland-Altman method and a mixed regression model.

RESULTS

Intermodal comparison showed that 2D measurements significantly underestimate the measured distances (maximum diameter 3.7 mm [95% CI -5.3 to -2.1] and landing zone maximum 1.4 mm [95% CI -2.0 to -0.2] shorter with 2D, p < .05). In almost all 3D measurements, all investigators showed lower variability comparing the intra-observer differences, most notably in the measuring point total length (reduction of the SD up to 7.9 mm).

CONCLUSIONS

These data show that both techniques led to significant measurement disparity. This occurs especially at the point of indication (maximum diameter) and the total length of the aneurysm (important for correct stent graft selection). But overall the variability is reduced with the 3D technique, which also tends to measure greater distances. The use of post-processing software therefore leads to more precise device selection for TEVAR in TAA.

Patient characteristics and outcomes of carotid endarterectomy and carotid artery stenting: analysis of the German mandatory national quality assurance registry - 2003 to 2014

AIM

In Germany, every surgical or endovascular procedure on the extracranial carotid artery is documented in a mandatory quality assurance registry. The purpose of this study is to describe the patient characteristics, the indications for treatment, and the short-term outcomes as well as to analyse the corresponding trends from 2003 to 2014.

METHODS

Data on demographics, peri-procedural measures, and outcomes were extracted from the annual quality reports published by the Federal Agency for Quality Assurance and the Institute for Applied Quality Improvement and Research in Health Care. Data were available from 2003 to 2014 for carotid endarterectomy (CEA) and from 2012 to 2014 for carotid artery stenting (CAS). The primary outcome event of this study is any stroke or death until discharge from hospital. Temporal trends of categorical variables were statistically analysed using the Cochran-Armitage test for trend.

RESULTS

Between 2003 and 2014, 309,405 CEAs and 18,047 CAS procedures were documented in the database; 68.1% of all patients were male. The mean age of patients treated with CEA increased from 68.9 years in 2003 to 70.9 years in 2014. The proportion of patients with ASA stages III to V increased from 65% to 71% in CEA, whereas it decreased from 44% to 41% in CAS patients. 53.1% of all CEAs were performed for asymptomatic patients (group A), 34.4% for symptomatic patients treated electively (group B), and 11.2% a in a collective group including other indications for CEA or CAS (such as recurrent stenosis, carotid aneurysms, emergency treatment due to stroke-in-evolution). The corresponding data for CAS are 49.3%, 26.1% and 26.3% respectively. In group B, the interval between the neurological index event and CEA decreased from 28 to 8 days (P<0.001). In patients treated with CAS, this interval was 9 days in 2012 (no further data available). On average, 67.1% and 48.2% of surgically treated patients as well as 77.8% and 69.8% of CAS patients were neurologically assessed before and after the procedure, respectively. From 2003 to 2014, CEA procedures were performed more frequently in locoregional anesthesia (10.1% to 29.1%, P<0.001). The same trend was observed for the application of the eversion technique (37.0% to 41.6%, P<0.001), the neurophysiological monitoring (49.8% to 61.8%, P<0.001), and the intra-procedural assessment of the treated artery (44.5% to 69.7%, P<0.001). In contrast, shunting was used less frequently (48.1% to 43.0%, P<0.001). Averagely 95.7% of all endovascular procedures were performed using stent-angioplasty. In 54.2% a protection device was used. Nitinol and bare metal stents were used in 74.1% and 21.4% of cases, respectively. The in-hospital rate of any stroke or death decreased from 2.0% to 1.1% in asymptomatic patients treated with CEA without a contralateral stenosis ≥75% or occlusion, P<0.001). In patients treated with CAS this rate did not increase (1.7% to 1.8%, p=0.909). The corresponding rates in CEA and CAS patients with severe contralateral stenosis or occlusion varied between 1.9%-3.1% and 2.2%-2.6%, respectively. In symptomatic patients (group B) with a stenosis of 50 percent or more, the rate of any stroke or death decreased significantly after CEA from 4.2% to 2.4% (P<0.001) and remained stable after CAS (3.9% to 3.5%, P=0.577).

CONCLUSION

This report on 327,452 carotid procedures analysed one of the largest quality registries on CEA and CAS worldwide. Data indicate that treated patients became older and sicker, whereas in contrast, the in-hospital rates of stroke or death are decreasing over time.

