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Biventricular Versus Right Ventricular Pacing in Heart Failure Patients With Atrioventricular Block (BLOCK HF) (BLOCK HF)

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Medtronic Cardiac Rhythm and Heart Failure
ClinicalTrials.gov Identifier:
NCT00267098
First received: December 19, 2005
Last updated: February 20, 2014
Last verified: February 2014
Results First Received: December 18, 2013  
Study Type: Interventional
Study Design: Allocation: Randomized;   Intervention Model: Parallel Assignment;   Masking: Double Blind (Participant, Outcomes Assessor);   Primary Purpose: Treatment
Conditions: Atrioventricular Block
Heart Diseases
Intervention: Device: Cardiac Resynchronization Therapy (CRT)

  Participant Flow
  Hide Participant Flow

Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
No text entered.

Pre-Assignment Details
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
No text entered.

Reporting Groups
  Description
No Implant Attempt Subjects who did not undergo an implant attempt of a CRT-P or CRT-D device and were not randomized
Unsuccessful Implants Subjects who underwent an implant attempt of a CRT-P or CRT-D device but were not successfully implanted
CRT-P: Biventricular Pacing Arm Subjects who were implanted with a CRT-P device and randomized to receive biventricular pacing
CRT-P: Right Ventricular Pacing Arm Subjects who were implanted with a CRT-P device and randomized to receive right ventricular pacing
CRT-P: Not Randomized Subjects successfully implanted with a CRT-P device who were not randomized
CRT-D: Biventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive biventricular pacing
CRT-D: Right Ventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive right ventricular pacing.
CRT-D: Not Randomized Subjects successfully implanted with a CRT-D device who were not randomized

Participant Flow:   Overall Study
    No Implant Attempt   Unsuccessful Implants   CRT-P: Biventricular Pacing Arm   CRT-P: Right Ventricular Pacing Arm   CRT-P: Not Randomized   CRT-D: Biventricular Pacing Arm   CRT-D: Right Ventricular Pacing Arm   CRT-D: Not Randomized
STARTED   109   51   243   241   47   106   101   20 
COMPLETED   0   0   149   135   10   66   55   5 
NOT COMPLETED   109   51   94   106   37   40   46   15 
Death                0                0                57                66                14                23                28                9 
Lost to Follow-up                0                0                6                5                2                3                1                1 
Withdrawal by Subject                8                0                24                21                12                9                12                5 
Physician Decision                5                0                7                11                5                4                3                0 
Inclusion/Exclusion Criteria Not Met                96                0                0                0                2                0                0                0 
Unsuccessful Implant Exit Per Protocol                0                51                0                0                0                0                0                0 
Site closure                0                0                0                1                0                1                1                0 
Explanted Medtronic device                0                0                0                1                0                0                0                0 
Non-Medtronic LV Lead Implanted                0                0                0                0                2                0                0                0 
Subject listed for heart transplant                0                0                0                0                0                0                1                0 
Sponsor withdrew subject                0                0                0                1                0                0                0                0 



  Baseline Characteristics
  Hide Baseline Characteristics

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
No text entered.

Reporting Groups
  Description
No Implant Attempt Subjects who did not undergo an implant attempt of a CRT-P or CRT-D device and were not randomized
Unsuccessful Implants Subjects who underwent an implant attempt of a CRT-P or CRT-D device but were not successfully implanted
CRT-P: Biventricular Pacing Arm Subjects who were implanted with a CRT-P device and randomized to receive biventricular pacing
CRT-P: Right Ventricular Pacing Arm Subjects who were implanted with a CRT-P device and randomized to receive right ventricular pacing
CRT-P: Not Randomized Subjects successfully implanted with a CRT-P device who were not randomized
CRT-D: Biventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive biventricular pacing
CRT-D: Right Ventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive right ventricular pacing.
CRT-D: Not Randomized Subjects successfully implanted with a CRT-D device who were not randomized
Total Total of all reporting groups

