EKG Readings Can be Wrong
Reported November 19, 2009
(Ivanhoe Newswire) -- Measurements on the electrocardiogram (EKG) can
often mislead physicians into diagnosing the heart condition left
ventricular hypertrophy (LVH), requiring further screening tests before a
definitive conclusion can be reached.
A study of 500 patients found a false positive reading of between 77 and 82
percent in patients screened by EKG, and a false negative reading between 6
and 7 percent in the same patient population. The EKG also showed a high
negative predictive reading, which reflects the absence of LVH.
Researchers compared patientsí EKG data with coronary CT scans, which are
considered highly accurate for diagnosing LVH. An EKG, measures electrical
activity of a heartbeat; a CT scan produces clear, detailed images of the
"The EKG criteria for diagnosing left ventricular hypertrophy have a very
poor sensitivity," Mohamad Sinno, M.D., cardiology fellow at Henry Ford
Hospital and lead author of the study, was quoted as saying. "So when the
EKG shows left ventricular hypertrophy, it doesn't allow the physician to
make an accurate assessment, and further screening tools such as cardiac CT,
MRI scan, or an echocardiogram are warranted."
LVH, a condition in which the lower-left chamber of the heart grows
abnormally thick, affects more than 16 percent of the adult population in
the United States. It is caused by an underlying medical condition, most
commonly high blood pressure, but frequently symptoms do not manifest until
late in the disease process. Left untreated, LVH is an independent predictor
of serious or fatal cardiovascular disease.
SOURCE: Presented at the American Heart Association Annual Scientific
Conference, Orlando, FL, November 14-18, 2009