The Role of the Pericardium in Heart Failure: Implications for Pathophysiology and Treatment

Small Left Ventricular Size Is a Risk Factor for Recurrent Pericardial Effusion after Percutaneous Drainage

Background: Significant pericardial effusion requires percutaneous drainage. Some patients experience recurrent pericardial effusion following index drainage, but its risk factors remain unknown. Such knowledge should further improve the clinical management of individuals presenting with pericardial effusion for risk stratification and the construction of therapeutic and management strategies beforehand. Methods: Patients who underwent percutaneous drainage for pericardial effusion between 2018 and 2023 were retrospectively included and were followed for 2 years or until November 2023. Baseline factors associated with recurrent pericardial effusion that required percutaneous drainage again were investigated to identify the high-risk cohort. Results: A total of 39 patients (83 years on median, 28 males) were included. During the 2-year observation period, 11 patients had the primary outcome. The left ventricular end-diastolic diameter at baseline was independently associated with the primary outcome with an adjusted hazard ratio of 0.88 (95% confidence interval 0.80-0.97, p = 0.013) with a cutoff of 42 mm, which significantly stratified the cumulative incidence of the primary outcome (53% versus 10%, p = 0.011). Conclusions: Recurrent pericardial effusion after percutaneous drainage is not a rare phenomenon. A smaller left ventricular endo-diastolic diameter was an independent risk factor for recurrent pericardial effusion. The clinical implications of our findings in daily clinical practice should be validated in future prospective studies. Further studies are warranted to clarify the underlying causality between them.

Nitroprusside Combined with Leg Raise at the Time of Right Heart Catheterization to Differentiate Precapillary from Other Hemodynamic Forms of Pulmonary Hypertension: A Single-Center Pilot Study

Pulmonary hypertension (PH) can arise from several distinct disease processes, with a percentage presenting with combined pre- and postcapillary pulmonary hypertension (cpcPH). Patients with cpcPH are unsuitable candidates for PH-directed therapies due to elevated pulmonary capillary wedge pressures (PCWPs); however, the PCWP is dynamic and is affected by both preload and afterload. Many patients that are diagnosed with cpcPH are hypertensive at the time of right heart catheterization which has the potential to increase the PCWP and, therefore, mimic a more postcapillary-predominant phenotype. In this small pilot study, we examine the effect of nitroprusside combined with dynamic preload augmentation with a passive leg raise maneuver in hypertensive cpcPH patients at the time of right heart catheterization to identify a more precapillary-dominant PH phenotype. Patients that met the criteria of PCWP ≤ 15 mmHg with nitroprusside infusion and PCWP ≤ 18 mmHg with nitroprusside infusion and simultaneous leg raise were started on pulmonary vascular-targeted therapy. Long-term PH therapy was well tolerated, with increased six-minute walk distance, improved WHO functional class, decreased NT-proBNP, and improved REVEAL 2.0 Lite Risk Score in this precapillary-dominant PH phenotype. This small study highlights the importance of characterizing patient physiology beyond resting conditions at the time of right heart catheterization.

Congestion patterns in severe tricuspid regurgitation and transcatheter treatment: Insights from a multicentre registry

AIMS

While invasively determined congestion holds mechanistic and prognostic significance in acute heart failure (HF), its role in patients with tricuspid regurgitation (TR)-related right- heart failure (HF) undergoing transcatheter tricuspid valve intervention (TTVI) is less well established. A comprehensive understanding of congestion patterns might aid in procedural planning, risk stratification, and the identification of patients who may benefit from adjunctive therapies before undergoing TTVI. The aim of this study was to investigate the role of congestion patterns in patients with severe TR and its implications for TTVI.

METHODS AND RESULTS

Within a multicentre, international TTVI registry, 813 patients underwent right heart catheterization (RHC) prior to TTVI and were followed up to 24 months. The median age was 80 (interquartile range 76-83) years and 54% were women. Both mean right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) were associated with 2-year mortality on Cox regression analyses with Youden index-derived cut-offs of 17 mmHg and 19 mmHg, respectively (p < 0.01 for all). However, RAP emerged as an independent predictor of outcomes following multivariable adjustments. Pre-interventionally, 42% of patients were classified as euvolaemic (RAP <17 mmHg, PCWP <19 mmHg), 23% as having left-sided congestion (RAP <17 mmHg, PCWP ≥19 mmHg), 8% as right-sided congestion (RAP ≥17 mmHg, PCWP <19 mmHg), and 27% as bilateral congestion (RAP ≥17 mmHg, PCWP ≥19 mmHg). Patients with right-sided or bilateral congestion had the lowest procedural success rates and shortest survival times. Congestion patterns allowed for discerning specific patient's physiology and specifying prognostic implications of right ventricular to pulmonary artery coupling surrogates.

CONCLUSION

In this large cohort of invasively characterized patients undergoing TTVI, congestion patterns involving right-sided congestion were associated with low procedural success and higher mortality rates after TTVI. Whether pre-interventional reduction of right-sided congestion can improve outcomes after TTVI should be established in dedicated studies.

Atrial and ventricular strain using cardiovascular magnetic resonance in the prediction of outcomes of pericarditis patients: a pilot study

OBJECTIVE

Our study aimed to explore with cardiovascular magnetic resonance (CMR) the impact of left atrial (LA) and left ventricular (LV) myocardial strain in patients with acute pericarditis and to investigate their possible prognostic significance in adverse outcomes.

METHOD

This retrospective study performed CMR scans in 36 consecutive patients with acute pericarditis (24 males, age 52 [23-52]). The primary endpoint was the combination of recurrent pericarditis, constrictive pericarditis, and surgery for pericardial diseases defined as pericardial events. Atrial and ventricular strain function were performed on conventional cine SSFP sequences.

RESULTS

After a median follow-up time of 16 months (interquartile range [13-24]), 12 patients with acute pericarditis reached the primary endpoint. In multivariable Cox regression analysis, LA reservoir and LA conduit strain parameters were all independent determinants of adverse pericardial diseases. Conversely, LV myocardial strain parameters did not remain an independent predictor of outcome. With receiving operating characteristics curve analysis, LA conduit and reservoir strain showed excellent predictive performance (area under the curve of 0.914 and 0.895, respectively) for outcome prediction at 12 months.

CONCLUSION

LA reservoir and conduit mechanisms on CMR are independently associated with a higher risk of adverse pericardial events. Including atrial strain parameters in the management of acute pericarditis may improve risk stratification.

CLINICAL RELEVANCE STATEMENT

Atrial strain could be a suitable non-invasive and non-contrast cardiovascular magnetic resonance parameter for predicting adverse pericardial complications in patients with acute pericarditis.

KEY POINTS

• Myocardial strain is a well-validated CMR parameter for risk stratification in cardiovascular diseases. • LA reservoir and conduit functions are significantly associated with adverse pericardial events. • Atrial strain may serve as an additional non-contrast CMR parameter for stratifying patients with acute pericarditis.

Biatrial myopathy in heart failure with preserved ejection fraction

AIM

Left atrial (LA) myopathy is increasingly recognized as an important phenotypic trait in heart failure (HF) with preserved ejection fraction (HFpEF). Right atrial (RA) remodelling and dysfunction also develop in HFpEF, but little data are available regarding the clinical characteristics and pathophysiology among patients with isolated LA, RA, or biatrial myopathy.

