The complex principle of cause and effect
Michael J. Zellweger, MD
University Hospital, Basel, Switzerland
Received Apr 4, 2016; accepted Apr 4, 2016
See related article, pp. 1305–1311
The association between diabetes and congestive
heart failure and its inﬂuence on prognosis are widely
known and have been extensively documented.
Patients with diabetes have more extensive coronary
artery disease, lower left ventricular ejection fraction,
and congestive heart failure than non-diabetic patients.
Rubler et al ﬁrst described ‘‘diabetic cardiomy-
opathy’’ in 1972 based on four adult diabetic patients
with congestive heart failure that could not be explained
by coronary artery disease, hypertension, valvular heart
disease, or alcoholism. Subsequently, the term ‘‘diabetic
cardiomyopathy’’ as a diastolic and/or systolic heart
failure in diabetic patients in the absence of signiﬁcant
concomitant coronary artery disease or arterial hyper-
tension has been deﬁned.
Ehl et al documented that diabetes was an inde-
pendent predictor of a decreased left ventricular systolic
function in 2635 patients who underwent myocardial
perfusion SPECT. Diabetes was an independent pre-
dictor of a decreased ejection fraction besides male sex,
presence of typical angina, pharmacologic stress, the
summed rest and summed difference score, and thus
independent of the presence and extent of coronary
On the other hand, our group recently has published
data on 400 asymptomatic patients with type 2 diabetes
(BARDOT trial). In BARDOT, patients with an abnor-
mal myocardial perfusion SPECT had a signiﬁcantly
lower left ventricular ejection fraction than patients with
a normal scan.
Van den Hoogen et al evaluated 525 asymptomatic
diabetic patients using the ‘‘anatomic approach’’ (coro-
nary artery calcium and coronary computed tomography
angiography). Patients with a normal coronary computed
tomography scan had an excellent prognosis (not taking
into account any perfusion data). Both the calcium score
and the coronary angiography data effectively risk strat-
iﬁed diabetic patients without chest pain.
Von Scholten et al evaluated the functional and struc-
tural aspects of atherosclerosis in asymptomatic patients
with type 2 diabetes.
These patients who were free of overt
cardiovascular disease had a high prevalence of coronary
microvascular dysfunction, especially with concomitant
albuminuria, suggesting a common microvascular impair-
ment occurring in multiple microvascular beds.
calcium score was added to the analysis, there was also a
trend (P = .032) toward an inverse association with reduced
coronary ﬂow reserve (CFR).
In the current issue of the Journal, Jua
rez-Orozco et al
aimed to evaluate the relationship of diabetes and left
ventricular ejection fraction when quantitative perfusion
was taken into account. Their conclusion was that diabetes
signiﬁcantly inﬂuenced PET-measured systolic function
in patients without prior myocardial infarction, indepen-
dently of myocardial perfusion parameters. Gender, age,
hypercholesterolemia, hypertension, smoking, diabetes,
stress myocardial blood ﬂow, and myocardial perfusion
reserve were incorporated into the multivariate analysis.
Of note, neither information regarding anti-diabetic
therapy, effectiveness of the therapy (e.g., HbA1c),
microalbuminuria, other end-organ damage nor infor-
mation regarding lipid lowering therapy was reported in
the manuscript, all potentially important factors when it
comes to endothelial dysfunction, coronary ﬂow mea-
surements, and the interrelation of diabetes and coronary
The conclusion of the current study is supported by
the published data: The overall blood ﬂow during stress
correlated independently with the left ventricular ejec-
tion fraction besides the diabetic status of the patients.
However, some missing facts limit the information
content of the paper:
Reprint requests: Michael J. Zellweger, MD, University Hospital,
Petersgraben 4, 4031, Basel, Switzerland; firstname.lastname@example.org;
J Nucl Cardiol 2017;24:1312–3.
Copyright Ó 2016 American Society of Nuclear Cardiology.