Catheter-based system for the treatment of left ventricular assist device thrombosis.

BACKGROUND: Thrombotic complications continue to pose challenges to patients on left ventricular assist device (LVAD) support. The Hoplon system was developed to administer catheter-based lytic therapy with a novel approach to embolic protection. METHODS: Two porcine non-survival surgeries were performed in which off-pump LVAD insertion was followed by injection of thrombus into the impeller, isolation of the pump using the Hoplon system, and administration of lytic therapy to the pump chamber. Successful thrombus resolution was confirmed by pathological examination of the LVAD and brain tissue after animal sacrifice. RESULTS: Limitations of the prototype design resulted in the extrusion of thrombus from around the catheter in the first animal. Subsequent device modifications resulted in the resolution of LVAD thrombus as confirmed on removal and examination of the pump. Pathological examination of the brain tissue revealed the absence of any embolic or hemorrhagic complications. CONCLUSIONS: Early animal studies suggest feasibility in restoring function to an LVAD while at the same time preventing cerebroembolic events using the Hoplon system.

Open atrial transcatheter mitral valve replacement in patients with mitral annular calcification.

BACKGROUND: Mitral valve replacement in the setting of severe mitral annular calcification remains a surgical challenge. Transcatheter mitral valve replacement (TMVR) using an aortic balloon-expandable transcatheter heart valve is emerging as a potential treatment option for high surgical risk patients. Transseptal, transapical, or transatrial access is not always feasible, so an understanding of alternative implantation techniques is important. OBJECTIVES: The authors sought to present a step-by-step description of a contemporary transatrial TMVR technique using balloon-expandable aortic transcatheter heart valves. This procedure has evolved over time to address valve migration, left ventricular outflow tract obstruction, and paravalvular leak. The authors present a refined technique that has been associated with the most reproducible outcomes. METHODS: A step-by-step description of the TMVR technique and outcomes of 8 patients treated using this technique are described. Baseline patient clinical and echocardiographic characteristics and 30-day post-TMVR outcomes are presented. RESULTS: Eight patients underwent transatrial TMVR at a single institution. Five had previous cardiac surgery. Mean STS score was 8%. Technical success by MVARC (Mitral Valve Academic Research Consortium) criteria was 100%. There was zero in-hospital and 30-day mortality. Procedural success by MVARC criteria at 30 days was 100%. Paravalvular leak immediately post-implant was none or trace in 6 and mild in 1. CONCLUSIONS: The technique described is reproducible and was associated with favorable outcomes in this early experience. It represents a useful technique for the treatment of mitral valve disease in the setting of severe annular calcification. A structured and defined implantation technique is critical to investigators as this field evolves.

Open Atrial Transcatheter Mitral Valve Replacement in Patients With Mitral Annular Calcification.

BACKGROUND: Mitral valve replacement in the setting of severe mitral annular calcification remains a surgical challenge. Transcatheter mitral valve replacement (TMVR) using an aortic balloon-expandable transcatheter heart valve is emerging as a potential treatment option for high surgical risk patients. Transseptal, transapical, or transatrial access is not always feasible, so an understanding of alternative implantation techniques is important. OBJECTIVES: The authors sought to present a step-by-step description of a contemporary transatrial TMVR technique using balloon-expandable aortic transcatheter heart valves. This procedure has evolved over time to address valve migration, left ventricular outflow tract obstruction, and paravalvular leak. The authors present a refined technique that has been associated with the most reproducible outcomes. METHODS: A step-by-step description of the TMVR technique and outcomes of 8 patients treated using this technique are described. Baseline patient clinical and echocardiographic characteristics and 30-day post-TMVR outcomes are presented. RESULTS: Eight patients underwent transatrial TMVR at a single institution. Five had previous cardiac surgery. Mean STS score was 8%. Technical success by MVARC (Mitral Valve Academic Research Consortium) criteria was 100%. There was zero in-hospital and 30-day mortality. Procedural success by MVARC criteria at 30 days was 100%. Paravalvular leak immediately post-implant was none or trace in 6 and mild in 1. CONCLUSIONS: The technique described is reproducible and was associated with favorable outcomes in this early experience. It represents a useful technique for the treatment of mitral valve disease in the setting of severe annular calcification. A structured and defined implantation technique is critical to investigators as this field evolves.

