ASE: Hand-Held Echo Aids Outpatient Cardiac Risk Assessment

SEATTLE, June 22 -- A hand-held echocardiography device can bring cardiac imaging to the outpatient setting, said investigators here.
In a multivariate analysis, left atrial volume determined by echo with the five-pound device, during a year of follow-up, predicted the risk of cardiovascular events beyond the scope of clinical history and physical exam, said Grace Verzona, M.D., of the Mayo Clinic in Rochester, Minn.
The device produced satisfactory imaging results in 94% of cases in exams that averaged 11 minutes, she reported at the American Society of Echocardiography meeting here.
"This hand-held echo device is very efficient for cardiovascular risk stratification in the outpatient setting," said Dr. Verzona. "The information on left atrial volume was incremental to age and risk factors for prognostication in older adults."
Although the ability to acquire anatomical and physiologic information in the outpatient setting could improve risk assessment, the feasibility of using hand-held echo for outpatient cardiovascular prognostication had not been evaluated, she pointed out.
So Mayo investigators evaluated the device in 423 geriatric patients (mean age 73 years) seen in outpatient clinics. None of the patients had a history of heart valve disease or cardiovascular events. The device was used to perform 11 measurements related to four echocardiographic parameters found to be incremental to risk-factor assessment and predictive of cardiac outcomes:
Left-ventricular mass
Left-ventricular diastolic function
Left-ventricular ejection fraction
Left atrial volume
The patients were prospectively followed for a year, and the primary endpoints were first cardiovascular even or cardiovascular death.
During 12 months of follow-up, 28 patients had first clinical events (seven MIs, three strokes, 10 coronary revascularizations, two cases of atrial fibrillation, three cases of new congestive heart failure, and three cardiovascular deaths).
In an analysis of variables associated with clinical events, left-atrial volume was the only factor that differed between patients with and without clinical events. Patients with clinical events had a mean left- atrial volume of 33 mL/m2 compared with 30 mL/m2 in patients who did not have clinical events (P=0.04). Multivariate analysis revealed three factors (two of them echo-related) that independently predicted an increased risk of clinical events:
History of coronary artery disease (P=0.008)
Mitral valve E/A wave ratio > 1.5 (P=0.037)
Indexed left-atrial volume (P=0.013)
"This hand-held echo device is particularly useful in the evaluation of geriatric patients because the likelihood of finding a potential problem increases with the patient's age," said Dr. Verzona. "By using hand-held echo, a physician can follow a patient more closely, initiate therapy if indicated, or refer a patient to a specialist if that's indicated."