METHODS AND RESULTS

Patients with HFpEF underwent invasive haemodynamic exercise testing, comprehensive imaging including speckle tracking strain echocardiography, and clinical follow-up at Mayo Clinic between 2006 and 2018. LA myopathy was defined as LA volume index >34 ml/m2 and/or LA reservoir strain ≤24% and RA myopathy by RA volume index >39 ml/m2 in men and >33 ml/m2 in women and/or RA reservoir strain ≤19.8%. Of 476 consecutively evaluated patients with HFpEF defined by invasive exercise testing with evaluable atrial structure/function, 125 (26%) had no atrial myopathy, 147 (31%) had isolated LA myopathy, 184 (39%) had biatrial myopathy, and 20 (4%) had isolated RA myopathy. Patients with HFpEF and biatrial myopathy had more atrial fibrillation, poorer left ventricular systolic and diastolic function, more severe pulmonary vascular disease, tricuspid regurgitation, ventricular interdependence and right ventricular dysfunction, and poorer cardiac output reserve with exercise. There were 94 patients with events over a median follow-up of 2.9 (interquartile range 1.4-4.6) years. Individuals with biatrial myopathy had an 84% higher risk of HF hospitalization or death as compared to those with isolated LA myopathy (hazard ratio 1.84; 95% confidence interval 1.16-2.92, p = 0.01).

CONCLUSIONS

Biatrial myopathy identifies patients with more advanced HFpEF characterized by more severe pulmonary vascular disease, right HF, poorer cardiac reserve, and a greater risk for adverse outcomes. Further study is required to define optimal strategies to treat and prevent biatrial myopathy in HFpEF.

Heart Failure with Preserved Ejection Fraction: The Pathophysiological Mechanisms behind the Clinical Phenotypes and the Therapeutic Approach

Heart failure (HF) with preserved ejection fraction (HFpEF) is an increasingly frequent form and is estimated to be the dominant form of HF. On the other hand, HFpEF is a syndrome with systemic involvement, and it is characterized by multiple cardiac and extracardiac pathophysiological alterations. The increasing prevalence is currently reaching epidemic levels, thereby making HFpEF one of the greatest challenges facing cardiovascular medicine today. Compared to HF with reduced ejection fraction (HFrEF), the medical attitude in the case of HFpEF was a relaxed one towards the disease, despite the fact that it is much more complex, with many problems related to the identification of physiopathogenetic mechanisms and optimal methods of treatment. The current medical challenge is to develop effective therapeutic strategies, because patients suffering from HFpEF have symptoms and quality of life comparable to those with reduced ejection fraction, but the specific medication for HFrEF is ineffective in this situation; for this, we must first understand the pathological mechanisms in detail and correlate them with the clinical presentation. Another important aspect of HFpEF is the diversity of patients that can be identified under the umbrella of this syndrome. Thus, before being able to test and develop effective therapies, we must succeed in grouping patients into several categories, called phenotypes, depending on the pathological pathways and clinical features. This narrative review critiques issues related to the definition, etiology, clinical features, and pathophysiology of HFpEF. We tried to describe in as much detail as possible the clinical and biological phenotypes recognized in the literature in order to better understand the current therapeutic approach and the reason for the limited effectiveness. We have also highlighted possible pathological pathways that can be targeted by the latest research in this field.

Left Atrial Remodeling Related to Disproportionately Low B-Type Natriuretic Peptide in Acute Heart Failure Patients with Atrial Fibrillation

The diagnostic performance of B-type natriuretic peptide (BNP) for acute heart failure (HF) is impaired in patients with atrial fibrillation (AF). Increased AF burden in HF is associated with left atrial (LA) remodeling. Recent studies have revealed that LA remodeling may affect LV filling. We hypothesized that LA remodeling affects BNP secretion in acute HF conditions. The study investigated the clinical impact of LA remodeling on admission BNP levels in acute HF patients with and without AF. Consecutive acute HF hospitalized patients (n = 899) were divided into groups with (n = 382) or without AF (n = 507) and subdivided into disproportionately low BNP (LB) (≤200 pg/ml), medium BNP (200 to 600 pg/ml) and high BNP (≥600 pg/ml) subgroups. The AF group had a higher proportion of patients with LB than the non-AF group (23.6% vs 16.6%, p = 0.009). BNP levels in both groups were positively correlated with LV end-diastolic volume and negatively correlated with LV ejection fraction in both groups. In contrast, BNP was positively correlated with LA volume index in the non-AF group, but negatively correlated in the AF group. The survival rates were significantly higher in the LB group than in the other groups in non-AF. Conversely, there were no significant differences across all groups in AF patients. In conclusion, in patients with acute HF and AF, disproportionately low BNP levels are associated with LA structural remodeling and poor prognosis.

Increased Chamber Resting Tone Is a Key Determinant of Left Ventricular Diastolic Dysfunction

BACKGROUND

Twitch-independent tension has been demonstrated in cardiomyocytes, but its role in heart failure (HF) is unclear. We aimed to address twitch-independent tension as a source of diastolic dysfunction by isolating the effects of chamber resting tone (RT) from impaired relaxation and stiffness.

METHODS

We invasively monitored pressure-volume data during cardiopulmonary exercise in 20 patients with hypertrophic cardiomyopathy, 17 control subjects, and 35 patients with HF with preserved ejection fraction. To measure RT, we developed a new method to fit continuous pressure-volume measurements, and first validated it in a computational model of loss of cMyBP-C (myosin binding protein-C).

RESULTS

In hypertrophic cardiomyopathy, RT (estimated marginal mean [95% CI]) was 3.4 (0.4-6.4) mm Hg, increasing to 18.5 (15.5-21.5) mm Hg with exercise (P<0.001). At peak exercise, RT was responsible for 64% (53%-76%) of end-diastolic pressure, whereas incomplete relaxation and stiffness accounted for the rest. RT correlated with the levels of NT-proBNP (N-terminal pro-B-type natriuretic peptide; R=0.57; P=0.02) and with pulmonary wedge pressure but following different slopes at rest and during exercise (R2=0.49; P<0.001). In controls, RT was 0.0 mm Hg and 1.2 (0.3-2.8) mm Hg in HF with preserved ejection fraction patients and was also exacerbated by exercise. In silico, RT increased in parallel to the loss of cMyBP-C function and correlated with twitch-independent myofilament tension (R=0.997).

CONCLUSIONS

Augmented RT is the major cause of LV diastolic chamber dysfunction in hypertrophic cardiomyopathy and HF with preserved ejection fraction. RT transients determine diastolic pressures, pulmonary pressures, and functional capacity to a greater extent than relaxation and stiffness abnormalities. These findings support antimyosin agents for treating HF.

Obesity Modifies Clinical Outcomes of Right Ventricular Dysfunction

BACKGROUND

Right ventricular (RV) dysfunction is associated with increased mortality across a spectrum of cardiovascular diseases. The role of obesity in RV dysfunction and adverse outcomes is unclear.

METHODS

We examined patients undergoing right heart catheterization between 2005 and 2016 in a hospital-based cohort. Linear regression was used to examine the association of obesity with hemodynamic indices of RV dysfunction (pulmonary artery pulsatility index, right atrial pressure:pulmonary capillary wedge pressure ratio, RV stroke work index). Cox models were used to examine the association of RV function measures with clinical outcomes.

RESULTS

Among 8285 patients (mean age, 63 years; 40% women), higher body mass index was associated with worse indices of RV dysfunction, including lower pulmonary artery pulsatility index (β, -0.23; SE, 0.01; P<0.001), higher right atrium:pulmonary capillary wedge pressure ratio (β, 0.25; SE, 0.01; P<0.001), and lower RV stroke work index (β, -0.05; SE, 0.01; P<0.001). Over median of 7.3 years of follow-up, we observed 3006 mortality and 2004 heart failure hospitalization events. RV dysfunction was associated with a greater risk of mortality (eg, pulmonary artery pulsatility index:hazard ratio, 1.11 per 1-SD increase [95% CI, 1.04-1.18]), with similar associations with risk of heart failure hospitalization. Body mass index modified the effect of RV dysfunction on all-cause mortality (Pinteraction≤0.005 for PAPi and RA:PCWP ratio), such that the effect of RV dysfunction was more pronounced at higher body mass index.

