Endovascular Ablation of the Right Greater Splanchnic Nerve in Heart Failure With Preserved Ejection Fraction: Rationale, Design and Lead-in Phase Results of the REBALANCE-HF Trial

OBJECTIVE

Splanchnic vasoconstriction augments transfer of blood volume from the abdomen into the thorax, which may increase filling pressures and hemodynamic congestion in patients with noncompliant hearts. Therapeutic interruption of splanchnic nerve activity holds promise to reduce hemodynamic congestion in patients with heart failure with preserved ejection fraction (HFpEF). Here we describe (1) the rationale and design of the first sham-controlled, randomized clinical trial of splanchnic nerve ablation for HFpEF and (2) the 12-month results of the lead-in (open-label) trial's participants.

METHODS

REBALANCE-HF is a prospective, multicenter, randomized, double-blinded, sham-controlled clinical trial of endovascular, transcatheter, right-sided greater splanchnic nerve ablation for volume management (SAVM) in patients with HFpEF. The primary objectives are to evaluate the safety and efficacy of SAVM and identify responder characteristics to inform future studies. The trial consists of an open-label lead-in phase followed by the randomized, sham-controlled phase. The primary efficacy endpoint is the reduction in pulmonary capillary wedge pressure (PCWP) at 1-month follow-up compared to baseline during passive leg raise and 20W exercise. Secondary and exploratory endpoints include health status (Kansas City Cardiomyopathy Questionnaire), 6-minute walk test distance, New York Heart Association class, and NTproBNP levels at 3, 6 and 12 months. The primary safety endpoint is device- or procedure-related serious adverse events at the 1-month follow-up.

RESULTS

The lead-in phase of the study, which enrolled 26 patients with HFpEF who underwent SAVM, demonstrated favorable safety outcomes and reduction in exercise PCWP at 1 month post-procedure and improvements in all secondary endpoints at 6 and 12 months of follow-up. The randomized phase of the trial (n = 44 SAVM; n = 46 sham) has completed enrollment, and follow-up is ongoing.

CONCLUSION

REBALANCE-HF is the first sham-controlled randomized clinical trial of greater splanchnic nerve ablation in HFpEF. Initial 12-month open-label results are promising, and the results of the randomized portion of the trial will inform the design of a future pivotal clinical trial. SAVM may offer a promising therapeutic option for patients with HFpEF.

TRIAL REGISTRATION

NCT04592445.

Exercise-Induced Left Atrial Hypertension in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Many patients with heart failure and preserved ejection fraction have no overt volume overload and normal resting left atrial (LA) pressure.

OBJECTIVES

This study sought to characterize patients with normal resting LA pressure (pulmonary capillary wedge pressure [PCWP] <15 mm Hg) but exercise-induced left atrial hypertension (EILAH).

METHODS

The 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) trial randomized 626 patients with ejection fraction ≥40% and exercise PCWP ≥25 mm Hg to atrial shunt or sham procedure. The primary trial outcome, a hierarchical composite of death, heart failure hospitalization, intensification of diuretics, and change in health status was compared between patients with EILAH and those with heart failure and resting left atrial hypertension (RELAH).

RESULTS

Patients with EILAH (29%) had similar symptom severity, but lower natriuretic peptide levels, higher 6-minute walk distance, less atrial fibrillation, lower left ventricular mass, smaller LA volumes, lower E/e', and better LA strain. PCWP was lower at rest, but had a larger increase with exercise in EILAH. Neither group as a whole had a significant effect from shunt therapy vs sham. Patients with EILAH were more likely to have characteristics associated with atrial shunt responsiveness (peak exercise pulmonary vascular resistance <1.74 WU) and no pacemaker (63% vs 46%; P < 0.001). The win ratio for the primary outcome was 1.56 (P = 0.08) in patients with EILAH and 1.51 (P = 0.04) in those with RELAH when responder characteristics were present.

CONCLUSIONS

Patients with EILAH had similar symptom severity but less advanced myocardial and pulmonary vascular disease. This important subgroup may be difficult to diagnose without invasive exercise hemodynamics, but it has characteristics associated with favorable response to atrial shunt therapy. (A Study to Evaluate the Corvia Medical, Inc. IASD System II to Reduce Elevated Left Atrial Pressure in Patients With Heart Failure [REDUCE LAP-HF TRIAL II]; NCT03088033).

