Abstract 15094: Prevalence of Coronary Microvascular Dysfunction in Women With Angina and No Obstructive Coronary Artery Disease: Preliminary Results From the iPower Study
Bibliographic record
Abstract
Background: Women are more often than men found to have no obstructive coronary artery disease (CAD) when evaluated with a coronary angiogram (CAG) due to angina pectoris and suspected ischemic heart disease. Coronary microvessel dysfunction (CMD) is a possible explanation, and can be assessed by transthoracic Doppler echocardiography (TTDE) with measurement of coronary flow reserve (CFR). Reduced CFR carries an adverse prognosis despite absence of obstructive CAD. The aim of the ongoing iPower study is to evaluate CFR in women with angina pectoris and no obstructive CAD. Methods: Women with angina pectoris and a CAG without obstructive coronary artery disease (>50%) are systematically invited to participate. Assessment includes demographic and clinical data, blood samples and TTE during rest and high-dose dipyridamole stress (0.84mg/kg) with measurement of CFR by Doppler of the left anterior descending artery. Results: To date (May 21st 2014) 3500 women have been screened (flowchart), 793 women have been included (response rate 23%). Mean age was 62.4 (+/-9.6) and the burden of risk factors was relatively high (Table 1). CFR was successfully measured in 763 patients (96%). Median (IQR) CFR was 2.4 (2.0-2.8). Cut-off point for CMD of both 2 and 2.5 has been used previously. In this population, 214 (28%) had a CFR≤2 and 468 (61%) a CFR≤2.5. Conclusions: To our knowledge, iPower is the largest and most comprehensive study systematically assessing CMD in women with angina pectoris and no obstructive CAD. Non-invasive CFR assessment is feasible, and microvascular function impaired in a large proportion. Future follow-up will determine the prognostic value of CFR as a measure of CMD.
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 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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".