CoreValve Prosthesis Research Articles

Compassionate use of the self‐expandable medtronic corevalve prosthesis for the treatment of pure aortic regurgitation in a patient at prohibitive risk for surgical valve replacement

Transcatheter aortic valve implantation (TAVI) is a viable treatment option for high- and prohibitive-risk patients with severe, calcified pure or predominant aortic valve stenosis, but not for pure aortic valve regurgitation. In fact, the use of TAVI for this indication is even considered unlikely due to the lack of calcium which appears essential for anchoring the stent-valve and prevents dislocation. We report a case of a patient with severe, symptomatic pure aortic regurgitation, and a history of two previous open-heart surgeries who was successfully treated by compassionate use implantation of an oversized Medtronic CoreValve prosthesis as an ultima ratio treatment option.

Dysfunction of a 21-mm aortic bioprosthesis treated with percutaneous implantation of a CoreValve prosthesis

Percutaneous aortic valve replacement is an emerging alternative for high surgical risk patients with native aortic valve stenosis. We describe for the first time a valve-in-valve procedure with a CoreValve prosthesis for the treatment of a severely stenotic degenerated aortic bioprosthesis.

Percutaneous coronary intervention in TAVI: The “proboscis” catheter

We report a case of an 81-years-old male, recently implanted with a Core Valve (CV) prosthesis and admitted to the ER for acute coronary syndrome. Coronary angiography revealed the patency of the coronary artery by-pass grafts but was impossible to cannulate the left main "imprisoned" by the CV prosthesis struts. Aortography showed an excessive gap between the CV struts and the coronary ostium. To cross the CV struts, we developed a "proboscis" catheter by cutting away the proximal end of the 7F JL 4 catheter and putting inside the 5F Heartrail catheter. The following angiograms showed a critical stenosis in the proximal obtuse marginal (branch), successfully treated with a bare-metal stent implantation.

Transcatheter implantation of self-expanding valve for failed stentless aortic root bioprosthesis

Although repeat aortic valve replacement (AVR) remains the standard treatment for failed bioprostheses, the feasibility of transcatheter aortic valve implantation (TAVI) has also been demonstrated. We report the successful implantation of a CoreValveTM self expanding aortic prosthesis (Medtronic, Inc) in a patient with a degenerated BioConduitTM stentless valve conduit (Shelhigh, Inc). A 63 year-old man was admitted due to NYHA class IV heart failure symptoms. He had a history of triple percutaneous coronary intervention followed by AVR plus LIMA to LAD grafting. Two years after the first surgery, acute dissection of the ascending aorta occurred and the mechanical valve along with the proximal ascending aorta were replaced by a stentless 25 mm valve conduit. Postoperative mediastinitis and atrio-ventricular block warranted sternum refixation and pacemaker implantation. Another year later, the patient underwent conservative treatment for prosthetic valve endocarditis. On current admission, transthoracic and transoesophageal echocardiography (TTE, TEE) revealed left ventricle (LV) end-diastolic diameter (EDD) of 62 mm and ejection fraction (EF) of 25%. Bioprosthetic cusps were opening well but seemed perforated and had attached two additional structures of ultrasound intensity, irregular shape and high mobility corresponding to organised bacterial vegetations. Consequently, severe aortic regurgitation (AR) was present. On coronary angiography, the arterial graft was occluded and no revascularisation within native coronaries was required. The unfavourable anatomical environment expected after mediastinitis accompanied by high STS scoring (16%) and wide peripheral arteries contributed to a decision to reject reoperation in favour of the transcatheter approach. On multi-detector computed tomography (MDCT), the prosthesis length was 45 mm with significant angulation of neighbouring ascending aorta and coronaries reimplanted 12 mm and 17 mm above the valve (Fig. 1). Laboratory findings excluded active infective endocarditis. After induction of general anaesthesia, a Prostar XL (Abbott) device was introduced into the right common femoral artery. Next, a 26 mm CoreValve prosthesis (the size had been selected according to the inner BioConduit diameter of 22 mm by TEE, standard delivery system) was positioned and deployed in a retrograde manner. Lack of fluoroscopy markers such as calcifications or rigid ring rendered the procedure more TEE-dependent. After completion, no transprosthetic gradient was measured and residual paravalvular AR was trivial. Nevertheless, deficient expansion of the stent frame distal part within the non-pliable BioConduit was noted. The time from arterial puncture to closure was 65 min with 22 min of fluoroscopy, and 180 mL of contrast agent was used. The post-procedural course was uneventful and the patient remained asymptomatic at 12-month follow-up. A remarkable improvement in LV performance was noted, with EDD of 54 mm and EF of 56% by TTE. Repeated MDCT visualised uncompromised coronaries ostia and persistent distal stent frame deformation. Proximal circularity remained however unaffected, which corresponded to the valve’s excellent function (Figs. 2, 3). Initial balloon valvuloplasty may optimise transcatheter valve stent alignment at the expense of degenerated bioprosthesis fragmentation and peripheral embolisation. The anticipated fragility of the thin-walled bioprosthetic cuff further added to our refraining from the manoeuvre. Lack of natural aorta sinus widening in patients with full root prostheses renders coronary flow impairment during TAVI more likely. This was avoided by careful positioning of the CoreValve sealing skirt below the coronaries’ ostia.

