Future perspectives in transcatheter aortic valve implantation

Transcatheter aortic valve replacement (TAVR) constitutes a relatively new treatment option for the patients with severe symptomatic aortic stenosis. Evidence from registries and randomized control trials has underscored the value of this treatment in inoperable and high risk populations, while new developments in valve technology and TAVR enabling devices have reduced the risk of complications, simplified the procedure, and broadened the applications of this therapy. The initial promising clinical results and the potential of an effective less invasive treatment of aortic stenosis has not only created high expectations but also the need to address the pitfalls of TAVR technology. The evolving knowledge concerning the groups of patients who would benefit from this treatment, the limited long term follow-up data, the concerns about devices' long term durability, and the severity of complications remain important caveats which restrict the widespread clinical adoption of TAVR. The aim of this review article is to present the recent advances, highlight the limitations of TAVR technology, and discuss the future perspectives in this rapidly evolving field.

The 2011-12 pilot European Sentinel Registry of Transcatheter Aortic Valve Implantation: in-hospital results in 4,571 patients

AIMS The aim of this prospective multinational registry is to assess and identify predictors of in-hospital outcome and complications of contemporary TAVI practice. METHODS AND RESULTS The Transcatheter Valve Treatment Sentinel Pilot Registry is a prospective independent consecutive collection of individual patient data entered into a web-based case record form (CRF) or transferred from compatible national registries. A total of 4,571 patients underwent TAVI between January 2011 and May 2012 in 137 centres of 10 European countries. Average age was 81.4±7.1 years with equal representation of the two sexes. Logistic EuroSCORE (20.2±13.3), access site (femoral approach: 74.2%), type of anaesthesia and duration of hospital stay (9.3±8.1 days) showed wide variations among the participating countries. In-hospital mortality (7.4%), stroke (1.8%), myocardial infarction (0.9%), major vascular complications (3.1%) were similar in the SAPIEN XT and CoreValve (p=0.15). Mortality was lower in transfemoral (5.9%) than in transapical (12.8%) and other access routes (9.7%; p<0.01). Advanced age, high logistic EuroSCORE, pre-procedural ≥grade 2 mitral regurgitation and deployment failure predicted higher mortality at multivariate analysis. CONCLUSIONS Increased operator experience and the refinement of valve types and delivery catheters may explain the lower rate of mortality, stroke and vascular complications than in historical studies and registries.

Transcatheter aortic valve implantation and bleeding: incidence, predictors and prognosis

Peri-procedural bleeding complications are feared adverse events in patients undergoing transcatheter aortic valve implantation (TAVI). Little is known about the implications of peri-procedural bleeding on clinical outcome. In a prospective single-center registry of consecutive patients undergoing TAVI, we investigated incidence, predictors and clinical consequences of life-threatening and major bleeding as defined by the Valve Academic Research Consortium. Among 389 consecutive patients undergoing TAVI by a transfemoral (79.2%), transapical (19.6%) or trans-subclavian (1.3%) approach between July 2007 and October 2011, life-threatening or major peri-procedural bleeding events occurred in 64 (16.4%) and 125 patients (32.1%), respectively. Patients with peri-procedural bleeding events had a higher logistic EuroSCORE, more advanced renal disease, and were more symptomatic as assessed by New York Heart Association functional class at baseline as compared to patients with no bleeding. Life-threatening bleeding was associated with a higher all-cause (17.2 vs. 5.6 vs. 3.0%, p < 0.001) and cardiovascular mortality (10.9 vs. 5.6 vs. 2.5%, p = 0.02) at 30 days compared to patients with major bleeding or no bleeding. Multivariate analysis identified transapical access (OR 2.6, 95% CI 1.4-4.8; p = 0.002), glomerular filtration rate <30 ml/min (OR 2.3, 95% CI 1.1-4.7, p = 0.031), and diabetes (OR 1.8, 95% CI 1.001-3.2, p = 0.049) as independent predictors of life-threatening, peri-procedural bleeding. Life-threatening bleeding complications in patients undergoing TAVI are associated with increased mortality. Renal impairment, diabetes, and transapical approach were identified as independent risk factors for life-threatening bleeding events.

