Francis J. Podbielski, MD, FCCP, comments on CRT-D
Article Type
Changed
Wed, 01/02/2019 - 09:52

 

– Patients with mild heart failure symptoms, left bundle branch block, and a left ventricular ejection fraction of 31% to 44% who received cardiac resynchronization therapy with a built-in defibrillator experienced a significant reduction in all-cause mortality, compared with those randomized to an implantable cardioverter-defibrillator alone during 7 years of follow-up.

These results from a new MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) long-term follow-up substudy “suggest that patients with a relatively preserved ejection fraction greater than 30% benefit from CRT-D [cardiac resynchronization therapy defibrillator] and could potentially be considered for this therapy,” said Katherine Vermilye, MD, at the annual meeting of the American College of Cardiology.

Dr. Katherine Vermilye
Bruce Jancin/Frontline Medical News
Dr. Katherine Vermilye
This represents a broadening beyond the conclusions earlier reached in the landmark MADIT-CRT trial. In the primary report, MADIT-CRT investigators concluded that CRT-D significantly reduced the risk of heart failure events, compared with an implantable cardioverter defibrillator (ICD) alone during an average follow-up of 2.4 years in patients with mild symptoms of either ischemic or nonischemic cardiomyopathy, a wide QRS duration, an left ventricular ejection fraction (LVEF) of 30% or less, and left bundle branch block, but not in those who didn’t have left bundle branch block (N Engl J Med. 2009 Oct 1;361[14]:1329-38).

In a subsequent publication, the MADIT-CRT investigators reported that, with extension of follow-up to 7 years, CRT-D also provided a significant benefit in terms of all-cause mortality in addition to the reduced rate of heart failure events (N Engl J Med. 2014 May 1;370[18]:1694-701).

However, even though an LVEF of 30% or less was a requirement for participation in MADIT-CRT, it turned out that, when the initial screening echocardiograms were eventually analyzed in a central core laboratory, one-third of study participants actually had a baseline LVEF of 31% to 44%, with the majority of excessive values being in the 31%-35% range.

Dr. Vermilye, of the University of Rochester in New York, presented a post hoc analysis of long-term outcomes in the subgroup having a baseline LVEF greater than 30%. They totaled 450 of 1,224 MADIT-CRT participants with left bundle branch block. They were significantly older and more likely to be female than the 824 subjects with an LVEF of 30% or less. They also had a shorter QRS duration – an average of 160 ms, versus 165 ms in patients with an LVEF of 30% or lower – and a smaller baseline left ventricular end systolic volume of 151 mL, compared with 196 mL in patients with a lower LVEF.

In a multivariate Cox regression analysis adjusted for potential confounders, CRT-D in patients with a baseline LVEF greater than 30% was associated with a 54% reduction in the risk of all-cause mortality at 7 years of follow-up, compared with receipt of an ICD-only device and with a smaller yet significant 31% reduction in risk in those with an LVEF of 30% or less. Worsening heart failure events were reduced by 64% in patients with a baseline LVEF greater than 30% who received CRT-D, compared with ICD-only, and by 54% in those with a lower baseline LVEF.

The reduction in all-cause mortality seen with CRT-D was confined to patients who were high responders to CRT as defined echocardiographically by at least a 35% change in left ventricular end systolic volume 1 year post implantation. They had an 85% reduction in the risk of death during 7 years of follow-up with CRT-D if their baseline LVEF was greater than 30% and a 58% relative risk reduction if their LVEF was 30% or less.

In contrast, CRT-D brought a significantly reduced risk of heart failure events regardless of whether a patient was a low or high responder, although the magnitude of benefit was greater in the high responders. Among patients with a baseline LVEF greater than 30%, CRT-D low responders had a 52% reduction in risk of heart failure events, compared with ICD recipients, while CRT-D high responders had an 81% relative risk reduction. Similarly, in patients with a baseline LVEF of 30% or less, CRT-D low responders had 48% reduction in heart failure events and high responders had a 79% risk reduction, compared with the ICD-only group.

Because this is a post hoc analysis, these new MADIT-CRT findings require validation in future studies, Dr. Vermilye observed.

MADIT-CRT was supported by Boston Scientific. Dr.. Vermilye reported having no financial conflicts.

Body

The authors demonstrate the benefit of cardiac resynchronization therapy in patients with a defibrillator.  The reduction in mortality at 5 years was greater in high responders to CRT-D, although overall mortality was significantly reduced in all comers.

Dr. Francis J. Podbielski

Name
Francis J. Podbielski, MD
Meeting/Event
Publications
Topics
Sections
Meeting/Event
Meeting/Event
Body

The authors demonstrate the benefit of cardiac resynchronization therapy in patients with a defibrillator.  The reduction in mortality at 5 years was greater in high responders to CRT-D, although overall mortality was significantly reduced in all comers.

