Thank you for your question! Regarding Clinidipine; it is in the same pharmacological category with Amlodipin (calcium channel blockers); it is a drug developed by Japan pharmaceutical companies; its primary use is treatment of hypertension, not for arrhythmia; it is demonstrated effective in reducing blood pressure, but further studies in patients need to be done in order to be approved by the american FDA (Food and Drug Administration); according to side effects it has almost the similar profile as Amlodipin ( causes peripheral edemas in about 16% of patients treated with it (5-20 mg). Usually it is taken 1 dose per day. On the other side Amlodipin has been studied more profoundly and is now well known for its antihypertensive effect. Nevertheless I don t think that both of them affect the occurrence of arrhythmia; so to focus on your stress test results, I think that the presence of complex arrhythmia during stress test in accordance with other clinical (chest discomfort, etc) or ECG findings (ST segment depressions, etc) should raise the suspicion towards relapsing ischemic problems; you have now almost 13 years from your By pass, and your vein grafts probably used ( you had triple By pass) should be checked with more scrutiny for their patency; In that case I recommend you to perform a coronary angiography which is a routine protocol in so many years after CABG. Hope to have been helpful to you; Best wishes from Dr. Iliri