Do We Need MRI Monitoring of Carotid Atherotic Plaque to Assess Statin Treatment?
Posted Oct 18 2011 12:00am
I continue to be impressed by the ability of cardiologists to both control many of their own imaging studies and also to generate ideas for new types of cardiovascular imaging studies. A case in point is a recent article discussing the use of MRIs to assess the response of carotid artery atheromas to treatment with a statin (see: Cholesterol therapy monitoring with MRIs could improve outcomes ). Below is an excerpt from the article:
MRI scanning could become a powerful new tool for assessing how well cholesterol drugs are working, according to ...cardiologist Binh An P. Phan, MD. Phan is co-author of an MRI study of patients who had recently begun taking cholesterol medications. The study found that intensive treatment with cholesterol drugs significantly reduced the amount of cholesterol in artery-clogging plaque....Imaging technologies traditionally used to monitor cardiovascular disease, such as angiograms and ultrasounds, show the overall size of the plaque buildup. In the new study, MRI scans were more precise, showing the amount of cholesterol within the plaque....The scans were done on patients’ carotid arteries in the neck, rather than on their coronary arteries. Carotid arteries are easier to image because they are closer to the surface of the body, and do not move as much as coronary arteries of a beating heart. Since atherosclerosis occurs in blood vessels throughout the body, plaque buildup in carotid arteries is a good representation of what is occurring in coronary arteries.The findings confirmed the researchers’ hypothesis that the reason why cholesterol medications shrink the overall size of the plaque is because cholesterol is being removed from within the plaque. Thus, using MRI scans to monitor the amount of cholesterol in plaque may help doctors to better determine how well cholesterol medications are working. If an MRI showed cholesterol was not being reduced, more aggressive therapy might be needed, [the author of the study ]said.
Statins are very effective in reducing the level of serum cholesterol. Cholesterol and lipids are frequently contained within arterial atheromas. Intensive treatment of high cholesterol levels can thus reduce the size of atheromatous plaques. MRI scanning of the carotid arteries can document a reduction in size of such plaques. However, do we need to document this drug effect with such an expensive imaging procedure or is it sufficient to monitor the effectiveness of statin therapy with serum cholesterol levels? Is this an example of diagnostic overreaching? I am sure that the author of this study can cite cases where serum cholesterol levels do not accurately reflect the degree of atherosclerosis in the carotid artery. However, the real issue in my mind is whether we necessarily need to turn to the most expensive and technologically advanced diagnostic procedure in order to draw conclusions about the clinical status of a patient.
I continue to be impressed by the ability of cardiologists to both control many of their own imaging studies and also to generate ideas for new types of cardiovascular imaging studies. A case in point is a recent article discussing the use of MRIs to assess the response of carotid artery atheromas to treatment with a statin (see: Cholesterol therapy monitoring with MRIs could improve outcomes ). Below is an excerpt from the article:
MRI scanning could become a powerful new tool for assessing how well cholesterol drugs are working, according to ...cardiologist Binh An P. Phan, MD. Phan is co-author of an MRI study of patients who had recently begun taking cholesterol medications. The study found that intensive treatment with cholesterol drugs significantly reduced the amount of cholesterol in artery-clogging plaque....Imaging technologies traditionally used to monitor cardiovascular disease, such as angiograms and ultrasounds, show the overall size of the plaque buildup. In the new study, MRI scans were more precise, showing the amount of cholesterol within the plaque....The scans were done on patients’ carotid arteries in the neck, rather than on their coronary arteries. Carotid arteries are easier to image because they are closer to the surface of the body, and do not move as much as coronary arteries of a beating heart. Since atherosclerosis occurs in blood vessels throughout the body, plaque buildup in carotid arteries is a good representation of what is occurring in coronary arteries.The findings confirmed the researchers’ hypothesis that the reason why cholesterol medications shrink the overall size of the plaque is because cholesterol is being removed from within the plaque. Thus, using MRI scans to monitor the amount of cholesterol in plaque may help doctors to better determine how well cholesterol medications are working. If an MRI showed cholesterol was not being reduced, more aggressive therapy might be needed, [the author of the study ]said.Statins are very effective in reducing the level of serum cholesterol. Cholesterol and lipids are frequently contained within arterial atheromas. Intensive treatment of high cholesterol levels can thus reduce the size of atheromatous plaques. MRI scanning of the carotid arteries can document a reduction in size of such plaques. However, do we need to document this drug effect with such an expensive imaging procedure or is it sufficient to monitor the effectiveness of statin therapy with serum cholesterol levels? Is this an example of diagnostic overreaching? I am sure that the author of this study can cite cases where serum cholesterol levels do not accurately reflect the degree of atherosclerosis in the carotid artery. However, the real issue in my mind is whether we necessarily need to turn to the most expensive and technologically advanced diagnostic procedure in order to draw conclusions about the clinical status of a patient.