Dr. Francis J. Podbielski

Body

The authors demonstrate the benefit of cardiac resynchronization therapy in patients with a defibrillator.  The reduction in mortality at 5 years was greater in high responders to CRT-D, although overall mortality was significantly reduced in all comers.

Dr. Francis J. Podbielski

Name
Francis J. Podbielski, MD
Name
Francis J. Podbielski, MD
Title
Francis J. Podbielski, MD, FCCP, comments on CRT-D
Francis J. Podbielski, MD, FCCP, comments on CRT-D

 

– Patients with mild heart failure symptoms, left bundle branch block, and a left ventricular ejection fraction of 31% to 44% who received cardiac resynchronization therapy with a built-in defibrillator experienced a significant reduction in all-cause mortality, compared with those randomized to an implantable cardioverter-defibrillator alone during 7 years of follow-up.

These results from a new MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) long-term follow-up substudy “suggest that patients with a relatively preserved ejection fraction greater than 30% benefit from CRT-D [cardiac resynchronization therapy defibrillator] and could potentially be considered for this therapy,” said Katherine Vermilye, MD, at the annual meeting of the American College of Cardiology.

Dr. Katherine Vermilye
Bruce Jancin/Frontline Medical News
Dr. Katherine Vermilye
This represents a broadening beyond the conclusions earlier reached in the landmark MADIT-CRT trial. In the primary report, MADIT-CRT investigators concluded that CRT-D significantly reduced the risk of heart failure events, compared with an implantable cardioverter defibrillator (ICD) alone during an average follow-up of 2.4 years in patients with mild symptoms of either ischemic or nonischemic cardiomyopathy, a wide QRS duration, an left ventricular ejection fraction (LVEF) of 30% or less, and left bundle branch block, but not in those who didn’t have left bundle branch block (N Engl J Med. 2009 Oct 1;361[14]:1329-38).

In a subsequent publication, the MADIT-CRT investigators reported that, with extension of follow-up to 7 years, CRT-D also provided a significant benefit in terms of all-cause mortality in addition to the reduced rate of heart failure events (N Engl J Med. 2014 May 1;370[18]:1694-701).

However, even though an LVEF of 30% or less was a requirement for participation in MADIT-CRT, it turned out that, when the initial screening echocardiograms were eventually analyzed in a central core laboratory, one-third of study participants actually had a baseline LVEF of 31% to 44%, with the majority of excessive values being in the 31%-35% range.

Dr. Vermilye, of the University of Rochester in New York, presented a post hoc analysis of long-term outcomes in the subgroup having a baseline LVEF greater than 30%. They totaled 450 of 1,224 MADIT-CRT participants with left bundle branch block. They were significantly older and more likely to be female than the 824 subjects with an LVEF of 30% or less. They also had a shorter QRS duration – an average of 160 ms, versus 165 ms in patients with an LVEF of 30% or lower – and a smaller baseline left ventricular end systolic volume of 151 mL, compared with 196 mL in patients with a lower LVEF.

In a multivariate Cox regression analysis adjusted for potential confounders, CRT-D in patients with a baseline LVEF greater than 30% was associated with a 54% reduction in the risk of all-cause mortality at 7 years of follow-up, compared with receipt of an ICD-only device and with a smaller yet significant 31% reduction in risk in those with an LVEF of 30% or less. Worsening heart failure events were reduced by 64% in patients with a baseline LVEF greater than 30% who received CRT-D, compared with ICD-only, and by 54% in those with a lower baseline LVEF.

The reduction in all-cause mortality seen with CRT-D was confined to patients who were high responders to CRT as defined echocardiographically by at least a 35% change in left ventricular end systolic volume 1 year post implantation. They had an 85% reduction in the risk of death during 7 years of follow-up with CRT-D if their baseline LVEF was greater than 30% and a 58% relative risk reduction if their LVEF was 30% or less.

In contrast, CRT-D brought a significantly reduced risk of heart failure events regardless of whether a patient was a low or high responder, although the magnitude of benefit was greater in the high responders. Among patients with a baseline LVEF greater than 30%, CRT-D low responders had a 52% reduction in risk of heart failure events, compared with ICD recipients, while CRT-D high responders had an 81% relative risk reduction. Similarly, in patients with a baseline LVEF of 30% or less, CRT-D low responders had 48% reduction in heart failure events and high responders had a 79% risk reduction, compared with the ICD-only group.

Because this is a post hoc analysis, these new MADIT-CRT findings require validation in future studies, Dr. Vermilye observed.

MADIT-CRT was supported by Boston Scientific. Dr.. Vermilye reported having no financial conflicts.

 

– Patients with mild heart failure symptoms, left bundle branch block, and a left ventricular ejection fraction of 31% to 44% who received cardiac resynchronization therapy with a built-in defibrillator experienced a significant reduction in all-cause mortality, compared with those randomized to an implantable cardioverter-defibrillator alone during 7 years of follow-up.

