User Manual Part 4

D-8
CLINICAL STU DY - CONTAK CD
DEMOGRAPHIC DATA
The CONTAK CD Study included patients with symptomatic heart failure
despite optimal drug therapy as defined in the inclusion criteria. The population
included patients who were NYHA Class II, III, or IV at the time of implant.
Based upon the clinical results from the covariate analyses in this study and the
internal consistency of th ese c linical findings with those from other completed
CRT studies, the patient subgroup with NYHA Class III/IV heart failure in this
study was examined further.
• All Patients ––all patients (NYHA Class II/III/IV at the time of implant)
implanted with an investigational system (N = 501). Ten patients died
and one withdrew before the post-recovery visit. Therefore, therapy
effe ctiveness analyses used N = 490.
• NYHA Class III/IV (Advanced Heart Failure)––this subgroup was defined
as those patients with mo derate to severe heart failure at the time of the
Post-Recovery Visit (N = 227). A percentage of patients either had an
improvement or worsening of their NYHA Class during the post-implant
recovery period. The patients in the Advanced Heart Failure subgroup
were only those who remained in NYHA Class III/IV at the end of the
post-recovery period. This subgroup was determined from interaction
analysis of preselected covariates with the functional status endpoints.
ENDPOINTS
The CONTAK CD Study had three investigational elements consisting of the
following components:
• CRT effectiveness
– Primary––composite endpoint consisting of all-cause m ortality,
hospitalization for heart failure, an d ventricular tachyarrhythmia
requiring device interve ntion
– Secondary–Peak VO
2
derived from a symptom-limited exercise test
and Quality of Life as measured by the Minnesota Living with Heart
Failure Questionnaire
®
– Additional––Six-Minute Walk, NYHA Class, Echocardiographic
Analysis, Change in Norepinephrine, and Change in Heart Rate
- DRAFT -