CBS 2019
CBSMD教育中心
中 文

Scientific Library

Abstract

Recommended Article

The Future of Biomarker-Guided Therapy for Heart Failure After the Guiding Evidence-Based Therapy Using Biomarker Intensified Treatment in Heart Failure (GUIDE-IT) Study Vericiguat in Patients with Heart Failure and Reduced Ejection Fraction Unexpectedly Low Natriuretic Peptide Levels in Patients With Heart Failure Initial experience with percutaneous mitral valve repair in patients with cardiac amyloidosis Left Main Revascularization With PCI or CABG in Patients With Chronic Kidney Disease: EXCEL Trial Successful bailout stenting strategy against lethal coronary dissection involving left main bifurcation Edoxaban versus Vitamin K Antagonist for Atrial Fibrillation after TAVR Predictors of high residual gradient after transcatheter aortic valve replacement in bicuspid aortic valve stenosis

Original Research2017 Sep 12;70(11):1339-1348.

JOURNAL:J Am Coll Cardiol. Article Link

Hemodynamic Response to Nitroprusside in Patients With Low-Gradient Severe Aortic Stenosis and Preserved Ejection Fraction

Lloyd JW, Nishimura RA, Eleid MF et al. Keywords: aortic stenosis; catheterization; low gradient; nitroprusside; pathophysiology

ABSTRACT


BACKGROUND Low-gradient severe aortic stenosis (LGSAS) with preserved ejection fraction (EF) is incompletely understood. The influence of arterial afterload and diastolic dysfunction on the hemodynamic presentation of LGSAS remains unknown.


OBJECTIVES - The authors sought to determine the acute hemodynamic response to sodium nitroprusside in LGSAS with preserved EF.


METHODS - Symptomatic patients with LGSAS and preserved EF underwent cardiac catheterization with comparison of hemodynamic measurements before and after nitroprusside.


RESULTS - Forty-one subjects (25 with low flow [LF], stroke volume index [SVI] ≤35 ml/m2, 16 with normal flow [NF]) were included. At baseline, LF patients had lower total arterial compliance (0.36 ± 0.12 ml/m2/mm Hg vs. 0.48 ± 0.16 ml/m2/mm Hg; p = 0.01) and greater effective arterial elastance (2.77 ± 0.84 mm Hg · m2/ml vs. 1.89 ± 0.82 mm Hg · m2/ml; p = 0.002). In all patients, nitroprusside reduced elastance, left ventricular filling pressures, and pulmonary artery pressures and improved compliance (p < 0.05). Aortic valve area increased to ≥1.0 cm2 in 6 LF (24%) and 4 NF (25%) subjects. Change in SVI with nitroprusside varied inversely to baseline SVI and demonstrated improvement in LF only (3 ± 6 ml/m2; p = 0.02).


CONCLUSIONS - Nitroprusside reduces afterload and left ventricular filling pressures in patients with LGSAS and preserved EF, enabling reclassification to moderate stenosis in 25% of patients. An inverse relationship between baseline SVI and change in SVI with afterload reduction was observed, suggesting that heightened sensitivity to afterload is a significant contributor to LF-LGSAS pathophysiology. These data highlight the utility of afterload reduction in the diagnostic assessment of LGSAS.