Left atrial volume in the prediction of first ischemic stroke in an elderly cohort without atrial fibrillation.
OBJECTIVE
To determine the clinical importance of left atrial (LA) volume in the prediction of first ischemic stroke.


METHODS
This retrospective cohort study included randomly selected residents of Olmsted County, Minnesota, aged 65 years or older, who had undergone transthoracic echocardiography at least once at the Mayo Clinic in Rochester, Minn, between January 1, 1990, and December 31, 1998, were in sinus rhythm, and had no history of stroke, transient ischemic attack, atrial fibrillation, or valvular heart disease. Patients were monitored through medical records for first ischemic stroke or death.


RESULTS
Of 1554 residents (59% women) aged 75+/-7 years, 92 (6%) had experienced at least 1 ischemic stroke over 4.3+/-2.7 years (incident stroke rate, 1.4 per 100 person-years). Left atrial volume of 32 mL/m2 or greater (hazard ratio [HR], 1.63; confidence interval [CI], 1.08-2.46) was independent of age (HR, 1.04; CI, 1.02-1.07), diabetes (HR, 1.91; CI, 1.07-3.41), myocardial infarction (HR, 1.64; CI, 1.01-2.64), and hyperlipidemia (HR, 1.55; CI, 1.01-2.37) for the prediction of first ischemic stroke. When quartiles of LA dimension were plotted against quartiles of indexed LA volume, a stepwise increase in risk with each quartile increment was evident only for indexed LA volume. Also, an LA volume of 32 mL/m2 or greater was associated with an increased mortality risk (HR, 1.30; CI, 1.09-1.56), independent of age, sex, and stroke status.


CONCLUSIONS
In our elderly cohort with no prior atrial fibrillation, LA volume was independently predictive of first ischemic stroke, incremental to age, diabetes, myocardial infarction, and hyperlipidemia. It was also an independent predictor of death.
Barnes
Marion E
ME
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minn 55905, USA.
Miyasaka
Yoko
Y
Seward
James B
JB
Gersh
Bernard J
BJ
Rosales
A Gabriela
AG
Bailey
Kent R
KR
Petty
George W
GW
Wiebers
David O
DO
Tsang
Teresa S M
TS
D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000150:complications; D016279:Atrial Function, Left; D002545:Brain Ischemia / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality / Q000503:physiopathology; D002306:Cardiac Volume; D004452:Echocardiography / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008910:Minnesota / Q000453:epidemiology; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016037:Single-Blind Method; D020521:Stroke / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality / Q000503:physiopathology; D016019:Survival Analysis