Origins of medical innovation: the case of coronary artery stents.

BACKGROUND

Innovative medical devices make major contributions to patient welfare, and coronary stents have been among the most important device developments of recent decades. However, the origins of such breakthrough medical technologies remain poorly understood.

METHODS AND RESULTS

Using a comprehensive database of patents, we identified all individuals and institutions that developed intellectual property related to stent technology early in its development process. The patents were categorized and described using a predetermined qualitative coding strategy. We found 245 granted patents related to bare metal coronary artery stents from 1984 (when the first patent issued in this field) to 1994 (after the first stents were approved). Each year showed an increase in the number of patent filings: from 1 in 1984 to 97 in 1994. The largest fraction of patents was issued to private entities (44.9% of the total). Public companies, individual inventors, and nonprofit institutions represented 31.4%, 18.0%, and 5.7%, respectively. The top 10 most-cited patents in the field were dominated by 2 private entities, Expandable Grafts Partnership and Cook Inc, organizations created by or dependent on the work of independent academic physician-inventors.

CONCLUSIONS

Coronary artery stent technology first arose from individual physician-inventors within academic medical centers and their associated private companies. After these initial innovations were in place, the field became dominated by large public companies. This history suggests that policies aimed at encouraging transformative medical device development would have their greatest effect if focused on individual inventors and scientists performing the early stages of technology development.