Baseline Measures
   No Implant Attempt   Unsuccessful Implants   CRT-P: Biventricular Pacing Arm   CRT-P: Right Ventricular Pacing Arm   CRT-P: Not Randomized   CRT-D: Biventricular Pacing Arm   CRT-D: Right Ventricular Pacing Arm   CRT-D: Not Randomized   Total 
Overall Participants Analyzed 
[Units: Participants]
 109   51   243   241   47   106   101   20   918 
Age 
[Units: Years]
Mean (Standard Deviation)
 70.2  (12.6)   71.1  (11.2)   74.4  (10.2)   73.8  (10.8)   79.3  (7.6)   72.0  (9.3)   71.0  (10.0)   74.0  (9.1)   73.2  (10.6) 
Gender 
[Units: Participants]
                 
Female   29   14   62   73   18   19   20   4   239 
Male   80   37   181   168   29   87   81   16   679 
Race/Ethnicity, Customized 
[Units: Participants]
                 
Subject did not offer ethnicity   6   2   6   5   1   4   3   0   27 
African American   10   3   8   10   0   4   4   1   40 
Asian   0   0   0   0   1   0   0   0   1 
Caucasian   91   45   225   224   43   96   90   18   832 
Hispanic   1   0   3   1   2   2   2   1   12 
Native American   0   0   0   1   0   0   0   0   1 
Other   1   1   1   0   0   0   2   0   5 
Region of Enrollment 
[Units: Participants]
                 
United States   109   46   232   231   47   104   98   19   886 
Canada   0   5   11   10   0   2   3   1   32 


  Outcome Measures
  Show All Outcome Measures

1.  Primary:   Mortality, Heart Failure-related Urgent Care Visits, or Significant Increase in Left Ventricular End Systolic Volume Index (LVESVI)   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

2.  Secondary:   All-Cause Mortality   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

3.  Secondary:   All-Cause Mortality or Heart Failure-related Hospitalization   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

4.  Secondary:   All-Cause Mortality or Significant Increase in Left Ventricular End Systolic Volume Index   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

5.  Secondary:   First Heart Failure Hospitalization   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

6.  Secondary:   Days Hospitalized for Heart Failure   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

7.  Secondary:   Change in New York Heart Association Classification   [ Time Frame: Randomization to 24 Months ]

8.  Secondary:   Change in Heart Failure Stage   [ Time Frame: Randomization to 24 Months ]

9.  Secondary:   Change in Cardiovascular Medications   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]
  Hide Outcome Measure 9

Measure Type Secondary
Measure Title Change in Cardiovascular Medications
Measure Description The endpoints are what classes of drugs (e.g. Beta blockers, Diuretics, Nitrates, etc.) each subject was on at the time of scheduled visits (e.g Randomization, 6 months, 12 months, etc.)
Time Frame Participants were followed for the duration of the study, an average of 39.8 months post-randomization.  

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
Because indications for defibrillation devices like CRT-Ds are defined by characteristics that relate to medication guidelines, medication results are presented separately for each device group. Medications were assessed only for subjects who completed visits (denoted as "Subjects with Medications Assessed").

Reporting Groups
  Description
CRT-P: Biventricular Pacing Arm Subjects implanted with a CRT-P device and randomized to receive biventricular pacing
CRT-P: Right Ventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive right ventricular pacing.
CRT-D: Biventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive biventricular pacing
CRT-D: Right Ventricular Pacing Arm Subjects implanted with a CRT-D device and randomized to receive right ventricular pacing

Measured Values
   CRT-P: Biventricular Pacing Arm   CRT-P: Right Ventricular Pacing Arm   CRT-D: Biventricular Pacing Arm   CRT-D: Right Ventricular Pacing Arm 
Participants Analyzed 
[Units: Participants]
 243   241   106   101 
Change in Cardiovascular Medications 
[Units: Participants]
       