CONCLUSIONS

Patients with obesity had worse hemodynamic measured indices of RV function across a broad hospital-based sample. While RV dysfunction was associated with worse clinical outcomes including mortality and heart failure hospitalization, this association was especially pronounced among individuals with higher body mass index.

Haemodynamic and metabolic phenotyping of patients with aortic stenosis and preserved ejection fraction: A specific phenotype of heart failure with preserved ejection fraction?

AIMS

Degenerative aortic valve stenosis with preserved ejection fraction (ASpEF) and heart failure with preserved ejection fraction (HFpEF) display intriguing similarities. This study aimed to provide a non-invasive, comparative analysis of ASpEF versus HFpEF at rest and during exercise.

METHODS AND RESULTS

We prospectively enrolled 148 patients with HFpEF and 150 patients with degenerative moderate-to-severe ASpEF, together with 66 age- and sex-matched healthy controls. All subjects received a comprehensive evaluation at rest and 351/364 (96%) performed a combined cardiopulmonary exercise stress echocardiography test. Patients with ASpEF eligible for transcatheter aortic valve replacement (n = 125) also performed cardiac computed tomography (CT). HFpEF and ASpEF patients showed similar demographic distribution and biohumoral profiles. Most patients with ASpEF (134/150, 89%) had severe high-gradient aortic stenosis; 6/150 (4%) had normal-flow, low-gradient ASpEF, while 10/150 (7%) had low-flow, low-gradient ASpEF. Both patient groups displayed significantly lower peak oxygen consumption (VO2 ), peak cardiac output, and peak arteriovenous oxygen difference compared to controls (all p < 0.01). ASpEF patients showed several extravalvular abnormalities at rest and during exercise, similar to HFpEF (all p < 0.01 vs. controls). Epicardial adipose tissue (EAT) thickness was significantly greater in ASpEF than HFpEF and was inversely correlated with peak VO2 in all groups. In ASpEF, EAT was directly related to echocardiography-derived disease severity and CT-derived aortic valve calcium burden.

CONCLUSION

Functional capacity is similarly impaired in ASpEF and HFpEF due to both peripheral and central components. Further investigation is warranted to determine whether extravalvular alterations may affect disease progression and prognosis in ASpEF even after valve intervention, which could support the concept of ASpEF as a specific sub-phenotype of HFpEF.

Obesity in Heart Failure with Reduced Ejection Fraction: Time to Address the Elephant in the Room

Obesity has been long recognized as a risk factor for the development of heart failure, but recent evidence suggests obesity is more typically associated with heart failure with preserved ejection fraction as opposed to heart failure with reduced ejection fraction (HFrEF). Nevertheless, numerous studies have found that obesity modulates the presentation and progression of HFrEF and may contribute to the development of HFrEF in some patients. Although obesity has definite negative effects in HFrEF patients, the effects of intentional weight loss in HFrEF patients with obesity have been poorly studied.

Obesity, Cardiorenal Comorbidities, and Risk of Hospitalization in Patients With Heart Failure With Preserved Ejection Fraction

OBJECTIVE

To compare clinical features of patients with obesity-related heart failure (HF) with preserved ejection fraction (HFpEF) with those of patients with similar body mass index (BMI) but no HF and to examine the association between degree of obesity and risk for hospitalizations.

METHODS

This was a retrospective analysis of 22,750 adults from a large US electronic health care data set (January 1, 2012, through July 31, 2019), including 4975 with HFpEF. Baseline characteristics were compared between patients with HFpEF and a control group matched on BMI, age, sex, and year of BMI record. Risk of first hospitalization was analyzed in the HFpEF sample with negative binomial and Cox proportional hazards models, adjusted for baseline comorbidities.

RESULTS

Compared with controls without HF matched on BMI, age, sex, and year of BMI record, patients with HFpEF displayed worse kidney function, greater estimated plasma volume, and more cardiovascular comorbidities. Within the HFpEF cohort, patients with higher degree of obesity were younger and had fewer concomitant cardiovascular comorbidities than those with lower degree of obesity. The mean number of HF-related hospitalizations increased with higher degree of obesity (9.6 to 15.7/100 patient-years; P=.002), but higher degree of obesity was not associated with increased risk of non-HF-related hospitalizations.

CONCLUSION

Among persons with obesity, increasing cardiorenal dysfunction and volume overload differentiate those with HFpEF. Among persons with established HFpEF, those with higher degree of obesity are younger and have fewer cardiovascular comorbidities but display a unique increased risk of HF-related hospitalizations, even as risk for other hospitalizations is not different.

Bio-Humoral and Non-Invasive Haemodynamic Correlates of Renal Venous Flow Patterns across the Heart Failure Spectrum

Background: We evaluated the bio-humoral and non-invasive haemodynamic correlates of renal congestion evaluated by Doppler renal venous flow (RVF) across the heart failure (HF) spectrum, from asymptomatic subjects with cardiovascular risk factors (Stage A) and structural heart disease (Stage B) to patients with clinically overt HF (Stage C). Methods: Ultrasound evaluation, including echocardiography, lung ultrasound and RVF, along with blood and urine sampling, was performed in 304 patients. Results: Continuous RVF was observed in 230 patients (76%), while discontinuous RVF (dRVF) was observed in 74 (24%): 39 patients had pulsatile RVF, 18 had biphasic RVF and 17 had monophasic RVF. Stage C HF was significantly more common among patients with dRVF. Monophasic RVF was associated with worse renal function and a higher urinary albumin-to-creatinine ratio (uACR). After adjusting for hypertension, diabetes mellitus, the presence of Stage C HF and serum creatinine levels, worsening RVF patterns were associated with higher NT-proBNP levels, worse right ventricular-arterial coupling, larger inferior vena cava and higher echo-derived pulmonary artery wedge pressure. This trend was confirmed when only patients with HF Stage C were analysed after adjusting for the left ventricle ejection fraction (LVEF). Conclusion: Abnormal RVF is common across the HF spectrum. Worsening RVF patterns are independently associated with increased congestion, worse non-invasive haemodynamics and impaired RV-arterial coupling. RVF evaluation could refine prognostic stratification across the HF spectrum, irrespective of LVEF.

Dynamic Mitral Regurgitation-An Easy to Miss Reversible Cause of Severe Pulmonary Vascular Remodeling

Respirophasic MR in HFrEF with severe pulmonary vascular disease and low output heart failure– Is there a role for treating the MR? @yreddyhf @BrendenIngraham @mayoclinicCV

Pericardial Immune Cells and Their Evolving Role in Cardiovascular Pathophysiology

The pericardium plays several homeostatic roles to support and maintain everyday cardiac function. Recent advances in techniques and experimental models have allowed for further exploration into the cellular contents of the pericardium itself. Of particular interest are the various immune cell populations present in the space within the pericardial fluid and fat. In contrast to immune cells of the comparable pleura, peritoneum and heart, pericardial immune cells appear to be distinct in their function and phenotype. Specifically, recent work has suggested these cells play critical roles in an array of pathophysiological conditions including myocardial infarction, pericarditis, and post-cardiac surgery complications. In this review, we spotlight the pericardial immune cells currently identified in mice and humans, the pathophysiological role of these cells, and the clinical significance of the immunocardiology axis in cardiovascular health.

