Dimitry Schewel

Direct Percutaneous Access Technique for Transaxillary Transcatheter Aortic Valve Implantation: “The Hamburg Sankt Georg Approach”

OBJECTIVES This study questioned whether transaxillary transcatheter aortic valve implantation (TAVI) is feasible as a true percutaneous approach using percutaneous closure devices. BACKGROUND Transaxillary TAVI is gaining increasing acceptance as an alternative to the transfemoral route; however, the access has always been done via surgical cutdown so far. METHODS Between August 2010 and September 2011, a total of 24 high-risk patients with severe aortic valvular stenosis underwent a percutaneous TAVI procedure by direct puncture of the axillary artery without surgical cutdown. For safety reasons and as a target for the puncture, a wire was advanced via the ipsilateral brachial artery. Moreover, a balloon was placed into the subclavian artery via the femoral artery for temporary vessel blockade before percutaneous vessel closure. Vascular closure was performed using either the ProStar XL system (Abbott Vascular Devices, Redwood City, California) or 2 ProGlide systems (Abbott Vascular Devices). RESULTS The true percutaneous approach was successfully completed in all patients (14 left and 8 right axillary artery cases). Overall mortality at 30 days was 8.3%. Acute vascular closure device success was achieved in 17 patients (71%). Vascular closure device success rate was 100% for the ProGlide device and 37% for the ProStar device, respectively. Seven patients (29%) with failing closure devices were treated by endovascular stent graft implantation without the need for surgical repair. For the last 12 treated patients, direct closure was achieved in 11 patients. CONCLUSIONS Direct puncture of the axillary artery for TAVI is feasible and safe if a wire is placed into the subclavian artery via the ipsilateral brachial artery.

Balloon-expandable valves for degenerated mitral xenografts or failing surgical rings.

AIMS Transcatheter mitral valve-in-valve implantation (TMViVI) for the treatment of failing mitral xenografts or recurrent mitral regurgitation after surgical ring implantation is an emerging therapy for patients in need of repeated mitral valve surgery. Despite the fact that these procedures have been shown to be feasible and effective, haemodynamic data after TMViVI are still limited in the literature. METHODS AND RESULTS Twelve patients (logES: 39.2±23.5%) were treated either by transapical (n=7) or transseptal (n=5) TMViVI, as a valve-in-valve (ViV, n=8) or valve-in-ring (ViR, n=4) implantation. Left atrial pressures (LAP), transmitral gradients and right heart haemodynamics (Swan-Ganz catheterisation) were studied before and after TMViVI. Procedural success was 100%, mitral regurgitation after TMViVI was mild in one, trace in five and absent in six patients. Thirty-day mortality was 0%. Left atrial pressures decreased significantly after valve implantation (before LAPmean/v-wave: 24.3/44.1 mmHg; after LAP/v-wave 15.9/22.1 mmHg; p<0.001) and cardiac output increased significantly. Transmitral gradients corresponded to mitral surface areas between 1.7 and 3.5 cm2, and were thus very acceptable in terms of the high surgical risk population. CONCLUSIONS In conclusion, TMViVI with the balloon-expandable SAPIEN XT valve for ViV or ViR implantation is feasible with promising acute transmitral haemodynamic data. Nevertheless, sustained long-term performance remains to be demonstrated in the future.

Emergency transcatheter aortic valve replacement in patients with cardiogenic shock due to acutely decompensated aortic stenosis.

AIMS To assess outcomes of TAVR as a rescue therapy in patients with cardiogenic shock due to acutely decompensated aortic stenosis. METHODS AND RESULTS Of 771 high-risk patients who underwent TAVR, 27 (3.5%; 78±9 years; 12 men) were treated emergently due to acutely decompensated aortic stenosis with cardiogenic shock. SAPIEN and CoreValve prostheses were implanted in 11 and 16 patients, respectively: the transfemoral access route was used in 25. Three patients died within 72 hours of successful valve deployment, and a further six died within a month, giving a 30-day mortality of 33.3%, which was significantly higher than in electively treated patients (7.7%, p<0.0001). Univariate predictors of 30-day mortality in cardiogenic-shock patients were baseline cardiac output <3.0 l/min, reduced cardiac power index, impaired renal function, and mechanical ventilation, as well as severe acute kidney injury after TAVR. Estimated one-year survival was 59.3% in emergently and 82.7% in electively treated patients (p=0.0009). However, 30-day landmark analysis showed no difference in cumulative survival between TAVR modalities. In cardiogenic-shock patients without concomitant reduced cardiac output and impaired renal function at baseline (n=22), estimated one-year survival was 72.7%. CONCLUSIONS TAVR should be considered a reasonable rescue therapy in patients with cardiogenic shock secondary to decompensated aortic stenosis.

