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Afoke J, Mohal J, Kanaganayagam GS, Casula R, Bruno V, Howard L, Gibbs S, Punjabi P. Cardiopulmonary exercise testing augments watchful waiting in asymptomatic severe primary mitral regurgitation. Perfusion 2023:2676591231207735. [PMID: 37851335 DOI: 10.1177/02676591231207735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
INTRODUCTION Our aim is to describe the use of cardiopulmonary exercise testing in watchful waiting for asymptomatic severe primary mitral regurgitation. METHODS Between October 2016 and October 2017, ten patients with asymptomatic severe primary mitral regurgitation underwent watchful waiting in a single centre. Baseline assessment included history, physical examination, transthoracic echocardiogram and cardiopulmonary exercise testing. Patients were re-evaluated every 6 months with history, physical examination and transthoracic echocardiogram; and at 12 months with cardiopulmonary exercise testing. RESULTS At 1 year follow up, five patients remained asymptomatic with no significant change in left ventricular ejection fraction (p = 0.18). This was associated with no significant change in cardiopulmonary exercise testing parameters. However, five patients developed early new symptoms or changes in echocardiographic parameters with a significant fall in left ventricular ejection fraction (p < 0.01). This was associated with a significant fall in anaerobic threshold (p = 0.04) and four of the five patients having an abnormal percentage predicted peak VO2 at 1 year follow up. CONCLUSIONS Changes in symptomatic status or echocardiographic parameters during a watchful waiting approach for asymptomatic severe primary mitral regurgitation is associated with a significant reduction in cardiopulmonary exercise testing parameters.
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Affiliation(s)
- Jonathan Afoke
- Department of Cardiothoracic Surgery, Imperial College Healthcare NHS Trust, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Jagdeep Mohal
- National Heart and Lung Institute, Imperial College, London, UK
| | | | - Roberto Casula
- Department of Cardiothoracic Surgery, Imperial College Healthcare NHS Trust, London, UK
| | - Vito Bruno
- Department of Minimally Invasive Cardiac Surgery, IRCCS Galeazzi, Sant'Ambrogio Hospital, Milan, Italy
| | - Luke Howard
- Department of Cardiothoracic Surgery, Imperial College Healthcare NHS Trust, London, UK
| | - Simon Gibbs
- National Heart and Lung Institute, Imperial College, London, UK
| | - Prakash Punjabi
- Department of Cardiothoracic Surgery, Imperial College Healthcare NHS Trust, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
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Raphael CE, Mitchell F, Kanaganayagam GS, Liew AC, Di Pietro E, Vieira MS, Kanapeckaite L, Newsome S, Gregson J, Owen R, Hsu LY, Vassiliou V, Cooper R, Mrcp AA, Ismail TF, Wong B, Sun K, Gatehouse P, Firmin D, Cook S, Frenneaux M, Arai A, O'Hanlon R, Pennell DJ, Prasad SK. Cardiovascular magnetic resonance predictors of heart failure in hypertrophic cardiomyopathy: the role of myocardial replacement fibrosis and the microcirculation. J Cardiovasc Magn Reson 2021; 23:26. [PMID: 33685501 PMCID: PMC7941878 DOI: 10.1186/s12968-021-00720-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 12/10/2020] [Accepted: 01/31/2021] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION Heart failure (HF) in hypertrophic cardiomyopathy (HCM) is associated with high morbidity and mortality. Predictors of HF, in particular the role of myocardial fibrosis and microvascular ischemia remain unclear. We assessed the predictive value of cardiovascular magnetic resonance (CMR) for development of HF in HCM in an observational cohort study. METHODS Serial patients with HCM underwent CMR, including adenosine first-pass perfusion, left atrial (LA) and left ventricular (LV) volumes indexed to body surface area (i) and late gadolinium enhancement (%LGE- as a % of total myocardial mass). We used a composite endpoint of HF death, cardiac transplantation, and progression to NYHA class III/IV. RESULTS A total of 543 patients with HCM underwent CMR, of whom 94 met the composite endpoint at baseline. The remaining 449 patients were followed for a median of 5.6 years. Thirty nine patients (8.7%) reached the composite endpoint of HF death (n = 7), cardiac transplantation (n = 2) and progression to NYHA class III/IV (n = 20). The annual incidence of HF was 2.0 per 100 person-years, 95% CI (1.6-2.6). Age, previous non-sustained ventricular tachycardia, LV end-systolic volume indexed to body surface area (LVESVI), LA volume index ; LV ejection fraction, %LGE and presence of mitral regurgitation were significant univariable predictors of HF, with LVESVI (Hazard ratio (HR) 1.44, 95% confidence interval (95% CI) 1.16-1.78, p = 0.001), %LGE per 10% (HR 1.44, 95%CI 1.14-1.82, p = 0.002) age (HR 1.37, 95% CI 1.06-1.77, p = 0.02) and mitral regurgitation (HR 2.6, p = 0.02) remaining independently predictive on multivariable analysis. The presence or extent of inducible perfusion defect assessed using a visual score did not predict outcome (p = 0.16, p = 0.27 respectively). DISCUSSION The annual incidence of HF in a contemporary ambulatory HCM population undergoing CMR is low. Myocardial fibrosis and LVESVI are strongly predictive of future HF, however CMR visual assessment of myocardial perfusion was not.
