Amber Otten

Three dimensional evaluation of the aortic annulus using multislice computer tomography: are manufacturer's guidelines for sizing for percutaneous aortic valve replacement helpful?

AIMS To evaluate the effects of applying current sizing guidelines to different multislice computer tomography (MSCT) aortic annulus measurements on Corevalve (CRS) size selection. METHODS AND RESULTS Multislice computer tomography annulus diameters [minimum: D(min); maximum: D(max); mean: D(mean) = (D(min) + D(max))/2; mean from circumference: D(circ); mean from surface area: D(CSA)] were measured in 75 patients referred for percutaneous valve replacement. Fifty patients subsequently received a CRS (26 mm: n = 22; 29 mm: n = 28). D(min) and D(max) differed substantially [mean difference (95% CI) = 6.5 mm (5.7-7.2), P < 0.001]. If D(min) were used for sizing 26% of 75 patients would be ineligible (annulus too small in 23%, too large in 3%), 48% would receive a 26 mm and 12% a 29 mm CRS. If D(max) were used, 39% would be ineligible (all annuli too large), 4% would receive a 26 mm, and 52% a 29 mm CRS. Using D(mean), D(circ), or D(CSA) most patients would receive a 29 mm CRS and 11, 16, and 9% would be ineligible. In 50 patients who received a CRS operator choice corresponded best with sizing based on D(CSA) and D(mean) (76%, 74%), but undersizing occurred in 20 and 22% of which half were ineligible (annulus too large). CONCLUSION Eligibility varied substantially depending on the sizing criterion. In clinical practice both under- and oversizing were common. Industry guidelines should recognize the oval shape of the aortic annulus.

Geometry and Degree of Apposition of the CoreValve ReValving System With Multislice Computed Tomography After Implantation in Patients With Aortic Stenosis

OBJECTIVES Using multislice computed tomography (MSCT), we sought to evaluate the geometry and apposition of the CoreValve ReValving System (CRS, Medtronic, Luxembourgh, Luxembourgh) in patients with aortic stenosis. BACKGROUND There are no data on the durability of percutaneous aortic valve replacement. Geometric factors may affect durability. METHODS Thirty patients had MSCT at a median 1.5 months (interquartile range [IQR] 0 to 7 months) after percutaneous aortic valve replacement. Axial dimensions and apposition of the CRS were evaluated at 4 levels: 1) the ventricular end; 2) the nadir; 3) central coaptation of the CRS leaflets; and 4) commissures. Orthogonal smallest and largest diameters and cross-sectional surface area were measured at each level. RESULTS The CRS (26-mm: n = 14, 29-mm: n = 16) was implanted at 8.5 mm (IQR 5.2 to 11.0 mm) below the noncoronary sinus. None of the CRS frames reached nominal dimensions. The difference between measured and nominal cross-sectional surface area at the ventricular end was 1.6 cm(2) (IQR 0.9 to 2.6 cm(2)) and 0.5 cm(2) (IQR 0.2 to 0.7 cm(2)) at central coaptation. At the level of central coaptation the CRS was undersized relative to the native annulus by 24% (IQR 15% to 29%). The difference between the orthogonal smallest and largest diameters (degree of deformation) at the ventricular end was 4.4 mm (IQR 3.3 to 6.4 mm) and it decreased progressively toward the outflow. Incomplete apposition of the CRS frame was present in 62% of patients at the ventricular end and was ubiquitous at the central coaptation and higher. CONCLUSIONS Dual-source MSCT demonstrated incomplete and nonuniform expansion of the CRS frame, but the functionally important mid-segment was well expanded and almost symmetrical. Undersizing and incomplete apposition were seen in the majority of patients.

Frequency, determinants, and prognostic effects of acute kidney injury and red blood cell transfusion in patients undergoing transcatheter aortic valve implantation