Survival, Predictive Factors, and Causes of Mortality following Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is considered the standard of care for patients with severe symptomatic aortic stenosis unsuitable for surgery. However, short- and long-term mortality after TAVI are still relatively high. The aim of this study was to establish survival, predictive factors, and causes of mortality after TAVI at early and midterm follow-up. Between December 2007 and May 2012, a total of 119 patients with symptomatic severe aortic stenosis underwent 121 TAVI procedures. The mean ± SD age was 81 ± 9 years, and 59% were men. The mean ± SD logistic European System for Cardiac Operative Risk Evaluation was 22 ± 15. Seventy-five patients (63%) were in New York Heart Association functional class III to IV. The transfemoral approach was used in 76% of the patients. One hundred ten patients (91%) had the CoreValve prosthesis, and 11 (9%) had an Edwards SAPIEN valve. Baseline characteristics, procedural complications, and outcomes were collected prospectively. Clinical outcomes were defined according to the Valve Academic Research Consortium criteria. Follow-up was completed for 100% of the patients at a median of 1.3 years (range, 0-4.5). The total number of deaths was 36 (30%). One-month mortality was 4.2%. Actuarial survival was 83.2%, 76.5%, and 68.2% at 1, 2, and 3 years, respectively. Acute kidney injury occurred in 12.3% of the patients, none of whom required dialysis during hospitalization. Twenty-one patients (17.6%) had new conduction abnormalities that required permanent pacemaker implantation before hospital discharge. The incidence of major vascular injury and stroke was 2.4% and 4.1%, respectively. Survival was significantly adversely affected by preprocedural left ventricular dysfunction (P = 0.04), history of atrial fibrillation (P = 0.03), prior heart block (P < 0.01), and critical preoperative state (P < 0.01). Twelve (33%) of the 36 deaths were due to bronchopneumonia. In 12 (33%) of the 36 patients who died, mortality was related to cardiac causes. When a death occurred within the first 30 days, it was mainly cardiac in nature (80%). Twelve patients (34%) died because of a variety of other reasons such as pulmonary embolism, stroke, cancer, renal failure, and sepsis. Preprocedural left ventricular dysfunction, atrial fibrillation, and heart block are independent predictive factors of all-cause mortality. Early mortality was mainly cardiac in origin. Most of the late deaths were caused by noncardiac reasons, with bronchopneumonia being reported as the most common cause of late mortality.

