Eden Prairie's Sunshine Heart Inc. has restarted its pivotal clinical trial and is speeding toward an early analysis that could lead to quicker approval for its implantable heart-failure therapy, the C-Pulse system.

Sunshine Heart announced in March that it halted its national, randomized study of up to 388 patients after four of the first 20 people in the clinical trial died. Study rules required a "pause" in such a situation, even if the deaths were not related to the device.

An independent panel in April ruled that the fatalities were not related to the device in the Counter HF clinical trial. This week, the company told investors that the Food and Drug Administration is allowing the study to resume, after seeing the company's proposal to change how patients are selected to take part.

"Resuming enrollment in Counter HF has been our top priority," Sunshine Heart CEO Dave Rosa said in a news release Tuesday. "The proposed protocol modifications have enhanced an already robust protocol, and should increase the likelihood of success."

The C-Pulse Heart Assist System is a partly implantable device designed to treat heart failure by helping the heart beat. It includes a cuff surgically implanted around the heart's main artery that contracts and expands in time with the natural heart beat, timed to reduce the workload on the left ventricle while improving circulation in the arteries that supply blood to the heart muscle.

The company finished its early feasibility study in November 2011, and a year later got FDA approval to start its larger pivotal trial examining the safety and effectiveness of the therapy. The goal is to see whether a group of randomized patients with the device will have fewer hospitalizations or deaths from heart failure than patients in the control group who didn't get the therapy.

Sunshine Heart announced last February that the FDA had approved an interim analysis of the study data collected so far, with the goal of potentially reducing the time to approval for the device if the data support it. "FDA approval to resume study enrollment will now allow the company to progress expeditiously towards that goal," a company statement said.

Joe Carlson • 612-673-4779

Twitter: @_JoeCarlson