Myocardial Infarction: prophylactic intraaortic balloon counterpulsation did not decrease mortality and increased stroke.

Clinical bottom line (level 1b)

  1. Patients given prophylactic intraaortic balloon counterpulsation had no clear difference in death, reinfarction, infarct-related artery reocclusion and heart failure or sustained hypotension.
  2. High risk patients with acute myocardial infarction treated with primary angioplasty and given prophylactic intraaortic balloon counterpulsation were more likely to have a stroke than those given conservative, traditional care (NNH = 42 at unknown) .
Stone et al: Journal of the American College of Cardiology 1997; 29: 1459-1467
Expires December 2003

The study

Unblinded ?concealed randomised trial with intention-to-treat
Setting: 34 institutions, North and South America, Europe and Japan

437 patients (aged mean 64 years, 75% male) ongoing chest pain up to 12 hours in duration with ECG evidence of acute myocardial infarction, having received primary angioplasty and still at high risk of further cardiovascular events.

Excluded if
  • cardiogenic shock
  • bleeding diathesis prohibiting the use of aspirin or heparin
  • precatheterisation administration of thrombolytic therapy


Note:
  • Patients were stratified into high and low risk groups on the basis of clinical and angiographic variables. Patients were considered to be high risk if one or more of the following were met: age >70 years, three-vessel disease, left ventricular ejection fraction < or = 45%, vein graft occlusion, persistent malignant ventricular arrhythmias or a suboptimal percutaneous transluminal coronary angioplasty. High risk patients were randomised to intraaortic balloon counterpulsation.


Control Group: (n = 226, 226 analysed): conservative, traditional care
Experimental Group: (n = 211, 211 analysed): intraaortic balloon pump counterpulsation for 36 to 48 hours
All patients were treated with 324 mg of chewable soluble aspirin, a 5000-10000 units bolus of intravenous heparin, intravenous nitroglycerin and , in the absence of contraindications, intravenous followed by oral beta-blockade.
100% followed for ?

The evidence

Outcome Time to outcome CEREERRRR
(95% CI)		ARR
(95% CI)		NNT
(95% CI)
stroke weeks 0
(0.00%)		 5
(2.37%)		 -100%
(% to %)		 -2.37%
(-4.42% to -0.32%)		 -42
(-315 to -23)
death unknown 7
(3.11%)		 9
(4.27%)		 -37.0%
(-262% to 48.0%)		 -1.15%
(-4.70% to 2.39%)		 -87
(NNT = 21 to infinity;
NNH = 42 to infinity)
reinfarction unknown 18
(8.00%)		 13
(6.16%)		 23.0%
(-53.0% to 61.0%)		 1.84%
(-2.97% to 6.64%)		 54
(NNT = 34 to infinity;
NNH = 15 to infinity)
infarct-related artery reocclusion unknown 12
(5.33%)		 14
(6.64%)		 -24.0%
(-163% to 41.0%)		 -1.30%
(-5.76% to 3.16%)		 -77
(NNT = 17 to infinity;
NNH = 32 to infinity)
heart failure or sustained hypotension unknown 52
(23.1%)		 42
(19.9%)		 14.0%
(-24.0% to 40.0%)		 3.21%
(-4.50% to 10.9%)		 31
(NNT = 22 to infinity;
NNH = 9 to infinity)

Comments

  1. Intraaortic balloon pump counterpulsation was performed in 86% of patients randomised to it.

Citation

  1. Stone GW, Marsalese D, Brodie BR, et al: A prospective, randomized evaluation of prophylactic intraaortic balloon counterpulsation in high risk patients with acute myocardial infarction treated with primary angioplasty. Journal of the American College of Cardiology 1997; 29: 1459-1467
Contributor: Clare Wotton and Bob Phillips, December 1999
Reviewer:

Clinical Question.
Patient high risk patients with acute MI
Intervention or Exposure prophylactic intraaortic balloon counterpulsation
Comparison conventional treatment
Outcome reinfarction