The prognostic effect of tumour-infiltrating lymphocytic subpopulations in bladder cancer

BACKGROUND

Intratumoural lymphocytic infiltration is strongly associated with the outcome of many human epithelial cancers. The current paper investigated whether subpopulations of tumour-infiltrating T lymphocytes are associated with certain clinicopathological parameters and the prognosis of patients with invasive bladder cancer (BCa).

PATIENTS AND METHODS

The infiltration densities of the adaptive immune markers CD3 (the whole T cell population), FOXP3 (regulatory T cells; Tregs), CD8 (T effector cells) and CD45R0 (T effector memory cells) were analysed by immunohistochemistry and image analysis with tissue microarrays of tumour tissues from 149 patients with invasive BCa treated with radical cystectomy. The findings were correlated with certain clinicopathological parameters.

RESULTS

Higher FOXP3/CD3 [OS: p = 0.016, HR 1.29, 95% confidence intervals (95% CIs 1.05-1.59)] and FOXP3/CD8 (OS: p = 0.013, HR 1.32, 95% CIs 1.06-1.65) ratios were significantly associated with briefer overall survival and time to cancer-specific death; the latter ratio represented an independent prognostic factor according to a multivariate analysis adjusted for pathological T and N stages (HR 1.32, 95% CIs 1.05-1.67, p = 0.018). The infiltration densities of individual markers (CD3, CD8, FOXP3 and CD45R0) were not significantly associated with clinicopathological parameters or survival; however, a trend towards a better outcome was observed for higher log-transformed CD8 (p = 0.070, HR 0.80, 95% CIs 0.63-1.02) and CD3 (p = 0.113, HR 0.84, 95% CIs 0.68-1.04) infiltration values.

CONCLUSIONS

A high fraction of Tregs amongst CD3- and CD8-positive lymphocytes indicated a poor prognosis, thereby emphasising the important role that Tregs play in the suppression of the anti-tumour immune response. No single lymphocytic marker was significantly correlated with clinical outcomes, but high CD3 and CD8 infiltration showed trends towards better prognosis.

[Indication-Related Effectivity of Cervical Occlusion Techniques in Women with Threatening Preterm Birth]

The aim of this study was to identify which operation technique [total cervical occlusion (TMV), cerclage (C) or combination of both (TMV+C)] would lead to the greatest pregnancy prolongation in 3 different collectives of patients at risk (history of preterm birth, cervical insufficiency, prolapsing membranes). In this retrospective data collection, 200 cervical occlusions performed between 1997 and 2010 were analysed. In patients with a history of preterm birth/stillbirth (n=80) a prophylactic TMV increased the lifebirth rate from 35% without TMV to 95% with TMV (p<0.001). The risk diminuation after TMV was - 60% for stillbirth (p<0.001) and - 30% for preterm birth (p=0.01). In this subcollective the TMV seemed to be more effective in pregnancy prolongation (days) than C (139 vs. 113 days), however the combination of both (C+TMV) did not add much benefit (142 days). In patients with cervical insuffiency (n=86) the pregnancy could be prolonged by 82 (C), 79 (TMV) und 109 days (C+TMV) (p=0.003-0.017) and in patients with membrane prolaps (n=34) by 63 (C), 61 (TMV) und 76 (C+TMV) days. According to present data, the combination of cerclage and TMV has the highest benefit on pregnancy prolongation. This analysis should provide a basis for randomised controlled studies on this topic.

Prevalence and correlates of young people's sexual aggression perpetration and victimisation in 10 European countries: a multi-level analysis

Data are presented on young people's sexual victimisation and perpetration from 10 European countries (Austria, Belgium, Cyprus, Greece, Lithuania, the Netherlands, Poland, Portugal, Slovakia and Spain) using a shared measurement tool (N = 3480 participants, aged between 18 and 27 years). Between 19.7 and 52.2% of female and between 10.1 and 55.8% of male respondents reported having experienced at least one incident of sexual victimisation since the age of consent. In two countries, victimisation rates were significantly higher for men than for women. Between 5.5 and 48.7% of male and 2.6 and 14.8% of female participants reported having engaged in a least one act of sexual aggression perpetration, with higher rates for men than for women in all countries. Victimisation rates correlated negatively with sexual assertiveness and positively with alcohol use in sexual encounters. Perpetration rates correlated positively with attitudes condoning physical dating violence and with alcohol use in men, and negatively with sexual assertiveness in women. At the country level, lower gender equality in economic power and in the work domain was related to higher male perpetration rates. Lower gender equality in political power and higher sexual assertiveness in women relative to men were linked to higher male victimisation rates.

