It's a big and very active business. In 2009 alone, doctors implanted ~225,000 pacemakers in the US: https://www.ncbi.nlm.nih.gov/pubmed/21707667 https://www.n

It's a big and very active business. In 2009 alone, doctors implanted ~225,000 pacemakers in the US: https://www.ncbi.nlm.nih.gov/pubmed/21707667 https://www.ncbi.nlm.nih.gov/pubmed/21707667 Germany had the highest reported rate of new implants for any country in the study, at almost 1/1000 just in 2009. In the US that would be 300,000 per year just in new devices, and based on the study's aggregate reporting we could guess another 1/3 for replacement devices - 400,000 new devices per year as a high guess. There's probably better info in the article but I don't have journal access and don't want to spend $6 to get it for this article.