- Email: [email protected]
The use of aortic counterpulsation in United States: What can we learn from administrative databases?
The use of aortic counterpulsation in united states: What can we learn from administrative databases? Ryan McDonough DO, FACC, E. Magnus Ohman MD, FACC PII: DOI: Reference:
S0002-8703(14)00338-X doi: 10.1016/j.ahj.2014.05.013 YMHJ 4635
To appear in:
American Heart Journal
Received date: Accepted date:
20 May 2014 24 May 2014
Please cite this article as: McDonough Ryan, Ohman E. Magnus, The use of aortic counterpulsation in united states: What can we learn from administrative databases?, American Heart Journal (2014), doi: 10.1016/j.ahj.2014.05.013
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
RI P
T
The Use of Aortic Counterpulsation in United States: What Can We Learn from Administrative Databases?
SC
Ryan McDonough DO, FACC and E. Magnus Ohman MD, FACC
MA
NU
From: Division of Cardiovascular Medicine, Department of Medicine, and Program for Advanced Coronary Disease, Duke Clinical Research Institute, Duke University, Durham, North Carolina, 27710, USA
E. Magnus Ohman, MD, FACC
Durham, NC 27710
AC
Tel: 919-681-2069
CE
8676A HAFS Building
PT
Duke University Medical Center
ED
Corresponding author:
Fax: 919-681-6443
E-mail: [email protected]
1
ACCEPTED MANUSCRIPT In the ideal clinical setting, every physician and healthcare system should aggregate their data to be able to better understand how the practice of medicine affects outcomes among their patients. Unfortunately,
T
we are currently far from this state of affairs. Very few healthcare systems collect careful clinical
RI P
information to be able to examine their practice with attention to what drives physician practice and how this affects outcomes. Fortunately, we do not rely on observational data to make an assessment of the risk
SC
and benefit with any procedure, as the majority of cardiovascular devices have gone through an approval process that for higher risk procedures involves a single or multiple randomized trials. However, one
NU
cannot randomize patients in every clinical scenario and there are devices that have been used for many
MA
years that have never been subjected to adequate randomized clinical trials. Aortic counterpulsation (IABP) is one such device that has been in use for nearly 50 years, with limited randomized clinical trials data, but with a large clinical experience.1,2 The initial use was targeted for patients with cardiogenic
ED
shock, but small randomized trials failed to show any reduction in mortality. 3 Recently an adequately
PT
sized clinical trial in cardiogenic shock was completed which also failed to show a reduction in
CE
mortality,4 which has raised the concern that IABP therapy in cardiogenic shock is of little value.
AC
In this issue of the Journal, Patel and colleagues report on a large experience of IABP in the US between 1998 and 2008. 5 Because of the limitations in this administrative database the authors could only examine the use of IABP among patients who also had PCI. Thus this observational analysis does not account for all patients who had IABP in the US during this period. Nevertheless they identified 8,290 incidences where IABP was used in approximately 1.5 million admissions for PCI during this 10-year period. It is not known whether the IABP was used as a treatment for high-risk AMI and cardiogenic shock or for a complication during PCI, which could have been performed for more elective settings. Cardiogenic shock was coded to have occurred in 13,935 (0.9%) of these admissions. This rate is substantially lower than the rate that is generally observed in the community at 2-5% of patients with AMI, 6 suggesting that the vast majority of the patients in this database were patients who had PCI for 2
ACCEPTED MANUSCRIPT non-cardiogenic shock indication where IABP use has been limited and in general not found to be of value unless it was for stabilizing the patient after a complication of PCI such as hemodynamic collapse.
