Reddy, Yogesh N.V.

Abstract Aims While intentional weight loss achieved through cardiometabolic medications has been associated with robust salutary effects in heart failure (HF) with preserved ejection fraction (HFpEF), the clinical significance of unintentional weight loss in this setting remains unclear. Methods and results This retrospective cohort study included 434 overweight or obese patients with invasively proven HFpEF (67 ± 11 years, 236 female), without weight-reducing therapies or known malignancy, who underwent invasive hemodynamic cardiopulmonary testing and long-term clinical follow-up. The annualized weight change from index to final evaluation for the tertiles was: −21.1 to −1.8 kg/year (tertile 1); −1.8 to 0 kg/year (tertile 2); and 0 to +17.0 kg/year (tertile 3). Patients in tertile 1 had subtle abnormalities in ventilatory control at baseline, but there were no other significant differences between groups across a vast array of haemodynamic and metabolic parameters, both at rest and during exercise. Baseline weight was directly correlated with right and left heart filling pressures (r = 0.23–0.34, p < 0.001), but annualized weight change showed no correlation with any baseline haemodynamic measurements (all p > 0.05). Over a median follow-up of 4.7 years (interquartile range 2.3–6.5), patients in tertile 1 had higher risk of all-cause death (hazard ratio [HR] 3.36, 95% confidence interval [CI] 1.77–6.39, p < 0.001), all-cause death or HF hospitalization (HR 2.49, 95% CI 1.53–4.04, p < 0.001) and cardiac death or HF hospitalization (HR 2.28, 95% CI 1.28–4.07, p = 0.005) compared with those in tertile 2 or 3. These findings were consistent after multivariable adjustment. Conclusions Unintentional weight loss is associated with worse prognosis in patients with HFpEF and overweight or obesity, even as haemodynamics, exercise capacity, and gas exchange are not different from patients with stable or increasing weight. These data underline important and fundamental differences between therapeutic and unintended weight loss in HFpEF.

Abstract Aims Oxygen consumption at peak exercise is widely used to assess functional impairment in heart failure with preserved ejection fraction (HFpEF), but few patients exercise to this intensity in daily living. Alternative metrics that quantify submaximal fitness may provide more patient-centred evaluations, but the pathophysiology of submaximal exercise intolerance in HFpEF is unexplored. Methods and results Patients with HFpEF underwent invasive haemodynamic cardiopulmonary exercise testing with blood lactate measurement during exercise to volitional fatigue. Lactate threshold (LT) was defined as the exercise workload at which arterial lactate exceeded >2.0 mmol/L, taken as a measure of submaximal fitness. Of patients with HFpEF (n = 286), 194 (68%) reached LT at a workload of 40 W or less (LT ≤40 W), while 92 (32%) reached a workload exceeding 40 W at LT (LT >40 W). As compared to LT >40 W, patients with LT ≤40 W were more likely to be female, anaemic, and had greater pulmonary vascular disease (all p < 0.01). During 20 W exercise, participants with LT ≤40 W had higher pulmonary artery pressure, biventricular filling pressures, minute ventilation and respiratory drive, higher perceived dyspnoea and fatigue ratings, greater arterial–venous oxygen content difference, despite similar cardiac output and oxygen delivery. At peak exercise, most of these differences were no longer apparent. Findings were replicated using non-invasively-measured workload at ventilatory threshold. Conclusions Two-thirds of patients with HFpEF reach LT at workloads typical of activities of daily living. Patients with HFpEF and impaired submaximal fitness are more likely to be female, have greater pulmonary vascular disease and anaemia severity, and display greater haemodynamic, symptomatic, and ventilatory control abnormalities during low-level exercise, which are not apparent at maximal exertion. These findings have therapeutic implications and suggest a potentially important role for wider evaluation of submaximal fitness in addition to peak aerobic capacity.

