Ventricular-Arterial Coupling in Chronic Heart Failure

Feasibility and prognostic significance of ventricular-arterial coupling after myocardial infarction: the RIGID-MI cohort

AIMS

The clinical significance and feasibility of the recently described non-invasive parameters exploring ventricular-arterial coupling (VAC) remain uncertain. This study aimed to assess VAC parameters for prognostic stratification in stable patients with left ventricular ejection fraction (LVEF) ≥40% following myocardial infarction (MI).

METHODS AND RESULTS

Between 2018 and 2021, patients with LVEF ≥40% were evaluated 1 month following MI using transthoracic echocardiography (TTE) and arterial tonometry at rest and after a handgrip test. VAC was studied via the ratio between arterial elastance (Ea) and end-systolic LV elastance (Ees) and between pulse wave velocity (PWV) and global longitudinal strain (GLS). Patients were followed for major adverse cardiovascular events (MACE): all-cause death, acute heart failure, stroke, AMI, and urgent cardiovascular hospitalization. Among the 374 patients included, Ea/Ees and PWV/GLS were obtained at rest for 354 (95%) and 253 patients (68%), respectively. Isometric exercise was workable in 335 patients (85%). During a median follow-up of 32 months (interquartile range: 16-42), 41 (11%) MACE occurred. Patients presenting MACE were significantly older and had a higher prevalence of peripheral arterial disease, lower GLS, higher Ea, PWV, and PWV/GLS ratio. The Ea/Ees ratio and standard TTE parameters during isometric exercise were not associated with MACE. After adjustment, the PWV/GLS ratio was the only VAC parameter independently associated with outcome. Receiver operating characteristic curve analysis identified a PWV/GLS ratio >0.70 (Youden's index = 0.37) as the best threshold to identify patients developing MACE: hazard ratio (95% confidence interval) = 2.2 (1.14-4.27), P = 0.02.

CONCLUSION

The PWV/GLS ratio, assessed 1 month after MI, identifies a group of patients at higher risk of MACE providing additional value on top of conventional non-invasive parameters.

Can the hemodynamic model in heart failure be restored based on analysis of ventricular-arterial coupling?

The hemodynamic model was inappropriate to explain the disappointing effect of vasodilation and the beneficial effect of beta-blockade in chronic heart failure. A more nuanced hemodynamic analysis, taking both steady and pulsatile hemodynamics into consideration, improves insight into these apparently enigmatic effects. Of particular interest is the velocity of early systolic flow as a determinant of left ventricular afterload. Several drugs, in particular beta-blockers, directly or indirectly, influence the velocity of early systolic flow. Thus, the hemodynamic model in heart failure may deserve reconsideration.

Effects of Synchronizing Foot Strike and Cardiac Phase on Exercise Hemodynamics in Patients With Cardiac Resynchronization Therapy: A Within-Subjects Pilot Study to Fine-Tune Cardio-Locomotor Coupling for Heart Failure

BACKGROUND

Despite advances in medical and cardiac resynchronization therapy (CRT), individuals with chronic congestive heart failure (CHF) have persistent symptoms, including exercise intolerance. Optimizing cardio-locomotor coupling may increase stroke volume and skeletal muscle perfusion as previously shown in healthy runners. Therefore, we tested the hypothesis that exercise stroke volume and cardiac output would be higher during fixed-paced walking when steps were synchronized with the diastolic compared with systolic portion of the cardiac cycle in patients with CHF and CRT.

METHODS

Ten participants (58±17 years of age; 40% female) with CHF and previously implanted CRT pacemakers completed 5-minute bouts of walking on a treadmill (range, 1.5-3 mph). Participants were randomly assigned to first walking to an auditory tone to synchronize their foot strike to either the systolic (0% or 100±15% of the R-R interval) or diastolic phase (45±15% of the R-R interval) of their cardiac cycle and underwent assessments of oxygen uptake (V̇o2; indirect calorimetry) and cardiac output (acetylene rebreathing). Data were compared through paired-samples t tests.

RESULTS

V̇o2 was similar between conditions (diastolic 1.02±0.44 versus systolic 1.05±0.42 L/min; P=0.299). Compared with systolic walking, stroke volume (diastolic 80±28 versus systolic 74±26 mL; P=0.003) and cardiac output (8.3±3.5 versus 7.9±3.4 L/min; P=0.004) were higher during diastolic walking; heart rate (paced) was not different between conditions. Mean arterial pressure was significantly lower during diastolic walking (85±12 versus 98±20 mm Hg; P=0.007).

CONCLUSIONS

In patients with CHF who have received CRT, diastolic stepping increases stroke volume and oxygen delivery and decreases afterload. We speculate that, if added to pacemakers, this cardio-locomotor coupling technology may maximize CRT efficiency and increase exercise participation and quality of life in patients with CHF.

Superiority of a Representative MRI Flow Waveform over Doppler Ultrasound for Aortic Wave Reflection Assessment in Children and Adolescents With/Without a History of Heart Disease

Wave separation analysis (WSA) reveals the impact of forward- and backward-running waves on the arterial pressure pulse, but the calculations require a flow waveform. This study investigated (1) the variability of the ascending aortic flow waveform in children and adolescents with/without a childhood heart disease history (CHD); (2) the accuracy of WSA obtained with a representative flow waveform (RepFlow), compared with the triangulation method and published ultrasound-derived adult representative flow; (3) the impact of limitations in Doppler ultrasound on WSA; and (4) generalizability of results to adults with a history of CHD. Phase contrast MRI was performed in youth without (n = 45, Group 1, 10-19 years) and with CHD (n = 79, Group 2, 7-18 years), and adults with CHD history (n = 29, Group 3, 19-59 years). Segmented aortic cross-sectional area was used as a surrogate for the central pressure waveform in WSA. A subject-specific virtual Doppler ultrasound was performed on MRI data by extracting velocities from a sample volume. Time/amplitude-normalized ascending aortic flow waveforms were highly consistent amongst all groups. WSA with RepFlow therefore yielded errors < 10% in all groups for reflected wave magnitude and return time. Absolute errors were typically 1.5-3 times greater with other methods, including subject-specific (best-case/virtual) Doppler ultrasound, for which velocity profile skewing introduced waveform errors. Our data suggest that RepFlow is the optimal approach for pressure-only WSA in children and adolescents with/without CHD, as well as adults with CHD history, and may even be more accurate than subject-specific Doppler ultrasound in the ascending aorta.

Identification and functional analysis of senescent cells in the cardiovascular system using omics approaches

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality worldwide, and senescent cells have emerged as key contributors to its pathogenesis. Senescent cells exhibit cell cycle arrest and secrete a range of proinflammatory factors, termed the senescence-associated secretory phenotype (SASP), which promotes tissue dysfunction and exacerbates CVD progression. Omics technologies, specifically transcriptomics and proteomics, offer powerful tools to uncover and define the molecular signatures of senescent cells in cardiovascular tissue. By analyzing the comprehensive molecular profiles of senescent cells, omics approaches can identify specific genetic alterations, gene expression patterns, protein abundances, and metabolite levels associated with senescence in CVD. These omics-based discoveries provide insights into the mechanisms underlying senescence-induced cardiovascular damage, facilitating the development of novel diagnostic biomarkers and therapeutic targets. Furthermore, integration of multiple omics data sets enables a systems-level understanding of senescence in CVD, paving the way for precision medicine approaches to prevent or treat cardiovascular aging and its associated complications.

Proteomic Correlates of the Urinary Protein/Creatinine Ratio in Heart Failure With Preserved Ejection Fraction

Proteinuria is common in heart failure with preserved ejection fraction (HFpEF), but its biologic correlates are poorly understood. We assessed the relation between 49 plasma proteins and the urinary protein/creatinine ratio (UPCR) in 365 participants in the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist Trial. Linear regression and network analysis were used to represent relations between protein biomarkers and UPCR. Higher UPCR was associated with older age, a greater proportion of female gender, smaller prevalence of previous myocardial infarction, and greater prevalence of diabetes, insulin use, smoking, and statin use, in addition to a lower estimated glomerular filtration rate, hematocrit, and diastolic blood pressure. Growth differentiation factor 15 (GDF-15; β = 0.15, p <0.0001), followed by N-terminal proatrial natriuretic peptide (NT-proANP; β = 0.774, p <0.0001), adiponectin (β = 0.0005, p <0.0001), fibroblast growth factor 23 (FGF-23, β = 0.177; p <0.0001), and soluble tumor necrosis factor receptors I (β = 0.002, p <0.0001) and II (β = 0.093, p <0.0001) revealed the strongest associations with UPCR. Network analysis showed that UPCR is linked to various proteins primarily through FGF-23, which, along with GDF-15, indicated node characteristics with strong connectivity, whereas UPCR did not. In a model that included FGF-23 and UPCR, the former was predictive of the risk of death or heart-failure hospital admission (standardized hazard ratio 1.83, 95% confidence interval 1.49 to 2.26, p <0.0001) and/or all-cause death (standardized hazard ratio 1.59, 95% confidence interval 1.22 to 2.07, p = 0.0005), whereas UPCR was not prognostic. Proteinuria in HFpEF exhibits distinct proteomic correlates, primarily through its association with FGF-23, a well-known prognostic marker in HFpEF. However, in contrast to FGF-23, UPCR does not hold independent prognostic value.

