Paper
In cardiovascular trials, the key problem is not scarcity. It is a large, still-muted registry record.
How quiet is the older cardiovascular trial record in ClinicalTrials.gov once heart and vascular studies are grouped into one registry-first family? We analysed 26,062 eligible older cardiovascular studies from the March 29, 2026 full-registry snapshot, spanning coronary, stroke, heart-failure, rhythm, and vascular records. Primary comparisons tracked two-year no-results rates, ghost protocols, sponsor-class mix, phase patterns, and the sponsors holding the biggest unresolved stock. Across older cardiovascular studies, 75.0 percent lacked posted results and 39.3 percent showed neither results nor a linked publication trail. PHASE1 remained the largest phase bucket, while Assistance Publique - Hôpitaux de Paris carried the biggest named sponsor stock at 144 older missing-results studies in the cardiovascular family. The cardiovascular record is therefore not just incomplete. It remains structurally quiet across common phases despite its central place in evidence-based medicine. This matters for guideline-facing cardiovascular medicine. These family-level estimates measure registry-visible absence rather than legal culpability or publication quality within this cardiovascular frame.