Medtronic is expected to publicly detail its failed renal denervation pivotal study on March 29

Medtronic ($MDT) dropped a bomb in January when it revealed that its Symplicity renal denervation device failed to significantly lower blood pressure in patients with drug-resistant hypertension during a pivotal U.S. trial. At long last, the Minnesota med tech giant is expected to reveal details about what went wrong at the American College of Cardiology meeting in Washington, DC, on Saturday, March 29.

Forbes reported recently that Medtronic would outline at the ACC conference what happened during the 535-patient trial to cause Symplicity to fall short, even though many widely expected the device would sail toward U.S. approval. Symplicity has already been available in 80-plus countries outside of the U.S., but the FDA's blessing would be key toward giving Symplicity major market traction.

In a FierceMedicalDevices interview after the disappointing results, Medtronic CEO Omar Ishrak said that the Symplicity HTN-3 trial involved "an exciting approach" to renal denervation and stressed that Medtronic would work hard to understand what happened before evaluating next steps.

Medtronic may also face heat from findings that will be presented at the ACC conference from the Global Symplicity Registry. Forbes noted that the findings will come out a day later, involving data from use of the treatment in over 1,000 patients in Europe (where Symplicity has a CE mark).

Among the companies that will be likely watching closely: Boston Scientific ($BSX). The Massachusetts medical device company has said that it wants to move ahead with its renal denervation program, which uses an approach similar to Medtronic's, but would scrutinize Medtronic's results when they became known.

St. Jude Medical ($STJ), whose renal denervation program is similar to Medtronic's and Boston Scientific's, has said that it would plow ahead with its own program. Johnson & Johnson's ($JNJ) Cordis division has also advanced its Renlane renal denervation system and recently won a CE mark in Europe to use the device to treat drug-resistant hypertension.

- read more in the Forbes piece