Fiona Walker
University College London
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European Heart Journal | 2011
Vera Regitz-Zagrosek; Carina Blomström Lundqvist; Claudio Borghi; Renata Cifkova; Rafael Ferreira; Jean-Michel Foidart; J. Simon R. Gibbs; Christa Gohlke-Baerwolf; Bulent Gorenek; Bernard Iung; Mike Kirby; Angela H. E. M. Maas; Joao Morais; Petros Nihoyannopoulos; Petronella G. Pieper; Patrizia Presbitero; Jolien W. Roos-Hesselink; Maria Schaufelberger; Ute Seeland; Lucia Torracca; Jeroen Bax; Angelo Auricchio; Helmut Baumgartner; Claudio Ceconi; Veronica Dean; Christi Deaton; Robert Fagard; Christian Funck-Brentano; David Hasdai; Arno W. Hoes
Table 1. Classes of recommendation Table 2. Levels of evidence Table 3. Estimated fetal and maternal effective doses for various diagnostic and interventional radiology procedures Table 4. Predictors of maternal cardiovascular events and risk score from the CARPREG study Table 5. Predictors of maternal cardiovascular events identified in congential heart diseases in the ZAHARA and Khairy study Table 6. Modified WHO classification of maternal cardiovascular risk: principles Table 7. Modified WHO classification of maternal cardiovascular risk: application Table 8. Maternal predictors of neonatal events in women with heart disease Table 9. General recommendations Table 10. Recommendations for the management of congenital heart disease Table 11. Recommendations for the management of aortic disease Table 12. Recommendations for the management of valvular heart disease Table 13. Recommendations for the management of coronary artery disease Table 14. Recommendations for the management of cardiomyopathies and heart failure Table 15. Recommendations for the management of arrhythmias Table 16. Recommendations for the management of hypertension Table 17. Check list for risk factors for venous thrombo-embolism Table 18. Prevalence of congenital thrombophilia and the associated risk of venous thrombo-embolism during pregnancy Table 19. Risk groups according to risk factors: definition and preventive measures Table 20. Recommendations for the prevention and management of venous thrombo-embolism in pregnancy and puerperium Table 21. Recommendations for drug use ABPM : ambulatory blood pressure monitoring ACC : American College of Cardiology ACE : angiotensin-converting enzyme ACS : acute coronary syndrome AF : atrial fibrillation AHA : American Heart Association aPTT : activated partial thromboplastin time ARB : angiotensin receptor blocker AS : aortic stenosis ASD : atrial septal defect AV : atrioventricular AVSD : atrioventricular septal defect BMI : body mass index BNP : B-type natriuretic peptide BP : blood pressure CDC : Centers for Disease Control CHADS : congestive heart failure, hypertension, age (>75 years), diabetes, stroke CI : confidence interval CO : cardiac output CoA : coarction of the aorta CT : computed tomography CVD : cardiovascular disease DBP : diastolic blood pressure DCM : dilated cardiomyopathy DVT : deep venous thrombosis ECG : electrocardiogram EF : ejection fraction ESC : European Society of Cardiology ESH : European Society of Hypertension ESICM : European Society of Intensive Care Medicine FDA : Food and Drug Administration HCM : hypertrophic cardiomyopathy ICD : implantable cardioverter-defibrillator INR : international normalized ratio i.v. : intravenous LMWH : low molecular weight heparin LV : left ventricular LVEF : left ventricular ejection fraction LVOTO : left ventricular outflow tract obstruction MRI : magnetic resonance imaging MS : mitral stenosis NT-proBNP : N-terminal pro B-type natriuretic peptide NYHA : New York Heart Association OAC : oral anticoagulant PAH : pulmonary arterial hypertension PAP : pulmonary artery pressure PCI : percutaneous coronary intervention PPCM : peripartum cardiomyopathy PS : pulmonary valve stenosis RV : right ventricular SBP : systolic blood pressure SVT : supraventricular tachycardia TGA : complete transposition of the great arteries TR : tricuspid regurgitation UFH : unfractionated heparin VSD : ventricular septal defect VT : ventricular tachycardia VTE : venous thrombo-embolism WHO : World Health Organization Guidelines summarize and evaluate all available evidence, at the time of the writing process, on a particular issue with the aim of assisting physicians in selecting the best management strategies for an individual patient, with a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines are no substitutes but are complements for textbooks and cover the European Society of Cardiology (ESC) Core Curriculum topics. Guidelines and recommendations should help the …
