Beth Brickham

Transcatheter aortic valve implantation for severe aortic stenosis—a new paradigm for multidisciplinary intervention: A prospective cohort study

BACKGROUND Transcatheter aortic valve implantation (TAVI) is an alternative treatment option for patients with aortic stenosis deemed high risk or unsuitable for aortic valve replacement. The aim of this study was to assess the feasibility of TAVI in elderly patients, the delivery of this technology with a multidisciplinary approach, and the use of traditional surgical scoring systems. METHODS One hundred fifty-one consecutive patients (mean age 82.6 +/- 7.3 years) with severe aortic stenosis underwent TAVI with the Edwards Lifesciences (Irvine, CA) Sapien bioprosthesis using the transapical (n = 84; 56%) or transfemoral (n = 67; 44%) approach from August 2007 to September 2009 at Kings Health Partners, London, United Kingdom. We analyzed procedural outcome, complications, functional status, and midterm outcome of patients. RESULTS The multidisciplinary team comprised interventional cardiologists, cardiothoracic surgeons, imaging specialists, cardiac anesthetists, and specialist nurses. Seventy percent of patients were in New York Heart Association class III/IV, and logistic EuroSCORE was 21.6 +/- 11.9. Procedural success was achieved in 98%. Postoperative complications included stroke (6%), complete atrioventricular block (5.3%), renal failure requiring hemofiltration (9.3%), and vascular injury (8.6%). Overall 30-day mortality was 9.9% (n = 15). The logistic EuroSCORE was a predictor of short-term mortality (logistic regression model, P < .05). Thirty-day mortality post-TAVI for patients with logistic EuroSCORE <20, 20 to 40, and >40 was 5.4%, 13.2%, and 22.2%, respectively. CONCLUSIONS Transcatheter aortic valve implantation is a feasible treatment option in this patient group with promising short/medium-term results. Renal failure is the commonest short-term complication, and the incidence of vascular complications remains high. Risk prediction/case selection remains challenging, and a multidisciplinary team approach appears to be helpful in appropriate patient selection.

Usefulness of periprocedural bleeding to predict outcome after transcatheter aortic valve implantation.

Bleeding is a known predictor of poor outcome after a number of cardiac interventions. We investigated whether using the new bleeding definition of the Valve Academic Research Consortium predicts a poor outcome after transcatheter aortic valve implantation. In addition, we sought to identify those patient characteristics that predict periprocedural bleeding and investigated the effect of blood transfusion. This was a retrospective study of 101 patients undergoing transapical or transfemoral transcatheter aortic valve implantation at Kings College Hospital from August 2007 to November 2010. The association among bleeding, blood transfusion, and in-hospital and 6-month mortality was examined. Of the 101 patients, 5 (4.9%) had life-threatening periprocedural bleeding related to vascular or apical complications, 17 (17%) had major bleeding, and 79 (78%) had minor or no bleeding. The in-hospital mortality rate for the cohort was 9.9% (n = 10) and the 6-month mortality rate was 18.8% (n = 19). Those patients with life-threatening bleeding and those who were transfused had significantly greater in-hospital mortality rates than the patients without life-threatening bleeding or transfusion (60.0% vs 7.3%, p <0.05; and 14.8% vs 4.3%, p <0.05, respectively). Life-threatening bleeding, a decrease in hemoglobin >5 g/dl, and a blood transfusion of >2 U were associated with increased mortality at 6 months. In a logistic regression model, coexisting vascular disease, diabetes, and preprocedural anemia significantly affected the incidence of life-threatening or major bleeding. In conclusion, consistent with many other cardiac interventions, life-threatening periprocedural bleeding after transcatheter aortic valve implantation is associated with poorer outcomes.

