Material and methods
This study was a comparative cross-sectional study conducted at a
tertiary care hospital in North India in which
120 subjects including 80 patients
with isolated severe MS (MVA ≤1.5 cm2) with pulmonary
hypertension between 18-40 years of age who were in sinus rhythm and 40
age matched healthy controls were enrolled from cardiology outpatient
department. Patients with moderate to severe mitral regurgitation or
other significant valve involvement and co-morbidities like
hypertension, diabetes mellitus, coronary artery disease, overt LV
systolic dysfunction were excluded. Philips EpiQ 7C echocardiography
system with 2.4 MHz transducer was used for recording echocardiographic
images. The study was carried out after prior approval from the
institutional ethical committee and written informed consent was
obtained from all the participants.
For all subjects, standard two-dimensional (2D), M-mode and Doppler
echocardiograms were obtained according to the American Society of
Echocardiography guidelines.11 Baseline measurements
included were LA dimension, LV internal dimension in diastole
(LVIDd) and in systole (LVIDs) and LV
ejection fraction (LVEF). MVA ≤1.5 cm2 (by planimetry)
was considered to define severe MS and MVA <1.0
cm2 defined very severe MS.13 Peak
diastolic gradient (PG) and mean diastolic gradient (MG) across the
mitral valve was calculated by continuous wave (CW) Doppler tracing.
Apical four chamber (A4C) and apical two chamber (A2C) views were
recorded in all the patients. Right ventricle systolic pressure (RVSP)
was measured from tricuspid regurgitation jet velocity by CW Doppler
after ruling out primary involvement of tricuspid and pulmonary
valve.14 Three consecutive cardiac cycles were
recorded and averaged.
Pulmonary hypertension (PH) was graded based on peak RVSP as mild 36-45
mm Hg, moderate 46-60 mm Hg and severe if >60 mm
Hg.15 Patients were classified according to the New
York Heart Association (NYHA) functional classification. Patients in
NYHA class IV were not included because all the patients recruited were
from OPD visits and were ambulatory.