Hypercontractile phenotype of the left ventricle in patients with heart failure with preserved ejection fraction: too strong to be normal?

Hypercontractile phenotype (HP) of the left ventricle (LV) is an actionable therapeutic target in patients with chronic coronary syndromes (CCS), but its prevalence and meaning in patients with heart failure and preserved ejection fraction (HFpEF) remains unclear.

To assess the myocardial work correlates of the HP in patients with HFpEF.

In a prospective, observational, single-center, cross-sectional study, we recruited 62 healthy controls (55 ± 7 yrs, 36 males, 58.1%) and 129 patients (58 ± 8 yrs, 70 males, 54.3%) with HFpEF referred for resting transthoracic echocardiography with volumetric echocardiography and assessment of global work efficiency (GWE). We measured systolic blood pressure (SBP) with a cuff sphygmomanometer. We assessed quantitatively LV end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), force (SBP/ESV), stroke volume (SV), arterial elastance (SBP/SV), ventricular-arterial coupling (VAC, as SV/ESV), and cardiac output (CO= SV*heart rate).HP was identified a priori as value >7.87 mmHg/ml, corresponding to a value exceeding > 2SD (95% of values) of the distribution in normals. GWE was assessed with a single vendor together with global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and GWE.

LVEF and GLS values were similar in normal and HFpEF (EF: 63.3±4.7% vs 67.2±6.3%, p > 0.05; GLS: 21.4±1.4% vs 19.1±2.7%, p > 0.05). However, at individual patient analysis, 42 patients of the HFpEF group showed HP (32.6%). Compared to controls and patients with HFpEF without HP, HP patients showed higher values of heart rate and EF but lower values of SV, LVESV, LVEDV, similar values of GLS, and markedly higher values of GWI, GCW, and GWW with lower GWE. Multivariable linear regression analysis showed that force was independently associated with GWE (β=-0.356, P=0.002) and LVEF (β=0.219, P<0.0001), NTproBNP was independently associated with GWW (β=0.589, P=0.020) and GWE (β=-31.120, P<0.0001).

A HP of the LV with high force is frequent in HFpEF and is associated with a small heart, reduced SV, and lower mechanical efficiency with higher global work but a disproportionate increase in wasted work. Work analysis is more effective than GLS in identifying HFpEF with HP.