Accuracy and reproducibility of aortic annulus sizing using a dedicated three-dimensional computed tomography reconstruction tool in patients evaluated for transcatheter aortic valve replacement

Aims: To evaluate the accuracy and reproducibility of aortic annulus sizing using a multislice computed tomography (MSCT) based aortic root reconstruction tool compared with conventional imaging among patients evaluated for transcatheter aortic valve replacement (TAVR). Methods and results: Patients referred for TAVR underwent standard preprocedural assessment of aortic annulus parameters using MSCT, angiography and transoesophageal echocardiography (TEE). Three-dimensional (3-D) reconstruction of MSCT images of the aortic root was performed using 3mensio (3mensio Medical Imaging BV, Bilthoven, The Netherlands), allowing for semi-automated delineation of the annular plane and assessment of annulus perimeter, area, maximum, minimum and virtual diameters derived from area and perimeter (aVD and pVD). A total of 177 patients were enrolled. We observed a good inter-observer variability of 3-D reconstruction assessments with concordance coefficients for agreement of 0.91 (95% CI: 0.87-0.93) and 0.91 (0.88-0.94) for annulus perimeter and area assessments, respectively. 3-D derived pVD and aVD correlated very closely with a concordance coefficient of 0.97 (0.96-0.98) with a mean difference of 0.5±0.3 mm (pVD-aVD). 3-D derived pVD showed the best, but moderate concordance with diameters obtained from coronal MSCT (0.67, 0.56-0.75; 0.3±1.8 mm), and the lowest concordance with diameters obtained from TEE (0.42, 0.31-0.52; 1.9±1.9 mm). Conclusions: MSCT-based 3-D reconstruction of the aortic annulus using the 3mensio software enables accurate and reproducible assessment of aortic annulus dimensions.

Clinical outcomes of patients with low-flow, low-gradient, severe aortic stenosis and either preserved or reduced ejection fraction undergoing transcatheter aortic valve implantation

AIMS Our aim was to evaluate the invasive haemodynamic indices of high-risk symptomatic patients presenting with 'paradoxical' low-flow, low-gradient, severe aortic stenosis (AS) (PLF-LG) and low-flow, low-gradient severe AS (LEF-LG) and to compare clinical outcomes following transcatheter aortic valve implantation (TAVI) among these challenging AS subgroups. METHODS AND RESULTS Of 534 symptomatic patients undergoing TAVI, 385 had a full pre-procedural right and left heart catheterization. A total of 208 patients had high-gradient severe AS [HGAS; mean gradient (MG) ≥40 mmHg], 85 had PLF-LG [MG ≤ 40 mmHg, indexed aortic valve area [iAVA] ≤0.6 cm(2) m(-2), stroke volume index ≤35 mL/m(2), ejection fraction (EF) ≥50%], and 61 had LEF-LG (MG ≤ 40 mmHg, iAVA ≤0.6 cm(2) m(-2), EF ≤40%). Compared with HGAS, PLF-LG and LEF-LG had higher systemic vascular resistances (HGAS: 1912 ± 654 vs. PLF-LG 2006 ± 586 vs. LEF-LG 2216 ± 765 dyne s m(-5), P = 0.007) but lower valvulo-arterial impedances (HGAS: 7.8 ± 2.7 vs. PLF-LG 6.9 ± 1.9 vs. LEF-LG 7.7 ± 2.5 mmHg mL(-1) m(-2), P = 0.027). At 30 days, no differences in cardiac death (6.5 vs. 4.9 vs. 6.6%, P = 0.90) or death (8.4 vs. 6.1 vs. 6.6%, P = 0.88) were observed among HGAS, PLF-LG, and LEF-LG groups, respectively. At 1 year, New York Heart Association functional improvement occurred in most surviving patients (HGAS: 69.2% vs. PLF-LG 71.7% vs. LEF-LG 89.3%, P = 0.09) and no significant differences in overall mortality were observed (17.6 vs. 20.5 vs. 24.5%, P = 0.67). Compared with HGAS, LEF-LG had a higher 1 year cardiac mortality (adjusted hazard ratio 2.45, 95% confidence interval 1.04-5.75, P = 0.04). CONCLUSION TAVI in PLF-LG or LEF-LG patients is associated with overall mortality rates comparable with HGAS patients and all groups profit symptomatically to a similar extent.

