3D Hearts: Medicine's Next Big Thing?

3D Hearts: Medicine's Next Big Thing?

CREATED Oct 17, 2013

STANFORD, Calif. (Ivanhoe Newswire) - Stents, balloons, artificial valves; there are more life-saving heart devices than ever, but a new discovery is taking cardiovascular innovations to the next level. Now, scientists have created a 3D heart that's one-of-a-kind.

Every year, half a million Americans will have some type of heart surgery.

Researchers at Stanford University are printing 3D models that are an exact replica of a patient's heart.

"If you look at the complexity and the detail of what we have, it's extraordinary," Paul J. Wang, MD, Professor of Medicine, Stanford Hospital & Clinics, told Ivanhoe.

First, they take CT images and load them onto a computer. A software program converts the data into layers. The printer then creates the heart out of hot plastic.

"So, the printer is just printing layer by layer to build up a 3D solid," Jeff Caves, Postdoctoral Research Fellow, Stanford University, told Ivanhoe.

The 3D heart could allow doctors to fit devices like catheters, stents, and valves to the exact dimensions of a patient's heart. Surgeons could also test different options in advance, making procedures safer for patients.

"When you can actually put a device inside the heart and see how it behaves, that gives you another set of confidence that it's likely to work in a human," Dr. Wang said.

It's an innovation that could change the game when it comes to heart care.

"I've never seen anything like this," Dr. Wang said.

Dr. Wang said there is other research going on using 3D printing, combined with living cells and other biological material. The goal is to one day print functioning human organs.


BACKGROUND: Heart surgeries are performed daily in the U.S. to help correct heart complications. Heart surgery may be performed on children and adults and can be life-saving to those who need replaced or repaired heart valves, repaired damaged heart structures, heart transplants, and implanted medical devices to support blood flow or control heartbeat. One of the most common performed heart surgeries is coronary artery bypass grafting. Cardiac procedures are evolving in such ways that procedures can be done with small incisions among the ribs rather than cutting through a patient's breast bone. (Source:http://www.nhlbi.nih.gov/health/health-topics/topics/hs/)

SYMPTOMS: After surgery you may experience one or more of these symptoms, but don't worry, this is expected and will take time to go away. Symptoms include:

  • Fever or chills              •     Abdominal pain
  • Chest pain                   •     Increased heart rate
  • Red stool                     •     Numbness in arms or legs
  • Headache                   •     Nausea, vomiting, or diarrhea
  • Skin rash                     •     Coughing up blood
  • Fatigue                        •     Loss of appetite

(Source: http://www.sts.org/sites/default/files/documents/pdf/whattoexpect.pdf)

RECOVERY: After a person has gone under the knife, it is crucial that they understand what they physically can and cannot do. Typically, recovery time is between six to eight weeks depending on the patient. Three things to consistently do after surgery is to keep the incision clean then dry it afterwards with soap and water as well as maintaining a healthy diet. Driving and physical activity are not advised for six to eight weeks after surgery. Though, a patient is advised to slowly increase activity, lift objects less than 10 pounds, take walks daily and refrain from pushing or pulling heavy items. (Source:  http://www.webmd.com/heart-disease/guide/heart-disease-recovering-after-heart-surgery)

NEW TECHNOLOGY: A 3D model heart is the freshest approach to open heart surgery. This is done by a 3D printer that replicates the anatomy of the patient's heart. Made out of plastic, the heart is created in the 3D printer overnight and the next day it is available for doctors to perfect surgical strategies and test new ones before operating on patients. This concept can potentially fit devices such as catheters, valves, and stents to show doctors the exact proportion of the individual's cardiovascular system. (Source: http://abclocal.go.com/kgo/story?section=news/health&id=9145349


Paul J. Wang, MD, Professor of Medicine, Stanford Hospital & Clinics, talks about 3D printing for hearts.

We're talking about moving heart surgery to a whole new level right now. It's going to be more precise and give doctors a better idea. Is this what 3-D printing will do?

Dr. Wang: I'm very excited about what 3D printing can do. It can revolutionize what we do today in terms of medical device innovation and finding new therapies and strategies to treat heart rhythm problems. It enables us to be able to take a concept and translate it into a workable model that we can use for testing. We are trying to design a new tool; we want to really test it on the bench. We really don't have a 3D capability to do that at the present time. This allows us to take a real heart size model with its complexity of structure and to use the design that we've made and then to see whether the physical and mechanical constraints are adequate to operate within that environment. So, that's something that we would have to do experimentally before we get to patients. Then, eventually we can figure out whether that will work in patients.

Was the before model like a hard model or what was it?

Dr. Wang: Prior to having realistic models we couldn't tailor it to the dimensions of the patient, the types of heart disease, etc. We have that potential at the present time. It allows us to be able to have the real dimensions and real detail in terms of structure.

When you talk about experimental devices, what kind are you talking about, catheters or valves?

Dr. Wang: The full range of different therapeutics and diagnostic capabilities are all suitable to using 3D printing and 3D printed models. That could be catheters or it could be artificial valves, valves that you introduce through catheters, or other devices that you might implant in the heart.

Do you see using this before every heart surgery?

Dr. Wang:  There may be a lot of circumstances where we will actually tailor what we do to the actual structure of the heart. We're not there at the present time, but that is a potential for the future. Also, we could design tools that would be able to be used in a specific set of conditions in certain structures.

What are these 3D hearts made out of?

Dr. Wang: They could be made of a variety of circumstances and indeed that's really where some of the biggest innovations are. Currently we use a relatively easy to use hard material, hard plastic material. In the future, they'll be much more textured, they'll have other capabilities. There are structural elements that can be used to grow cells on, things that will get incorporated into and dissolve over time. So, those are things for the future that are being developed now.

