This article is more than 5 years old. Information may no longer be current.
Higher valvuloarterial impedance linked with poorer outcomes in setting of aortic stenosis
Click Here to Manage Email Alerts
Increased valvuloarterial impedance was a marker for excessive left ventricular hemodynamic load in patients with aortic stenosis.
Researchers analyzed clinical and echocardiographic data of 544 consecutive asymptomatic patients with at least a moderate aortic stenosis. Researchers assigned patients to either a low (n=172), medium (n=192) or high valvuloarterial impedance group (n=180). The primary study endpoint was overall death, despite whether patients had aortic valve replacement.
Overall, there were 91 deaths in the study population, with 15 (9%) in the low impedance group, 36 (19%) in the medium impedance group and 40 (22%) in the high impedance group. The researchers reported that four-year survival was lower in patients with a high baseline valvuloarterial impedance (65%) compared with those with medium impedance (78%) and low impedance (88%; P<.001).
Survival was also lower in the medium impedance group compared with the low impedance group (P=.007). Mortality increased by 1.41-fold (95% CI, 1.17-1.67) per 1-U increase in valvuloarterial impedance in a univariate analysis and by 1.36-fold (95% CI, 1.03-1.75) in multivariate analysis. A multivariate analysis revealed that independent risk factors for mortality were older age, increased LV mass index and increased valvuloarterial impedance. The risk for mortality was increased by 2.76-fold (95% CI, 1.32-5.92) in patients with high valvuloarterial impedance and by 2.30-fold (95% CI, 1.16-4.71) in patients with medium valvuloarterial impedance when other risk factors and types of treatment were adjusted.
“Increased valvuloarterial impedance is a marker of excessive LV hemodynamic load and identifies patients with a poor outcome,” the researchers concluded. “These findings suggest that beyond standard indexes of stenosis severity, LV geometry and function, the consideration of valvuloarterial impedance may be useful to improve risk stratification and clinical decision-making in patients with arterial stenosis.”
Hachicha Z. J Am Coll Cardiol. 2009;54:1003-1011.