Biventricular cardiac power reserve in heart failure with preserved ejection fraction

AIMS

Cardiac and extracardiac abnormalities play important roles in heart failure with preserved ejection fraction (HFpEF). Biventricular cardiac power output (BCPO) quantifies the total rate of hydraulic work performed by both ventricles, suggesting that it may help to identify patients with HFpEF and more severe cardiac impairments to better individualize treatment.

METHODS AND RESULTS

Patients with HFpEF (n = 398) underwent comprehensive echocardiography and invasive cardiopulmonary exercise testing. Patients were categorized as low BCPO reserve (n = 199, < median of 1.57 W) or preserved BCPO reserve (n = 199). As compared to those with preserved BCPO reserve, those with low reserve were older and leaner, with more atrial fibrillation, higher N-terminal pro-B-type natriuretic peptide levels, worse renal function, more impaired left ventricular (LV) global longitudinal strain, worse LV diastolic function and right ventricular longitudinal function. Cardiac filling pressures and pulmonary artery pressures at rest were higher in low BCPO reserve, but central pressures were similar during exercise to those with preserved BCPO reserve. Exertional systemic and pulmonary vascular resistances were higher and exercise capacity was more impaired in those with low BCPO reserve. Reduced BCPO reserve was associated with increased risk for the composite endpoint of heart failure hospitalization or death over 2.9 (interquartile range 0.9-4.5) years of follow-up (hazard ratio 2.77, 95% confidence interval 1.73-4.42, p < 0.0001).

CONCLUSIONS

Inability to enhance BCPO during exercise is associated with more advanced HFpEF, increased systemic and pulmonary vascular resistance, reduced exercise capacity and increased adverse events in patients with HFpEF. Novel therapies that enhance biventricular reserve merit further investigation for patients with this phenotype.

Heart failure and obesity: The latest pandemic

The marked rise in rates of obesity, which is most prominent among individuals from socio-economically disadvantaged circumstances, has been a powerful contributor to the rising prevalence of heart failure (HF). Obesity has indirect effects on HF through the development of several metabolic risk factors, but also direct adverse effects on the myocardium. Obesity contributes to myocardial dysfunction and HF risk through multiple mechanisms, including hemodynamic changes, neurohormonal activation, endocrine and paracrine effects of adipose tissue, ectopic fat deposition and lipotoxicity. These processes principally result in concentric left ventricular (LV) remodeling and predominant increase in the risk for HF with preserved LV ejection fraction (HFpEF). Despite the excess risk for HF associated with obesity, there is a well described obesity paradox in which individuals with overweight and grade I obesity have better survival than those with normal weight and overweight. Despite the obesity paradox among individuals with prevalent HF, intentional weight loss is associated with improvements in metabolic risk factors, myocardial dysfunction and quality of life, in a dose-response fashion. In matched observational studies of bariatric surgery patients, marked weight loss is associated with decreased risk for developing HF, as well as improved cardiovascular disease (CVD) outcomes in those with existing HF. Ongoing clinical trials using powerful new obesity pharmacotherapies in individuals in with obesity and CVD may provide definitive information regarding the cardiovascular impact of weight loss. Given the powerful contribution of rising obesity prevalence to rates of HF, addressing these intertwined epidemics is a clinical and public health priority.

Contemporary uses of inferior vena cava balloon occlusion

The evolution of the hybrid operative environment has expanded the utility of inferior vena cava balloon occlusion (IVCBO) in contemporary surgical practice. First described in the management of acute decompensated heart failure and venous thromboembolism, IVCBO has been utilised in deployment of thoracic endoprosthesis, repair of aorto-caval fistula, management of inferior vena cava (IVC) tumour thrombus and abdominal IVC trauma. More recently, IVCBO has also been utilised as a therapeutic strategy to assist patients with reduced ejection fraction and exercise tolerance in the form of an implantable device. Here we present a narrative review of the physiological impact of IVCBO as well as its historical, contemporary and future uses. The contemporary utilisation of IVCBO is a novel example of employing endovascular technology in the hybrid operative environment; paramount for the modern vascular surgeon who is now increasingly involved in multi-disciplinary management of complex clinical presentations.

Epicardial Fat in Heart Failure with Preserved Ejection Fraction: Bad Actor or Just Lying Around?

Heart failure with preserved ejection fraction (HFpEF) is increasingly recognised to be strongly associated with obesity and abnormalities in fat distribution. Epicardial fat has been associated with abnormal haemodynamics in HFpEF, with potential for direct mechanical effects on the heart causing constriction-like physiology and local myocardial remodelling effects from secretion of inflammatory and profibrotic mediators. However, patients with epicardial fat generally have more systemic and visceral adipose tissue making determination of causality between epicardial fat and HFpEF complex. In this review, we will summarise the evidence for epicardial fat being either directly causal in HFpEF pathogenesis or merely being a correlate of worse systemic inflammatory and generalised adiposity. We will also discuss therapies that directly target epicardial fat and may have potential for treating HFpEF and elucidating the independent role of epicardial fat in its pathogenesis.

Obesity and heart failure with preserved ejection fraction: new insights and pathophysiological targets

Obesity and heart failure with preserved ejection fraction (HFpEF) represent two intermingling epidemics driving perhaps the greatest unmet health problem in cardiovascular medicine in the 21st century. Many patients with HFpEF are either overweight or obese, and recent data have shown that increased body fat and its attendant metabolic sequelae have widespread, protean effects systemically and on the cardiovascular system leading to symptomatic HFpEF. The paucity of effective therapies in HFpEF underscores the importance of understanding the distinct pathophysiological mechanisms of obese HFpEF to develop novel therapies. In this review, we summarize the current understanding of the cardiovascular and non-cardiovascular features of the obese phenotype of HFpEF, how increased adiposity might pathophysiologically contribute to the phenotype, and how these processes might be targeted therapeutically.

Inflammatory pathways in heart failure with preserved left ventricular ejection fraction: implications for future interventions

Many patients with symptoms and signs of heart failure have a left ventricular ejection fraction ≥50%, termed heart failure with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous syndrome mainly affecting older people who have many other cardiac and non-cardiac conditions that often cast doubt on the origin of symptoms, such as breathlessness, or signs, such as peripheral oedema, rendering them neither sensitive nor specific to the diagnosis of HFpEF. Currently, management of HFpEF is mainly directed at controlling symptoms and treating comorbid conditions such as hypertension, atrial fibrillation, anaemia, and coronary artery disease. HFpEF is also characterized by a persistent increase in inflammatory biomarkers. Inflammation may be a key driver of the development and progression of HFpEF and many of its associated comorbidities. Detailed characterization of specific inflammatory pathways may provide insights into the pathophysiology of HFpEF and guide its future management. There is growing interest in novel therapies specifically designed to target deregulated inflammation in many therapeutic areas, including cardiovascular disease. However, large-scale clinical trials investigating the effectiveness of anti-inflammatory treatments in HFpEF are still lacking. In this manuscript, we review the role of inflammation in HFpEF and the possible implications for future trials.

Cardiopulmonary exercise testing for heart failure: pathophysiology and predictive markers

Despite the numerous recent advancements in therapy, heart failure (HF) remains a principle cause of both morbidity and mortality. HF with preserved ejection fraction (HFpEF), a condition that shares the prevalence and adverse outcomes of HF with reduced ejection fraction, remains poorly recognised in its initial manifestations. Cardiopulmonary exercise testing (CPET), defined as a progressive work exercise test that includes non-invasive continuous measurement of cardiovascular and respiratory parameters, provides a reliable mode to evaluate for early features and for the assessment of prognostic features of both forms of HF. While CPET measurements are standard of care for advanced HF and transplant programmes, they merit a broader clinical application in the early diagnosis and assessment of patients with HFpEF. In this review, we provide an overview of the pathophysiology of exercise intolerance in HF and discuss key findings in CPETs used to evaluate both severity of impairment and the prognostic implications.