Objectives: To determine the frequency and independent predictors of acute kidney injury (AKI) in addition to the prognostic implications of both AKI and periprocedural red blood cell (RBC) transfusions on 30 day and cumulative late mortality in patients undergoing transcatheter aortic valve implantation (TAVI). Background: RBC transfusions have been reported to predict AKI following TAVI. Data on the prognostic implications of both factors, however, are lacking. Methods: 126 consecutive patients underwent TAVI with the Medtronic CoreValve Revalving System. AKI was defined according to the valve academic research consortium definitions as an absolute increase in serum creatinine ≥0.3 mg dL−1 (≥26.4 μmol L−1) or a percentage increase ≥50% within 72 hr following TAVI. Results: Five patients on chronic haemodialysis and three intraprocedural deaths were excluded, leading to a final study population of 118 patients. AKI occurred in 19% of the patients necessitating temporary haemodialysis in 2%. Independent predictors of AKI included: previous myocardial infarction (OR: 5.72; 95% CI: 1.64–19.94), periprocedural (<24 hr) RBC transfusions (OR: 1.29; 95% CI: 1.01–1.70), postprocedural (<72 hr) leucocyte count (OR: 1.18; 95% CI: 1.02–1.37), and logistic EuroSCORE (OR: 1.08; 95% CI: 1.01–1.14). In patients with AKI, 30‐day mortality was 23% and cumulative late mortality (median: 13 months) was 55%. AKI (OR: 5.47; 95% CI: 1.23–24.21) and postprocedural leucocyte count (OR: 1.20; 95% CI: 1.03–1.38) were independent predictors of 30‐day mortality while AKI (HR: 2.79; 95% CI: 1.36–5.71) was the only independent predictor of late mortality. Conclusions: AKI following TAVI occurred in 19% of the patients. RBC transfusion was found to be an independent predictor of AKI, which in turn predicted both 30‐day and cumulative late mortality.

Changes in mitral regurgitation after transcatheter aortic valve implantation

Objectives: To assess the acute and intermediate changes in mitral regurgitation (MR) severity after transcatheter aortic valve implantation (TAVI) with the CoreValve Revalving SystemTM (CRS). Background: Following surgical aortic valve replacement, improvement in MR is reported in 27–82% of the patients. The changes in MR severity following CRS implantation are unknown. Methods: Transthoracic echocardiography was performed in 79 consecutive patients before and after treatment, and at the first outpatient visit. Left ventricular dimensions and ejection fraction (LVEF), left atrial (LA) size, and aortic gradient were measured. MR was assessed by color flow mapping and was graded as none, mild, moderate, or severe. It was defined as organic or functional. The depth of CRS implantation was measured by angiography. Results: Post‐treatment, the mean gradient decreased from 48 ± 16 mm Hg to 9 ± 5 mm Hg (P < 0.0001). There was no significant change in the left ventricular dimensions, LA size, and LVEF. MR pretreatment was mild, moderate, or severe in 57%, 18%, and 1% of the patients, respectively. It was defined as organic in 27 patients (36%) and functional in 27 patients (36%). The degree of MR remained unchanged in 61% of the patients, improved in 17%, and worsened in 22%. MR improvement was associated with a lower baseline LVEF (P = 0.02). There was no association between the changes in MR severity and the depth of CRS implantation. Conclusions: Most patients who underwent TAVI had some degree of MR. Overall there was no change in the degree of MR post‐treatment. Patients in whom MR improved had a lower LVEF at baseline.

Persistent conduction abnormalities and requirements for pacemaking six months after transcatheter aortic valve implantation

AIMS Early conduction abnormalities and need for pacemaking after transcatheter aortic valve implantation (TAVI) is well recognised. It is still unknown, however, if these conduction abnormalities are persistent, and what is the need for permanent pacemaking after 1-month follow-up. In this prospective study, we examined the incidence of post-procedural and 6-month conduction abnormalities and need for permanent pacemaking after TAVI. METHODS AND RESULTS We examined the 12-lead electrocardiogram (ECG) of 91 consecutive patients in whom a Medtronic CoreValve ReValving System was implanted between November 2005 and April 2009. We evaluated the ECGs before treatment, after treatment, at 1-month and 6-month follow-up. The requirement and timing of permanent pacemaking was documented. The mean age of patients was 81±7 years and the mean logistic EuroSCORE was 16±9%. Median duration of follow-up was 213 days (IQR 64, 519). There was a 39% increase in the frequency of LBBB after TAVI (15% before treatment vs. 54% after treatment, p<0.001). Importantly, there was no significant change in the frequency of LBBB from after treatment to 1- or 6-month follow-up (54% after treatment vs. 42% at 1-month follow-up, p=0.45, and 54% after treatment vs. 45% at 6-month follow-up, p=0.39). Permanent pacemaking was required in 17/91 (19%) of patients. A permanent pacemaker was implanted in 8/17 patients (47%) within seven days of TAVI, in 6/17 (35%) at 7-30 days, and in 3/17 (18%) after 30 days. Male gender, previous myocardial infarction, pre-existing right bundle branch block, actual diameter (mm) of the inflow portion of the CoreValve frame post-implantation and depth of implantation were predictors for new LBBB; pre-treatment QRS duration (msec) and septal wall thickness were predictors for permanent pacemaking. CONCLUSIONS These results suggest that early conduction abnormalities occurring after TAVI persist at 6-months follow-up. Patient-related, anatomical-related, and procedure-related factors need to be considered in the pathogenesis of conduction abnormalities after TAVI.

