Cardiac pacing in severe recurrent reflex syncope and tilt-induced asystole

Aim

The benefit of cardiac pacing in patients with severe recurrent reflex syncope and asystole induced by tilt testing has not been established. The usefulness of tilt-table test to select candidates for cardiac pacing is controversial.

Methods and results

We randomly assigned patients aged 40 years or older who had at least two episodes of unpredictable severe reflex syncope during the last year and a tilt-induced syncope with an asystolic pause longer than 3 s, to receive either an active (pacing ON; 63 patients) or an inactive (pacing OFF; 64 patients) dual-chamber pacemaker with closed loop stimulation (CLS). The primary endpoint was the time to first recurrence of syncope. Patients and independent outcome assessors were blinded to the assigned treatment. After a median follow-up of 11.2 months, syncope occurred in significantly fewer patients in the pacing group than in the control group [10 (16%) vs. 34 (53%); hazard ratio, 0.23; P = 0.00005]. The estimated syncope recurrence rate at 1 year was 19% (pacing) and 53% (control) and at 2 years, 22% (pacing) and 68% (control). A combined endpoint of syncope or presyncope occurred in significantly fewer patients in the pacing group [23 (37%) vs. 40 (63%); hazard ratio, 0.44; P = 0.002]. Minor device-related adverse events were reported in five patients (4%).

Conclusion

In patients aged 40 years or older, affected by severe recurrent reflex syncope and tilt-induced asystole, dual-chamber pacemaker with CLS is highly effective in reducing the recurrences of syncope. Our findings support the inclusion of tilt testing as a useful method to select candidates for cardiac pacing.

Study registration

ClinicalTrials.gov identifier NCT02324920, Eudamed number CIV-05-013546.

Benefit of dual-chamber pacing with Closed Loop Stimulation in tilt-induced cardio-inhibitory reflex syncope (BIOSync trial): study protocol for a randomized controlled trial

Background

The efficacy of dual-chamber cardiac pacing in neuro-mediated reflex syncope with a cardio-inhibitory response to the Tilt-Table test (TT) has not been definitively assessed so far. The lack of reproducibility of results from previous studies may be partially explained by discrepancies in subject selection and some weaknesses in design and methods. The European Society of Cardiology (ESC) has set a class IIb indication to pacemaker implantation in this population recommending further research.

Methods/design

The BIOSync study is a multicenter, patient- and outcome-assessor-blind, randomized, parallel-arm, placebo-controlled trial with the objective of assessing the clinical benefit of cardiac pacing in patients with frequently recurrent reflex syncope, suspected (but not proven) to be triggered by asystolic pauses as showing a VASIS 2B response to the TT (>3-s pause regardless of blood pressure drop). The primary and secondary endpoints are time to first post-implantation recurrence of syncope or the combination of pre-syncope or syncope, respectively. One hundred and twenty-eight consenting patients will be 1:1 randomized to dual-chamber cardiac pacing ‘on’ or ‘off’ after pacemaker implantation, and followed up until the first adjudicated primary endpoint event for a maximum of 2 years. The so-called Closed Loop Stimulation function on top of dual-chamber pacing is the pacing mode selected in the study active arm. Participating patients are asked to self-report syncopal symptoms at least every 3 months with self-administered questionnaires addressed to an independent Adjudication Committee. Patients and members of the Adjudicating Committee are blinded to randomization. The study is designed to detect a 40% relative reduction in the 2-year incidence of syncopal recurrences with 80% statistical power.

Discussion

The BIOSync study is designed to definitively assess the benefit of pacing against placebo in reflex syncope patients with a cardio-inhibitory response to the TT. The study will also provide important information on the efficiency of the TT in appropriately selecting reflex syncope patients for cardiac pacing.

Trial registration

ClinicalTrials.gov, identifier: NCT02324920 (27 October 2016, date last accessed).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-1941-4) contains supplementary material, which is available to authorized users.

Oxygen–iron interaction in liquid lead–bismuth eutectic alloy

Iron released in steel corrosion is a key impurity in reactions with dissolved oxygen in liquid lead–bismuth eutectic alloys.

Electrophysiological registration of phonological perception in the subthalamic nucleus of patients with Parkinson's Disease

Phonological processing is usually associated with the activation of cortical areas, especially in the left cerebral hemisphere. This study examined if phonologically elicited evoked potentials can be recorded directly from the subthalamic nucleus in patients with Parkinson's Disease (PD). Seven PD patients who had undergone implantation of deep brain electrodes for the stimulation of the subthalamic nucleus were included. Local field potentials were recorded in a pre-attentive auditory phonological task, an attentive auditory phonological discrimination task, and a word recognition task. Auditory evoked potentials related to phonological, but not lexical processing, could be demonstrated in the subthalamic nucleus for all three tasks. Only minor changes were found after levodopa administration. This study demonstrates that the subthalamic nucleus is involved in early phonological perception, which puts the subthalamic nucleus in a position to modify phonological perception in a larger cortico-subcortical network.

