“Diagnosing abnormal end-diastolic forward flow: New definition proposal based on healthy controls”

Introduction: Precise analysis of aortic hemodynamics is crucial in the study of bicuspid aortic valve (BAV) disease. This study provides a comprehensive evaluation of aortic forward flow (FF), reverse flow (RF) and stasis in BAV patients using novel 3D-based techniques previously shown to be more accurate than traditional 2D analysis methods. Hypothesis: BAV patients without valve dysfunction show abnormal aortic FF, RF, and stasis compared to healthy controls. Methods: We recruited 44 BAV patients (48±15 yrs, 27% female) and 23 healthy controls (37±14 yrs, 35% female). Cardiac MRI at 3T was performed inclusive of 4D-flow imaging. Patients with any aortic stenosis (AS) or ≥mild regurgitation (AR) were excluded. Flow analysis was performed by segmented volumetric regions: left ventricular outflow tract (LVOT), ascending aorta (AAo), arch, proximal descending aorta (PDAo), and distal descending aorta (DDAo). In each region, forward flow (FF), reverse flow (RF) and stasis were averaged over the cardiac cycle on a voxel-by-voxel basis. Left ventricular (LV) end-diastolic volume, end-systolic volume and ejection fraction were also measured. T-tests (or non-parametric equivalent) compared differences in parameters between cohorts. Results: BAV patients were significantly older than controls (48±15 vs. 37±14 yrs; p=0.01) but exhibited no significant differences in LV measures. Patients showed reduced FF in the AAo (0.09±0.03 vs. 0.11±0.04 mL/cycle; p<0.01), but greater FF in all downstream regions (eg. PDA: 0.02±0.03 vs. 0.01±0.02 mL/cycle; p=0.01). RF was significantly elevated in patients in the AAo (0.06±0.02 vs. 0.02±0.02 mL/cycle; p<0.01). BAV patients exhibited significantly less stasis in every region except the DDAo (eg. AAo: 23±11 vs. 50±10 % of cardiac cycle). Conclusions: 3D-derived measurements of FF, RF, and stasis are significantly altered in the thoracic aorta of BAV patients in the absence of AS or AR.

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Hemodynamic Assessment in Bicuspid Aortic Valve Disease and Aortic Dilation: New Insights From Voxel-By-Voxel Analysis of Reverse Flow, Stasis, and Energetics

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.725113 ◽

2022 ◽

Vol 9 ◽

Author(s):

Patrick Geeraert ◽

Fatemehsadat Jamalidinan ◽

Fiona Burns ◽

Kelly Jarvis ◽

Michael S. Bristow ◽

...

Keyword(s):

Peak Velocity ◽

Reverse Flow ◽

Aortic Surgery ◽

Healthy Controls ◽

Aortic Dilation ◽

4D Flow Mri ◽

4D Flow ◽

Descending Aorta ◽

Forward Flow ◽

Flow Mri

Objectives: Clinical management decisions surrounding ascending aorta (AAo) dilation in bicuspid aortic valve (BAV) disease benefit from personalized predictive tools. 4D-flow MRI may provide patient-specific markers reflective of BAV-associated aortopathy. This study aims to explore novel 4D-flow MRI parametric voxel-by-voxel forward flow, reverse flow, kinetic energy and stasis in BAV disease. We hypothesize that novel parametric voxel-by-voxel markers will be associated with aortic dilation and referral for surgery and can enhance our understanding of BAV hemodynamics beyond standard metrics.Methods: A total of 96 subjects (73 BAV patients, 23 healthy controls) underwent MRI scan. Healthy controls had no known cardiovascular disease. Patients were clinically referred for AAo dilation assessment. Indexed diameters were obtained by dividing the aortic diameter by the patient’s body surface area. Patients were followed for the occurrence of aortic surgery. 4D-flow analysis was performed by a single observer in five regions: left ventricular outflow tract (LVOT), AAo, arch, proximal descending aorta (PDAo), and distal descending aorta (DDAo). In each region peak velocity, kinetic energy (KE), forward flow (FF), reverse flow (RF), and stasis were measured on a voxel-by-voxel basis. T-tests (or non-parametric equivalent) compared flow parameters between cohorts. Univariate and multivariate analyses explored associations between diameter and parametric voxel-by-voxel parameters.Results: Compared to controls, BAV patients showed reduced stasis (p < 0.01) and increased RF and FF (p < 0.01) throughout the aorta, and KE remained similar. In the AAo, indexed diameter correlated with age (R = 0.326, p = 0.01), FF (R = −0.648, p < 0.001), RF (R = −0.441, p < 0.001), and stasis (R = −0.288, p < 0.05). In multivariate analysis, FF showed a significant inverse association with AAo indexed diameter, independent of age. During a median 179 ± 180 days of follow-up, 23 patients (32%) required aortic surgery. Compared to patients not requiring surgery, they showed increased KE and peak velocity in the proximal aorta (p < 0.01), accompanied by increased RF and reduced stasis throughout the entire aorta (p < 0.01).Conclusion: Novel voxel-by-voxel reverse flow and stasis were altered in BAV patients and are associated with aortic dilation and surgical treatment.