Circulation | 2008
Philipp Lurz; Louise Coats; Sachin Khambadkone; Johannes Nordmeyer; Younes Boudjemline; Silvia Schievano; Vivek Muthurangu; Twin Yen Lee; Giovanni Parenzan; Graham Derrick; Seamus Cullen; Fiona Walker; Victor Tsang; John E. Deanfield; Andrew M. Taylor; Philipp Bonhoeffer
Background— Percutaneous pulmonary valve implantation was introduced in the year 2000 as a nonsurgical treatment for patients with right ventricular outflow tract dysfunction. Methods and Results— Between September 2000 and February 2007, 155 patients with stenosis and/or regurgitation underwent percutaneous pulmonary valve implantation. This led to significant reduction in right ventricular systolic pressure (from 63±18 to 45±13 mm Hg, P<0.001) and right ventricular outflow tract gradient (from 37±20 to 17±10 mm Hg, P<0.001). Follow-up ranged from 0 to 83.7 months (median 28.4 months). Freedom from reoperation was 93% (±2%), 86% (±3%), 84% (±4%), and 70% (±13%) at 10, 30, 50, and 70 months, respectively. Freedom from transcatheter reintervention was 95% (±2%), 87% (±3%), 73% (±6%), and 73% (±6%) at 10, 30, 50, and 70 months, respectively. Survival at 83 months was 96.9%. On time-dependent analysis, the first series of 50 patients (log-rank test P<0.001) and patients with a residual gradient >25 mm Hg (log-rank test P=0.01) were associated with a higher risk of reoperations. Conclusions— Percutaneous pulmonary valve implantation resulted in the ability to avoid surgical right ventricular outflow tract revision in the majority of cases. This procedure might reduce the number of operations needed over the total lifetime of patients with right ventricle–to–pulmonary artery conduits.
Circulation | 2008
Alessandra Frigiola; Victor Tsang; Catherine Bull; Louise Coats; Sachin Khambadkone; Graham Derrick; Bryan Mist; Fiona Walker; Carin van Doorn; Philipp Bonhoeffer; Andrew M. Taylor
Background— The timing of pulmonary valve replacement (PVR) for free pulmonary incompetence in patients with congenital heart disease remains a dilemma for clinicians. We wanted to assess the determinants of improvement after PVR for pulmonary regurgitation over a wide range of patient ages and to use any identified predictors to compare clinical outcomes between patient groups. Methods and Results— Seventy-one patients (mean age 22±11 years; range, 8.5 to 64.9; 72% tetralogy of Fallot) underwent PVR for severe pulmonary regurgitation. New York Heart Association class improved after PVR (median of 2 to 1, P<0.0001). MRI and cardiopulmonary exercise testing were performed before and 1 year after intervention. After PVR, there was a significant reduction in right ventricular volumes (end diastolic volume 142±43 to 91±18, end systolic volume 73±33 to 43±14 mL/m2, P<0.0001), whereas left ventricular end diastolic volume increased (66±12 to 73±13 mL/m2, P<0.0001). Effective cardiac output significantly increased (right ventricular: 3.0±0.8 to 3.3±0.8 L/min, P=0.013 and left ventricular: 3.0±0.6 to 3.4±0.7 L/min, P<0.0001). On cardiopulmonary exercise testing, ventilatory response to carbon dioxide production at anaerobic threshold improved from 35.9±5.8 to 34.1±6.2 (P=0.008). Normalization of ventilatory response to carbon dioxide production was most likely to occur when PVR was performed at an age younger than 17.5 years (P=0.013). Conclusions— A relatively aggressive PVR policy (end diastolic volume <150 mL/m2) leads to normalization of right ventricular volumes, improvement in biventricular function, and submaximal exercise capacity. Normalization of ventilatory response to carbon dioxide production is most likely to occur when surgery is performed at an age ≤17.5 years. This is also associated with a better left ventricular filling and systolic function after surgery.