Case reports of bail-out maneuvers for implantation of a second core valve prosthesis during the same TAVI procedure

Case reports of bail-out maneuvers for implantation of a second core valve prosthesis during the same TAVI procedure

Safety and efficacy of the subclavian access route for TAVI in cases of missing transfemoral access

We retrospectively analysed our experience with the subclavian access transcatheter aortic valve implantation (TAVI) with the self-expandable CoreValve prosthesis and compared the results with transfemorally treated patients. For TAVI, a subclavian access is alternatively used when the femoral arteries are diseased or very small. Between June 2007 and February 2011, 341 patients underwent CoreValve implantation in the German Heart Center, Munich through either transfemoral (n = 301) or subclavian (n = 40) approach. The subclavian approach was chosen where transfemoral approach was not possible. There was no difference in baseline characteristics between the groups. There were no significant differences between groups for parameters potentially related to improved valve positioning (contrast medium, fluoroscopy time, implantation of a second valve, post-implantation balloon dilatation, valve dislocation, pacemaker implantation, aortic regurgitation), while the procedure duration was longer (105 ± 40 vs. 82 ± 33 min, p = 0.001). With the Kaplan-Meier estimate, survival was not different among groups. Strokes, myocardial ischaemia, and access vessel complications occurred in 2.5, 0, and 7.5 % (subclavian group) vs. 4.3, 2.0, 10.6 % (transfemoral group), ns. Our results demonstrate the safety of the subclavian access for TAVI and comparability with the transfemoral approach. With longer duration of the procedure and no significant advantages in clinical outcome, the subclavian access will have an indication for selected patients, while transfemoral TAVI should be considered first choice.

Radiation dose of patients undergoing transcatheter aortic valve implantation: A comparison between edwards SAPIEN XT and medtronic corevalve aortic valve prostheses

The relative radiation dose (RD) of patients undergoing transcatheter aortic valve implantation (TAVI) with either the Edwards Sapien XT (ESX) or the Medtronic CoreValve (MCV) prostheses has not been studied in depth. Our aim was to quantify RD in uncomplicated transfemoral TAVI with either prosthesis. We analyzed 248 consecutive patients undergoing uncomplicated transfemoral TAVI between March 2009 and September 2012, at a single tertiary care facility. Total air Kerma, cumulated dose area product (DAP), and fluoroscopy time were determined in each case. The ESX and MCV prostheses were implanted in 44 and 204 patients, respectively. Though mean fluoroscopy time was higher during ESX valve implantation, overall RD per total air Kerma and DAP was significantly higher during MCV implantation (P < 0.05 for both comparisons). By multivariate regression analyses, prosthesis type was an independent predictor of RD according to both total air Kerma and DAP (r(2) = 0. 498; P < 0.01 and r(2) = 0.363; P < 0.01, respectively). In uncomplicated transfemoral TAVI, RD is greater during MCV implantation than during ESX implantation.

Mid-term prognostic value of coronary artery disease in patients undergoing transcatheter aortic valve implantation: A meta-analysis of adjusted observational results

Coronary artery disease (CAD) negatively affects prognosis in patients undergoing surgical aortic valve replacement, being currently evaluated in the most common used risk score. Our meta-analysis aims to clarify the prognostic role of CAD on mid-term survival in patients undergoing TAVI. Studies reporting multivariate predictors of adverse outcomes in patients undergoing TAVI were systematically searched for and pooled, when appropriate, using a random-effect method. 960 citations were first screened and finally 7 studies (2472 patients) were included. Diagnosis of CAD was reported in 52%(42-65) of patients and 1169 Edwards SAPIEN and 1303 CoreValve prostheses were implanted. After a median follow up of 452 days (357-585) 24% of patients (19-33) died, and 23 (14-32) for cardiovascular death. At pooled analysis of multivariate approach, diagnosis of coronary artery disease did not increase risk of death (OR 1.0, 95% CI, confidence interval, 0.67-1.50 I(2) 0%). CAD does not affect mid-term TAVI outcome: this finding should be weighted to accurately evaluate risk and strategies for patients with severe aortic stenosis.

