Effects of Autonomic Blockade on Heart Rate Variability after Spinal Cord Injury: A Case Series
Bibliographic record
Abstract
The purpose of this study was to examine the effects of pharmacological cardiac autonomic blockade on heart rate variability (HRV) in individuals with SCI and compare these effects to age, sex, and weight-matched able-bodied controls. Three males (45.8 years) with incomplete tetraplegia and three male (33.0 years) able-bodied controls underwent 10 min of electrocardiogram recordings before and after beta-blockade (metoprolol tartrate) and cholinergic blockade (atropine sulphate), in both the 0 deg−tilt position and during cardiovascular stress (40 deg head-up tilt, cold pressor, and isometric jaw contraction). The cardiac response to such blockade was determined using power spectral analysis. In the three participants with SCI, atropine sulphate was associated with a 99.9, 98.2, and 99.2% reduction in resting high-frequency (HF) power, while metoprolol tartrate was associated with a 72.5, 73.1, and 39.6% decrease in the low-frequency to high-frequency ratio (LF:HF) during cardiovascular stress. Similar changes were experienced by the able-bodied participants. HF power is a valid estimate of cardiac parasympathetic outflow, and cardiac sympathovagal balance contributes to the LF:HF ratio in individuals with SCI. Large-scale studies on the validity of HRV after SCI are warranted, since such measures may gauge autonomic impairment and subsequent improvement.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.003 | 0.026 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.005 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.002 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".