Methods
We enrolled patients affected by CHF who were referred to the Heart
Failure Outpatients Clinic of the Cardiology Unit of the Polyclinic
University Hospital Riuniti of Foggia, Italy, between October 2020 and
January 2023. All the patients were enrolled in the Daunia registry,
which was approved by the Institutional Ethics Committee of the
Polyclinic University Hospital of Foggia, Italy (Protocol Code 68/CE/20,
approved on 26 May 2020), and all provided written informed consent to
participate.
The following inclusion criteria were considered: history of heart
failure of any origin with recommended medical therapy at the time of
the enrolment and in clinically stable condition for at least 30 days
(e.g. no significant changes in hemodynamic status or medical therapy).
Patients diagnosed with atrial fibrillation were enrolled if a regular
ventricular paced rhythm was present, whereas they were excluded if an
irregular rhythm was observed.
At the time of enrolment, each participant underwent a medical
evaluation, including an electrocardiogram (ECG) and two-dimensional
echocardiography.
Medical examination and electrocardiogram. Each participant’s
full medical history was collected. A physical examination and a 12-lead
ECG were performed. Any evidence of ischemic cardiomyopathy, arterial
hypertension, atrial fibrillation, diabetes mellitus, and/or
dyslipidaemia was documented together with any history of chronic kidney
disease and dialysis. New York Heart Association (NYHA) classes,
anthropometric data, systolic and diastolic arterial pressures, and
heart rhythms were also recorded. If available, the most recent routine
blood chemistries were also documented. In particular, by serum
creatinine, the glomerular filtration rate was calculated using the
abbreviated CKD-EPI formula (GFR-EPI, ml/min/1.73 m2)
[8].
Echocardiographic evaluation. Two-dimensional echocardiographic
imaging and Doppler acquisition were performed using an EPIQ CVx system
(Philips, Amsterdam, the Netherlands) with an S5-1 transducer. At the
baseline, five cycles of ECG-guided standard parasternal long- and
short-axis, apical two-, three-, and four-chamber, and subcostal views
were acquired. The LV end-diastolic diameter (LVEDD) and
interventricular septum and LV posterior wall thicknesses were measured;
the LV mass indexed for body surface area was calculated based on
current recommendations [9]. Additionally, to analyse the tricuspid
annular plane systolic excursion, an RV-focused four-chamber view was
obtained. The LV end-diastolic volume (LVEDV), LV end-systolic volume
(LVESV), and LV ejection fraction (LVEF) were calculated using Simpson’s
rule. The LA volume was also calculated using Simpson’s rule and indexed
for body surface area (LAVI). Using colour Doppler, mitral (MR) and
tricuspid (TR) regurgitation were evaluated semi-quantitatively and
assigned arbitrary units ranging from 0 to 4. The maximum
trans-tricuspid valve pressure gradient was assessed using
continuous-wave Doppler. Pulmonary systolic arterial pressure (PASP) was
estimated based on the vena cava diameter. Peaks of early wave velocity
at the mitral valve (E) were measured using pulsed Doppler. Furthermore,
the early diastolic velocity peaks (e’) at the level of the septal (e’s)
and lateral (e’l) mitral annulus were measured using pulsed and tissue
Doppler imaging (TDI) [9]. Then the means of e’s and e’l (e’m) as
well as the ratios between E and e’s (Ee’s) and E and e’m (Ee’m) were
calculated.
The AutoStrain application of the Philips EPIQ CVx ultrasound systems
was used for the ‘off-cart’ analysis of strain from stored examinations.
Values for LV global longitudinal strain (LV-GLS) were obtained from the
analysis of two-, three-, and four-chamber views. The software
automatically generated curves representing longitudinal strain; LV-GLS
was calculated by averaging values obtained in all the segments. In this
study, reduced systolic strain is indicated by values that are less
negative than those determined at the baseline. The global longitudinal
strain of the right ventricle (RVGLS) and that of the free wall (RVfwLS)
were also calculated automatically from the values obtained in an
RV-focused four-chamber view. In this study, reduced ventricular
systolic strain is indicated by values that are less negative than those
determined at the baseline.
By the standard four-chamber view, the AutoStrain application of the
Philips EPIQ CVx ultrasound systems was also used for the ‘off-cart’
analysis of LA strain from stored examinations. As shown in Figure 1,
the LA strain of reservoir (LAr), including those ofconduit (LAcd) and contraction (LAct), were calculated
(D.D., E.T.). Finally, the ratios between LAr and E/e’s (LAr/Ees) and
LAr and E/e’l (LAR/Eel) and that between LAr and E/e’m (LAr/Eem) were
evaluated [7].