Background Obese and overweight body habitus are common among patients undergoing right heart catheterization for suspected pulmonary hypertension, but previous studies have described only patients with severe obesity. This study examined the effect of body habitus on intracardiac pressures, thermodilution cardiac output (TDCO), indirect Fick (iFick) cardiac output (CO), and pulmonary vascular resistance (PVR) in subjects with normal cardiopulmonary hemodynamics. Methods A retrospective analysis was conducted on healthy volunteers and patients referred for right heart catheterization for dyspnea of unknown origin with normal hemodynamics. Of the 65 subjects (53 ± 14 years; 51% female), 31% were normal weight, 49% were overweight, and 20% had obesity, as defined by a body mass index of 30-39.9 kg/m 2 . Mixed venous oxygen saturations and intracardiac pressures were compared across body mass index categories. Agreement between iFick CO calculated by 3 formulae, and TDCO and PVR was examined. Results No differences in intracardiac pressures were observed, but mixed venous oxygen saturations were lower in the obese group. iFick CO underestimated TDCO, particularly with the LaFarge formula, with a systematic difference of 0.33 L/min for every 1 L/min increase in CO. This difference was largest in the obese group—on average by 23% ± 10%, translating to an overestimation of PVR by 34% ± 16% on average. Conclusions In individuals without severe obesity, intracardiac pressures are not different, but mixed venous oxygen saturations are lower. Obesity confounds estimations of CO and PVR by iFick methods, which could result in inappropriate hemodynamic classification. These data can inform best practices in hemodynamic assessment of populations with obesity.
The spectrum of patients referred for suspected pulmonary arterial hypertension (PAH) includes a population with clinical features suggestive of pulmonary hypertension due to left heart disease (PH-LHD). Even after right heart catheterization (RHC) performed at rest, it can be a challenge to identify patients who will clearly benefit from PAH drug therapy. Therefore, the objective of this study was to evaluate the role of exercise RHC to influence decisions regarding prescription of PAH drug therapy in this population. A retrospective cohort study was conducted of older adults with risk factors for PH-LHD and suspected PH referred for exercise RHC. One year follow-up was conducted to record clinical outcomes, all changes in PAH drug therapy, and changes in patient-reported quality of life. The final cohort included 61 patients, mean age of 69 ± 10; 44% and 34% had a history of coronary artery disease and atrial fibrillation respectively. Exercise changed the proportional breakdown of hemodynamic diagnoses from 36% No PH, 44% PAH, and 20%PH-LHD at rest to 15% No PH, 36% PAH, and 49% PH-LHD. Although a significant proportion of patients were reclassified as PH-LHD, there was an overall increase in the proportion of patients receiving PAH drug therapy, particularly for those with PAH confirmed by exercise RHC. A total of 11 PAH drug prescriptions were employed before exercise RHC increasing to 24 after (p = 0.002). Patients receiving PAH therapy demonstrated significant improvement in self-reported quality of life. Exercise RHC appeared to influence selection of PAH drug therapy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.