Clin Res Cardiol (2022). https://doi.org/10.1007/s00392-022-02002-5

Elevated wasted and decreased constructive work in non-obstructive hypertrophic cardiomyopathy: Results of the prospective Hypercard Registry
A. Batzner1, P. Hahn1, F. Sahiti1, C. Maack1, B. Gerull1, S. Frantz2, S. Störk1, H. Seggewiß1, C. Morbach1
1Deutsches Zentrum für Herzinsuffizienz, Universitätsklinikum Würzburg, Würzburg; 2Medizinische Klinik und Poliklinik I, Universitätsklinikum Würzburg, Würzburg;

Introduction: Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiac disease of the adult. Measurement of myocardial work (MyW) using pressure strain loops and systolic blood pressure was recently introduced as an innovative approach to non-invasively estimate myocardial performance: constructive work (CW) that contributes to cardiac output can be differentiated from wasted work (WW), which does not.

We compared global CW and WW in non-obstructive HCM and volunteers without cardiac disease. Since the performance of the septum might be a major contributor to potential obstruction in HCM, we also analyzed the performance of the basal septum in comparison to the basal lateral wall as remote region. 

 

Methods and Results: We analyzed 21 patients (6 women, mean age 56.7±15.3 years) with non-obstructive HCM, i.e. maximal intracavitary left ventricular gradient <30 mmHg (mean 10.2±5.4 mmHg). Out of those, 10 had been treated with alcohol septal ablation (3 women, 56.6±16.3 years) and 11 presented with genuine non-obstructive HCM (3 women, 56.7±15.1 years). Findings were compared with 18 apparently healthy volunteers of comparable age (11 women, mean age 58.3±12.1 years). Based on echocardiography-derived longitudinal systolic strain and cuff-measured peripheral systolic blood pressure (BP) as correlate of left ventricular systolic pressure (LVSP) we determined segmental and global CW and WW. Groups were compare using T-test or Mann-Whitney-U-test, as appropriate.

Global CW was 1611±447 mmHg% in non-obstructive HCM patients irrespective of prior treatment with alcohol septal ablation (p=n.s.). However global CW was much lower (-38%) compared to volunteers: 2608±387 mmHg% in (p<0.001). Global WW in non-obstructive HCM was 177±91 mmHg% (again irrespective of prior treatment), i.e. increased by 218% compared to volunteers (81±44 mmHg%; p<0.001).

Regarding segmental CW of the septal-basal segment, we also found 33% lower values in non-obstructive HCM patients (regardless of prior treatment) when compared to volunteers (989±350 mmHg% vs 1469±349 mmHg%; p<0.001), whereas WW in this segment did not show differences (178±203 mmHg% in non-obstructive HCM vs. 190±111 mmHg%; n.s.). By contrast, in the lateral-basal segment, differences between non-obstructive HCM and volunteers were less exaggerated for CW (-15%; 2049±802 mmHg% vs. 2423±589 mmHg%; n.s.), and a trend was observed for higher WW (+26%; 286±338 mmHg% and 106±117 mmHg%; p=0.065).

 

Summary: Compared to healthy volunteers, non-obstructive HCM patients showed lower global CW but higher global WW, implying impaired myocardial performance in HCM patients. On a segmental level, we found the same pattern of MyW impairment in the basal septum but less pronounced in the basal lateral wall. Our results imply MyW a novel method to sensitively assess impairment in myocardial performance in HCM patients. Further studies are necessary for validation of this potential promising method in obstructive HCM. 


https://dgk.org/kongress_programme/jt2022/aP1897.html