David Cunningham

Do Outcomes from Transcatheter Aortic Valve Implantation Vary According to Access Route and Valve Type? The UK TAVI Registry

OBJECTIVES To determine whether outcomes from transcatheter aortic valve implantation (TAVI) vary according to access route and valve type in a real-world population. BACKGROUND Registry and uncontrolled trial data have found that patients undergoing nonfemoral TAVI have higher early and late mortality. It is not clear whether worse outcomes relate directly to access route. There have been no direct comparisons of outcomes according to valve type. METHODS Data were collected prospectively on 1,620 patients undergoing TAVI in the UK and compared in 4 groups: SAPIEN transfemoral (TF); SAPIEN transapical (TA); CoreValve TF, CoreValve subclavian. Univariable and multivariable regression analysis was performed to identify independent predictors of mortality. RESULTS Mortality in patients undergoing SAPIEN TAVI via a TA approach was higher than with TF at 30 days (11.2% vs. 4.4%, P < 0.01), 1 year (28.7% vs. 18.1%, P = 0.01), and 2 years (56.0% vs. 43.5%, P = 0.01). Logistic EuroSCORE was higher in TA patients (22.5 ± 12.9% vs. 17.7 ± 11.1%, P < 0.0001). After multivariable analysis TA access was associated with increased mortality at 30 days (OR 2.56, 95% CI 1.46-4.48, P < 0.01) and 2 years (OR 1.75, 1.08-2.74, P = 0.02). There was no significant difference in mortality at any time-point between patients treated with SAPIEN (n = 812) and CoreValve (n = 808) prostheses. CoreValve-treated patients had a higher rate of permanent pacemaker implantation (23.1% vs. 7.2%, P < 0.0001), and grade ≥2 aortic regurgitation on postprocedure echocardiography (13.0% vs. 7.3%, P < 0.01). CONCLUSIONS Patients undergoing TA TAVI experienced increased early and late mortality compared to a TF approach. Survival was not influenced by valve type.

Bleeding in cardiac surgery: The use of aprotinin does not affect survival

OBJECTIVE The antifibrinolytic drug aprotinin has been the most widely used agent to reduce bleeding and its complications in cardiac surgery. Several randomized trials and meta-analyses have demonstrated it to be effective and safe. However, 2 recent reports from a single database have implicated the use of aprotinin as a risk for postoperative complications and reduced long-term survival. METHODS In this single-institution observational study involving 7836 consecutive patients (1998-2006), we assessed the safety of using aprotinin in risk reduction strategy for postoperative bleeding. RESULTS Aprotinin was used in 44% of patients. Multivariate analysis identified aprotinin use in risk reduction for reoperation for bleeding (odds ratio, 0.51; 95% confidence interval, 0.36-0.72; P = .001) and need for blood transfusion postoperatively (odds ratio, 0.67; 95% confidence interval, 0.57-0.79; P = .0002). The use of aprotinin did not affect in-hospital mortality (odds ratio, 1.03; 95% confidence interval, 0.71-1.49; P = 0.73), intermediate-term survival (median follow-up, 3.4 years; range, 0-8.9 years; hazard ratio, 1.09; 95% confidence interval, 0.93-1.28; P = .30), incidence of postoperative hemodialysis (odds ratio, 1.16; 95% confidence interval, 0.73-1.85; P = .49), and incidence of postoperative renal dysfunction (odds ratio, 0.78; 95% confidence interval, 0.59-1.03; P = .07). CONCLUSION This study demonstrates that aprotinin is effective in reducing bleeding after cardiac surgery, is safe, and does not affect short- or medium-term survival.

Trends in 30-day mortality rate and case mix for paediatric cardiac surgery in the UK between 2000 and 2010.

