Association of Impaired Relaxation Mitral Inflow Pattern (Grade 1 Diastolic Function) With Long-Term Noncardiovascular and Cardiovascular Mortality.

Abstract

Background: Abnormalities of left ventricular diastolic function are established independent predictors of heart failure and mortality. The aim of this study was to determine whether the association of diastolic function with all-cause mortality is driven by cardiovascular or noncardiovascular death and if impaired relaxation mitral inflow filling pattern is a risk marker.

Methods: Diastolic function was graded by the Mayo Clinic algorithm using the well-characterized prospective Olmsted County Heart Function Study. Those with reduced left ventricular ejection fraction, moderate or greater valve disease, clinical diagnosis of heart failure, or indeterminate diastolic function were excluded. Notably, all patients with an impaired relaxation pattern (E/A ratio < 0.8) were classified as abnormal (grade 1) regardless of ejection fraction and clinical or other echocardiographic abnormalities. Individuals were followed for a median of 19.7 years (interquartile range, 18.9-20.6 years) for mortality outcomes.

Results: In a community cohort of 1,005 subjects 63 years (interquartile range, 57-71 years) of age, grade 1 diastolic function was common (26%) and associated with all-cause mortality (hazard ratio [HR], 4.05; 95% CI, 3.22-5.09; P < .0001). This association persisted in a subgroup of those with impaired myocardial relaxation and no other clinical or echocardiographic abnormalities (HR, 2.71; 95% CI, 1.89-3.88; P < .0001). The association of diastolic function with noncardiovascular death was not significant after adjustment for age, sex, and comorbidities, though there was an association with grade 1 diastolic function and risk for death of dementia (age- and sex-adjusted HR, 2.30; 95% CI, 1.54-3.45; P < .001). The association of diastolic function and cardiovascular mortality persisted in multivariable model, including for grade 1 diastolic function (HR, 2.43; 95% CI, 1.16-5.05; P = .02).

Conclusions: Impaired relaxation mitral inflow pattern (grade 1) is common in older adults in the community and found to be associated with cause-specific death, highlighting this simple echocardiographic finding as a potential biomarker of cardiovascular and cognitive risk and not necessarily a benign finding that is normal with age.