T
It is therefore hard to ascribe what the association of lower IABP use and high mortality means from this
RI P
study. On the one hand it can suggest that non-cardiogenic shock PCI procedures have improved with less acute complications which have been seen in some settings. 7 On the other hand it could also mean
SC
that the incidence of cardiogenic shock is falling because of better and timelier primary PCI in AMI. 8 This is also possible as the majority of patients who develop cardiogenic shock do so later during the
NU
hospitalization after admission. 8 This is partially refuted by the small increase in patients with
MA
cardiogenic shock that had PCI from 0.88% to 1.19% observed in this study. This change of 0.31% suggests that there may have been a 35% increase in the incidence in cardiogenic shock over a 10-year period, which would seem rather large for a short period. Community-based studies from Massachusetts
ED
have shown that the prevalence of cardiogenic shock has remained relatively stable for the last several
PT
decades [6]. Thus it is uncertain if we can conclude much from this study about cardiogenic shock and
CE
PCI.
AC
There is also a possibility that hospitals have coded more patients as having cardiogenic shock over time. If this was done, it would lead to a lower observed mortality among patients with cardiogenic shock that also had PCI. This was indeed found where the mortality dropped from 22.8% to 17.8%. This would represent a 22% relative reduction in mortality during the 10-year period. As all these patients were treated with PCI that has been shown to lower mortality in cardiogenic shock, other factors must be at play. It would seem unlikely that we could attribute this finding to IABP use, as the IABP-SHOCK randomized trial showed no reduction in mortality either at 30-days or at 1 year with this therapy. 9 The ACTION registry is registering all AMI patients at 392 hospitals and has found a 4.3% to 12.5% rate of cardiogenic shock in STEMI and non-STEMI. 10 This would be the best source for detecting changes in the prevalence of AMI and cardiogenic shock over time. Unfortunately, that registry and the current NIS 3
ACCEPTED MANUSCRIPT administrative database only collect outcomes among patients while in the hospital. Both data sets would
RI P
T
benefit from connecting to long-term mortality data.
Interestingly, there is also evidence of changes in the prevalence of AMI among patients having PCI
SC
observed in this study. The rate of PCI in AMI rose by 18% from 2006 to 2008, for which no explanation
MA
fidelity to assess the prevalence of disease states.
NU
is provided. These findings in aggregate suggest that administrative databases may not have the optimal
What guidance can we then take from this study? There is still a great deal of uncertainty on how to best
ED
support patients with AMI complicated by cardiogenic shock. As this is one of the main causes of
PT
mortality in AMI, we must find better ways to manage these patients. The randomized SHOCK trial showed that revascularization lowered 1-year mortality. However, since that landmark study, we have
CE
not found other better treatment strategies. The use of IABP has undisputed hemodynamic benefit, while modest, in patients with cardiogenic shock. It may therefore still be reasonable to use IABP in this
AC
setting, even if it does not ultimately lower mortality. It is also recommended by the American Heart Association and American College of Cardiology practice guidelines as hemodynamic support in cardiogenic shock and heart failure. Recent devices such as hemo-pump and Impella have been applied in cardiogenic shock, but we lack adequately sized randomized trials to assess their benefit-to-risk ratio. Uniformly, these devices provide better hemodynamic support compared with IABP, but vascular and hemorrhagic complications tend to be higher. 11 Unfortunately, registries can help us better understand the devices in the clinical setting, but they are no substitute for adequately sized randomized clinical trials in cardiogenic shock, which can define the potential best support device to use. Only then can we hope to reduce mortality in cardiogenic shock with certainty.
4
ACCEPTED MANUSCRIPT References:
T
1. Chen EW, Canto JG, Parsons LS, et al, for the NRMI 2 Investigators. Relation Between Hospital
RI P
Intra-Aortic Balloon Counterpulsation Volume and Mortality in Acute Myocardial Infarction
SC
Complicated by Cardiogenic Shock. Circulation. 2003;108:951-7.
2. Curtis JP, Rathore SS, Wang Y, et al. Use and effectiveness of intra-aortic balloon pumps among
NU
patients undergoing high risk percutaneous coronary intervention: insights from the NCDR. Circ
MA
Cardiovasc Qual Outcomes. 2012;5:21-30.
3. Unverzagt S, Machemer MT, Solms A, et al. Intra-aortic balloon pump counterpulsation (IABP) for
PT
ED
myocardial infarction complicated by cardiogenic shock. Cochrane Database Syst Rev. 011;7:CD007398.
