Caval-aortic access to allow transcatheter aortic valve replacement in otherwise ineligible patients: initial human experience

An Updated Comprehensive Review of Existing Transcatheter Aortic Valve Replacement Access

For the past 20 years, transcatheter aortic valve replacement (TAVR) has been the treatment of choice for symptomatic aortic stenosis. The transfemoral (TF) access is considered the gold standard approach for TAVR. However, TF-TAVR cannot be performed in some patients; thus, alternative accesses are required. Our review paper generalises the TAVR accesses currently available, including the transapical, transaortic, trans-subclavian/axillary, transcarotid, transcaval, and suprasternal approaches. Their advantages and disadvantages have been analysed. Since there is no standard recommendation for an alternative approach, access selection depends on the expertise of the local cardiac team, patient characteristics, and access properties. Each TAVR centre is recommended to master a minimum of one non-TF access alternative. Of note, more evidence is required to delve into the clinical outcomes of each approach, at both early and long-term (Figure 1).

Alternative access in transcatheter aortic valve replacement-an updated focused review

Aortic Stenosis (AS) is a common condition with an estimated pooled prevalence of all AS in the elderly population at around 12.4%, with that of severe AS estimated to be around 3.4%. In the past, surgical aortic valve replacement was the primary treatment option for severe AS for decades. However, with the compelling evidence on the safety and efficacy of transcatheter aortic valve replacement (TAVR), it has become the gold standard treatment option for many patients with symptomatic severe AS. Transfemoral access has been the preferred method for transcatheter heart valve delivery. However, the prevalent use of TAVR on a diverse patient profile with different risk factors, such as peripheral artery disease, precluded the possibility of a transfemoral approach despite the improvement of valves and delivery systems technology. Therefore, alternative TAVR approaches have gained increasing utility in cases where transfemoral access is unfavorable. We review the journey, evolution, and techniques for different approaches of percutaneous TAVR, including transfemoral, transcarotid, transsubclavian/transaxillary, and transcaval approaches, in addition to the traditional "surgical" transaortic and transapical accesses. Consolidating these data highlights each approach's practicality and limitations, providing additional grounding for case-by-case utilization and future clinical research.

Alternative Access for TAVR: Choosing the Right Pathway

Transcatheter aortic valve replacement (TAVR) has emerged as an alternative treatment option for patients with severe aortic stenosis regardless of surgical risk, particularly in those with a high and prohibitive risk. Since the advent of TAVR, transfemoral access has been the standard of care. However, given comorbidities and anatomical limitations, a proportion of patients are not good candidates for a transfemoral approach. Alternative access, including transapical, transaortic, transaxillary, transsubclavian, transcarotid, and transcaval, can be considered. Each alternative access has advantages and disadvantages, so the vascular route should be tailored to the patient's characteristics. However, there is no standardized algorithm when choosing the optimal alternative vascular access. In this review, we analyzed the evolution and current evidence for the most common alternative access for TAVR and proposed an algorithm for choosing the optimal vascular access in this patient population.

Transcaval approach for aortic endoprosthesis insertion. A new anesthetic challenge

The treatment of acute aortic syndrome has been benefited in recent years from the huge progress in endovascular techniques, compared to classical surgical treatment, by open surgery. Nevertheless, for endovascular treatment to be successful, it is essential for the patient to present adequate vascular access. Those cases with unfavourable vascular anatomy make it necessary to consider open surgery with significant morbidity, or even to reject surgery. A new approach to the abdominal aorta has recently been described as an indication for these patients with impossibility of other vascular access and absolute or relative contraindication to the transthoracic approach. The anesthetic management of the aortic syndrome is well known and, even though there are a variety of options, all of them have proven safety and efficacy. The implementation of new surgical approaches and new possible complications imply a challenge for the anesthesiologist which, for now, has little or none scientific evidence. We present the first case of transcaval aortic endoprosthesis implantation in Spain, its anesthetic implications, and a review of the literature.

Outcomes and Safety of Transcaval Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-analysis

BACKGROUND

The transcaval (TCv) vascular approach is increasingly used in transcatheter aortic valve replacement (TAVR) in patients unsuitable for the gold-standard transfemoral approach. We aimed to evaluate the efficacy, safety, and clinical outcomes associated with TCv-TAVR.

METHODS

A systematic review and meta-analysis was conducted by searching PubMed/Medline, Embase, and the Cochrane Library for all articles assessing the TCv approach published through December 2023. Outcomes included 30-day and 1-year all-cause mortality (ACM), 30-day rehospitalisation, perioperative complications and postoperative complications at 30 days. The meta-analysis was registered on the PROSPERO database with the identifier CRD42024501921.

RESULTS

A total of 8 studies with 467 patients were included. TCv-TAVR procedures achieved a success rate of 98.5%. TCv-TAVR was associated with a 30-day ACM rate of 6.1% (95% confidence interval [CI]: 3.9%-8.2%), a 1-year ACM rate of 14.9% (95% CI 2.3%-27.6%) and a 30-day rehospitalisation rate of 4.2% (95% CI -2.2% to 10.6%). Postoperative stroke or transient ischemic attack, major vascular complications, and major or life-threatening bleeding occurred in 3.3%, 8.7%, and 7.5% of cases, respectively. Cumulative meta-analyses showed a temporal trend of decreasing rates of vascular complications.

CONCLUSIONS

The TCv approach in TAVR demonstrated a reassuring efficacy and safety profile, with mortality and postoperative complication rates similar to those reported for supra-aortic alternative TAVR access routes. The temporal decrease in vascular complications suggests potential improvements in procedural techniques and device technology. These findings further support the TCv approach as a viable option in patients ineligible for the transfemoral access.

PROSPERO

CRD42024501921.

