Borlaug, Barry

Introduction: Heart failure (HF) with preserved ejection fraction (HFpEF) is now the predominant HF subtype, largely driven by the syndemic of physical inactivity and overweight/obesity in an aging population. Deranged skeletal muscle energetics and regional ectopic adipose depots are key cardiometabolic pathways in the pathogenesis of HFpEF, both of which may be favorably modified by 1-2 hours/week of resistance exercise (RE). However, its association with HFpEF risk has not been thoroughly examined. We investigated the association between midlife RE behaviors and incident HFpEF in the Atherosclerosis Risk in Communities (ARIC) study. Hypothesis: Participation in RE at midlife is inversely associated with the risk of incident HFpEF. Methods: Our exposure (RE)—including weightlifting and bodyweight resistance exercises—was assessed using the validated Baecke questionnaire and reported weekly RE duration was averaged across Visits 1 and 3 (1987-1995). We dichotomized averaged RE as 0 hr/wk (‘No RE’, reference) and >0 hr/wk (‘Any RE’). Our outcome (incident HFpEF) was identified through committee-adjudicated HF hospitalizations (January 1, 2005 to December 31, 2023) using medical chart abstraction. Participants with prevalent HF, death, or loss to follow-up before January 1, 2005 were excluded. We constructed Cox regression models to evaluate the association between midlife RE and incident HFpEF. Model 1 adjusted for age, sex, race, field center, education, smoking status, alcohol consumption, and non-RE physical activity. Given that adiposity may lie on the causal pathway, waist-height ratio (WHtR; both measured in cm) was added in Model 2. Results: 10,751 Black and White participants (803 incident HFpEF cases) were analyzed over a median follow-up time of 14.4 years (mean±SD Visit 1 age, 53.3±5.6 years; average Visit 1 and 3 WHtR, 0.58±0.08; 24.7% Black; 57.4% female). 1,217 participants (11.3%) reported engaging in RE at Visits 1 and/or 3, with a median duration of 0.84 hr/wk (IQR, 0.50-1.61). Compared to No RE, the fully adjusted hazard ratio (HR) for Model 1 for Any RE was: 0.78 (95% CI, 0.61-1.00, P = 0.05). The association was attenuated after adjustment for WHtR: HR = 0.84 (0.65-1.07, P = 0.16). Conclusion: Participation in RE at midlife is associated with a 22% lower risk of incident HFpEF. To inform public health and clinical guidelines, further studies are needed to clarify the role of RE in HFpEF prevention.

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 >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 >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.

Abstract Patients with heart failure with preserved ejection fraction (HFpEF) universally complain of exercise intolerance and dyspnoea as key clinical correlates. Cardiac as well as extracardiac components play a role for the limited exercise capacity, including an impaired cardiac and peripheral vascular reserve, a limitation in mechanical ventilation and/or gas exchange with reduced pulmonary vascular reserve, skeletal muscle dysfunction and iron deficiency/anaemia. Although most of these components can be differentiated and quantified through gas exchange analysis by cardiopulmonary exercise testing (CPET), the information provided by objective measures of exercise performance has not been systematically considered in the recent algorithms/scores for HFpEF diagnosis, by neither European nor US groups. The current clinical consensus statement by the Heart Failure Association (HFA) and European Association of Preventive Cardiology (EAPC) of the European Society of Cardiology (ESC) aims at outlining the role of exercise testing and its pathophysiological, clinical and prognostic insights, addressing the implications of a thorough functional evaluation from the diagnostic algorithm to the pathophysiology and treatment perspectives of HFpEF. Along with these goals, we provide a specific analysis of the evidence that CPET is the standard for assessing, quantifying, and differentiating the origin of dyspnoea and exercise impairment and even more so when combined with echocardiography and/or invasive haemodynamic evaluation. This will lead to improved quality of diagnosis when applying the proposed scores and may also help to implement the progressive characterization of the specific HFpEF phenotypes, a critical step toward the delivery of phenotype-specific treatments.

Background In heart failure, the exercise gas exchange Weber (A to D) and ventilatory classifications (VC‐1 to VC‐4) historically define disease severity and prognosis. However, their applications in the modern heart failure population of any left ventricular ejection fraction combined with hemodynamics are undefined. We aimed at revisiting and implementing these classifications by cardiopulmonary exercise testing imaging. Methods and Results 269 patients with heart failure with reduced (n=105), mid‐range (n=88) and preserved (n=76) ejection fraction underwent cardiopulmonary exercise testing imaging, primarily assessing the cardiac output (CO), mitral regurgitation, and mean pulmonary arterial pressure (mPAP)/CO slope. Within both classes, a progressively lower exercise CO, higher mPAP/CO slopes, and mitral regurgitation ( P <0.01 all) were observed. After adjustment for age and sex, Cox proportional hazard regression analyses showed that Weber (hazard ratio [HR], 2.9; 95% CI, 1.8–4.7; P <0.001) and ventilatory classes (HR, 1.4; 95% CI, 1.1–2.0; P =0.017) were independently associated with outcome. The best stratification was observed when combining Weber (A/B or C/D) with severe ventilation inefficiency (VC‐4) (HR, 2.7; 95% CI, 1.6–4.8; P <0.001). At multivariable analysis the best hemodynamic determinants of peak oxygen consumption and ventilation to carbon dioxide production slope were CO (β‐coefficient, 0.72±0.16; P <0.001) and mPAP/CO slope (β‐coefficient, 0.72±0.16; P <0.001), respectively. Conclusions In the contemporary heart failure population, the Weber and ventilatory classifications maintain their prognostic ability, especially when combined. Exercise CO and mPAP/CO slope are the best predictors of peak oxygen consumption and ventilation to carbon dioxide production slope classifications representing the main targets of interventions to impact functional class and, likely, event rate.

This is an analysis involving 134 heart failure patients with reduced ejection fraction versus 80 controls investigated during functional evaluation with gas exchange and hemodynamic, addressing the severe mitral regurgitation phenotype and testing the hypothesis that the backward cardiac output redistribution to the lung during exercise impairs delivery and overexpresses peripheral extraction. This information is new and has important implications in the management of heart failure.