Is Cerebral Microembolism in Prosthetic Heart Valves Clinically Relevant?
Bibliographic record
Abstract
P138 Background. High intensity transient signals (HITS) are frequently detected by TCD ultrasound in patients with mechanical PHV, but the published data about their clinical relevance is controversial. This study was undertaken to determine whether the presence of HITS is related to clinical and neuropsychological changes in patients with mechanical PHV. Methods. Patients with mechanical PHV had bilateral 30 minute TCD monitoring for microemboli (HITS) detection with and without oxygen (O 2 ) inhalation. Cognitive testing of patients included MMSE, DRS, and Microcog with two measures: General Cognitive Performance (GCP) and General Cognitive Functioning (GCF). Results. We studied 36 patients (20 females, mean age 58±13 years), 20 with mitral, 9 with aortic, and 7 with a combined PHV after median of 1.5 years of valve insertion. HITS were detected in 72% of patients. There was no difference in HITS frequency between 16 symptomatic and 20 asymptomatic patients. HITS counts were significantly decreased after O 2 inhalation (21.7±30.6 vs. 3.3±9.1 s, p=0.009 ). Table shows that no relationship exists between the number of HITS and cognitive scores of patients. Conclusion. Decreased frequency of HITS after oxygen inhalation confirms their gaseous origin. Lack of relationship between the HITS and cognitive performance suggests that cerebral microembolism in PHV is a benign epiphenomenon without any clinical neurological and neuropsychological sequalae.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 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 source (direct Gemma or distilled Codex), 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".