Transcaval versus Supra-Aortic Vascular Accesses for Transcatheter Aortic Valve Replacement: A Systematic Review with Meta-Analysis

A growing body of evidence suggests that extrathoracic vascular accesses for transcatheter aortic valve replacement (TAVR) yield favorable outcomes and can be considered as primary alternatives when the gold-standard transfemoral access is contraindicated. Data comparing the transcaval (TCv) to supra-aortic (SAo) approaches (transcarotid, transsubclavian, and transaxillary) for TAVR are lacking. We aimed to compare the outcomes and safety of TCv and SAo accesses for TAVR as alternatives to transfemoral TAVR. A systematic review with meta-analysis was performed by searching PubMed/MEDLINE and EMBASE databases for all articles comparing TCv-TAVR against SAo-TAVR published until September 2023. Outcomes included in-hospital or 30-day all-cause mortality (ACM) and postoperative complications. A total of three studies with 318 TCv-TAVR and 179 SAo-TAVR patients were included. No statistically significant difference was found regarding in-hospital or 30-day ACM (relative risk [RR] 1.04, 95% confidence interval [CI] 0.47-2.34, p = 0.91), major bleeding, the need for blood transfusions, major vascular complications, and acute kidney injury. TCv-TAVR was associated with a non-statistically significant lower rate of neurovascular complications (RR 0.39, 95%CI 0.14-1.09, p = 0.07). These results suggest that both approaches may be considered as first-line alternatives to transfemoral TAVR, depending on local expertise and patients' anatomy. Additional data from long-term cohort studies are needed.

Trans-Brachial TAVI in a Patient with Aortic Isthmus Stenosis: A Case Report

BACKGROUND

TAVI indications expand not only to low-risk patients but also to patients with a more complex anatomy and comorbidities. Transfemoral retrograde access is recognized as the first preferred approach according to the current guidelines. However, this approach is not suitable in up to 10-15% of patients, for whom an alternative non-femoral access route is required.

CASE PRESENTATION

An 83-year-old male patient with known aortic isthmus stenosis presented with severe symptomatic aortic stenosis. Computed tomography revealed a subtotal isthmus stenosis, directly after left subclavian artery origin, with many collaterals extending toward the axillary and subclavian arteries. Duplex ultrasound verified the proximal diameter of the left brachial artery to be 5.5 mm. A successful surgical cutdown trans-brachial TAVI with an Evolut prosthetic valve with a size of 29 mm was performed. On the fourth postoperative day, the patient was discharged, and the three-month follow-up was uneventful.

CONCLUSION

In patients with aortic isthmus stenosis, the brachial artery could be a feasible alternative, as a less invasive access site, which can be determined after careful assessment of the vessel diameter. More data are required to evaluate the safety and efficacy of this access route and to achieve more technical improvements to increase operator familiarity with it.

Transcatheter Aortic Valve Implantation Access Sites: Same Goals, Distinct Aspects, Various Merits and Demerits

Transcatheter aortic valve implantation (TAVI) has been established as a safe and efficacious treatment for patients with severe symptomatic aortic stenosis (AS). Despite being initially developed and indicated for high-surgical-risk patients, it is now offered to low-risk populations based on the results of large randomized controlled trials. The most common access sites in the vast majority of patients undergoing TAVI are the common femoral arteries; however, 10-20% of the patients treated with TAVI require an alternative access route, mainly due to peripheral atherosclerotic disease or complex anatomy. Hence, to achieve successful delivery and implantation of the valve, several arterial approaches have been studied, including transcarotid (TCr), axillary/subclavian (A/Sc), transapical (TAp), transaortic (TAo), suprasternal-brachiocephalic (S-B), and transcaval (TCv). This review aims to concisely summarize the most recent literature data and current guidelines as well as evaluate the various access routes for TAVI, focusing on the indications, the various special patient groups, and the advantages and disadvantages of each technique, as well as their adverse events.

Transvenous Access for Emergent Thoracic and Thoracoabdominal Aortic Aneurysm Repair in Patients Without Femoral Access

PURPOSE

To describe the technique of transvenous access for emergent endovascular repair of thoracic and thoracoabdominal aneurysms exemplified with 2 cases.

TECHNIQUE

Transvenous access to the aorta is described as an alternative access method to deliver aortic endografts in emergency situations. A 68-year-old female patient with severely compromised iliac and subclavian artery access was treated for a ruptured extent V thoraco-abdominal aortic aneurysm with a t-Branch (Cook Medical, Bjaeverskov, Denmark) delivered through a transcaval access. To avoid severe aortocaval shunting a balloon-expandable covered stent was deployed through a carotid access due to severe bilateral subclavian ostial stenosis. A 71-year-old man with an acute type B aortic dissection and bilateral narrow long-segment stenting of the iliac arteries was treated with a physician-modified thoracic endovascular aortic repair using an arteriovenous fenestration created at the level of the common iliac artery. We describe the access creation by fenestration using a transseptal needle.

CONCLUSION

Transvenous access for thoracic and thoraco-abdominal aortic aneurysm repair is safe and feasible in selected emergent cases.

CLINICAL IMPACT

A transvenous approach may be helpful in selected patients when an endovascular repair needs to be performed but no arterial femoral access is available. This approach proved to be feasible even with large-bore introducer sheaths, taking its place in the armamentarium of the vascular surgeon for emergent complex endovascular aortic repairs.

Outcomes of Alternative Access Transcatheter Aortic Valve Replacement Procedures

Alternative access transcatheter aortic valve replacement (TAVR) consists primarily of 4 different options: transcaval, transaxillary, transcarotid, and transapical. While many centers have a preferred alternative access site, few papers have compared the outcomes of TAVR with each alternative access site. In this review, we examine the outcomes of TAVR at each alternative access site, focusing on mortality, stroke, bleeding, pacemaker insertion, paravalvular leakage, and discharge to home. Notable findings include higher mortality in the transapical group and higher stroke rate in the transaxillary group. On the basis of these data, we suggest that transcarotid TAVR might represent the second choice of approach for TAVR when alternate access is required.