Transcatheter aortic valve implantation without balloon predilation: A single‐center pilot experience

To assess the results of transcatheter aortic valve implantation (TAVI) using the Medtronic CoreValve prosthesis (Medtronic, Minneapolis, MN), without balloon predilation, in high-risk patients with degenerated severe aortic stenosis. Fifty-one consecutive patients who underwent direct TAVI, 98% through a transfemoral approach. Patients were 79 ± 8 years of age, 74% in New York Heart Association classes III or IV and at high risk for surgical valve replacement (mean logistic EuroScore 20 ± 15). Mean aortic valve area was 0.7 ± 0.2 cm(2). Procedural success rate was 94.2%. In-hospital, there were 2 deaths, 1 minor stroke with minimal sequelae, and 14 (28%) pacemaker implantation. At 30 days, there was one additional stroke and no new deaths. The mean postprocedural transprosthetic gradient was 15 ± 5 mm Hg; periprosthetic severe regurgitation was absent and moderate in one case. After a median follow-up of 7 months, there were five additional deaths (two cardiac), while 84% of survivors were in New York Heart Association classes I or II. These results suggest that direct CoreValve implantation in patients with severe aortic stenosis is feasible and may lead to hemodynamic and clinical improvement in patients who are poor candidates for aortic valve surgery, pending confirmation in larger series with longer follow-up.

Multiple cerebral emboli following dislocation and retraction of a partially deployed CoreValve prosthesis during transcatheter aortic valve implantation

Transcatheter aortic valve implantation for patients with severe aortic stenosis at a high-operative risk has been demonstrated to improve mortality compared to standard medical therapy. Registry data and the PARTNER trial have shown a significant risk of stroke (3-5%) following the procedure. Studies using cerebral diffusion-weighted magnetic resonance imaging have suggested the mechanism of stroke to be multiple small embolic infarcts, possibly from aortic atheroma dislodged during the movement of the valve and its apparatus around the thoracic aorta. The incidence of these infarcts is higher than clinically apparent. The Medtronic CoreValve (Medtronic, Minneapolis, Minnesota) prosthesis is a self-expanding nitinol frame with porcine valve, whose deployment is achieved by the retraction of the delivery catheter. Potential complications of this method include valve mal-positioning and dislocation. The partially deployed valve may then be resheathed following retraction back into the descending aorta and subsequently redeployed. We present two such cases with evidence of both "silent" and clinically evident cerebral infarction.

Transcatheter aortic valve‐in‐valve implantation of a corevalve in a degenerated stenotic sapien heart valve prosthesis

Treatment options for re-stenotic aortic valve prosthesis implanted by transcatheter technique have not been evaluated systematically. We describe the case of a 75-year-old dialysis patient who was treated by transcatheter aortic valve implantation 3.5 years ago and now presented with severe stenosis of the percutaneous heart valve. The patient was initially treated with a trans-apical implantation of an Edwards Sapien 26 mm balloon expandable valve. The patient remained asymptomatic for 3 years when he presented with increasing shortness of breath and significant calcification of the valve prosthesis on transesophageal echocardiography. Valve-in-valve percutaneous heart valve implantation using a 26-mm CoreValve prosthesis was performed under local anesthesia. The prosthesis was implanted without prior valvuloplasty. Pacing with a frequency of 140/min was applied during placement of the valve prosthesis. Positioning was done with great care using only fluoroscopic guidance with the aim to have the ventricular strut end of the CoreValve prosthesis 5 mm higher than the ventricular strut end of the Edwards Sapien prosthesis. After placement of the CoreValve prosthesis within the Edwards Sapien valve additional valvuloplasty with rapid pacing was performed in order to further expand the CoreValve prosthesis. The final result was associated with a remaining mean gradient of 5 mm Hg and no aortic regurgitation. In conclusion, implantation of a CoreValve prosthesis for treatment of a restenotic Edwards Sapien prosthesis is feasible and is associated with a good functional result.

