Natriuretic Peptides in Severe Aortic Stenosis - Role in Predicting Outcomes and Assessment for Early Aortic Valve Replacement

Abstract

The natriuretic peptides are a group of endogenous, structurally related hormones with natriuretic, diuretic and peripheral vasodilatory actions. (Hunt, 1997; Yandle, 1986; Yandle, 1993) They serve an important regulatory role in response to acute increases in ventricular wall stress. A large number of cardiac conditions may cause an elevation of plasma levels of natriuretic peptides. Clinically, natriuretic peptides are of value in ruling out heart failure in patients presenting acutely to the emergency department with dyspnoea. (Maisel et al., 2002). Natriuretic peptides could also be useful in evaluating the severity and prognosis of patients with aortic stenosis (AS). Severe AS causes an increase in afterload and end-systolic left ventricular (LV) wall stress that, over time, leads to concentric myocardial hypertrophy. (Wachtell, 2008) This anatomical change of the LV is characterized at the molecular level by the re-expression of fetal isogenes, including increased gene expression of natriuretic peptides in the ventricular cardiomyocytes. (Sadoshima, 1992; Cameron, 1996) This chapter reviews the existing data on natriuretic peptide measurement in AS, to summarize how these biomarkers can be utilized in clinical practice, and to explore their therapeutic implication concerning the optimal timing of aortic valve replacement in the setting of severe AS.