Transcatheter Electrosurgery: A Narrative Review

Transcatheter electrosurgery describes the ability to cut and traverse tissue, at a distance, without an open surgical field and is possible using either purpose-built or off-the-shelf devices. Tissue traversal requires focused delivery of radiofrequency energy to a guidewire tip. Initially employed to cross atretic pulmonary valves, tissue traversal has enabled transcaval aortic access, recanalization of arterial and venous occlusions, transseptal access, and many other techniques. To cut tissue, the selectively denuded inner curvature of a kinked guidewire (the Flying-V) or a single-loop snare is energized during traction. Adjunctive techniques may complement or enable contemporary transcatheter procedures, whereas myocardial slicing or excision of ectopic masses may offer definitive therapy. In this contemporary review we discuss the principles of transcatheter electrosurgery, and through exemplary clinical applications highlight the range of therapeutic options offered by this versatile family of procedures.

Transcaval Access and Closure Best Practices

Transcaval aortic access is a versatile electrosurgical technique for large-bore arterial access through the wall of the abdominal aorta from the adjoining inferior vena cava. Although counterintuitive, its relative safety derives from the recognition that interstitial hydraulic pressure exceeds venous pressure, so arterial bleeding harmlessly decompresses into the nearby caval venous hole. Transcaval access has been performed in thousands of patients for transcatheter aortic valve replacement and endovascular thoracic aneurysm repair and to avoid limb ischemia in percutaneous mechanical circulatory support. Transcaval access may have value compared with transaxillary or subclavian access and with surgical transcarotid access when standard transfemoral access is not optimal. The dissemination of transcaval access and closure techniques has been hampered by the unavailability of commercially marketed devices. This state-of-the-art review details exemplary transcaval technique, patient selection, computed tomographic planning, step-by-step access and closure, management of complications, and procedural troubleshooting in special situations. These contemporary best practices can help operators gain or maintain proficiency.

Management of Vascular Access in the Setting of Percutaneous Mechanical Circulatory Support (pMCS): Sheaths, Vascular Access and Closure Systems

The use of percutaneous mechanical circulatory support (pMCS), such as intra-aortic balloon pump, Impella, TandemHeart and VA-ECMO, in the setting of cardiogenic shock or in protect percutaneous coronary intervention (protect-PCI) is rapidly increasing in clinical practice. The major problem related to the use of pMCS is the management of all the device-related complications and of any vascular injury. MCS often requires large-bore access, if compared with common PCI, and for this reason the correct management of vascular access is a crucial point. The correct use of these devices in catheterization laboratories requires specific knowledge such as the correct evaluation of the vascular access performed, when possible, with advance imaging techniques in order to choose a percutaneous or a surgical approach. In addition to conventional transfemoral access, other types of access, such as transaxillary/subclavial access and the transcaval approach, have emerged over the years. These other approaches require advanced skills of the operators and a multidisciplinary team with dedicated physicians. Another important part of the management of vascular access is the closure systems used for hemostasis. Currently, two types of devices are typically used in the lab: suture-based or plug-based ones. In this review we want to describe all these aspects related to the management of vascular access in pMCS and describe, finally, a case report from our center's experience.

Novel Technique to Fenestrate an Aortic Dissection Flap using Electrocautery

Chronic distal thoracic dissections treated with thoracic endovascular repair are prone to type Ib false lumen perfusion. When the supraceliac aorta is of normal caliber, fenestration of the dissection flap proximal to the visceral vessels creates a seal zone for the thoracic stent graft and eliminates the type Ib false lumen perfusion. We describe a novel way of crossing the septum using electrocautery delivered through a wire tip then fenestrating the septum using electrocautery delivered over a 1-mm area of uninsulated wire to cut the septum. We believe the use of electrocautery creates a controlled and deliberate aortic fenestration during endovascular repair of a distal thoracic dissections.

Feasibility of transcaval access TAVI in morbidly obese patients: A single-center experience

OBJECTIVES

We report a single-center experience in utilizing the transcaval-access transcatheter aortic valve implantation (TAVI) as an alternative approach in morbidly obese patients.

BACKGROUND

Morbidly obese patients present frequently for TAVI. Transfemoral arterial access TAVI in these patients is technically challenging due to deep arterial access, resulting in a higher risk of vascular complications. Transcaval access TAVI is increasingly used in patients with prohibitive iliofemoral arterial access.

METHODS

We used the transcaval approach for eight morbidly obese patients who had otherwise technically feasible femoral arterial access. This technique provides an alternative arterial access point that potentially circumvents some of the challenges relating to femoral arterial access.

RESULTS

We report eight morbidly obese patients with a mean body mass index of 42.3 ± 6.2 kg/m² who underwent transcaval access TAVI at our center (mean EuroScore II 2.47 ± 1.83%). The patient mean age was 70.3 ± 9.8 years; six were female. All eight patients underwent a successful and uncomplicated procedure. The median time to discharge was 2 days and all patients were alive at 30 days.

CONCLUSIONS

Transcaval access TAVI is a feasible alternative for morbidly obese patients and may reduce vascular complications. Further data are required to evaluate the safety of this approach.

A 20-year journey in transcatheter aortic valve implantation: Evolution to current eminence

Since the first groundbreaking procedure in 2002, transcatheter aortic valve implantation (TAVI) has revolutionized the management of aortic stenosis (AS). Through striking developments in pertinent equipment and techniques, TAVI has now become the leading therapeutic strategy for aortic valve replacement in patients with severe symptomatic AS. The procedure streamlining from routine use of conscious sedation to a single arterial access approach, the newly adapted implantation techniques, and the introduction of novel technologies such as intravascular lithotripsy and the refinement of valve-bioprosthesis devices along with the accumulating experience have resulted in a dramatic reduction of complications and have improved associated outcomes that are now considered comparable or even superior to surgical aortic valve replacement (SAVR). These advances have opened the road to the use of TAVI in younger and lower-risk patients and up-to-date data from landmark studies have now established the outstanding efficacy and safety of TAVI in patients with low-surgical risk impelling the most recent ESC guidelines to propose TAVI, as the main therapeutic strategy for patients with AS aged 75 years or older. In this article, we aim to summarize the most recent advances and the current clinical aspects involving the use of TAVI, and we also attempt to highlight impending concerns that need to be further addressed.