Clinical impact of paravalvular leaks on biomarkers and survival after transcatheter aortic valve implantation

There is accumulating evidence that up to 20% of the implanted devices after TAVI are associated with a significant degree of paravalvular leaks, which appear to be associated with a negative clinical outcome.

Transfemoral and Transseptal Valve-in-Valve Implantation Into a Failing Mitral Xenograft With a Balloon-Expandable Biological Valve

Valve-in-valve implantation for degenerated surgical bioprosthetic valves is becoming an increasingly accepted approach in selected high-risk patients. In the past, valve-in-valve implantations have been mainly performed in aortic position and only rarely in mitral position. We describe the case of an 81-year-old female patient with severe mitral regurgitation of a degenerated Carpentier-Edwards biological prosthesis treated by transfemoral and transseptal implantation of a SAPIEN-XT valve.

Targeting systolic anterior motion and left ventricular outflow tract obstruction in hypertrophic obstructed cardiomyopathy with a MitraClip

AIMS Hypertrophic obstructive cardiomyopathy (HOCM) with left ventricular outflow tract obstruction frequently involves a systolic anterior motion (SAM) of the anterior mitral leaflet. We hypothesised that SAM could be a new target for MitraClip therapy. METHODS AND RESULTS Three patients with HOCM were chosen for MitraClip therapy, due to significant SAM with subsequent mitral regurgitation. Invasive haemodynamic studies (right heart catheterisation, simultaneous transaortic pressure recording, and administration of nitroglycerine) were performed before and after MitraClip implantation, and a six-week follow-up was undertaken. MitraClip implantation was successfully performed with significant reduction of mitral regurgitation and SAM in all patients. Basal peak gradients (before clip: 65±25.5 mmHg; after clip: 7.7±5.0 mmHg) as well as provoked pressure gradients (before clip: 145.3±8.1 mmHg; after clip: 23.2±7.6 mmHg) were significantly reduced after MitraClip implantation. Right heart catheterisation data did not reveal major changes. At six-week follow-up, all patients presented in a persistently improved clinical state (NYHA Class I-II) with insignificant residual MR and continuously reduced LVOT gradients. CONCLUSIONS This is the first catheter-based study targeting primarily a SAM in HOCM to reduce LVOT obstruction. The results prove the concept that SAM is more than an epiphenomenon in HOCM. Thus, SAM-induced obstruction might be a valuable target for the MitraClip.

Erratum to: Impact of transcatheter aortic valve implantation (TAVI) on pulmonary hyper-tension and clinical outcome in patients with severe aortic valvular stenosis.

Background Transcatheter aortic valve implantation (TAVI) is a proven alternative to open heart surgery in elderly patients. Pulmonary hypertension (PH) is known as a significant risk factor in patients with severe aortic stenosis (AS) undergoing surgical aortic valve replacement. However, the prognostic impact of PH in high-risk patients undergoing TAVI is still unknown. The aim of this study was to gain more insight in the clinical outcome and mortality of patients with PH after TAVI.

Histological Findings and Predictors of Cerebral Debris From Transcatheter Aortic Valve Replacement: The ALSTER Experience