Effects of a mitochondrial-targeted ubiquinol on vascular function and exercise capacity in chronic kidney disease: a randomized controlled pilot study

Mitochondria-derived oxidative stress has been implicated in vascular and skeletal muscle abnormalities in chronic kidney disease (CKD). The purpose of this study was to investigate the effects of a mitochondria-targeted ubiquinol (MitoQ) on vascular function and exercise capacity in CKD. In this randomized controlled trial, 18 patients with CKD (means ± SE, age: 62 ± 3 yr and estimated glomerular filtration rate: 45 ± 3 mL/min/1.73 m2) received 4 wk of 20 mg/day MitoQ (MTQ group) or placebo (PLB). Outcomes assessed at baseline and follow-up included macrovascular function measured by flow-mediated dilation, microvascular function assessed by laser-Doppler flowmetry combined with intradermal microdialysis, aortic hemodynamics assessed by oscillometry, and exercise capacity assessed by cardiopulmonary exercise testing. Compared with PLB, MitoQ improved flow-mediated dilation (baseline vs. follow-up: MTQ, 2.4 ± 0.3% vs. 4.0 ± 0.9%, and PLB, 4.2 ± 1.0% vs. 2.5 ± 1.0%, P = 0.04). MitoQ improved microvascular function (change in cutaneous vascular conductance: MTQ 4.50 ± 2.57% vs. PLB -2.22 ± 2.67%, P = 0.053). Central aortic systolic and pulse pressures were unchanged; however, MitoQ prevented increases in augmentation pressures that were observed in the PLB group (P = 0.026). MitoQ did not affect exercise capacity. In conclusion, this study demonstrates the potential for a MitoQ to improve vascular function in CKD. The findings hold promise for future investigations of mitochondria-targeted therapies in CKD.NEW & NOTEWORTHY In this randomized controlled pilot study, we investigated the effects of a mitochondria-targeted ubiquinol (MitoQ) on vascular function and exercise capacity in chronic kidney disease. Our novel findings showed that 4-wk supplementation of MitoQ was well tolerated and improved macrovascular endothelial function, arterial hemodynamics, and microvascular function in patients with stage 3-4 chronic kidney disease. Our mechanistic findings also suggest that MitoQ improved microvascular function in part by reducing the NADPH oxidase contribution to vascular dysfunction.

Vascular function: a key player in hypertension

The major functions of the arterial system are to "efficiently deliver blood to the peripheral organs and maintain vascular homeostasis". Both the endothelial and medial layer contribute to the three major functions, namely, conversion of pulsatile to steady blood flow, appropriate distribution of blood flow to the target organs, and vascular protection and homeostasis. Vascular dysfunction contributes to the development of cardiovascular diseases through a combination of several mechanisms, including impaired coronary perfusion, cardiac systolic/diastolic dysfunction, microvascular damage, and abnormal hemodynamics in the arterial tree. The representative marker of endothelial function is flow-mediated vasodilatation and that of the medial layer function is pulse wave velocity, and that of the blood supply function of the arterial tree is the ankle-brachial pressure index. In hypertension, vascular dysfunction could also lead to the development of isolated systolic hypertension, isolated diastolic hypertension, and systolic/diastolic hypertension. Vascular dysfunction is involved in a vicious cycle with abnormal blood pressure variability. Furthermore, a vicious cycle may also exist between vascular dysfunction and hypertension. While the significances of vascular function tests to predict future cardiovascular events has been established in cases of hypertension, their usefulness in assessing the effectiveness of management of the vascular functions in hypertension on the cardiovascular outcomes has not yet been fully clarified. Thus, vascular dysfunction plays crucial roles in the pathophysiology of hypertension, and further research is warranted to establish strategies to improve vascular dysfunction in cases of hypertension. Vascular functions in the pathophysiology of hypertension. Vascular dysfunction and elevation of blood pressure are components of a vicious cycle even from their early stages, which including abnormal blood pressure variabilities. This vicious cycle is associated with hypertensive organ damage and also adverse cardiovascular outcomes. Strategies to break this vicious cycle have not yet been fully established.

Ventricular-arterial coupling (VAC) in a population-based cohort of middle-aged individuals: The STANISLAS cohort

BACKGROUND AND AIMS

Data exploring normal values of different ventricular-arterial coupling (VAC) parameters and their association with anthropometric and cardiovascular (CV) factors are scarce. We aim to report values of two different methods of VAC assessment according to age and sex and explore their association with CV factors within a large population-based cohort of middle-aged individuals.

METHODS

For 1333 (mean age 48 ± 14) individuals participating in the 4th visit of the STANISLAS cohort, VAC was assessed by two methods [1]: arterial elastance (Ea)/end-systolic elastance (Ees) and [2] Pulse wave velocity (PWV)/Global longitudinal strain (GLS).

RESULTS

The mean values of Ea/Ees and PWV/GLS were 1.06 ± 0.20 and 0.42 ± 0.12, respectively. The two methods of VAC assessment were poorly correlated (Pearson's correlation coefficient r = 0.14 (0.08; 0.19)). Increased PWV/GLS was associated with older age and a higher degree of cardiovascular risk factors (i.e., BMI, blood pressure, LDL, diabetes, hypertension) in the whole population as well as in the parent generation. In contrast, higher Ea/Ees were associated with decreasing age, and lower prevalence of risk factors in the whole cohort but neutrally associated with risk factors in the parent generation.

CONCLUSIONS

Higher PWV/GLS is significantly associated with CV factors regardless of age. In contrast, worse Ea/Ees is associated with a better CV risk profile when considering individuals aged 30 to 70 but neutrally associated with CV factors when considering only older patients. These results may suggest that PWV/GLS should preferably be used to explore VAC. In addition, age-individualized threshold of Ea/Ees should be used.

The Role of the Vasculature in Heart Failure

The contribution of the vasculature in the development and progression of heart failure (HF) syndromes is poorly understood and often neglected. Incorporating both arterial and venous systems, the vasculature plays a significant role in the regulation of blood flow throughout the body in meeting its metabolic requirements. A deterioration or imbalance between the cardiac and vascular interaction can precipitate acute decompensated HF in both preserved and reduced ejection fraction phenotypes. This is characterised by the increasingly recognised concept of ventricular-arterial coupling: a well-balanced relationship between ventricular and vascular stiffness, which has major implications in HF. Often, the cause of decompensation is unknown, with international guidelines mainly centred on arrhythmia, infection, acute coronary syndrome and its mechanical complications as common causes of decompensation; the vascular component is often underrecognised. A better understanding of the vascular contribution in cardiovascular failure can improve risk stratification, earlier diagnosis and facilitate earlier optimal treatment. This review focuses on the role of the vasculature by integrating the concepts of ventricular-arterial coupling, arterial stiffness and venous return in a failing heart.

Association of arterial properties with left ventricular morphology and function in the community

OBJECTIVES

Arterial structural and functional remodeling is recognized as a key determinant of incident heart failure, although the contribution of arterial properties on left ventricular (LV) remodeling is not fully studied. Aortic dilatation is an early manifestation of arterial remodeling and estimated pulse wave velocity (ePWV) is emerging as a simple measure of arterial stiffness. This study aimed to characterize the association of aortic size and ePWV with LV morphology and function.

METHODS

The study cohort consisted of 539 participants without overt cardiac disease who underwent extensive cardiovascular examination. Aortic root diameter was measured by two-dimensional echocardiography and ePWV was calculated from a regression equation using age and mean blood pressure. LV global longitudinal strain (LVGLS) was obtained by speckle-tracking echocardiography.

RESULTS

Aortic root diameter and ePWV were correlated with LV mass index and LVGLS, while only ePWV was related to E / e' ratio. In multivariable analysis, aortic root diameter and ePWV were significantly related to LV mass index and LVGLS (all P  < 0.05), and the association of aortic root size and ePWV with LVGLS was independent of LV mass index and E / e' ratio. Individuals with both aortic root enlargement and increased ePWV had significantly larger LV mass index and reduced LVGLS compared with those either or those with normal aortic size and ePWV (both P  < 0.05).

CONCLUSION

Aortic root size and ePWV were independently associated with unfavorable LV remodeling in individuals free of cardiac disease, which might provide useful information into the pathogenesis-linking arterial remodeling and heart failure.

Sex differences in microvascular function and arterial hemodynamics in nondialysis chronic kidney disease

Cardiovascular disease (CVD) is the leading cause of death in chronic kidney disease (CKD). Abnormal arterial hemodynamics contribute to CVD, a relationship that can be mediated by microvascular dysfunction. The purpose of this study was to investigate potential sex differences in arterial hemodynamics and microvascular dysfunction in patients with stages 3 to 4 CKD. Vascular function was assessed in 22 male (mean ± SD; age, 56 ± 13 yr) and 10 female (age, 63 ± 9 yr) patients. Arterial hemodynamics were acquired with combined tonometry and oscillometry. Skin blood flow was used as a model of microvascular function. Participants were instrumented with three microdialysis fibers for the delivery of 1) Ringer's solution; 2) superoxide dismutase mimetic, Tempol; and 3) nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, apocynin. Blood flow was measured via laser-Doppler flowmetry during standardized local heating (42°C). Central pulse pressure (mean ± SE; 62 ± 9 vs. 46 ± 3 mmHg; P = 0.01) and augmentation index (36 ± 3 vs. 26 ± 3%; P = 0.03) were higher in females. There was a trend for higher central systolic pressures in females (146 ± 9 vs. 131 ± 3 mmHg; P = 0.06). Females reported higher forward (39 ± 4 vs. 29 ± 2 mmHg; P = 0.004) and reflected (27 ± 3 vs. 19 ± 1 mmHg; P < 0.001) wave amplitudes. Cutaneous vascular function was impaired in females compared with males (77 ± 3 vs. 89 ± 1%, P = 0.001). Microvascular function was improved following the delivery of Tempol and apocynin in females but not in males. Female patients with CKD had poorer central hemodynamics and reduced microvascular function compared with their male counterparts. Oxidative stress may contribute to lower microvascular function observed in females.NEW & NOTEWORTHY There are limited data regarding the physiological mechanisms of potential sex differences in central hemodynamics and vascular function in chronic kidney disease (CKD). We report that older female patients with nondialysis CKD have higher central pulse pressures compared with male patients with CKD. In addition, older females with CKD have lower microvascular function compared with their male counterparts, and oxidative stress contributes to the lower microvascular function in older female patients with CKD.

