Faculty Opinions recommendation of Prognostic Implications of Blunted Feature-Tracking Global Longitudinal Strain During Vasodilator Cardiovascular Magnetic Resonance Stress Imaging.

Abstract Background Myocardial deformation analyses using cardiovascular magnetic resonance feature tracking (CMR-FT) have incremental value in the assessment of cardiac function beyond volumetric analyses. Since guidelines do not recommend specific imaging parameters, we aimed to define optimal spatial and temporal resolutions for CMR cine images to enable reliable post-processing. Methods Intra- and inter-observer reproducibility was assessed in 12 healthy volunteers. Cine images were acquired with differing temporal (20, 30, 40 and 50 frames/cardiac cycle) and spatial resolutions (high in-plane 1.5x1.5mm through-plane 5mm, standard 1.8x1.8x8mm and low 3.0x3.0x10mm). CMR-FT analyses comprised left ventricular (LV) global longitudinal strain (GLS) and systolic strain rate (SRs) as well as LV circumferential and radial strains (GCS and GRS) and right ventricular (RV) GLS. Intra- and inter-observer reproducibility was assessed in all subjects. Results Temporal but not spatial resolution did impact absolute strain and SR. Maximum absolute changes between lowest and highest temporal resolution were as follows: 2.3% LV GLS, 2.2% GCS, 7.2% GRS, 1.7% RV GLS and 0.32s-1 SRs. Changes of time-integrated (strain) values occurred predominantly comparing 20 and 30 frames/cardiac cycle including LV GLS, GCS and GRS (p = 0.034, p = 0.008 and p = 0.034) in highest spatial resolution settings. In contrast, time-derivatives values (SRs) changed significantly from lower temporal resolutions to 40 frames/cardiac cycle and beyond (20 to 30 p = 0.002; 30 to 40 p = 0.018; 40 to 50 frames/cardiac cycle p = 0.075) in highest spatial resolution settings. Strain reproducibility was not affected by either temporal or spatial resolution. SRs variability as assessed by coefficient of variation decreased with higher temporal resolutions. Conclusion Temporal but not spatial resolutions significantly affect strain and SR in CMR-FT deformation analyses. Clinical CMR-FT strain and SR analyses require minimum temporal resolutions of 30 and 40frames/cardiac cycle, respectively to ensure precise quantification of myocardial function.

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Cardiovascular magnetic resonance‐assessed fast global longitudinal strain parameters add diagnostic and prognostic insights in right ventricular volume and pressure loading disease conditions

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/s12968-021-00724-5 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Shuang Leng ◽

Ru-San Tan ◽

Jiajun Guo ◽

Ping Chai ◽

Gangcheng Zhang ◽

...

Keyword(s):

Cardiovascular Magnetic Resonance ◽

Magnetic Resonance ◽

Right Ventricular ◽

Exercise Capacity ◽

Longitudinal Strain ◽

Global Longitudinal Strain ◽

Cardiopulmonary Exercise Testing ◽

Healthy Controls ◽

Metabolic Equivalents ◽

Automated Method

Abstract Background Parameters of myocardial deformation may provide improved insights into right ventricular (RV) dysfunction. We quantified RV longitudinal myocardial function using a fast, semi-automated method and investigated its diagnostic and prognostic values in patients with repaired tetralogy of Fallot (rTOF) and pulmonary arterial hypertension (PAH), who respectively exemplify patients with RV volume and pressure overload conditions. Methods The study enrolled 150 patients (rTOF, n = 75; PAH, n = 75) and 75 healthy controls. RV parameters of interest were fast global longitudinal strain (GLS) and strain rates during systole (GLSRs), early diastole (GLSRe) and late diastole (GLSRa), obtained by tracking the distance from the medial and lateral tricuspid valve insertions to the RV epicardial apex on cine cardiovascular magnetic resonance (CMR). Results The RV fast GLS exhibited good agreement with strain values obtained by conventional feature tracking approach (bias − 4.9%, error limits (± 2·standard deviation) ± 4.3%) with fast GLS achieving greater reproducibility and requiring reduced analysis time. Mean RV fast GLS was reduced in PAH and rTOF groups compared to healthy controls (PAH < rTOF < healthy controls: 15.1 ± 4.9 < 19.3 ± 2.4 < 24.4 ± 3.0%, all P < 0.001 in pairwise comparisons). In rTOF patients, RV fast GLS was significantly associated with metabolic equivalents, peak oxygen consumption (PVO2) and percentage of predicted PVO2 achieved during cardiopulmonary exercise testing. Lower RV fast GLS was associated with subnormal exercise capacity in rTOF (area under the curve (AUC) = 0.822, sensitivity = 72%, specificity = 91%, cut-off = 19.3%). In PAH patients, reduced RV fast GLS was associated with RV decompensated hemodynamics (AUC = 0.717, sensitivity = 75%, specificity = 58%, cut-off = 14.6%) and higher risk of clinical worsening (AUC = 0.808, sensitivity = 79%, specificity = 70 %, cut-off = 16.0%). Conclusions Quantitative RV fast strain and strain rate parameters assessed from CMR identify abnormalities of RV function in rTOF and PAH and are predictive of exercise capacity, RV decompensation and clinical risks in these patients. Trial registry Clinicaltrials.gov: NCT03217240

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