Changes in epicardial and visceral adipose tissue depots following bariatric surgery and their effect on cardiac geometry

Introduction

Obesity affects cardiac geometry, causing both eccentric (due to increased cardiac output) and concentric (due to insulin resistance) remodelling. Following bariatric surgery, reversal of both processes should occur. Furthermore, epicardial adipose tissue loss following bariatric surgery may reduce pericardial restraint, allowing further chamber expansion. We investigated these changes in a serial imaging study of adipose depots and cardiac geometry following bariatric surgery.

Methods

62 patients underwent cardiac magnetic resonance (CMR) before and after bariatric surgery, including 36 with short-term (median 212 days), 37 medium-term (median 428 days) and 32 long-term (median 1030 days) follow-up. CMR was used to assess cardiac geometry (left atrial volume (LAV) and left ventricular end-diastolic volume (LVEDV)), LV mass (LVM) and LV eccentricity index (LVei - a marker of pericardial restraint). Abdominal visceral (VAT) and epicardial (EAT) adipose tissue were also measured.

Results

Patients on average had lost 21kg (38.9% excess weight loss, EWL) at 212 days and 36kg (64.7% EWL) at 1030 days following bariatric surgery. Most VAT and EAT loss (43% and 14%, p<0.0001) occurred within the first 212 days, with non-significant reductions thereafter. In the short-term LVM (7.4%), LVEDV (8.6%) and LAV (13%) all decreased (all p<0.0001), with change in cardiac output correlated with LVEDV (r=0.35,p=0.03) and LAV change (r=0.37,p=0.03). Whereas LVM continued to decrease with time (12% decrease relative to baseline at 1030 days, p<0.0001), both LAV and LVEDV had returned to baseline by 1030 days. LV mass:volume ratio (a marker of concentric hypertrophy) reached its nadir at the longest timepoint (p<0.001). At baseline, LVei correlated with baseline EAT (r=0.37,p=0.0040), and decreased significantly from 1.09 at baseline to a low of 1.04 at 428 days (p<0.0001). Furthermore, change in EAT following bariatric surgery correlated with change in LVei (r=0.43,p=0.0007).

Conclusions

Cardiac volumes show a biphasic response to weight loss, initially becoming smaller and then returning to pre-operative sizes by 1030 days. We propose this is due to an initial reversal of eccentric remodelling followed by reversal of concentric remodelling. Furthermore, we provide evidence for a role of EAT contributing to pericardial restraint, with EAT loss improving markers of pericardial restraint.

Echocardiographic diagnosis of heart failure with preserved ejection fraction in elderly patients with hypertension

Objectives. The aim of this study is to evaluate the diagnostic performance of echocardiography for the diagnosis of heart failure with preserved ejection fraction (HFpEF) in the elderly and to validate the Heart Failure Association diagnostic algorithm (HFA-PEFF). Design. A case-control study was conducted in patients with hypertension with or without HFpEF who were matched for age (n = 33; 78.4 ± 5.3 years) and sex. Participants underwent echocardiography including assessment of left atrial (LA) volume index (LAVI), early mitral filling to early diastolic mitral annulus velocity ratio (E/e'), LA reservoir strain (LASr), tissue Doppler LA contraction (a'), right ventricular isovolumic relaxation time (RVIVRT), and a 6-minute walk test (6-MWT). The filling pressure algorithm from the European association of cardiovascular imaging (EACVI) 2021 was applied. The HFA-PEFF score was also applied, using echocardiography parameters and the value of NT pro-BNP, without considering symptomatic status. Results. Echocardiographic parameters identified patients with HFpEF with an area under the curve (AUC) >0.9 for E/e', RVIVRT, LASr, a', and the ratio of LAVI/a'. LASr correlated with 6-MWT (r = 0.59, p = .0003). The EACVI algorithm classified all controls with normal filling pressure and 94% of patients with HFpEF with increased filling pressure. When the HFA-PEFF diagnostic algorithm was validated, a high score (≥5 points) had 100% sensitivity for HFpEF, while 88% of controls had intermediate scores (2-4 points). Conclusion. The EACVI filling pressure algorithm, RVIVRT, LASr, and the ratio LAVI/a' were accurate for diagnosing HFpEF in elderly patients with hypertension. The HFA-PEFF score had high sensitivity but limited ability to exclude HFpEF.

Dynamic aspects of ventricular interaction during exercise in HFpEF and in pre-capillary pulmonary hypertension

AIMS

The contribution of adverse ventricular interdependence remains undervalued in heart failure or pulmonary vascular disease, and not much is known about its dynamic nature during exercise and respiration. In this study, we evaluated ventricular interaction during exercise in patients with heart failure with preserved ejection fraction (HFpEF) and patients with chronic thromboembolic pulmonary hypertension (CTEPH) as compared with healthy controls.

METHODS AND RESULTS

Forty-six subjects (10 controls, 19 CTEPH patients, and 17 HFpEF patients) underwent cardiac magnetic resonance imaging during exercise. Ventricular interaction was determined through analysis of the septal curvature (SC) of a mid-ventricular short-axis slice at end-diastole, end-systole, and early-diastole, both in expiration and inspiration. Exercise amplified ventricular interaction in CTEPH patients and to a lesser extent in HFpEF patients (P < 0.05 for decrease in SC with exercise). Adverse interaction was most profound in early-diastole and most pronounced in CTEPH patients (P < 0.05 interaction group * exercise) because of a disproportionate increase RV afterload (P < 0.05 to both controls and HFpEF) and diastolic pericardial restraint (P < 0.001 for interaction group * exercise) during exercise. Inspiration enhanced diastolic interdependence in CTEPH and HFpEF patients (P < 0.05 vs. expiration). Both at rest and during exercise, SC strongly correlated with RV volumes and pulmonary artery pressures (all P < 0.05).

CONCLUSIONS

Exercise amplifies adverse right-left ventricular interactions in CTEPH, while a more moderate effect is observed in isolated post-capillary HFpEF. Given the strong link with RV function and pulmonary hemodynamic, assessing ventricular interaction with exCMR might be valuable from a diagnostic or therapeutic perspective.

Hemodynamic Assessment in Heart Failure with Preserved Ejection Fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) is characterized by an inability of the heart to perfuse the body without pathologic increases in filling pressure at rest or during exertion. Right heart catheterization provides direct assessment for HF, providing the most robust and direct method to evaluate the central hemodynamic abnormalities, and serves as the gold standard to confirm or refute the presence of HFpEF. This article reviews current understanding of the best practices in the performance and interpretation of hemodynamic assessment, relates important pathophysiologic concepts to clinical care, and discusses current and evidence-based applications of hemodynamics in HFpEF.

Right-Sided Mechanical Circulatory Support - A Hemodynamic Perspective

PURPOSE OF REVIEW

Right ventricular (RV) failure is increasingly recognized as a major cause of morbidity and mortality. When RV failure is refractory to medical therapy, escalation to right-sided mechanical circulatory support (MCS) should be considered. In this review, we begin by recapitulating the hemodynamics of RV failure, then we delve into current and future right-sided MCS devices and describe their hemodynamic profiles.