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Automated Acoustic Analysis of Oral Diadochokinesis to Assess Bulbar Motor Involvement in Amyotrophic Lateral Sclerosis

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-19-00178 ◽

2020 ◽

Vol 63 (1) ◽

pp. 59-73 ◽

Cited By ~ 3

Author(s):

Panying Rong

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Acoustic Analysis ◽

Speaking Rate ◽

Disease Stage ◽

Healthy Controls ◽

Tongue Movement ◽

Major Barrier ◽

Syllable Repetition ◽

Oral Diadochokinesis ◽

Lateral Sclerosis

Purpose The purpose of this article was to validate a novel acoustic analysis of oral diadochokinesis (DDK) in assessing bulbar motor involvement in amyotrophic lateral sclerosis (ALS). Method An automated acoustic DDK analysis was developed, which filtered out the voice features and extracted the envelope of the acoustic waveform reflecting the temporal pattern of syllable repetitions during an oral DDK task (i.e., repetitions of /tɑ/ at the maximum rate on 1 breath). Cycle-to-cycle temporal variability (cTV) of envelope fluctuations and syllable repetition rate (sylRate) were derived from the envelope and validated against 2 kinematic measures, which are tongue movement jitter (movJitter) and alternating tongue movement rate (AMR) during the DDK task, in 16 individuals with bulbar ALS and 18 healthy controls. After the validation, cTV, sylRate, movJitter, and AMR, along with an established clinical speech measure, that is, speaking rate (SR), were compared in their ability to (a) differentiate individuals with ALS from healthy controls and (b) detect early-stage bulbar declines in ALS. Results cTV and sylRate were significantly correlated with movJitter and AMR, respectively, across individuals with ALS and healthy controls, confirming the validity of the acoustic DDK analysis in extracting the temporal DDK pattern. Among all the acoustic and kinematic DDK measures, cTV showed the highest diagnostic accuracy (i.e., 0.87) with 80% sensitivity and 94% specificity in differentiating individuals with ALS from healthy controls, which outperformed the SR measure. Moreover, cTV showed a large increase during the early disease stage, which preceded the decline of SR. Conclusions This study provided preliminary validation of a novel automated acoustic DDK analysis in extracting a useful measure, namely, cTV, for early detection of bulbar ALS. This analysis overcame a major barrier in the existing acoustic DDK analysis, which is continuous voicing between syllables that interferes with syllable structures. This approach has potential clinical applications as a novel bulbar assessment.

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Heart Rate Variability, Emotions, and Music

Journal of Psychophysiology ◽

10.1027/0269-8803/a000021 ◽

2010 ◽

Vol 24 (2) ◽

pp. 112-119 ◽

Cited By ~ 9

Author(s):

F. Riganello ◽

A. Candelieri ◽

M. Quintieri ◽

G. Dolce

Keyword(s):

Data Mining ◽

Heart Rate ◽

Heart Rate Variability ◽

Vegetative State ◽

Low Frequency ◽

Emotional Reactions ◽

Heart Beat ◽

Healthy Controls ◽

Frequency Spectra ◽

Emotional Value

The purpose of the study was to identify significant changes in heart rate variability (an emerging descriptor of emotional conditions; HRV) concomitant to complex auditory stimuli with emotional value (music). In healthy controls, traumatic brain injured (TBI) patients, and subjects in the vegetative state (VS) the heart beat was continuously recorded while the subjects were passively listening to each of four music samples of different authorship. The heart rate (parametric and nonparametric) frequency spectra were computed and the spectra descriptors were processed by data-mining procedures. Data-mining sorted the nu_lf (normalized parameter unit of the spectrum low frequency range) as the significant descriptor by which the healthy controls, TBI patients, and VS subjects’ HRV responses to music could be clustered in classes matching those defined by the controls and TBI patients’ subjective reports. These findings promote the potential for HRV to reflect complex emotional stimuli and suggest that residual emotional reactions continue to occur in VS. HRV descriptors and data-mining appear applicable in brain function research in the absence of consciousness.

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