In January, a nine-year-old girl in Singapore underwent surgery for a complex congenital heart condition.
But it was no usual operation.
Before entering the operating room, the two doctors had the girl's heart printed out in 3D form, in "real size".
That way, they got "a good feel" for what they were in for during the surgery, said Dr Chen Ching Kit of KK Women's and Children's Hospital's (KKH) cardiology service, who performed the diagnosis and imaging for the patient.
The procedure was successful.
Looking ahead, printing 3D hearts looks set to become more common here, as doctors harness the cutting-edge technology to help them in complicated surgical procedures.
Another patient, whose operation using 3D printing technology has yet to be scheduled, is an infant with the rare condition of a double- outlet left ventricle, which causes low blood oxygen levels.
Printing the heart takes around two hours and involves running the images from a patient's magnetic resonance imaging scan through software processing. This produces a 3D image of the heart, which is fed into the printer to produce the rubber-like 3D heart.
Yesterday, the doctors said the 3D printing technology is especially useful for operating on complex congenital heart conditions - and in particular those involving young children.
Dr Chen said the usual ways of using 2D imaging technology for simpler congenital heart conditions are adequate, but more complex cases stand to benefit from 3D heart models. "The heart is a moving structure... so 2D imaging methods often lack critical spatial information."
While 3D printing is already being used by hospitals here for reconstructive surgery for the skull for post-trauma injury, cancer surgery, or congenital conditions, it has only recently been successfully deployed for heart operations.
The KKH doctors were unable to say if the January procedure was the first one in Singapore using a 3D-printed heart model.
Elsewhere in the world, hospitals have also started doing so, with those in the United States using the technology as early as last year.
The models come in handy especially for complex congenital heart cases (for example, where the heart is short of one chamber, or there are two inlets leading into the chamber), which make up 1 to 2 per cent of the 200-odd congenital heart operations performed at the cardiac centre at KKH each year, said Dr Nakao Masakazu, a consultant at the cardiothoracic surgery service at KKH, who was the operating surgeon.
Children have much smaller hearts than adults due to their smaller chest cavities and, together with the complexity of certain congenital heart defects, makes congenital heart surgery more challenging compared with adult heart surgery.
In addition, a lack of paediatric cardiac specimens here, unlike in countries such as the US and Britain, means that these 3D-printed hearts are also useful for learning purposes and developing implantable devices.
Printing the heart takes around two hours and involves running the images from a patient's magnetic resonance imaging scan through software processing.
This produces a 3D image of the heart, which is fed into the printer to produce the rubber-like 3D heart.
However, cost may be a discouraging factor, with each 3D-printed heart costing anywhere from $2,000 to $3,000.
The hospital is working with two companies - Materialise and Creatz3D - to print the hearts, but is looking into building its own 3D printing facility.