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Short Length of Stay After Elective Transfemoral Transcatheter Aortic Valve Replacement Is Not Associated With Increased Early or Late Readmission Risk In acute HF and iron deficiency, IV ferric carboxymaltose reduced HF hospitalizations, but not CV death, at 1 y Left Ventricular Rapid Pacing Via the Valve Delivery Guidewire in Transcatheter Aortic Valve Implantation The multiple causes and treatments of heart failure: focus on genetic and molecular mechanisms and non-pharmacological interventions Relationship Between Hospital Surgical Aortic Valve Replacement Volume and Transcatheter Aortic Valve Replacement Outcomes Timing of intervention in asymptomatic patients with valvular heart disease Meta-Analysis of Comparison of 5-Year Outcomes of Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Patients With Unprotected Left Main Coronary Artery in the Era of Drug-eluting Stents Transcatheter and surgical aortic valve replacement in patients with bicuspid aortic valve

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.