Early echocardiographic evaluation following percutaneous implantation with the self-expanding CoreValve Revalving System aortic valve bioprosthesis.

AIMS Although safety and feasibility studies have been published, there are few reports dedicated to the echocardiographic evaluation of patients following percutaneous aortic valve replacement (PAVR). This report describes the early echocardiographic evaluation of patients undergoing PAVR with the CoreValve Revalving System. METHODS AND RESULTS The population consisted of 33 consecutive patients with aortic stenosis who underwent successful PAVR. Echocardiograms were performed pre-treatment (123+/-110 days prior), post-treatment (6+/-2 days) and post-discharge (80+/-64 days). Aortic valve function and left ventricular dimensions, systolic and diastolic function were assessed pre- and post-implantation. The mean age was 81+/-7 years and the mean Logistic Euroscore was 20+/-12. Following PAVR, the mean transaortic valve gradient decreased (46+/-16 mmHg pre-treatment vs. 12+/-7 mmHg post-treatment vs. 9+/-5 mmHg post-discharge, p<0.001) and the mean effective orifice area increased (0.75+/-0.23 cm2 pre-treatment vs. 1.97+/-0.85 cm2 post-treatment vs. 1.72+/-0.45 cm2 post-discharge, p<0.001). There was no significant change in mean ejection fraction (41+/-12% pre-treatment vs. 46+/-15% post-treatment vs. 44+/-13% post-discharge, p=0.44). Approximately two-thirds of patients had no change in diastolic function at follow-up. CONCLUSION Following implantation, there was a sustained decrease in aortic valve gradient and increase in aortic valve area. In addition, the mean ejection fraction did not change significantly and in the majority of patients, diastolic function was unchanged.

A comparison of patient characteristics and 30-day mortality outcomes after transcatheter aortic valve implantation and surgical aortic valve replacement for the treatment of aortic stenosis: a two-centre study

AIMS It is unclear whether transcatheter aortic valve implantation (TAVI) addresses an unmet clinical need for those currently rejected for surgical aortic valve replacement (SAVR) and whether there is a subgroup of high-risk patients benefiting more from TAVI compared to SAVR. In this two-centre, prospective cohort study, we compared baseline characteristics and 30-day mortality between TAVI and SAVR in consecutive patients undergoing invasive treatment for aortic stenosis. METHODS AND RESULTS We pre-specified different adjustment methods to examine the effect of TAVI as compared with SAVR on overall 30-day mortality: crude univariable logistic regression analysis, multivariable analysis adjusted for baseline characteristics, analysis adjusted for propensity scores, propensity score matched analysis, and weighted analysis using the inverse probability of treatment (IPT) as weights. A total of 1,122 patients were included in the study: 114 undergoing TAVI and 1,008 patients undergoing SAVR. The crude mortality rate was greater in the TAVI group (9.6% vs. 2.3%) yielding an odds ratio [OR] of 4.57 (95%-CI 2.17-9.65). Compared to patients undergoing SAVR, patients with TAVI were older, more likely to be in NYHA class III and IV, and had a considerably higher logistic EuroSCORE and more comorbid conditions. Adjusted OR depended on the method used to control for confounding and ranged from 0.60 (0.11-3.36) to 7.57 (0.91-63.0). We examined the distribution of propensity scores and found scores to overlap sufficiently only in a narrow range. In patients with sufficient overlap of propensity scores, adjusted OR ranged from 0.35 (0.04-2.72) to 3.17 (0.31 to 31.9). In patients with insufficient overlap, we consistently found increased odds of death associated with TAVI compared with SAVR irrespective of the method used to control confounding, with adjusted OR ranging from 5.88 (0.67-51.8) to 25.7 (0.88-750). Approximately one third of patients undergoing TAVI were found to be potentially eligible for a randomised comparison of TAVI versus SAVR. CONCLUSIONS Both measured and unmeasured confounding limit the conclusions that can be drawn from observational comparisons of TAVI versus SAVR. Our study indicates that TAVI could be associated with either substantial benefits or harms. Randomised comparisons of TAVI versus SAVR are warranted.

