St. Jude Medical announced a key regulatory approval on Wednesday for a heart-device feature that may help reinvigorate sales of complex pacemakers and defibrillators systems by letting more patients with heart-failure benefit from the therapy.

The Food and Drug Administration has approved commercial sales of a technology called MultiPoint Pacing (MPP), which allows a heart device to deliver electric pulses to the left side of the heart in multiple locations at the same time. Company-sponsored research has found a 19 percent increase in the number of patients who respond to the therapy, compared to traditional systems.

Ineffective pacing of the left side of the heart is a significant problem in cardiology. Cardiac resynchronization therapy (CRT) devices can cost between $10,000 and $20,000 each, yet as many as a third of the machines don't benefit patients after six months because it's so difficult for doctors to place thin wires called leads around the heart.

More than $3 billion will be spent this year on CRT devices, according to various market estimates. CRT defibrillators, which are more than twice as expensive as CRT pacemakers, outsell the cheaper machines seven-to-one. The market is expected to grow about 3 percent this year.

Five years ago St. Jude received approval for a technology it invented called quadripolar pacing, which allowed a heart device to deliver energy from one of four different electrodes on a single wire to restore a normal heart beat. The innovation let more people benefit from CRT, and competitors Medtronic PLC, Boston Scientific Corp. and Biotronik SE & Co. quickly followed suit with their own quadripolar technologies.

St. Jude Medical hopes that its MultiPoint Pacing technology will become the next standard of care, just as quadripolar technology did.

"I think it's going to follow a very similar trajectory," St. Jude Medical Chief Technology Officer Phil Ebeling said. "Quad was a breakthrough technology that really established St. Jude Medical as a leader in this field, and established CRT as a choice. Now you can imagine the next logical step that MPP provides us, which is to build on that and provide outcomes that are even better than what [patients] are experiencing today."

St. Jude said that the FDA has approved MultiPoint Pacing technology for its Quadra Assura MP CRT implantable defibrillator and the Quadra Allure MP CRT pacemaker, as well as two new leads with four electrodes each. The devices will go on sale before August.

The new feature allows a heart doctor to program the device to deliver electric pulses from multiple electrodes simultaneously or in rapid succession. The idea is to give doctors the ability to stimulate a wider area of heart tissue and get a more robust physical response, while avoiding stimulation of the nearby phrenic nerve, which can trigger uncontrollable twitching and malaise and cause the therapy to fail.

"MultiPoint Pacing allows physicians to program two pacing pulses from a single lead, tailoring electrode choice and timing [near-simultaneous or sequential delivery of the pulses] to meet the specific needs of each patient," a company spokeswoman said in an e-mail.

St. Jude's worldwide heart-rhythm device sales were down 15 percent in the quarter ended Jan. 2, compared to the same quarter last year.

"We've been in these situations before, as have our competitors," St. Jude Chief Financial Officer Don Zurbay said after announcing the figures this month. "If you … remember back the last few years, we had a technology that is now the standard of care called quadripolar, and we were the only ones who had it. And in that particular segment of the CRM [cardiac rhythm management] business, we were taking a whole bunch of share while the competitors suffered. Now, they have quadripolar devices."

Meantime, St. Jude is working toward a quick approval of pacemakers and defibrillators that are compatible with magnetic resonance imaging scanners — a feature Medtronic has, and St. Jude and its competitors do not.

St. Jude executives told investors this month that U.S. approvals of MRI-safe devices and MPP technologies will be among the top drivers of its growth in heart devices this year: "In 2016 our product cycle is a path to return STJ to technology leadership in CRM and provide a foundation for sustained growth," a company PowerPoint presentation from Feb. 5 investors' meeting says.

St. Jude told investors this month that U.S. approval for its MRI-safe pacemaker will come during the first half of this year, and its implantable defibrillator and CRT devices will come in 2017. MPP technology will be added to the MRI CRT defibrillators and pacemakers once the FDA allows that.

St. Jude stock rose more than 2 percent to $53.15 per share Wednesday.

Also Wednesday, St. Jude announced FDA approval for a different device — the Axium Neurostimulator System, which treats chronic pain by electrically stimulating a dense cluster of nerves woven into the spinal cord called the dorsal root ganglion.

The device was approved to treat moderate to severe intractable pain in the lower limbs in adults. Last April St. Jude agreed to pay up to $215 million to acquire the company that made the device.

Joe Carlson • 612-673-4779

Twitter: @_JoeCarlson