I just ran across an article recently that has numerous suggestions, based on recent clinical trials. Among them are celery, works within one week. Olive leaf extract, 500mg twice a day, showed excellent results. Hawthorn berry, garlic, onion, carrot, as well as radish showed some improvement, as well as mistletoe but probably hard to find. If you are taking a blood pressure med, check your BP often, because combining herbs with low blood pressure meds may lower it too much.
olive leaf study http://www.ncbi.nlm.nih.gov/pubmed/21036583
The article about herbs to lower BP:
Good results have been reported with Hawthorn from consumers. Garlic, which has been marketed as a wonder herb for BP, shown modest results.
hope this helps.
For other heart health recommendations read my article about heart health. Which I need to update since I ran across this info.
Hope it helps, let us know