Background Histopathological analyses of debris captured by a cerebral protection system during transcatheter aortic valve replacement have been reported, but the origin of the captured debris was not determined and risk factors were not defined. Methods and Results Embolic debris was analyzed from 322 filters used in a dual‐cerebral‐filter protection system implemented during transcatheter aortic valve replacement for 161 patients (mean age 81 years, 82 male [51%], logistic EuroSCORE 19% [interquartile range 12–31%]). The debris capture rate was high, with debris from 97% of all patients (156 of 161). No differences by filter location were found (brachiocephalic trunk 86% [139 of 161], left carotid artery 91% [147 of 161]; adjusted P=0.999). Five prevalent types of debris were identified: thrombus (91%), arterial wall tissue (68%), valve tissue (53%), calcification (46%), and foreign material (30%). Female sex (P=0.0287, odds ratio 1.364, 95% CI 1.032–1.812) and diabetes mellitus (P=0.0116, odds ratio 1.474, 95% CI 1.089–2.001) were significant risk factors for embolic debris. Additional analysis showed significantly more valve tissue in patients with predilation (P=0.0294). Stroke and transient ischemic attack rates were 0.6% each (1 of 161). Conclusion This study showed a high rate of embolic debris consisting of typical anatomic structures known to be altered in patients with aortic stenosis undergoing transcatheter aortic valve replacement. Female patients with diabetes mellitus have increased risk of embolic debris and should be protected by a cerebral protection system during transcatheter aortic valve replacement. Because valve tissue embolizes more often in patients with predilation, procedural planning should consider this finding. Both cerebral arteries (brachiocephalic trunk, left carotid artery) should be protected in the same way.

Impact of kidney function on mortality after transcatheter valve implantation in patients with severe aortic valvular stenosis

AIMS Transcatheter aortic valve implantation (TAVI) is an accepted alternative for patients with severe aortic valve stenosis who cannot undergo surgery. Acute kidney injury (AKI) is a serious complication in any invasive cardiovascular intervention. The objectives of the study were to determine (i) the influence of kidney function before TAVI and (ii) the impact of changes in kidney function after TAVI, including acute kidney injury (AKI), on mortality. METHODS AND RESULTS A total of 540 patients undergoing TAVI were included. Patients were divided into three groups according to glomerular filtration rate (GFR) before TAVI (A: normal renal function i.e. GFR ≥60ml/min; B: impaired renal function i.e. GFR 30-59ml/min; C: severe impaired renal function i.e. GFR <30ml/min). Multivariate analysis showed a significant impact of GFR on mortality (p<0.0008). Subgroup analysis showed significant differences between the groups in 30-day (A: 5.4%, B: 9.0%, C: 25.0%) and 12-month mortality (A: 15.0%, B: 32.0%, C: 49%). Patients who had an increase in GFR after TAVI by more than 22% (p=0.0068) had an improved survival rate, whereas a decrease in GFR by more than 15% was associated with an increased mortality rate (p=0.0051). AKI occurred in 30 patients (5.6%), of which 22 patients (73.3%) died within 12months. CONCLUSION Outcome is significantly related to pre-procedural kidney function. In addition, changes in kidney function after TAVI have a significant impact on mortality. Due to a very poor prognosis in patients with AKI, any effort to prevent this serious complication after TAVI needs to be taken.

Transcatheter implantation of aortic valve prostheses into degenerated mitral valve bioprostheses and failed annuloplasty rings: outcomes according to access route and Mitral Valve Academic Research Consortium (MVARC) criteria.

AIMS The study sought to assess outcomes of transcatheter mitral valve-in-valve implantation (TMVIV) for degenerated bioprostheses and transcatheter mitral valve-in-ring implantation (TMVIR) for failed annuloplasty rings according to access route and the Mitral Valve Academic Research Consortium (MVARC) criteria. METHODS AND RESULTS Twenty-four patients (72±13 years; eight men [33%]) underwent TMVIV (n=14) or TMVIR (n=10) for mitral regurgitation (MR; n=17) or stenosis (n=7) using balloon-expandable bioprostheses. Transapical (TA) access was chosen in 13, and transseptal (TS) access in 11 patients. MVARC technical success, device success and procedural success were 95.8%, 41.7% and 33.3%, respectively, with no differences between access routes. Cardiac output (CO) increased significantly by 1.1±0.8 l/min in TS patients, but not in TA patients (ΔCO=0.0±0.5 l/min; p=0.0051). Overall three-year survival was estimated at 57.6% (95% confidence interval: 33.9-81.3; TA 35.5% [5.2-65.9]; TS 90.9% [73.9-100]). Survival up to four years according to vascular access showed a clear benefit in patients treated transseptally (p=0.045). CONCLUSIONS Regardless of the access route, TMVIV/TMVIR was associated with high technical success yet impaired device success. In the long term, TA access had a significant adverse impact on survival.