RECENT FINDINGS

The field of temporary right-sided MCS continues to expand, with evolving strategies and new devices actively under development. All right-sided MCS devices bypass the RV, with each bypass configuration conferring a unique hemodynamic profile. Devices that aspirate blood directly from the RV, as opposed to the RA or the IVC, have more favorable hemodynamics and more effective RV unloading. There has been a growing interest in single-access MCS devices which do not restrict patient mobility. Additionally, a first-of-its-kind percutaneous, pulsatile, right-sided MCS device (PERKAT RV) is currently undergoing investigation in humans. Prompt recognition of refractory RV failure and deployment of right-sided MCS can improve outcomes. The field of right-sided MCS is rapidly evolving, with ongoing efforts dedicated towards developing novel temporary devices that are single access, allow for patient mobility, and directly unload the RV, as well as more durable devices.

Pulmonary vascular disease in pulmonary hypertension due to left heart disease: pathophysiologic implications

AIMS

Pulmonary hypertension (PH) and pulmonary vascular disease (PVD) are common and associated with adverse outcomes in left heart disease (LHD). This study sought to characterize the pathophysiology of PVD across the spectrum of PH in LHD.

METHODS AND RESULTS

Patients with PH-LHD [mean pulmonary artery (PA) pressure >20 mmHg and PA wedge pressure (PAWP) ≥15 mmHg] and controls free of PH or LHD underwent invasive haemodynamic exercise testing with simultaneous echocardiography, expired air and blood gas analysis, and lung ultrasound in a prospective study. Patients with PH-LHD were divided into isolated post-capillary PH (IpcPH) and PVD [combined post- and pre-capillary PH (CpcPH)] based upon pulmonary vascular resistance (PVR <3.0 or ≥3.0 WU). As compared with controls (n = 69) and IpcPH-LHD (n = 55), participants with CpcPH-LHD (n = 40) displayed poorer left atrial function and more severe right ventricular (RV) dysfunction at rest. With exercise, patients with CpcPH-LHD displayed similar PAWP to IpcPH-LHD, but more severe RV-PA uncoupling, greater ventricular interaction, and more severe impairments in cardiac output, O2 delivery, and peak O2 consumption. Despite higher PVR, participants with CpcPH developed more severe lung congestion compared with both IpcPH-LHD and controls, which was associated lower arterial O2 tension, reduced alveolar ventilation, decreased pulmonary O2 diffusion, and greater ventilation-perfusion mismatch.

CONCLUSIONS

Pulmonary vascular disease in LHD is associated with a distinct pathophysiologic signature marked by greater exercise-induced lung congestion, arterial hypoxaemia, RV-PA uncoupling, ventricular interdependence, and impairment in O2 delivery, impairing aerobic capacity. Further study is required to identify novel treatments targeting the pulmonary vasculature in PH-LHD.

The Interventricular Septum: Structure, Function, Dysfunction, and Diseases

Vertebrates developed pulmonary circulation and septated the heart into venous and arterial compartments, as the adaptation from aquatic to terrestrial life requires more oxygen and energy. The interventricular septum (IVS) accommodates the ventricular portion of the conduction system and contributes to the mechanical function of both ventricles. Conditions or diseases that affect IVS structure and function (e.g., hypertrophy, defects, other) may lead to ventricular pump failure and/or ventricular arrhythmias with grave consequences. IVS structure and function can be evaluated today using current imaging techniques. Effective therapies can be provided in most cases, although definitions of underlying etiologies may not always be easy, particularly in the elderly due to overlap between genetic and acquired causes of IVS hypertrophy, the most common being IVS abnormality. In this review, state-of-the-art information regarding IVS morphology, physiology, physiopathology, and disease is presented.

Unloading the right to fill the left: vasodilation to treat hypotension: a case report

Background

Management of pulmonary hypertension (PH) in the setting of heart failure with preserved ejection fraction (HFpEF) can be challenging. Herein, we describe the case of a patient with HFpEF and combined pre- and post-capillary PH who showed striking improvement with sildenafil.

Case summary

A 74-year-old man presented with exertional dyspnea and near-syncope. He underwent a hemodynamic exercise study that showed evidence of HFpEF with pre- and post-capillary PH. Right ventricular endomyocardial biopsy showed interstitial fibrosis and mild hypertrophy, with no evidence of infiltrative or storage diseases. The patient was treated with sildenafil 20 mg three times daily, which resulted in significant symptomatic and functional improvement in 12 years of follow-up.

Discussion

Phosphodiesterase 5 inhibitors are currently not approved by the United States Food and Drug Administration for treatment of PH in heart failure and are used off-label in patients with heart failure. This case illustrates the importance of unloading the right ventricle to improve cardiac output in patients with diastolic dysfunction and combined pre- and post-capillary PH. Although promising, future studies are needed to validate these findings.

Pulmonary Vasculature Responsiveness to Phosphodiesterase-5A Inhibition in Heart Failure With Reduced Ejection Fraction: Possible Role of Plasma Potassium

Introduction

Phosphodiesterase-5a inhibition (PDE5i) leads to favorable changes in pulmonary hemodynamic and cardiac output (CO) in patients with advanced heart failure (HF) and reduced ejection fraction (HFrEF). The hemodynamic response to PDE5i could be heterogeneous and the clinical variables associated with these changes are scarcely investigated.

Materials and Methods

Of 260 patients with advanced HFrEF referred for advanced therapies [cardiac transplant/left ventricular assist device (LVAD)], 55 had pulmonary hypertension (PH) and fulfilled the criteria for the PDE5i vasoreactivity test. Right heart catheterization (RHC) was performed as a part of clinical evaluation before and after 20-mg intravenous sildenafil. Absolute and relative changes in pulmonary vascular resistance (PVR) were evaluated to assess hemodynamic response to PDE5i. Clinical, biochemical, and hemodynamic factors associated with PVR changes were identified.

Results

Sildenafil administration reduced PVR (− 45.3%) and transpulmonary gradient (TPG; − 34.8%) and increased CO (+ 13.6%). Relative change analysis showed a negative moderate association between baseline plasma potassium and changes in PVR (r = − 0.48; p = 0.001) and TPG (r = − 0.43; p = 0.005) after PDE5i. Aldosterone concentration shows a direct moderate association with PVR changes after PDE5i. A significant moderate association was also demonstrated between CO improvement and the severity of mitral (r = 0.42; p = 0.002) and tricuspid (r = 0.39; p = 0.004) regurgitation.

Conclusion

We identified plasma potassium, plasma aldosterone level, and atrioventricular valve regurgitations as potential cofounders of hemodynamic response to acute administration of PDE5i. Whether modulation of potassium levels could enhance pulmonary vasoreactivity in advanced HFrEF deserves further research.

Synchronized diaphragmatic stimulation for heart failure using the VisONE system: a first-in-patient study

Aims

Synchronized diaphragmatic stimulation (SDS) modulates intrathoracic and intra‐abdominal pressures with favourable effects on cardiac function for patients with a reduced left ventricular ejection fraction (LVEF) and heart failure (HFrEF). VisONE‐HF is a first‐in‐patient, observational study assessing the feasibility and 1 year effects of a novel, minimally invasive SDS device.

