P1553 Regional peak systolic longitudinal strain during dipyridamole stress echocardiography in patients with normokinetic response determined by visual assessment
Authors: Wierzbowska-Drabik K , Kasprzak J D , Sobczak M , Gaibazzi N , Picano E 
Published: January 2020

Abstract

OnBehalf
on behalf of the Stress Echo 2020 study group of the Italian Society of Echocardiography and Cardiovascular Imaging (SIECVI)

Background
Regional wall motion (RWMA) remains the cornerstone of stress echocardiography (SE) and its evaluation is still based on visual assessment by 2D. Regional longitudinal peak systolic strain (LPSS) provides a quantitative, operator-independent assessment of RWMA.

Aim
To compare 2D (qualitative) versus strain (quantitative) assessment of RWMA during dipyridamole SE.

Methods
In a prospective study we recruited 17 patients (mean age 69 ± 7 years, 11 women) with known or suspected CAD referred for accelerated high dose (0.84 mg/kg in 6") dipyridamole SE. We included patients with normokinesis at rest and with normal SE response. A 17-segment model was used to assess RWMA and strain (LPSS and global longitudinal strain, GLS). Ejection fraction (EF) was measured with Simpson"s biplane method. LPPS and GLS were measured using Automated Function Analysis (AFI).

Results
289 segments could be assessed head-to-head with the 2 methods (2D and Strain). Heart rate was 61 ± 8 bpm at rest and rose to 86 ± 19 at peak stress (p = 0.0001) EF increased from 66 ± 7% (rest) to 73 ± 5% (peak stress, p = 0.0006 vs rest). GLS increased from -17.9 ± 3.4% at rest to -19.8 ± 2.4% at peak stress (p = 0.0074). Stress-rest (Δ) changes in EF did not correlate with Δ-GLS (r = 0.2, p = ns). LPSS was -18.2 ± 5.2% at rest and on average increased to -19.7 ± 5.8 % (p &lt; 0.0001 vs rest), with heterogeneity of regional contractile reserve, highest in apical segments 13-17 (n = 85, LPSS rest= -20.3 ± 4.9 vs stress = - 22.5 ± 4.3, p = 0.0002), intermediate in mid-segments 7-12 (n = 102, LPSS rest= -18.5 ± 5.0 vs stress = -19.8 ± 5.6, p= 0.0166) and lowest in basal segments 1-6 (n = 102, LPSS rest= -16.1 ± 5.0 vs stress = - 17.3 ± 6.1, p= =0.0518= ns), see figure. At individual segment analysis, 50 segments (17.3%) showed an unmatched response, with normal visual response and LPSS reduction (stress ≤ rest at least 15%), observed especially in basal segments, see Table, unmatched 2D strain segments.

Conclusions
DSE allows a simultaneous qualitative and quantitative assessment of regional wall motion and global function by 2D and advanced strain-based indices. Strain-SE is feasible and may corroborate the results of trained naked eye interpretation with quantitative support, but degree of changes in regional strain is related to specific position of segment in basal, mid or apical part of left ventricle, with unmatched results between visual and strain not infrequent, especially in basal segments.
Unmached 2D strain segments Basal (1-6), n = 102 Mid (7-12), n = 102 Apical (13-17), n = 85 P value Basal vs Mid P value Mid vs Apical P value Basal vs Apical 24 (23.5%) 18 (17.6%) 8 (9.4%) ns ns =0.0185 Number and proportion of segments with LPSS worsening ≥15% in basal, mid and apical portion of left ventricle.
Abstract P1553 Figure. Changes of regional LPSS during DSE