Association between arterial stiffness and left ventricular diastolic function: A large population-based cross-sectional study

Background

The association between arterial stiffness and left ventricular (LV) diastolic function has been demonstrated in several studies, but the samples size in those studies was small. This study aims to verify this issue in a large number of study subjects.

Methods

A total of 7,013 consecutive participants (mean age 60.6 years and 43.3% female) who underwent both baPWV and transthoracic echocardiography were retrospectively analyzed. Subjects with significant cardiac structural abnormalities were excluded.

Results

There were significant correlations of baPWV with septal e′ velocity (r = – 0.408; P < 0.001), septal E/e′ (r = 0.349; P < 0.001), left atrial volume index (LAVI) (r = 0.122; P < 0.001) and maximal velocity of tricuspid valve regurgitation (TR Vmax) (r = 0.322; P < 0.001). The baPWV values increased proportionally with an increase in the number of LV diastolic indices meeting LV diastolic dysfunction criteria (P-for-trend < 0.001). In multivariable analyses with adjustment for confounding effects of various clinical covariates, higher baPWV was independently associated with septal e′ < 7 (odds ratio [OR], 1.30; 95% confidence interval [CI] 1.20–1.60; P < 0.001), septal E/e′ ≥ 15 (OR, 1.46; 95% CI, 1.21–1.78; P < 0.001), and TR Vmax > 2.8 m/s (OR, 1.60; 95% CI, 1.23–2.09; P < 0.001) but not with LAVI ≥ 34 mL/m² (OR, 0.89; 95% CI, 0.76–1.03; P = 0.123).

Conclusions

Increased arterial stiffness, as measured by baPWV, was associated with abnormal diastolic function parameters in a large number of study participants, providing strong evidence to the existing data about ventricular-vascular coupling.

Altered Aortic Hemodynamics and Relative Pressure in Patients with Dilated Cardiomyopathy

Ventricular-vascular interaction is central in the adaptation to cardiovascular disease. However, cardiomyopathy patients are predominantly monitored using cardiac biomarkers. The aim of this study is therefore to explore aortic function in dilated cardiomyopathy (DCM). Fourteen idiopathic DCM patients and 16 controls underwent cardiac magnetic resonance imaging, with aortic relative pressure derived using physics-based image processing and a virtual cohort utilized to assess the impact of cardiovascular properties on aortic behaviour. Subjects with reduced left ventricular systolic function had significantly reduced aortic relative pressure, increased aortic stiffness, and significantly delayed time-to-pressure peak duration. From the virtual cohort, aortic stiffness and aortic volumetric size were identified as key determinants of aortic relative pressure. As such, this study shows how advanced flow imaging and aortic hemodynamic evaluation could provide novel insights into the manifestation of DCM, with signs of both altered aortic structure and function derived in DCM using our proposed imaging protocol.

Sympathomodulation in Heart Failure with High vs. Normal Ejection Fraction

Background

Despite recent advances in the treatment of heart failure with preserved ejection fraction (HFpEF), the overall outcome is poor and evidence-based therapeutic options are scarce. So far, the only evidence-based therapy in HFpEF, sodium glucose linked transporter 2 inhibitors, has only insignificant effects in patients with a high EF (EF > 60%, HEF) when compared to a normal EF (EF 50%-60%, NEF). This could be explained by different biomechanical and cellular phenotypes of HFpEF across the range of EFs rather than a uniform pathophysiology. We aimed to investigate the concept of different phenotypes in the HEF and NEF using noninvasive single-beat estimations and to observe alterations in pressure-volume relations in both groups following sympathomodulation using renal denervation (RDN).

Methods

Patients from a previous study on RDN in HFpEF were stratified by having HFpEF with an HEF or NEF. Single-beat estimations were used to derive arterial elastance (Ea), end-systolic elastance (Ees), and diastolic capacitance (VPED₂₀).

Results

Overall, 63 patients were classified as having an HEF, and 36 patients were classified as having an NEF. Ea did not differ between the groups and was reduced at follow-up in both groups (p < 0.01). Ees was higher and VPED₂₀ was lower in the HEF than those in the NEF. Both were changed significantly at follow-up in the HEF but not in the NEF. Ees/Ea was lower in the NEF (0.95 ± 0.22 vs 1.15 ± 0.27, p < 0.01) and was significantly increased in the NEF (by 0.08 ± 0.20, p < 0.05) but not in the HEF.

Conclusions

Beneficial effects of RDN were observed in the NEF and HEF, supporting the further investigation of sympathomodulating treatments for HFpEF in future trials.

Pleiotropic vasoprotective effects of high-dose atorvastatin therapy in the context of achieving the target low-density lipoprotein cholesterol in patients after myocardial infarction

Aim. To study the lipid-lowering and pleiotropic vasoprotective effects of atorvastatin depending on the achievement of the target low-density lipoprotein cholesterol (LDL-C) level in patients after ST-segment elevation myocardial infarction (STEMI) within 48-week follow-up period.

Material and methods. A total of 125 patients with STEMI, randomized to receive atorvastatin 40 or 80 mg per day for 48 weeks, were examined. On days 7-9, after 24, 48 weeks, we performed biochemical blood tests, echocardiography, as well as assessed the carotid arteries and endothelial function. The subjects were divided into the following groups: high-efficiency therapy (HET) — 41 patients who reached target LDL-C at control visits; moderate-efficiency therapy (MET) — 35 patients who achieved target LDL-C at one visit; low-efficiency therapy effective (LET) — 49 people who did not reach the target LDL-C. Differences were considered significant at p<0,05.

Results. A decrease in detection rate of an elevated brain natriuretic peptide was found in HET group from 41,5 to 17% (p<0,01) and in MET group from 48,6 to 23% (p<0,01), while no changes in the LET were revealed. The glomerular filtration rate in the LET group decreased by 8% (p<0,01). In the HET group, a decrease in arterial elastance by 9,4%, intima-media thickness by 9,9%, a decrease in the frequency of a negative response and an increase in a positive response (p<0,05) were revealed.

Conclusion. The results demonstrate the importance of achieving target LDL-C for the most favorable dynamics of brain natriuretic peptide, structural and functional characteristics of the arterial system.

Systemic arterial pulsatility index (SAPi) predicts adverse outcomes in advanced heart failure patients

Ventriculo-arterial (VA) coupling has been shown to have physiologic importance in heart failure (HF). We hypothesized that the systemic arterial pulsatility index (SAPi), a measure that integrates pulse pressure and a proxy for left ventricular end-diastolic pressure, would be associated with adverse outcomes in advanced HF. We evaluated the SAPi ([systemic systolic blood pressure-systemic diastolic blood pressure]/pulmonary artery wedge pressure) obtained from the final hemodynamic measurement in patients randomized to therapy guided by a pulmonary arterial catheter (PAC) and with complete data in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial. Cox proportional hazards regression was performed for the outcomes of (a) death, transplant, left ventricular assist device (DTxLVAD) or hospitalization, (DTxLVADHF) and (b) DTxLVAD. Among 142 patients (mean age 56.8 ± 13.3 years, 30.3% female), the median SAPi was 2.57 (IQR 1.63-3.45). Increasing SAPi was associated with significant reductions in DTxLVAD (HR 0.60 per unit increase in SAPi, 95% CI 0.44-0.84) and DTxLVADHF (HR 0.81 per unit increase, 95% CI 0.70-0.95). Patients with a SAPi ≤ 2.57 had a marked increase in both outcomes, including more than twice the risk of DTxLVAD (HR 2.19, 95% CI 1.11-4.30) over 6 months. Among advanced heart failure patients with invasive hemodynamic monitoring in the ESCAPE trial, SAPi was strongly associated with adverse clinical outcomes. These findings support further investigation of the SAPi to guide treatment and prognosis in HF undergoing invasive hemodynamic monitoring.