Methods and results

The SDS system comprises a pulse generator and two laparoscopically delivered, bipolar, active‐fixation leads on the inferior diaphragmatic surface. Fifteen symptomatic men with HFrEF and ischaemic heart disease receiving guideline‐recommended therapy were enrolled (age 60 [56, 67] years, New York Heart Association class II [53%] /III [47%], LVEF 27 [23, 33] %, QRSd 117 [100, 125] ms, & N terminal pro brain natriuretic peptide [NT‐proBNP] 1779 [911, 2,072] pg/mL). Implant success was 100%. Patients were evaluated at 3, 6, and 12 months for device‐related or lead‐related complications, quality of life (SF‐36 QOL), 6 min hall walk distance (6MHWd), and by echocardiography. No implant procedure or SDS‐related adverse event occurred, and patients were unaware of diaphragmatic stimulation. By 12 months, left ventricular end‐systolic volume decreased (136 [123, 170] mL to 98 [89, 106] mL; P = 0.05), 6MHWd increased (315 [300, 330] m to 340 [315, 368] m; P = 0.004), and SF‐36 QOL improved (physical scale 0 [0, 0] to 25 [0, 50], P = 0.006; emotional scale 0 [0, 33] to 33 [33, 67], P = 0.001). Although neither reached statistical significance, LVEF decreased (28 [23, 40]% vs. 34 [29, 38]%; P = ns) and NT‐proBNP was lower (1784 [920, 2540] pg/mL vs. 1492 [879, 2028] pg/mL; P = ns).

Conclusions

These data demonstrate the feasibility of laparoscopic implantation and delivery of SDS without raising safety concerns. These encouraging findings should be investigated further in adequately powered randomized trials.

Heart failure with preserved ejection fraction in patients with normal natriuretic peptide levels is associated with increased morbidity and mortality

BACKGROUND

A substantial proportion of patients with heart failure (HF) with preserved ejection fraction (HFpEF) present with normal natriuretic peptide (NP) levels. The pathophysiology and natural history for this phenotype remain unclear.

METHODS AND RESULTS

Consecutive subjects undergoing invasive cardiopulmonary exercise testing for unexplained dyspnoea at Mayo Clinic in 2006-18 were studied. Heart failure with preserved ejection fraction was defined as a pulmonary arterial wedge pressure (PAWP) ≥15 mmHg (rest) or ≥25 mmHg (exercise). Patients with HFpEF and normal NP [N-terminal of the pro-hormone B-type natriuretic peptide (NT-proBNP) < 125 ng/L] were compared with HFpEF with high NP (NT-proBNP ≥ 125 ng/L) and controls with normal haemodynamics. Patients with HFpEF and normal (n = 157) vs. high NP (n = 263) were younger, yet older than controls (n = 161), with an intermediate comorbidity profile. Normal NP HFpEF was associated with more left ventricular hypertrophy and worse diastolic function compared with controls, but better diastolic function, lower left atrial volumes, superior right ventricular function, and less mitral/tricuspid regurgitation compared with high NP HFpEF. Cardiac output (CO) reserve with exercise was preserved in normal NP HFpEF [101% predicted, interquartile range (IQR): 75-124%], but this was achieved only at the cost of higher left ventricular transmural pressure (LVTMP) (14 ± 6 mmHg vs. 7 ± 4 mmHg in controls, P < 0.001). In contrast, CO reserve was decreased in high NP HFpEF (85% predicted, IQR: 59-109%), with lower LVTMP (10 ± 8 mmHg) compared with normal NP HFpEF (P < 0.001), despite similar PAWP. Patients with high NP HFpEF displayed the highest event rates, but normal NP HFpEF still had 2.7-fold higher risk for mortality or HF readmissions compared with controls (hazard ratio: 2.74, 95% confidence interval: 1.02-7.32) after adjusting for age, sex, and body mass index.

CONCLUSION

Patients with HFpEF and normal NP display mild diastolic dysfunction and preserved CO reserve during exercise, despite marked elevation in filling pressures. While clinical outcomes are not as poor compared with patients with high NP, patients with normal NP HFpEF exhibit increased risk of death or HF readmissions compared with patients without HF, emphasizing the importance of this phenotype.

Therapeutic augmentation of NO-sGC-cGMP signalling: lessons learned from pulmonary arterial hypertension and heart failure

The nitric oxide (NO)-guanylate cyclase (GC)-cyclic guanosine monophosphate (cGMP) pathway plays an important role in cardiovascular, pulmonary and renal function. Phosphodiesterase-5 inhibitors (PDE-5i) inhibit cGMP degradation, whereas both soluble guanylate cyclase (sGC) stimulators and sGC activators directly increase sGC. PDE-5i (e.g. sildenafil, tadalafil) and sGC stimulators (e.g. riociguat, vericiguat) have been extensively used in pulmonary artery hypertension (PAH) and heart failure (HF). PDE-5i have also been used in end-stage HF before and after left ventricular (LV) assist device (LVAD) implantation. Augmentation of NO-GC-cGMP signalling with PDE-5i causes selective pulmonary vasodilation, which is highly effective in PAH but may have controversial, potentially adverse effects in HF, including pre-LVAD implant due to device unmasking of PDE-5i-induced RV dysfunction. In contrast, retrospective analyses have demonstrated that PDE-5i have beneficial effects when initiated post LVAD implant due to the improved haemodynamics of the supported LV and the pleiotropic actions of these compounds. sGC stimulators, in turn, are effective both in PAH and in HF due to their balanced pulmonary and systemic vasodilation, and as such they are preferable to PDE-5i if the use of a pulmonary vasodilator is needed in HF patients, including those listed for LVAD implantation. Regarding the effectiveness of PDE-5i and sGC stimulators when initiated post LVAD implant, these two groups of compounds should be tested in a randomized control trial.

The Value of Passive Leg Raise During Right Heart Catheterization in Diagnosing Heart Failure With Preserved Ejection Fraction

BACKGROUND

Because of limited accuracy of noninvasive tests, diastolic stress testing plays an important role in the diagnostic work-up of patients with heart failure with preserved ejection fraction (HFpEF). Exercise right heart catheterization is considered the gold standard and indicated when HFpEF is suspected but left ventricular filling pressures at rest are normal. However, performing exercise during right heart catheterization is not universally available. Here, we examined whether pulmonary capillary wedge pressure (PCWP) during a passive leg raise (PLR) could be used as simple and accurate method to diagnose or rule out occult-HFpEF.

METHODS

In our tertiary center for pulmonary hypertension and HFpEF, all patients who received a diagnostic right heart catheterization with PCWP-measurements at rest, PLR, and exercise were evaluated (2014-2020). The diagnostic value of PCWP_PLR was compared with the gold standard (PCWP_EXERCISE). Cut-offs derived from our cohort were subsequently validated in an external cohort (N=74).

RESULTS

Thirty-nine non-HFpEF, 33 occult-HFpEF, and 37 manifest-HFpEF patients were included (N=109). In patients with normal PCWP_REST (<15 mmHg), PCWP_PLR significantly improved diagnostic accuracy compared with PCWP_REST (AUC=0.82 versus 0.69, P=0.03). PCWP_PLR ≥19 mmHg (24% of cases) had a specificity of 100% for diagnosing occult-HFpEF, irrespective of diuretic use. PCWP_PLR ≥11 mmHg had a 100% sensitivity and negative predictive value for diagnosing occult-HFpEF. Both cut-offs retained a 100% specificity and 100% sensitivity in the external cohort. Absolute change in PCWP_PLR or V-wave derived parameters had no incremental value in diagnosing occult-HFpEF.

CONCLUSIONS

PCWP_PLR is a simple and powerful tool that can help to diagnose or rule out occult-HFpEF.

