Screening for Asymptomatic Coronary Artery Disease in Kidney Transplant Candidates

Overview

The Canadian Australasian Randomized Trial of Screening Kidney Transplant Candidates for Coronary Artery Disease (CARSK) will test the hypothesis that eliminating the regular use of non-invasive screening tests for CAD AFTER waitlist activation is not inferior to regular (i.e., annual) screening for CAD during wait-listing for the prevention of Major Adverse Cardiac Events. Secondary analyses will assess the impact of screening on the rate of transplantation, and the relative cost-effectiveness of screening.

Description

Cardiovascular disease is the commonest cause of death while on the kidney transplant waiting list and after transplantation. Current standard care involves screening for coronary artery disease prior to waitlist entry, then every 1-2 years, according to perceived risk, until transplanted. The aim of screening is two-fold. Firstly to identify patients with asymptomatic coronary disease to enable either correction, by bypass surgery or angioplasty, or removal of the patient from the list, with the ultimate aim of preventing premature cardiovascular mortality at the time of, or soon after kidney transplantation. Secondly, from a societal perspective, to prevent mis-direction of scarce donor organs into recipients who experience early mortality. This current screening strategy is not evidence based, has substantial known and potential harms, and is very costly. Two major issues of uncertainty require addressing in sequence: (1) whether to periodically screen asymptomatic wait-listed patients for occult coronary artery disease; and (2) whether to revascularise coronary stenoses in asymptomatic patients prior to transplantation. The CARSK study seeks to address the first of these 2 issues.

CARSK aims to

1. Test the hypothesis that after screening for wait list entry, no further screening for coronary artery disease (CAD) is non-inferior to the current standard care which is screening all asymptomatic wait-listed patients for CAD at regular intervals.
2. Compare the benefits and costs of not screening versus regular CAD screening from a health system perspective.

Eligibility

Inclusion Criteria:

1. adults aged 18 years of age or older
2. Dialysis-dependent kidney failure and currently being assessed for OR active on the kidney transplant waiting list
3. expected to require further screening for CAD prior to transplantation (by current standard of care);
4. able to give consent;
5. anticipated to undergo transplantation more than 12 months from date of enrolment

Exclusion Criteria:

1. patients with signs or symptoms suggestive of uncontrolled cardiac disease such as unstable coronary syndromes, decompensated heart failure, uncontrolled arrhythmia, and severe valvular heart disease;
2. patients who "on-hold" for transplantation due to a medical problem;
3. patients with other solid organ transplants;
4. multi-organ transplant candidates (e.g. kidney-pancreas transplant candidates);
5. patients with planned living donor transplant;
6. patients unable to give consent.