Overcoming the Limits of Ejection Fraction and Ventricular-Arterial Coupling in Heart Failure

Left ventricular ejection fraction (LVEF) and ventricular-arterial coupling (VAC) [VAC = Ea/Ees; Ea: effective arterial elastance; Ees: left ventricle (LV) elastance] are both dimensionless ratios with important limitations, especially in heart failure setting. The LVEF to VAC relationship is a divergent non-linear function, having a point of intersection at the specific value of 0.62, where V0 = 0 ml (V0: the theoretical extrapolated value of the volume-axis intercept at end-systolic pressure 0 mmHg). For the dilated LV, both LVEF and VAC are highly dependent on V0 which is inconclusive when derived from single-beat Ees formulas. VAC simplification should be avoided. Revisiting the relationship between systolic time intervals (STI), pressure, and volumes could provide simple-to-use guiding formulas, affordable for daily clinical practice. We have analyzed by echocardiography the hemodynamics of 21 patients with severe symptomatic heart failure with reduced ejection (HFrEF) compared to 12 asymptomatic patients (at risk of heart failure with mild structural disease). The groups were unequivocally separated by ‘classic’ measures (LVEF, LV end-systolic volume (ESV), LV mass, STI). Chen's Ees formula was weakly correlated with LVEF and indexed ESV (ESVi) but better correlated to the pre-ejection period (PEP); PEP/total ejection time (PEP/TET); systolic blood pressure/PEP (SBP/PEP) (P < 0.001). Combining the predictability of the LVEF to the determinant role of SBP/PEP on the Ees variations, we obtained: (SBP^*LVEF)/PEP mm Hg/ms, with an improved R² value (R² = 0.848; P < 0.001). The strongest correlations to VAC were for LVEF (R = −0.849; R² = 0.722) and PEP/TET (R = 0.925; R² = 0.857). By multiple regression, the VAC was strongly predicted (N = 33): (R = 0.975; R² = 0.95): VAC = 0.553–0.009^*LVEF + 3.463^*PEP/TET, and natural logarithm: Ln (VAC) = 0.147–1.4563^*DBP/SBP^*0.9–0.010^*LVEF + 4.207^*PEP/TET (R = 0.987; R² = 0.975; P = 0) demonstrating its exclusive determinants: LVEF, PEP/TET, and DBP/SBP. Considering Ea as a known value, the VAC-derived Ees formula: Ees_d ≈ Ea/(0.553–0.009^*LVEF+3.463^*PEP/TET) was strongly correlated to Chen's Ees formula (R = 0.973; R² = 0.947) being based on SBP, ESV, LVEF, and PEP/TET and no exponential power. Thus, the new index supports our hypothesis, in the limited sample of patients with HFrEF. Indices like SBP/PEP, (SBP^*LVEF)/PEP, PEP/TET, and DBP/SBP deserve further experiments, underlining the major role of the forgotten STI.

Adverse fibrosis remodeling and aortopulmonary collateral flow are associated with poor Fontan outcomes

BACKGROUND

The extent and significance in of cardiac remodeling in Fontan patients are unclear and were the subject of this study.

METHODS

This retrospective cohort study compared cardiovascular magnetic resonance (CMR) imaging markers of cardiac function, myocardial fibrosis, and hemodynamics in young Fontan patients to controls.

RESULTS

Fifty-five Fontan patients and 44 healthy controls were included (median age 14 years (range 7-17 years) vs 13 years (range 4-14 years), p = 0.057). Fontan patients had a higher indexed end-diastolic ventricular volume (EDVI 129 ml/m2 vs 93 ml/m2, p < 0.001), and lower ejection fraction (EF 45% vs 58%, p < 0.001), circumferential (CS - 23.5% vs - 30.8%, p < 0.001), radial (6.4% vs 8.2%, p < 0.001), and longitudinal strain (- 13.3% vs - 24.8%, p < 0.001). Compared to healthy controls, Fontan patients had higher extracellular volume fraction (ECV) (26.3% vs 20.6%, p < 0.001) and native T1 (1041 ms vs 986 ms, p < 0.001). Patients with a dominant right ventricle demonstrated larger ventricles (EDVI 146 ml/m2 vs 120 ml/m2, p = 0.03), lower EF (41% vs 47%, p = 0.008), worse CS (- 20.1% vs - 25.6%, p = 0.003), and a trend towards higher ECV (28.3% versus 24.1%, p = 0.09). Worse EF and CS correlated with longer cumulative bypass (R = - 0.36, p = 0.003 and R = 0.46, p < 0.001), cross-clamp (R = - 0.41, p = 0.001 and R = 0.40, p = 0.003) and circulatory arrest times (R = - 0.42, p < 0.001 and R = 0.27, p = 0.03). T1 correlated with aortopulmonary collateral (APC) flow (R = 0.36, p = 0.009) which, in the linear regression model, was independent of ventricular morphology (p = 0.9) and EDVI (p = 0.2). The composite outcome (cardiac readmission, cardiac reintervention, Fontan failure or any clinically significant arrhythmia) was associated with increased native T1 (1063 ms vs 1026 ms, p = 0.029) and EDVI (146 ml/m2 vs 118 ml/m2, p = 0.013), as well as decreased EF (42% vs 46%, p = 0.045) and worse CS (- 22% vs - 25%, p = 0.029). APC flow (HR 5.5 CI 1.9-16.2, p = 0.002) was independently associated with the composite outcome, independent of ventricular morphology (HR 0.71 CI 0.30-1.69 p = 0.44) and T1 (HR1.006 CI 1.0-1.13, p = 0.07).

CONCLUSIONS

Pediatric Fontan patients have ventricular dysfunction, altered myocardial mechanics and increased fibrotic remodeling. Cumulative exposure to cardiopulmonary bypass and increased aortopulmonary collateral flow are associated with myocardial dysfunction and fibrosis. Cardiac dysfunction, fibrosis, and collateral flow are associated with adverse outcomes.

Prognostic value of left ventricular-arterial coupling estimated using echocardiography in dogs with myxomatous mitral valve disease

Background

The interaction between the left ventricle (LV) and systemic arterial systems, known as left ventricular‐arterial coupling (VAC), has been evaluated based on the effective arterial elastance (Ea) to LV end‐systolic elastance (Ees) ratio (Ea/Ees). The Ea reflects the total arterial load of LV, whereas Ees reflects the LV systolic function. A recent study found that inappropriate VAC based on increased Ea/Ees estimated by echocardiography is associated with advanced disease severity in dogs with myxomatous mitral valve disease (MMVD).

Hypothesis

Inappropriate VAC assessed by echocardiographic estimation of Ea/Ees is associated with a worse prognosis in dogs with MMVD.

Animals

Eighty‐nine dogs with MMVD.

Methods

Prospective cohort study. Dogs underwent echocardiographic examinations at enrollment. The Ea was estimated using the formula: mean blood pressure/(forward stroke volume/body weight). The Ees was estimated using the formula: mean blood pressure/(LV end‐systolic volume/body weight). The Ea/Ees was calculated.

Results

By end of study, 22 dogs died of cardiac‐related causes with 67 dogs censored. Dogs with increased Ea/Ees (Ea/Ees >0.34; median survival time, 527 days; 95% confidence interval [CI], 322 days‐not determinable) had a shorter survival time (P < .0001) than those without increased Ea/Ees (Ea/Ees ≤0.34; median survival time, >1112 days; 95% CI, not determinable). Multivariate Cox proportional hazard analysis showed that Ea/Ees, body weight, peak systolic mitral annular velocity, and the peak early diastolic transmitral velocity‐to‐peak early diastolic mitral annular velocity ratio were independent predictors of cardiac‐related death among echocardiographic indices.

Conclusions and Clinical Importance

Inappropriate VAC assessed based on echocardiographically‐estimated Ea/Ees is associated with a worse prognosis in dogs with MMVD.

Features and implications of higher systolic central than peripheral blood pressure in patients at very high risk of atherosclerotic cardiovascular disease

Peripheral blood pressure (PBP) is usually higher than central blood pressure (CBP) due to pulse amplification; however, it is not well understood why cuff-measured PBP can be lower than CBP estimated by the late systolic pressure of radial pulse waves. We explored the implications of systolic PBP-CBP (P-CBP) differences for cardiovascular (CV) prognosis. In total, 335 patients at very high risk of atherosclerotic cardiovascular disease (ASCVD) underwent automated applanation tonometry and brachial-ankle pulse wave velocity (baPWV), and they were classified into groups according to positive or negative systolic P-CBP differences. Between-group characteristics and clinical outcomes (the composite of coronary revascularization, stroke, heart failure hospitalization, and CV death) were evaluated. Patients with negative differences had significantly higher frequency of hypertension, coronary artery disease, higher ASCVD risk burden, and elevated N-terminal pro b-type natriuretic peptide. They had higher left atrial volume index (LAVI) and lower systolic mitral septal tissue velocity (TVI-s') than those with a positive difference. These patients showed higher systolic PBP and CBP, and a higher baPWV. Multivariable analysis indicated that TVI-s', LAVI, and ASCVD risk burden were independent determinants of such systolic P-CBP differences. During a median follow-up of 12.6 months, clinical outcomes were significantly related to a negative difference (11.5% vs. 3.4%, p = 0.014), and a systolic P-CBP difference ≤ -8 mmHg was associated with a threefold higher likelihood of poor prognosis. In patients at very high risk of ASCVD, systolic P-CBP difference was associated with cardiac dysfunction and ASCVD risk burden, allowing further risk stratification.

