Cardiovascular magnetic resonance evaluation of symptomatic severe aortic stenosis: association of circumferential myocardial strain and mortality

Abstract

BackgroundIt is unknown whether circumferential strain is associated with prognosis after treatment of aortic stenosis (AS). We aimed to characterise strain in severe AS, using myocardial tagging cardiovascular magnetic resonance (CMR), prior to and following Transcatheter Aortic Valve Implantation (TAVI) and Surgical Aortic Valve Replacement (SAVR), and determine whether abnormalities in strain were associated with outcome.MethodsCMR was performed pre- and 6 m post-intervention in 98 patients (52 TAVI, 46 SAVR; 77 ± 8 years) with severe AS. TAVI patients were older (80.9 ± 6.4 vs. 73.0 ± 7.0 years, p < 0.01) with a higher STS score (2.06 ± 0.6 vs. 6.03 ± 3.4, p < 0.001). Tagged cine images were acquired at the basal, mid and apical LV levels with a complementary spatial modulation of magnetization (CSPAMM) pulse sequence. Circumferential strain, strain rate and rotation were calculated using inTag© software.ResultsNo significant change in basal or mid LV circumferential strain, or of diastolic strain rate, was seen following either intervention. However, a significant and comparable decline in LV torsion and twist was observed (SAVR: torsion 14.08 ± 8.40 vs. 7.81 ± 4.51, p < 0.001, twist 16.17 ± 7.01 vs.12.45 ± 4.78, p < 0.01; TAVI: torsion 14.43 ± 4.66 vs. 11.20 ± 4.62, p < 0.001, twist 16.08 ± 5.36 vs. 12.36 ± 5.21, p < 0.001) which likely reflects an improvement towards normal physiology following relief of AS. Over a maximum 6.0y follow up, there were 23 (16%) deaths following valve intervention. On multivariable Cox analysis, baseline mid LV circumferential strain was significantly associated with all-cause mortality (hazard ratio, 1.03; 1.01–1.05; p = 0.009) independent of age, LV ejection fraction and STS mortality risk score. ROC analysis indicated a mid LV circumferential strain > −18.7% was associated with significantly reduced survival.ConclusionTAVI and SAVR procedures are associated with comparable declines in rotational LV mechanics at 6 m, with largely unchanged strain and strain rates. Pre-operative peak mid LV circumferential strain is associated with post-operative mortality.Electronic supplementary materialThe online version of this article (doi:10.1186/s12968-017-0329-7) contains supplementary material, which is available to authorized users.

Dissecting myocardial mechanics in patients with severe aortic stenosis: 2-dimensional vs 3-dimensional-speckle tracking echocardiography

“…Patients with severe AS and preserved LVEF in our cohort exhibited lower-than-normal GLS, a finding consistent with that found in several prior studies [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. In patients with severe AS, the increased afterload may lead to left ventricular hypertrophy, decreased coronary perfusion, subendocardial ischemia, and eventually myocardial fibrosis [3,4].…”

“…Therefore, 3-dimensional (3D) speckletracking echocardiography could provide a more precise representation of myocardial deformation [12]. New insights into LV remodeling and myocardial deformation could potentially improve our ability to identify patients with aortic stenosis who are at highest risk for adverse remodeling or early LV dysfunction [13][14][15][16][17][18]. However, few studies have comprehensively characterized myocardial deformation in patients with severe aortic stenosis by 3D speckle-tracking echocardiography [18,19].…”

Dissecting Myocardial Mechanics in Patients With Severe Aortic Stenosis: 2-Dimensional vs 3-Dimensional–Speckle Tracking Echocardiography

“…A recent study by Musa et al (27) showed that transcatheter aortic valve implantation and surgical aortic valve replacement procedures were associated with comparable declines in rotational LV mechanics.…”

Aortic valvular imaging with cardiovascular magnetic resonance: seeking for comprehensiveness

“…Recently, Al Musa et al 12 demonstrated that patients with severe AS had a significantly worsened longitudinal and circumferential strain values compared to controls, which also correlated with the postoperative functional recovery and clinical outcome. 71 Interestingly patients with severe AS and no or mild symptoms demonstrate a comparable reduction in circumferential and longitudinal strain to those with significant symptoms. 12 Current guidelines recommend valvular replacement mainly for patient with symptomatic severe valvular disease, or LV function impairment.…”

“…A more important role of CMR in the selection of patients for valve replacement would be helpful for recognizing those who would benefit from AVD correction, even in terms of clinical outcome and LV reverse remodelling. 10,71 However, in clinical practise, the use of CMR in pre-surgical planning is still marginal in many centers, a secondary choice compared to echocardiogram and CTA, generally limited to selected cases (young patients or those with renal failure).…”