Background: Stable angina pectoris is a common condition, worldwide. Traditional Chinese herbal products (TCHP) are developed for treating stable angina pectoris in China.
Objectives: To assess the effectiveness and safety of TCHP in patients with stable angina.
Search strategy: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2006), MEDLINE (1995 to June 2008), EMBASE (1995 to June 2008), the Chinese Biomedical Database (CBM) (1995 to June 2008), Chinese Science and Technique Journals Database (VIP) (1994 to June 2008) and Chinese National Knowledge Infrastructure (CNKI) (1995 to June 2008). We handsearched the relevant Chinese journals. We also contacted researchers in the field and authors of studies evaluated in this review for more information. No language restrictions were applied.
Selection criteria: Randomised controlled trials comparing TCHP with placebo, various other TCHP preparations, or with other regimes commonly used currently in the treatment of stable angina.
Data collection and analysis: Quality of studies was assessed independently by two authors. Data were extracted by one author and checked by the other one.
Main results: Three studies each with the number of participants ranging from 60 to 80, and a total of 216 participants, were included in this review. The interventions used in the included studies were different from one another. One study compared TCHP with nitrates and was of good methodological quality whereas the remaining two trials compared one preparation with another preparation and one was of poor methodological quality. As such, we were unable to perform a summary meta-analysis. Only one trial with small patient numbers showed positive results favouring TCHP treatment compared with nitrates, in improved angina symptoms. Two of the trials stated that adverse reactions occurred but detailed data could not be obtained.
Authors' conclusions: There is currently insufficient evidence for effectively treating stable angina pectoris with any of the examined TCHP in this review, due to the small number of included studies and participants. Therefore, TCHP should be used with caution. High quality randomised trials with similar interventions are required to strengthen the evidence for the effectiveness and safety of Chinese medicinal herbs in angina pectoris.