Longitudinal Assessment of Left Atrial Remodeling in Patients With Chronic Severe Aortic Regurgitation.

BACKGROUND: There are significant sex and age differences in left ventricular (LV) remodeling that may lead to disparity in outcomes when used to inform the timing of aortic regurgitation (AR) intervention. OBJECTIVES: The aim of this study was to examine whether left atrial (LA) parameters might represent better criteria than LV parameters to inform the timing of AR intervention. METHODS: Using data on patients with moderate to severe or severe AR with serial echocardiography (2010-2016), the longitudinal trends in left atrial volume index (LAVI) and left atrial reservoir strain (LAr) were evaluated by sex and age. The incremental utility of these parameters in predicting adverse events over LV parameters was also determined. RESULTS: In 525 patients (25.7% women) with 1,687 echocardiograms over a median follow-up period of 2.0 years (Q1-Q3: 1.0-3.6 years), there was significant increase in LAVI (1.0 mL/m2 per year [95% CI: 0.76-1.2 mL/m2 per year]) and decrease in LAr (-1.3% per year [95% CI: -1.6% to -0.92%]), without a significant interaction by sex or age category (P for interaction ≥ 0.17). In addition, both LAVI and LAr were significant predictors of adverse events independent of LV parameters. The optimal discriminatory thresholds were 37 mL/m2 for LAVI and 35% for LAr. These thresholds were similar across categories of sex and age. Within the relatively short-term follow-up, surgery was associated with survival benefit among patients with LAVI ≥37 mL/m2 (HR: 0.33 [95% CI: 0.15-0.72]; P = 0.006) but was not statistically significant among patients with LAVI <37 mL/m2 (HR: 0.46 [95% CI: 0.18-1.17]; P = 0.09). Similarly, surgery was associated with survival for the subgroup with LAr ≤35% but not among those with LAr >35%. CONCLUSIONS: Unlike LV remodeling, LA remodeling demonstrates a similar rate of progression between categories of sex and age among patients with AR. In addition, LA parameters provide incremental prognostic value over LV parameters.

Carotid Duplex Ultrasonography to Assess Severity of Low-Flow Low-Gradient Aortic Stenosis.

BACKGROUND: Patients with low-flow, low-gradient aortic valve stenosis constitute a substantial subset of all severe aortic stenosis patients. However, assessment of true severity of these patients can be challenging. In this analysis, we study the utility of the common carotid artery waveforms to distinguish true from pseudo-severe low-flow low-gradient aortic stenosis. METHODS: This is an observational analysis that included patients who underwent a transthoracic echocardiogram (TTE) and duplex carotid ultrasonography (DCUS) and had low-flow, low-gradient aortic stenosis with reduced left ventricular ejection fraction (LVEF) on the index TTE (LVEF <50%, calculated aortic valve area [AVA] of ≤1.0 cm2, mean and peak gradient of <40 and <64 mm Hg, respectively, and stroke volume index <35 mL/m2). Patients were classified as pseudo-severe and true-severe aortic stenosis based on additional subsequent testing. Differences in various TTE and DCUS waveform parameters across the aortic valve and the common carotid artery were compared between the 2 groups. RESULTS: The study included 30 patients (60 carotid arteries). Fifteen patients were categorized as pseudo-severe and 15 as true severe aortic stenosis. There were no significant differences in calculated AVA, LVEF, stroke volume/stroke volume index, and Doppler Velocity Index in the 2 groups. Mean and peak gradient were higher in patients with true-severe aortic stenosis. Carotid acceleration time (cAT) was significantly prolonged in patients with true-severe compared with pseudo-severe aortic stenosis. A cAT ≥80 ms was 83.3% sensitive and 83.3% specific for true-severe aortic stenosis. CONCLUSION: cAT acceleration time may be used to distinguish true from pseudo-severe low-flow, low-gradient aortic valve stenosis.