Impaired Myocardial Oxygenation Response to Stress in Patients With Chronic Kidney Disease

Abstract

BackgroundCoronary artery disease and left ventricular hypertrophy are prevalent in the chronic kidney disease (CKD) and renal transplant (RT) population. Advances in cardiovascular magnetic resonance (CMR) with blood oxygen level–dependent (BOLD) technique provides capability to assess myocardial oxygenation as a measure of ischemia. We hypothesized that the myocardial oxygenation response to stress would be impaired in CKD and RT patients.Methods and ResultsFifty-three subjects (23 subjects with CKD, 10 RT recipients, 10 hypertensive (HT) controls, and 10 normal controls without known coronary artery disease) underwent CMR scanning. All groups had cine and BOLD CMR at 3 T. The RT and HT groups also had late gadolinium CMR to assess infarction/replacement fibrosis. The CKD group underwent 2-dimensional echocardiography strain to assess fibrosis. Myocardial oxygenation was measured at rest and under stress with adenosine (140 μg/kg per minute) using BOLD signal intensity. A total of 2898 myocardial segments (1200 segments in CKD patients, 552 segments in RT, 480 segments in HT, and 666 segments in normal controls) were compared using linear mixed modeling. Diabetes mellitus (P=0.47) and hypertension (P=0.57) were similar between CKD, RT, and HT groups. The mean BOLD signal intensity change was significantly lower in the CKD and RT groups compared to HT controls and normal controls (−0.89±10.63% in CKD versus 5.66±7.87% in RT versus 15.54±9.58% in HT controls versus 16.19±11.11% in normal controls, P<0.0001). BOLD signal intensity change was associated with estimated glomerular filtration rate (β=0.16, 95% CI=0.10 to 0.22, P<0.0001). Left ventricular mass index and left ventricular septal wall diameter were similar between the CKD predialysis, RT, and HT groups. None of the CKD patients had impaired global longitudinal strain and none of the RT group had late gadolinium hyperenhancement.ConclusionsMyocardial oxygenation response to stress is impaired in CKD patients and RT recipients without known coronary artery disease, and unlikely to be solely accounted for by the presence of diabetes mellitus, left ventricular hypertrophy, or myocardial scarring. The impaired myocardial oxygenation in CKD patients may be associated with declining renal function. Noncontrast BOLD CMR is a promising tool for detecting myocardial ischemia in the CKD population.

The impact of hematocrit on oxygenation-sensitive cardiovascular magnetic resonance

“…This observation could be explained by a decreased T2* effect in anemic patients. Another study observed a blunted myocardial oxygenation response to adenosine in patients with chronic kidney disease and renal transplant patients [ 13 ]. The authors attributed this finding to the possible presence of microvessel disease, as these patients have a higher incidence of cardiovascular events.…”

“…Such a protocol would not only be free of radiation and pharmacologic contrast agents, but would also require neither potentially dangerous vasodilators nor uncomfortable carbon dioxide levels adjusted by complicated and expensive breathing circuits [ 12 ]. OS-CMR is being utilized increasingly to investigate cardiac pathologies and offers an innovative and potentially clinically feasible diagnostic protocol together with breathing maneuvers [ 1 , 2 , 11 , 13 – 15 ].…”

Novel cardiovascular magnetic resonance oxygenation approaches in understanding pathophysiology of cardiac diseases

“…Recognizing the high mortality due to coronary artery disease in patients with chronic kidney disease (CKD), Parnham and colleagues investigated the myocardial oxygenation response to stress in CKD (pre‐dialysis and dialysis) patients and patients who underwent renal transplant without symptoms of cardiac disease, left ventricular dysfunction, or known epicardial coronary artery disease . As shown in Figure A, an impaired OS‐CMR signal intensity was observed in CKD patients compared to normal volunteers and patients with hypertension.…”

Cardiovascular effects of metabolic syndrome after transplantation: convergence of obesity and transplant-related factors

“…Finally, blood oxygen level–dependent CMRI has been used to detect myocardial ischemia by assessing the tissue oxygenation of myocardial segments at rest and under stress by blood oxygen level–dependent signal intensity. A recent study employing this technique found that patients with CKD, dialysis and renal transplant had impaired myocardial response to stress compared with hypertensive and normal control subjects [ 98 ]. More research is needed to learn about the ways that this promising and versatile technique can be applied to the detection of subclinical CV dysfunction in the pediatric transplant population.…”