Comparison of a Complete Percutaneous Versus Surgical Approach to Aortic Valve Replacement and Revascularization in Patients at Intermediate Surgical Risk: Results From the Randomized SURTAVI Trial

BACKGROUND

For patients with severe aortic stenosis and coronary artery disease, the completely percutaneous approach to aortic valve replacement and revascularization has not been compared with the standard surgical approach.

METHODS

The prospective SURTAVI trial (Safety and Efficiency Study of the Medtronic CoreValve System in the Treatment of Severe, Symptomatic Aortic Stenosis in Intermediate Risk Subjects Who Need Aortic Valve Replacement) enrolled intermediate-risk patients with severe aortic stenosis from 87 centers in the United States, Canada, and Europe between June 2012 and June 2016. Complex coronary artery disease with SYNTAX score (Synergy Between PCI with Taxus and Cardiac Surgery Trial) >22 was an exclusion criterion. Patients were stratified according to the need for revascularization and then randomly assigned to treatment with transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). Patients assigned to revascularization in the TAVR group underwent percutaneous coronary intervention, whereas those in the SAVR group had coronary artery bypass grafting. The primary end point was the rate of all-cause mortality or disabling stroke at 2 years.

RESULTS

Of 1660 subjects with attempted aortic valve implants, 332 (20%) were assigned to revascularization. They had a higher Society of Thoracic Surgeons risk score for mortality (4.8±1.7% versus 4.4±1.5%; P<0.01) and were more likely to be male (65.1% versus 54.2%; P<0.01) than the 1328 patients not assigned to revascularization. After randomization to treatment, there were 169 patients undergoing TAVR and percutaneous coronary intervention, 163 patients undergoing SAVR and coronary artery bypass grafting, 695 patients undergoing TAVR, and 633 patients undergoing SAVR. No significant difference in the rate of the primary end point was found between TAVR and percutaneous coronary intervention and SAVR and coronary artery bypass grafting (16.0%; 95% CI, 11.1-22.9 versus 14.0%; 95% CI, 9.2-21.1; P=0.62), or between TAVR and SAVR (11.9%; 95% CI, 9.5-14.7 versus 12.3%; 95% CI, 9.8-15.4; P=0.76).

CONCLUSIONS

For patients at intermediate surgical risk with severe aortic stenosis and noncomplex coronary artery disease (SYNTAX score ≤22), a complete percutaneous approach of TAVR and percutaneous coronary intervention is a reasonable alternative to SAVR and coronary artery bypass grafting.

CLINICAL TRIAL REGISTRATION

URL: https://www.

CLINICALTRIALS

gov. Unique identifier: NCT01586910.

Neurological Events Following Transcatheter Aortic Valve Replacement and Their Predictors: A Report From the CoreValve Trials

BACKGROUND

The risk for stroke after transcatheter aortic valve replacement (TAVR) is an important concern. Identification of predictors for stroke is likely to be a critical factor aiding patient selection and management as TAVR use becomes widespread.

METHODS AND RESULTS

Patients enrolled in the CoreValve US Extreme Risk and High Risk Pivotal Trials or Continued Access Study treated with the self-expanding CoreValve bioprosthesis were included in this analysis. The 1-year stroke rate after TAVR was 8.4%. Analysis of the stroke hazard rate identified an early phase (0-10 days; 4.1% of strokes) and a late phase (11-365 days; 4.3% of strokes). Baseline predictors of early stroke included National Institutes of Health stroke scale score >0, prior stroke, prior transient ischemic attack, peripheral vascular disease, absence of prior coronary artery bypass surgery, angina, low body mass index (<21 kg/m(2)), and falls within the past 6 months. Significant procedural predictors were total time in the catheterization laboratory or operating room, delivery catheter in the body time, rapid pacing used during valvuloplasty, and repositioning of the prosthesis. Predictors of stroke between 11 and 365 days were small body surface area, severe aortic calcification, and falls within the past 6 months. There were no significant imaging predictors of early or late stroke.

CONCLUSIONS

Predictors of early stroke after TAVR included clinical and procedural factors; predictors of later stroke were limited to patient but not anatomic characteristics. These findings indicate that further refinement of imaging to identify anatomic factors predisposing to embolization may help improve stroke prediction in patients undergoing TAVR.

CLINICAL TRIAL REGISTRATIONS

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01240902, NCT01531374.

