Semiquantitative assessment of the relative apical sparing pattern of longitudinal strain for cardiac amyloidosis identification.

BACKGROUNDS: The relative apical sparing pattern (RASP) of left ventricular (LV) longitudinal strain (LS) is frequently associated with cardiac amyloidosis (CA). However, the visual assessment of RASP is inconsistent, and the quantitative assessment of RASP is time-consuming. This study aimed to compare assessments of RASP for the identification of CA with conventional assessments and investigate their reproducibility and relevance on the assessments. METHODS: Forty patients with biopsy-proven CA were compared with 80 hypertrophied patients matched for mean LV wall thickness. We compared the discriminative abilities of three assessments of RASP to identify CA (visual, quantitative, and semiquantitative). Nine patterns of semiquantitative RASP were investigated; finally, it was defined as "reduction of LS" (≥ -10%) in ≥5 (of 6) basal segments, relative to "preserved LS" (< -15%) in at least one apical segment. RESULTS: The concordance between the two observers for visual RASP was modest (κ = 0.65). On the other hand, the consistency for semiquantitative RASP was perfect (κ = 1.00). The discriminative ability of semiquantitative RASP (area under the curve [AUC]  = 0.74) was significantly better than that of visual RASP (AUC = 0.65) and equivalent to that of binary quantitative RASP. CONCLUSION: Semiquantitative RASP assessment is reproducible and accurately discriminates CA. This simple assessment may help readily refine the risk stratification of patients with diffuse LV hypertrophy.

Prognostic assessment of relative apical sparing pattern of longitudinal strain for severe aortic valve stenosis.

BACKGROUNDS: The relative apical sparing pattern (RASP) of left ventricular (LV) longitudinal strain (LS) is frequently associated with cardiac amyloidosis. Elderly patients with aortic valve stenosis (AS) complicated by transthyretin amyloid cardiomyopathy have poor prognosis. Furthermore, deteriorated basal LS in AS patients has been reported to be associated with adverse outcome. We investigated the association between RASP and outcomes in patients with severe AS. METHODS: We retrospectively studied 156 consecutive patients with severe AS and preserved LV ejection fraction. RASP was assessed by both of semi-quantitative (sRASP) and quantitative (qRASP) methods. sRASP was defined as a deterioration of LS (≥-10%) in ≥ 5 (of 6) basal segments, relative to preserved LS (<-15%) in at least 1 apical segment. qRASP was calculated using the following formula: average apical LS/(average basal LS + average mid-ventricle LS); qRASP ≥ 1 was defined as positive. Patients were followed up to determine outcomes, which included sudden cardiac death or unexpected admission due to heart failure, over a median of 1.9 years. RESULTS: sRASP and qRASP were assessed in all patients, but 24 and 42 patients fulfilled the criteria for sRASP and qRASP, respectively. Both assessments were significantly associated with outcomes (n = 44; 28%). Furthermore, sRASP was significantly associated with outcome after adjusting for EuroSCORE, NYHA ≥ II, or global longitudinal strain. A model based on these covariates for predicting outcomes significantly improved by adding sRASP. CONCLUSION: RASP is observed in some patients with severe AS and provides additive prognostic information over conventional parameters.