Antihypertensive effectiveness of aliskiren for the 'real-world' management of hypertension: multilevel modelling of 180-day blood pressure outcomes (the Belgian DRIVER Study)

AIMS

The 'DRIVER' study was designed to investigate the 'real-world' effectiveness of aliskiren-based treatment of hypertension. This article reports the 180-day blood pressure (BP) outcomes, and the multilevel (physician- and patient-level) determinants thereof.

METHODS AND RESULTS

DRIVER was a prospective, observational, open-label, multi-centre, pharmaco-epidemiologic study of hypertensive patients treated with aliskiren in whom prior treatment failed or was not tolerated. 2070 patients (enrolled by 426 physicians) were enrolled; 1695 patients (81.9%) completed the 180-day aliskiren treatment period. Mean patient age was 64.2 ± 12.1 years; 53.7% were men, 25.3% diabetic and 40.7% had a high or very high cardiovascular (CV) risk. At 180 days, the mean ± SD reductions in systolic and diastolic BP were -22.9 ± 16.7 mmHg and -10.5 ± 10.9 mmHg respectively (both p < .001). 2007 and 2009 guideline-defined BP control was achieved in 36.4% and 56.3% of patients, respectively (both p < .001). 64.2% of eligible patients had a reduction in CV risk (p < .001). A physician-level class effect was responsible for 22.8% and 28.1% of variability in systolic and diastolic BP, respectively, for 20.1% of variability in BP control, and for 16.1% of variability in the reduction of CV risk. Both patient- (e.g. adherence) and physician-related factors (e.g. age and knowledge) were significant in profiling best response to treatment with aliskiren. Adverse events reported in this article were consistent with the aliskiren scientific leaflet.

CONCLUSION

Aliskiren is safe and effective in reducing BP, improving BP control and reducing global CV risk in a 'real-world' setting and for patients in whom prior treatment failed or was not tolerated. Optimising treatment adherence and strategic medical education may be ways of improving BP outcomes in patients with hypertension.

Tuberculosis and tuberculosis control in European prisons

OBJECTIVE

Correctional facilities have often been cited as reservoirs for tuberculosis (TB), presenting a potential threat to the general population. Although correctional facilities are recognised as ideal settings for interventions, little is known about the TB epidemiology within them. The purpose of our survey was to collect data on TB in prisons of the WHO European Region and on existing control measures.

DESIGN

A questionnaire was sent to 52 EuroTB correspondents asking for 2002 data on the total number of inmates, number of prisoners with TB, resistance rates, screening strategies, monitoring and responsibilities.

RESULTS

Twenty-two (42.3%) countries completed the questionnaire. The median TB notification rate was 232 per 100,000 inmates (0-17,808). Prisoners had up to 83.6 times more TB than civilians. The majority (90.9%) of the participating countries reported performing active screening for TB on entry into prison, with a median detection rate of 393/100,000 (42-2362). Of the respondent countries, 81.8% claimed to perform contact investigations and 86.4% to house infectious TB patients separately.

CONCLUSION

Although response to this survey was only 42.3% and might be biased by a country's engagement in TB control in prisons, the results highlight the vulnerability of prisoners to TB and emphasise the need for adequate case-finding and containment strategies in prison.

The genome of black cottonwood, Populus trichocarpa (Torr. & Gray)

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

Fast separations on monolithic silica columns: method transfer, robustness and column ageing for some case studies

Six separation methods, developed on conventional silica high performance liquid chromatography (HPLC) columns were transferred to monolithic silica columns of 5 and 10 cm length. The transferred methods include the separation of an alkylbenzene mixture, the separations of drugs from their impurities (nimesulide, tetracycline, phenoxymethylpenicillin and erythromycin) and the separation of a green tea extract. The transfer of the first three methods was successful while for the latter three it was not. Increasing the flow rate up to 9 ml/min (where possible) inversely decreased the analysis time of the successfully transferred methods to 48 s (alkylbenzene mixture) 1.8 min (nimesulide mixture) and 3 min (tetracycline mixture) while still reasonable well separated peaks were obtained. The robustness and repeatability of the transferred and accelerated separations was found to be acceptable. Despite the use of flow rates up to 9 ml/min and frequent mobile phase changes with pH values varying from 3.5 to 7, the column performance was found to be rather constant and the column ageing to be minimal.

Chronic radiodermatitis following percutaneous coronary interventions: a report of two cases

We describe two patients in whom chronic radiodermatitis with therapy-resistant ulceration of the right scapular region developed, following percutaneous coronary intervention with fluoroscopic imaging. Contrary to most reported cases in the literature, which involve numerous cardiac catheterization procedures, in both patients described here the total radiation dose was given during two successive procedures, involving difficult and prolonged coronary intervention with stent implantation. In both cases, local treatment of the ulcerative lesions was insufficient, necessitating excision of the radiodermatitis area and replacement with a skin graft, with good therapeutic result. The incidence of radiodermatitis after percutaneous coronary interventions is rising with the increasing number and complexity of these procedures. The main risk factor is a long duration of fluoroscopy using the same incidence. The skin lesions encompass a wide spectrum, ranging from erythema, telangiectasia, atrophy, hyperpigmentation and hypopigmentation to necrosis, chronic ulceration and squamous cell carcinoma. The lesions can appear from 15 days to 10 years after the procedure. To prevent radiation-induced injury, the radiation dose has to be limited and monitored. Also, careful inspection of the skin at the site of exposure is necessary and the radiographic beam has to be restricted to the smallest field size. A good clinical follow-up at regular intervals is important after long and complicated procedures.