The acute hemodynamic effects of MitraClip therapy

OBJECTIVES

The objective of this study was to evaluate the acute hemodynamic consequences of mitral valve (MV) repair with the MitraClip device (Abbott Vascular, Menlo Park, California).

BACKGROUND

Whether surgical correction of mitral regurgitation (MR) results in a low cardiac output (CO) state because of an acute increase in afterload remains controversial. The acute hemodynamic consequences of MR reduction with the MitraClip device have not been studied.

METHODS

We evaluated 107 patients with cardiac catheterization before and immediately following percutaneous MV repair with the MitraClip device. In addition, pre- and post-procedural hemodynamic parameters were studied by transthoracic echocardiography.

RESULTS

MitraClip treatment was attempted in 107 patients, and in 96 (90%) patients, a MitraClip was deployed. Successful MitraClip treatment resulted in: 1) an increase in CO from 5.0 ± 2.0 l/min to 5.7 ± 1.9 l/min (p = 0.003); 2) an increase in forward stroke volume (FSV) from 57 ± 17 ml to 65 ± 18 ml (p < 0.001); and 3) a decrease in systemic vascular resistance from 1,226 ± 481 dyn·s/cm(5) to 1,004 ± 442 dyn·s/cm(5) (p < 0.001). In addition, there was left ventricular (LV) unloading manifested by a decrease in LV end-diastolic pressure from 11.4 ± 9.0 mm Hg to 8.8 ± 5.8 mm Hg (p = 0.016) and a decrease in LV end-diastolic volume from 172 ± 37 ml to 158 ± 38 ml (p < 0.001). None of the patients developed acute post-procedural low CO state.

CONCLUSIONS

Successful MV repair with the MitraClip system results in an immediate and significant improvement in FSV, CO, and LV loading conditions. There was no evidence of a low CO state following MitraClip treatment for MR. These favorable hemodynamic effects with the MitraClip appear to reduce the risk of developing a low CO state, a complication occasionally observed after surgical MV repair for severe MR.

Effect of percutaneous mitral repair with the MitraClip device on mitral valve area and gradient

AIMS

Percutaneous repair of mitral regurgitation (MR) by leaflet apposition using a clip deployed via transseptal catheterisation is undergoing evaluation.

METHODS AND RESULTS

In order to detect the potential for clinically significant left ventricular inflow obstruction after percutaneous repair, we measured mitral valve area (MVA) and mean transmitral gradient (MVG) echocardiographically in 96 patients implanted with a clip followed for up to 24 months. By planimetry, the mean MVA decreased from 6.0 +/- 1.3 cm2 to 3.6 +/- 1.2 cm2 (p < 0.05) (range 1.9 to 7.6 cm2) after clip placement, and remained unchanged after 24 months of follow-up (3.5 +/- 0.8 cm2). The mean MVG increased after clip placement from 1.7 +/- 0.9 mmHg to 4.1 +/- 2.2 mmHg (p < 0.05), and did not increase further to 24 months (3.8 +/- 1.9 mmHg). There were no differences in MVA or MVG between patients who received 1-clip (69%) and those receiving 2-clips (31%). Patients with functional MR (23%) had a slightly smaller MVA, both at baseline and after clip placement, but did not differ from degenerative MR patients at later follow-up. After 2 years of follow-up, no patient required surgery for LV inflow obstruction.

CONCLUSIONS

Mitral repair with the MitraClip device for MR decreases MVA without significant mitral obstruction. After 2 years of follow-up, no patient required surgery for LV inflow obstruction, and these results were not influenced by the use of more than 1 clip or the aetiology of MR.

Midterm Outcomes From the TALON Registry:Treating Peripherals With SilverHawk:Outcomes Collection

PURPOSE

To determine midterm clinical outcomes among patients with lower extremity peripheral arterial disease who underwent revascularization with catheter-based plaque excision (PE).

METHODS

Between August 2003 and February 2005, 19 institutions participating in the observational, nonrandomized, multicenter TALON registry enrolled 601 consecutive patients (353 men; mean age 70+/-11, range 36-98) with 1258 symptomatic lower extremity atherosclerotic lesions (748 limbs) treated by plaque excision with the SilverHawk catheter. Approximately 50% of the patients had diabetes, and nearly one third of the procedures were indicated for Rutherford ischemia category > or =4. Mean lesion lengths above and below the knee, respectively, were 62.5+/-68.5 mm (interquartile range [IQR], 20.0-80.0) and 33.4+/-42.7 mm (IQR 15.0-37.5). The primary endpoints of the study were target lesion revascularization (TLR) at 6 and 12 months.

