Cardiovascular Journal of Africa: Vol 28 No 4 (July/August 2017)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 4, July/August 2017 218 AFRICA
0.0001), and the majority were in NYHA functional class II or
III (71 vs 44%, p = 0.03) with a greater prevalence of moderate
MR, accompanied by a greater degree of impairment of early
relaxation in diastole (Table 4). Normotensive MR patients
had a greater prevalence of dilatation of the left ventricle and
severe MR with larger left atrial volume (Table 4). There were
no significant differences with regard to the morphology of the
mitral valve apparatus or Carpentier classification of leaflet
dysfunction between the two groups ( p > 0.05).
A greater proportion of patients with HIV had severe
MR compared to HIV-negative patients (50 vs 23%, p =
0.015). However no significant differences were observed in the
echocardiographic parameters relating to dilatation of the LV,
LVEF, LV diastolic function or LA volumes (p > 0.05). Similarly
no significant differences were noted in any morphological
parameters or Wilkins score between the two groups (8.4 ±
1.2 vs 8.0 ± 0.9, p = 0.14). All HIV-positive patients had type
IIIa (restrictive) leaflet dysfunction, compared to HIV-negative
individuals, of whom 15% had mixed lesions (p = 0.05).
Concomitant organic morphological TV disease was more
common in HIV-positive than in HIV-negative patients (50 vs 21%,
p = 0.02). A similar degree of TR (p > 0.05) was present in both
groups. There was no difference in the pulmonary artery systolic
pressure between the HIV-positive and HIV-negative groups (37.2
± 15.4 vs 35.2 ± 18.7 mmHg, p = 0.64). The degree of RV dilatation
(33.5 ± 9.0 vs 31.4 ± 5.8 mm, p = 0.22) and RV function (11.9 ±
2.9 vs 13.4 ± 13.2 cm/s, p = 0.61) were not statistically different
between the HIV-positive and -negative groups.
Discussion
The pertinent findings in this contemporary cohort of patients
with moderate or severe rheumatic MR include: (1) a significant
increase in the mean age of the patients compared to previous
studies; (2) infrequent occurrence of ARF; (3) a high incidence
of co-morbid disease, including hypertension and HIV; and (4)
advanced morphological changes in the mitral valve, including
leaflets and subvalvular apparatus on echocardiography.
These findings are inmarked contrast to the detailed evaluation
published by Marcus et al. from the same hospital but almost
three decades earlier.6 In that study, from the total cohort of 737
patients, 219 had pure MR, 275 pure mitral stenosis and 220
mixed lesions. Furthermore, in the Marcus study, patients with
pure MR had thin leaflets, elongated chordae, a dilated annulus
and anterior leaflet prolapse; findings that were corroborated at
the time of surgery. 6 Pure MR was largely a function of active
rheumatic carditis and age; most were younger than 20 years
with clinical carditis documented in 14% and surgical features of
acute rheumatic carditis in 47% of the entire MR cohort.6
In contradistinction, we found only one patient with
active carditis. The mean age of our cohort was 44 ± 15.3
years and echocardiography revealed no leaflet prolapse, and
instead, marked leaflet thickening, calcification and retraction,
accompanied not infrequently by abnormality of the chordal
structures.
These features are compatible with the proposal that Marcus
and ourselves have advanced, where fulminant carditis is thought
to lead on to pure severe MR, and milder or recurrent carditis to
progress to pure mitral stenosis or mixed mitral valve disease.1,4,6
Rheumatic MR of patients in the current era results in the
predominance of Carpentier type IIIa leaflet dysfunction with
Wilkins scores that are similar to patients with MS. We postulate
that less fusion of the commissures, a predominance of posterior
leaflet thickening and immobility, accompanied by subvalvular
abnormality, predispose patients to develop predominantly
Table 2. Comparison of the study by Marcus et al.6 with the current
cohort of patients with isolated rheumatic mitral regurgitation
Variables
Marcus et al.6
(n = 219)
Meel et al.
(n = 84) p-value
Clinical
Age (years) 19 ± 11 44 ± 15.3 < 0.001
Females (%) Not specified 84
Race Black Africans Black Africans
NYHA functional class (%) III (100) III (24) 0.001
Acute rheumatic fever (%) 14 1.2 < 0.001
Co-morbidities (%) 0 78 < 0.001
Mitral valve morphology (%)
Dilated annulus 95 84.5 0.001
Leaflet thickness and pliability
Thin, pliable 95 5 < 0.001
Thickened, non-pliable 59 41 0.0049
Leaflet prolapse 84 20 < 0.001
Leaflet calcification (rigid) 5 27 < 0.001
Elongated chordae 92 0 < 0.001
Ruptured chordae 25 0 < 0.001
Commissural fusion 0 30 < 0.001
NYHA: New York Heart Association.
Table 3. Clinical and echocardiographic characteristics according to age
Variables
Age < 30 years
(n = 22)
Age > 30 years
(n = 62) p-value
Clinical
Systolic blood pressure 121.9 ± 11.2 124.9 ± 11.3 0.29
Diastolic blood pressure 77.8 ± 6.83 76.6 ± 9.6 0.60
Body mass index (kg/m2) 23.84 ± 4.78 28.2± 6.23 0.19
Body surface area (m 2) 1.62 ± 0.16 1.72 ± 0.18 0.04
NYHA functional class (I/II and III) 14/8 21/41 0.01
Gender (F/M) (%) 18/4 (81/19) 53/9 (85/15) 0.68
Echocardiographic
Moderate mitral regurgitation (%) 13 (59) 46 (74)
Severe mitral regurgitation (%) 9 (41) 16 (26) 0.18
LV end-diastolic diameter (mm) 53.7 ± 9.06 55.7 ±9.7 < 0.0001
LV end-systolic diameter (mm) 38.7 ± 9.31 42.3 ± 10.5 0.15
Interventricular septum
diameter (mm)
9.8 ± 5.9 8.6 ± 2.3 0.21
Posterior wall diameter (mm) 7.9 ± 1.1 8.9 ± 1.6 0.01
LV EDV indexed (ml/m 2)† 90.8 ± 22.9 94.8 ± 33.9 0.61
LV ESV indexed (ml/m 2)† 35.5 ± 16.9 42.4 ± 24.7 0.23
LV mass indexed (g/m2 )† 102.2 ± 44.2 105.7 ± 38.5 0.72
Relative wall thickness 0.30 ± 0.1 0.33 ± 0.1 0.24
LV ejection fraction (%) 61.4 ± 12.7 57.1 ± 12.7 0.26
Ejection fraction ≥ 60% 18 30
Ejection fraction < 60% 4 32 0.006
Average E′ (cm/s) 11.4 ± 3.3 7.6 ± 2.3 < 0.01
E/E′ lateral (cm/s) 13.2 ± 8.2 17.2 ± 9.3 0.04
E/A ratio 1.7 ± 0.34 1.4 ± 0.7 0.05
S′ lateral (cm/s) 8.9 ± 3.3 6.63 ± 1.7 < 0.0001
Left atrial volume indexed (ml/m 2 )† * 45 (37.1–148.5) 53 (41.2–74.5) 0.53
Data are presented as mean ± SD. LV: left ventricle, NYHA: New York Heart
Association; EDV: end-diastolic volume; ESV: end-systolic volume.
*Median (interquartile range) or percentage. † Values are indexed to body surface
area.