Objectives To explore changes over time in the 30-day mortality rate for paediatric cardiac surgery and to understand the role of attendant changes in the case mix. Methods, setting and participants Included were: all mandatory submissions to the National Institute of Cardiovascular Outcomes Research (NICOR) relating to UK cardiac surgery in patients aged <16 years. The χ2 test for trend was used to retrospectively analyse the proportion of surgical episodes ending in 30-day mortality and with various case mix indicators, in 10 consecutive time periods, from 2000 to 2010. Comparisons were made between two 5-year eras of: 30-day mortality, period prevalence and mean age for 30 groups of specific operations. Main outcome measure 30-day mortality for an episode of surgical management. Results Our analysis includes 36 641 surgical episodes with an increase from 2283 episodes in 2000 to 3939 in 2009 (p<0.01). The raw national 30-day mortality rate fell over the period of review from 4.3% (95% CI 3.5% to 5.1%) in 2000 to 2.6% (95% CI 2.2% to 3.0%) in 2009/2010 (p<0.01). The case mix became more complex in terms of the percentage of patients <2.5 kg (p=0.05), with functionally univentricular hearts (p<0.01) and higher risk diagnoses (p<0.01). In the later time era, there was significant improvement in 30-day mortality for arterial switch with ventricular septal defect (VSD) repair, patent ductus arteriosus ligation, Fontan-type operation, tetralogy of Fallot and VSD repair, and the mean age of patients fell for a range of operations performed in infancy. Conclusions The raw 30-day mortality rate for paediatric cardiac surgery fell over a decade despite a rise in the national case mix complexity, and compares well with international benchmarks. Definitive repair is now more likely at a younger age for selected infants with congenital heart defects.

Death and emergency readmission of infants discharged after interventions for Congenital Heart Disease: a national study of 7643 infants to inform service improvement

Background Improvements in hospital‐based care have reduced early mortality in congenital heart disease. Later adverse outcomes may be reducible by focusing on care at or after discharge. We aimed to identify risk factors for such events within 1 year of discharge after intervention in infancy and, separately, to identify subgroups that might benefit from different forms of intervention. Methods and Results Cardiac procedures performed in infants between 2005 and 2010 in England and Wales from the UK National Congenital Heart Disease Audit were linked to intensive care records. Among 7976 infants, 333 (4.2%) died before discharge. Of 7643 infants discharged alive, 246 (3.2%) died outside the hospital or after an unplanned readmission to intensive care (risk factors were age, weight‐for‐age, cardiac procedure, cardiac diagnosis, congenital anomaly, preprocedural clinical deterioration, prematurity, ethnicity, and duration of initial admission; c‐statistic 0.78 [0.75–0.82]). Of the 7643, 514 (6.7%) died outside the hospital or had an unplanned intensive care readmission (same risk factors but with neurodevelopmental condition and acquired cardiac diagnosis and without preprocedural deterioration; c‐statistic 0.78 [0.75–0.80]). Classification and regression tree analysis were used to identify 6 subgroups stratified by the level (3–24%) and nature of risk for death outside the hospital or unplanned intensive care readmission based on neurodevelopmental condition, cardiac diagnosis, congenital anomaly, and duration of initial admission. An additional 115 patients died after planned intensive care admission (typically following elective surgery). Conclusions Adverse outcomes in the year after discharge are of similar magnitude to in‐hospital mortality, warrant service improvements, and are not confined to diagnostic groups currently targeted with enhanced monitoring.

Activity and outcomes for aortic valve implantations performed in England and Wales since the introduction of transcatheter aortic valve implantation

OBJECTIVES The first transcatheter aortic valve implantation (TAVI) in England and Wales was performed in 2007. This study presents the subsequent national activity and outcomes for both TAVI and aortic valve replacement (AVR). METHODS Data for all AVR and TAVI procedures between January 2006 and December 2012 in England and Wales were included. The number of procedures, patient characteristics, in-hospital and 30-day mortality, postoperative length of stay (PLOS) and survival were analysed separately for: isolated AVR; AVR + coronary artery bypass graft (CABG) surgery; AVR + other surgery and TAVI. RESULTS The number of TAVIs increased from 66 in 2007 (0.8% of all implants) to 1186 in 2012 (10.9% of all implants). AVR activity also increased over the study period. TAVI patients were older and had a higher mean logistic EuroSCORE than all AVR groups. The 30-day mortality rates were 2.1% for isolated AVR, 3.9% for AVR + CABG, 7.7% for AVR + other surgery and 6.2% for TAVI. In-hospital mortality has significantly improved for all groups. The 5-year survival rates were 82.6% for isolated AVR, 81.7% for AVR + CABG, 74.5% for AVR + other surgery and 46.1% for TAVI. The median PLOS after TAVI was similar to that of isolated AVR but shorter than that of the other AVR groups. CONCLUSIONS Since the introduction of TAVI, there has been an increase in both TAVI and AVR activity. TAVIs now represent over 10% of all aortic valve implants. There are distinct differences between procedural groups with respect to patient risk factors. Outcomes for all procedural groups have improved, but long-term TAVI results are required before its role in the treatment of aortic stenosis can be fully defined.