From an Unfolding Emergency Treatment to a Universal Shift in Therapy: The History and Evolution of the Catheter-Based Treatment of Aortic Valve Stenosis

Aortic valve stenosis (AVS) is the most frequent valvular heart disease in industrialized countries, presenting with very high mortality if left untreated. While drug treatment can sometimes alleviate symptoms, it fails to stop progression or cure the underlying disease. Until the first decade of this millennium, surgical aortic valve replacement (SAVR) remained the only available therapy option with a positive impact on mortality and morbidity. Even though several studies reported highly positive effects of SAVR regarding the improved quality of life and better physical performance, SAVR remained an intervention that, due to its remarkable complexity and the need for heart-lung machine and cardioplegia, was limited by the patients' comorbid profile. While unsatisfying hemodynamic results after transcatheter aortic balloon valvuloplasty in high-risk surgical patients limited its adoption as an alternative treatment, it provided the impetus for further interventional approaches to the therapy of AVS. This review considers the invention and development of transcatheter aortic valve implantation (TAVI), which established itself as a catheter-based, minimally invasive procedure over the past decade, and has become an equivalent treatment method for high-risk surgical patients. For that matter, early TAVI concepts, their amendments, and the associated pioneers are recognized for paving the way to a revolutionary diversification in AVS treatment.

The Role of Transcatheter Aortic Valve Replacement in Asymptomatic Aortic Stenosis: A Feasibility Analysis

Surgical aortic valve replacement (SAVR) is the current treatment of choice for good surgical candidates with moderate to severe symptomatic aortic stenosis (AS). As transcatheter aortic valvular replacement (TAVR) has shown an improved one and two-year all-cause mortality, it has been chosen for moderately symptomatic severe AS patients. The purpose of this review was to perform a clinical comparison of TAVR vs. SAVR and to analyze the Health Index Factor (HIF) that makes TAVR a treatment of choice in asymptomatic AS patients. 

An extensive literature search of PubMed, Cochrane, and Embase databases was performed using the keywords “Aortic stenosis”, “SAVR”, “TAVR”, and “Asymptomatic”. A total of 45 prospective randomized clinical trials in the English language that were published from the year 2000 onwards were included in the final analysis. It has been found that 59.3% of asymptomatic AS patients are likely to die in the next five years without proactive treatment. Multiple studies have proven that early intervention with aortic valve replacement is superior to conservative treatment in severe asymptomatic AS; however, the choice between SAVR and TAVR is not well established. The NOTION Trial, SURTAVI Trail, and PARTNER 3 study have shown the non-inferiority of TAVR over SAVR, during one-year follow-up for low surgical risk patients. Evolut Low-Risk study and Early TAVR are the only two prospective studies performed to date that have enrolled patients with asymptomatic severe AS. The Evolut Trial demonstrated no difference in all-cause mortality at 30 days (1.3% vs. 4.8%. p=0.23), and 12 days (1.3% vs. 6.5%, p=0.11). Additionally, TAVR also decreases the risk of post-procedural atrial fibrillation, acute kidney injury (AKI), and rehospitalization, and leads to significant improvement in the mean trans-aortic pressure gradient. TAVR also showed marked improvement in the 30-day Quality of Life (QOL) index, where SAVR did not report any significant change in the QOL index. However, the official recommendations of Early TAVR are still awaited. TAVR has consistently shown a statistically non-significant difference in case mortality, risk of stroke, and rehospitalization with moderate to high surgical risk patients whereby recent initial trials have shown significant improvement in the QOL index and hemodynamic index for patients with asymptomatic disease. More extensive studies are required to prove the risk stratifications, long-term outcomes, and clinical characteristics that would make TAVR a preferred intervention in asymptomatic patients.

Advances in technology and techniques for transcatheter aortic valve replacement with concomitant peripheral arterial disease

Aortic stenosis (AS) is a prevalent disease affecting 3.7% of the adult population aged 65 or above. In the past, surgical aortic valve replacement (SAVR) was the only definitive therapy available for the treatment of severe AS. Owing to the invasive nature of open-heart surgery, patients with advanced age and frailty could not benefit from SAVR. The advent of transcatheter aortic valve replacement (TAVR) in the past decade has offered an alternative treatment option for patients with severe AS, particularly those who are deemed to have high surgical risks. Nevertheless, a large proportion of patients also have concomitant peripheral arterial disease (PAD), which increases the risk of peri-procedural vascular complication, and precludes the possibility of transfemoral TAVR owing to inadequate luminal size for delivery system deployment. In this review, the prevalence and outcome of TAVR patients with PAD will be discussed. Furthermore, novel technologies and techniques that enable TAVR to be safely performed using transfemoral or alternative access in patients with severe PAD will be reviewed.

Long Term Monitoring of Thoracic Endovascular Aortic Aneurysm Repair Using Transcaval Aortic Access

Thoracic endovascular aortic repair (TEVAR) has reduced the morbidity and mortality associated with the treatment of thoracic aortic pathologies. However, TEVAR's use is often predicated on sufficiently large femoral access for the delivery of the endograft device. Transcaval access, or the delivery of endovascular device via the vena cava before crossing into the aorta, has been used successfully for the deployment of transcatheter aortic valves. Our institution previously reported on a case of TEVAR using transcaval access. We now report on the long-term follow-up outcome of this case. At 6 years post-surgery, computed tomography angiography (CTA) indicates stable aortic repair without any concerning findings associated with the site of transcaval access into the aorta. The patient is clinically without signs of lower extremity vascular or cardiopulmonary compromise. Overall, transcaval access for TEVAR is a promising alternative to traditional femoral artery access in highly-select patients with the appropriate anatomical and pathological indications.

