Burkhoff, Daniel

Aims In heart failure (HF) with preserved ejection fraction (HFpEF), excessive redistribution of blood volume into the central circulation leads to elevations of intracardiac pressures with exercise limitations. Splanchnic ablation for volume management (SAVM) has been proposed as a therapeutic intervention. Here we present preliminary safety and efficacy data from the initial roll‐in cohort of the REBALANCE‐HF trial. Methods and results The open‐label (roll‐in) arm of REBALANCE‐HF will enrol up to 30 patients, followed by the randomized, sham‐controlled portion of the trial (up to 80 additional patients). Patients with HF, left ventricular ejection fraction (LVEF) ≥50%, and invasive peak exercise pulmonary capillary wedge pressure (PCWP) ≥25 mmHg underwent SAVM. Baseline and follow‐up assessments included resting and exercise PCWP, New York Heart Association (NYHA) class, Kansas City Cardiomyopathy Questionnaire (KCCQ), 6‐min walk test, and N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP). Efficacy and safety were assessed at 1 and 3 months. Here we report on the first 18 patients with HFpEF that have been enrolled into the roll‐in, open‐label arm of the study across nine centres; 14 (78%) female; 16 (89%) in NYHA class III; and median (interquartile range) age 75.2 (68.4–81) years, LVEF 61.0 (56.0–63.2)%, and average (standard deviation) 20 W exercise PCWP 36.4 (±8.6) mmHg. All 18 patients were successfully treated. Three non‐serious moderate device/procedure‐related adverse events were reported. At 1‐month, the mean PCWP at 20 W exercise decreased from 36.4 (±8.6) to 28.9 (±7.8) mmHg ( p < 0.01), NYHA class improved by at least one class in 33% of patients ( p = 0.02) and KCCQ score improved by 22.1 points (95% confidence interval 9.4–34.2) ( p < 0.01). Conclusion The preliminary open‐label results from the multicentre REBALANCE‐HF roll‐in cohort support the safety and efficacy of SAVM in HFpEF. The findings require confirmation in the ongoing randomized, sham‐controlled portion of the trial.

Background: In REDUCE LAP-HF II (A Study to Evaluate the Corvia Medical, Inc IASD System II to Reduce Elevated Left Atrial Pressure in Patients With Heart Failure), implantation of an atrial shunt device did not provide overall clinical benefit for patients with heart failure with preserved or mildly reduced ejection fraction. However, prespecified analyses identified differences in response in subgroups defined by pulmonary artery systolic pressure during submaximal exercise, right atrial volume, and sex. Shunt implantation reduces left atrial pressures but increases pulmonary blood flow, which may be poorly tolerated in patients with pulmonary vascular disease (PVD). On the basis of these results, we hypothesized that patients with latent PVD, defined as elevated pulmonary vascular resistance during exercise, might be harmed by shunt implantation, and conversely that patients without PVD might benefit. Methods: REDUCE LAP-HF II enrolled 626 patients with heart failure, ejection fraction ≥40%, exercise pulmonary capillary wedge pressure ≥25 mm Hg, and resting pulmonary vascular resistance <3.5 Wood units who were randomized 1:1 to atrial shunt device or sham control. The primary outcome—a hierarchical composite of cardiovascular death, nonfatal ischemic stroke, recurrent HF events, and change in health status—was analyzed using the win ratio. Latent PVD was defined as pulmonary vascular resistance ≥1.74 Wood units (highest tertile) at peak exercise, measured before randomization. Results: Compared with patients without PVD (n=382), those with latent PVD (n=188) were older, had more atrial fibrillation and right heart dysfunction, and were more likely to have elevated left atrial pressure at rest. Shunt treatment was associated with worse outcomes in patients with PVD (win ratio, 0.60 [95% CI, 0.42, 0.86]; P =0.005) and signal of clinical benefit in patients without PVD (win ratio, 1.31 [95% CI, 1.02, 1.68]; P =0.038). Patients with larger right atrial volumes and men had worse outcomes with the device and both groups were more likely to have pacemakers, heart failure with mildly reduced ejection fraction, and increased left atrial volume. For patients without latent PVD or pacemaker (n=313; 50% of randomized patients), shunt treatment resulted in more robust signal of clinical benefit (win ratio, 1.51 [95% CI, 1.14, 2.00]; P =0.004). Conclusions: In patients with heart failure with preserved or mildly reduced ejection fraction, the presence of latent PVD uncovered by invasive hemodynamic exercise testing identifies patients who may worsen with atrial shunt therapy, whereas those without latent PVD may benefit.

