Clinton underwent a procedure called angioplasty, the hospital said, in which a balloon catheter is threaded through an artery to the blocked vessel in the heart.

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They ended up producing a flexible catheter tube that goes a bit of the way up the nostrils, then a guide wire is inserted into the targeted sinus. (In live patients this is done via an endoscope and fluoroscope.) A balloon catheter is advanced over the guide wire and positioned against the blocked ostium.

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Each year, doctors in America perform about a million angioplasty procedures, using a balloon-tipped catheter to open clogged arteries and relieve chest pain.

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It is compressed, along with a balloon, into an 8 millimeter catheter that is threaded up from an incision in the groin into the heart.

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The modern device era exploded in 1977 with the invention of angioplasty, when German cardiologist Andreas Gruentzig made a tiny slice near the hip of a patient and inserted a catheter tipped with a balloon into an artery.

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The original catheter-based treatment balloon angioplasty is still used hundreds of thousands of times each year in the U.S. alone.

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Stents are used in angioplasty, a procedure in which a balloon is inserted into a heart artery via a catheter and used to reopen it, alleviating chest pain, allowing patients to walk and treating heart attacks.

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Using general anesthesia, the surgeon threaded a catheter up her nose, expanded a tiny balloon and cleared a permanent space for her sinuses to drain.

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