Background Right ventricular (RV) failure from increased pulmonary vascular loading is a major cause of morbidity and mortality, yet its modulation by disease remains poorly understood. We tested the hypotheses that, unlike the systemic circulation, pulmonary vascular resistance (RPA) and compliance (CPA) are consistently and inversely related regardless of age, pulmonary hypertension (PH), or interstitial fibrosis, and that this relation may be changed by elevated pulmonary capillary wedge pressure (PCWP), augmenting RV pulsatile load. Methods and Results Several large clinical databases with right heart/pulmonary catheterization data were analyzed to determine the RPA-CPA relationship with PH, pulmonary fibrosis, patient age, and varying PCWP. Patients with suspected or documented PH (n=1009) and normal PCWP displayed a consistent RPA-CPA hyperbolic (inverse) dependence; CPA=0.564/(0.047+RPA), with a near constant resistance-compliance product (RC) (0.48±0.17 seconds). In the same patients, the systemic RC was highly variable. Severe pulmonary fibrosis (n=89) did not change the RPA-CPA relation. Increasing patient age led to a very small though statistically significant change in the relation. However, elevation of the PCWP (n=8142) had a larger impact, significantly lowering CPA for any RPA, and negatively correlating RC (p<0.0001). Conclusions PH and pulmonary fibrosis do not significantly change the hyperbolic dependence between RPA and CPA, while patient age has only minimal affects. This fixed relationship helps explain the difficulty of reducing total RV afterload by therapies that have modest impact on mean RPA. Higher PCWP appears to enhance net RV afterload by elevating pulsatile, relative to resistive load, and may contribute to RV dysfunction.

Heart failure, or congestive heart failure, is a condition in which the heart cannot supply the body's tissues with enough blood. The result is a cascade of changes that lead to severe fatigue, breathlessness and, ultimately, death. In the past quarter century, much progress has been made in understanding the molecular and cellular processes that contribute to heart failure, leading to the development of effective therapies. Despite this, chronic heart failure remains a major cause of illness and death. And because the condition becomes more common with increasing age, the number of affected individuals is rising with the rapidly ageing global population. New treatments that target disease mechanisms at the cellular and whole-organ level are needed to halt and reverse the devastating consequences of this disease.

Exposure to catecholamines and beta-receptor agonists used routinely during procedures and diagnostic tests can precipitate all the features of stress cardiomyopathy, including cardiac isoenzyme elevation, QTc interval prolongation, and rapidly reversible cardiac dysfunction. These observations strongly implicate excessive sympathetic stimulation as central to the pathogenesis of this unique syndrome.

Background There is a growing interest in the intersection of heart failure (HF) and frailty; however, estimates of the prevalence of frailty in HF vary widely. The purpose of this paper was to quantitatively synthesize published literature on the prevalence of frailty in HF and to examine the relationship between study characteristics (i.e. age and functional class) and the prevalence of frailty in HF. Methods The prevalence of frailty in HF, divided into Physical Frailty and Multidimensional Frailty measures, was synthesized across published studies using a random-effects meta-analysis of proportions approach. Meta-regression was performed to examine the influence of age and functional class (at the level of the study) on the prevalence of frailty. Results A total of 26 studies involving 6896 patients with HF were included in this meta-analysis. Despite considerable differences across studies, the overall estimated prevalence of frailty in HF was 44.5% (95% Confidence Interval, 36.2%–52.8%; z = 10.54; p < 0.001). The prevalence was slightly lower among studies using Physical Frailty measures (42.9%, z = 9.05; p < 0.001) and slightly higher among studies using Multidimensional Frailty measures (47.4%, z = 5.66; p < 0.001). There were no significant relationships between study age or functional class and prevalence of frailty. Conclusions Frailty affects almost half of patients with HF and is not necessarily a function of age or functional classification. Future work should focus on standardizing the measurement of frailty and on broadening the view of frailty beyond a strictly geriatric syndrome in HF.

Background Systemic sclerosis associated pulmonary artery hypertension (SScPAH) has a worse prognosis compared to idiopathic pulmonary arterial hypertension (IPAH), with a median survival of 3 years after diagnosis often due to right ventricular (RV) failure. We tested if SScPAH or systemic sclerosis related pulmonary hypertension with interstitial lung disease (SSc-ILD-PH) imposes a greater pulmonary vascular load than IPAH and/or leads to worse RV contractile function. Methods and Results We analyzed pulmonary artery pressures and mean flow in 282 patients with pulmonary hypertension (166 SScPAH, 49 SSc-ILD-PH, 67 IPAH). An inverse relation between pulmonary resistance (RPA) and compliance (CPA) was similar for all three groups, with a near constant resistance × compliance product. RV pressure-volume loops were measured in a subset, IPAH (n=5) and SScPAH (n=7) as well as SSc without PH (SSc-no-PH, n=7) to derive contractile indexes (end-systolic elastance [Ees] and preload recruitable stroke work [Msw]), measures of right ventricular load (arterial elastance [Ea]), and RV-pulmonary artery coupling (Ees/Ea). RV afterload was similar in SScPAH and IPAH (RPA=7.0±4.5 vs. 7.9±4.3 Wood units; Ea=0.9±0.4 vs. 1.2±0.5 mmHg/mL; CPA=2.4±1.5 vs. 1.7±1.1 mL/mmHg; p>0.3 for each). Though SScPAH did not have greater vascular stiffening compared to IPAH, RV contractility was more depressed (Ees=0.8±0.3 vs. 2.3±1.1, p<0.01; Msw=21±11 vs. 45±16, p=0.01), with differential RV-PA uncoupling (Ees/Ea=1.0±0.5 vs. 2.1±1.0, p=.03). This ratio was higher in SSc-no-PH (Ees/Ea = 2.3±1.2, p=0.02 vs. SScPAH). Conclusions RV dysfunction is worse in SScPAH compared to IPAH at similar afterload, and may be due to intrinsic systolic function rather than enhanced pulmonary vascular resistive and/or pulsatile loading.