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Affiliation(s)
- Claire E Raphael
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.
- Department of CMR, Royal Brompton Hospital, Sydney Street, Sydney, SW3 6NP, UK.
| | - Frances Mitchell
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | | | - Alphonsus C Liew
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Elisa Di Pietro
- Department of Advanced Biomedical Sciences, University of Naples, Naples, Italy
| | - Miguel Silva Vieira
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Lina Kanapeckaite
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Simon Newsome
- London School of Hygiene & Tropical Medicine, London, UK
| | - John Gregson
- London School of Hygiene & Tropical Medicine, London, UK
| | - Ruth Owen
- London School of Hygiene & Tropical Medicine, London, UK
| | - Li-Yueh Hsu
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Vassilis Vassiliou
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
- Norwich Medical School, University of East Anglia, Norwich, UK
| | - Robert Cooper
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Aamir Ali Mrcp
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Tevfik F Ismail
- King's College London & Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Brandon Wong
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Kristi Sun
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Peter Gatehouse
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - David Firmin
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Stuart Cook
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
- National Heart Center, Singapore, Singapore
| | | | - Andrew Arai
- Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | | | - Dudley J Pennell
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Sanjay K Prasad
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
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Raphael CE, Liew AC, Mitchell F, Kanaganayagam GS, Di Pietro E, Newsome S, Owen R, Gregson J, Cooper R, Amin FR, Gatehouse P, Vassiliou V, Ernst S, O'Hanlon R, Frenneaux M, Pennell DJ, Prasad SK. Predictors and Mechanisms of Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy. Am J Cardiol 2020; 136:140-148. [PMID: 32950468 DOI: 10.1016/j.amjcard.2020.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/26/2020] [Accepted: 09/01/2020] [Indexed: 11/16/2022]
Abstract
Atrial fibrillation (AF) in hypertrophic cardiomyopathy (HC) is associated with significant symptomatic deterioration, heart failure, and thromboembolic disease. There is a need for better mechanistic insight and improved identification of at risk patients. We used cardiovascular magnetic resonance (CMR) to assess predictors of AF in HC, in particular the role of myocardial fibrosis. Consecutive patients with HC referred for CMR 2003 to 2013 were prospectively enrolled. CMR parameters including left ventricular volumes, presence and percentage of late gadolinium enhancement in the left ventricle (%LGE) and left atrial volume index (LAVi) were measured. Overall, 377 patients were recruited (age 62 ± 14 years, 73% men). Sixty-two patients (16%) developed new-onset AF during a median follow up of 4.5 (interquartile range 2.9 to 6.0) years. Multivariable analysis revealed %LGE (hazard ratio [HR] 1.3 per 10% (confidence interval: 1.0 to 1.5; p = 0.02), LAVi (HR 1.4 per 10 mL/m2[1.2 to 1.5; p < 0.001]), age at HC diagnosis, nonsustained ventricular tachycardia and diabetes to be independent predictors of AF. We constructed a simple risk prediction score for future AF based on the multivariable model with a Harrell's C-statistic of 0.73. In conclusion, the extent of ventricular fibrosis and LA volume independently predicted AF in patients with HC. This finding suggests a mechanistic relation between fibrosis and future AF in HC. CMR with quantification of fibrosis has incremental value over LV and LA measurements in risk stratification for AF. A risk prediction score may be used to identify patients at high risk of future AF who may benefit from more intensive rhythm monitoring and a lower threshold for oral anticoagulation.
