Due to concerns about international differences in treatment effectiveness, many countries are reluctant to extrapolate overseas clinical data to form the basis of guideline recommendations and intervention approval processes. The evidence on which these concerns are based, however, comes from a limited dataset, with few studies directly assessing international differences in treatment effectiveness. This study aims to assess differences in the results of cardiovascular trials between Europe, North America, and Asia using the panoramic meta-analysis approach. All meta-analyses containing randomised control trials for the treatment or prevention of cardiovascular diseases were searched for in The Cochrane Library (2000 to 2008) and Medline (2005-2008). Analysis was then conducted within and over the included meta-analyses by performing pair-wise comparisons of the trial results between Europe and North America, Europe and Asia, and North America and Asia and a universal comparison of all three continents’ trial results together. All analyses were conducted over fatal and non-fatal endpoints. The findings suggested that for both endpoints, interventions performed best in Asian trials. For fatal endpoints, a high proportion of positive trial results were observed for Japan. Further investigation showed that between-continent differences in treatment effect could be explained by between-continent differences in trial quality. However, the types of intervention prone to inter-continental differences could not be identified for fatal or non-fatal endpoints. These findings suggest that those developing guidelines and approving interventions should be cautious when extrapolating overseas data. In particular, this study highlights the importance of taking trial quality into account when extrapolating and interpreting clinical trial data from different regions.