Effect of Mechanically Expanded vs Self-Expanding Transcatheter Aortic Valve Replacement on Mortality and Major Adverse Clinical Events in High-Risk Patients With Aortic Stenosis: The REPRISE III Randomized Clinical Trial.

Importance: Transcatheter aortic valve replacement (TAVR) is established for selected patients with severe aortic stenosis. However, limitations such as suboptimal deployment, conduction disturbances, and paravalvular leak occur. Objective: To evaluate if a mechanically expanded valve (MEV) is noninferior to an approved self-expanding valve (SEV) in high-risk patients with aortic stenosis undergoing TAVR. Design, Setting, and Participants: The REPRISE III trial was conducted in 912 patients with high or extreme risk and severe, symptomatic aortic stenosis at 55 centers in North America, Europe, and Australia between September 22, 2014, and December 24, 2015, with final follow-up on March 8, 2017. Interventions: Participants were randomized in a 2:1 ratio to receive either an MEV (n = 607) or an SEV (n = 305). Main Outcomes and Measures: The primary safety end point was the 30-day composite of all-cause mortality, stroke, life-threatening or major bleeding, stage 2/3 acute kidney injury, and major vascular complications tested for noninferiority (margin, 10.5%). The primary effectiveness end point was the 1-year composite of all-cause mortality, disabling stroke, and moderate or greater paravalvular leak tested for noninferiority (margin, 9.5%). If noninferiority criteria were met, the secondary end point of 1-year moderate or greater paravalvular leak was tested for superiority in the full analysis data set. Results: Among 912 randomized patients (mean age, 82.8 [SD, 7.3] years; 463 [51%] women; predicted risk of mortality, 6.8%), 874 (96%) were evaluable at 1 year. The primary safety composite end point at 30 days occurred in 20.3% of MEV patients and 17.2% of SEV patients (difference, 3.1%; Farrington-Manning 97.5% CI, -∞ to 8.3%; P = .003 for noninferiority). At 1 year, the primary effectiveness composite end point occurred in 15.4% with the MEV and 25.5% with the SEV (difference, -10.1%; Farrington-Manning 97.5% CI, -∞ to -4.4%; P<.001 for noninferiority). The 1-year rates of moderate or severe paravalvular leak were 0.9% for the MEV and 6.8% for the SEV (difference, -6.1%; 95% CI, -9.6% to -2.6%; P < .001). The superiority analysis for primary effectiveness was statistically significant (difference, -10.2%; 95% CI, -16.3% to -4.0%; P < .001). The MEV had higher rates of new pacemaker implants (35.5% vs 19.6%; P < .001) and valve thrombosis (1.5% vs 0%) but lower rates of repeat procedures (0.2% vs 2.0%), valve-in-valve deployments (0% vs 3.7%), and valve malpositioning (0% vs 2.7%). Conclusions and Relevance: Among high-risk patients with aortic stenosis, use of the MEV compared with the SEV did not result in inferior outcomes for the primary safety end point or the primary effectiveness end point. These findings suggest that the MEV may be a useful addition for TAVR in high-risk patients. Trial Registration: ClinicalTrials.gov Identifier: NCT02202434.

Arterial Cutaneous Femoral Fistulous Tract Closure Using Surgiflo Hemostatic Matrix: A Novel Adjunct for Post-TAVR Access-Site Management.