Pulmonary tuberculosis in prisons of the ex-USSR state Georgia: results of a nation-wide prevalence survey among sentenced inmates

SETTING

The penitentiary system of the ex-USSR state of Georgia.

OBJECTIVES

To measure the prevalence of active pulmonary tuberculosis and drug-resistant disease among prisoners. To identify factors associated with active tuberculosis and multidrug resistance (MDR).

DESIGN

A comprehensive multiphasic screening survey for tuberculosis.

RESULTS

The prevalence of smear- or culture-positive tuberculosis was 5995 per 100,000 prisoners (n = 448 cases among 7473 inmates). Of all the strains, 215 (77.9%) were resistant to at least one drug and 37 (13.0%) were MDR. Independent risk markers associated smear- or culture-positive tuberculosis with included prison stay of 2 years or more, body mass index <20 kg/m2, accommodation in a large size prison, previous anti-tuberculosis treatment, cough of 2 weeks or more and loss of appetite. Risk markers associated with MDR were a prison stay of less than 2 years and being over 25 years of age.

CONCLUSIONS

In Georgia, the excess risk for tuberculosis among prisoners is unprecedented, suggesting that prisons represent a significant reservoir of tuberculosis. Only a comprehensive strategy for tuberculosis control in prisons, including prison reform, control of anti-tuberculosis drugs, and prompt and efficient diagnosis and treatment of patients can have an impact on the tuberculosis burden in the prison system.

Venous pooling during nitrate-stimulated tilt testing in patients with vasovagal syncope

AIMS

To investigate the importance of venous pooling and variation in venous tone during nitrate-stimulated tilt testing in patients.

METHODS

Ten patients with a history of vasovagal syncope underwent an upright tilt test after an injection of 99mTc-labelled albumin. A gamma camera was positioned at the level of the lower legs. The patients were tilted to 90 degrees for 30 min or until symptoms developed. In those subjects who did not show any symptoms before the end of the 30-min period, isosorbide dinitrate (ISDN) 5 mg was given sublingually and the test was prolonged for a maximum of 15 min.

RESULTS

Nine of 10 patients needed nitrate stimulation to develop symptoms, and one patient remained symptom free following ISDN administration. Measurement of radioactivity revealed no significant increase in calf volume after nitrate stimulation (the mean volume increase was 77% before ISDN stimulation and a further 0.9% afterwards).

CONCLUSIONS

The higher sensitivity for vasovagal syncope during upright tilt testing after administration of sublingual ISDN is not due to an increase in venous pooling in the lower extremities.

Sublingual nitrates during head-up tilt testing for the diagnosis of vasovagal syncope

Pharmacologic stimulation during head-up tilt test (HUT) is used to increase the diagnostic yield of the test to detect vasovagal syncope. Reported lack of specificity of stimulation with intravenous isoproterenol has made a pharmacologic alternative desirable. Because nitrates are known to cause syncope of a vasovagal origin, we administered sublingual nitrates after classic tilt test in 32 patients with a history of typical vasovagal syncope and 20 healthy volunteers to assess the sensitivity, specificity, and accuracy of this new HUT technique. During the classic HUT four (13%) patients had syncope; after administration of sublingual nitrates, this number increased to 28 (87%). In the control group no subject had syncope during classic HUT, whereas during nitrate administration six (30%) had syncope. Sublingual nitrate stimulated HUT revealed a maximum accuracy of 83% at a cutoff point of 11 minutes, giving a sensitivity of 81% and specificity of 85%. Sublingual nitrate administration increased the accuracy of HUT in diagnosing vasovagal syncope in patients with a history of typical vasovagal syncope.

[Treatment of menopausal hot flushes with a nonhormonal medication, veralipride]

The value of veralipride in menopausal disorders is no longer questionable and has been documented by a number of studies. The purpose of this paper is to study the clinical effectiveness and to look for the biological consequences of three months therapy with veralipride. To achieve this, a thorough biological study (hematology, glucids, lipids, hepatic and renal function) was done in 21 patients with a menopausal syndrome before and after taking veralipride for three months. Clinical effectiveness was excellent with 80% satisfactory results. No signs of intolerance or adverse side-effects were seen. We recorded no significant changes in biological parameters. No disturbances of renal or hepatic function were detected, either in individual assessments or in the overall statistical analysis of the study group. Because it is well tolerated, effective, and devoid of adverse metabolic side-effects, we conclude that veralipride is the best non-hormonal treatment for menopausal disorders presently available.