Calcium channel blockers for pulmonary arterial hypertension

Background

The blood pressure in the arteries of the lungs is normally much lower than the blood pressure in the rest of the body. Pulmonary hypertension occurs when the pulmonary arterial pressure gradually rises which causes damage to the heart, and can finally lead to heart failure and death. Calcium channel blockers are drugs which can relax the pulmonary arteries and decrease resistance and pressure of these vessels; this may benefit patients with pulmonary hypertension.

What we did

We searched for randomised controlled trials (RCTs) comparing calcium channel blockers with placebo.

What we found

We found only one trial. This trial has not been published in full and instead was presented as an abstract at a conference. Therefore we had only limited data from this trial to consider. The trial assessed the use of calcium channel blockers for pulmonary hypertension and did not reveal any improving effect on patient's exercise capacity (a primary outcome of this review) by calcium channel blocker.

We believe more research is needed, specifically RCTs should be done on this topic. This is because evidence from several non-randomized controlled studies suggest possible benefits, but we cannot be certain without RCTs.

Authors' conclusions: 

Currently, as there is lack of valid evidence, the efficacy and safety of CCBs is unproven in the treatment of PAH. However, the search strategy used for this review did identify four controlled clinical trials without randomization, three of which suggested treatment with CCBs may be beneficial in PAH. No adverse side effects of CCBs were reported. Confirmation of these findings by RCTs is recommended.

Read the full abstract...
Background: 

Pulmonary arterial hypertension (PAH) is one of several forms of pulmonary hypertension: a chronic disease of the pulmonary vasculature. The mean age at diagnosis is around 50 years old, with increasing prevalence in people over 70 years old (10% to 17%). The median survival to be approximately seven years with one-, three-, five-, and seven-year survival rates from time of diagnostic right-sided heart catheterization were 85%, 68%, 57%, and 49%, respectively. Several studies showed that calcium channel blockers (CCBs) reduce right ventricular hypertrophy and improve long-term haemodynamics in PAH.

Objectives: 

To evaluate the clinical efficacy and harms of CCBs for people with PAH.

Search strategy: 

The search strategy was provided by the Cochrane Airways Group Trials Search Co-ordinator. The following databases were searched from their inception until September 2014: the Cochrane Airways Group Register of Trials (CAGR); the Cochrane Central Register of Controlled Clinical Trials (CENTRAL) (The Cochrane Library,Issue 8 2014); MEDLINE (1948 to September 2014); EMBASE (1974 to September 2014); ClinicalTrials.gov; WHO trial portal; the Chinese Biomedical Databases (1979 to September 2014); CNKI: the Chinese Journals Full Text Database (1979 to September 2014), the Chinese Journals Full Text Database Century Journals (1979 to September 2014), the Chinese Doctoral Degree Thesis Full Text Database (1979 to September 2014), the Chinese Outstanding Master Degree Thesis Full Text Database (1979 to September 2014); VIP Database (1989 to September 2014) and WANFANG Database (1993 to September 2014). No language restriction was applied.

Selection criteria: 

Fully published randomized controlled trials (RCTs) comparing CCBs with placebo or other treatment, or comparing CCBs as an adjunct to other treatments with other treatments alone, in patients with PAH.

Data collection and analysis: 

We used standard methods expected by Cochrane.

Main results: 

We found one RCT to include in this review but it was published only in abstract form with no data for evaluation.