Transcatheter aortic valve implantation: patient selection

Transcatheter aortic valve implantation (TAVI) is a disruptive technology as it satisfies a previously unmet need which is associated with a profound therapeutic benefit. In randomized clinical trials, TAVI has been shown to improve survival compared with medical treatment among patients considered not suitable candidates for surgical aortic valve replacement (SAVR), and to provide similar outcomes as SAVR in selected high-risk patients. Currently, TAVI is limited to selected elderly patients with symptomatic severe aortic stenosis. As this patient population frequently suffers from comorbid conditions, which may influence outcomes, the selection of patients to undergo TAVI underlies a complex decision process. Several clinical risk score algorithms are routinely used, although they fall short to fully appreciate the true risk among patients currently referred for TAVI. Beyond traditional risk scores, the clinical assessment by an interdisciplinary Heart Team as well as detailed imaging of the aortic valve, aortic root, descending and abdominal aorta as well as peripheral vasculature are important prerequisites to plan a successful procedure. This review will familiarize the reader with the concepts of the interdisciplinary Heart team, risk scores as well as the most important imaging algorithms suited to select appropriate TAVI patients.

Transcatheter aortic valve implantation: the transfemoral access route is the default access

Transcatheter aortic valve implantation (TAVI) is a widely accepted alternative to surgical aortic valve replacement (SAVR) among non-operable patients or selected high-risk patients with degenerative, severe aortic stenosis. TAVI is considered less invasive when compared with SAVR; however, there remain significant differences between different TAVI access routes. The transfemoral approach is considered the least invasive access route, and can be performed as a fully percutaneous procedure in a spontaneously breathing patient under local anaesthesia and mild sedation only. Moreover, transfemoral TAVI patients are typically transferred to coronary care rather than to an intensive care unit after the procedure, and benefit from early ambulation and a reduction in overall length of hospital stay. Considering these patient-specific and health-economic advantages, several TAVI centres follow the least invasive strategy for their patients and have implemented the transfemoral access route as the default access in their institutions. This article provides an overview on the prerequisites for a successful transfemoral TAVI procedure, describes the procedural advantages compared to alternative access routes, and highlights differences in clinical outcomes.

Increased vascularization during early healing after biologic augmentation in repair of chronic rotator cuff tears using autologous leukocyte- and platelet-rich fibrin (L-PRF): a prospective randomized controlled pilot trial

HYPOTHESIS We hypothesized that arthroscopic rotator cuff repairs using leukocyte- and platelet-rich fibrin (L-PRF) in a standardized, modified protocol is technically feasible and results in a higher vascularization response and watertight healing rate during early healing. METHODS Twenty patients with chronic rotator cuff tears were randomly assigned to 2 treatment groups. In the test group (N = 10), L-PRF was added in between the tendon and the bone during arthroscopic rotator cuff repair. The second group served as control (N = 10). They received the same arthroscopic treatment without the use of L-PRF. We used a double-row tension band technique. Clinical examinations including subjective shoulder value, visual analog scale, Constant, and Simple Shoulder Test scores and measurement of the vascularization with power Doppler ultrasonography were made at 6 and 12 weeks. RESULTS There have been no postoperative complications. At 6 and 12 weeks, there was no significant difference in the clinical scores between the test and the control groups. The mean vascularization index of the surgical tendon-to-bone insertions was always significantly higher in the L-PRF group than in the contralateral healthy shoulders at 6 and 12 weeks (P = .0001). Whereas the L-PRF group showed a higher vascularization compared with the control group at 6 weeks (P = .001), there was no difference after 12 weeks of follow-up (P = .889). Watertight healing was obtained in 89% of the repaired cuffs. DISCUSSION/CONCLUSIONS Arthroscopic rotator cuff repair with the application of L-PRF is technically feasible and yields higher early vascularization. Increased vascularization may potentially predispose to an increased and earlier cellular response and an increased healing rate.