Journal of the American College of Cardiology | 2011
Philipp Lurz; Johannes Nordmeyer; Alessandro Giardini; Sachin Khambadkone; Vivek Muthurangu; Silvia Schievano; Jean-Benoit Thambo; Fiona Walker; Seamus Cullen; Graham Derrick; Andrew M. Taylor; Philipp Bonhoeffer
OBJECTIVES The purpose of this study was to assess the potential of late positive functional remodeling after percutaneous pulmonary valve implantation (PPVI) in right ventricular outflow tract dysfunction. BACKGROUND PPVI has been shown to impact acutely on biventricular function and exercise performance, but the potential for further late functional remodeling remains unknown. METHODS Sixty-five patients with sustained hemodynamic effects of PPVI at 1 year were included. Patients were divided into 2 subgroups based on pre-procedural predominant pulmonary stenosis (PS) (n = 35) or predominant pulmonary regurgitation (PR) (n = 30). Data from magnetic resonance imaging and cardiopulmonary exercise testing were compared at 3 time points: before PPVI, within 1 month (early) and at 12 months (late) after PPVI. RESULTS There was a significant decrease in right ventricle end-diastolic volume early after PPVI in both subgroups of patients. Right ventricle ejection fraction improved early only in the PS group (51 ± 11% vs. 58 ± 11% and 51 ± 12% vs. 50 ± 11%, p < 0.001 for PS, p = 0.13 for PR). Late after intervention, there were no further changes in magnetic resonance parameters in either group (right ventricle ejection fraction, 58 ± 11% in the PS group and 52 ± 11% in the PR group, p = 1.00 and p = 0.13, respectively). In the PS group at cardiopulmonary exercise testing, there was a significant improvement in peak oxygen uptake early (24 ± 8 ml/kg/min vs. 27 ± 9 ml/kg/min, p = 0.008), with no further significant change late (27 ± 9 ml/kg/min, p = 1.00). In the PR group, no significant changes in peak oxygen uptake from early to late could be demonstrated (25 ± 8 ml/kg/min vs. 25 ± 8 ml/kg/min vs. 26 ± 9 ml/kg/min, p = 0.48). CONCLUSIONS In patients with a sustained hemodynamic result 1 year after PPVI, a prolonged phase of maintained cardiac function is observed. However, there is no evidence for further positive functional remodeling beyond the acute effects of PPVI.
Haematologica | 2009
John Quinn; Kate Von Klemperer; Ruth Brooks; Donald Peebles; Fiona Walker; Hannah Cohen
This report describes the successful use of dose-escalating low molecular weight heparin thrombo-profylaxis in pregnant women with prosthetic heart valves. The use of standard dose low molecular weight heparin (LMWH) to anticoagulate women with mechanical valves in pregnancy is associated with morbidity and mortality. We conducted a prospective audit of the use of adjusted dose high intensity LMWH in 12 pregnancies in 11 women with prosthetic heart valves. LMWH ± low-dose aspirin was started at therapeutic-dose with monitoring of anti-Xa levels to achieve a target level of 1.0–1.2 IU/mL (0.8–1.2 in the first 3/12 pregnancies). This necessitated a mean increase in the dose of LMWH of 54.4% (SD±33.2) over initial dose. Eleven of 12 pregnancies resulted in live births, with one intrauterine fetal death at 37 weeks. One non-fatal valve thrombosis occurred at 26 weeks gestation associated with subtherapeutic anti-Xa levels. Three patients experienced major bleeding. This regime provides a therapeutic option for women with mechanical heart valves during pregnancy, provided anti-Xa levels are kept within the target range. These patients require close surveillance for bleeding and thrombotic complications within a multi-disciplinary setting.