Progressive rise in red cell distribution width is associated with poor outcome after transcatheter aortic valve implantation

Objective To investigate the prognostic value of baseline and temporal changes in red cell distribution width (RDW) in patients undergoing transcatheter aortic valve implantation (TAVI). Design Single-centre retrospective observational study. Setting Tertiary cardiac centre. Patients 175 patients undergoing TAVI were included in this study. Main outcome measure Survival. Results We analysed data from 175 TAVI patients (mean (±SD) age 83±7 years, 49% men, mean Logistic EuroSCORE 23±1, 66% preserved left ventricular ejection fraction (LVEF)). Immediately pre-TAVI, mean RDW was 14.6±1.6% with an RDW>15% in 29% of patients. Over median follow-up of 12 months, the median rate of change in RDW was 0.2% per month, and 51 (29%) patients died. On multivariate survival analyses, baseline RDW≥15.5% predicted death (adjusted HR 2.70, 95% CI 1.40 to 5.22, p=0.003) independently of LVEF, transfemoral approach, baseline pulmonary artery systolic pressure, moderate/severe mitral regurgitation and body mass index. A greater rate of increase in RDW over time was associated with increased mortality (adjusted HR 1.11, 95% CI 1.04 to 1.18, p=0.001) independently of baseline RDW and other significant temporal variables including a change in creatinine, bilirubin, mean cell haemoglobin concentration or urea. An increase in RDW>0.1%/month was associated with a twofold increased risk of mortality. Conclusions Baseline RDW≥15.5% and a rising RDW over time strongly correlate to an increased risk of death post-TAVI, and could be used to refine risk stratification. Investigating and ameliorating the causes of RDW expansion may improve survival.

164 Early haemodynamic changes and myocardial injury after transfemoral transcatheter aortic valve implantation (TAVI)

Purpose Transfemoral (TF) TAVI is a novel procedure for the treatment of severe aortic stenosis, without the need for thoracotomy or cardiopulmonary bypass. The procedure results in almost instantaneous normalisation of transvalvular gradients, but little is yet known about the periprocedural haemodynamic effects. We aimed to describe these effects using 3D and tissue Doppler (tD) transthoracic echocardiography (TTE) and Cardiac Output monitoring. Methods In 16 patients undergoing TF TAVI haemodynamics were characterised with a number of tD and 3D TTE measurements. These were taken at multiple time points (baseline, 6 and 24 hours post procedure). Calculated volumetric parameters included 3D end-diastolic volume (EDV) and end-systolic volume (ESV), stroke volume (SV) and 3D LA volume (LAV). Diastolic function was monitored using the indices mean E:E′ and systolic function/contractility was measured with dP/dt max and early peak systolic velocity (S′). The FloTrac system (consisting of the Vigileo monitor and sensor), uses a clinically validated algorithm to provide continuous cardiac output (CO), stroke volume (SV) and systemic vascular resistance in real-time. Results TAVI resulted in an immediate increase in cardiac output (3.7 (baseline), 4.6 (6 h) 4.5 l/min (24 h), p<0.5 baseline vs 6 h and 24 h) with no significant change in systemic vascular resistance (1162, 1292 and 1367 dyn*s/cm5). However, 6 h post-TAVI there was a significant decrease in systolic function as measured by dP/dt max/EDV (see Abstract 164 figure 1A) and co-existent impairment of diastolic function as indicated by medial E:E′ values (see Abstract 164 figure 1B), which was associated with an appropriate increase in LA volume (70.3, 82.6 and 72.8 ml, p<0.05 baseline vs 6 h). Following this, there was a recovery of both systolic and diastolic indices. In addition, another marker of systolic function, S′ increased after 24 h (6.4, 6.6, 8.2 cm/s, p<0.05 baseline vs 24 h and 6 h vs 24 h). Concurrent with this recovery, we observed a significant decrease in EDV and ESV at 24 h post-TAVI (EDV: 94.9 to 83.4 ml (p<0.05); ESV 41.9 to 33.5 ml (p<0.05)). These changes in haemodynamics were associated with significant increase of troponin I levels at 24 h and increase in CK-MB at 6 h after the procedure (troponin: 0.06 vs 1.19 μg/l, p<0.05; CK-MB 1.6 vs 6.6 μg/l, p<0.05).Abstract 164 Figure 1 Conclusion Successful TF TAVI results in an immediate improvement in cardiac output. However, overlying this, within the first 24 h both systolic and diastolic dysfunction occurs. The rise in the markers of myocardial injury suggest this may be due to myocardial stunning and/or some periprocedural myocardial damage. Recovery of contractility is observed after 24 hours.