Prevalence and correlates of young people's sexual aggression perpetration and victimisation in 10 European countries: a multi-level analysis

Data are presented on young people's sexual victimisation and perpetration from 10 European countries (Austria, Belgium, Cyprus, Greece, Lithuania, the Netherlands, Poland, Portugal, Slovakia and Spain) using a shared measurement tool (N = 3480 participants, aged between 18 and 27 years). Between 19.7 and 52.2% of female and between 10.1 and 55.8% of male respondents reported having experienced at least one incident of sexual victimisation since the age of consent. In two countries, victimisation rates were significantly higher for men than for women. Between 5.5 and 48.7% of male and 2.6 and 14.8% of female participants reported having engaged in a least one act of sexual aggression perpetration, with higher rates for men than for women in all countries. Victimisation rates correlated negatively with sexual assertiveness and positively with alcohol use in sexual encounters. Perpetration rates correlated positively with attitudes condoning physical dating violence and with alcohol use in men, and negatively with sexual assertiveness in women. At the country level, lower gender equality in economic power and in the work domain was related to higher male perpetration rates. Lower gender equality in political power and higher sexual assertiveness in women relative to men were linked to higher male victimisation rates.

Impact of baseline atrial fibrillation cycle length on acute and long-term outcome of persistent atrial fibrillation ablation

BACKGROUND

A short baseline atrial fibrillation (AF) cycle length (CL) has been associated with a worse outcome after catheter ablation for AF, whereas the impact of a long baseline AFCL is unknown. We investigated the influence of AFCL on acute and long-term success in a large series of patients undergoing catheter ablation for persistent AF.

METHODS

Overall, 177 consecutive patients undergoing catheter ablation of persistent AF using a sequential ablation approach were included in the analysis. AFCL was measured in the left atrial appendage (LAA) at baseline and following each ablation step. The primary endpoint was freedom from any atrial arrhythmia off antiarrhythmic drugs (AAD) with a single ablation procedure after 12 months.

RESULTS

Mean AFCL was 164 ± 24 ms. A shorter AFCL was associated with longer AF duration, larger LA diameter, and longer procedure duration. Termination to sinus rhythm (SR) was achieved in 57 (32 %) patients. Baseline AFCL was shorter (161 ± 24 ms) in patients without AF termination compared to patients with AF termination (169 ± 23 m, p = 0.03). The primary endpoint was reached less frequently in patients with a short (<155 ms) AFCL (18 vs. 38.5 %, p = 0.006). Patients with an AFCL between 155 and 200 ms had the best outcome compared to patients with AFCL <155 or ≥200 ms (40 vs. 18 %, p = 0.003).

CONCLUSIONS

Patients with a baseline AFCL between 155 and 200 ms have the best outcome after a single ablation procedure for persistent AF compared to patients with an AFCL of <155 or ≥200 ms.

Association of leptin and insulin with childhood obesity and retinal vessel diameters

OBJECTIVE

Childhood obesity is associated with an impaired retinal microcirculation. The aim of the study was to investigate the association between specific obesity-related biomarkers, physical fitness and retinal vessel diameters in school children.

DESIGN AND SUBJECTS

We studied 381 children aged 10-11 years (body mass index (BMI): 19.3±3.7 kg m(-2)) in a school-based setting.

MEASUREMENTS

Anthropometric measurements and blood sampling were conducted using standard protocols for children. The serum biomarkers leptin, adiponectin, insulin as well as interleukin-6 (IL-6) were analyzed. Physical fitness was determined by a six-item-test battery and physical activity by use of a questionnaire. Central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE) and the arteriolar-to-venular diameter ratio (AVR) were assessed with a non-mydriatic vessel analyzer (SVA-T) using a computer-based program.

RESULTS

Compared with normal weight children (n=254), obese children (n=39) showed higher leptin (P<0.001), higher insulin (P<0.001), higher IL-6 (P<0.001) and lower adiponectin levels (P=0.013). Obese children demonstrated wider CRVE (P=0.041) and lower AVR (P<0.001). Higher leptin levels were associated with wider CRVE (P=0.032) and lower AVR (P=0.010), that was BMI dependent. Insulin levels were associated with arteriolar (P=0.045) and venular dilatation (P=0.034) after adjustment for BMI. No significant associations between adiponectin levels, IL-6 levels, physical fitness or physical activity and retinal vessel diameter were observed. Lower leptin levels were independently correlated with higher physical fitness (r=-0.33; P<0.001).