Ventriculo-arterial coupling in patients with stable ischemic heart disease undergoing percutaneous coronary intervention

To investigate ventriculo-arterial coupling (VAC) and its components (E_a, E_es) in patients with stable ischemic heart disease and changes following percutaneous coronary intervention (PCI). 129 patients with stable ischemic heart disease (SIHD) undergoing PCI (study group) and 40 individuals without IHD (control group) were enrolled. VAC was calculated using echocardiography method at baseline and 1, 3, and 6 months after PCI. A linear mixed-effects models with restricted maximum likelihood were used to assess the impact of PCI on E_a, E_es, VAC over 6-month follow-up. Mean age of the SIHD group was 67.8 ± 8.1 (years), and predominantly men (73.6%). In the SIHD group, baseline median E_a, E_es and VAC were 2.52 (IQR 1.89-3.28) (mmHg/ml), 3.87 (IQR 2.90-4.95) (mmHg/ml), and 0.64 (IQR 0.54-0.79), respectively. Patients with SIHD had significantly lower E_es and higher VAC when compared to the control group (p < 0.05). E_es (p = 0.01) and VAC (p < 0.001) were significantly improved over 6 month follow-up after PCI. Notably, the degree of VAC improvement appears to be related to stented artery (Table 3). VAC obtained from echocardiographic methodology demonstrated a significant increase in patients with SIHD at baseline. This observation may represent a plausible mechanism for the benefit of PCI in SIHD. Hence, VAC may be a feasible parameter in the assessment of patients with SIHD.

The Potential Therapeutic Role of Celastrol in Patients With Heart Failure With Preserved Ejection Fraction

Analysis of left ventricular systolic dysfunction remained at the centre of heart failure research for many years (also known as heart failure with reduced ejection fraction, HFrEF). Although more than 50% of all heart failure patients experience a form of heart failure characterised by preserved ejection fraction (HFpEF), the pathophysiological mechanisms leading to this form of heart failure remain not well-understood. Several evidence-based treatments for HFrEF are in routine use, but there are limited evidence-based therapies for HFpEF. The effects of these remain controversial, with current treatment options being limited to managing the associated symptoms and conditions. Accumulating evidence demonstrates that pro-inflammatory and oxidative stress pathways play key roles in the development and progression of HFpEF, such as the Unfolded Protein Response (UPR) and inducible nitric oxide synthase. Celastrol, derived from medicinal plants, is a bioactive compound with strong anti-inflammatory properties, which could deem it as fruitful in overcoming the effects of such dysregulated UPR. This literature review therefore focuses on Celastrol's anti-inflammatory and antioxidant activities, alongside its other potential therapeutic activities, and its ability to impede the pathways that are thought to be involved in the development of HFpEF, such as the JAK2/STAT pathway, to elucidate the potential therapeutic role of this bioactive compound, in the treatment of HFpEF.

Ventricular-arterial coupling: definition, pathophysiology and therapeutic targets in cardiovascular disease

INTRODUCTION

The heart and arterial system are equally affected by arteriosclerosis/atherosclerosis. There is a constant interaction between the left ventricular (LV) function and the arterial system, termed ventricular-arterial coupling (VAC), which reflects the global cardiovascular efficiency. VAC is traditionally assessed by echocardiography as the ratio of effective arterial elastance (E_a) over end-systolic elastance (E_es) (E_a/E_es). However, the concept of VAC is evolving and new methods have been proposed such as the ratio of pulse wave velocity (PWV) to global longitudinal strain (GLS) and myocardial work index.

AREA COVERED

This clinical review presents the hemodynamic background of VAC, its clinical implications and the impact of therapeutic interventions to normalize VAC. The review also summarizes the detrimental effects of cardio-metabolic risk factors on the aorta and LV, and provides an update on arterial load and its impact on LV function. The narrative review is based upon a systemic search of the bibliographic database PubMed for publications on VAC.

EXPERT OPINION

Newer methods such as PWV/GLS-ratio may be a superior marker of VAC than the traditional echocardiographic E_a/E_es in predicting target organ damage and its association with clinical outcomes. Novel anti-diabetic drugs and optimal antihypertensive treatment may normalize VAC in high-risk patients.

Mediation of Arterial Stiffness for Hyperuricemia-Related Decline of Cardiac Systolic Function in Healthy Men

Background: This prospective observational study examined whether hyperuricemia may be associated with impaired left ventricular (LV) systolic function and increased cardiac load resulting from increased arterial stiffness.

Methods and Results: In 1,880 middle-aged (mean [±SD] age 45±9 years) healthy men, serum uric acid (UA) levels, pre-ejection period/ejection time (PEP/ET) ratio, serum N-terminal pro B-type natriuretic peptide (NT-proBNP) levels, and brachial-ankle pulse wave velocity (baPWV) were measured at the start and end of the 3-year study period. Linear regression analysis revealed that serum UA levels measured at baseline were significantly associated with the PEP/ET ratio, but not with serum NT-proBNP levels, measured at baseline (β=0.73×10⁻¹, P<0.01) and at the end of the study period (β=0.68×10⁻¹, P<0.01). The change in the PEP/ET ratio during the study period was significantly greater in the High-UA (UA >7 mg/dL in 2009 and 2012) than Low-UA (UA ≤7 mg/dL in 2009 and 2012) group. Mediation analysis demonstrated both direct and indirect (via increases in baPWV) associations between serum UA measured at baseline and the PEP/ET ratio measured at the end of the study period.

Conclusions: In healthy middle-aged Japanese men, hyperuricemia may be associated with an accelerated decline in ventricular systolic function, both directly and indirectly, via increases in arterial stiffness.

Renal Sympathetic Denervation in Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

Arterial hypertension is the most common comorbidity in patients with heart failure with preserved ejection fraction (HFpEF) and mediates adverse hemodynamics through related aortic stiffness and increased pulsatile load. We aimed to investigate the clinical and hemodynamic implications of renal sympathetic denervation (RDN) in patients with HFpEF and uncontrolled arterial hypertension.

METHODS

Patients undergoing RDN between 2011 and 2018 in a single-center were retrospectively analyzed and classified as HFpEF (n=99) or no HF (n=65). Stroke volume index and aortic distensibility were measured through cardiac magnetic resonance imaging, and left ventricular (LV) systolic and diastolic properties were assessed echocardiographically.

RESULTS

At baseline, patients with HFpEF had higher stroke volume index (median 40 [interquartile range, 33-48] versus 33 [26-40] mL/m², P=0.002), pulse pressure (69 [63-77] versus 61 [55-67] mm Hg, P<0.001), but lower LV-VPES_100mm Hg (18 [10-28] versus 24 [15-40] mL, P=0.007) and aortic distensibility (1.5 [1.1-2.6] versus 2.7 [1.1-3.5] 10^-3 mm Hg^-1, P=0.013) as compared to no-HF patients. Systolic blood pressure decreased comparable in patients with HFpEF and no-HF patients following RDN (-9 [-16 to -2], P<0.001). After RDN stroke volume index (-3 [-9 to +3] mL/m², P=0.011) decreased and aortic distensibility (0.2 [-0.1 to +1.1] 10^-3 mm Hg^-1, P=0.007) and systolic stiffness (P<0.001) increased in HFpEF patients. LV diastolic stiffness and LV filling pressures as well as NT-proBNP (N-terminal pro-B-type natriuretic peptide) decreased after RDN in patients with HFpEF (P=0.032, P=0.043, and P<0.001, respectively).

CONCLUSIONS

Patients with HFpEF undergoing RDN showed increased stroke volume index, vascular, and LV stiffness as compared to no-HF patients. Following RDN those hemodynamic alterations and reduced systolic and diastolic LV stiffness were partly normalized, implying RDN might be a potential therapeutic strategy for arterial hypertension and HFpEF.

Echocardiographic estimation of left ventricular-arterial coupling in dogs with myxomatous mitral valve disease

Background

The effective arterial elastance (Ea) to left ventricular (LV) end‐systolic elastance (Ees) ratio (Ea/Ees) is an index of the interaction between LV and systemic arterial systems, left ventricular‐arterial coupling (VAC). The Ea is an index of total arterial load of the LV, whereas Ees is an index of LV systolic function. In humans, inappropriate VAC based on increased Ea/Ees estimated using echocardiography is associated with more advanced heart disease severity.

Hypothesis

Left ventricular‐arterial coupling assessed by echocardiographic estimation of Ea/Ees is associated with disease severity in dogs with myxomatous mitral valve disease (MMVD).

Animals

Ninety MMVD dogs and 61 healthy dogs.

Methods

Prospective cross‐sectional study. The MMVD dogs were classified into stages B1, B2, or C according to American College of Veterinary Internal Medicine guidelines. Effective arterial elastance was echocardiographically estimated using the formula: mean blood pressure/(forward stroke volume/body weight). End‐systolic elastance was echocardiographically estimated using the formula: mean blood pressure/(LV end‐systolic volume/body weight). The ratio Ea/Ees was calculated.

Results

The ratio Ea/Ees was higher in stage B2 dogs than in healthy dogs and dogs stage B1 (both P < .0001), and higher in stage C dogs than in healthy dogs and dogs in the other 2 stages (healthy vs C and B1 vs C, P < .0001; B2 vs C, P = .0005). Multivariable logistic regression analysis showed that Ea/Ees and the peak velocity of early diastolic transmitral flow to isovolumic relaxation time ratio were independent predictors of stage C among echocardiographic indices in MMVD dogs.

Conclusions and Clinical Importance

Inappropriate VAC assessed by echocardiographically estimated Ea/Ees is associated with advanced disease severity in dogs with MMVD.