Abstract Rationale A subset of patients with group 1 pulmonary hypertension (PH) have superimposed left heart abnormalities with unclear metabolic implications. Objectives To compare serum/transpulmonary metabolome between group 1 PH stratified by heart failure with preserved ejection fraction (HFpEF) probability. Methods Patients with group 1 PH were stratified into low (<25%) and high (⩾75%) HFpEF-ABA (age, body mass index, and atrial fibrillation) probability, with healthy control subjects and subjects with clinical HFpEF used for comparison of venous and transpulmonary metabolomics. Measurements and Main Results Group 1 PH + high HFpEF probability (n = 131) was associated with a significant increase in 207 metabolites (false discovery rate [FDR] P < 0.05 and fold change >1) (n = 193, t test) and a significant decrease in 231 metabolites (FDR P < 0.05 and fold change <1) (n = 193, t test) compared with group 1 PH + low HFpEF probability (n = 62). Group 1 PH + high HFpEF probability was associated with enhanced tryptophan metabolism with higher downstream kynurenine metabolite concentrations and lower serotonin concentrations (FDR P < 0.002 for all, n = 193, t test). Linoleate (precursor to arachidonic acid and prostaglandins) and arginine and homoarginine (precursors to nitric oxide) were all lower in group 1 PH + high HFpEF probability (FDR P < 0.03 for all, n = 193, t test). Metabolome changes in group 1 PH + high HFpEF probability overlapped with clinical HFpEF (n = 240) but were abnormal relative to control subjects (n = 85) (P < 0.0001 for all, n = 456, t test). There was no evidence of differential transpulmonary uptake/release of most metabolites, suggesting probable nonpulmonary origin (except for serotonin, interaction P = 0.04; and kynurenine, interaction P = 0.03; n = 433, mixed model). Conclusions Patients with group 1 PH + high HFpEF probability have a unique metabolome characterized by enhanced tryptophan-kynurenine pathway breakdown, deficiency of amino acids (such as glycine and serine), lower serotonin, and decreased prostaglandin and nitric oxide precursors. Despite fulfilling clinical criteria for group 1 PH, these metabolome changes were comparable with clinical HFpEF, supporting biological overlap between these two forms of PH.

BACKGROUND: Patients with lung disease, sleep apnea, and chronic thromboemboli can develop pulmonary hypertension, currently classified as group 3 or 4. Many of these patients also have risk factors for heart failure with preserved ejection fraction (HFpEF), but the optimal approach to identify the disease overlap remains unclear. METHODS: Pretest probability for HFpEF was determined using the HFpEF-ABA (age, body mass index, atrial fibrillation) algorithm among adjudicated group 3 or 4 patients at risk for pulmonary hypertension in the PVDOMICS study (Redefining Pulmonary Hypertension Through Pulmonary Vascular Disease Phenomics). Patients were stratified by current resting right heart catheterization criteria, and in a separate analysis, stratified only by HFpEF-ABA probability into low (<25%), intermediate, and high (≥75%) HFpEF probability groups. RESULTS: Among 598 patients with group 3 disease, 27% (n=161) had elevated pulmonary capillary wedge pressure (PCWP) with postcapillary pulmonary hypertension even at rest, which was associated with the highest exercise PCWP. However, regardless of this resting PCWP-based classification, a larger subset had intermediate-to-high HFpEF-ABA probabilities (32% [n=197] high and 57% [n=358] intermediate HFpEF probability). High HFpEF probability in group 3 disease was associated with higher resting and dynamic PCWP response to NO, fluid, and exercise ( P <0.0001 for all). These changes were comparable with more traditionally defined HFpEF without pulmonary vascular disease (n=61) but less severe than those with combined precapillary and postcapillary pulmonary hypertension HFpEF (n=31; interaction P =0.006). Increasing HFpEF probability in group 3 disease was associated with worse left heart remodeling, quality of life, 6-minute walk distance, and peak VO 2 ( P <0.0001 for all). Findings were replicated in group 4 disease (n=102). CONCLUSIONS: Quantifying pretest probability for HFpEF in patients with sleep apnea, lung disease, or chronic thromboemboli identifies a progressive gradient for dynamic PCWP abnormalities with worse functional status and quality of life. These subclinical left heart abnormalities are not universally detectable by resting right heart catheterization alone and call for further study of whether strategies to prevent or treat HFpEF might improve functional status in these patients with high risk of occult HFpEF.

