Risk assessment that includes echocardiography is a much better predictor of adverse cardiovascular events in older patients over a 5-year span than assessment only with clinical factors, according to an article in the October 1st issue of the Journal of the American College of Cardiology. Adverse outcomes included myocardial infarction, onset of atrial fibrillation, onset of heart failure, need for revascularization procedure, stroke, transient ischemic attack, and cardiac mortality.

"The key finding is that a non-invasive echocardiogram provides a wealth of information that cannot be obtained from just clinical history or physical examination alone, and such information is useful in understanding the risk of an individual for the first undesirable age-related event," said Teresa S. M. Tsang, MD, lead author of the study.

The American researchers reviewed the records of 1,160 patients 65 years of age or older who were referred for an echocardiogram at a major medical center. None of the patients had ever had atrial fibrillation, myocardial infarction, heart failure, stroke, transient ischemic attack, or a revascularization procedure at the time of the baseline ultrasound examination.

During follow-up (average, nearly 4 years), almost one third of patients had an adverse cardiovascular event or died from cardiac-related causes. The most useful clinical and echocardiogram information in predicting risk of included 4 clinical factors (age, gender, and presence or absence of diabetes and hypertension) and 4 cardiac ultrasound findings (presence or absence of left atrial enlargement and increased left ventricular mass, normal or abnormal ejection fraction, and normal or abnormal cardiac relaxation and compliance).

From these considerations, the researchers devised a formula that predicted the risk of the outcome events of interest in the study. The older patients classified as low-risk had a 90 percent chance of surviving 5 years without any of the outcome events. In contrast, patients in the high-risk group had a 50 percent chance for an event (including death) within 5 years.

The patients in the study were referred for echocardiography because of symptoms such as shortness of breath, chest discomfort, cardiac arrhythmia, light-headedness or faintness, or heart murmur.

"Symptoms are often subjective and can be nonspecific, and often times, difficult to quantify. They did not appear to be very good predictors of outcome events for these older individuals. Echocardiography provides more objective and quantifiable information, and appeared to be more helpful in predicting which patients are likely to have the untoward events," Tsang said.

"The clinical implications could be enormous. With the age-associated public health problems that we are confronting, and the anticipated continued increase in the number of people living to older age, it is important to identify simple, non-invasive, and hopefully also cost- effective ways of recognizing individuals who have not had a first event, but are at significant risk of any of the first events that we looked at in the study," Tsang added.

Tsang recommended prospective studies to establish a place for echocardiography in risk assessment of older patients.

Pamela S. Douglas, MD, wrote in an editorial that "the finding that left atrial size is related to prognosis is new and of interest." Douglas noted that the patients in the current study were a mostly homogenous group of individuals all seen at the same clinic, so the findings will need to be replicated in other settings. Nevertheless, she welcomed the progress toward refining how ultrasound could be used to predict risk.

"The important points are that significant health risks can be predicted by medical tests as well as by risk factors. In fact, medical tests such as echo provide more information than simple risk factors. Since most of these risks are modifiable, or can be reduced, regular health care is important--over and above just knowing that you are at risk. Of course, patients need to take ownership of risk and pursue a healthy life style to reduce it," Douglas said.