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Affiliation(s)
- Claire E Raphael
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.
| | - Alphonsus C Liew
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Frances Mitchell
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | | | - Elisa Di Pietro
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Simon Newsome
- Department of Statistics, London School of Hygiene & Tropical Medicine, London, UK
| | - Ruth Owen
- Department of Statistics, London School of Hygiene & Tropical Medicine, London, UK
| | - John Gregson
- Department of Statistics, London School of Hygiene & Tropical Medicine, London, UK
| | - Robert Cooper
- Department of Cardiology, Liverpool Heart and Chest Hospital, Liverpool, UK
| | - Fouad R Amin
- Department of Cardiology, Frimley Park Hospital, Camberley, UK
| | - Peter Gatehouse
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | | | - Sabine Ernst
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Rory O'Hanlon
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | | | - Dudley J Pennell
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
| | - Sanjay K Prasad
- IHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
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Okafor J, Kanaganayagam GS, Patel K. A rare finding of giant accessory mitral valve tissue: a case report. Eur Heart J Case Rep 2020; 4:1-4. [PMID: 32128495 PMCID: PMC7047063 DOI: 10.1093/ehjcr/ytz244] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/27/2019] [Accepted: 12/06/2019] [Indexed: 11/25/2022]
Abstract
Background Accessory mitral valve tissue (AMVT) is a rare anomaly that can be detected in the first decade. It is associated with other congenital cardiac abnormalities, such as ventricular septal defect. When detected in adulthood, it is usually an incidental finding on echocardiography. Symptomatic individuals can present with breathlessness, syncope, and features of distal tissue embolization. Cardiac surgery is indicated in those with significant left ventricular outflow tract obstruction. Case summary A 45-year-old man without any significant medical history was referred due to an abnormal electrocardiogram. He was asymptomatic from a cardiac perspective. Echocardiography revealed the presence of a giant mobile mass attached to the anterior mitral valve leaflet and prolapsing into the left ventricular outflow tract (LVOT). This was classified as Type IIB2 AMVT. As there was no dynamic outflow tract obstruction on subsequent treadmill stress echocardiography, and in the absence of other coexistent congenital abnormality, surgical excision was not performed. Discussion It is important to exclude significant obstruction when a large AMVT is seen to be prolapsing into the LVOT. Three-dimensional echocardiography is the tool of choice for anatomical classification and to assess for concomitant congenital cardiac abnormalities.