Synchronized diaphragmatic stimulation: a case report of a novel extra-cardiac intervention for chronic heart failure

Synchronized diaphragmatic stimulation (SDS) is a novel extra‐cardiac device‐based therapy for symptomatic heart failure with reduced ejection fraction. SDS provides imperceptible chronic stimulation of the diaphragm through a laparoscopically implanted system consisting of an implantable pulse generator and two sensing/stimulating leads affixed to the inferior surface of the diaphragm delivering imperceptible R‐wave gaited pulses that alter intrathoracic pressure improving ventricular filling and cardiac output. We describe, in a man with a history of myocardial infarctions resulting in heart failure and persistent New York Heart Association Class III symptoms despite standard therapies, the successful implantation of SDS resulting in improved quality of life, N‐terminal pro brain natriuretic peptide, cardiac function, and exercise tolerance through 12 months of follow‐up. Randomized trials are now required to validate these findings.

Exercise-induced pulmonary hypertension in HFpEF and HFrEF: Different pathophysiologic mechanism behind similar functional impairment

AIMS

Pathophysiological mechanisms behind cardio-pulmonary impairment in heart failure (HF) with reduced (HFrEF) and preserved (HFpEF) ejection fraction are likely different. We analysed them using combined cardiopulmonary-exercise stress echocardiography (CPET-ESE).

METHODS

We matched 1:1 subjects with HFrEF (n = 90) and HFpEF (n = 90) for age, sex, body mass index (BMI), peak oxygen consumption, and minute ventilation/carbon dioxide production slope. All patients underwent a symptom-limited graded ramp bicycle CPET-ESE compared with 40 age-, sex- and BMI-matched healthy controls.

RESULTS

During a median follow-up of 25 months, we observed 22 deaths and 80 HF hospitalisations, with similar distribution between HFpEF and HFrEF. Compared with HFrEF, HFpEF had a higher prevalence of metabolic syndrome (p = 0.02) with higher levels of high-sensitivity C-reactive protein and uric acid (p < 0.01). The multipoint mean pulmonary artery pressure/cardiac output (mPAP/CO) slope showed equally increased values in HFrEF and HFpEF (3.5 ± 1.8 and 3.7 ± 1.5 mmHg/L/min) compared with controls (1.8 ± 1.1 mmHg/L/min; p < 0.0001). During exercise, HFpEF displayed more adverse interaction of right ventricle-pulmonary artery (RV-PA; tricuspid annular plane systolic excursion/systolic pulmonary artery pressure: 0.40 ± 0.2 vs 0.47 ± 0.2 mm/mmHg in HFrEF; p < 0.01) and left atrium-left ventricle (LA-LV; LA reservoir strain/LV global longitudinal strain: 1.5 ± 0.8 vs 2.2 ± 1.1 in HFrEF; p < 0.01). The latter were independent predictors of mPAP/CO slope, along with hs-CRP (adjusted R2: 0.21; p < 0.0001).

CONCLUSION

Despite similar disease severity, HFpEF and HFrEF show different pathophysiological mechanisms. HFpEF is characterised by a worse LA-LV and RV-PA interaction than HFrEF, with more prevalent low-grade systemic inflammation. In HFpEF, these features may have a role in exercise-induced pulmonary hypertension.

Characterization of Cardiac Sympathetic Nervous System and Inflammatory Activation in HFpEF Patients

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Although there is evidence for activation of the sympathetic nervous system and inflammatory pathways in peripheral blood samples, their relationship to myocardial activity is unknown.

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Using arterial and coronary sinus blood sampling, we have shown the presence of cardiac and systemic sympathetic activation in HFpEF patients. However although systemic inflammatory activation was readily apparent, there was detectable myocardial release of inflammatory cytokines.

•

Key hemodynamic and demographic factors that typically cluster together in HFpEF appeared to drive cardiac sympathetic activation.

•

The data suggest that there may be a role for antiadrenergic therapies in selected HFpEF patients.

We have shown that systemic and cardiac sympathetic activation is present in heart failure with preserved ejection fraction (HFpEF) patients. Conversely, whereas systemic inflammatory activation was also detected in HFpEF, we did not detect local myocardial release of inflammatory cytokines. Activation of the sympathetic system correlated with both hemodynamic and demographic factors that characteristically cluster together in HFpEF. Together these data suggest that there may be a role for antiadrenergic therapies in certain HFpEF patients. The study does not implicate locally derived cytokines in the myocardial biology of HFpEF, although systemic sources may contribute to the global pathophysiology of HFpEF.

Heart Failure with Preserved Ejection Fraction: Mechanisms and Treatment Strategies

Approximately half of all patients with heart failure (HF) have a preserved ejection fraction, and the prevalence is growing rapidly given the aging population in many countries and the rising prevalence of obesity, diabetes, and hypertension. Functional capacity and quality of life are severely impaired in heart failure with preserved ejection fraction (HFpEF), and morbidity and mortality are high. In striking contrast to HF with reduced ejection fraction, there are few effective treatments currently identified for HFpEF, and these are limited to decongestion by diuretics, promotion of a healthy active lifestyle, and management of comorbidities. Improved phenotyping of subgroups within the overall HFpEF population might enhance individualization of treatment. This review focuses on the current understanding of the pathophysiologic mechanisms underlying HFpEF and treatment strategies for this complex syndrome.

Intermittent Occlusion of the Superior Vena Cava to Improve Hemodynamics in Patients With Acutely Decompensated Heart Failure: The VENUS-HF Early Feasibility Study

BACKGROUND

Reducing congestion remains a primary target of therapy for acutely decompensated heart failure. The VENUS-HF EFS (VENUS-Heart Failure Early Feasibility Study) is the first clinical trial testing intermittent occlusion of the superior vena cava with the preCARDIA system, a catheter mounted balloon and pump console, to improve decongestion in acutely decompensated heart failure.

METHODS

In a multicenter, prospective, single-arm exploratory safety and feasibility trial, 30 patients with acutely decompensated heart failure were assigned to preCARDIA therapy for 12 or 24 hours. The primary safety outcome was a composite of major adverse cardiovascular and cerebrovascular events through 30 days. Secondary end points included technical success defined as successful preCARDIA placement, treatment, and removal and reduction in right atrial and pulmonary capillary wedge pressure. Other efficacy measures included urine output and patient-reported symptoms.

RESULTS

Thirty patients were enrolled and assigned to receive the preCARDIA system. Freedom from device- or procedure-related major adverse events was observed in 100% (n=30/30) of patients. The system was successfully placed, activated and removed after 12 (n=6) or 24 hours (n=23) in 97% (n=29/30) of patients. Compared with baseline values, right atrial pressure decreased by 34% (17±4 versus 11±5 mm Hg, P<0.001) and pulmonary capillary wedge pressure decreased by 27% (31±8 versus 22±9 mm Hg, P<0.001). Compared with pretreatment values, urine output and net fluid balance increased by 130% and 156%, respectively, with up to 24 hours of treatment (P<0.01).

CONCLUSIONS

We report the first-in-human experience of intermittent superior vena cava occlusion using the preCARDIA system to reduce congestion in acutely decompensated heart failure. PreCARDIA treatment for up to 24 hours was well tolerated without device- or procedure-related serious or major adverse events and associated with reduced filling pressures and increased urine output. These results support future studies characterizing the clinical utility of the preCARDIA system.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03836079.

Hemodynamics for the Heart Failure Clinician: A State-of-the-Art Review

Heart failure (HF) fundamentally reflects an inability of the heart to provide adequate blood flow to the body without incurring the cost of increased cardiac filling pressures. This failure occurs first during the stressed state, but progresses until hemodynamic derangements become apparent at rest. As such, the measurement and interpretation of both resting and stressed hemodynamics serve an integral role in the practice of the HF clinician. In this review, we discuss conceptual and technical best practices in the performance and interpretation of both resting and invasive exercise hemodynamic catheterization, relate important pathophysiologic concepts to clinical care, and discuss updated, evidence-based applications of hemodynamics as they pertain to the full spectrum of HF conditions.