Randomization: Subjects on ACE-Inhibitors/ARBs   173   179   93   84 
Randomization: Subjects on Beta Blockers   186   191   98   93 
Randomization: Subjects on Vasodilators/Nitrates   53   44   31   20 
Randomization: Subjects on Aldosterone Antagonists   33   25   19   25 
Randomization: Subjects on Diuretics   156   158   74   74 
6 Months: Subjects with Medications Assessed   226   207   94   89 
6 Months: Subjects on ACE-Inhibitors/ARBs   162   152   77   73 
6 Months: Subjects on Beta Blockers   175   171   87   79 
6 Months: Subjects on Vasodilators/Nitrates   46   42   24   12 
6 Months: Subjects on Aldosterone Antagonists   31   21   20   25 
6 Months: Subjects on Diuretics   148   137   66   70 
12 Months: Subjects with Medications Assessed   205   200   83   81 
12 Months: Subjects on ACE-Inhibitors/ARBs   147   151   72   70 
12 Months: Subjects on Beta Blockers   158   170   79   75 
12 Months: Subjects on Vasodilators/Nitrates   45   43   22   13 
12 Months: Subjects on Aldosterone Antagonists   23   20   13   21 
12 Months: Subjects on Diuretics   133   131   57   60 
18 Months: Subjects with Medications Assessed   169   181   78   72 
18 Months: Subjects on ACE-Inhibitors/ARBs   121   137   62   58 
18 Months: Subjects on Beta Blockers   134   152   75   63 
18 Months: Subjects on Vasodilators/Nitrates   36   44   22   11 
18 Months: Subjects on Aldosterone Antagonists   16   21   9   20 
18 Months: Subjects on Diuretics   111   125   51   59 
24 Months: Subjects with Medications Assessed   152   157   69   67 
24 Months: Subjects on ACE-Inhibitors/ARBs   114   119   58   56 
24 Months: Subjects on Beta Blockers   118   133   65   63 
24 Months: Subjects on Vasodilators/Nitrates   28   37   23   10 
24 Months: Subjects on Aldosterone Antagonists   18   15   13   18 
24 Months: Subjects on Diuretics   97   104   47   56 
30 Months: Subjects with Medications Assessed   130   131   53   57 
30 Months: Subjects on ACE-Inhibitors/ARBs   92   102   42   47 
30 Months: Subjects on Beta Blockers   104   114   51   56 
30 Months: Subjects on Vasodilators/Nitrates   23   28   16   11 
30 Months: Subjects on Aldosterone Antagonists   14   14   10   15 
30 Months: Subjects on Diuretics   82   90   36   50 
36 Months: Subjects with Medications Assessed   109   112   42   44 
36 Months: Subjects on ACE-Inhibitors/ARBs   76   85   30   37 
36 Months: Subjects on Beta Blockers   86   97   41   44 
36 Months: Subjects on Vasodilators/Nitrates   21   24   14   9 
36 Months: Subjects on Aldosterone Antagonists   10   19   8   10 
36 Months: Subjects on Diuretics   69   79   34   37 
42 Months: Subjects with Medications Assessed   94   99   38   42 
42 Months: Subjects on ACE-Inhibitors/ARBs   69   73   27   35 
42 Months: Subjects on Beta Blockers   75   86   35   42 
42 Months: Subjects on Vasodilators/Nitrates   15   22   12   10 
42 Months: Subjects on Aldosterone Antagonists   8   13   9   12 
42 Months: Subjects on Diuretics   57   71   31   39 

No statistical analysis provided for Change in Cardiovascular Medications



10.  Secondary:   Frequency of Adverse Events Post-randomization   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

11.  Secondary:   Cardiovascular-related Healthcare Utilizations   [ Time Frame: Participants were followed for the duration of the study, an average of 39.8 months post-randomization. ]

12.  Secondary:   Change in Quality of Life at 6 Months   [ Time Frame: Randomization to 6 Months ]

13.  Secondary:   Change in Quality of Life at 12 Months   [ Time Frame: Randomization to 12 months ]

14.  Secondary:   Change in Quality of Life at 18 Months   [ Time Frame: Randomization to 18 Months ]

15.  Secondary:   Change in Quality of Life at 24 Months   [ Time Frame: Randomization to 24 Months ]

16.  Secondary:   Change in Left Ventricular Ejection Fraction (LVEF) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

17.  Secondary:   Change in Left Ventricular Ejection Fraction (LVEF) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

18.  Secondary:   Change in Left Ventricular Ejection Fraction (LVEF) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

19.  Secondary:   Change in Left Ventricular Ejection Fraction (LVEF) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

20.  Secondary:   Change in Left Ventricular End Systolic Volume Index (LVESVI) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

21.  Secondary:   Change in Left Ventricular End Systolic Volume Index (LVESVI) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

22.  Secondary:   Change in Left Ventricular End Systolic Volume Index (LVESVI) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

23.  Secondary:   Change in Left Ventricular End Systolic Volume Index (LVESVI) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

24.  Secondary:   Change in Left Ventricular End Diastolic Volume Index (LVEDVI) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

