The enormous success of ACE inhibitors in hypertension and heart failure spurred hope that adding a second drug to block the renin-angiotensin system would yield improved outcomes. Although definitive evidence supporting dual blockade of the renin-angiotensin system has never been found, more than 200,000 patients in the US currently receive this therapy. Now a large new meta-analysis suggests that dual blockade results in no improvement in mortality but is associated with an increase in important adverse events.
In a paper published online in BMJ, Harikrishna Makani and colleagues at Columbia University and New York University performed a meta-analysis of more than 68,000 patients who were enrolled in clinical trials comparing dual blockade of the renin-angiotensin system with monotherapy. They found no significant difference between the groups for all cause mortality or cardiovascular mortality, although dual blockade was associated with a signifcant 18% reduction in hospital admission for heart failure: