CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 6, July 2012
324
AFRICA
for normally distributed variables, and median [inter-quartile
range (IQR)] for non-parametric variables. Comparison between
baseline and follow-up ECGs was done using paired
t
-tests
for normally distributed numerical variables, Mann-Whitney/
Wilcoxon signed rank tests for non-parametric paired numerical
variables, and chi-squared tests for categorical variables and
proportions. Multivariate analysis was conducted using linear
and logistic regression for numerical and categorical outcome
variables, respectively.
Results
Table 2 summarises the clinical and demographic profiles of the
78 women with
de novo
PPCM, 10 of whom experienced a first-
ever detected episode of mildly raised blood pressure at some
stage during the index pregnancy. The case report and Fig. 1
describe such a typical case.
Interestingly, no patients under the age of 17 years presented
to either study unit and 90% of patients included were young
women of African ancestry. Of the 10% that were of non-black
African ethnicity, almost all were of mixed ancestry, with
only one Caucasian patient. The majority of respondents
were normotensive and experienced onset of symptoms in the
postpartum period (median 18 days, IQR 6–30 days). However,
8% of respondents reported the onset of symptoms prepartum, of
which only two were hypertensive (one mild and the other with
moderate hypertension, defined as per standard protocol).
22-24
Table 3 summarises baseline ECG abnormalities/variations
from normal (
n
=
78). The majority of cases (90%) were in sinus
rhythm, although mean heart rate was markedly elevated, with
45% of cases in sinus tachycardia (defined as those
≥
100 beats/
min, given that our patients’ maximum heart rate was 134 beats/
min). Only three patients (4%) had completely normal ECGs;
excluding those with an elevated heart rate, this increased to nine
patients (12%). Overall, 49% (95% CI: 37–60) of cases had a
major Minnesota ECG abnormality detected, while 62% (95%CI:
51–74) had a minor ECG variant. A combined total of 63 (81%;
95% CI: 70–89%) cases had one or both forms of abnormality
detected on their 12-lead ECG. Of the major abnormalities,
major T-wave anomalies (38%), followed by abnormal QRS axis
(26%) were the most common (Fig. 2). T-wave anomalies were
also the most common of all documented ECG abnormalities
overall (59%), followed by atrial abnormalities (29%).
Univariate analysis showed no association between LV
systolic function and baseline ECG readings. However, on
adjustment for age, functional class, echocardiographic LV
dimensions, and all the other ECG parameters listed in Table
3, major T-wave abnormalities correlated negatively with left
ventricular systolic dysfunction. The presence of major T-wave
changes was associated with a clinically relevant 9% (95% CI:
1–16;
p
=
0.03%) reduction in LVEF compared to those without
T-wave changes.
At six months, a number of clinical parameters had improved
in surviving cases subjected to study follow up (
n
=
44) (Table 4).
Overall, 55% had no residual evidence of LV systolic dysfunction
(
p
<
0.001), although 10% still reported functional impairment
(NYHA class II or more). Overall, 25% of this sub-set of cases
had a normal 12-lead ECG at six months.
Case report: the ECG in PPCM
Our patient presented to hospital one week after giving birth through spontaneous vaginal delivery, reporting a five-
week history of shortness of breath equivalent to New York Heart Association functional class II, two-pillow orthopnoea
associated with cough, bilateral leg swelling, and mild dizziness. On further interrogation, there was a positive family
history of sudden ‘unexplained’ death of her grandmother. Our patient denied any consumption of alcohol or tobacco
products.
Clinical examination revealed central and peripheral signs of fluid overload. The pulse rate was 92 beats per minute,
this being weak, with occasional irregularities suggestive of ventricular extrasystoles. Her blood pressure was 97/72
mmHg, her apex beat displaced laterally, and the abdominal examination proved there to be tender hepatomegaly.
Positive findings on cardiac auscultation included a loud, split, second heart sound, and systolic murmur best heard over
the mitral and tricuspid areas. Chest auscultation revealed bilateral basal crepitations.
Chest X-ray demonstrated four-chamber cardiomegaly and pulmonary congestion, while her ECG abnormalities
included right-axis deviation, with poor R-wave progression and diffuse T-wave inversion (Fig. 1a). Echocardiography
showed dilated cardiac chambers, markedly reduced systolic ventricular function (EF 35%), moderate to severe functional
mitral regurgitation, trace tricuspid regurgitation, and a small clear pericardial effusion. Tissue Doppler imaging revealed
no further evidence of diastolic dysfunction.
Further tests permitted the exclusion of other common causes of dilated cardiomyopathy, as well as important
differential diagnoses. The working diagnosis remained that of peripartum cardiomyopathy.
The patient was started on carvedilol, enalapril, spirinolactone and furosemide. Given the high risk for thrombo-
embolic phenomena presented with the ejection fraction of 35% and below, she was started on warfarin. Despite being
seen several times in between, six weeks later she continued to manifest the subtle arrhythmia of moderate-frequency
ventricular extrasystoles, with suboptimal heart rate control; hence digoxin was introduced.
Following regular follow-up visits, after six months she reported that she was well, without any heart-failure symptoms.
Her blood pressure had normalised to 113/64 mmHg and heart rate to 58 beats/min, while the pulse rhythm remained
irregular as if with ventricular extrasystoles (now at low frequency). The mitral regurgitation murmur had diminished to
grade 1. On ECG, the axis had now normalised, and although there remained diffusely inverted T-waves, their depths
had improved, and this inversion normalised in limb lead I. The patient now qualified for left ventricular hypertrophy by
voltage criteria using this same lead I (Fig. 1b). Echocardiography showed persistent but improved LV dilatation, minimal
functional tricuspid and mitral regurgitation, with improvement of LV systolic function to an EF of 49%.
