Medtronic, Inc. (NYSE: MDT) today announced the results of a
double-blind, randomized study, ISSUE-3, which found that patients who
suffered from fainting due to neurocardiogenic syncope had fewer
fainting occurrences when treated with a Medtronic pacemaker. The
results, which found a statistically and clinically significant 57
percent relative reduction of fainting recurrence in patients at two
years, were presented today in a late-breaking clinical trial session at
the American College of Cardiology's (ACC's) 61st Annual Scientific
Session in Chicago.
In the study, patients at high risk for syncope recurrence (known as
asystolic neurally-mediated syncope or NMS) were identified through the
use of Medtronic's Reveal® family of Insertable Cardiac Monitors (ICM),
thereby allowing physicians to determine which patients could benefit
from a pacemaker implant.
"This study adds to the strength of clinical evidence affirming the
effectiveness of pacemakers in reducing the recurrence of asystolic
syncope, allowing us to determine which patients may benefit best from
pacing," said Michele Brignole, M.D., Ospedali del Tigullio in Lavagna,
Italy and the principal investigator of ISSUE-3 (International Study
on Syncope of Uncertain Etiology 3). "Based on
these compelling results, the ISSUE investigators are hopeful that the
clinical implications of this study will be taken into account when
drafting updates to the current guidelines for these patients."
While a previous observational study, ISSUE-2 (International Study
on Syncope of Uncertain Etiology-2), showed that
the use of an ICM effectively diagnosed asystolic syncope, thereby
leading to effective treatment outcomes, the ISSUE-3 study was needed to
confirm these results through a more rigorous, randomized controlled
The ISSUE-3 study was conducted in 51 centers in Western Europe and
Canada in two phases: a screening phase, followed by a treatment phase.
From September 2006 to November 2011, 511 patients met the inclusion
criteria and received a Reveal device to assist with the diagnosis of
each patient's syncope. Results of the ISSUE-3 include:
Fainting reoccurred in 185 of the 511 study patients (36 percent).
Fainting was documented by the ICM in 141 (76 percent) of these
The Reveal ICM diagnosed about half (51 percent) of patients with
reoccurring fainting as an asystolic event, indicating them for a
pacemaker and making them eligible for the treatment phase of the
study. These patients received a dual-chamber Medtronic pacemaker and
were randomized 1:1 (pacemaker on and pacemaker off).
The treatment phase of the study demonstrated significant reduction in
recurrence of fainting in patients who received Medtronic pacemaker
therapy. For patients receiving pacemaker implants, the fainting
recurrence rate was 25 percent when the pacemaker was turned on and the
fainting recurrence rate was 57 percent when the pacemaker was turned
off (this condition is associated with a drop in blood pressure separate
from the asystole).
"This study shows that a difficult-to-diagnose patient population can be
identified early in the patient care pathway through the use of
insertable cardiac monitors, and that treatment is available and
effective for patients with asystolic syncope," said Elizabeth Hoff,
vice president and general manager of Cardiac Connected Care at