login
Password reminder
Cardiovascular News
Contact the editor Visit Cardiovascular News Twitter feed Visit Cardiovascular News Facebook page
 

Is magnetic resonance imaging a useful tool to identify the cause of malignant ventricular arrhythmias?


Tuesday, 27 Mar 2012 12:30
James White
James White


By James White


Approximately 5–6% of deaths occurring annually in North America are classified as sudden cardiac death, a designation indicating its occurrence within one hour of symptom onset. Patients with resuscitated sudden cardiac death or sustained (>30 seconds) ventricular tachycardia represent a particularly high-risk population for future sudden cardiac death and typically undergo a battery of testing in an attempt to identify a clear precipitant of the event. This is typically inclusive of echocardiography, invasive angiography and the selective use of other more specialised imaging tests. However, the diagnostic yield of cardiac imaging in this clinical setting has not been evaluated.


Cardiovascular magnetic resonance (CMR) imaging has evolved to provide comprehensive evaluations of cardiac morphology, function and tissue health. The latter, inclusive of T2-weighted “oedema” imaging, T1-weighted “fat” imaging, and delayed enhancement “scar” imaging provides a potentially robust platform for the evaluation of arrhythmia substrate. In our recent publication (White J A,
et al Circulation: Cardiovascular Imaging [2012] 5:12–20) we evaluated the diagnostic yield of CMR imaging versus all other clinically ordered imaging tests among a consecutive series of 82 patients presenting with resuscitated sudden cardiac death or ventricular tachycardia.


Patients with clinical evidence of ischaemia were excluded. The study identified that the detection of any relevant cardiac abnormality by non-CMR imaging was modest at 49% patients. Conversely, CMR identified relevant disease in 74% of patients, offering incremental detection of acute myocardial injury (i.e. associated with oedema) in 17% as well as the detection of unrecognised chronic myocardial disease. In those having resuscitated sudden cardiac death up to one-third of patients had evidence of acute tissue injury.


The tissue pathologies uniquely identified by CMR in this population were subendocardial-based ischaemic injury and subepicardial-based inflammatory injury; each identified both with and without associated oedema, a measure of disease acuity.


CMR was effective at identifying patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) but also identified patients with other chronic injury patterns within the right ventricle attributable to inflammatory myocarditis.


This represents the first evaluation of diagnostic utility for cardiac imaging in patients presenting with ventricular arrhythmias. While recognising that contemporary advancements in non-CMR imaging, such as echocardiography-based strain imaging, were not evaluated, the study does identify that routine clinical non-CMR imaging may neglect relevant cardiac pathology in this cohort and accrues a relatively modest diagnostic yield. The use of CMR imaging achieved a more robust diagnostic yield and did so through its unique identification of tissue level pathology. Most importantly, acute tissue injury was identified in a significant number of patients.


The clinical relevance of re-classifying patients with respect to the presence of acute tissue injury by CMR is yet uncertain and requires ongoing study. By convention, clinically recognised acute ischaemic injury is considered sufficient justification of a transient arrhythmia precipitant to negate need for secondary prevention implantable cardiac defibrillator therapy. However, whether or not sub-clinical CMR evidence of the same should carry a similar recommendation is an interesting and debatable question. Accordingly, there is a need for prospective clinical trials and registries in this field to assist in answering these important clinical questions.


James White is a cardiologist, C
ardiovascular MRI Clinical Research Program, MRI Unit, Robarts Research Institute, London, Canada.

 




Add New Comment

Most popular


Men believe “long working hours” stop women from being interventional cardiologists
Wednesday, 15 Jul 2015
According to a new survey published in EuroIntervention, men state that the long working hours and the need to be on call that is associated with being an interventional cardiologist are the key ... Men believe “long working hours” stop women from being interventional cardiologists

Boston Scientific launches bioresorbable scaffold trial
Monday, 20 Jul 2015
Boston Scientific has initiated a study to evaluate its fully resorbable scaffold technology. FAST (Fully absorbable scaffold feasibility study) is a prospective, single-arm study designed to assess ... Boston Scientific launches bioresorbable scaffold trial

Abbott Vascular expands its  structural heart portfolio with new mitral valve technologies
Friday, 31 Jul 2015
Abbott Vascular has announced it has entered into an agreement to purchase Tendyne Holdings (focused on developing minimally invasive mitral valve replacement therapies) and secured an option to ... Abbott Vascular expands its  structural heart portfolio with new mitral valve technologies

Features


Bifurcation lesions: When a two-stent technique is needed
Tuesday, 18 Aug 2015
The advent of second-generation drug-eluting stents and the associated improved safety and efficacy has meant that the risks of using two stents for bifurcation lesions has significantly decreased. M... Bifurcation lesions: When a two-stent technique is needed

Getting to grips with social media
Tuesday, 04 Aug 2015
Pascal Meier believes that social media is the logical next step from the internet—just as the internet has revolutionised connectivity, social media is revolutionising communication. In this ... Getting to grips with social media

Profiles


Deepak L Bhatt
Tuesday, 09 Jun 2015
Deepak L Bhatt (Executive director of Interventional Cardiovascular Programs, Brigham and Women’s H... Deepak L Bhatt

Flavio Ribichini
Thursday, 05 Mar 2015
Flavio Ribichini speaks to Cardiovascular News about being involved in the first use of primary ... Flavio Ribichini

Cardiac Rhythm News Vascular News Cardiovascular News Interventional News Spinal News NeuroNews
BIBA Medical BIBA MedTech Insights CX Symposium ilegx
Password Reminder

BIBA Medical, 526 Fulham Road, Fulham, London, SW6 5NR.
TEL: +44 (0)20 7736 8788 FAX: +44 (0)20 7736 8283 EMAIL: 
info@bibamedical.com
© BIBA Medical Ltd is a company registered in England and Wales with company number 2944429.
VAT registration number 730 6811 50.
Site Map | Terms and Conditions