The relative contribution of hemodynamic parameters to blood pressure decrease in classical orthostatic hypotension.

Purpose: We studied the relative contributions of total peripheral resistance (TPR), stroke volume (SV) and heart rate (HR) to low blood pressure in classical orthostatic hypotension (cOH) on group and individual levels.

Methods: We retrospectively analyzed tilt test records from cOH patients and age/sex-matched controls. We quantified relative effects of HR, SV and TPR on mean arterial pressure (MAP) with the log-ratio method.

Study protocol for the Heads-Up trial: a phase II randomized controlled trial investigating head-up tilt sleeping to alleviate orthostatic intolerance in Parkinson's Disease and parkinsonism.

Background: In persons with Parkinson's Disease (PD) or certain forms of atypical parkinsonism, orthostatic hypotension is common and disabling, yet often underrecognized and undertreated. About half of affected individuals also exhibit supine hypertension. This common co-occurrence of both orthostatic hypotension and supine hypertension complicates pharmacological treatments as the treatment of the one can aggravate the other.

Variability of cardioinhibition in vasovagal syncope: differences between subgroups during cardioinhibition and beyond.

Purpose: We compared hemodynamic parameters between subjects with marked, intermediate and minimal cardioinhibition during vasovagal syncope.

Methods: The study included subjects with a decrease in heart rate while experiencing a complete vasovagal syncope during tilt-table testing. The subjects were classified as having marked, intermediate or minimal cardioinhibition, based on tertile values of the decrease in heart rate.

Syncope Diagnosis at Referral to a Tertiary Syncope Unit: An in-Depth Analysis of the FAST II.

Objective: A substantial number of patients with a transient loss of consciousness (T-LOC) are referred to a tertiary syncope unit without a diagnosis. This study investigates the final diagnoses reached in patients who, on referral, were undiagnosed or inaccurately diagnosed in secondary care.

Methods: This study is an in-depth analysis of the recently published Fainting Assessment Study II, a prospective cohort study in a tertiary syncope unit.

Influence of Age on Magnitude and Timing of Vasodepression and Cardioinhibition in Tilt-Induced Vasovagal Syncope.

Background: Cardioinhibition may diminish with age, but the changing balance of cardioinhibition and vasodepression with age has not been quantified, leaving the mechanism of vasovagal syncope (VVS) in old age unclear.

Objectives: This study sought to quantify age-related changes of vasodepression and cardioinhibition in tilt-induced VVS.

Methods: We studied 163 cases of tilt-induced VVS, evoked using the Italian protocol with blood pressure, heart rate, and video-electroencephalographic monitoring.

The pathophysiology of vasovagal syncope: Novel insights.

The pathophysiology of vasovagal syncope (VVS) is reviewed, focusing on hemodynamic aspects. Much more is known about orthostatic than about emotional VVS, probably because the former can be studied using a tilt table test (TTT). Recent advances made it possible to quantify the relative contributions of the three factors that control blood pressure: heart rate (HR), stroke volume (SV) and total peripheral resistance (TPR).

Novel Methods for Quantification of Vasodepression and Cardioinhibition During Tilt-Induced Vasovagal Syncope.

Rationale: Assessing the relative contributions of cardioinhibition and vasodepression to the blood pressure (BP) decrease in tilt-induced vasovagal syncope requires methods that reflect BP physiology accurately.

Objective: To assess the relative contributions of cardioinhibition and vasodepression to tilt-induced vasovagal syncope using novel methods.

Methods And Results: We studied the parameters determining BP, that is, stroke volume (SV), heart rate (HR), and total peripheral resistance (TPR), in 163 patients with tilt-induced vasovagal syncope documented by continuous ECG and video EEG monitoring.

Timing of Circulatory and Neurological Events in Syncope.

Syncope usually lasts less than a minute, in which short time arterial blood pressure temporarily falls enough to decrease brain perfusion so much that loss of consciousness ensues. Blood pressure decreases quickest when the heart suddenly stops pumping, which happens in arrhythmia and in severe cardioinhibitory reflex syncope. Loss of consciousness starts about 8 s after the last heart beat and circulatory standstill occurs after 10-15 s.

Measurements of medial temporal lobe atrophy for prediction of Alzheimer's disease in subjects with mild cognitive impairment.

Our aim was to compare the predictive accuracy of 4 different medial temporal lobe measurements for Alzheimer's disease (AD) in subjects with mild cognitive impairment (MCI). Manual hippocampal measurement, automated atlas-based hippocampal measurement, a visual rating scale (MTA-score), and lateral ventricle measurement were compared. Predictive accuracy for AD 2 years after baseline was assessed by receiver operating characteristics analyses with area under the curve as outcome.

Prediction of Alzheimer disease in subjects with amnestic and nonamnestic MCI.

Objective: To compare the predictive accuracy of β-amyloid (Aβ)1-42 and total tau in CSF, hippocampal volume (HCV), and APOE genotype for Alzheimer disease (AD)-type dementia in subjects with amnestic mild cognitive impairment (aMCI) and nonamnestic mild cognitive impairment (naMCI).

Methods: We selected 399 subjects with aMCI and 226 subjects with naMCI from a multicenter memory clinic-based cohort. We measured CSF Aβ1-42 and tau by ELISA (n = 231), HCV on MRI (n = 388), and APOE ε4 (n = 523).

Injury markers predict time to dementia in subjects with MCI and amyloid pathology.

Objectives: Alzheimer disease (AD) can now be diagnosed in subjects with mild cognitive impairment (MCI) using biomarkers. However, little is known about the rate of decline in those subjects. In this cohort study, we aimed to assess the conversion rate to dementia and identify prognostic markers in subjects with MCI and evidence of amyloid pathology.

Injury markers but not amyloid markers are associated with rapid progression from mild cognitive impairment to dementia in Alzheimer's disease.

Alzheimer's disease (AD) is a common cause of mild cognitive impairment (MCI). However, the time between the diagnosis of MCI and the diagnosis of dementia is highly variable. In this study we investigated which known risk factors and biomarkers of AD pathology were associated with rapid progression from MCI to dementia.

[Unexceptional symptoms as expression of MELAS].

An 11-year-old girl and a 25-year-old woman were both initially referred to a neurologist with 'common' neurological problems: The girl suffered from tics, and later epilepsy, and her serum lactate concentration was elevated. She had unilateral hyperintensity of the left cerebral cortex and later developed diabetes mellitus. The woman had muscle weakness, diabetes mellitus and ptosis.

Biomarkers as predictors for conversion from mild cognitive impairment to Alzheimer-type dementia: implications for trial design.

Disease modifying drugs for Alzheimer's disease (AD) are likely to be most effective when given in non-demented subjects. In this review we summarized biomarkers in cerebrospinal fluid (CSF) and blood that can predict AD-type dementia in subjects with mild cognitive impairment (MCI). In addition, we investigated whether these markers could reduce sample size and costs if used to select subjects for trials on the prevention of AD in subjects with MCI.