Boston Scientific Corporation BSX

The business

Boston Scientific sells single-use devices that go inside people and get thrown away afterward: stents, catheters, scopes, spinal cord stimulators. About a third of revenue is MedSurg: endoscopy, urology and neuromodulation, which grow mid single digits in almost any weather. The rest is Cardiovascular, holding the two franchises that produced the last three years. Farapulse is a catheter that uses electrical pulses instead of heat to ablate the tissue causing atrial fibrillation. Watchman is a plug for the left atrial appendage that lets an AFib patient stop taking blood thinners. Both treat the same arrhythmia, and together they were 26% of last quarter's sales.

The moat is the cath lab. An electrophysiologist trained on a catheter, in a hospital that stocked the console and consumables, does not switch for a marginal edge. That holds until competitors arrive with a comparable tool and a sales force, and in pulsed field ablation three of them did.