Page 5 - Cardiac testing for coronary artery disease in potential kidney transplant recipients

B A C K G R O U N D
• Carotid intimal medial thickness (CIMT)
Kidney transplantation remains the best treatment for patients
• Cardiopulmonary exercise testing
with end-stage kidney disease (ESKD) in terms of prolonging sur-
• Computed tomography (CT) coronary angiography
vival and improving quality of life. However, research has shown
• Magnetic resonance angiography
that transplantation causes significant cardiovascular stress around
• Cardiac magnetic resonance imaging.
the time of the operation, and the incidence of myocardial in-
farction has been estimated to be approximately 5% (Gunnarsson
1984; Lentine 2005). Cardiovascular disease accounts for almost
half (40% to 55%) of all deaths following kidney transplanta- Rationale
tion (Briggs 2001). Screening for coronary artery disease (CAD) Severe CAD is strongly associated with the risk of myocardial in-
is therefore an important part of evaluation for kidney transplan- farction (MI) (Alderman 1993; Manoharan 2009). Non-invasive
tation and a key decision tool to identify which patients need cardiac screening tests may enable identification of kidney trans-
specialised heart imaging tests (coronary angiography) and when. plant candidates who are at high risk of significant CAD. Such
Clinical practice varies considerably in how patients are selected tests are therefore useful in triaging patients for coronary angiog-
for testing; some centres test only those patients with significant raphy, a test that provides confirmation of diagnosis and opportu-
risk factors, others test all kidney transplant candidates; and in nity for timely intervention (endovascular or open surgical inter-
which screening test is used (Hofmann 2008). The studies we vention, and aggressive risk factor modification, or both). There
reviewed used tests such as dobutamine stress echocardiography is significant controversy about which tests should be used in the
(DSE), myocardial perfusion scintigraphy (MPS) and stress elec- screening process (Hofmann 2008). Although coronary angiogra-
trocardiography (EST) versus radiographic tests such as calcium phy is the gold standard for detecting coronary artery stenosis, it is
scoring, among others (Hofmann 2008). invasive, costly, and carries risk of nephrotoxicity, arrhythmia, MI,
stroke and femoral artery injury. Although anatomical depiction
Clinical practice guidelines from the American Society of Trans-
derived from coronary angiography is a valuable diagnostic asset,
plantation (Kasiske 2001), United Kingdom Renal Association
the test does not provide perfusion or contractility information
(Dudley 2008) and Canadian Society of Transplantation (Knoll
when the heart is under physiological stress. Non-invasive inves-
2005) advise cardiac stress testing in potential transplant recipi-
tigations such as DSE and MPS have moderate sensitivity and
ents who have symptoms or significant risk factors, but do not rec-
specificity in detecting significant CAD in the general population
ommend a particular screening test. The guidelines indicate that
(Fleischmann 1998; Schinkel 2003). The applicability of these re-
the test should be determined by local availability and expertise.
sults in patients with ESKD who are potential kidney transplant
Although various screening tests for CAD are available, it remains
recipients is however uncertain. Common comorbidities among
unclear which tests perform best for patients with ESKD.
patients with chronic kidney disease (CKD) are hypertension, car-
diomyopathy, calcific vascular disease and atherosclerosis. Com-
pared with the general population, these comorbidities may influ-
Target condition being diagnosed
ence diagnostic test performance in people with CKD.
The target condition was significant CAD in potential kidney
transplant recipients. We defined significant CAD as the presence
of at least 50% stenosis in at least one epicardial coronary artery
detected on coronary angiography.
O B J E C T I V E S
We investigated the diagnostic accuracy of non-invasive cardiac
screening tests versus coronary angiography in potential kidney
Index test(s)
transplant recipients. We provided summary estimates of diagnos-
Any non- or minimally invasive test used to assess risk of CAD. tic accuracy for individual index tests to better understand the
These included: utility and limitations of these non-invasive tests.
• Stress echocardiography (using either exercise or
pharmacological stress, such as DSE)
• MPS using either exercise or pharmacological stress
Secondary objectives
• EST
• Electron beam computed tomography (EBCT) We compared the diagnostic accuracy among different screening
• Resting electrocardiography (ECG) tests through:
• Conventional echocardiography 1. Direct comparison: By analysing the results of studies that
• Exercise ventriculography assessed diagnostic accuracy of two or more tests in the same
• Digital subtraction fluorography (DSF) population head-to-head.

Cardiac testing for coronary artery disease in potential kidney transplant recipients (Review) 3
Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.