Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels in the blood and reduce the risk of heart disease [3]. According to the sources provided, there is no specific information regarding how long Lipitor affects heart rate. However, it is known that Lipitor and other statins can have side effects, including changes in heart rate [2]. Statins work by blocking an enzyme in the liver that produces cholesterol, which can also affect the production of other substances in the body [2]. These changes can sometimes lead to side effects, such as muscle pain, digestive problems, and changes in heart rate [2][3].

It is important to note that not everyone who takes Lipitor will experience side effects, and the severity and duration of any side effects can vary from person to person [3]. If you have concerns about how Lipitor may be affecting your heart rate or any other aspect of your health, it is recommended that you speak with your doctor or healthcare provider [2][3].

Sources:
[2] British Heart Foundation. (n.d.). Statins. https://www.bhf.org.uk/informationsupport/heart-matters-magazine/medical/drug-cabinet/statins
[3] Mayo Clinic. (2021, January 15). Atorvastatin (Oral Route) Side Effects. https://www.mayoclinic.org/drugs-supplements/atorvastatin-oral-route/side-effects/drg-20067003
[4] DrugPatentWatch. (n.d.). Lipitor. https://www.drugpatentwatch.com/p/tradename/LIPITOR