CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 8, September 2012
AFRICA
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hypertension, determined by direct-needle transducer
measurements. There was no pre-operative swan ganz floated in
these two patients as none was available, and the pre-operative
TTE had grossly underestimated the pulmonary artery pressures.
The operative procedures performed are listed in Table 2.
Time on cardiopulmonary bypass was 20–205 minutes (mean
130)
and on aortic cross clamp 89–114 minutes (mean 103).
All patients were initially easily weaned off bypass, although
two later required intra-aortic balloon pump (IABP) post bypass
for haemodynamic instability. Mechanical valves were used for
heart valve replacement and comprised four St Judes, three ATS
and two On-X valves. Septal defects were closed primarily if
less than 1 cm in diameter or otherwise glutaraldehyde-treated
autologous pericardium was used. An 8-mm Gore-Tex graft was
used for the modified Blalock-Taussig shunt.
Seven patients (43.7%) required blood, with a mean of two
units of whole blood transfused. Two patients who received
aprotonin were almost bone dry and required no transfusion. All
patients were extubated within 12 hours, with the exception of
one patient who required ventilation for longer than 24 hours.
Anticoagulation with intravenous heparin and Coumadin was
started on postoperative day 2 if there was no evidence of
significant bleeding. Heparin was discontinued once the INR
was within the desired therapeutic range of 2.5 to 3.5.
Thirty-day operative mortality was 12.5% (2/16) and involved
the first index cases at both institutions to undergo open-
heart surgery. Both were females with chronic severe aortic
regurgitation from rheumatic heart disease. The first patient
had severe pericarditis with dense adhesions, and following
uneventful surgery developed sudden pulmonary hypertension
and systemic hypotension a few minutes after protamine sulphate
administration, which was unresponsive to standard therapeutic
measures. Heparin was re-administered and cardiopulmonary
bypass quickly reinstituted due to haemodynamic collapse.
After a period of rest with an empty, beating heart, the patient
was separated from the bypass with inotropes and IABP. She
developed coagulopathy and died of haemorrhage, as fresh
frozen plasma, platelets and cryoprecipitate were unavailable at
the blood bank.
The second patient, also after an uneventful surgery,
developed unexplained sudden hypotension while transferring
to the intensive care unit and required pressors and IABP for
stabilisation. She required prolonged ventilation and died four
days later from pneumonia-related sepsis due to unavailability
of potent broad-spectrum antibiotics, in addition to a delay in
obtaining microbiological laboratory results.
There was no re-operation for bleeding, cardiac tamponade
or valvular dysfunction. There was no stroke, renal failure,
deep sternal wound infection or any other major morbidity. At
follow up there was one anticoagulant-related morbidity one
year postoperatively in a valve patient on Coumadin, resulting
in a first-trimester abortion, and a late mortality two years
postoperatively in the same patient from anticoagulant-related
haemorrhage during another pregnancy.
Discussion
In the 50 years since the introduction of the heart–lung machine
to clinical practice by Gibbons in 1953, open-heart surgery has
matured as a speciality and become routine in all the developed
nations and most of the underdeveloped world. However,
sub-Saharan Africa which, according to the World Health
Organisation lags behind in most aspects of healthcare, has yet
to develop heart surgery programmes to any significant extent.
While infectious diseases and malnutrition presently remain
their leading public health concerns, cardiovascular diseases are
expected to gain more prominence in coming decades.
Although there is a paucity of data on heart diseases in
sub-Saharan Africa, the consensus of experts is that rheumatic
fever and the sequelae of rheumatic heart disease are the
commonest forms of heart disease in Africa, followed closely
by dilated cardiomyopathy.
1-3
Both of these diseases affect
mainly children and young adults from socio-economically
disadvantaged segments of the population living in unsanitary
conditions, which predisposes them to infectious diseases
such as Group A Streptococcal pharyngitis, compounded by
malnutrition as a consequence of poverty.
While the exact incidence of congenital heart disease in the
population is unknown, it is estimated to occur in one in 100
live births worldwide. Ischaemic heart disease, prevalent in the
industrialised world, is rare in sub-Saharan Africa and seen only
in the small segment of the population exposed to Western diet
and lifestyles.
Seventy per cent of the estimated 150 million population of
Nigeria live below the poverty line, with inadequate housing,
sanitation and basic health services; 45.1% of the population is
under 15 and 4.8% over 65 years of age, with a life expectancy
of 52 years for men and 52.2 years for women.
4
It is therefore
TABLE 1. PRE-OPERATIVE DIAGNOSISAND NYHA CLASS
Diagnosis
Number of patients
Acquired heart disease
Severe mitral regurgitation
7
Severe mitral stenosis
2
Severe aortic regurgitation
2
Penetrating heart wound
1
Congenital heart disease
Ventricular septal defect
2
Patent ductus arteriosus
2
Atrial septal defect
1
Tetralogy of Fallot
1
NYHA
Class I
1
Class II
7
Class III
3
Class IV
7
TABLE 2. OPERATIONS PERFORMED
Operations
No of patients
Acquired heart disease
Mitral valve replacement
7
Aortic valve replacement
2
Repair right ventricular laceration
1
Congenital heart disease
Closure ventricular septal defect
2
Ligation patent ductus arteriosus
2
Closure atrial septal defect
1
Modified Blalock-Tausig shunt
1