When you look at these 3D printers, there's no blood, no heart beating so can it be that close to the real thing?

Dr. Wang: Sure. There are definite limitations. It is not going to show you the ability of the muscle that contract and that kind of thing. At the present time, that's certainly the kinds of models that we use. If you can look at the complexity, the detail of what we have is extraordinary. I've never seen anything like this in some kind of model that we can use. As I mentioned before, what is really important to us in designing new devices is the relative dimensions and positioning of different parts of the heart, whether it be valve leaflets or different muscles. It's very hard to get that from an image that you might see on a screen and when you can actually put a device inside the heart and see how it behaves, that gives you a whole other set of confidence it's likely to work in a human.

Is every heart different?

Dr. Wang: Every heart is clearly different and they have very different dimensions and relationships. When we consider that, we take account of those and make adjustments based on what the characteristics are. That is part of our daily practice, to make those adjustments. We don't have that same ability when we're designing a device. The device generally is going to be fixed in its dimensions. We have to be able to account for a lot of those variations ahead of time and to be able to see what the capabilities are.

Right now you are looking at scans to do all this?

Dr. Wang: Currently we use data predominately from imaging scans that we have. In the future we can do a lot of other things, obviously. We also use the ability of computer assisted drawing programs, which are used for architecture and other engineering design programs that can allow us to position within the heart devices that we've made.

With this 3D printer, you take that information from the same scans. Is that how you get this?

Dr. Wang:  We certainly can start with a scan itself and then generate the heart, but also what we'll do is take mechanical drawings and actually create a model of the device we're creating. Then we can merge the two to see whether they fit, whether the dimensions are correct, and how they'll interact with each other. It is really an important, exciting way in which we're able to advance technology that we couldn't do before.

Could you explain to me how you get to a heart like that?

Dr. Wang: We take the data set from the image and then have to refine it so that you actually only get the area that you're interested in. Essentially the blood pool is invisible in terms of looking at the heart model. We only get the structure of the heart. So, there's a process. It currently is very laborious. It would be hard for us to say with every patient that we see to create a picture of their heart and print because it's so laborious to get it to that state. In the future, that will become streamlined and we'll be able to have that capability.

How long does it take to create a heart like that?

Dr. Wang:  The actual printing is relatively fast. It can be done in a matter of hours. So, we would leave it overnight, we can even get a complex model overnight. The tedious part is actually teasing out the parts of the image as precisely as possible, so that we can get rid of the extraneous information that we don't want printed. That's probably the most tedious part currently.

What's that made of right now?

Dr. Wang: It is a special hard plastic that is one of the most commonly used substances in 3D printing.

Just looking at this, I would think that this would be instrumental in education.  Would it be?

Dr. Wang: Absolutely. I think we have a whole host of different applications in 3D printing that we have not even tried. One of the other aspects is to be able to have them understand how different tools can be constructed. In the past, for example, we might create a diagram and you would say, okay well let's see if that might work. Now, overnight we can get the parts and see whether in fact that will function. You will be able to really test whether your own design concept can really be translated into effective practice.

Have you used this yet in practice?

Dr. Wang: We use it mainly in device innovations. We do this all the time. So, in the past if we wanted to create something on a very small scale to generate a working apparatus, I would go to a machinist and give them the specifications. Then, maybe I'd have it two or three months later. Here we can simply go to the computer on one of these assisted drawing programs and then we can actually create it. It basically pops out and we get to work with it the next day. It allows us to iterate in a very fast way so that over a series of days we can then see whether the concept that we've then adjusted and altered would produce the outcome that we want. It might have taken months or even a year in the past to be able to get to that point. We have a real ability to accelerate the pace of innovation and that's one of the most exciting things about 3D imaging.

As a surgeon, do you have a device that may not work as well as this?

Dr. Wang: Well, certainly we always go through an iteration process any time we develop a new tool and so that's going to involve many, many steps of testing for safety really to make sure it's effective. We want to do the best we can before we get to patients. We want to be able to solve the problems and understand better what the constraints are. The more we have the ability to 3-Dimensonally deal with those mechanical and structural elements and characteristics of the tools we're designing the better, in my opinion. We'll get so much farther along in terms of designing.

So what's next for this?

Dr. Wang: I think we are looking at new materials that we need to use for designing hearts, but also for tools that we make. So we're in the medical innovation device program and we're trying to create new designs and new therapies for people. To have a greater range of tissue, properties, and materials that we use, that's really the next step for us. There are a variety of different ways that people will start to use artificial tissues.

What do you mean by artificial tissues? Would you print this out of artificial tissue then?

Dr. Wang: We are not doing this work currently, but others are and there are several avenues in which they're proceeding. One is that they're actually creating a so called scaffold, much as you would do for a shell of a house. You are able to then have cells grow on that structure to provide a certain structural element for it.

Is that the same as 3D printing then?

Dr. Wang: Well, we would 3D print the scaffold or the structure in which it would sit and the tissues then grow to conform that area.

What's this mean for everyday people?

Dr. Wang: I think 3D printing is going to be a revolution in terms of what we do in medicine, what we do in all parts of our life. So, I think the ability to transform what we think conceptually whether it is on a page or now a screen to be able to see it and hold it and work with it is really just an extension of what we do in real life. The ability to have an object that you can hold and work with is really something that we're very familiar with as humans. In fact, if you could argue while working on a screen it's kind of artificial; this is getting back to what I think people are mainly used to working with. We've just never been able to do it very effectively before. We could only deal with pictures of things, copies of things that are on a screen or in a book. Now, we can actually have a real life model that we can make.


Ashley Georgian
Senior Media Relations Manager
Stanford Hospital & Clinics