Cardiovascular Reserve Capacity In Patients Undergoing Hematopoietic Cell Transplantation

Abstract

PURPOSE:Cardiovascular disease (CVD) is a leading cause of morbidity and mortality in patients treated with hematopoietic cell transplantation (HCT), possibly due to depletion of cardiovascular reserve capacity (CVRC) induced by cancer treatment and pre-existing comorbidities. However, there is a paucity of information regarding pre-HCT CVRC, as measured by cardiopulmonary exercise testing (CPET). Less is known about the determinants of CVRC in patients planning to undergo HCT. METHODS: Consecutive patients (N=121) with hematological malignancies underwent symptom limited CPET at a single center <30 days prior to HCT. Patients were excluded if they had clinically significant CVD. Pulmonary function test (PFT) was performed on all participants, and body composition including fat/muscle mass was assessed using a bio-electrical impedance analyzer. Descriptive statistics were used to describe the characteristics of pre-HCT CVRC. Multivariable linear regression was performed to evaluate the relative contribution of PFT-obtained measures to the baseline determinants (age, resting heart rate; rHR, body fat mass) of CVRC. RESULTS: Mean age was 52 years (range: 20-76), 65% were male, 55% were non-Hispanic White, 39% were Hispanic; diagnoses included: acute leukemia (40%), lymphoma (27%) and multiple myeloma (21%). Mean peak expiratory flow (PEF): 7.1 (range:3.6-12.1), rHR: 78.6 bpm (range 51-124), body fat mass: 27.3kg (7.3-50.1). No adverse events were observed during CPET, and 91% were able to achieve peak effort (respiratory exchange ratio >1.10) or >90% of age-predicted heart rate). Among patients who achieved peak effort, mean relative VO 2 peak was 18.7 ml/kg/min (range:12.9-36.4); 76% of participants had impaired CVRC (VO 2 peak <80% of predicted) and 17% had VO 2 peak <16ml/kg/min. Age, rHR, fat mass explained 32% of the variance in VO 2 peak (R 2 : 0.32); the inclusion of PEF improved VO 2 peak prediction (R 2 : 0.41). CONCLUSION: A high proportion of patients planning to undergo HCT had markedly impaired CVRC. Integration of CPET and other physiological assessments prior to HCT may provide detailed characterization of CVRC that can inform prognosis in patients with hematological cancer undergoing HCT, setting the stage for evidence-based interventions to prevent future cardiovascular events.