Research has shown that the risk of some heart and blood vessel problems may be higher with diclofenac (when taken by mouth) than with some alternative anti-inflammatories.
You should speak to your GP or pharmacist at your next routine appointment or visit if you are taking diclofenac (tables, capsules, or suppositories) and you have a condition such as heart failure, other heart disease (eg, angina), circulatory problems causing leg pain, or if you have had a heart attack or stroke.
Information for patients can be found here