Cardiovascular Journal of Africa: Vol 30 No 6 (November/December 2019)

23 / 66

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 30, No 6, November/December 2019 AFRICA 331
Fluorine-18 fluorodeoxyglucose positron emission
tomography in assessing myocardial viability in a
tertiary academic centre in Johannesburg, South Africa:
a pilot study
Dineo Mpanya, Nqoba Tsabedze, Carlos Libhaber, Brenda Kagodora, Mboyo-Di-Tamba Vangu
Abstract
Background: Positron emission tomography detects patients
with myocardial contractile dysfunction secondary to ischaemic
heart disease who may benefit from coronary revascularisation.
Methods: We reviewed technetium-99m sestamibi single-
photon emission computed tomography (SPECT) and fluo-
rine-18 fluorodeoxyglucose (F18-FDG) positron emission
tomography (PET) data from 236 patients imaged between
January 2009 and June 2015. The patients were grouped into
three groups: no evidence of viability, viability 1–10% and
viability > 10%.
Results: Viability exceeding 10% was evident in 55% of the
patients. On multivariate analysis, aspirin intake [OR: 1.92;
95% CI: 1.08–3.41; p = 0.026] and hypertension [OR: 1.89;
95% CI: 1.07–3.33; p = 0.029] were clinical factors associated
with the presence of myocardial viability.
Conclusion: Our study demonstrated that F18-FDG PET was
able to identify 55% of patients with ischaemic heart disease
with viability in more than 10% of the total myocardium
when using a 17-segment model.
Keywords: positron emission tomography, fluorine-18 fluorode-
oxyglucose, myocardial viability, hibernation
Submitted 13/10/18, accepted 8/5/19
Published online 12/6/19
Cardiovasc J Afr 2019; 30: 331–335
DOI: 10.5830/CVJA-2019-029
Positron emission tomography (PET) is a non-invasive molecular
imaging modality that may be used to distinguish myocardial
infarction frommyocardial hibernation in patients with ischaemic
heart disease. Regions of the myocardium with hibernating
cells demonstrate preserved fluorine-18 fluorodeoxyglucose
(F18-FDG) uptake while lack of F18-FDG uptake represents
infarcted tissue. 1,2 Much controversy surrounds the clinical utility
of PET in directing the management of stable coronary artery
disease complicated with cardiomyopathy.
Coronary revascularisation of hibernating myocytes is
associated with improved patient survival. 3,4 However, some
studies have failed to show a reduction in cardiac death,
myocardial infarction or recurrent hospitalisation for a cardiac
cause, when comparing PET-guided management versus
standard of care. 3,5-7 The clinical benefit of PET in guiding the
management of patients with ischaemic cardiomyopathy has
never been assessed in Johannesburg, South Africa. In this
preliminary work, we aimed to report on our experience with the
use of F18-FDG PET for the evaluation of myocardial viability
in patients with ischaemic heart disease.
Methods
We conducted a retrospective analysis of hospital medical records
for 240 consecutive patients referred for evaluation of myocardial
viability in the Department of Nuclear Medicine and Molecular
Imaging at the Charlotte Maxeke Johannesburg Academic
Hospital (CMJAH). The medical records reviewed were from
January 2009 to June 2015. We included all patients who were 18
years of age or older who had had a prior resting perfusion study
with technetium-99m sestamibi (Tc-99m sestamibi) gated single-
photon emission computed tomography (SPECT), subsequently
followed by cardiac imaging with F18-FDG PET.
A total of four patients did not meet the inclusion criteria.
One patient had viability imaging assessed with a different
radiopharmaceutical agent (thallium-201 chloride), another had a
resting perfusion study done outside the CMJAH referral network,
and two patients had missing perfusion scan results (Fig. 1).
All patients had ischaemic heart disease as documented by
a clinical history of myocardial infarction, resting and stress
electrocardiograms (ECG), echocardiography or angiography.
Clinical information was collected from in- and out-patient medical
records. The referral centres included the CMJAH, Chris Hani
Baragwanath Academic Hospital (CHBAH) and Helen Joseph
Hospital (HJH). These centres are all part of the clinical academic
complexes of the University of the Witwatersrand in Johannesburg,
South Africa. Ethical clearance was awarded by the University of
the Witwatersrand Human Research Ethics Committee.
Department of Nuclear Medicine and Molecular
Imaging, Faculty of Health Sciences, University of the
Witwatersrand, Charlotte Maxeke Johannesburg Academic
Hospital and Chris Hani Baragwanath Academic Hospital,
Johannesburg, South Africa
Dineo Mpanya, MB ChB,
Carlos Libhaber, PhD
Brenda Kagodora, MSc
Mboyo-Di-Tamba Vangu, PhD
Division of Cardiology, Department of Internal
Medicine, Faculty of Health Sciences, University of the
Witwatersrand, Charlotte Maxeke Johannesburg Academic
Hospital, Johannesburg, South Africa
Nqoba Tsabedze, MB BCh