Using a precise 3D-printed replica of his heart, surgeons at Cleveland Clinic Children's planned and performed a ventricular switch on four-year-old Wyatt Keller, who was born with a rare criss-cross heart. The 3D model let the team study Wyatt's unique anatomy before surgery, helping map a complex repair. After the January 2026 operation, Wyatt recovered fully, resumed normal activities and is not expected to need further procedures.
Four-Year-Old With Rare 'Criss-Cross' Heart Undergoes Life-Changing Surgery Planned With 3D-Printed Replica
Wyatt Keller, 4, has a rare condition called criss-cross heart. (Cleveland Clinic Children's via SWNS)
A four-year-old boy born with a rare heart arrangement known as a "criss-cross" heart has had a transformative operation planned using a 3D-printed replica of his own heart. Wyatt Keller of Cleveland, Ohio, underwent the procedure in January 2026 at Cleveland Clinic Children's to restore more normal blood flow and energy levels.
What Is a Criss-Cross Heart?
Criss-cross heart refers to an uncommon congenital arrangement in which the connections between the heart's upper (atria) and lower (ventricles) chambers are twisted, so the atrioventricular valves and ventricles sit in a crossed or stacked alignment rather than side by side. In some children this causes few symptoms, but in many cases it occurs alongside other defects that eventually require surgical correction.
Criss-cross heart refers to the atrioventricular valves being positioned in an abnormal crossed pattern, with two ventricles positioned one above the other – rather than being side by side. (Cleveland Clinic Children's via SWNS)
How 3D Printing Helped Plan the Operation
Specialists at Cleveland Clinic Children's created a detailed 3D-printed model of Wyatt's heart from his medical imaging. The replica allowed the surgical team to study his unique anatomy before entering the operating room and to map out a precise surgical strategy for the complex repair.
The Procedure
Hani Najm, MD, Chair of Pediatric and Congenital Heart Surgery at Cleveland Clinic Children's, performed the operation in January 2026 using a technique he developed called a ventricular switch. The procedure rebuilt internal pathways in Wyatt's heart to reroute blood flow so both lower chambers could contribute to pumping effectively.
Wyatt Keller's heart scan. (Cleveland Clinic Children's via SWNS)
"The 3D-printed model was a replica of Wyatt's heart, so even before stepping into the operating room, I could see the anatomy and determine exactly how I want to do the repair," Dr. Najm said.
Recovery and Outlook
Wyatt recovered well after surgery, was gradually cleared of all physical restrictions, and has returned to riding his bike, playing T-ball and keeping pace with his brothers. Physicians currently do not expect he will need additional procedures, though he will remain under ongoing follow-up with his medical team.
Family Perspective
Wyatt's mother, Anna Keller, said: "Wyatt is still the same joyful little boy he's always been—now with the energy of a typical four-year-old." His father, Jonathon Keller, added: "It was a blessing we had the right team, the right tools and everything we could have hoped and prayed for to get Wyatt and our family through this."
Reporting by Cleveland Clinic Children's. Procedure performed January 2026.
Help us improve.