Conduction disorders in the setting of transcatheter aortic valve implantation: a clinical perspective

The presence of periprocedural conduction disorders (CDs) and the need for permanent pacemaker (PPM) after transcatheter aortic valve implantation (TAVI) are frequent findings in clinical practice. Notwithstanding, robust information on the prognostic and therapeutic implications of these complications are lacking. The newly occurrence of CD after TAVI seems related to the trauma of the conduction system during procedure. On the contrary, major predictors for PPM implantation after TAVI seem to be the use of CoreValve prosthesis (Medtronic, Minneapolis, MN) and the presence of CD before TAVI. An accurate pre-TAVI screening, careful valve implantation, as well as post-TAVI monitoring must be pursued to prevent avoidable PPM implantation. The aim of this report is to analyze the available data on this field and to propose some practical clinical tips to prevent or to manage these complications.

Left atrial diameter, aortic mean gradient, and hemoglobin for risk stratification in patients undergoing transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) is an alternative treatment of severe symptomatic aortic stenosis (AS) in patients with high operative risk. In spite of favorable entire results, long-term mortality of patients is high. The present study aims to identify independent preprocedural risk factors to improve risk stratification in these highly selected patients. This prospective study included 202 consecutive patients with severe symptomatic AS and high operative risk (mean logistic European System for Cardiac Operative Risk Evaluation, 22±17%; mean age, 79±6 years; 107 female). Preprocedural comprehensive examinations were performed (laboratory, electrocardiography, echocardiography, cardiac catheterization). All patients received transfemoral or transaxillary TAVI with a CoreValve prosthesis (Medtronic, Minneapolis, MN). During a follow-up of 535±333 days, 56 patients (28%) reached the primary study end point (all-cause mortality). Independent predictors of long-term mortality were as follows: hemoglobin<12.5 g/dL (hazard risk [HR], 3.62; 95% confidence interval [CI], 2.025-6.468; P<0.001), aortic mean gradient≤41 mm Hg (HR, 2.16; 95% CI, 1.272-3.655; P=0.004), and left atrial diameter>42 mm (HR, 3.09; 95% CI, 1.588-6.019; P=0.001). Our risk-stratification model based on these independent predictors separated patients into 4 groups with high (74%), intermediate (37%), low (18%), and very low (3%) all-cause mortality. In patients undergoing TAVI, preprocedural assessment of hemoglobin, aortic mean gradient, and left atrial diameter provides independent prognostic information and therefore contributes to improved risk stratification in TAVI.

Successful Transapical Implantation of an Edwards Sapien Valve Within an Insufficient Aortic CoreValve Prosthesis: An Initial Experience

Transcatheter aortic valve implantation (TAVI) has become an emerging alternative for high-risk patients with aortic stenosis unsuitable for surgical intervention. We report the case of a 26-mm Edwards Sapien valve (Edwards Lifesciences, Irvine, CA) implanted into an insufficient 29-mm CoreValve prosthesis (Medtronic Inc, Minneapolis, MN) 1 year after implantation using the transapical approach in a 59-year-old man. Transesophageal echocardiography showed severe paravalvular regurgitation and computed tomography revealed the CoreValve to be located slightly below the aortic annulus with evidence of underdeployment. The balloon-expandable Sapien system caused a better expansion of the underdeployed CoreValve and the pericardial skirt adequately covered the leakage. The paravalvular regurgitation disappeared and the patient recovered.

How should I treat a patient with symptomatic severe aortic stenosis and a 23 mm aortic annulus who is referred for transcatheter aortic valve replacement using the CoreValve prosthesis?

How should I treat a patient with symptomatic severe aortic stenosis and a 23 mm aortic annulus who is referred for transcatheter aortic valve replacement using the CoreValve prosthesis?