Abstract Rationale: Although guidelines recommend the use of provocative testing to diagnose pulmonary venous hypertension (PVH) that is unapparent at normal resting right heart catheterization (RHC), the incremental value of provocative testing is unknown. We aim to evaluate the incremental diagnostic capability of inhaled nitric oxide (iNO), fluid challenge (FC) or invasive cardiopulmonary exercise testing (iCPET) to unmask PVH using previously defined hemodynamic cutoffs. Methods: We included subjects from the NHLBI-funded Pulmonary Vascular Disease Phenomics (PVDOMICS) study. Our analysis included patients with World Symposium on Pulmonary Hypertension (WSPH) Group 2 disease (G2PH) and G2PH comparators (WSPH Group 2 phenotype without a diagnosis of PH) as determined by the PI or adjudication panel. We then applied a protocol-driven provocative approach based on the feasibility of modalities available in most catheterization labs. Using a pulmonary capillary wedge pressure (PCWP) cutoff of &gt;15, frequencies were identified for subjects based on resting PCWP and with iNO. Frequencies were also identified for: those who received FC with a PCWP cutoff of ≥18 or those who received iCPET with PCWP cutoff of &gt;20 (upright) or &gt;25 (supine). Results: There were 419 subjects identified with WSPH Group 2 disease (Figure). Roughly half were found to have a PCWP &gt;15 during resting RHC (N = 207). Of the remaining subjects with a resting PCWP ≤15 (N = 150), 42 subjects were found to have a PCWP &gt;15 with iNO administration (40.0%). Of the remaining 63 subjects with PCWP ≤15 following iNO administration, nearly half (N = 26, 48.0%) demonstrated a PCWP ≥18 following FC while 8 subjects (14.8%) demonstrated an elevated PCWP following iCPET. Conclusions: There is a high proportion of G2PH patients (∼35%) who appear hemodynamically similar to precapillary PH at rest. Inhaled nitric oxide vasodilatory challenge unmasks G2PH in many patients. In situations where iNO does not disclose the G2PH phenotype, provocation with FC or iCPET can be useful as a supplementary provocative maneuver. Future directions will focus on agnostically assessing the utility of provocation based on grouping subjects by resting hemodynamics as well as assessing the use of provocation in other forms of PH.

Abstract Aims Left ventricular (LV) ventricular-arterial coupling (VAC) refers to the ratio of afterload (effective arterial elastance) to contractility (end-systolic elastance) as an integrated marker of cardiac performance. We sought to determine whether the echocardiographic VAC ratio, defined using the ratio of LV end-systolic volume (LVESV) to stroke volume (SV), predicted mortality in the cardiac intensive care unit (CICU). Methods and results Mayo Clinic CICU patients from 2007 and 2018 were included. Ventricular-arterial coupling ratio was calculated as the Teichholz LVESV divided by the SV calculated from LV outflow tract Doppler. The primary outcome was in-hospital mortality and the secondary outcome was all-cause 1-year mortality. A total of 4685 patients were included with a median age of 69 (58, 79) years (37.2% females), with acute coronary syndrome in 54.9% and heart failure in 49.0%. A higher VAC ratio was associated with greater severity of illness, worse echocardiographic findings, and more use of critical care therapies. A total of 329 (7%) patients died during hospitalization. Patients with a higher VAC ratio had higher in-hospital mortality overall and in each admission diagnosis subgroup. After multivariable adjustment, patients with a VAC ratio &gt;2 were at higher risk of in-hospital mortality (adjusted odds ratio 1.63, 95% confidence interval 1.17–2.28, P = 0.010). One-year mortality was higher for patients with a higher VAC ratio, especially VAC &gt;2. Conclusion Ventricular-arterial uncoupling was associated with worse outcomes in an unselected CICU cohort. The echocardiographic VAC ratio is a simple non-invasive bedside measure that can be used for risk prediction in the CICU.

BACKGROUND: Exercise-induced hypertension (EIH) is common in adults with coarctation of the aorta (COA), but there are limited data about hemodynamics and outcomes in such patients. The purpose of this study was to assess changes in arterial load during exercise in patients with COA with versus without EIH, and the relationship to clinical outcomes. METHODS: We compared Doppler-derived arterial load indices (effective arterial elastance index, total arterial compliance index, systemic vascular resistance index), and clinical indices of disease severity (pulmonary congestion, aerobic capacity, and cardiovascular biomarkers) between adults with repaired COA and healthy controls. EIH was defined as systolic blood pressure (BP) at peak exercise >210 mm Hg in men or >190 mm Hg in women. RESULTS: In this prospective cohort study, we assessed patients with COA (n=41, age 43±14 years, 26 [63%] men) and healthy controls (n=41). Although both groups had similar resting systolic BP, the COA group had higher Doppler-derived arterial load indices at rest, as well as a greater rise in systolic BP and Doppler-derived arterial load indices at each stage of exercise, leading to a higher prevalence of EIH in the COA group (37% versus 10%; P =0.004). Compared with patients with COA without EIH (n=26, 63%), those with EIH had higher arterial load at rest and during exercise, as well as worse cardiac dysfunction, pulmonary congestion, and biomarkers of cardiovascular remodeling, despite no significant differences in resting systolic BP. CONCLUSIONS: BP assessment during exercise can improve risk stratification and identify patients who may benefit from intensification of medical therapy.