Background: The relationship between blood volume and pressure in the vascular system can be described in terms of unstressed and stressed blood volume. Stressed blood volume determines venous pressure and provides preload back to the heart, which regulates the generation of cardiac output (CO) via the Frank-starling mechanism. Whether sodium-glucose cotransporter-2 (SGLT2i) favorably modifies stressed blood volume is not known. Hypothesis: To investigate the effect of SGLT2i (empagliflozin) on the hemodynamic estimated stressed blood volume (eSBV) in HFrEF patients compared to placebo. Methods: A post hoc analysis of investigator-initiated, double-blinded, placebo-controlled, randomized trial. Seventy patients were assigned to empagliflozin of 10 mg or matching placebo once daily for 12 weeks. Patients underwent right heart catheterization at rest and during exercise at baseline and follow-up. Outcome was change in eSBV after 12 weeks of empagliflozin treatment at each level of exercise. We conducted computer-modelling simulations based on invasive hemodynamic assessment to measure eSBV. Results: HFrEF patients with mean age was 57 years, mean ejection fraction 27%, 47 (71%) on diuretics were randomized. After 12 weeks treatment exercise eSBV was significantly reduced at 0 watt, 25 watt and 25 % of maximal exercise watt, compared to placebo [(0 watt; –258 mL, 95% CI –476 to –39, p=0.021); (25 watt; –301 mL, 95% CI –561 to –40, p=0.024); and (25% of peak exercise watt; –262 mL, 95% CI –490 to –34, p=0.024)]. There was no effect on rest, or at peak exercise eSBV [(Rest; –75 ml, 95% confidence interval [CI] –279 to 130; p=0.47); and (Peak; –96 mL, 95% CI –444 to 251, p=0.59)]. This was consistent among patients with and without type 2 diabetes, etiology of HFrEF, and diuretic usage (Figure 1). Conclusion: Empagliflozin may contribute to shift blood from the effective circulatory beds to the venous reservoir in reducing filling pressure and eSBV, but maintaining CO.

Abstract Aims This study aimed to describe haemodynamic features of patients with advanced heart failure with preserved ejection fraction (HFpEF) as defined by the Heart Failure Association (HFA) of the European Society of Cardiology (ESC). Methods and results We used pooled data from two dedicated HFpEF studies with invasive exercise haemodynamic protocols, the REDUCE LAP-HF (Reduce Elevated Left Atrial Pressure in Patients with Heart Failure) trial and the REDUCE LAP-HF I trial, and categorized patients according to advanced heart failure (AdHF) criteria. The well-characterized HFpEF patients were considered advanced if they had persistent New York Heart Association classification of III–IV and heart failure (HF) hospitalization &lt; 12 months and a 6 min walk test distance &lt; 300 m. Twenty-four (22%) out of 108 patients met the AdHF criteria. On evaluation, clinical characteristics and resting haemodynamics were not different in the two groups. Patients with AdHF had lower work capacity compared with non-advanced patients (35 ± 16 vs. 45 ± 18 W, P = 0.021). Workload-corrected pulmonary capillary wedge pressure normalized to body weight (PCWL) was higher in AdHF patients compared with non-advanced (112 ± 55 vs. 86 ± 49 mmHg/W/kg, P = 0.04). Further, AdHF patients had a smaller increase in cardiac index during exercise (1.1 ± 0.7 vs. 1.6 ± 0.9 L/min/m2, P = 0.028). Conclusions A significantly higher PCWL and lower cardiac index reserve during exercise were observed in AdHF patients compared with non-advanced. These differences were not apparent at rest. Therapies targeting the haemodynamic compromise associated with advanced HFpEF are needed.