Circulation | 2007
Dominic Abrams; Mark J. Earley; Simon Sporton; Peter M. Kistler; Michael A. Gatzoulis; Michael Mullen; Janice A. Till; Seamus Cullen; Fiona Walker; Martin Lowe; John E. Deanfield; Richard J. Schilling
Background— The right atrium late after the Fontan procedure is characterized by multiple complex arrhythmia circuits. We performed simultaneous electroanatomic and noncontact mapping to assess the accuracy of both systems to identify scar and arrhythmia. Methods and Results— Mapping was performed in 26 patients aged 26.8±8.9 years, 18.7±4.4 years after Fontan surgery. The area and site of abnormal endocardium defined by electroanatomic mapping (bipolar contact electrogram <0.5 mV) were compared with those defined by noncontact mapping during sinus rhythm and by dynamic substrate mapping. Contact and reconstructed unipolar electrograms at a known distance from the multielectrode array, recorded by the noncontact system simultaneously at 452 endocardial sites, were compared for morphological cross correlation, timing difference, and amplitude. Mapping of arrhythmias was performed with both systems when possible. The median patient abnormal endocardium as defined by electroanatomic mapping covered 38.0% (range 16.7% to 97.8%) of the right atrial surface area, as opposed to 60.9% (range 21.3% to 98.5%) defined by noncontact mapping during sinus rhythm and 11.9% (range 0.4% to 67.3%) by dynamic substrate mapping. A significant decrease in electrogram cross correlation (P=0.003), timing (P=0.012), and amplitude (P=0.003) of reconstructed electrograms, but not of contact electrograms (P=0.742), was seen at endocardial sites >40 mm from the multielectrode array. Successful arrhythmia mapping by electroanatomic versus noncontact mapping was superior in 15 patients (58%), the same in 6 (23%), and inferior in 5 (19%; P=0.044). Conclusions— Electroanatomic mapping is the superior modality for arrhythmia mapping late after the Fontan procedure. Noncontact mapping is limited by a significant reduction in reconstructed electrogram correlation, timing, and amplitude >40 mm from the multielectrode array and cannot accurately define areas of scar and low-voltage endocardium.
European Heart Journal | 2010
Matthias Greutmann; Katherine Von Klemperer; Ruth Brooks; Donald Peebles; Patrick O'Brien; Fiona Walker
AIMS To determine pregnancy outcome and risk factors for adverse events in women with congenital heart disease (CHD) and residual haemodynamic right ventricular (RV) outflow tract (RVOT) lesions. METHODS AND RESULTS Pregnancy outcome data for women with CHD and residual RVOT lesions have been recorded since 2001. There were 76 pregnancies in 47 women that continued beyond 24 weeks gestation. At conception 20% had RVOT obstruction, 32% had pulmonary regurgitation (PR) and 49% had mixed RVOT obstruction and PR. Moderate-to-severe PR was present in 30 (39%) and RVOT obstruction > or =30 mmHg in 12 (16%) of pregnancies. Seven pregnancies (9%) were complicated by right heart failure (RHF). No arrhythmias were documented. Predictors for RHF were moderate-to-severe PR in combination with at least one additional risk factor (twin pregnancy, branch pulmonary artery stenosis, RV systolic dysfunction, RV hypertrophy). All patients responded to diuretic treatment and had a good pregnancy outcome without foetal complications. CONCLUSION In patients with CHD and residual RVOT lesions, the outcome of pregnancy is good. Patients with moderate-to-severe PR were at risk for symptomatic RHF only if additional risk factors were present. When treated by a multidisciplinary team, maternal and foetal outcome was good. The general recommendation that pulmonary valve replacement should be undertaken prior to pregnancy in patients with moderate-to-severe PR and RV dilatation needs to be reconsidered.
Heart | 2010
Rajesh Puranik; Victor Tsang; Andrew Broadley; Johannes Nordmeyer; Phillip Lurz; Nagarajan Muthialu; Graham Derrick; Fiona Walker; Seamus Cullen; Marc R. de Leval; Phillip Bonhoeffer; Andrew M. Taylor; Vivek Muthurangu
Objective To assess autograft, homograft and ventricular function, as well as exercise capacity, in adult patients who have undergone the Ross procedure. Setting Single centre paediatric and adult congenital heart disease unit. Patients 45 subjects (24.6 years, range 16.9–52.2 years) who underwent the Ross procedure between 1994 and 2006 (8.1 years after the Ross operation, range 2.0–14.0 years). Interventions Cardiovascular magnetic resonance imaging, echocardiography and cardiopulmonary exercise testing. Main outcome measures Autograft and homograft stenosis, and regurgitation. Autograft size. Biventricular function, scar volume and exercise capacity. Results Mean autograft regurgitation was 6.8%±8.3% (trivial regurgitation) and diameter was 40.0±7.0 mm. Mean homograft velocity was 2.4±0.6 m/s (mild-moderate stenosis) and regurgitation was 6.1%±8.3% (trivial regurgitation). Biventricular systolic function was normal (LV EF 63.1±6.4% and RV EF 60.1%±7.6%). In 38% of cases there was evidence of LV scar, mostly noted within the inter-ventricular septum. The mean exercise capacity achieved was 87%±22% of predicted. There was no correlation between exercise capacity and ventricular function or scar. Conclusion This study demonstrates minor autograft and homograft dysfunction in the majority of patients after the Ross procedure, associated with good ventricular function and exercise capacity. In addition, minor scar was present in a third of patients with no functional consequences.