CONCLUSION

Leptin and insulin levels are associated with changes of the retinal microcirculation. Especially insulin seems to be a good target marker for the cardiometabolic risk assessment in children since elevated insulin levels are independently associated with microvascular end-organ alterations at an early stage. Lifestyle intervention studies are warranted to examine whether improvement of physical fitness or weight reduction can affect cardiometabolic risk markers and reverse alterations of the retinal microcirculation.

Clinical manifestations and treatment options in patients with cirrhosis and diabetes mellitus

BACKGROUND

Diabetes is frequently diagnosed in patients with cirrhosis and represents an important risk factor for morbidity and mortality. Pharmacological therapy is limited due to hepatotoxicity and the risk of hypoglycemia. Investigations on medical practice in this patient population, frequency of diabetes-associated complications and the impact of quality of metabolic control are rare.

AIMS AND METHODS

A retrospective analysis was performed to compare the effects of hypoglycemic treatment, the achieved glycemic control under therapy, the prevalence of typical cirrhosis-related or microangiopathic complications, and cardiovascular comorbidities between a group of diabetic patients with cirrhosis (n = 87) and a nondiabetic cirrhotic population (n = 198).

RESULTS

The prevalence of diabetes in our cohort was 30.5%. Of all diabetic patients, 39.1% received therapy which might potentially result in serious side effects in patients with end-stage liver disease. The rate of ongoing alcohol abuse (28.7%) and noncompliance under medication (41.4%) was high. Only 28.7% of all diabetic subjects showed satisfactory (as defined by HbA1c ≤ 6.5%) glycemic control under therapy. Patients achieving satisfactory control experienced a lower rate of certain cirrhosis-related complications such as hepatic encephalopathy (HE) and hepatocellular carcinoma (HCC), arterial hypertension, and hypercholesterolemia. HE was significantly more frequent in diabetic than nondiabetic cirrhotic patients.

Impact of pathologic complete response on disease-free survival in patients with esophagogastric adenocarcinoma receiving preoperative docetaxel-based chemotherapy

BACKGROUND

The aim of this study was to evaluate the impact of pathologic complete response (pCR) on outcome in patients with gastric or esophagogastric junction (EGJ) adenocarcinoma after neoadjuvant docetaxel/platin/fluoropyrimidine-based chemotherapy.

PATIENTS AND METHODS

Patients received at least one cycle of chemotherapy for potentially operable disease. Pretreatment clinicopathologic factors and pCR were investigated. Disease-free survival (DFS), overall survival (OS) and tumor-related death were correlated with pCR.

RESULTS

One hundred twenty patients were included in this analysis. Eighteen patients (15%) achieved a pCR. Tumor localization in the EGJ was identified as the only significant predictor of pCR (P = 0.019). Median follow-up was 41.1 months. Median DFS and OS for all patients were 24.1 and 48.6 months, respectively. Median DFS for patients with a pCR was not reached versus 22.1 months non-pCR patients (hazard ratio, HR 0.38; 3-year DFS: 71.8% and 37.7%, respectively, P = 0.018). While OS was not significantly different, the risk for tumor-related death was significantly lower for pCR patients compared with non-pCR patients (3-year cumulative incidences of 6.4% and 45.4%, respectively, P = 0.009).

CONCLUSION

A pCR following preoperative docetaxel/platin/fluoropyrimidine indicates favorable outcome in patients with gastric or EGJ adenocarcinoma. Tumor location in the EGJ is associated with a higher pCR rate.

Ultrashort echo time (UTE) MRI for the assessment of caries lesions

OBJECTIVE

Direct in vivo MRI of dental hard tissues by applying ultrashort echo time (UTE) MRI techniques has recently been reported. The objective of the presented study is to clinically evaluate the applicability of UTE MRI for the identification of caries lesions.

METHODS

40 randomly selected patients (mean age 41 ± 15 years) were enrolled in this study. 39 patients underwent a conventional clinical assessment, dental bitewing X-ray and a dental MRI investigation comprising a conventional turbo-spin echo (TSE) and a dedicated UTE scan. One patient had to be excluded owing to claustrophobia. In four patients, the clinical treatment of the lesions was documented by intraoral pictures, and the resulting volume of the cavity after excavation was documented by dental imprints and compared with the MRI findings.

