Ronald Buyl

Inferior and Lateral Electrocardiographic Repolarization Abnormalities in Brugada Syndrome

Background—Repolarization abnormalities in the inferior-lateral leads in Brugada syndrome (BS) have not been systematically investigated. Methods and Results—280 patients (age, 41±18 years; 168 males) with BS were screened for inferior-lateral repolarization abnormalities. The repolarization abnormalities were classified either as early repolarization pattern or coved ≥2-mm Brugada pattern and as spontaneous or class I antiarrhythmic drug (AAD) induced. Thirty-two patients (11%) had inferior-lateral spontaneous early repolarization pattern. These patients were less likely to be asymptomatic at first presentation (13 of 32 versus 156 of 248 patients, P=0.02), and spontaneous type I ECG was more frequent among them (38% versus 21%, P=0.05). The spontaneous early repolarization pattern occurred more frequently among patients with BS than in 283 family members not having BS (11% versus 6%, P=0.03). Class I AAD administration provoked inferior-lateral coved Brugada pattern in 13 patients with BS. These patients had longer baseline PR intervals (206±48 versus 172±31 ms, P<0.001) and class I AAD–induced QRS interval prolongation (108 to 178 versus 102 ms to 131 ms, P<0.001). In 3 patients, the class I AAD–provoked coved Brugada pattern was only present in the inferior leads. Conclusions—Inferior-lateral early repolarization pattern occurs spontaneously relatively frequently in BS. These patients have a more severe phenotype. Class I AAD administration provokes inferior-lateral coved Brugada pattern in 4.6% of patients. We report for the first time 3 patients in whom the class I AAD–provoked coved Brugada pattern was only observed in the inferior leads.

Ultrasound elastography as an objective diagnostic measurement tool for lymphoedema of the treated breast in breast cancer patients following breast conserving surgery and radiotherapy

Background. Lymphoedema of the operated and irradiated breast is a common complication following early breast cancer treatment. There is no consensus on objective diagnostic criteria and standard measurement tools. This study investigates the use of ultrasound elastography as an objective quantitative measurement tool for the diagnosis of parenchymal breast oedema. Patients and methods. The elasticity ratio of the subcutis, measured with ultrasound elastography, was compared with high-frequency ultrasound parameters and subjective symptoms in twenty patients, bilaterally, prior to and following breast conserving surgery and breast irradiation. Results. Elasticity ratio of the subcutis of the operated breast following radiation therapy increased in 88.9% of patients, was significantly higher than prior to surgery, unlike the non operated breast and significantly higher than the non operated breast, unlike preoperative results. These results were significantly correlated with visibility of the echogenic line, measured with high-frequency ultrasound. Big preoperative bra cup size was a significant risk factor for the development of breast oedema. Conclusions. Ultrasound elastography is an objective quantitative measurement tool for the diagnosis of parenchymal breast oedema, in combination with other objective diagnostic criteria. Further research with longer follow-up and more patients is necessary to confirm our findings.

A novel pacing manoeuvre to diagnose atrial tachycardia.

AIMS Currently used diagnostic manoeuvres at the electrophysiology study do not always allow for consistent identification of atrial tachycardia (AT), either because of inapplicability of the technique or because of low predictive value and specificity. The aim of this study was to determine whether overdrive atrial pacing during paroxysmal supraventricular tachycardia (SVT) with the same cycle length from both the high right atrium and the coronary sinus can accurately identify or exclude AT by examining the difference between the V-A intervals of the first returning beat of tachycardia between the two pacing sites. METHODS AND RESULTS Fifty-two patients were included; 24 patients with atrioventricular nodal re-entry tachycardia (AVNRT), 13 patients with atrioventricular re-entry tachycardia (AVRT), and 15 patients with AT. Comparing the 37 non-AT patients with the 15 AT patients, there was a highly significant difference between the mean V-A interval difference, (delta V-A) 2.1 +/- 1.8 ms (range 0-9 ms) vs. 79.1 +/- 42 (range 22-267 ms) (P < 0.001), respectively. None of the patients in the non-AT group had a delta V-A > 10 ms. In contrast, all 15 patients with AT had a delta V-A interval >10 ms. Thus, the diagnostic accuracy of the delta V-A interval cut-off of >10 ms was 100%, with a 95% confidence interval of 93.1-100% for AT. In 11 (73%) of the 15 AT patients, the standard ventricular overdrive pacing manoeuvre was not possible. In 14 of the 15 patients (93%) in the AT group, standard atrial overdrive pacing showed variable V-A intervals, correctly diagnosing AT. In all 52 patients, this measurement was repeated during pacing from the other location. In five patients from the AT group, the result of the second attempt was different from the result of the first attempt. CONCLUSION We found that atrial differential pacing during paroxysmal SVT without termination of tachycardia and the finding of variable returning V-A interval was highly sensitive and specific for the diagnosis of AT. The manoeuvre can be easily performed in all patients with SVT and is highly reproducible. It is a useful adjunct to the currently available ventricular and atrial pacing manoeuvres.

