Nonsurround, nonuniform, biventricular-capable direct cardiac compression provides Frank-Starling recruitment independent of left ventricular septal damage
Bibliographic record
Abstract
OBJECTIVES: Right ventricular (RV) function is compromised in 25% of left ventricular (LV) assist device recipients despite effective LV support. The risk of such dysfunction has been enhanced by an ischemic or undamaged interventricular septum; however, we found septal infarction to be paradoxically protective. We, therefore, evaluated the potential of nonsurround, nonuniform, biventricular-capable direct cardiac compression (DCC) (using the HeartPatch DCC) to overcome RV dysfunction in hearts with a normal or infarcted interventricular septum. METHODS: Ethanol ablation was used to create an interventricular septal infarction in 6 sheep, and 6 others served as the control sheep. The load-independent and in-series RV response to DCC was assessed using sonomicrometer heart dimension sensors. Triphenyltetrazolium perfusion delineated the septal damage. RESULTS: LV DCC caused a greater increase of the RV preload recruitable stroke work in the control sheep than in the study sheep (190.6 ± 23.5 and 135.0 ± 40.8 erg*10^3, respectively, P < .001). In contrast, RV end-systolic elastance increased more in the septal-ablated sheep with RV DCC (17.29 ± 3.40 vs 9.88 ± 2.01 mm Hg/mL in the control sheep, P < .001). Abnormal RV diastolic function before device insertion in the septal-ablated sheep was normalized with both passive DCC placement and after activation (RV diastolic relaxation constant 23.5 ± 2.3 and 20.0 ± 2.1 ms, respectively, P < .001). Both biventricular and RV DCC actuation increased the RV systolic pressure more in the septal-ablated sheep than in the control sheep (37.9 ± 6.3 and 47.7 ± 4.6 mm Hg vs 29.7% ± 4.8% and 40.3% ± 8.3%, respectively, P < .001). In contrast, the RV end-systolic diameter decreased more during LV DCC (70.1% ± 15.9% vs 90.5% ± 5.0%, P < .001). CONCLUSIONS: The HeartPatch DCC support of LV and RV function results from improvement of the systolic septal-lateral fractional change that is not influenced by septal infarction. The latter attenuated LV to RV device energy delivery during LV patch actuation but enhanced RV energy delivery during RV patch actuation. This DCC technique can provide effective support in high-risk RV failure situations arising from left ventricular assist device use.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".