Several options are available to address hemostasis at the end of a cardiac catheterization or percutaneous transfemoral transcatheter aortic valve replacement (TAVR) when conventional options are ineffective. To date, there have been few studies exploring the use of a topical thrombin preparation, as one of its main contraindications is that it cannot be used intravascularly due to risk of embolization. The following case shows safe utilization of Surgiflo hemostatic gel matrix under fluoroscopic guidance against an inflated balloon in order to achieve closure of a fistulous tract from a femoral artery access site during percutaneous TAVR.

MitraClip Therapy for Mitral Regurgitation: Secondary Mitral Regurgitation.

Therapy for mitral regurgitation (MR) has been synonymous with mitral valve surgery. Operative approaches for degenerative MR repair have been associated with excellent results, with durable long term outcomes. Surgery for functional MR has been less successful. MitraClip has shown promise for functional MR, especiall in patinets who are high risk for surgery. The aggregate of nonrandomized global experience with MitraClip in functional MR has been consistent in showing improvements in symptoms and left ventricular remodeling. It remains to be seen how MitraClip therapy will compare with best medical therapy. The COAPT trial will clarify this question.

Percutaneous vascular plug for incomplete surgical left atrial appendage closure.

Surgical left atrial appendage (LAA) exclusion has a failure rate as high as 60% due to persistent residual flow in the LAA or large LAA remnants. We describe a novel technique for treatment of incomplete surgical LAA ligation, and define the mechanism that led to persistence of the remnant LAA without any thrombus formation.

High pacing rates for management of aortic insufficiency after balloon aortic valvuloplasty or transcatheter aortic valve replacement.

Aortic insufficiency (AI) after transcatheter aortic valve replacement (TAVR) is difficult to manage when associated with congestive heart failure. AI after balloon aortic valvuloplasty (BAV) may be catastrophic, especially in patients who are not candidates for TAVR. We describe the use of urgent temporary pacing, followed by permanent pacing, to increase the heart rate to diminish diastolic filling time for the short term management of AI after BAV or TAVR. The strategy is particularly useful in patients who already have permanent pacemakers, which are common in this population.

Low profile vascular plugs for paravalvular leaks after TAVR.

BACKGROUND: Paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) is associated with less good outcomes. The use of percutaneous plugs is among the strategies to treat PVL after TAVR. Plugs have been limited by the need to pass 4-6 F delivery sheaths between the TAVR stent frame and the native valve leaflets. METHODS: The study population consists of six patients who had at least moderate aortic insufficiency (AI), and also developed symptoms of heart failure after TAVR. We describe in detail the use of low profile vascular plugs that require crossing the leaks with only a 4 F diagnostic catheter. RESULTS: Low profile vascular plugs were successfully deployed in all six patients without significant complications. Fluoroscopy time ranged 16.7-69.4 min (44.8 ± 18.8 min). Contrast volume ranged 15-100 mL (45 ± 34 mL). One plug was used in five, and two adjacent plus in one case. AI severity was reduced from moderate or severe to mild or less in four patients, from severe to moderate in one, and in one, there was no change. Five of six patients were treated electively and were significantly improved in terms of both echocardiographic PVL and also symptoms. The one who did not have echocardiographic improvement did not improve clinically and expired one month later. CONCLUSIONS: PVL closure can be consistently accomplished after TAVR with low profile vascular plugs. Careful analysis of PVL location on echo before closure greatly facilitates finding the fluoroscopic location of the leak. Decreases in PVL severity are associated with significant clinical improvement.

Antegrade approach for TAVR with total occlusion of the descending aorta.

The antegrade approach for aortic valve interventions is well known but has not been widely used for transcatheter aortic valve replacement (TAVR) procedures. We encountered a patient with no possibility of retrograde access due to a totally occluded abdominal aorta who had a failed attempt at apical TAVR. We describe antegrade TAVR despite occlusion of the abdominal aorta, with the arterial limb of the requisite veno-arterial loop created using bilateral arm access, a novel version of the previously described antegrade approach.

