User Manual Part 4

D-6
CLINICAL STU DY - CONTAK CD
or CRT On (VDD). The study began as a crossover design (called "Phase I")
and enrolled 248 patients with a primary endpoint of functional status with
three months of follow-up. The study was later modified to a parallel design
(called "Phase II") and enrolled 333 patients with a longer, six-month follow-up.
Thedatafromthefirst three months of the crossover phase were pooled
with data obtained from the six-month parallel phase. The visit schedule
and testing requirements remained the same. Additionally, while the study
originally used the VENTAK CHF ICD in conjunction with epicardial leads
placed via thoracotomy, the CONTAK CD CRT-D and EASY TRAK lead (placed
transvenously) were added to the protocol later in the study.
INCLUSION/EXCLUSION CRITERIA
Patients enrolled in the study were required to meet the following inclusion
criteria:
• Meet the general indication for ICD implant
• Symptomatic heart failure despite optimal drug therapy (ACE inhibitors with
diuretic and/or digoxin, as determ ined to be indicated a nd tolerated by
the patient’s physician-investigator)
• Left ventricula r ejection fraction ≤ 35%
• QRS duration ≥ 120 ms
•Age≥ 18 years
• Normal sinus node function
Patients were excluded from the investigation if they met any of the following
criteria:
• Meet the general indications for permanent antibradycardia pacing,
including pacemaker dependence
• Have chronic, medically refractory atrial tachyarrhythmias
• Require concomitant cardiac surgery
• Are unable to undergo device implant, including general anesthesia if
required
• Are unable to comply with the protocol and follow-up requirements,
including exercise testing
• Have a life expectancy of less than six m onths due to other medical
conditions
• Have amyloid disease (amyloidosis)
• Have hypertrophic obstructive cardiomyopathy
- DRAFT -