25.  Secondary:   Change in Left Ventricular End Diastolic Volume Index (LVEDVI) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

26.  Secondary:   Change in Left Ventricular End Diastolic Volume Index (LVEDVI) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

27.  Secondary:   Change in Left Ventricular End Diastolic Volume Index (LVEDVI) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

28.  Secondary:   Change in Left Ventricular Mass (LV Mass) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

29.  Secondary:   Change in Left Ventricular Mass (LV Mass) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

30.  Secondary:   Change in Left Ventricular Mass (LV Mass) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

31.  Secondary:   Change in Left Ventricular Mass (LV Mass) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

32.  Secondary:   Change in Left Ventricular End Diastolic Dimension (LVEDD) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

33.  Secondary:   Change in Left Ventricular End Diastolic Dimension (LVEDD) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

34.  Secondary:   Change in Left Ventricular End Diastolic Dimension (LVEDD) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

35.  Secondary:   Change in Left Ventricular End Diastolic Dimension (LVEDD) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

36.  Secondary:   Change in Left Ventricular End Systolic Dimension (LVESD) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

37.  Secondary:   Change in Left Ventricular End Systolic Dimension (LVESD) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

38.  Secondary:   Change in Left Ventricular End Systolic Dimension (LVESD) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

39.  Secondary:   Change in Left Ventricular End Systolic Dimension (LVESD) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

40.  Secondary:   Change in Mitral Regurgitation From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

41.  Secondary:   Change in Mitral Regurgitation From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

42.  Secondary:   Change in Mitral Regurgitation From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

43.  Secondary:   Change in Mitral Regurgitation From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

44.  Secondary:   Change in Cardiac Index From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

45.  Secondary:   Change in Cardiac Index From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

46.  Secondary:   Change in Cardiac Index From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

47.  Secondary:   Change in Cardiac Index From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

48.  Secondary:   Change in Interventricular Mechanical Delay (IVMD) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

49.  Secondary:   Change in Interventricular Mechanical Delay (IVMD) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

50.  Secondary:   Change in Interventricular Mechanical Delay (IVMD) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

51.  Secondary:   Change in Interventricular Mechanical Delay (IVMD) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

52.  Secondary:   Change in E Wave/A Wave Ratio (E:A Ratio) From Randomization to 6 Months   [ Time Frame: Randomization to 6 Months ]

53.  Secondary:   Change in E Wave/A Wave Ratio (E:A Ratio) From Randomization to 12 Months   [ Time Frame: Randomization to 12 Months ]

54.  Secondary:   Change in E Wave/A Wave Ratio (E:A Ratio) From Randomization to 18 Months   [ Time Frame: Randomization to 18 Months ]

55.  Secondary:   Change in E Wave/A Wave Ratio (E:A Ratio) From Randomization to 24 Months   [ Time Frame: Randomization to 24 Months ]

56.  Secondary:   Clinical Composite Score at 6 Months   [ Time Frame: Randomization to 6 Months ]

57.  Secondary:   Clinical Composite Score at 12 Months   [ Time Frame: Randomization to 12 Months ]

58.  Secondary:   Clinical Composite Score at 18 Months   [ Time Frame: Randomization to 18 Months ]

59.  Secondary:   Clinical Composite Score at 24 Months   [ Time Frame: Randomization to 24 Months ]

60.  Secondary:   CRT-P and CRT-D System Implant Success   [ Time Frame: Initial Implant Procedure ]

61.  Secondary:   Incidence of Ventricular Tachyarrhythmias   [ Time Frame: Participants were followed for the duration of the study, an average of 37.9 months post-randomization among CRT-D subjects. ]


  Serious Adverse Events


  Other Adverse Events


  Limitations and Caveats
  Hide Limitations and Caveats

Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
No text entered.


  More Information
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Certain Agreements:  
Principal Investigators are NOT employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.


Results Point of Contact:  
Name/Title: BLOCK HF Clinical Trial Leader
Organization: Medtronic CRDM Clinical
phone: 763-526-2729
e-mail: medtroniccrmtrials@medtronic.com


Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

Responsible Party: Medtronic Cardiac Rhythm and Heart Failure
ClinicalTrials.gov Identifier: NCT00267098     History of Changes
Other Study ID Numbers: 215
Study First Received: December 19, 2005
Results First Received: December 18, 2013
Last Updated: February 20, 2014