Modification of ventriculo-arterial coupling by spironolactone in nonischemic dilated cardiomyopathy

Aims

We sought to clarify the role of ventriculo–arterial (V–A) coupling in the treatment of nonischemic dilated cardiomyopathy (NIDCM) by adding a mineralocorticoid receptor antagonist (MRA) to conventional anti‐failure therapy.

Methods and results

We employed cardiac magnetic resonance imaging to quantify left ventricular (LV) contractility and V–A coupling in normal subjects at rest (n = 11) and in patients with NIDCM (n = 12) before and after long term anti‐failure therapy, in which MRA was added to conventional anti‐failure therapy. After ≥6 months' treatment in NIDCM patients, LV volumes and mass decreased, and the LV ejection fraction increased from a median of 24% (17, 27) (interquartile range IQR) to 47 (42, 52) (P < 0.002), with a marked reduction in arterial elastance (Ea) from 2.89 mmHg/mL (2.34, 4.0) to 1.50 (1.29, 1.95) (P < 0.002), similar to Ea of normal subjects, 1.53 (1.34, 1.67) (P > 0.05). The V–A coupling ratio, Ea/end‐systolic elastance (single‐beat method), decreased by −1.08 (−1.96, −0.55), (P = 0.003), as did Ea/end‐systolic pressure/end‐systolic pressure ratio, −0.54 (0.35, 0.87), (P = 0.002). The preload recruitable stroke work (PRSW) increased as did PRSW indexed for Ea (both P = 0.002), which reflected ‘total circulatory performance’.

Conclusions

In NIDCM, adding MRA to conventional anti‐failure therapy markedly improved LV ejection fraction and reduced peripheral vascular resistance, due to both improved LV contractility and especially to enhanced V–A coupling, as Ea decreased to normal. Total circulatory performance was a sensitive indicator of both LV pump performance and the arterial loading conditions.

Intrinsic Frequencies of Carotid Pressure Waveforms Predict Heart Failure Events: The Framingham Heart Study

Supplemental Digital Content is available in the text.

Intrinsic frequencies (IFs) derived from arterial waveforms are associated with cardiovascular performance, aging, and prevalent cardiovascular disease (CVD). However, prognostic value of these novel measures is unknown. We hypothesized that IFs are associated with incident CVD risk. Our sample was drawn from the Framingham Heart Study Original, Offspring, and Third Generation Cohorts and included participants free of CVD at baseline (N=4700; mean age 52 years, 55% women). We extracted 2 dominant frequencies directly from a series of carotid pressure waves: the IF of the coupled heart and vascular system during systole (ω₁) and the IF of the decoupled vasculature during diastole (ω₂). Total frequency variation (Δω) was defined as the difference between ω₁ and ω₂. We used Cox proportional hazards regression models to relate IFs to incident CVD events during a mean follow-up of 10.6 years. In multivariable models adjusted for CVD risk factors, higher ω₁ (hazard ratio [HR], 1.14 [95% CI], 1.03–1.26]; P=0.01) and Δω (HR, 1.16 [95% CI, 1.03–1.30]; P=0.02) but lower ω₂ (HR, 0.87 [95% CI, 0.77–0.99]; P=0.03) were associated with higher risk for incident composite CVD events. In similarly adjusted models, higher ω₁ (HR, 1.23 [95% CI, 1.07–1.42]; P=0.004) and Δω (HR, 1.26 [95% CI, 1.05–1.50]; P=0.01) but lower ω₂ (HR, 0.81 [95% CI, 0.66–0.99]; P=0.04) were associated with higher risk for incident heart failure. IFs were not significantly associated with incident myocardial infarction or stroke. Novel IFs may represent valuable markers of heart failure risk in the community.

Left-Sided Ventricular-arterial Coupling and Volume Responsiveness in Septic Shock Patients

BACKGROUND

Suboptimal ventricular arterial coupling (VAC) is one of the pivotal determinants of inefficient heart performance despite appropriate administration of fluids or vasopressors in shocks. Here, we investigate the performance of VAC in patients who are unresponsive to fluid administration in septic shock.

METHODS

This is a retrospective observational study of septic shock patients (n = 35). VAC was evaluated by effective arterial elastance (EaI), left ventricular end-systolic elastance (EesI), and EaI/EesI. Septic shock patients successfully fluid resuscitated after pulse indicator continuous cardiac output (PiCCO) monitoring, defined as an increase in general end-diastolic ventricular volume (GEDVI) more than 10%, were divided into volume responsive (VVr), and volume unresponsive (VVur) groups based on a cardiac index increase above 10%. We hypothesize that two groups of patients will exhibit dissimilarities of VAC variation, defined as EaI/EesI variation (ΔEaI/EesI).

RESULTS

Variations of EaI (ΔEaI), and EaI/EesI (ΔEaI/EesI), and systemic vascular resistance index (ΔSVRI) were significantly lower in the VVr group than those in the VVur group (P < 0.05). Variations of cardiac index (ΔCI), stroke volume index (ΔSVI), and EesI (ΔEesI) were significantly higher in patients with ΔEaI/EesI ≤ 0. Concomitantly, ΔEaI and ΔSVRI were significantly diminished as compared with patients with ΔEaI/EesI > 0 (P < 0.05). ΔCI has an inverse relationship with both ΔEaI (r = -0.46, P = 0.006), ΔEaI/EesI (r = -0.65, P < 0.001), and ΔSVRI (r = -0.59, P < 0.001). We observed more patients who were fluid responsive in the ΔEaI/EesI ≤ 0 group than in the group with ΔEaI/EesI > 0 (88.89% vs. 26.92%, P = 0.01).

CONCLUSIONS

Variation of VAC is often related to suboptimal ventricular volume responsiveness among patients with septic shock.

Revisiting the relationship between left ventricular ejection fraction and ventricular-arterial coupling

The aim of this article was to analyse in‐depth the relationship between left ventricular (LV) ejection fraction (EF) (LVEF) and the most commonly used formulas for the calculation of LV elastance (Ees), volume intercept at 0 mmHg pressure (V0), effective arterial elastance (Ea), and ventricular–arterial coupling (VAC) as are validated today. We analyse the mathematical resulting consequences, raising the question on the physiological validity. To our knowledge, some of the following mathematical consequences have never been published. On the basis of studies demonstrating that normal LV dimensions and LVEF have a Gaussian unimodal distribution, we considered that the normal modal LVEF is 62% or very close to it. Expressed as a fraction, it is 0.62, that is, the reciprocal of the Phi number (namely, 1/Φ ~ 0.618). Applying Euclid's mathematical law on the extreme and mean ratio (the golden ratio), we studied the LVEF–VAC relationship in normal hearts. The simplification of the VAC formula (with V0 = 0) leads to false physiological results; V0 extraction from single‐beat Chen's formula leads to high negative results in normal subjects; based on the Euclid law, LVEF and Ea/Ees will be equal for a ratio value of 0.618 (62%) where V0 cannot be different from 0 mL; LVEF and VAC inverse relationship formula (Ea/Ees = 1/LVEF − 1) is reducible to a fundamental property of Phi: 1/Φ = (Φ − 1), being valid only if LVEF = VAC at a 0.618 value; according to this restriction, Vo can only be 0 mL, thus describing a very limited range. The Ea/Ees ratio, owing to its mathematical more dynamic behaviour, can be more sensitive than LVEF, being a valuable clinical tool in patients with heart failure (HF) with reduced EF, acute unstable haemodynamic situations, where Ees and Ea variations are disproportionate. However, the application is doubtful in HF with preserved EF where Ees and Ea may have same‐direction augmentation. The modified VAC formula suffers from oversimplification, reducing it to a dimensionless ratio, which is supposed to approximate non‐linear time‐varying functions. Thus, we advocate for caution and in‐depth understanding when using simplified formulas in clinical practice.

Ventricular-vascular coupling in heart failure with preserved ejection fraction: A systematic review and meta-analysis

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a complex disease underlined by impaired ventricular-vascular coupling (VVC).

OBJECTIVES

To evaluate the VVC ratio in HFpEF patients at rest and during exercise and compare it to the healthy and heart failure with reduced ejection fraction (HFrEF) controls.

METHODS

PubMed and EMBASE databases were searched for trials that matched the inclusion criteria. Random-effects models were used to estimate the pooled mean difference with 95% confidence interval using Open Meta[Analyst] software.

RESULTS

A total of 13 trials met the inclusion criteria. Although VVC ratio was comparable between HFpEF and healthy controls at rest, it was significantly lower in HFrEF compared to HFpEF. During exercise, there was a significant decline in VVC ratio in HFpEF (-0.119, 95% CI (-0.183 to -0.055), p<0.001).

CONCLUSION

VVC ratio, although 'preserved' at rest in HFpEF patients, was overtly impaired during exercise highlighting the importance of dynamic testing.

Galectin-3 and Arterial Stiffness in Patients with Heart Failure: A Pilot Study

BACKGROUND

Cardiac performance depends on optimum ventriculoarterial coupling which is impaired in patients with heart failure (HF). Galectin-3 is a mediator of myocardial fibrosis and remodeling, and is associated with clinical status in patients with chronic HF. We examined the association of arterial stiffness with galectin-3 levels in patients with HF of ischemic etiology.

METHODS

We consecutively enrolled 40 patients with stable ischemic HF and reduced ejection fraction. Central aortic stiffness was evaluated non-invasively by measuring carotid femoral pulse wave velocity (PWV). Among other factors, serum levels of galectin-3 and b-type natriuretic peptide (BNP) were measured.

