‘There Was Nothing Anybody Could Do for These Patients.’ Now There Is. 

A Swedish filmmaker’s investigative documentary raised further questions, as did a Vanity Fair article detailing how the beguiling surgeon became romantically involved with an NBC producer working on a feature about him and apparently conned her into believing he was divorced and would marry her in a ceremony officiated by the pope and attended by the Clintons, Obamas, John Legend and Elton John.

The Karolinska Institute, alleging scientific misconduct, dismissed Dr. Macchiarini, who has long denied wrongdoing. Journals retracted several of his studies. In 2019, an Italian court said he had forged documents and abused his position, charges unrelated to his trachea work. In September, a Swedish prosecutor indicted him on aggravated assault charges related to three trachea transplants. The case is pending.

Dr. Genden said Dr. Macchiarini’s rise and fall profoundly affected his own path.

“Here’s this handsome Italian surgeon at the finest institution in the world, the Karolinska, and he’s everything I’m not: He’s got a beautiful head of hair, he drives a motorcycle, he’s got an accent, he’s incredibly charismatic and dynamic,” Dr. Genden said. “He says, ‘I’ve created this bioreactor and it’s stem cells and it makes tracheas.’ And it’s huge.”

Dr. Genden said that when he and colleagues questioned Dr. Macchiarini at a conference early on, “in his bigger-than-life way he says, ‘This is ridiculous, you don’t know what you’re talking about, it functions beautifully.’”

Dr. Genden thought his work had “become obsolete, so you basically shut down the lab,” he said. “You can’t justify doing experimental surgery and immunosuppression when you see something else that looks perfect, so you realize, wow, we’re out of business.”

As Dr. Macchiarini’s work drew criticism, Dr. Genden revived his idea, but was uncertain about trying it. The scandal meant “there’s an amazing amount of scrutiny,” he said. “We’re going to show up and say, ‘As a student, I had this idea on the back of a napkin and now we’re ready to go’ — and if it fails, the patient dies and it becomes yet another example of some surgeon who thought he could solve a problem and he’s created, instead, just the opposite.”

There was another reason to be daunted too: historical assumptions that tracheas weren’t transplantable.