Challenges and strategies in the repair of ruptured annulus fibrosus

Lumbar discectomy is the surgical procedure most frequently performed for patients suffering from low back pain and sciatica. Disc herniation as a consequence of degenerative or traumatic processes is commonly encountered as the underlying cause for the painful condition. While discectomy provides favourable outcome in a majority of cases, there are conditions where unmet requirements exist in terms of treatment, such as large disc protrusions with minimal disc degeneration; in these cases, the high rate of recurrent disc herniation after discectomy is a prevalent problem. An effective biological annular repair could improve the surgical outcome in patients with contained disc herniations but otherwise minor degenerative changes. An attractive approach is a tissue-engineered implant that will enable/stimulate the repair of the ruptured annulus. The strategy is to develop three-dimensional scaffolds and activate them by seeding cells or by incorporating molecular signals that enable new matrix synthesis at the defect site, while the biomaterial provides immediate closure of the defect and maintains the mechanical properties of the disc. This review is structured into (1) introduction, (2) clinical problems, current treatment options and needs, (3) biomechanical demands, (4) cellular and extracellular components, (5) biomaterials for delivery, scaffolding and support, (6) pre-clinical models for evaluation of newly developed cell- and material-based therapies, and (7) conclusions. This article highlights that an interdisciplinary approach is necessary for successful development of new clinical methods for annulus fibrosus repair. This will benefit from a close collaboration between research groups with expertise in all areas addressed in this review.

The medial based bi- or trilobed flap for repair of distal alar defects

BACKGROUND Reconstruction of defects of the lateral nasal ala might be challenging. Reconstruction with a bi- or trilobed flap is common. The laterally based bi- or trilobed flap for defects of the distal ala or lateral tip of the nose produces mostly tissue protrusion in the nasal groove which is aesthetically unpleasant. Why not use more the medially based bi- or trilobed flap? OBJECTIVE To describe the utility of bilobed and trilobed flaps for alar defects insisting on the design of medially based flaps. METHODS To show the technique and practical application for this kind of reconstruction. RESULTS The bi- and trilobed flaps are useful for defect repair between the lateral nasal tip and the distal ala. We observed that in most cases the flap based medially respects anatomical subunits better than the laterally based flap for medium-sized defects of the distal ala of the nose. CONCLUSION I suggest that the bi- and trilobed flaps for repair of the lateral tip/distal ala should more often be medially based. This flap has a specific indication and precise advantage compared to other reconstructions, especially to the laterally based multilobed flaps in this specific indication.

Emergency transcatheter aortic valve implantation for decompensated aortic stenosis

We report the case of an 84-year-old male presenting with syncope and dynamic ST-T wave changes due to decompensated severe valvular aortic stenosis undergoing successful emergency transcatheter aortic valve implantation.

Birhombic flap, a modified bilobed flap, for repair of nasal defect

BACKGROUND Reconstruction of longitudinal defects of the lateral nasal alar might be challenging. Reconstruction with a bilobed flap is common for round defects normally the bilobed flap is less suited for longitudinal defects. OBJECTIVE We describe a birhombic flap for longitudinal defect. METHODS Demonstration of the technique and practical application for this kind of reconstruction. RESULTS The bilobed flap is a very useful flap for lateral nasal tip or distal alar reconstruction. We show that a small modification of the flap allows to cover also longitudinal defects on the lateral tip of the nose. As the first lobe movement corresponds more to the rhomboid transposition flap, we prefer to call it birhombic flap. CONCLUSION The birhombic flap has its place in reconstructive surgery. This flap has a specific indication and precise advantages to other repairs in particular to the bilobed flap.