Surgeon length of service and risk-adjusted outcomes: linked observational analysis of the UK National Adult Cardiac Surgery Audit Registry and General Medical Council Register.

Summary Objectives To explore the relationship between in-hospital mortality following adult cardiac surgery and the time since primary clinical qualification for the responsible consultant cardiac surgeon (a proxy for experience). Design Retrospective analysis of prospectively collected national registry data over a 10-year period using mixed-effects multiple logistic regression modelling. Surgeon experience was defined as the time between the date of surgery and award of primary clinical qualification. Setting UK National Health Service hospitals performing cardiac surgery between January 2003 and December 2012. Participants All patients undergoing coronary artery bypass grafts and/or valve surgery under the care of a consultant cardiac surgeon. Main outcome measures All-cause in-hospital mortality. Results A total of 292,973 operations performed by 273 consultant surgeons (with lengths of service from 11.2 to 42.0 years) were included. Crude mortality increased approximately linearly until 33 years service, before decreasing. After adjusting for case-mix and year of surgery, there remained a statistically significant (p = 0.002) association between length of service and in-hospital mortality (odds ratio 1.013; 95% CI 1.005–1.021 for each year of ‘experience’). Conclusions Consultant cardiac surgeons take on increasingly complex surgery as they gain experience. With this progression, the incidence of adverse outcomes is expected to increase, as is demonstrated in this study. After adjusting for case-mix using the EuroSCORE, we observed an increased risk of mortality in patients operated on by longer serving surgeons. This finding may reflect under-adjustment for risk, unmeasured confounding or a real association. Further research into outcomes over the time course of surgeons careers is required.

Patient reported outcome measures for cardiac ablation procedures: a multicentre pilot to develop a new questionnaire

Aim To assess the feasibility of administering Patient Reported Outcomes Measures (PROMs) in patients treated with ablation for cardiac arrhythmias, and to conduct the first stage of development and testing of a new PROM tool. Methods and results A new tool was developed by a multidisciplinary team and tested alongside an adaptation of the patient perception of arrhythmia questionnaire (PPAQ) and EQ-5D-5L in a multicentre retrospective audit involving 791 consecutive cardiac arrhythmia patients treated with catheter ablation at three UK centres over 13 months. Data were recorded in the National Cardiac Rhythm Management Database, part of the National Institute for Cardiovascular Outcomes Research. The response rate was 71.9% (n = 569). Patients reported significant improvements across all outcomes and impacts, with reductions in symptoms of 51.7% (heart racing), 33.9% (fatigue) 31.8% (heart flutters), 43.5% (dizziness), 38.6% (breathlessness), 44.2% (chest pressure), 33.1% (trouble concentrating), 15.9% (headache), 28.3% (neck pressure), and 23.4% (fainting) (P < 0.001). The mean number of social days affected reduced by 7.49 days/month (P < 0.001); mean work/school days affected/month reduced by 6.26 (P < 0.001); mean GP/hospital visits reduced by 1.36 days/month (P < 0.001). The procedure met patient expectations in 72% of responders. Conclusions The high response rate suggests that the use of PROMs in this patient group is feasible, with rates equalling those of the National PROMs Programme. The results showed that patients experienced significant improvements in their quality of life following ablation, while feedback allowed the tools to be improved. Further work is required to validate these tools; however, the findings suggest that PROMs could be useful in the audit of ablation techniques.