A refugee camp in the centre of Europe: clinical characteristics of asylum seekers arriving in Brussels

Background In the summer of 2015, the exodus of Syrian war refugees and saturation of refugee camps in neighbouring countries led to the influx of asylum-seekers in European countries, including Belgium. This study aims to describe the demographic and clinical characteristics of asylum seekers who arrived in a huddled refugee camp, in the centre of a well-developed country with all medical facilities. Methods Using a descriptive cross-sectional study design, physicians of Médecins du Monde prospectively registered age, gender, origin, medical symptoms and diagnoses of all patients presenting to an erected field hospital in Brussels in September 2015. Diagnoses were post hoc categorised according to the International Classification of Diseases. Results Of 4037 patients examined in the field hospital, 3907 were included and analysed for this study. Over 11% of patients suffered from injuries, but these were outnumbered by the proportion of patients with respiratory (36%), dental (9%), skin (9%) and digestive (8%) diagnoses. More than 49% had features of infections at the time of the consultation. Conclusions Asylum seekers arriving in a refugee camp in Brussels after a long and hazardous journey suffer mostly from respiratory, dental, skin and digestive diseases. Still, one in seven suffers from injury. These findings, consistent with other reports, should be anticipated when composing emergency medical teams and interagency emergency health or similar kits to be used in a field hospital, even in a Western European country. Trial registration number ISRCTN13523620, Results.

The Impact of Accelerated Right Prefrontal High-Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) on Cue-Reactivity: An fMRI Study on Craving in Recently Detoxified Alcohol-Dependent Patients

In alcohol-dependent patients craving is a difficult-to-treat phenomenon. It has been suggested that high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) may have beneficial effects. However, exactly how this application exerts its effect on the underlying craving neurocircuit is currently unclear. In an effort to induce alcohol craving and to maximize detection of HF-rTMS effects to cue-induced alcohol craving, patients were exposed to a block and event-related alcohol cue-reactivity paradigm while being scanned with fMRI. Hence, we assessed the effect of right dorsolateral prefrontal cortex (DLPFC) stimulation on cue-induced and general alcohol craving, and the related craving neurocircuit. Twenty-six recently detoxified alcohol-dependent patients were included. First, we evaluated the impact of one sham-controlled stimulation session. Second, we examined the effect of accelerated right DLPFC HF-rTMS treatment: here patients received 15 sessions in an open label accelerated design, spread over 4 consecutive days. General craving significantly decreased after 15 active HF-rTMS sessions. However, cue-induced alcohol craving was not altered. Our brain imaging results did not show that the cue-exposure affected the underlying craving neurocircuit after both one and fifteen active HF-rTMS sessions. Yet, brain activation changes after one and 15 HF-rTMS sessions, respectively, were observed in regions associated with the extended reward system and the default mode network, but only during the presentation of the event-related paradigm. Our findings indicate that accelerated HF-rTMS applied to the right DLPFC does not manifestly affect the craving neurocircuit during an alcohol-related cue-exposure, but instead it may influence the attentional network.

Anatomic predictors of phrenic nerve injury in the setting of pulmonary vein isolation using the 28-mm second-generation cryoballoon

BACKGROUND Phrenic nerve injury (PNI) is the most frequently observed complication during pulmonary vein (PV) isolation using the second-generation cryoballoon. OBJECTIVE The purpose of this study was to analyze anatomic predictors based on preprocedural computed tomographic imaging data. METHODS Forty-one patients with PNI during the procedure and 123 age-, gender-, and body mass index-matched controls were included. A total of 343 right PVs were evaluated for axial/coronal orientation, ostial diameters with cross-sectional area, ovality index, and branching pattern. External angle between the right superior pulmonary vein (RSPV) and the anterolateral wall of the left atrium (LA) was measured (RSPV-LA angle). Distance from this vertex to the superior vena cava (SVC) was considered the RSPV-SVC distance. RESULTS For the RSPV, more anterosuperior orientation, larger dimensions, shorter RSPV-SVC distance, and more obtuse RSPV-LA angle (all P <.001) were associated with PNI on univariate analysis. Independent variables after multivariable analysis were RSPV-LA angle (odds ratio 1.03 per degree, 95% confidence interval 1.01-1.04, P <.001) and RSPV area (odds ratio 1.2 per mm², 95% confidence interval 1.1-1.3, P <.001), with a cutoff value ≥141° for RSPV-LA angle (91% sensitivity, 85% specificity) and ≥275 mm² for RSPV area (88% sensitivity, 85% specificity). RIPV area was an independent predictor for PNI at RIPV. A right-sided long common trunk was seen exclusively in 3 patients in the PNI group. CONCLUSION Preprocedural anatomic assessment of right PVs is useful in evaluating the risk of PNI. Ostial vein area and external RSPV-LA angle measurement showed excellent predictive value for PNI at the RSPV.