Comparison of Hemodynamic Performance of Self-Expandable CoreValve Versus Balloon-Expandable Edwards SAPIEN Aortic Valves Inserted by Catheter for Aortic Stenosis

Transcatheter aortic valve implantation with the self-expandable CoreValve (CV) and the balloon-expandable Edwards SAPIEN (ES) bioprostheses has been widely used for the treatment of severe aortic stenosis. However, a direct comparison of the hemodynamic results associated with these 2 prostheses is lacking. The aim of the present study was to compare the hemodynamic performance of both bioprostheses. A total of 41 patients who underwent transcatheter aortic valve implantation with the CV prosthesis were matched 1:1 for prosthesis size (26 mm), aortic annulus size, left ventricular ejection fraction, body surface area, and body mass index with patients who underwent transcatheter aortic valve implantation with the ES prosthesis. Doppler-echocardiographic data were prospectively collected before the intervention and at hospital discharge, and all examinations were sent to, and analyzed in, a central echocardiography core laboratory. The mean transprosthetic residual gradient was lower (p = 0.024) in the CV group (7.9 ± 3.1 mm Hg) than in the ES group (9.7 ± 3.8 mm Hg). The effective orifice area tended to be greater in the CV group (1.58 ± 0.31 cm(2) vs 1.49 ± 0.24 cm(2), p = 0.10). The incidence of severe prosthesis-patient mismatch was, however, similar between the 2 groups (effective orifice area indexed to the body surface area ≤0.65 cm(2)/m(2); CV 9.8%, ES 9.8%, p = 1.0). The incidence of paravalvular aortic regurgitation was greater with the CV (grade 1 or more in 85.4%, grade 2 or more in 39%) than with the ES (grade 1 or more in 58.5%, grade 2 or more in 22%; p = 0.001). The number and extent of paravalvular leaks were greater in the CV group (p <0.01 for both comparisons). In conclusion, transcatheter aortic valve implantation with the CV prosthesis was associated with a lower residual gradient but a greater rate of paravalvular aortic regurgitation compared to the ES prosthesis. The potential clinical consequences of the differences in hemodynamic performance between these transcatheter heart valves needs to be addressed in future studies.

108: Impact of the method used for aortic annulus measurement on TAVI results - A transesophageal echocardiography and multislice computed tomography comparison

Accurate measurement of the aortic annulus diameter (AD) is critical for successful implantation of transcatheter aortic valve (TAVI) but the best method is still debated. We sought to compare the results of TAVI according to the method finally used for the choice of the prosthesis size: transesophageal echocardiography (TEE) or multislice computed tomography (MSCT). AD was measured using both TEE and MSCT in 177 patients who underwent TAVI using either the Edwards Sapien or the Medtronic Corevalve prosthesis between January 2008 and April 2011. AD was measured from the long-axis view using TEE and at the level of the virtual basal ring in MSCT (mean of long and short axis). Agreement was defined as the use of the same prosthesis size with both TEE and MSCT according to manufacturers’ recommendations. Overall, mean AD was significantly larger using MSCT than TEE (24.6±2.2 vs. 23.2±1.93 mm, p<.0001). An agreement between TEE and MSCT was observed in 118 patients. Among the 59 patients with TEE and MSCT disagreement, prosthesis size was chosen according to TEE measurements in 54 and according to MSCT in 5. The Table summarized complications and in-hospital mortality. There was no significant difference between groups except for annulus rupture which occurred in one patient in whom MSCT measurements were used. The present study shows that a TEE-based choice of the prosthesis size provided excellent clinical results not significantly different than when both MSCT and TEE agreed. Thus, in patients undergoing TAVI, the best imaging modality for the measurement of the aortic annulus diameter remains still not established but our data do not support the use of CT as the first line method. Table – Complications and in-hospital mortality. Complications TEE/MSCT agreement N= 118 TEE-based strategy N=54 MSCT-based strategy N=5 P value Aortic regurgitation ≥2/4, n (%) 3 (3%) 3 (6%) 0 0.57 Second baloon inflation, n (%) 3 (3%) 3 (6%) 0 0.57 Second prosthesis implantation, n (%) 2 (2%) 2 (4%) 0 0.71 Annulus rupture, n (%) 1 (1%) 1 (2%) 1 (20%) 0.009 Prosthetic migration, n (%) 1 (1%) 0 0 0.77 In hospital mortality, n (%) 10 (8%) 1 (2%) 1 (20%) 0.68