Aims Remote monitoring of pulmonary artery pressure has reduced heart failure (HF) hospitalizations in chronic HF as elevation of pulmonary artery pressure provides information that can guide treatment. The venous system is characterized by high capacitance, thus substantial increases in intravascular volume can occur before filling pressures increase. The inferior vena cava (IVC) is a highly compliant venous conduit and thus a candidate for early detection of change in intravascular volume. We aimed to compare IVC cross‐sectional area using a novel sensor with cardiac filling pressures during experimental manipulation of volume status, vascular tone, and cardiac function. Methods and results Experiments were conducted in sheep to manipulate volume status (colloid infusion), vascular tone (nitroglycerin infusion) and cardiac function (rapid cardiac pacing). A wireless implantable IVC sensor was validated ex‐vivo and in‐vivo , and then used to measure the cross‐sectional area of the IVC. Right‐ and left‐sided cardiac filling pressures were obtained via right heart catheterization. The IVC sensor provided highly accurate and precise measurements of cross‐sectional area in ex‐vivo and in‐vivo validation. IVC area changes were more sensitive than the corresponding changes in cardiac filling pressures during colloid infusion ( p < 0.001), vasodilatation ( p < 0.001) and cardiac dysfunction induced by rapid pacing ( p ≤ 0.02). Conclusions Inferior vena cava area can be remotely and accurately measured in real time with a wireless implantable sensor. Changes in IVC area are more sensitive than corresponding changes in filling pressures following experimental volume loading and fluid redistribution. Additional research is warranted to understand if remote monitoring of the IVC may have advantages over pressure‐based monitors in HF.

Objective Mild aortic valve stenosis (AS) and aortic valve (AV) sclerosis are associated with diastolic dysfunction and increased mortality in the general population. This study specifically investigated the impact of mild AV disease in heart failure with preserved ejection fraction (HFpEF). Methods Consecutive patients hospitalised with HFpEF (n=370) underwent assessment of cardiac structure and function and long-term clinical follow-up. Results In the study cohort, 111 had mild AS (30%), 104 AV sclerosis (28%) and 155 a non-calcified AV (42%). Mild-to-moderate AV regurgitation (AR) was present in 64 (17%). Compared with patients with a normal AV, those with AV disease were older, with worse renal function and more atrial fibrillation. E/e′ increased from non-calcified AV to AV sclerosis to mild AS (13.8 (10.8–16.8) vs 15.0 (10.9–20.0) vs 18.0 (12.7–23.3), respectively; p<0.001)). Left ventricular diastolic pressure–volume relationships were shifted leftwards in patients with AS and AV sclerosis, but not influenced by AR. The left ventricular end-diastolic volume normalised at 20 mm Hg was 117±34 mL, 106±30 mL and 112±30 mL in non-calcified AV, AV sclerosis and mild AS, respectively (p=0.023), while 112±32 mL in mild-to-moderate AR. Over 30 months (IQR, 8–61 months), 247 patients died (67%). The presence of mild AV disease was associated with increased mortality, but this was no longer significant after adjusting for age and sex. Conclusions Low-grade AV disease is common among patients hospitalised for HFpEF and is associated with older age, atrial arrhythmia, renal dysfunction, higher left heart filling pressures and increased left ventricular chamber stiffness.

Abstract Aims Circulating blood volume is functionally divided between the unstressed volume, which fills the vascular space, and stressed blood volume (SBV), which generates vascular wall tension and intravascular pressure. With decreases in venous capacitance, blood functionally shifts to the SBV, increasing central venous pressure and pulmonary venous pressures. Obesity is associated with both elevated venous pressure and heart failure with preserved ejection fraction (HFpEF). To explore the mechanisms underlying this association, we evaluated relationships between blood volume distribution, venous compliance, and body mass in patients with and without HFpEF. Methods and results Subjects with HFpEF ( n = 62) and non‐cardiac dyspnoea (NCD) ( n = 79) underwent invasive haemodynamic exercise testing with echocardiography. SBV was estimated (eSBV) from measured haemodynamic variables fit to a comprehensive cardiovascular model. Compared to NCD, patients with HFpEF displayed a leftward‐shifted central venous pressure–dimension relationship, indicating reduced venous compliance. eSBV was 81% higher at rest and 69% higher during exercise in HFpEF than NCD (both P < 0.0001), indicating reduced venous capacitance. Despite greater augmented eSBV with exercise, the increase in cardiac output was reduced in HFpEF, suggesting operation on the plateau of the Starling curve. Exercise eSBV was directly correlated with higher body mass index (r = 0.77, P < 0.0001) and inversely correlated with right ventricular–pulmonary arterial coupling (r = −0.57, all P < 0.0001). Conclusions Patients with HFpEF display reductions in systemic venous compliance and increased eSBV related to reduced venous capacitance, abnormalities in right ventricular–pulmonary artery interaction, and increased body fat. These data provide new evidence supporting an important role of venous dysfunction in obesity‐related HFpEF and suggest that therapies that improve venous function may hold promise to improve clinical status in this cohort.