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Affiliation(s)
- Joseph Okafor
- Cardiology Department, Chelsea and Westminister NHS Foundation Trust, 369 Fulham Rd, Chelsea, London SW10 9NH, UK.,Cardiology Department, Chelsea and Westminister NHS Foundation Trust, 369 Fulham Rd, Chelsea, London SW10 9NH, UK
| | - Gajen Sunthar Kanaganayagam
- Cardiology Department, Imperial College Healthcare NHS Trust, The Bays, South Wharf Road, St Mary's Hospital, London W2 1NY, UK
| | - Ketna Patel
- Cardiology Department, Chelsea and Westminister NHS Foundation Trust, 369 Fulham Rd, Chelsea, London SW10 9NH, UK
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MacLean E, Sehmi J, Kanaganayagam GS, Ngee T, Nicol E. P2243CTCA alone demonstrates superior diagnostic accuracy, prognostic utility and is less expensive than CTCA combined with subsequent multi-modality functional imaging in patients with ischaemic symptoms. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
The evaluation of suspected ischaemic symptoms incorporates multi-modality anatomical and functional imaging tests. The 2016 update to the UK's NICE guidelines recommends CT coronary angiogram (CTCA) first line in patients without known coronary artery disease. Additive multi-modality functional imaging may provide synergistic diagnostic and prognostic information.
Purpose
To investigate the diagnostic accuracy, prognostic utility and cost of CTCA combined with subsequent multi-modality functional testing versus (vs) CTCA alone.
Methods
772 consecutive patients were referred to a single UK tertiary centre with symptoms suggestive of ischaemia. 657 individuals (“CTCA group”) underwent CTCA alone, and 115 individuals (“Combined group”) underwent CTCA and then either perfusion cardiac MRI (n=25), stress echocardiogram (n=16), or myocardial perfusion scintigraphy (n=74). Patients underwent invasive angiography (n=79) +/− revascularisation at the discretion of the referring clinician. All readers and operators were aware of previous imaging findings. Revascularised patients (n=52) were excluded from long term follow-up. The remaining patients were followed-up for a mean of 38.1±17.4 months and the incidence of major adverse cardiovascular events (MACE) recorded. Costs were derived from the NICE guidelines.
Results
Baseline characteristics were similar between groups. The Combined group underwent significantly more invasive angiograms than the CTCA group (29.6% vs 6.8%, p=0.0001) with no significant difference in the rate of revascularisation (73% vs 67%, p=0.72). Mean time from CTCA to angiogram was significantly longer in the Combined group (81.2 vs 38.1 days, p=0.0001). Both sensitivity and specificity were lower in the Combined group than in the CTCA group (sensitivity: 70% vs 93%, specificity: 75% vs 100%). The rate of long term MACE was significantly higher in the Combined group (8.7% vs 2.6%, p=0.0026). Multivariate analysis of CTCA and functional imaging findings found that CTCA-derived four vessel aggregate stenosis score (0–12) was the strongest predictor of MACE for the whole cohort (OR 4.4, p<0.0001), and also for those with negative functional tests (OR 3.9, p<0.0001). Per patient, a combined strategy was more expensive than CTCA alone (£1551 vs £368, p=0.0001).
CTCA and functional data vs outcomes
Conclusions
Combining multi-modality functional testing with CTCA increased costs but did not improve diagnostic accuracy or long term outcomes. Further reductions in both MACE and unnecessary invasive angiography are desirable; CT-derived functional data such as FFRCT may be implicated.
