Introduction: Cardiomyopaties like Cardiac Amyloidosis (CA), are an important cause of Heart Failure (HF). They can cause endocardial or transmural involvement. It is possible to characterize the kind of affectation thanks to different phenotypes identified by 2D speckle tracking echocardiography. Purpose: To study the pattern of myocardial involvement in patients (p) affected by CA and HF. Methods: Comparative study of 30 p with CA and HF, in NYHA class =II/IV, of which 16 had preseved left ventricle ejection fraction (pLVEF) and 14 had reduced LVEF (rLVEF), considering as cut point a LVEF>50%. There was a control group (CG) of 16 healthy subjects. Twist, radial strain (RS), circunferential strain (CS) and longitudinal strain (LS) were determined using 2D speckle-tracking echocardiography, along with mitral annulus plane systolic excursion (MAPSE) and basal-apex distance (B-A). The following indexes were calculated: Twist (apical rotation+basal rotation, °); Torsion (twist/B-A, °/cm); Torsion Index (TorI: twist/MAPSE, °/cm), and Deformation Index (DefI:twist/LS,°). The last indexes are dynamic parameters that allow for a more realistic assessment of LV torsion, since they include longitudinal shortening measures such as MAPSE and LS, describing in a more complete and physiological way the global LV systolic movement.
Results: There were differences of age between the three gropus, being older the p with rLVEF and younger the ones in the CG (63,7 ± 2,8; 68,2 ± 11,5; y 73,9 ± 12,9 years respectively). LS and CS were lower in rLVEF group when compared with pLVEF group, as well as in pLVEF group compared with the CG. The p with pLVEF showed increased values of the dynamic torsion parameters (DefI and TorI), indicating a compensatory increase of LV twist that disappears in p with rLVEF. Twist and Torsion are significantly lower only in the rLVEF group (see table).
Conclusions: In both CA groups, LS and CS deterioration indicates endocardial and transmural involvement. The loss of compensation given by the increased LV twist, reflected by DefI and TorI, marks the transition to the deterioration of LVEF.
*:p value <0,01 between CG and pLVEF group; **:p value <0,01 between pLVEF and rLVEF