Design and use of a quantitative scale for measuring presyncope

Impact of bundle branch block morphology on outcomes of patients with syncope and bifascicular block: A SPRITELY (POST 3) substudy

BACKGROUND

Permanent pacing is often considered for patients with syncope and bifascicular block.

OBJECTIVE

The purpose of this study was to determine whether QRS morphology or other electrocardiographic characteristics can identify patients who may benefit from permanent pacing.

METHODS

The Syncope: Pacing or Recording in the Later Years (SPRITELY) trial was a multicenter trial that randomized patients with bifascicular block and syncope (n = 115) to empiric pacemaker implantation vs implantable loop recorder (ILR) monitoring. In this SPRITELY subanalysis, baseline 12-lead electrocardiograms were evaluated for bundle branch block (BBB) morphology, QRS width, and PR and QT intervals and their impact on clinical outcomes was assessed.

RESULTS

There were 41 patients with left BBB (36%), 69 patients with right bundle branch block (RBBB) and left anterior fascicular block (60%), and 5 patients with RBBB and left posterior fascicular block (4%). Pacemaker implant compared with ILR was associated with a significant reduction of major study-related events (MSREs) in both patients with left BBB (23.8% vs 78.9%; P = .001) and those with RBBB (27% vs 72.9%; P < .0001). Similarly, a reduction of MSREs was observed in both patients with trifascicular block (23% vs 84.6%; P < .0001) and those with bifascicular block (26.6% vs 68.9%; P = .002). In the group randomized to ILR monitoring, the type of BBB was not a predictor of recurrent syncope (P = .30), bradycardia requiring pacemaker (P = .15), or MSREs (P = .42). The presence of PR interval prolongation or QRS width in this group did not predict MSREs (P = .22 and P = .96, respectively).

CONCLUSION

In patients with syncope and bifascicular block, pacemaker implantation reduces adverse events as compared with ILR monitoring, irrespective of the type of BBB or the presence of PR interval prolongation.

Lessons learned from the pilot study of an orthostatic hypotension intervention in the subacute phase following spinal cord injury

Context: Following spinal cord injury (SCI) at the cervical or upper-thoracic level, orthostatic hypotension (OH) is observed in 13-100% of patients. This study aimed to test the feasibility of conducting a randomized controlled trial combining a dynamic tilt-table (Erigo^®) and functional electrical stimulation (FES) to mitigate OH symptoms in the subacute phase after SCI. Design: Pilot study. Setting: A tertiary rehabilitation hospital. Participants: Inpatients who had a C4-T6 SCI (AIS A-D) less than 12 weeks before recruitment, and reported symptoms of OH in their medical chart. Interventions: Screening sit-up test to determine eligibility, then 1 assessment session and 3 intervention sessions with Erigo^® and FES for eligible participants. Outcome measures: Recruitment rate, duration of assessment and interventions, resources used, blood pressure, and Calgary Presyncope Form (OH symptoms). Results: Amongst the 232 admissions, 148 inpatient charts were reviewed, 11 inpatients met all inclusion criteria, 7 participated in a screening sit-up test, and 2 exhibited OH. Neither of the two participants recruited in the pilot study was able to fully complete the assessment and intervention sessions due to scheduling issues (i.e. limited available time). Conclusion: This pilot study evidenced the non-feasibility of the clinical trial as originally designed, due to the low recruitment rate and the lack of available time for research in participant's weekday schedule. OH in the subacute phase after SCI was less prevalent and less incapacitating than expected. Conventional management and spontaneous resolution of symptoms appeared sufficient to mitigate OH in most patients with subacute SCI.

Exercise and the multidisciplinary holistic approach to adolescent dysautonomia

AIM

To determine whether an eight-week strength training programme as part of a multidisciplinary approach would minimise symptoms and improve quality of life in patients with dysautonomia.

METHODS

Adolescents referred to a tertiary-level cardiology service from May 2014-December 2015 with symptoms of dysautonomia were eligible. Participants completed an exercise test and a quality of life (QoL) questionnaire (PedsQL) prior to the intervention. Participants were asked to complete exercises five times per week. After eight weeks, participants returned for follow-up testing. Parents completed a proxy report of their child's QoL at both time points.

RESULTS

A total of 17 participants completed the study protocol with an adherence rate of up to 50%. Post-intervention, QoL scores improved across all levels in the participants [total 65.2 (50.4-74.7) vs 48.9 (37.5-63.0); p = 0.006; psychosocial 65.8 (56.1-74.6) vs 50.0 (41.7-65.8); p = 0.010; physical 62.5 (37.5-76.6) vs 43.8 (25-68.5); p = 0.007] and their parent proxy reports [total 63.5 (48.7-81.3) vs 50.0 (39.3-63.0); p = 0.004; psychosocial 62.1 (52.1-81.3) vs 50.0 (39.6-59.2); p = 0.001; physical 62.5 (51.6-80.0) vs 50.0 (27.5-70.3); p = 0.003]. Treadmill time also improved (9.1 vs 8.0 minutes; p = 0.005).