4. Thiele H, Zeymer U, Neumann FJ, et al, for the IABP-SHOCK II Trial Investigators. Intra-aortic
CE
balloon support for myocardial infarction with cardiogenic shock. N Engl J Med. 2012;367:1287-96.
AC
5. Patel et al. Am Heart J. 2014.
6. Goldberg RJ, Spencer FA, Gore JM, et al. Thirty-year trends (1975 to 2005) in the magnitude of, management of, and hospital death rates associated with cardiogenic shock in patients with acute myocardial infarction: a population-based perspective. Circulation 2009;119:1211-9.
7. Singh M, Rihal CS, Gersh BJ, et al. Twenty-five year trends in in-hospital and long-term outcome after percutaneous coronary intervention: a single-institution experience. Circulation. 2007;115:28352841.
5
ACCEPTED MANUSCRIPT 8. Jeger RV, Radovanovic D, Hunziker PR, et al, for the AMIS Plus Registry Investigators. Ten-year
T
trends in the incidence and treatment of cardiogenic shock. Ann Intern Med. 2008;149:618-626.
RI P
9. Thiele H, Zeymer U, Neumann FJ, et al, for the Intra-aortic Balloon Pump in cardiogenic shock II (IABP-SHOCK II) trial investigators. Intra-aortic balloon counterpulsation in acute myocardial infarction
SC
complicated by cardiogenic shock (IABP-SHOCK II): final 12 month results of a randomised, open-label
NU
trial. Lancet. 2013;382:1638-45.
MA
10. Anderson ML, Peterson ED, Peng SA, et al. Differences in the profile, treatment, and prognosis of patients with cardiogenic shock by myocardial infarction classification: A report from NCDR. Circ
ED
Cardiovasc Qual Outcomes. 2013 Nov;6(6):708-15.
PT
11. Cheng JM, den Uil CA, Hoeks SE, et al. Percutaneous left ventricular assist devices vs. intra-aortic balloon pump counterpulsation for treatment of cardiogenic shock: a meta-analysis of controlled trials.
AC
CE
Eur Heart J. 2009;30: 2102-2108.
6
S0002-8703(14)00338-X doi: 10.1016/j.ahj.2014.05.013 YMHJ 4635
To appear in:
American Heart Journal
Received date: Accepted date:
20 May 2014 24 May 2014
Please cite this article as: McDonough Ryan, Ohman E. Magnus, The use of aortic counterpulsation in united states: What can we learn from administrative databases?, American Heart Journal (2014), doi: 10.1016/j.ahj.2014.05.013
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
RI P
T
The Use of Aortic Counterpulsation in United States: What Can We Learn from Administrative Databases?
SC
Ryan McDonough DO, FACC and E. Magnus Ohman MD, FACC
MA
NU
From: Division of Cardiovascular Medicine, Department of Medicine, and Program for Advanced Coronary Disease, Duke Clinical Research Institute, Duke University, Durham, North Carolina, 27710, USA
E. Magnus Ohman, MD, FACC
Durham, NC 27710
AC
Tel: 919-681-2069
CE
8676A HAFS Building
PT
Duke University Medical Center
ED
Corresponding author:
Fax: 919-681-6443
E-mail: [email protected]
1
ACCEPTED MANUSCRIPT In the ideal clinical setting, every physician and healthcare system should aggregate their data to be able to better understand how the practice of medicine affects outcomes among their patients. Unfortunately,
T
we are currently far from this state of affairs. Very few healthcare systems collect careful clinical
RI P
information to be able to examine their practice with attention to what drives physician practice and how this affects outcomes. Fortunately, we do not rely on observational data to make an assessment of the risk
SC
and benefit with any procedure, as the majority of cardiovascular devices have gone through an approval process that for higher risk procedures involves a single or multiple randomized trials. However, one
NU
cannot randomize patients in every clinical scenario and there are devices that have been used for many
MA
years that have never been subjected to adequate randomized clinical trials. Aortic counterpulsation (IABP) is one such device that has been in use for nearly 50 years, with limited randomized clinical trials data, but with a large clinical experience.1,2 The initial use was targeted for patients with cardiogenic
ED
shock, but small randomized trials failed to show any reduction in mortality. 3 Recently an adequately
PT
sized clinical trial in cardiogenic shock was completed which also failed to show a reduction in
CE
mortality,4 which has raised the concern that IABP therapy in cardiogenic shock is of little value.