Fluoroscopically-guided micropuncture femoral artery access for large-caliber sheath insertion.

Over the last decade, significant developments have been made in the treatment of structural heart disease. Some of these techniques require placement of large arterial sheaths for device delivery. Optimal vascular access is essential for successful large-vessel sheath insertion as well as to avoid vascular complications. The critical step for ideal percutaneous vessel entry is single anterior wall-only puncture of the common femoral artery in a location above the femoral bifurcation and below the inguinal ligament. We describe a fluoroscopically-guided micropuncture technique for accurate placement of large-caliber arterial sheaths.

Cardiac MRI documented left ventricular thrombus complicating acute Takotsubo syndrome: an uncommon dilemma.

Transient left ventricular apical hypokinesis results in a typical ampullary shape and has been described as Takotsubo cardiomyopathy (TCM). We report a case of TCM with the rare complication of left ventricular thrombus formation. Cardiac magnetic resonance imaging aided the diagnosis by characterizing the non-enhancing mass and evaluating the surrounding myocardium for scarring.

Successful closure of a giant true saphenous vein graft aneurysm using the Amplatzer vascular plug.

An 85-year-old man was found to have a 9 cm diameter true aneurysm of an obtuse marginal saphenous vein graft. The graft was fed by a relatively narrow neck from the proximal remnant of the obtuse marginal graft 10 years after prior coronary artery bypass graft surgery. An Amplatzer vascular plug was used successfully to occlude the neck of the aneurysm. Follow-up CT scan 1 month afterward demonstrated retained contrast in the aneurysm, demonstrating complete occlusion between the aorta and aneurysm sac. Pressure recordings from within the aneurysm sac suggest bidirectional flow in the neck as the mechanism for the maintained patency of the aneurysm. The use of a vascular plug is an effective method for aneurysm occlusion when the anatomy is suitable.

Percutaneous closure of an aorta to left atrium fistula with an Amplatzer duct occluder.

We describe percutaneous closure of an unusual paravalvular leak, with a communication from the noncoronary cusp of the aortic valve to the left atrium adjacent to a St. Jude mitral valve prosthesis, in the absence of an infection. The patient presented with worsening dyspnea and edema. The anatomic location of the valve annulus adjacent to the noncoronary cusp underlies the etiology of this communication. Outcomes from surgical repair are associated with high mortality. We performed percutaneous closure of the defect, using general anesthesia and transesophageal echo guidance. An Amplatzer duct occluder was placed in the fistula, with immediate and complete closure of the shunt. While no devices specific for closure of paravalvular leaks have been designed, growing experience with a variety of devices and the use of echo guidance have allowed successful therapy in many complex cases.

Percutaneous balloon aortic valvuloplasty: antegrade transseptal vs. conventional retrograde transarterial approach.

Percutaneous balloon aortic valvuloplasty (BAV) has been limited predominantly to a palliative treatment for poor surgical candidates with critical aortic stenosis and multiple high-risk or comorbid conditions. The most commonly used technique for BAV is the retrograde approach, in which the balloon is passed via the femoral artery using 12-14 Fr sheaths. We compared an antegrade transseptal approach using the Inoue balloon vs. the retrograde transarterial approach using conventional balloons. The antegrade group had an improved acute hemodynamic outcome, including 20% additional increase of aortic valve area and 20% greater reduction of transaortic valve gradient compared to the retrograde approach. Preclosure with the Perclose device was used for the 14 Fr venous access sites, resulting in immediate hemostasis, minimizing the need for transfusion, and diminishing the period of bed rest. The improved acute efficacy and relative ease of venous access for the antegrade approach facilitate BAV by eliminating the need for large-caliber arterial access sheaths. The antegrade approach also incorporates technical elements necessary for percutaneous aortic valve replacement and may have expanded applications as an adjunct to this developing therapy. The impact of improved acute results on the long-term clinical outcome for this patient group will require further study.