CONCLUSION

Following an eight-week strength training programme, dysautonomia patients report a significant improvement in both their quality of life and endurance time.

TiTrATE: A Novel, Evidence-Based Approach to Diagnosing Acute Dizziness and Vertigo

Diagnosing dizziness can be challenging, and the consequences of missing dangerous causes, such as stroke, can be substantial. Most physicians use a diagnostic paradigm developed more than 40 years ago that focuses on the type of dizziness, but this approach is flawed. This article proposes a new paradigm based on symptom timing, triggers, and targeted bedside eye examinations (TiTrATE). Patients fall into 1 of 4 major syndrome categories, each with its own differential diagnosis and set of targeted examination techniques that help make a specific diagnosis. Following an evidence-based approach could help reduce the frequency of misdiagnosis of serious causes of dizziness. In the spirit of the flipped classroom, the editors of this Neurologic Clinics issue on emergency neuro-otology have assembled a collection of unknown cases to be accessed electronically in multimedia format. By design, cases are not linked with specific articles, to avoid untoward cueing effects for the learner. The cases are real and are meant to demonstrate and reinforce lessons provided in this and subsequent articles. In addition to pertinent elements of medical history, cases include videos of key examination findings.

Rationale for the Assessment of Metoprolol in the Prevention of Vasovagal Syncope in Aging Subjects Trial (POST5)

BACKGROUND

Vasovagal syncope (VVS) is a common problem associated with a poor quality of life, which improves when syncope frequency is reduced. Effective pharmacological therapies for VVS are lacking. Metoprolol is a β-adrenergic receptor antagonist that is ineffective in younger patients, but may benefit older (≥40 years) VVS patients. Given the limited therapeutic options, a placebo-controlled clinical trial of metoprolol for the prevention of VVS in older patients is needed.

STRUCTURE OF STUDY

The POST5 is a multicenter, international, randomized, placebo-controlled study of metoprolol in the prevention of VVS in patients ≥40 years old. The primary endpoint is the time to first recurrence of syncope. Patients will be randomized 1:1 to receive metoprolol 25 to 100 mg BID or matching placebo, and followed up for 1 year. Secondary end points include syncope frequency, presyncope, quality of life, and cost analysis. Primary analysis will be intention to treat, with a secondary on-treatment analysis.

POWER CALCULATIONS

A sample size of 222, split equally between the groups achieves 85% power to detect a hazard rate of 0.3561 when the event rates are 50% and 30% in the placebo and metoprolol arms. Allowing for 10% dropout, we propose to enroll 248 patients.

IMPLICATIONS

This study will be the first adequately powered trial to determine whether metoprolol is effective in preventing VVS in patients ≥40 years. If effective, metoprolol may become the first line pharmacological therapy for these patients.

Ischaemic stroke or TIA in older subjects associated with impaired dynamic blood pressure control in the absence of severe large artery stenosis

BACKGROUND

older subjects may require higher baseline blood pressures to maintain cerebral perfusion. We investigated whether episodic hypotension is associated with tissue infarction in subjects with syncopal symptoms at stroke onset.

METHODS

over 30 months, all acute strokes/TIAs were prospectively screened for symptoms of syncope or presyncope at stroke onset. Subjects with severe large vessel stenosis were excluded, while cases were referred for syncope unit investigation. All underwent 1.5 T MRI acutely, and suspected borderzone infarctions (BZI) were confirmed through Matlab-derived perfusion software. Case-control comparison was derived from stroke controls with no prior syncope history.

RESULTS

thirty-eight of 772 stroke patients described presyncope or syncope at stroke onset and had patent large vessels (4.9% of all strokes). Median age was 72 years (IQR 21.4). Twenty-two patients (58%) were prescribed antihypertensive agents at symptom onset. Twenty-six (68.4%) reported focal neurology <24 h in duration. 63.2% (n = 24) of cases reported prior syncope history, compared with 33% (N = 103) of controls, P < 0.001. Cases exhibited greater orthostatic BP drop than controls, P < 0.05 Twenty-four patients were diagnosed with vasovagal syncope through head-up tilt symptom reproduction, 9 with orthostatic hypotension, 4 with cardiac syncope and 1 with carotid sinus syndrome. Nineteen (50%) patients had an acute infarct on MRI, 14 of these were in the arterial borderzone (73.6%). The BZI group were significantly older than the non-BZI group, 79.2 yrs versus 63.3 yrs, P = 0.002.

CONCLUSION

subjects reporting hypotensive symptoms at stroke onset have a higher prevalence of borderzone infarction, despite being normotensive or hypertensive at baseline.

