When the heart is too weak to pump blood through the body, a mechanical pump – or, a ventricular assist device (VAD) – is often implanted to help adult patients survive until a heart transplant can be performed. But what about the smallest heart failure patients? Some companies are working to develop pediatric VADs for children, and in some cases, even babies and toddlers.
One such company, Berlin Heart (Berlin), reported late last week that its Excor Pediatric ventricular assist device has received regulatory approval in Canada. The license, with conditions from Health Canada, represents the company's first marketing approval in North America.
The Berlin Heart Excor Pediatric is a mechanical cardiac support system for critically ill pediatric patients suffering from severe heart failure. The device has been used as a short-term, mid-term, and long-term support system, supporting failing hearts from days up to several months.
"What makes the device special is that the actual blood pump comes in six different sizes, so patients of all body sizes can be supported," Linda Buerk, manager of marketing and public relations for Berlin Heart, told Medical Device Daily in an email. "The approval represents such a milestone because physicians and patients now have easier access to the device. Many patients are supported under emergency conditions, meaning time can be a critical factor for successful treatment."
Buerk said the Excor Pediatric device has CE mark approval and is widely used in Europe. The device is under clinical investigation for pediatric patients in the U.S., the company noted.
In a follow-up phone interview, Buerk told MDD that the Excor Pediatric has been used in more than 500 pediatric patients worldwide. The pediatric population is a much smaller patient population for VAD devices than the adult patient population. "For these patients there currently is not any other widely used option for short-, medium-, and long-term support," she added.
The system is designed to bridge patients awaiting heart transplantation until a donor heart becomes available, but has also been used successfully used as a bridge to recovery when a patient's heart was able to recover and work on its own again. Unlike other VADs, Excor Pediatric can be used to support children of all age groups, from newborns up to teenagers, Berlin Heart said.
"The license with conditions represents a milestone reached for children and teenagers suffering from severe heart failure, as the system is now more readily available in Canada," said Johannes Muller, MD, general manager of Berlin Heart. "Since patients often require acute emergency support, this is a major step toward improved care for these potentially terminally ill children."
Since the application for Canadian regulatory approval in September 2007, 21 patients were supported in Canada with Excor Pediatric under special access approval, the company noted.
Excor Pediatric is a pulsatile, pneumatically driven ventricular assist device and can be used to support one or both ventricles, according to Berlin Heart. Since the first application of the ventricular assist device in Canada in July 2002, 39 children and teenagers have been supported with Excor Pediatric, according to the company.
Berlin Heart says it is the "only company worldwide" that develops implantable and external VADs for patients of every age and body size.
But Berlin Heart is not the only company targeting potential VAD use in children. In 2007 World Heart (Oakland, California) reported the success of an animal implant of a miniaturized VAD for pediatric patients (Medical Device Daily, July 17, 2007).
The PediaFlow VAD is being developed to provide medium-term implantable circulatory support to patients from birth to 2 years of age with congenital or acquired heart disease. The company said at the time that the PediaFlow design also is the platform for a future minimally invasive adult VAD, intended to meet a clinical need for earlier-stage heart failure patients.
The PediaFlow is an implantable, magnetically levitated blood pump based on WoldHeart's rotary VAD MagLev technology used in its Levacor device. In its pediatric configuration, the device is designed to provide a flow rate from 0.3 to 1.5 liters per minute.
According to World Heart, the Levacor uses magnetic levitation to fully suspend the spinning rotor, its only moving part, inside a compact housing.
And in 2005 The Cleveland Clinic said it was developing the PediPump, a rotary VAD about the size of a golf tee that the clinic said had the potential to save the lives of even the smallest end-stage heart failure patients (MDD, Aug. 3, 2005).
Similar to the PediaFlow, the PediPump is based on a magnetic bearing-supported, rotary dynamic pump developed especially for children, including newborns. Measuring just 7 mm in diameter by 70 mm in length, the cylindrical-shaped device is much smaller than traditional VADs, the clinic noted. The enabling technology of the PediPump is borrowed from an adult catheter pump in development by The Cleveland Clinic's department of biomedical engineering and Foster-Miller Technologies (Albany, New York).
Brian Duncan, MD, associate staff member of the pediatric and congenital heart surgery division at The Children's Hospital, told MDD at the time that existing support devices for pediatric heart failure patients came with limitations.
For example, the DeBakey VAD Child from MicroMed Technology (Houston) was available at that time through a humanitarian device exemption in the U.S. and was CE mark-approved in Europe, but the patient had to be at least five years old. That device, now known as the HeartAssist5 Pediatric VAD, is now FDA approved as a bridge-to-transplant for pediatric patients age 5 to 16 who are on the waiting list for a transplant. The company introduced the device to the U.S. market in September 2008. It has a direct-flow measurement system intended to provide blood flow data 24/7.