Impact of systolic coronary flow reversal in patients with aortic stenosis: assessment with transthoracic echocardiography

Abstract Background In patients with aortic stenosis (AS), increased systolic wall stress due to increased afterload reduces systolic coronary flow, often leading to systolic coronary flow reversal (SFR) in epicardial coronary arteries. Purpose We used transthoracic echocardiography (TTE) to evaluate severity of AS, left ventricular function, and coronary flow, and investigated echocardiographic indicators associated with SFR. Methods We prospectively evaluated consecutively presenting patients who visited our valvular heart disease outpatient clinic or were admitted to our hospital for investigation of AS (July 2023 to February 2024). Based on ESC guidelines, severity of AS and the left ventricular function were assessed with TTE. At the same time, TTE was used to measure distal left anterior descending coronary artery flow. SFR was defined as the presence of a reversal coronary flow component in systole. Based on the presence or absence of SFR in coronary flow measurements, patients were classified into SFR+ or SFR− groups. The inclusion criteria were AS of moderate or greater severity, and the exclusion criteria were known coronary stenosis and the inability to assess coronary flow. Results Enrolled 28 patients were classified into SFR+ (7 patients) and SFR − (21 patients) groups. Comparing baseline characteristics between the SFR+ and SFR− groups, although there were no significant differences in left ventricular indicators such as left ventricular mass index, left ventricular ejection fraction, stroke volume index, and E/e’ between the two groups, left ventricular global longitudinal strain was significantly lower in the SFR+ group (12.0±3.1%, 14.9±3.0%, p=0.026) (Table 1). Regarding indexes of AS assessment, aortic valve peak velocity and aortic valve mean pressure gradient values were significantly higher in the SFR+ group than in the SFR − group ([475±68 cm/s, 379±55 cm/s, p<0.001] and [56.2±16.5 mm Hg, 34.8±10.5 mm Hg, p<0.001], respectively) (Table 1). Representative cases show Figure 1. Conclusion The presence of SFR in patients with AS assessed using TTE may be a simple echocardiographic index that may be associated with potential decline in left ventricular function and progression of AS.