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Acute coronary syndrome

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Clinical features
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Therapy

Give intravenous a or buccal nitroglycerin for chest pain 
(if intravenous give 1 mg/ml; titrated from 1.5 ml/hour to 12 ml/hour. If 20% reduction in blood pressure or 10% decrease in heart rate, or headache, stop titration at that level.) a  

Why?

  • Intravenous nitroglycerin reduces ongoing ischaemia and use of sublingual nitroglycerin , but intolerable headaches and hypotension are common. There is no clear effect on mortality a or myocardial infarction. a

Intravenous nitroglycerin reduces ongoing ischaemia , but can cause intolerable side-effects

Patient Treatment Comparison Outcome CER RRR
(95% CI)		 NNT
(95% CI)
unstable angina a intravenous nitroglycerin placebo ongoing ischaemia
at 48 hours 		36% 50%
(11% to 72%) 		6
(3 to 27)
      use of > 2 tablets of sublingual nitroglycerin
at 48 hours 		31% 48%
(11% to 72%) 		7
(3 to 84)
      intolerable side-effects
at 48 hours 		0.0% %
 -10
(-35 to -6)
  • Buccal nitroglycerin causes fewer side effects than intravenous nitroglycerin. There is no clear difference on either the frequency of painful episodes or the need for emergency revascularisation. a

Buccal nitroglycerin causes fewer side effects than intravenous nitroglycerin

Patient Treatment Comparison Outcome CER RRR
(95% CI)		 NNT
(95% CI)
unstable angina a buccal nitroglycerin intravenous nitroglycerin side-effects
at 7 days 		75% 49%
(-8% to 76%) 		3
(1 to 38)

 

Expiry date: June 2003
Levels of Evidence used in grading these guides

Authors   CM   Ball , N   Shenker
Reviewer   I K   Jang
CAT Writers   N   Shenker , CJ   Wotton , CM   Ball , RS   Phillips