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Affiliation(s)
- E MacLean
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - J Sehmi
- Royal Brompton Hospital, Cardiovascular Imaging, London, United Kingdom
| | - G S Kanaganayagam
- Royal Brompton Hospital, Cardiovascular Imaging, London, United Kingdom
| | - T Ngee
- Royal Brompton Hospital, Cardiovascular Imaging, London, United Kingdom
| | - E Nicol
- Royal Brompton Hospital, Cardiovascular Imaging, London, United Kingdom
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Kanaganayagam GS, Ngo AT, Alsafi A, Kamanahalli R, Sutaria N, Mittal T, Ariff B. CT coronary angiography in the investigation of chest pain — Beyond coronary artery atherosclerosis; A pictorial review. Int J Cardiol 2014; 176:618-29. [DOI: 10.1016/j.ijcard.2014.08.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 07/13/2014] [Accepted: 08/05/2014] [Indexed: 12/26/2022]
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Kanaganayagam GS, Moscarelli M, Punjabi PP, Fox KF. Feeling dizzy? A giant incidental finding. Eur Heart J 2014; 35:2343. [PMID: 24944327 DOI: 10.1093/eurheartj/ehu237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Marco Moscarelli
- Department of Cardiovascular surgery, Imperial College London, London, UK
| | - Prakash P Punjabi
- Department of Cardiovascular surgery, Imperial College London, London, UK
| | - Kevin F Fox
- Department of Cardiology, Imperial College London, London, UK
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Kanaganayagam GS, Malik IS. Modern management of a patent foramen ovale. JRSM Cardiovasc Dis 2012; 1:10.1258_cvd.2012.012017. [PMID: 24175077 PMCID: PMC3738369 DOI: 10.1258/cvd.2012.012017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A patent foramen ovale (PFO) has been associated with medical conditions such as cryptogenic stroke, migraine with aura, and decompression illness. Whether closure of the PFO has clinical benefit has been suggested from registry studies, but not yet confirmed in multiple randomized trials. Methods of diagnosis of a PFO and a summary of the current evidence for treatment is presented and discussed as a guide to patient-centred decision-making.
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Affiliation(s)
- G S Kanaganayagam
- Hammersmith Hospital, Cardiovascular Sciences and the Renal Institute, Imperial College London and Imperial College Healthcare NHS Trust , London , UK
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Clements-Jewery H, Kanaganayagam GS, Kabra R, Curtis MJ. Actions of flecainide on susceptibility to phase-2 ventricular arrhythmias during infarct evolution in rat isolated perfused hearts. Br J Pharmacol 2006; 147:468-75. [PMID: 16415912 PMCID: PMC1616984 DOI: 10.1038/sj.bjp.0706633] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The mechanism of flecainide-induced unexpected death remains uncertain. Phase-2 ventricular arrhythmias occur during infarct evolution. We examined whether flecainide (0.74 and 1.48 microM, representing the peak unbound plasma and total blood concentrations, respectively, at 'therapeutic' dosage) has proarrhythmic activity on phase-2 arrhythmia susceptibility during infarct evolution. To achieve this, we used the Langendorff-perfused rat heart preparation (n=8 per group) in which baseline phase-2 arrhythmia susceptibility is low. Left main coronary occlusion evoked phase-1 (acute ischaemia-induced) ventricular arrhythmias including fibrillation (VF) in all hearts. By 90 min, hearts were relatively arrhythmia-free. Randomized and blinded switch of perfusion to flecainide at 90 min caused no increase over baseline in the incidence of VF, tachycardia (VT) or premature beats (VPB) during the following 150 min of ischaemia, or during reperfusion (begun 240 min after the onset of ischaemia). In separate hearts, catecholamines (313 nM norepinephrine and 75 nM epinephrine) were co-perfused with flecainide from 90 min of ischaemia. Catecholamine perfusion increased heart rate, coronary flow and QT interval, and shortened PR interval (all P<0.05), actions that were not altered by flecainide. Catecholamine perfusion caused a weak nonsignificant increase in phase-2 VPB, VT and VF incidence, but there was no proarrhythmic interaction with flecainide. In conclusion, the present findings suggest that the increased risk of death associated with clinical use of flecainide is not due to facilitation of phase-2 ventricular arrhythmias.
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Affiliation(s)
- Hugh Clements-Jewery
- Cardiovascular Division, Kings College London, The Rayne Institute, St Thomas' Hospital, London, SE1 7EH
| | | | - Ruchi Kabra
- Cardiovascular Division, Kings College London, The Rayne Institute, St Thomas' Hospital, London, SE1 7EH
| | - Michael J Curtis
- Cardiovascular Division, Kings College London, The Rayne Institute, St Thomas' Hospital, London, SE1 7EH
- Author for correspondence:
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