Not all pseudoaneurysms are femoral-A transcaval transcatheter aortic valve replacement rare complication

We report a case of a 73-year-old male with multiple comorbidities, including postpoliomyelitis severe scoliosis, referred to our tertiary center due to a severe symptomatic aortic stenosis, considered high risk for surgical aortic valve replacement (AVR). Due to unsuitable femoral and subclavian accesses, the patient underwent a transcaval transcatheter AVR (TAVR) procedure, complicated by the development of an iatrogenic infrarenal aortic pseudoaneurysm with aortocaval fistula. Scoliosis can cause varying anatomic relationships between retroperitoneal vessels and intervertebral disk spaces, which increase the difficulty of the procedure and consequently lead to this vascular complication. Although most aortocaval fistulas close spontaneously after 1 year, the risk of pseudoaneurysm rupture in this critical area was crucial in the decision of a new successful percutaneous aortic stent intervention.

Transcatheter Aortic Valve Implantation: All Transfemoral? Update on Peripheral Vascular Access and Closure

Transfemoral access remains the most widely used peripheral vascular approach for transcatheter aortic valve implantation (TAVI). Despite technical improvement and reduction in delivery sheath diameters of all TAVI platforms, 10-20% of patients remain not eligible to transfemoral TAVI due to peripheral artery disease. In this review, we aim at presenting an update of recent data concerning transfemoral access and percutaneous closure devices. Moreover, we will review peripheral non-transfemoral alternative as well as caval-aortic accesses and discuss the important features to assess with pre-procedural imaging modalities before TAVI.

Clinical Outcome and Safety of Transcaval Access for Transcatheter Aortic Valve Replacement as Compared to Other Alternative Approaches

Background: A small proportion of patients in need of transcatheter aortic valve replacement (TAVR) are not suitable for the transfemoral approach due to peripheral artery disease. Alternative TAVR approaches are associated with short- and long-term hazards. A novel technique of caval-aortic (transcaval) access for TAVR has been utilized as an alternative access technique.

Aim: To compare safety and efficacy of transcaval access as compared to other alternative access (axillary or apical) for TAVR.

Methods: A single-center, retrospective analysis of consecutive patients undergoing alternative access for TAVR. Events were adjudicated according to VARC-2 criteria.

Results: A total of 185 patients were included in the present analysis. Mean age was 81 years with a small majority for male gender (54%). Of the entire cohort, 20 patients (12%) underwent transcaval TAVR, and 165 patients (82%) underwent TAVR using alternative access. Overall, baseline characteristics were comparable between the two groups. General anesthesia was not utilized in transcaval patients; however, it was routinely used in nearly all alternative access patients. TAVR device success was comparable between the two groups (95%). Acute kidney injury occurred significantly less frequently among transcaval patients as compared to alternative access patients (5 vs. 12%, p = 0.05). Hospital stay was shorter for transcaval patients (6.3 days vs. 14.4; p < 0.001). No difference in early or 30-day mortality (10 vs. 7.9%, p = 0.74) was noted between groups.

Conclusions: In patients who cannot undergo TAVR via the trans-femoral approach due to peripheral vascular disease, transcaval access is a safe approach as compared to other alternative access techniques, with lower risk of kidney injury and shorter hospital stay.

Alternative Access for Transcatheter Aortic Valve Replacement: A Comprehensive Review

Transfemoral is the most widely used access to perform transcatheter aortic valve replacement (TAVR). However, alternative access is needed in up to 21% of patients with TAVR because of a myriad of factors. The authors provide a comprehensive review on alternative access for TAVR, discussing the relevant data and providing the pros and cons of each access route.

Pushing the limits for interventional treatment of aortic valve stenosis

As we approach 20 years of clinical experience with transcatheter aortic valve replacement (TAVR), a vast portfolio of high-quality clinical data has accumulated, confirming the safety and efficacy of TAVR across the entire spectrum of surgical risk. Although many aspects of this innovative therapy have been thoroughly studied, several challenges remain. As TAVR is expanding to include younger low-risk patients, with longer life expectancy, one major unsolved issue is represented by transcatheter heart valve (THV) durability, since robust THV durability data are currently limited to approximately 5-6 years. Additionally, steric interactions between THV components and coronary ostia may render coronary access particularly difficult, and thus personalized decisions regarding THV type and implanting techniques are of paramount importance to secure future coronary access. Since bicuspid aortic valve (BAV) stenosis may be associated with unfavorable anatomic factors, it has represented an exclusion criterion in major randomized TAVR trials. Albeit promising data are available from multicenter registries, results of specifically designed randomized trials are eagerly needed to inform use of TAVR for BAV stenosis. Although valve-in-valve (ViV) TAVR has emerged as an effective treatment option for degenerated aortic bioprostheses, ViV procedures are associated with specific risks, which mandated the development of specific techniques aimed at reducing the occurrence of periprocedural adverse events. Despite the transfemoral approach represents the access of choice for TAVR, a significant proportion of patients have significant peripheral artery disease and alternative vascular access routes have been increasingly evaluated with encouraging data regarding their safety and feasibility.

Valve Academic Research Consortium 3: updated endpoint definitions for aortic valve clinical research

Aims 

The Valve Academic Research Consortium (VARC), founded in 2010, was intended to (i) identify appropriate clinical endpoints and (ii) standardize definitions of these endpoints for transcatheter and surgical aortic valve clinical trials. Rapid evolution of the field, including the emergence of new complications, expanding clinical indications, and novel therapy strategies have mandated further refinement and expansion of these definitions to ensure clinical relevance. This document provides an update of the most appropriate clinical endpoint definitions to be used in the conduct of transcatheter and surgical aortic valve clinical research.

Methods and results 

Several years after the publication of the VARC-2 manuscript, an in-person meeting was held involving over 50 independent clinical experts representing several professional societies, academic research organizations, the US Food and Drug Administration (FDA), and industry representatives to (i) evaluate utilization of VARC endpoint definitions in clinical research, (ii) discuss the scope of this focused update, and (iii) review and revise specific clinical endpoint definitions. A writing committee of independent experts was convened and subsequently met to further address outstanding issues. There were ongoing discussions with FDA and many experts to develop a new classification schema for bioprosthetic valve dysfunction and failure. Overall, this multi-disciplinary process has resulted in important recommendations for data reporting, clinical research methods, and updated endpoint definitions. New definitions or modifications of existing definitions are being proposed for repeat hospitalizations, access site-related complications, bleeding events, conduction disturbances, cardiac structural complications, and bioprosthetic valve dysfunction and failure (including valve leaflet thickening and thrombosis). A more granular 5-class grading scheme for paravalvular regurgitation (PVR) is being proposed to help refine the assessment of PVR. Finally, more specific recommendations on quality-of-life assessments have been included, which have been targeted to specific clinical study designs.

