Abstract: FR-OR042
Exercise Cardiac MRI and Cardiopulmonary Testing Reveal Distinct Exercise Phenotypes and Dynamic Cardiac Impairment in CKD: CRUISE-CKD Study
Session Information
- Hypertension and Cardiorenal Disease: Novel Mechanisms and Therapeutic Targets
November 07, 2025 | Location: Room 332A, Convention Center
Abstract Time: 05:20 PM - 05:30 PM
Category: Hypertension and CVD
- 1602 Hypertension and CVD: Clinical
Authors
- Dobre, Mirela A., University Hospitals Health System, Cleveland, Ohio, United States
- Glidden, Michael D, University Hospitals Health System, Cleveland, Ohio, United States
- Kwun, Audrey, University Hospitals Health System, Cleveland, Ohio, United States
- Pollard, Jordan T, University Hospitals Health System, Cleveland, Ohio, United States
- Jenkins, Trevor L, University Hospitals Health System, Cleveland, Ohio, United States
- Cara, Elaine Ann, Case Western Reserve University, Cleveland, Ohio, United States
- Vergara-Martel, Armando, Case Western Reserve University, Cleveland, Ohio, United States
- Makhlouf, Mohamed, University Hospitals Health System, Cleveland, Ohio, United States
- Al-Kindi, Sadeer, Houston Methodist, Houston, Texas, United States
- Rajagopalan, Sanjay, University Hospitals Health System, Cleveland, Ohio, United States
Background
Dyspnea and exercise limitation are common in patients with CKD, yet the underlying mechanisms remain poorly understood. We developed a novel non-contrast exercise cardiac magnetic resonance (MR) imaging protocol combined with cardiopulmonary testing (ECMR-CPT) using an MR-compatible recumbent bike, to characterize structural and functional cardiac responses during acute exertion in CKD.
Methods
The CRUISE-CKD study prospectively enrolled 14 patients with CKD stages 3–4 (mean eGFR 32.6 ± 6.7 mL/min/1.73m2), and no history of heart failure. Participants underwent ECMR-CPT with measurement of biventricular volumes, systolic and diastolic function, pulmonary pressures, myocardial T1/T2 mapping (surrogates for fibrosis and edema), and cardiopulmonary metrics (maximum O2 consumption [VO2max], and ratio minute ventilation to CO2 consumption [VE/VCO2]) at rest and immediately post exercise.
Results
With exercise, significant increases were observed in left ventricle (LV) stroke volume (+12.7 mL), LV ejection fraction (EF) (+6.9%), cardiac output (+3.1 L/min), with marked inter-individual variability in biventricular response. Average VO2max improved by +6.64 ml/kg/min (mean peak 9.21 ml/kg/min), and the mean VE/VCO2 slope was 8.2, suggesting impaired ventilatory efficiency. Myocardial T1 values were elevated at rest, indicating subclinical fibrosis. T1 elevations and blunted right ventricle (RV) reserve with exertion were common and associated with lower VO2max. Two patients demonstrated exaggerated right heart response and signs suggestive of early exercise-induced pulmonary hypertension. A third of participants showed impaired contractile reserve and abnormal pulmonary hemodynamics during stress. Overall, ECMR-CPT revealed three distinct phenotypes: (1) preserved ejection fraction with impaired diastolic reserve, (2) RV-pulmonary vascular uncoupling, and (3) skeletal muscle-dominant limitation with preserved cardiac response.
Conclusion
Mechanisms beyond reduced GFR contribute to exercise intolerance in CKD. Our study highlights the value of dynamic imaging to reveal cardiac dysfunction not evident at rest and inform phenotype-guided interventions to improve functional outcomes in CKD.
Funding
- Private Foundation Support