Background: There are no specific treatments for patients with HFpEF and pulmonary hypertension (PH-HFpEF). Increased central and pulmonary venous pressures (CVP, PCWP) are believed to contribute importantly to symptoms at rest and during exercise. Levosimendan (LEVO), a calcium sensitizer/KATP channel activator, is known to reduce CVP and PCWP in patients with reduced LVEF. We hypothesized that LEVO would have similar effects in PH-HFpEF. Methods: 44 PH-HFpEF patients with mean pulmonary artery (mPAP) ≥35 mmHg, PCWP ≥20 mmHg, LVEF ≥40% and NYHA II or III symptoms underwent hemodynamic measurements at rest, during passive leg raise (PLR) and during supine bicycle exercise for 3 minutes at 25 Watts (EX) at baseline and following a continuous 24-hour infusion of LEVO (0.1 μg/kg/min) as part of a multicenter clinical trial. Measurements included CVP, mPAP, PCWP, mean arterial pressure (MAP) and cardiac index (CI); pulmonary and systemic vascular resistances (PVR, SVR) were calculated. Hemodynamic tracings were analyzed in a core lab blinded to condition and timepoint. The primary endpoint was the change of PCWP at 25 Watts. Results: Patients averaged 69±9.1 years old, 61.4% were female and had a mPAP of 41.0±9.3 mmHg at rest. LEVO decreased mPAP at rest, CVP and PCWP at rest and EX, and increased CI with EX; there were no significant changes in mPAP, PVR or SVR. Resting and EX hemodynamic data are summarized in the Table. 37 of the 44 patients (84%) were considered hemodynamic “responders” based on a pre-specified ≥4 mmHg decrease of EX PCWP. Conclusions: In patients with PH-HFpEF, a 24 hour levosimendan infusion at 0.1 μg/kg/min decreased CVP and PCWP and increased CI at rest and EX, despite no significant effect on SVR or PVR. A majority of patients exhibited acute hemodynamic response. While the underlying mechanism(s) remain to be clarified, LEVO’s effects on CVP and PCWP warrant further study of this drug as a treatment for PH-HFpEF.

Abstract Aims A hallmark of heart failure with preserved ejection fraction (HFpEF) is impaired exercise capacity of varying severity. The main determinant of exercise capacity is cardiac output (CO), however little information is available about the relation between the constituents of CO – heart rate and stroke volume – and exercise capacity in HFpEF. We sought to determine if a heterogeneity in heart rate and stroke volume response to exercise exists in patients with HFpEF and describe possible clinical phenotypes associated with differences in these responses. Methods and results Data from two prospective trials of HFpEF ( n = 108) and a study of healthy participants ( n = 42) with invasive haemodynamic measurements during exercise were utilized. Differences in central haemodynamic responses were analysed with regression models. Chronotropic incompetence was present in 39–56% of patients with HFpEF and 3–56% of healthy participants depending on the definition used, but some ( n = 47, 44%) had an increase in heart rate similar to that of healthy controls. Patients with HFpEF had a smaller increase in their stroke volume index (SVI) (HFpEF: +4 ± 10 mL/m 2 , healthy participants: +24 ± 12 mL/m 2 , P < 0.0001), indeed, SVI fell in 28% of patients at peak exercise. Higher body mass index and lower SVI at rest were associated with smaller increases in heart rate during exercise, whereas higher resting heart rate, and angiotensin‐converting enzyme inhibitor/angiotensin II receptor blocker use were associated with a greater increase in SVI in patients with HFpEF. Conclusion The haemodynamic response to exercise was very heterogeneous among patients with HFpEF, with chronotropic incompetence observed in up to 56%, and 28% had impaired increase in SVI. This suggests that haemodynamic exercise testing may be useful to identify which HFpEF patients may benefit from interventions targeting stroke volume and chronotropic response.