Conclusions 

Acknowledging the dynamic and evolving nature of less-invasive aortic valve therapies, further refinements of clinical research processes are required. The adoption of these updated and newly proposed VARC-3 endpoints and definitions will ensure homogenous event reporting, accurate adjudication, and appropriate comparisons of clinical research studies involving devices and new therapeutic strategies.

Valve Academic Research Consortium 3: Updated Endpoint Definitions for Aortic Valve Clinical Research

AIMS

The Valve Academic Research Consortium (VARC), founded in 2010, was intended to (i) identify appropriate clinical endpoints and (ii) standardize definitions of these endpoints for transcatheter and surgical aortic valve clinical trials. Rapid evolution of the field, including the emergence of new complications, expanding clinical indications, and novel therapy strategies have mandated further refinement and expansion of these definitions to ensure clinical relevance. This document provides an update of the most appropriate clinical endpoint definitions to be used in the conduct of transcatheter and surgical aortic valve clinical research.

METHODS AND RESULTS

Several years after the publication of the VARC-2 manuscript, an in-person meeting was held involving over 50 independent clinical experts representing several professional societies, academic research organizations, the US Food and Drug Administration (FDA), and industry representatives to (i) evaluate utilization of VARC endpoint definitions in clinical research, (ii) discuss the scope of this focused update, and (iii) review and revise specific clinical endpoint definitions. A writing committee of independent experts was convened and subsequently met to further address outstanding issues. There were ongoing discussions with FDA and many experts to develop a new classification schema for bioprosthetic valve dysfunction and failure. Overall, this multi-disciplinary process has resulted in important recommendations for data reporting, clinical research methods, and updated endpoint definitions. New definitions or modifications of existing definitions are being proposed for repeat hospitalizations, access site-related complications, bleeding events, conduction disturbances, cardiac structural complications, and bioprosthetic valve dysfunction and failure (including valve leaflet thickening and thrombosis). A more granular 5-class grading scheme for paravalvular regurgitation (PVR) is being proposed to help refine the assessment of PVR. Finally, more specific recommendations on quality-of-life assessments have been included, which have been targeted to specific clinical study designs.

CONCLUSIONS

Acknowledging the dynamic and evolving nature of less-invasive aortic valve therapies, further refinements of clinical research processes are required. The adoption of these updated and newly proposed VARC-3 endpoints and definitions will ensure homogenous event reporting, accurate adjudication, and appropriate comparisons of clinical research studies involving devices and new therapeutic strategies.

Large Sheath Management in Patients with Poor Peripheral Access

Despite the evolution of device technology and increasing operator experience, vascular and bleeding complications remain a major source of perioperative morbidity and mortality, particularly in patients with peripheral arterial disease. These complications may be compounded with the use of large bore access sheaths for mechanical support, which may be required to be left in the vessels for a prolonged period of time. Through this article, the authors demonstrate the importance of assessment for peripheral arterial disease before insertion of large bore sheaths. They also describe various strategies to manage occlusive sheaths for distal reperfusion and percutaneous axillary artery access as an alternate option.

Current Trends in TAVI Access

The optimal approach for Transcatheter aortic valve implantation (TAVI) is the transfemoral access but alternative TAVI approaches offer the possibility of valve replacement in patients who are not eligible to the transfemoral route. This review paper intends to compare the current available alternative approaches for TAVI in terms of their safety and efficacy, based on the current literature. The transapical, transaortic, transsubclavian, transcarotid, transcaval and suprasternal approaches have been analyzed. The choice of the alternative approach dependents on local Heart Team expertise, patient specific characteristics, access specific characteristics and the need or not for general anesthesia. More studies are needed to investigate the impact of each individual approach on long-term outcomes.

Comparable Outcomes for Transcarotid and Transfemoral Transcatheter Aortic Valve Replacement at a High Volume US Center

With continued growth of transcatheter aortic valve replacement (TAVR), safe alternative access remains important for patients without adequate transfemoral (TF) access. Registry-based outcomes with transcarotid (TC) TAVR are favorable compared to transapical or transaxillary/subclavian, but TC vs TF comparisons have not been made. Our objective was to compare outcomes between TF and TC access routes for TAVR at a high-volume United States center. Methods: We retrospectively evaluated all TF and TC TAVR procedures from June 11, 2014 (first TC case) through December 31, 2019. The primary outcomes were 30-day stroke and 30-day mortality. Secondary outcomes were 1-year stroke, 1-year survival, and 30-day and 1-year life-threatening/major bleeding, vascular complications, and myocardial infarction. Propensity score weighted (PSW) models were used to compare risk-adjusted TF and TC outcomes. Of 1,465 TAVR procedures, 1319 (90%) were TF and 146 (10%) were TC. Procedure time and length of stay did not differ between groups. Unadjusted 30-day stroke (TF = 2.0%, TC = 2.7%, P = 0.536) and mortality (TF = 2.1%, TC = 2.7%, P = 0.629) were similar between groups. PSW 30-day stroke (odds ratio (OR) (95% confidence interval (CI)) = 0.8 (0.2-2.8)) and mortality (OR (95% CI) = 0.8 (0.2-3.0)) were similar between groups. Unadjusted and PSW 30-day major/life threatening bleeding, major vascular complications, and myocardial infarction did not differ between groups. Survival at one year was 90% (88%-92%) for TF patients and 87% (81%-93%) for TC patients (unadjusted P = 0.28, PSW hazard ratio = 1.0 (0.6-1.7)). Transcarotid TAVR is associated with similar outcomes compared to transfemoral TAVR at an experienced, high-volume center.

