Feature Tracking in Severe Aortic Regurgitation with Combined Aortic Stenosis: A Cardiovascular Magnetic Resonance Study

Background: Cardiovascular magnetic resonance feature tracking (CMR-FT) is increasingly used in clinical cardiology. It may be useful for detecting morphological alterations of cardiac function associated with aortic regurgitation (AR) combined with different degrees of aortic stenosis (AS) at an early time point before patients develop symptoms. Due to the often coexisting valvular stenosis, these patients do not display marked left ventricular dilation and generally present with preserved left ventricular ejection fraction in comparison to patients with pure AR. As a consequence, the optimal timing for surgery remains particularly unclear in asymptomatic patients with severe AR combined with AS.

Method: We retrospectively analyzed 26 asymptomatic patients (median age: 25 years; range: 9–65 years) with bicuspid aortic valve and severe AR (>40%) by CMR-FT. Left ventricular (LV) longitudinal strain (LS) was evaluated in the four chamber view, circumferential (CS) and radial (RS) strain in short axis slices. The patients were divided into 3 groups depending on the severity of AS associated; 8 patients had mild AS (velocity encoding [VENC] < 300 cm/s), 7 patients had moderate AS (300 ≤ VENC < 400 cm/s) and 11 patients had severe AS (VENC ≥ 400 cm/s). CMR-FT data of 22 healthy volunteers (median age: 21.5 years; range: 14–48 years) were used for comparison.

Results: RS and CS of the apical segments were significantly lower in patients with AR and mild AS component compared only to controls (median apical RS: 50% [range: 32–57%] vs. 61% [range: 41–106%], p < 0.0061 and median apical CS −25% [range: −19% to −26%] vs. −27% [range: −22% to −32%]; p = 0.0097, respectively). No other significant differences of global and regional RS, CS, and LS were present, neither between each of the three groups of combined valvular defect and healthy controls, nor comparing the aforementioned three patients groups to each other.

Conclusion: There was no difference in most of all parameters of CMR-FT between all the different groups. Only the apical RS and the apical CS of patients with severe AR and mild AS showed reduced values compared to healthy controls. These findings hardly support the use of CMR-FT in refining optimal timing of further treatment.

Publikationsverlauf

Artikel online veröffentlicht:
28. Januar 2023