RESULTS

In total, 161 lesions were identified. 157 (97%) were visible in the UTE images, 27 (17%) in the conventional TSE images and 137 (85%) in the X-ray images. In total, 14 teeth could not be analysed by MR owing to artefacts caused by dental fillings. All lesions appear significantly larger in the UTE images as compared with the X-ray and TSE images. In situ measurements confirm the accuracy of the lesion dimensions as observed in the UTE images.

CONCLUSION

The presented data provide evidence that UTE MR imaging can be applied for the identification of caries lesions. Although the current data suggest an even higher sensitivity of UTE MRI, some limitations must be expected from dental fillings.

[Frequency of cardiac arrhythmia in patients with liver cirrhoses and evaluation of associated factors]

INTRODUCTION

Studies analysing the frequency of rhythm disorders in patients with cirrhosis are rare. Nevertheless, factors triggering rhythm disorders occur frequently in cirrhosis. Therefore, a retrospective case control study was performed investigating the frequency of cardiac arrhythmia in a population of patients with cirrhosis while evaluating several associated factors.

METHODS

The files of patients with cirrhosis (n  =  293) in the period 2004 - 2008 were analysed retrospectively regarding cardiac arrhythmia. The frequency of cardiac arrhythmia in the presence of relevant risk factors was analysed using χ ²tests and logistic regression models.

RESULTS

61.1  % of all patients were male (mean age 61.7 years) and 38.9  % female (mean age 62.8 years). The severity of cirrhosis according to the Child-Pugh score (CP) was as follows: CP A 43.3  %, CP B 32.8  % and CP C 23.9  %. Altogether, rhythm disorders were diagnosed in 16.4  % (48/293) of the study population, most frequently atrial fibrillation (68.8  %) and atrial flutter (6.7  %). An advanced age and comorbidities such as arteriosclerotic diseases, hypercholesterinemia (p  <  0.001, each) and diabetes mellitus (p  =  0.013) correlated significantly with the frequency of rhythm disorders which occurred more often in males than in females (p  = 0.066). Ongoing alcohol abuse, the severity of cirrhosis and arterial hypertension were not associated significantly with the onset of rhythm disorders. 84.4  % of all patients with cardiac arrhythmia were treated by diuretics. Decreased (<  3.5 mmol/L) and elevated (>  5 mmol/L) potassium values were observed in 60.6  % of the study collective. Rhythm disorders were more often observed in patients with hyperkalemia (especially atrioventricular block, p  < 0.01).

CONCLUSION

Compared to the average population, the prevalence of atrial fibrillation was increased in our cirrhotic cohort. The occurrence of rhythm disorders was significantly associated with arteriosclerotic diseases, hypercholesterinaemia and diabetes mellitus. Additionally, cardiac arrhythmia must be considered under diuretic therapy and in the presence of electrolyte disturbances.

Forces on cardiac implantable electronic devices during remote magnetic navigation

BACKGROUND

Remote magnetic navigation systems are used for catheter navigation in cardiac electrophysiological ablation procedures. In this setting, ferromagnetic particles will be moved by changes in the magnetic field. It is unknown to what extent cardiac implantable electronic devices (CIED) are affected by the magnetic field when using magnetic navigation, and whether these forces may exceed the limit of 5 N that is set forth by German and European norms for implanted electrodes.

METHODS

A total of 121 rhythm devices were examined in a magnetic field of 0.1 T using the NIOBE II(®) Magnetic Navigation System (Stereotaxis, St. Louis, USA). Forces acting on the devices were measured with the force measurement tool Futek LRF 400 (Futek Advanced Sensor Technology Inc., Irvine, CA, USA). A standardized protocol of different movements of the magnetic field including all three dimensions was performed and maximal forces on the CIED were assessed.

RESULTS

Out of 121 devices, 78 different pacemakers (54 different model families from 11 manufacturers) and 43 different cardioverter-defibrillators (26 different model families from 6) were examined. The mean force that could be observed was 0.33 ± 0.13 N for pacemakers (range 0.16-1.12 N) and 1.05 ± 0.11 N for cardioverter-defibrillators (range 0.86-1.38 N) when exposed to the magnetic field.

CONCLUSION

Exposure of pacemakers or implantable cardioverter-defibrillators to a magnetic field of 0.1 T does not result in a force exceeding the regulatory demanded 5 N that could damage the connected leads.