Relation between hypertension and systolic and diastolic left
ventricular function including segmental strain and strain rate
Background Left ventricular (LV) systolic and diastolic functions are
important cardiovascular risk predictors in patients with hypertension.
However, data on segmental, layer-specific strain, and diastolic strain
rates in these patients are limited. The aim of this study was to
investigate segmental two-dimensional strain rate imaging (SRI)-derived
parameters to characterize LV systolic and diastolic function in
hypertensive individuals compared with that in normotensive individuals.
Methods The study sample comprised 1194 participants from population
studies in Arkhangelsk and Novosibirsk, Russia, and 1013 individuals
from the Seventh Tromsø Study in Norway. The study population was
divided into four subgroups: A. healthy individuals with normal blood
pressure (BP), B. individuals on antihypertensive medication with normal
BP, C. individuals with systolic BP 140–159 mmHg and/or diastolic BP
>90 mm HG, and D. individuals with systolic BP ≥160 mmHg.
In addition to conventional echocardiographic parameters, global and
segmental layer-specific strains and strain rates in early diastole and
atrial contraction (SR E, SR A) were extracted. The strain and SR (S/SR)
analysis included only segments without strain curve artifacts. Results
With increasing BP, the systolic and diastolic global and segmental S/SR
gradually decreased. SR E, a marker of impaired relaxation, showed the
most distinctive differences between the groups. In normotensive
controls and the three hypertension groups, all segmental parameters
displayed apico-basal gradients, with the lowest S/SR in the basal
septal and highest in apical segments. Only SR A did not differ between
the segmental groups but increased gradually with increasing BP.
End-systolic strain showed incremental epi-towards endocardial
gradients, irrespective of the study group. Conclusion Arterial
hypertension reduces global and segmental systolic and diastolic left
ventricular S/SR parameters. Impaired relaxation determined by SR E is
the dominant factor of diastolic dysfunction, whereas end-diastolic
compliance (by SR A) does not seem to be influenced by different degrees
of hypertension. Segmental strain, SR E and SR A provide new insights
into the LV cardiomechanics in hypertensive hearts.