Alternative Access for Mechanical Circulatory Support

Femoral arterial access is the default strategy for large-bore interventional procedures, including temporary mechanical circulatory support implantation and structural heart therapies, based on superior outcomes and operator ease. In addition to patient size and comorbidities, vessel tortuosity, significant calcification, and diminutive vessel caliber all may make iliofemoral access prohibitively high risk or impossible. Given the increase of large-bore transcatheter procedures, bleeding avoidance strategies are essential and thus novel mechanisms for large-bore access have evolved. This article highlights the advantages, limitations, and practical approaches to the 2 most common percutaneous large-bore alternative access strategies: transaxillary and transcaval access.

Transcaval aortic valve implantation in a patient with Larsen syndrome: technical and anesthetic challenges

Transcatheter aortic valve implantation has emerged as a therapeutic option for patients with symptomatic severe aortic stenosis who are inoperable, or at very high risk of open-heart surgery. Recently, we encountered a patient with aortic stenosis and Larsen syndrome, who had short stature, obesity, kyphoscoliosis, multiple musculoskeletal deformities, and severe restrictive lung disease. An open-heart surgery in such a patient involves substantial peri-operative risk. A successful transcaval aortic valve implantation was done under general anesthesia.

Comparison of Deep Sedation and General Anesthesia With an Endotracheal Tube for Transcaval Transcatheter Aortic Valve Replacement: A Pioneering Institution's Experience

OBJECTIVES

Transcaval transcatheter aortic valve replacement (TC-TAVR) is an alternative approach to transcatheter aortic valve replacement involving deployment of the bioprosthetic valve via a conduit created from the inferior vena cava to the descending aorta in patients for whom the traditional transfemoral approach is not feasible. By analyzing the largest known cohort of TC-TAVR patients, the authors wished to compare hospital length of stay and post-procedure outcomes between patients who underwent the procedure under deep sedation (DS) and patients who underwent general anesthesia with an endotracheal tube.

DESIGN

Retrospective, single-center study.

SETTING

Henry Ford Hospital in Detroit, MI.

PARTICIPANTS

Patients undergoing TC-TAVR from 2015 to 2018.

MEASUREMENTS AND MAIN RESULTS

Seventy-nine patients were included in the analysis, which consisted of 38 under general anesthesia with an endotracheal tube and 41 under DS. The sample was divided into a general anesthesia (GA) group and DS group. There were no significant differences in implant success rate or post-procedure outcomes, including in-hospital mortality (p = 0.999) and major vascular complication rate (p = 0.481), between the two groups. Patients in the GA group stayed a median of 24 hours longer in the intensive care unit (ICU) (p < 0.001) and one day longer in the hospital (p = 0.046) after the procedure compared to patients in the DS group. The median procedure time was significantly lower (135 minutes) in the DS group compared to the GA group (167 minutes, p < 0.001).

CONCLUSIONS

Patients undergoing TC-TAVR under DS had similar postoperative outcomes and shorter post-procedure hospital and ICU lengths of stay compared to general anesthesia. In the authors' experience, DS is the preferred anesthetic technique for TC-TAVR.

Transcaval Access to the Abdominal Aorta: indications of Interest to Surgeons and a Comprehensive Literature Review

We performed a review of the literature (until August 01, 2019) on the occasion of the first transcaval approach for transcatheter aortic valve implantation in our hospital. This review focuses mainly on the indications of this alternative access route to the aorta. It may be useful for vascular surgeons in selected cases, such as the treatment of endoleaks after endovascular aneurysm repair and thoracic endovascular aneurysm repair. We describe historical aspects of transcaval access to the aorta, experimental studies, available case series and outcomes. Finally, we summarize the most significant technical aspects of this little-known access.

Percutaneous Endovascular Aneurysm Repair: Current Status and Future Trends

Endovascular aneurysm repair (EVAR) is a common, safe, and effective method of treating abdominal aortic aneurysms. Traditionally treated via surgical cutdown over the common femoral arteries, many recent studies demonstrate percutaneous access techniques to avoid the surgical cutdown. Developing familiarity with these percutaneous techniques, including risks, complications, adjuncts, and alternative accesses, can help improve the outcomes and availability of EVAR. As these techniques become increasingly common, it is not unlikely that they can be practiced safely in select patients in an outpatient setting.

Transcaval access for the emergency delivery of 5.0 liters per minute mechanical circulatory support in cardiogenic shock

OBJECTIVES

The purpose of this study was to describe the feasibility and early outcomes of transcaval access for delivery of emergency mechanical circulatory support (MCS) in cardiogenic shock.

BACKGROUND

Vascular access for implantation of MCS in patients with cardiogenic shock is often challenging due to peripheral arterial disease and vasoconstriction. Transcaval delivery of MCS may be an alternative. We describe a series of patients we implanted an Impella 5.0 device, on-table without CT planning, through a percutaneous transcaval access route.

METHODS

Ten patients with progressive or refractory cardiogenic shock underwent Impella 5.0 implantation via transcaval access. Demographic, clinical and procedural variables and in-hospital outcomes were collected.

RESULTS

All ten underwent emergency implantation of the 7 mm diameter Impella 5.0 device via transcaval access. Six were women, with median age of 55.5 years (range, 29-69). Cardiogenic shock was attributed to idiopathic nonischemic cardiomyopathy (n = 4), myocarditis (n = 2), ischemic cardiomyopathy (n = 2), heart transplant rejection (n = 1), and unknown etiology (n = 1). Median duration of support was 92.1 hr (range, 21.2-165.4). Seven (70%) survived to device explant, with six (60%) surviving to access port closure and discharge. Among survivors, five recovered heart function and one received destination therapy left ventricular assist device.

CONCLUSIONS

Transcaval access is feasible for emergency nonsurgical implantation of the Impella 5.0 device in cardiogenic shock with small or diseased iliofemoral arteries. This allows early institution of higher-flow MCS than conventional femoral artery implantation of the 3.5 L Impella CP device, and enables a bridge-to-recovery or bridge-to-destination strategy.