These results from a new MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) long-term follow-up substudy “suggest that patients with a relatively preserved ejection fraction greater than 30% benefit from CRT-D [cardiac resynchronization therapy defibrillator] and could potentially be considered for this therapy,” said Katherine Vermilye, MD, at the annual meeting of the American College of Cardiology.

Dr. Katherine Vermilye
Bruce Jancin/Frontline Medical News
Dr. Katherine Vermilye
This represents a broadening beyond the conclusions earlier reached in the landmark MADIT-CRT trial. In the primary report, MADIT-CRT investigators concluded that CRT-D significantly reduced the risk of heart failure events, compared with an implantable cardioverter defibrillator (ICD) alone during an average follow-up of 2.4 years in patients with mild symptoms of either ischemic or nonischemic cardiomyopathy, a wide QRS duration, an left ventricular ejection fraction (LVEF) of 30% or less, and left bundle branch block, but not in those who didn’t have left bundle branch block (N Engl J Med. 2009 Oct 1;361[14]:1329-38).

In a subsequent publication, the MADIT-CRT investigators reported that, with extension of follow-up to 7 years, CRT-D also provided a significant benefit in terms of all-cause mortality in addition to the reduced rate of heart failure events (N Engl J Med. 2014 May 1;370[18]:1694-701).

However, even though an LVEF of 30% or less was a requirement for participation in MADIT-CRT, it turned out that, when the initial screening echocardiograms were eventually analyzed in a central core laboratory, one-third of study participants actually had a baseline LVEF of 31% to 44%, with the majority of excessive values being in the 31%-35% range.

Dr. Vermilye, of the University of Rochester in New York, presented a post hoc analysis of long-term outcomes in the subgroup having a baseline LVEF greater than 30%. They totaled 450 of 1,224 MADIT-CRT participants with left bundle branch block. They were significantly older and more likely to be female than the 824 subjects with an LVEF of 30% or less. They also had a shorter QRS duration – an average of 160 ms, versus 165 ms in patients with an LVEF of 30% or lower – and a smaller baseline left ventricular end systolic volume of 151 mL, compared with 196 mL in patients with a lower LVEF.

In a multivariate Cox regression analysis adjusted for potential confounders, CRT-D in patients with a baseline LVEF greater than 30% was associated with a 54% reduction in the risk of all-cause mortality at 7 years of follow-up, compared with receipt of an ICD-only device and with a smaller yet significant 31% reduction in risk in those with an LVEF of 30% or less. Worsening heart failure events were reduced by 64% in patients with a baseline LVEF greater than 30% who received CRT-D, compared with ICD-only, and by 54% in those with a lower baseline LVEF.

The reduction in all-cause mortality seen with CRT-D was confined to patients who were high responders to CRT as defined echocardiographically by at least a 35% change in left ventricular end systolic volume 1 year post implantation. They had an 85% reduction in the risk of death during 7 years of follow-up with CRT-D if their baseline LVEF was greater than 30% and a 58% relative risk reduction if their LVEF was 30% or less.

In contrast, CRT-D brought a significantly reduced risk of heart failure events regardless of whether a patient was a low or high responder, although the magnitude of benefit was greater in the high responders. Among patients with a baseline LVEF greater than 30%, CRT-D low responders had a 52% reduction in risk of heart failure events, compared with ICD recipients, while CRT-D high responders had an 81% relative risk reduction. Similarly, in patients with a baseline LVEF of 30% or less, CRT-D low responders had 48% reduction in heart failure events and high responders had a 79% risk reduction, compared with the ICD-only group.

Because this is a post hoc analysis, these new MADIT-CRT findings require validation in future studies, Dr. Vermilye observed.

MADIT-CRT was supported by Boston Scientific. Dr.. Vermilye reported having no financial conflicts.

Publications
Publications
Topics
Article Type
Sections
Article Source

AT ACC 2017

Disallow All Ads
Content Gating
No Gating (article Unlocked/Free)
Alternative CME
Vitals

 

Key clinical point: Cardiac resynchronization therapy with an implantable CRT-D is more beneficial than a defibrillator alone in patients with an LVEF of 31% to 44%, mild heart failure symptoms, and left bundle branch block.

Major finding: The risk of all-cause mortality was reduced by 54% with CRT-D as compared with an ICD alone in MADIT-CRT participants with a baseline LVEF greater than 30% and by 31% in those with an LVEF of 30% or lower.

Data source: An analysis of 7-year rates of all-cause mortality and worsening heart failure events in 1,224 MADIT-CRT participants with left bundle branch block, 450 of whom had a baseline LVEF greater than 30%.

Disclosures: The MADIT-CRT study was supported by Boston Scientific. The presenter reported having no financial conflicts.