AC
In this issue of the Journal, Patel and colleagues report on a large experience of IABP in the US between 1998 and 2008. 5 Because of the limitations in this administrative database the authors could only examine the use of IABP among patients who also had PCI. Thus this observational analysis does not account for all patients who had IABP in the US during this period. Nevertheless they identified 8,290 incidences where IABP was used in approximately 1.5 million admissions for PCI during this 10-year period. It is not known whether the IABP was used as a treatment for high-risk AMI and cardiogenic shock or for a complication during PCI, which could have been performed for more elective settings. Cardiogenic shock was coded to have occurred in 13,935 (0.9%) of these admissions. This rate is substantially lower than the rate that is generally observed in the community at 2-5% of patients with AMI, 6 suggesting that the vast majority of the patients in this database were patients who had PCI for 2
ACCEPTED MANUSCRIPT non-cardiogenic shock indication where IABP use has been limited and in general not found to be of value unless it was for stabilizing the patient after a complication of PCI such as hemodynamic collapse.
T
It is therefore hard to ascribe what the association of lower IABP use and high mortality means from this
RI P
study. On the one hand it can suggest that non-cardiogenic shock PCI procedures have improved with less acute complications which have been seen in some settings. 7 On the other hand it could also mean
SC
that the incidence of cardiogenic shock is falling because of better and timelier primary PCI in AMI. 8 This is also possible as the majority of patients who develop cardiogenic shock do so later during the
NU
hospitalization after admission. 8 This is partially refuted by the small increase in patients with
MA
cardiogenic shock that had PCI from 0.88% to 1.19% observed in this study. This change of 0.31% suggests that there may have been a 35% increase in the incidence in cardiogenic shock over a 10-year period, which would seem rather large for a short period. Community-based studies from Massachusetts
ED
have shown that the prevalence of cardiogenic shock has remained relatively stable for the last several
PT
decades [6]. Thus it is uncertain if we can conclude much from this study about cardiogenic shock and
CE
PCI.
AC
There is also a possibility that hospitals have coded more patients as having cardiogenic shock over time. If this was done, it would lead to a lower observed mortality among patients with cardiogenic shock that also had PCI. This was indeed found where the mortality dropped from 22.8% to 17.8%. This would represent a 22% relative reduction in mortality during the 10-year period. As all these patients were treated with PCI that has been shown to lower mortality in cardiogenic shock, other factors must be at play. It would seem unlikely that we could attribute this finding to IABP use, as the IABP-SHOCK randomized trial showed no reduction in mortality either at 30-days or at 1 year with this therapy. 9 The ACTION registry is registering all AMI patients at 392 hospitals and has found a 4.3% to 12.5% rate of cardiogenic shock in STEMI and non-STEMI. 10 This would be the best source for detecting changes in the prevalence of AMI and cardiogenic shock over time. Unfortunately, that registry and the current NIS 3
ACCEPTED MANUSCRIPT administrative database only collect outcomes among patients while in the hospital. Both data sets would
RI P
T
benefit from connecting to long-term mortality data.
Interestingly, there is also evidence of changes in the prevalence of AMI among patients having PCI
SC
observed in this study. The rate of PCI in AMI rose by 18% from 2006 to 2008, for which no explanation
MA
fidelity to assess the prevalence of disease states.