RESULTS

The median galectin-3 levels in our study population were 12.9 (10.8-18.7) ng/ml and the mean PWV was 9.31±2.79 m/sec. There was significant association of galectin-3 levels with age (r=0.48, p=0.003), creatinine clearance (r=-0.66, p<0.001) and BNP levels (r=0.36, p=0.05). There was a significant association of galectin-3 levels with PWV (r=0.37, p=0.03) and patients with PWV above median also had significantly increased levels of galectin-3 compared with patients with lower values of PWV [16.1(11.8-25.2) vs. 12.1(10.5-14) ng/ml, p=0.03].

CONCLUSION

We found an association of arterial stiffness and PWV with galectin-3 levels in patients with chronic HF of ischemic etiology. These findings suggest a pathway driving arterial stiffening and myocardial remodelling in HF. This may provide insight into the mechanism determining prognosis and clinical status of patients with HF.

Research Priorities for Heart Failure With Preserved Ejection Fraction: National Heart, Lung, and Blood Institute Working Group Summary

Heart failure with preserved ejection fraction (HFpEF), a major public health problem that is rising in prevalence, is associated with high morbidity and mortality and is considered to be the greatest unmet need in cardiovascular medicine today because of a general lack of effective treatments. To address this challenging syndrome, the National Heart, Lung, and Blood Institute convened a working group made up of experts in HFpEF and novel research methodologies to discuss research gaps and to prioritize research directions over the next decade. Here, we summarize the discussion of the working group, followed by key recommendations for future research priorities. There was uniform recognition that HFpEF is a highly integrated, multiorgan, systemic disorder requiring a multipronged investigative approach in both humans and animal models to improve understanding of mechanisms and treatment of HFpEF. It was recognized that advances in the understanding of basic mechanisms and the roles of inflammation, macrovascular and microvascular dysfunction, fibrosis, and tissue remodeling are needed and ideally would be obtained from (1) improved animal models, including large animal models, which incorporate the effects of aging and associated comorbid conditions; (2) repositories of deeply phenotyped physiological data and human tissue, made accessible to researchers to enhance collaboration and research advances; and (3) novel research methods that take advantage of computational advances and multiscale modeling for the analysis of complex, high-density data across multiple domains. The working group emphasized the need for interactions among basic, translational, clinical, and epidemiological scientists and across organ systems and cell types, leveraging different areas or research focus, and between research centers. A network of collaborative centers to accelerate basic, translational, and clinical research of pathobiological mechanisms and treatment strategies in HFpEF was discussed as an example of a strategy to advance research progress. This resource would facilitate comprehensive, deep phenotyping of a multicenter HFpEF patient cohort with standardized protocols and a robust biorepository. The research priorities outlined in this document are meant to stimulate scientific advances in HFpEF by providing a road map for future collaborative investigations among a diverse group of scientists across multiple domains.

Brachial-Ankle Pulse Wave Velocity Versus Its Stiffness Index β-Transformed Value as Risk Marker for Cardiovascular Disease

Background

The difference in the predictive ability of the brachial‐ankle pulse wave velocity (baPWV) and its stiffness index β‐transformed value (β‐baPWV, ie, baPWV adjusted for the pulse pressure) for the development of pathophysiological abnormalities related to cardiovascular disease or future occurrence of cardiovascular disease was examined.

Methods and Results

In study 1, a 7‐year prospective observational study in cohorts of 3274 men and 3490 men, the area under the curve in the receiver operator characteristic curve analysis was higher for baPWV than for β‐baPWV for predicting the development of hypertension (0.73, 95% CI=0.70 to 0.75 versus 0.59, 95% CI=0.56 to 0.62; P<0.01) and/or the development of retinopathy (0.78, 95% CI=0.73 to 0.82 versus 0.66, 95% CI=0.60 to 0.71; P<0.01) by the end of the study period. During study 2, a 3‐year observation period on 511 patients with coronary artery disease, 72 cardiovascular events were confirmed. The C statistics of both markers for predicting the development of cardiovascular events were similar.

Conclusions

Stiffness index β transformation of the baPWV may attenuate the significance of the baPWV as a risk marker for development of pathophysiological abnormalities related to cardiovascular disease in male subjects.

Arterial Remodeling and Dysfunction in the ZSF1 Rat Model of Heart Failure With Preserved Ejection Fraction

BACKGROUND

The interplay between the stiffened heart and vessels has long been viewed as a core mechanism in heart failure with preserved ejection fraction, but the incremental vascular molecular remodeling mechanisms from systemic arterial hypertension to heart failure with preserved ejection fraction remain poorly investigated. Our aim was to characterize central arterial remodeling and dysfunction in ZSF1 obese rats and to compare it with hypertensive ZSF1 lean and healthy Wistar-Kyoto controls.

METHODS AND RESULTS

Twenty-week-old male ZSF1 obese (n=9), lean (n=9), and Wistar-Kyoto rats (n=9) underwent left ventricular pressure-volume loop evaluation and synchronous acquisition of ascending aortic flow and pressure. Aortic rings underwent functional evaluation, histology, and molecular biology studies. Although mean arterial pressure, characteristic aortic impedance, and reactivity to phenylephrine were similarly increased in hypertensive ZSF1 lean and obese, only ZSF1 obese showed impaired relaxation and upward-shifted end-diastolic pressure-volume relationships despite preserved systolic function indexes, denoting heart failure with preserved ejection fraction. ZSF1 obese phenotype further showed decreased aortic compliance, increased wave reflection, and impaired direct NO donor and endothelial-mediated vasodilation which were accompanied on structural and molecular grounds by aortic media thickening, higher collagen content and collagen/elastin ratio, increased fibronectin and α-5 integrin protein expression and upregulated TGF (transforming growth factor)-β and CTGF (connective tissue growth factor) levels.

CONCLUSIONS

Functional, molecular, and structural disturbances of central vessels and their potentially underlying pathways were newly characterized in experimental heart failure with preserved ejection fraction rendering the ZSF1 obese rat model suitable for preclinical testing.

Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure

Apelin plays important roles in cardiovascular homeostasis. However, its effects on the mechanoenergetics of heart failure (HF) are unavailable. We attempted to investigate the effects of apelin on the left ventricular-arterial coupling (VAC) and mechanical efficiency in rats with HF. HF was induced in rats by the ligation of the left coronary artery. The ischemic HF rats were treated with apelin or saline for 12 weeks. The sham-operated animals served as the control. The left ventricular (LV) afterload and the systolic and diastolic functions, as well as the mechanoenergetic indices were estimated from the pressure-volume loops. Myocardial fibrosis by Masson's trichrome staining, myocardial apoptosis by TUNEL, and collagen content in the aorta as well as media area in the aorta and the mesenteric arteries were determined. Our data indicated that HF rats manifested an increased arterial load (Ea), a declined systolic function (reduced ejection fraction, +dP/dt_max, end-systolic elastance, and stroke work), an abnormal diastolic function (elevated end-diastolic pressure, τ, and declined −dP/dt_max), and decreased mechanical efficiency. Apelin treatment improved those indices. Concomitantly, increased fibrosis in the LV myocardium and the aorta and enhanced apoptosis in the LV were partially restored by apelin treatment. A declined wall-to-lumen ratio in the mesenteric arteries of the untreated HF rats was further reduced in the apelin-treated group. We concluded that the rats with ischemic HF were characterized by deteriorated LV mechanoenergetics. Apelin improved mechanical efficiency, at least in part, due to the inhibiting cardiac fibrosis and apoptosis in the LV myocardium, reducing collagen deposition in the aorta and dilating the resistant artery.

Novel approaches to the management of chronic systolic heart failure: future directions and unanswered questions

Despite improvements in outcomes in the last few decades for heart failure (HF) with reduced ejection fraction (HFrEF), there still remains a need for novel therapies as many patients incompletely recover with existing therapies and progress to advanced HF. In this review, we will discuss recent advances in the management of HFrEF with a focus on upcoming therapies that hold the greatest promise for clinical use. We will discuss novel pharmacological therapies and areas of uncertainty with existing therapies. We will also discuss the potential utility and controversy surrounding novel interventions for HF such as percutaneous mitral valve repair, atrial fibrillation ablation, and other emerging interventions with positive signals for benefit in HFrEF. Finally, we will summarize the current state of stem cell and gene therapy for HFrEF and future directions.

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Ventriculo-arterial interaction may be assessed by Oscillatory Power Fraction

The rate of energy transfer from the left ventricle to the aorta is viewed in terms of mean power (MP) and total power (TP). The difference between MP and TP is due to the pulsatility of the circulation and is known as oscillatory power (OP). OP is considered the energy spent to accelerate the blood flow. The aim of this study was to investigate the baseline left ventricular oscillatory power fraction (OP/TP) and how this was affected by acute cardiovascular dysfunction and altered preload. Twenty-eight patients undergoing elective coronary artery bypass graft surgery were included. Before administration of anaesthesia, we simultaneously recorded an arterial pressure curve and instantaneous cardiac outflow with pulsed wave Doppler. Postoperatively, prior to extubation, these measurements were repeated in neutral, Trendelenburg and reverse-Trendelenburg position. The final measurements were taken on the awake patient the day after the operation. TP is the mean of the instantaneous product of the flow and pressure curves. MP was calculated by multiplying mean arterial pressure with mean cardiac output. The oscillatory power fraction is therefore calculated as (TP-MP)/TP. The oscillatory power fraction in neutral position decreased from 23% preoperatively to 16% immediately postoperatively (P<0·001) and increased again to 19% the first postoperative day (P = 0·001). The oscillatory power fraction also increased from 16% in neutral to 19% in Trendelenburg (P = 0·001) and decreased comparing to neutral, to 14% in reverse-Trendelenburg (P = 0·04). The oscillatory power fraction is situation-dependent and is influenced by both the operation and the altered preload.

