Cardiac medical device maker AtriCure Inc. (NSDQ:ATRC) closed enrollment early on a hybrid ablation feasibility trial for treatment of atrial fibrillation.

The dual epicardial/endocardial procedure (DEEP) combined ablation from outside and inside the heart as part of a single session, but AtriCure decided that splitting the procedure into two stages may be the more popular approach for most surgeons.

The West Chester, Ohio-based company stopped enrollment after reaching 24 of 30 total patients in hopes of better preparing for a pivotal trial and eventual commercialization, president & CEO David Drachman said in prepared remarks.

"This feasibility study has demonstrated that the single session procedure is highly encouraging," Drachman said. "However, it can present scheduling and logistical challenges as we look to widespread adoption. As a result, we are in the process of reviewing staged procedure alternatives and we plan to discuss these options with the FDA in the near term."

The hybrid procedure, which combines AtriCure’s minimally invasive surgical ablation devices with a catheter-based ablation system from BioSense Webster, holds a U.S. market potential of $2 billion, Drachman has previously said.

But the Cincinnati-area company will likely have to wait awhile before it begins to cash in. Over the summer CFO Julie Piton estimated the company wouldn’t obtain the regulatory approval couldn’t begin marketing its device for the procedure until 2015 — at the earliest.

So far, results from the existing cohort in the DEEP trial look promising, with no episodes of atrial fibrillation or atrial flutter among seven patients for which 6-month follow-up data is available, according to a press release.

Among all 24 enrolled patients there were seven reported adverse events, but only one was attributed to the device. One patient suffered a stroke that lead to death after one month.