Details

Autor(en) / Beteiligte

• Nakayama, Tomohito
• Asanuma, Toshihiko
• Masuda, Kasumi
• Kozuma, Ai
• Minami, Seina
• Takeda, Serina
• Nakatani, Satoshi

Titel

Abstract 11010: Heterogeneity of After load Sensitivity in the Regional Myocardial Strain

Ist Teil von

• Circulation (New York, N.Y.), 2018-11, Vol.138 (Suppl_1 Suppl 1), p.A11010-A11010

Ort / Verlag

by the American College of Cardiology Foundation and the American Heart Association, Inc

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Electronic Journals Library

Beschreibungen/Notizen

• BackgroundAfterload sensitivity of global strain is well recognized and it should be paid attention when assessing patients with hypertension or aortic stenosis. However, little is known about how afterload affects regional strains. We investigated how afterload influences regional strains and whether there is heterogeneity of afterload sensitivity in regional strains and sought the mechanism of the heterogeneity if it exists.MethodsAfterload was augmented by aortic banding (AoB) in 21 open-chest dogs. Mid-papillary short-axis images of the left ventricle (LV) were acquired by Aplio Artida (Canon) at baseline and during AoB (frame rate99 fps). Circumferential strains in 6 segments (anteroseptal, septal, inferior, posterior, lateral, and anterior) were analyzed, and the absolute value of the decrease in peak systolic strain by AoB (ΔεS) was calculated in each segment. To assess the effect of the compensatory preload recruitment during acute afterload augmentation, the endocardial lengths of the septum and free wall were measured at end-diastole, and the increasing rate by AoB was calculated.ResultsLV systolic pressure was significantly increased during AoB (97±15 vs. 162±13 mmHg, p < 0.01). ΔεS in the septal segment was significantly larger than those in the lateral and anterior segments (septal vs. lateral and anterior; 6.7±3.6 vs. 3.2±4.8 and 2.9±4.1%, p < 0.05, respectively) (Figure). The increasing rate of the septal endocardial length by AoB was significantly lower than that of the free wall endocardial length (12.9±9.6 vs. 22.6±8.1%, p < 0.01).ConclusionThe decrease in the septal strain during afterload augmentation was larger than that in the free wall strain, indicating that there is heterogeneity of afterload sensitivity. The lower compensatory preload recruitment of the septum compared to the free wall seems to be one of the causes of the heterogeneity.