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CardioScan Detects Coronary Artery Plaque Despite Good HDL Cholesterol Levels in Women The WHISPER Study Cardiovascular disease is the number one cause of death in women. Women are more likely to die from their first heart attack than men, and 60 percent of sudden cardiac death occurs in the absence of warning symptoms or a known history of coronary artery disease (CAD), hence the catch phrase, "The Silent Epidemic." Traditional risk factors related to the development of plaque in the coronary arteries of women include age, menopause, family history of premature CAD, nicotine abuse, abnormal cholesterol, high blood pressure and diabetes. Over 80 percent of heart attacks can be prevented and an estimated 100,000 lives could be saved each year if we used aggressive primary prevention with strict risk factor modification. Coronary artery calcification represents the presence of calcified plaque in the vessel walls supplying blood to the heart. The calcium burden correlates with the severity of plaque and is felt to be an early predictor of cardiovascular events, including heart attack and sudden cardiac death. A special type of CT scan, also known in our office as the CardioScan, has the ability to quantify the amount of calcified plaque in the coronary arteries and provides a calcium score. A normal score is zero. This has been primarily investigated as a tool to predict the probability of CAD and predict risk for future coronary events. Although soft plaque which has not calcified may not be detected, the CardioScan may detect calcified plaque before it shows up on a stress test. Furthermore, declines in calcium scores have been correlated with the reduction of LDL (bad) cholesterol. This could challenge the threshold to initiating cholesterol lowering medicines, even in the setting of excellent HDL (good) values and normal total cholesterol to HDL ratios, which is seen more often in women than men. The WHISPER (Women's Hearts: Ischemic Screening with Proactive Evaluation and Recommendations) study was designed to identify women without a history of cardiovascular disease, but who are at increased risk for future heart attacks and to prospectively follow them over time. In this study, women between the ages of 45 to 65 who had more than two unmodified risk factors and a recent normal nuclear stress test were considered. CardioScan imaging was then performed to identify the presence of coronary artery plaque not detected by nuclear stress tests and to monitor its progression during a two-year risk modification program. Risk factors are monitored, including success in blood pressure and cholesterol control as well as weight loss. A repeat CardioScan is performed in two years and compared to the baseline and the impact of interval risk factor modification will be addressed. One hundred women have been enrolled into WHISPER. Despite normal stress tests, an unexpected 42 percent have coronary artery plaque as detected by the CardioScan! Furthermore, the majority have excellent HDL (good) cholesterol and normal total/HDL ratios. The LDL (bad) cholesterol is elevated, but has been untreated prior to this study due to a common perception that a high HDL is protective against coronary plaque! The results of the baseline WHISPER enrollment were selected for poster presentation at the American Heart Association Annual Scientific Meeting in New Orleans and received acknowledgement in the session as one of the top five clinical studies! The two-year follow-up studies will be completed in March 2006. Tracy L. Stevens, M.D. © 2005, Cardiovascular Consultants. |
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