Left ventricular and proximal aorta coupling in magnetic resonance imaging: aging together?

The importance of aorta-ventricular coupling in cardiovascular disease is recognized but underestimated. The contribution of the age-related decline in ascending aortic function compared with characteristic impedance and total peripheral resistance on left ventricular function and remodeling is poorly studied. Our aim was to evaluate the relation of proximal aortic distensibility and impedance with left ventricular geometry and function in asymptomatic individuals. We prospectively studied 100 subjects (47 men, 53 women, age: 20-84 yr). Aortic strain, distensibility, arch pulse wave velocity, characteristic impedance (Z_c), total peripheral resistance, left ventricular (LV) volumes and mass, wall stress, and peak global circumferential myocardial strain and strain rates were determined by MRI. Central pressures were measured from tonometry. E_a/E_v, an index of vascular-ventricular coupling, and LV wall stress were preserved across age- or aortic-stiffness-stratified groups. Static and pulsatile components of aortic load were differentially associated with age. Increased total vascular resistance was associated with decreased LV strain and increased concentric remodeling [ratio of LV mass to end-diastolic volume (M/V ratio)] in all individuals. In younger individuals (<45 yr), aortic distensibility was related to LV strain and concentric remodeling (M/V ratio), whereas Z_c was related to LV strain and concentric remodeling (M/V ratio) in older individuals (>45 yr). Early age-related stiffening of the ascending aorta is a component of LV afterload subsequently associated with increased aortic impedance and alterations in LV geometry, namely concentric remodeling, decreased myocardial strain, and increased stroke work such that LV wall stress and arterial-ventricular coupling are preserved. NEW & NOTEWORTHY Local flow and deformation can both be assessed with high precision noninvasively in the ascending aorta using MRI. Combined with central pressure measurement, they provide distensibility and impedance and simultaneous reference assessment of left ventricular deformation and geometry, hence a comprehensive evaluation of arterial-ventricular coupling to study physiology and disease.

Impact of Diabetes Mellitus on Ventricular Structure, Arterial Stiffness, and Pulsatile Hemodynamics in Heart Failure With Preserved Ejection Fraction

Background Heterogeneity in the underlying processes that contribute to heart failure with preserved ejection fraction ( HF p EF ) is increasingly recognized. Diabetes mellitus is a frequent comorbidity in HF p EF , but its impact on left ventricular and arterial structure and function in HF p EF is unknown. Methods and Results We assessed the impact of diabetes mellitus on left ventricular cellular and interstitial hypertrophy (assessed with cardiac magnetic resonance imaging, including T1 mapping pregadolinium and postgadolinium administration), arterial stiffness (assessed with arterial tonometry), and pulsatile arterial hemodynamics (assessed with in-office pressure-flow analyses and 24-hour ambulatory monitoring) among 53 subjects with HF p EF (32 diabetic and 21 nondiabetic subjects). Despite few differences in clinical characteristics, diabetic subjects with HFpEF exhibited a markedly greater left ventricular mass index (78.1 [95% CI , 70.4-85.9] g versus 63.6 [95% CI , 55.8-71.3] g; P=0.0093) and indexed extracellular volume (23.6 [95% CI , 21.2-26.1] mL/m2 versus 16.2 [95% CI , 13.1-19.4] mL/m2; P=0.0008). Pronounced aortic stiffening was also observed in the diabetic group (carotid-femoral pulse wave velocity, 11.86 [95% CI , 10.4-13.1] m/s versus 8.8 [95% CI , 7.5-10.1] m/s; P=0.0027), with an adverse pulsatile hemodynamic profile characterized by increased oscillatory power (315 [95% CI , 258-373] mW versus 190 [95% CI , 144-236] mW; P=0.0007), aortic characteristic impedance (0.154 [95% CI , 0.124-0.183] mm Hg/mL per second versus 0.096 [95% CI , 0.072-0.121] mm Hg/mL per second; P=0.0024), and forward (59.5 [95% CI , 52.8-66.1] mm Hg versus 40.1 [95% CI , 31.6-48.6] mm Hg; P=0.0010) and backward (19.6 [95% CI , 16.2-22.9] mm Hg versus 14.1 [95% CI , 10.9-17.3] mm Hg; P=0.0169) wave amplitude. Abnormal pulsatile hemodynamics were also evident in 24-hour ambulatory monitoring, despite the absence of significant differences in 24-hour systolic blood pressure between the groups. Conclusions Diabetes mellitus is a key determinant of left ventricular remodeling, arterial stiffness, adverse pulsatile hemodynamics, and ventricular-arterial interactions in HF p EF . Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT 01516346.

Vitamin K Status, Warfarin Use, and Arterial Stiffness in Heart Failure

Large artery stiffening contributes to the pathophysiology of heart failure (HF) and associated comorbidities. MGP (matrix Gla-protein) is a potent inhibitor of vascular calcification. MGP activation is vitamin K-dependent. We aimed (1) to compare dp-ucMGP (dephospho-uncarboxylated MGP) levels between subjects with HF with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) and subjects without HF; (2) to assess the relationship between dp-ucMGP levels and arterial stiffness; and (3) to assess the relationship between warfarin use, dp-ucMGP levels, and arterial stiffness in HF. We enrolled 348 subjects with HFpEF (n=96), HFrEF (n=53), or no HF (n=199). Carotid-femoral pulse wave velocity, a measure of large artery stiffness, was measured with arterial tonometry. Dp-ucMGP was measured with ELISA. Dp-ucMGP levels were greater in both HFrEF (582 pmol/L; 95% CI, 444-721 pmol/L) and HFpEF (549 pmol/L; 95% CI, 455-643 pmol/L) compared with controls (426 pmol/L; 95% CI, 377-475 pmol/L; ANCOVA P=0.0067). Levels of dp-ucMGP were positively associated with carotid-femoral pulse wave velocity (standardized β, 0.31; 95% CI, 0.19-0.42; P<0.0001), which was also true in analyses restricted to patients with HF (standardized β, 0.34; 95% CI, 0.16-0.52; P=0.0002). Warfarin use was significantly associated with carotid-femoral pulse wave velocity (standardized β, 0.13; 95% CI, 0.004-0.26; P=0.043), but this relationship was eliminated after adjustment for dp-ucMGP. In conclusion, levels of dp-ucMGP are increased in HFpEF and HFrEF and are independently associated with arterial stiffness. Future studies should investigate whether vitamin K supplementation represents a suitable therapeutic strategy to prevent or reduce arterial stiffness in HFpEF and HFrEF.

Left ventricular-arterial coupling is associated with prolonged mechanical ventilation in severe post-cardiac surgery patients: an observational study

Background

Weaning post-cardiac surgery patients from mechanical ventilation (MV) poses a big challenge to these patients. Optimized left ventricular-arterial coupling (VAC) may be crucial for reducing the MV duration of these patients. However, there is no research exploring the relationship between VAC and the duration of MV. We performed this study to investigate the relationship between left ventricular-arterial coupling (VAC) and prolonged mechanical ventilation (MV) in severe post-cardiac surgery patients.

Methods

This was a single-center retrospective study of 56 severe post-cardiac surgery patients from January 2015 to December 2017 at the Department of Critical Care Medicine of Peking Union Medical College Hospital. Patients were divided into two groups according to the duration of MV (PMV group: prolonged mechanical ventilation group, MV > 6 days; Non-PMV group: non-prolonged mechanical ventilation group, MV ≤ 6 days). Hemodynamics and tissue perfusion data were collected or calculated at admission (T0) and 48 h after admission (T1) to the ICU.

Results

In terms of hemodynamic and tissue perfusion data, there were no differences between the two groups at admission (T0). Compared with the non-prolonged MV group after 48 h in the ICU (T1), the prolonged MV group had significantly higher values for heart rate (108 ± 13 vs 97 ± 12, P = 0.018), lactate (2.42 ± 1.24 vs.1.46 ± 0.58, P < 0.001), and Ea/Ees (5.93 ± 1.81 vs. 4.05 ± 1.20, P < 0.001). Increased Ea/Ees (odds ratio, 7.305; 95% CI, 1.181–45.168; P = 0.032) and lactate at T1 (odds ratio, 17.796; 95% CI, 1.377–229.988; P = 0.027) were independently associated with prolonged MV. There was a significant relationship between Ea/Ees_T1 and the duration of MV (r = 0.512, P < 0.01). The area under the receiver operating characteristic (AUC) of the left VAC for predicting prolonged MV was 0.801, and the cutoff value for Ea/Ees was 5.12, with 65.0% sensitivity and 90.0% specificity.

Conclusions

Left ventricular-arterial coupling was associated with prolonged mechanical ventilation in severe post-cardiac surgery patients. The assessment and optimization of left VAC might be helpful in reducing duration of MV in these patients.