Objectives
To evaluate the invasive hemodynamic characteristics of patients with low-gradient aortic stenosis (LGAS) to gain more insights into pathophysiology of the different subgroups.
Background
The diagnostic work-up of severe AS can be challenging, especially in status of low-gradients.
Methods
A total of 600 patients with symptomatic LGAS (mean transvalvular gradient <40mmHg and aortic valve area ≤1.0cm2)and full hemodynamic assessment by left and right heart catheterization between September 2009 and November 2017, were analyzed. Patients were divided into three groups due to flow status: normal-flow low-gradient (NFLG-AS; n=296; left ventricular ejection fraction (LVEF)≥50%, stroke volume index (SVI)>35ml/m2), paradoxical low-flow low-gradient (PLFLG-AS; n=153; LVEF≥50%, SVI≤35ml/m2), classical low-flow low-gradient (CLFLG-AS; n=151; LVEF<50%).
Results
Mean age was 81.0±6.6 years, 50.8% were female and mean EuroSCORE II was 6.7±5.6%. Levels of left ventricular global afterload (Zva), pulmonary and systemic vascular resistance (PVRI/SVRI) were the lowest, whereas those of cardiac output (CO), and left and right ventricular stroke work index (LVSWI/RVSWI) the highest in patients with NFLG-AS (p<0.001). PLFLG-AS patients had lower levels of CO, LVSWI/RVSWI as well as higher levels of Zva, valvular resistance, and PVRI/SVRI (p<0.001). CLFLG-AS was associated with increased pulmonary, right atrial and left ventricular end-diastolic pressures (p<0.001). These findings are summarized in Figure 1.
Conclusions
Patients with NFLG-AS represent the subgroup with the most regular hemodynamic status, whereas patients with CLFLG seem to be at the most progressed stage of the disease. Thereby, this assessment supports the suggestion of a stairway of progression of LGAS: from NFLG over PLFLG to CLFLG.https://www.abstractserver.com/dgk2019/jt/abstracts//P1569.htm