NU
is provided. These findings in aggregate suggest that administrative databases may not have the optimal
What guidance can we then take from this study? There is still a great deal of uncertainty on how to best
ED
support patients with AMI complicated by cardiogenic shock. As this is one of the main causes of
PT
mortality in AMI, we must find better ways to manage these patients. The randomized SHOCK trial showed that revascularization lowered 1-year mortality. However, since that landmark study, we have
CE
not found other better treatment strategies. The use of IABP has undisputed hemodynamic benefit, while modest, in patients with cardiogenic shock. It may therefore still be reasonable to use IABP in this
AC
setting, even if it does not ultimately lower mortality. It is also recommended by the American Heart Association and American College of Cardiology practice guidelines as hemodynamic support in cardiogenic shock and heart failure. Recent devices such as hemo-pump and Impella have been applied in cardiogenic shock, but we lack adequately sized randomized trials to assess their benefit-to-risk ratio. Uniformly, these devices provide better hemodynamic support compared with IABP, but vascular and hemorrhagic complications tend to be higher. 11 Unfortunately, registries can help us better understand the devices in the clinical setting, but they are no substitute for adequately sized randomized clinical trials in cardiogenic shock, which can define the potential best support device to use. Only then can we hope to reduce mortality in cardiogenic shock with certainty.
4
ACCEPTED MANUSCRIPT References:
T
1. Chen EW, Canto JG, Parsons LS, et al, for the NRMI 2 Investigators. Relation Between Hospital
RI P
Intra-Aortic Balloon Counterpulsation Volume and Mortality in Acute Myocardial Infarction
SC
Complicated by Cardiogenic Shock. Circulation. 2003;108:951-7.
2. Curtis JP, Rathore SS, Wang Y, et al. Use and effectiveness of intra-aortic balloon pumps among
NU
patients undergoing high risk percutaneous coronary intervention: insights from the NCDR. Circ
MA
Cardiovasc Qual Outcomes. 2012;5:21-30.
3. Unverzagt S, Machemer MT, Solms A, et al. Intra-aortic balloon pump counterpulsation (IABP) for
PT
ED
myocardial infarction complicated by cardiogenic shock. Cochrane Database Syst Rev. 011;7:CD007398.
4. Thiele H, Zeymer U, Neumann FJ, et al, for the IABP-SHOCK II Trial Investigators. Intra-aortic
CE
balloon support for myocardial infarction with cardiogenic shock. N Engl J Med. 2012;367:1287-96.
AC
5. Patel et al. Am Heart J. 2014.
6. Goldberg RJ, Spencer FA, Gore JM, et al. Thirty-year trends (1975 to 2005) in the magnitude of, management of, and hospital death rates associated with cardiogenic shock in patients with acute myocardial infarction: a population-based perspective. Circulation 2009;119:1211-9.
7. Singh M, Rihal CS, Gersh BJ, et al. Twenty-five year trends in in-hospital and long-term outcome after percutaneous coronary intervention: a single-institution experience. Circulation. 2007;115:28352841.
5
ACCEPTED MANUSCRIPT 8. Jeger RV, Radovanovic D, Hunziker PR, et al, for the AMIS Plus Registry Investigators. Ten-year
T
trends in the incidence and treatment of cardiogenic shock. Ann Intern Med. 2008;149:618-626.
RI P
9. Thiele H, Zeymer U, Neumann FJ, et al, for the Intra-aortic Balloon Pump in cardiogenic shock II (IABP-SHOCK II) trial investigators. Intra-aortic balloon counterpulsation in acute myocardial infarction
SC
complicated by cardiogenic shock (IABP-SHOCK II): final 12 month results of a randomised, open-label
NU
trial. Lancet. 2013;382:1638-45.
MA
10. Anderson ML, Peterson ED, Peng SA, et al. Differences in the profile, treatment, and prognosis of patients with cardiogenic shock by myocardial infarction classification: A report from NCDR. Circ
ED
Cardiovasc Qual Outcomes. 2013 Nov;6(6):708-15.
PT
11. Cheng JM, den Uil CA, Hoeks SE, et al. Percutaneous left ventricular assist devices vs. intra-aortic balloon pump counterpulsation for treatment of cardiogenic shock: a meta-analysis of controlled trials.
AC
CE
Eur Heart J. 2009;30: 2102-2108.
6