Rationale for the prevention of syncope trial IV: assessment of midodrine

BACKGROUND

Vasovagal syncope is a common problem associated with a poor quality of life, which improves when the frequency of syncope is reduced. Effective pharmacological therapies for vasovagal syncope have been elusive. Midodrine is a pro-drug whose primary metabolite is an alpha-1 adrenoreceptor agonist. A few studies have suggested that it may be beneficial in syncope, but all have had significant methodological limitations. A placebo-controlled clinical trial of midodrine for the prevention of vasovagal syncope is needed.

STRUCTURE OF STUDY

The prevention of syncope trial IV (POST 4) is a multicenter, international, randomized, placebo-controlled study of midodrine in the prevention of vasovagal syncope. The primary end point is the time to first recurrence of syncope. Patients will be randomized 1:1 to receive midodrine 10-30 mg/day or matching placebo, and followed for 1 year. Secondary end points include syncope frequency, presyncope, and quality of life. Primary analysis will be performed with an intention-to-treat approach, with a secondary on-treatment analysis.

POWER CALCULATIONS

A total sample size of 112, split equally between the two groups, achieves 85 % power to detect a 50 % relative risk reduction when the event rates are 55 and 27.5 % in the placebo and midodrine arms. Allowing for 20 % dropout, we propose to enroll 140 patients.

REGISTRATION

POST 4 is registered with http://www.clinicaltrials.gov (NCT01456481).

IMPLICATIONS

This study will be the first adequately powered trial to determine whether midodrine is effective in preventing vasovagal syncope. If it is effective, then midodrine may become the first-line pharmacological therapy for this condition.

Syncope and near-syncope as a multifactorial problem in geriatric inpatients: Systemic hypotension is an underrated predictor for syncope exclusively

PURPOSE

Syncope (SC) and near-syncope (NS) are still misunderstood syndromes. Aim of study was to determine the risk factors for SC, NS, as well as for both entities (SC/NS) in geriatric inpatients reporting these events within the last year, irrespectively of the reason of admission to hospital.

MATERIAL AND METHODS

The retrospective study covered 250 patients, consecutively admitted to the geriatric ward. Patients were assigned to the three models: SC and/or NS in total, n=106; isolated NS, n=72; SC with co-existing NS, if any, n=34, and compared with patients without any such events (n=144). The patients underwent a comprehensive geriatric assessment and complete clinical investigation. The binary logistic regression was applied to predict risk factors for each of the models.

RESULTS

Falls were most predictive for NS model (OR 35.4; 95% CI 10.3-121.1), and systemic hypotension for SC model (OR 92.9; 95% CI 6.1-1421.0). The highest specificity (85%) and sensitivity (81%) were found for the SC/NS model, with the highest contribution by falls (OR 18.1; 95% CI, 7.6-45.2), orthostatic hypotension (OR 8.1; 95% CI, 3.5-18.5), a history of stroke or transient ischemic attack, treatment with an angiotensin receptor blocker, plasma creatinine >1.4mg/dL, negatively self-rated health, vertigo, pathology of carotid arteries, and lack of hypertension.

CONCLUSIONS

Syncope and near-syncope in geriatric inpatients have multifactorial and cumulative aetiology, with blurred, frequently overlapping boundaries between them. The falls, postural hypotension, and/or brain hypoperfusion of different origin seem to be most predictive of the both events, however low systemic blood pressure was predictive for the syncope exclusively.

The risk for syncope and presyncope during surgery in surgeons and nurses

BACKGROUND

Surgeons and nurses are exposed to orthostatic stress.

AIMS

To assess the lifetime incidence of syncopal and presyncopal events during surgery in operation room staff and reveal the predicting factors.

METHODS AND RESULTS

The study included 317 subjects (161 F, 156 M) aged 43.9 ± 9.6; 216 surgeons and 101 instrumenters. The study included filling of an anonymous questionnaire on the syncope and presyncope history.

RESULTS

At least one syncopal event during operation was reported by 4.7% and presyncope by 14.8% of the studied population. All but one subject reported prodromal symptoms before syncope. In the medical history, syncope outside the operating room was reported by 11% of the studied group. Syncope and presyncope during operation was related to syncope in the medical history outside the operation room, respectively: odds ratio (OR) 20.2 95% confidence interval (CI): 2.0-70.5 and OR 10.8; CI: 5.0-23.4 and to presyncope in the medical history, respectively: OR 23.5; CI: 7.4-74.4 OR 8.9; CI: 3.6-11.2 (P < 0.001).

CONCLUSIONS

(1) Syncope and presyncope may occur during surgery in the staff of the operating room. (2) Syncope in the operating room is usually preceded by prodromal symptoms and has vasovagal origin. (3) Both lower then expected occurrence of syncope in the operating room staff and absence of any difference between genders in this regard indicate preselection in the process of choosing profession and specialization. (4) Syncope and presyncope outside the operating room in medical history increases the risk of syncope and presyncope inside the operation room.