RESULTS

The device achieved < or =50% residual diameter stenosis in 94.7% of lesions; procedural success was 97.6%. Nearly half (41.9%) of the procedures involved PE of > or =2 lesions. Nearly three quarters (73.3%) of the lesions did not require adjunctive therapy, and stent placement following PE occurred in only 6.3% of lesions. The 6- and 12-month rates of survival free of TLR were 90% and 80%, respectively. Rates of TLR were similar among patients with diabetes (11%) and without diabetes (9%). In the multivariate analysis, significant predictors of TLR at 6 months were a history of MI or coronary revascularization (HR 5.49, 95% CI 1.87 to 16.10, p=0.0008), multiple (> or =2) lesions (HR 1.37, 95% CI 1.11 to 1.70, p=0.0019), and increasing Rutherford category (HR 1.84, 95% CI 1.28 to 2.65, p=0.0003). Lesion length >50 mm was associated with a 2.9-fold increased risk for TLR (HR 2.88, 95% CI 1.18 to 7.01, p=0.012); lesion length >100 mm was associated with a 3.3-fold increase in TLR (HR 3.32, 95% CI 1.15 to 9.56, p=0.016).

CONCLUSION

In patients undergoing revascularization for lower extremity atherosclerotic disease, catheter-based PE achieves favorable procedural success and avoids the need for repeat revascularization at midterm follow-up. These findings support PE as a primary endovascular therapy for patients undergoing lower extremity arterial revascularization.

Procedural and Clinical Outcomes With Catheter-Based Plaque Excision in Critical Limb Ischemia

PURPOSE

To examine the safety and efficacy of catheter-based plaque excision as an alternative therapy to surgery, conventional angioplasty, and/or stenting in high-risk patients with critical limb ischemia (CLI).

METHODS

Between August 2003 and August 2004, a prospective evaluation was conducted of consecutive patients with CLI (Rutherford category>or=5) who were treated with endovascular plaque excision at 7 institutions. This study enrolled 69 patients (37 women; mean age 70+/-12 years, range 43-93) with CLI involving 76 limbs. Clinical outcomes were prospectively followed for 6 months. The primary endpoint was major adverse events (death, myocardial infarction, unplanned amputation, or repeat target vessel revascularization) at 30 days. Visible healing of ulcerated tissue, avoidance of any amputation, and performance of less extensive amputation than initially planned were also assessed.

RESULTS

Procedural success was achieved in 99% of cases. Major adverse events occurred in 1% of patients at 30 days and 23% at 6 months. The target lesion revascularization rate was 4%, and there were no unplanned limb amputations. Amputation was less extensive than initially planned or avoided altogether in 92% of patients at 30 days and 82% at 6 months.

CONCLUSION

Catheter-based plaque excision is a safe and effective revascularization method for patients with CLI. These findings support further study of this modality as a singular or adjunctive endovascular therapy for limb salvage in CLI.

Safety and efficacy of staple-mediated femoral arteriotomy closure: Results from a randomized multicenter study

BACKGROUND

Mechanical closure of percutaneous femoral arteriotomies following catheter based procedures remains problematic.

METHODS

The EVS closure device is the first to utilize a staple to effect arteriotomy closure and was compared to manual compression following sheath removal in a 362 patient randomized (2:1 to device) multicenter trial. As pre-specified, one half of the patients underwent coronary intervention.

RESULTS

Time to hemostasis was significantly reduced in the EVS group for both diagnostic (3.3 +/- 2.6 vs. 19.3 +/- 5.7 minutes; p < 0.001) and interventional procedures (5.5 +/- 5.1 vs. 22.3 +/- 9.9 minutes; p < 0.0001). Time to ambulation was similarly reduced in the EVS group following diagnostic (2.4 +/- 3.3 vs. 6.0 +/- 5.2 hours; p < 0.001) and interventional procedures (3.4 +/- 4.5 vs. 7.6 +/- 7.0 hours; p < 0.001). The incidence of major complications was similar between the EVS and manual compression groups at discharge (0.4% vs. 1.7%; p = NS) and at 30 day follow-up (0.4% vs. 2.5%; p = NS).

CONCLUSION

Compared to manual compression, the EVS device provides a safe and effective method of femoral artery closure.