Outcomes among valvular heart disease patients experiencing ischemic stroke or transient ischemic attack in Olmsted County, Minnesota

Abstract

Objective: To estimate the rates and predictors of survival and recurrence among residents of Olmsted County, Minnesota, who received an Initial diagnosis based on 2-dimensional color Doppler echocardiography of moderate or severe mitral or aortic stenosis or regurgitation and who experienced a first ischemic stroke, transient ischemic attack (TIA), or amaurosis fugax.

Patients and methods: At the Mayo Clinic in Rochester, Minn, we used the resources of the Rochester Epidemiology Project to identify Individuals who met the criteria for inclusion in the study and to verify exclusion criteria. The study included all residents of Olmsted County, Minnesota, who experienced a first Ischemic stroke, TIA, or amaurosis fugax within 30 days of or subsequent to receiving a first-time 2-dimensional color Doppler echocardlography-based diagnosis of moderate or severe mitral or aortic stenosis or regurgitation between January 1, 1985, and December 31, 1992. The Kaplan-Meier product-limit method was used to estimate the rates of subsequent stroke and death after the ischemic stroke, TIA, or amaurosis fugax. The Cox proportional hazards model was used to assess the effect of several potential risk factors on subsequent stroke occurrence and death.

Results: For the 125 patients in the study, the Kaplan-Meier estimates of the risk of death and the risk of stroke at 2-year follow-up were 38.6% (95% confidence interval [CI], 29.9%-47.5%) and 18.5% (95% CI, 10.0%-27.0%), respectively. Compared with the general population, death rates were significantly Increased (standardized mortality ratio = 1.75; 95% CI, 1.38-2.19; P < .001) but rates of subsequent stroke occurrence were not (standardized morbidity ratio = 1.20; 95% CI, 0.75-1.84; P = .40). After adjustment for age, sex, and cardiac comorbidity, neither the type nor severity of valvular heart disease was an independent determinant of survival or subsequent stroke occurrence.

Conclusions: Patients with mitral or aortic valvular heart disease who experience Ischemic stroke, TIA, or amaurosis fugax have Increased rates of death, but not recurrent stroke, compared with expected rates. Other cardiovascular risk factors are more important determinants of survival In these patients than the type or echocardiographic severity of the valvular heart disease.