The Journal of Thoracic and Cardiovascular Surgery | 2009
Johannes Nordmeyer; Philipp Lurz; Victor Tsang; Louise Coats; Fiona Walker; Andrew M. Taylor; Sachin Khambadkone; Marc R. de Leval; Philipp Bonhoeffer
OBJECTIVE The Ross procedure offers good autograft function and low reoperation rates for the neoaortic valve; however, the rate of conduit dysfunction in the right ventricular outflow tract remains a concern. This study assessed percutaneous pulmonary valve implantation in this setting. METHODS We retrospectively analyzed outcomes of 12 patients (mean age 28 +/- 5 years) referred for percutaneous pulmonary valve implantation to treat right ventricle-pulmonary artery conduit failure 11.1 +/- 3.3 years after Ross procedure. RESULTS Percutaneous pulmonary valve implantation was feasible in all 12 patients, with no procedural complications (procedure time 99 +/- 16 minutes, fluoroscopy time 21 +/- 6 minutes). Right ventricular outflow tract gradient during catheterization and pulmonary regurgitant fraction on magnetic resonance imaging fell after valve implantation (gradient 34 +/- 6 to 14 +/- 3 mm Hg, P < .01, regurgitant fraction 20% +/- 6% to 2% +/- 1%, P < .05). After restoration of right ventricular outflow tract function, indexed right ventricular end-diastolic volume decreased (91 +/- 13 to 78 +/- 12 mL x beat(-1) x m(-2), P < .01) and maximal cardiopulmonary exercise performance improved (peak oxygen consumption 25.4 +/- 2.3 to 30.8 +/- 3.0 mL x kg(-1) x min(-1), P < .01). During follow-up (18.8 +/- 4.6 months), there was 1 device explantation (restenosis). The probabilities of freedom from right ventricular outflow tract reoperation were 100% at 1 year and 90% at 3 years. CONCLUSIONS Percutaneous pulmonary valve implantation provides an effective transcatheter treatment strategy to prolong the lifespan of right ventricle-pulmonary artery conduits after the Ross procedure, reducing the reoperation burden on patients with aortic valve disease.
Europace | 2012
Pia K. Schuler; Anna S Herrey; Angie Wade; Ruth Brooks; Donald Peebles; Pier D. Lambiase; Fiona Walker
AIMS With improved survival of patients with congenital and inherited heart disease, there is now a younger cohort of patients with an implantable cardioverter defibrillator (ICD) for the prevention and treatment of ventricular dysrrhythmias. Young women with such disorders often wish to embark on pregnancy, but pregnancy outcome data for this group is sparse. We therefore evaluated pregnancy outcome in patients with heart disease and an ICD in situ. METHODS AND RESULTS A retrospective analysis was performed on all women with an ICD in situ, who had pregnancy care provided by the specialist maternal cardiology service at University College London Hospitals. Data for 19 pregnancies in 14 women were collected. The underlying cardiac diagnoses were congenital heart disease (one), familial hypertrophic cardiomyopathy (eight), familial dilated cardiomyopathy (one), inherited long QT syndrome (one), and idiopathic cardiac arrest (one). Three women had moderate impairment of the left ventricular systolic function (ejection fraction <45%), in the remainder it was normal. Nine ICD implants were for primary prevention of sudden cardiac death (64%) and five for secondary prevention (36%). Of the 19 pregnancies, 18 continued beyond 24 weeks gestation with 18 live births. In eight pregnancies there were medical or device-related complications (42.9%) as follows: arrhythmias (four) (21.1%), heart failure (two) (9.1%), ICD shocks (one) (5.3%), atrial lead fracture (one) (5.3%), and lead-related thrombus (one) (5.3%). There were no inappropriate device shocks or therapies. CONCLUSIONS Women with heart disease and an ICD implant can have a good outcome during pregnancy but medical and device complications are not uncommon.