Transesophageal echocardiography measurements of aortic annulus diameter using biplane mode in patients undergoing transcatheter aortic valve implantation

BackgroundAortic stenosis (AS) is a relevant common valve disorder. Severe AS and symptoms and/or left ventricular dysfunction (EF <50%) have the indication for aortic valve replacement (AVR). Majority of the patients with AS are elderly often with co-morbidities and generally have high preoperative risk. Transcatheter aortic valve implantation (TAVI) is offered in this group. Four different sizes of Corevalve prosthesis are available. Correct measurement of aortic size prior to TAVI is of great important to choose the right prosthesis size to avoid among others paravalvular leak or prosthesis patient mismatch.Aim of the study is to assess the aortic annulus diameter in patients undergoing TAVI by biplane (BP) mode using transesophageal echocardiography (TEE) and compare it to two-dimensional (2D) transthoracic echocardiography (TTE) and 2DTEE using three-dimensional (3D) TEE as reference method.MethodsThe study population consisted of 50 patients retrospectively (24 men and 26 women, mean age 85±8 years of age) who all had undergone echocardiography examination prior to TAVI.ResultsThe mean aortic annulus diameter was 20.4±2.2 mm with TTE, 22.3±2.5 mm with 2DTEE, 22.9±1.9 mm with BP-mode and 23.1±1.9 mm with 3DTEE. TTE underestimated the mean aortic annulus diameter in comparison to transesophageal imaging modalities (p<0.001). Using 3DTEE, 2% of patients were unsuitable for TAVI due to a too-small AoA (n=1). This figure was similar with BP (4%, n=2; p=1.00) but considerably larger with 2DTTE (36%, n=18; p < 0.001) and 2DTEE (12%, n=6; p=0.06). There was a strong correlation between BP-mode and 3DTEE for assessment of aortic annulus diameter (r-value 0.88) with small mean difference (−0.2±0.9 mm) whereas the other modalities showed larger 95% confidence interval and modest correlation (2DTTE vs. 3DTEE, –6.3 to 0.9 mm, r=0.64 and 2DTEE vs. 3DTEE, –4.8 to 3.2 mm, r=0.61).ConclusionA multi-dimensional method is preferred to assess aortic annulus diameter in TAVI patients since there is risk of underestimation using single plane. Biplane mode is the method of choice in view of speedy post-processing with no need for expensive dedicated software. Lastly, single plane methods lead to misclassification of patients as unsuitable for TAVI. This may be of major clinical importance.

Pharmacodynamic Effect of Clopidogrel in Patients Undergoing Transcatheter Aortic Valve Implantation

The aim of this study was to analyze periprocedural and mid-term effect of clopidogrel on platelet function using the VerifyNow P2Y12 point-of-care assay in patients undergoing TAVI. Platelet reactivity was measured at the beginning of the procedure after 300 mg clopidogrel bolus administration and during the follow-up (at 1 month after the procedure) in 52 patients undergoing TAVI using the Medtronic CoreValve prosthesis (Medtronic CoreValve). A cutoff value of 240 PRU was used to identify nonresponders to clopidogrel treatment with high residual platelet reactivity (HRPR). Baseline HRPR was identified in 80% of patients and in 72% of patients during 6-month follow-up. There was no significant difference in the pharmacodynamic effects of clopidogrel on platelet reactivity from baseline to 6-months follow-up (297 ± 57 vs. 275 ± 62; P = 0.058). Ischemic event occurred only in 3 patients (5.8%) from the study group. In conclusion, majority of patients undergoing TAVI had high residual platelet reactivity after pretreatment with 300 mg of clopidogrel and during the 6-month follow-up at dual antiplatelet treatment. The noneffectiveness of clopidogrel in the TAVI population raises the question of the routine use of dual antiplatelet treatment in this setting.