Alcohol Septal Ablation to Prevent Left Ventricular Outflow Tract Obstruction During Transcatheter Mitral Valve Replacement: First-in-Man Study

OBJECTIVES

This study evaluates outcomes of pre-emptive alcohol septal ablation (ASA) to prevent iatrogenic left ventricular outflow tract (LVOT) obstruction after transcatheter mitral valve replacement (TMVR).

BACKGROUND

LVOT obstruction is a life-threatening complication of TMVR. Bail-out ASA has been described as a therapeutic option for patients with outflow obstruction during TMVR, but little is known about pre-emptive ASA.

METHODS

Multicenter registry of patients with severe mitral valve disease who underwent pre-emptive ASA to mitigate LVOT obstruction risk after TMVR. High risk of LVOT obstruction was predicted in all patients by pre-procedural computed tomographic imaging.

RESULTS

Thirty patients (age 76.1 ± 7.7 years; women 76.7%) with severe mitral valve disease underwent pre-emptive ASA to mitigate TMVR-induced LVOT obstruction risk. Twenty patients underwent mitral valve replacement (14 transseptal, 3 transatrial, 1 transapical, 1 transseptal with percutaneous laceration of anterior mitral leaflet, 1 treated with surgical mitral valve replacement). Eight patients experienced clinical improvement post-ASA. Two patients died before TMVR. Median increase in neo-LVOT surface area post-ASA was 111.2 mm² (interquartile range: 71.4 to 193.1 mm²). Five patients (16.7%) required pacemaker implantation post-ASA. In-hospital and 30-day mortality post-ASA was 6.7% (2/30 patients). After ASA, TMVR was performed successfully in 100% of attempted cases. In-hospital and 30-day mortality post-TMVR was 5.3% (1/19). Mortality of entire cohort was 10% (3/30 patients: 2 post-ASA before TMVR, 1 died 30 days post-TMVR).

CONCLUSIONS

Pre-emptive ASA is associated with a significant increase in predicted neo-LVOT area before TMVR and may enable safe TMVR in patients usually excluded secondary to prohibitive risk of LVOT obstruction.

The evolving role of interventional cardiology in the treatment of pulmonary hypertension

Pulmonary hypertension (PH) is a heterogeneous group of diseases defined by a mean pulmonary arterial pressure greater than 20 mmHg. Clinically, PH is classified into five groups and the group of PH generally defines the cause of PH and the therapeutic options. Currently, medical therapies that target the prostacyclin, endothelin, and nitric oxide pathways are used in pulmonary arterial hypertension and chronic thromboembolic PH (CTEPH) patients. Moreover, surgery can improve outcomes in PH as pulmonary thromboendarterectomy can be curative for CTEPH and lung transplantation is used for end-stage PH. Despite these diverse treatment options, PH patients continue to have high symptom burden and poor long-term outcomes. However, advances in percutaneous technology are opening new avenues for the management of PH. In this review, we discuss the available data supporting the use of four interventional procedures: balloon atrial septostomy, transcatheter Potts shunt, balloon pulmonary angioplasty, and pulmonary artery denervation for the treatment of PH. These procedures provide hemodynamic and functional improvements in PH patients, but they come with their own unique risk profiles. Hopefully, these procedures will continue to be refined and thereby provide a venue for interventional cardiology to safely and effectively improve outcomes for PH moving forward.

The Fate of Transcaval Access Tracts: 12-Month Results of the Prospective NHLBI Transcaval Transcatheter Aortic Valve Replacement Study

OBJECTIVES

The authors investigated 1-year outcomes after transcaval access and closure for transcatheter aortic valve replacement (TAVR), using commercially available nitinol cardiac occluders off-label.

BACKGROUND

Transcaval access is a fully percutaneous nonfemoral artery route for TAVR. The intermediate-term fate of transcaval access tracts is not known.

METHODS

The authors performed a prospective, multicenter, independently adjudicated trial of transcaval access, using Amplatzer nitinol cardiac occluders (Abbott Vascular, Minneapolis, Minnesota), among subjects without traditional transthoracic (transapical or transaortic) access options. One-year clinical follow-up included core laboratory analysis of serial abdominal computed tomography (CT).

RESULTS

100 subjects were enrolled. Twelve-month mortality was 29%. After discharge, there were no vascular complications of transcaval access. Among 83 evaluable CT scans after 12 months, 77 of fistulas (93%) were proven occluded, and only 1 was proven patent. Fistula patency was not associated with overall survival (p = 0.37), nor with heart failure admissions (15% if patent vs. 23% if occluded; p = 0.30). There were no cases of occluder fracture or migration or visceral injury.

CONCLUSIONS

Results are reassuring 1 year after transcaval TAVR and closure using permeable nitinol occluders off-label. There were no late major vascular complications. CT demonstrated spontaneous closure of almost all fistulas. Results may be different in a lower-risk cohort, with increased operator experience, and using a dedicated transcaval closure device. (Transcaval Access for Transcatheter Aortic Valve Replacement in People With No Good Options for Aortic Access; NCT02280824).

Transcatheter Electrosurgery: JACC State-of-the-Art Review

Transcatheter electrosurgery refers to a family of procedures using radiofrequency energy to vaporize and traverse or lacerate tissue despite flowing blood. The authors review theory, simulations, and benchtop demonstrations of how guidewires, insulation, adjunctive catheters, and dielectric medium interact. For tissue traversal, all but the tip of traversing guidewires is insulated to concentrate current. For leaflet laceration, the "Flying V" configuration concentrates current at the inner lacerating surface of a kinked guidewire. Flooding the field with non-ionic dextrose eliminates alternative current paths. Clinical applications include traversing occlusions (pulmonary atresia, arterial and venous occlusion, and iatrogenic graft occlusion), traversing tissue planes (atrial and ventricular septal puncture, radiofrequency valve repair, transcaval access, Potts and Glenn shunts), and leaflet laceration (BASILICA, LAMPOON, ELASTA-Clip, and others). Tips are provided for optimizing these techniques. Transcatheter electrosurgery already enables a range of novel therapeutic procedures for structural heart disease, and represents a promising advance toward transcatheter surgery.