Ethnic and socioeconomic variation in incidence of congenital heart defects

Introduction Ethnic differences in the birth prevalence of congenital heart defects (CHDs) have been reported; however, studies of the contemporary UK population are lacking. We investigated ethnic variations in incidence of serious CHDs requiring cardiac intervention before 1 year of age. Methods All infants who had a cardiac intervention in England and Wales between 1 January 2005 and 31 December 2010 were identified in the national congenital heart disease surgical audit and matched with paediatric intensive care admission records to create linked individual child records. Agreement in reporting of ethnic group by each audit was evaluated. For infants born 1 January 2006 to 31 December 2009, we calculated incidence rate ratios (IRRs) for CHDs by ethnicity and investigated age at intervention, antenatal diagnosis and area deprivation. Results We identified 5350 infants (2940 (55.0%) boys). Overall CHD incidence was significantly higher in Asian and Black ethnic groups compared with the White reference population (incidence rate ratios (IRR) (95% CIs): Asian 1.5 (1.4 to 1.7); Black 1.4 (1.3 to 1.6)); incidence of specific CHDs varied by ethnicity. No significant differences in age at intervention or antenatal diagnosis rates were identified but affected children from non-White ethnic groups were more likely to be living in deprived areas than White children. Conclusions Significant ethnic variations exist in the incidence of CHDs, including for specific defects with high infant mortality. It is essential that healthcare provision mitigates ethnic disparity, including through timely identification of CHDs at screening, supporting parental choice and effective interventions. Future research should explore the factors underlying ethnic variation and impact on longer-term outcomes.

The United Kingdom National Congenital Heart Disease Audit

The National Congenital Heart Disease Audit was set up as a validated electronic database in 2000 for quality assurance purposes to assess and monitor outcomes after therapeutic procedures on patients with paediatric and congenital heart disease of all ages, with over 100,000 patients currently in the database (60 % post-surgery). Mortality is tracked independently by using unique patient identifiers (NHS number). NICOR has published centre specific comparisons of activity, data quality and survival on its public portal following individual procedures for over a decade, including when units have appeared to be underperforming (web.nicor.org.uk). It now also operates at a local level with onsite near real time monitoring of 30 day mortality and re-interventions. NICOR has begun to publish risk adjusted whole centre comparative outcomes, both using novel risk adjustment methodology developed using the Audit’s database. The Audit has been instrumental in improving the prenatal detection of major congenital heart malformations by publishing the regional success rates of antenatal screening.

G166 Risk of death or emergency readmission following discharge after infant cardiac intervention for congenital heart disease

Aims 1) To identify risk factors for death or unplanned readmission within one year following hospital discharge after cardiac intervention for congenital heart disease. 2) To characterise patient groups at highest risk who would benefit from targeted intervention. Methods Records in the national congenital cardiac surgical audit (NICOR) pertaining to UK infants who had a cardiac surgery or intervention aged under 12 months between 01/01/2005 and 31/12/2010 were matched with intensive care admission records in Paediatric Intensive Care Audit Network (PICANET); linked records with known life-status were obtained for 7634 infants. Outcome measures were: Outcome 1 – death within 1-year following discharge; Outcome 2 – Outcome 1 or emergency readmission to PICU within 1-year following discharge. Potential risk factors available from either dataset were pre-specified and univariate and multivariate logistic regression used to investigate the effects of these on each outcome. Classification and regression tree (CART) analysis was used to identify distinct patient groups differentiated by risk of Outcome 2, each defined by a set of patient characteristics. Results 3.2% (246/7643) and 6.7% (514/7643) of infants experienced Outcome 1 and 2 respectively. Fitted multivariate models for both outcomes were robust in risk factor selection (Outcome 1 - ROC AUC = 0.78, 95% CI [0.75, 0.82]; Outcome 2 - ROC AUC = 0.78 [0.75, 0.80]). Risk factors significant in the multivariate Outcome 2 model were: age at procedure, weight z-score, cardiac procedure, cardiac diagnosis, non-cardiac congenital anomaly, neurodevelopmental condition, prematurity (<37 weeks gestation), ethnicity, and length of stay in specialist centre (LOS). Clinical deterioration was additionally significant to Outcome 1 whilst neurodevelopmental condition and acquired diagnoses were not. Key defining characteristics of infants in the patient groups identified as higher risk were [% Outcome 2]: (1) neurodevelopmental conditions [24%]; (2) Hypoplastic left heart, single ventricle or pulmonary atresia [15%]; (3) Congenital anomalies and LOS > 1 month [24% risk]; (4) No congenital anomalies and LOS > 1 month [9% risk]. Conclusions Understanding patient risk groups should inform recommendations for improving services, support development of interventions to mitigate each profile of risk and facilitate evaluation of the priority and feasibility of targeting each group.