Adherence to patient selection criteria in patients undergoing transcatheter aortic valve implantation with the 18F CoreValve ReValving System

Background: Anecdotal evidence suggests that transcatheter aortic valve implantation (TAVI) is being used beyond pre-market label indications. Methods: To assess the frequency and outcomes associated with “off-label” use of TAVI, we conducted a retrospective study, examining adherence to patient selection criteria in 63 patients undergoing implantation with the 18F CoreValve ReValving System (CRS). Label status (on-label vs off-label) was determined by following (1) inclusion/exclusion criteria indicated in the 18F CRS safety and efficacy trial and (2) a patient selection matrix indicating anatomical boundaries to guide patient selection. Off-label use was defined as the presence of at least one exclusion criterion or “non-acceptable” criteria based on the patient selection matrix. Results: Off-label implantation was identified in 42 patients (67%)—40% had one, 19% had two and 8% had three or more off-label criteria. Baseline demographics were similar between the groups except for a higher logistic EuroSCORE in the on-label group (19.8 (11.2) vs 14.5 (7.3), p = 0.029). There was no significant difference in the procedural success rates between the on-label and off-label groups (91% vs 95%, respectively, p = 0.47). The frequency of angiographic moderate-severe aortic regurgitation, post-implant dilatation or implantation of a second valve was also similar between the groups. At 30 days, the cumulative death rate was 10%; there were four deaths in the “on-label” and three deaths in the “off-label” group. Conclusion: In this study we found that “off-label” implantation of the CRS was common. Further studies are needed to evaluate the consequences of “label status” for patients undergoing TAVI.

Assisted circulation using the Tandemheart®, percutaneous transseptal left ventricular assist device, during percutaneous aortic valve implantation: The Rotterdam experience

AIMS The morbidity and mortality of surgical aortic valve replacement are increased in elderly patients with multiple high risk comorbid conditions. Percutaneous prosthetic aortic valve replacement (PAVR) via the femoral arterial approach is feasible in selected patients, who are poor operative candidates, with satisfactory short term outcomes. It is conceivable that patients with poor LV function may benefit from periprocedural cardio-circulatory support. We evaluated the short-term safety and efficacy of using the TandemHeart PTVA System (p-LVAD) to deliver extracorporeal circulatory support in patients undergoing PAVR. METHODS AND RESULTS Between April 2006 and May 2007 the TandemHeart was used in 10 patients (age: range 64-85, median 80) undergoing elective PAVR using the CoreValve Revalving System. The median (range) time for implementation of circulatory support was 32 (22-40) minutes. A pump flow up to 4.6 L/min was achieved. Systemic haemodynamics were maintained in all but one patient. The median (range) systemic arterial pressure (MBP) was 77 (67-89) mmHg at baseline and 76 (61-91) mmHg after pump functioning. A major systolic blood pressure drop (systolic blood pressure < 70 mmHg, pulse pressure < 10 mmHg, occurred in one patient due to PAVR related pericardial tamponade. Median (range) duration of support was 64 (60-93) minutes. Successful weaning was achieved in all patients. There was one in hospital death. Survival at 12 months was 90%, at 15 months 70%. Vascular access site complications were seen in two patients. One patient suffered a mild to moderate access site bleeding, one a local wound infection. There was no technical device failure. CONCLUSIONS The TandemHeart-PTVA may provide a valuable safeguard during high risk PAVR procedures and enables precise delivery of the CoreValve prosthesis. The rate of device related cardiac and vascular complications was acceptable.

How should I treat acute valve regurgitation

BACKGROUND An 81-year-old male with symptoms of angina and dyspnoea (NYHA 3), a history of coronary bypass surgery, a transaortic peak gradient of 109 mmHg on transthoracic echocardiography and a logistic Euro-SCORE of 21.6 was deemed suboptimal for surgery by a multidisciplinary team and was accepted for TAVI. INVESTIGATION Preprocedural diameter of the native aortic root was 24.4 mm on transthoracic echocardiography (TTE), 26.9 mm on contrast angiography and 26.8 mm by 30.2 mm on multislice computed tomography (MSCT). DIAGNOSIS heavy calcification of the aortic root and coronary arteries by MSCT. TREATMENT Transcatheter aortic calve replacement with an 29 mm CoreValve prosthesis.