Spinal cord stimulation modulates cerebral neurobiology: A proton magnetic resonance spectroscopy study

IntroductionAlthough spinal cord stimulation (SCS) is a widely used treatment for chronic neuropathic pain secondary to spinal surgery, little is known about the underlying physiological mechanisms.MethodsThe primary aim of this study is to investigate the neural substrate underlying short-term SCS by means of 1H MR spectroscopy with short echo time, in 20 patients with failed back surgery syndrome.ResultsMarked increase of γ-aminobutyric acid (GABA) and decrease in glucose in the ipsilateral thalamus were found between baseline situation without SCS and after 9′ of SCS, indicating the key role of the ipsilateral thalamus as a mediator of chronic neuropathic pain. In addition, this study also showed a progressive decrease in glucose in the ipsilateral thalamus over time, which is in line with the findings of previous studies reporting deactivation in the ipsilateral thalamic region.ConclusionsThe observation of GABA increase and glucose decrease over time in the ipsilateral thalamus may be the causal mechanism of the pain relief due to SCS or an epiphenomenon.

Trunk kinematics during walking in persons with multiple sclerosis: The influence of body weight support

BACKGROUND Although body weight supported (BWS) treadmill training (TT) leads to some improvements in walking ability, it has not been proven that it is more effective than other walking therapies in persons with multiple sclerosis (PwMS). One possible explanation could be that BWSTT focuses on the cyclic movement of the lower extremities while the trunk is passively suspended in the harness. OBJECTIVE This study aimed to assess the 3 dimensional trunk and pelvis movements during BWS treadmill walking. METHODS 14 PwMS and 14 healthy persons (8 male/20 female; age 23 to 59 years) walked with 0%, 10%, 20%, 30%, 50% and 70% BWS. After a familiarization period, kinematic electromagnetic tracking (Polhemus Liberty™ 240/16) of the trunk and pelvis movements was applied. Statistical analysis consisted of a repeated measures ANOVA with simple contrasts (SPSS 20). RESULTS This study shows that BWS walking leads in general to smaller maximum trunk and pelvis movement amplitudes compared with walking without BWS, this with exception of the pelvis anterior-posterior movement in healthy subjects. CONCLUSION These data help to identify and isolate the effect of different BWS levels in PwMS and in healthy persons and suggest to use BWS lower than 30% for treadmill training.

Influence of Botulinum Toxin Therapy on Postural Control and Lower Limb Intersegmental Coordination in Children with Spastic Cerebral Palsy

Botulinum toxin injections may significantly improve lower limb kinematics in gait of children with spastic forms of cerebral palsy. Here we aimed to analyze the effect of lower limb botulinum toxin injections on trunk postural control and lower limb intralimb (intersegmental) coordination in children with spastic diplegia or spastic hemiplegia (GMFCS I or II). We recorded tridimensional trunk kinematics and thigh, shank and foot elevation angles in fourteen 3–12 year-old children with spastic diplegia and 14 with spastic hemiplegia while walking either barefoot or with ankle-foot orthoses (AFO) before and after botulinum toxin infiltration according to a management protocol. We found significantly greater trunk excursions in the transverse plane (barefoot condition) and in the frontal plane (AFO condition). Intralimb coordination showed significant differences only in the barefoot condition, suggesting that reducing the degrees of freedom may limit the emergence of selective coordination. Minimal relative phase analysis showed differences between the groups (diplegia and hemiplegia) but there were no significant alterations unless the children wore AFO. We conclude that botulinum toxin injection in lower limb spastic muscles leads to changes in motor planning, including through interference with trunk stability, but a combination of therapies (orthoses and physical therapy) is needed in order to learn new motor strategies.

Breathing retraining in patients with chronic fatigue syndrome: A pilot study

The study aimed to 1) examine the point prevalence of asynchronous breathing in chronic fatigue syndrome (CFS) patients; 2) examine whether CFS patients with an asynchronous breathing pattern present with diminished lung function in comparison with CFS patients with a synchronous breathing pattern; and 3) examine whether one session of breathing retraining in CFS patients with an asynchronous breathing pattern is able to improve lung function. Twenty patients fulfilling the diagnostic criteria for CFS were recruited for participation in a pilot controlled clinical trial with repeated measures. Patients presenting with an asynchronous breathing pattern were given 20–30 minutes of breathing retraining. Patients presenting with a synchronous breathing pattern entered the control group and received no intervention. Of the 20 enrolled patients with CFS, 15 presented with a synchronous breathing pattern and the remaining 5 patients (25%) with an asynchronous breathing pattern. Baseline comparison revealed no group differences in demographic features, symptom severity, respiratory muscle strength, or pulmonary function testing data (spirometry). In comparison to no treatment, the session of breathing retraining resulted in an acute (immediately postintervention) decrease in respiratory rate (p<0.001) and an increase in tidal volume (p<0.001). No other respiratory variables responded to the session of breathing retraining. In conclusion, the present study provides preliminary evidence supportive of an asynchronous breathing pattern in a subgroup of CFS patients, and breathing retraining might be useful for improving tidal volume and respiratory rate in CFS patients presenting with an asynchronous breathing motion.