25 The use of cardiovascular magnetic resonance (CMR) imaging in the assessment of personnel in the UK armed forces

Introduction

The Armed Forces places considerable occupational demands on its workforce. Cardiovascular disease (CVD) remains a common cause of death and premature discharge. Simple CVD screening is performed periodically throughout the careers of service personnel, particularly in those in high risk roles such as aircrew. Abnormalities commonly require investigation with advanced cardiovascular imaging.

Methods

A retrospective cohort analysis of all military CMR requests to two military cardiologists was undertaken to determine demographics, reason for referral, results of investigation and occupational outcome.

Results

Between 2011 and 2015, fifty-six patients (95% male, median age 44 years) were referred for CMR. The commonest indications were abnormal echocardiography (21%), ventricular ectopy (16%), suspicion of cardiomyopathy (13%) and other asymptomatic ECG abnormalities (T wave inversion (11%) and bundle branch block (7%)). Of the CMR scans performed, 25% demonstrated features confirming cardiomyopathy (25% dilated and 12.5% hypertrophic phenotype). CMR features of athletic heart were seen in 11% of scans, and considered potentially suggestive of early cardiomyopathy. A quarter of patients had significant late gadolinium enhancement, in a variety of pathological patterns. Adenosine stress imaging was performed in 21% of patients, a quarter of which demonstrated perfusion abnormalities. Whilst 30% of patients were able to return to unrestricted duties following CMR, 70% required occupational restriction, mostly in aircrew. Of these 18% were unable to fly pending further review, 36% were deemed unfit to fly solo, and 7% had restrictions placed on their ability to deploy on overseas operations.

Conclusion

CMR is a valuable tool in the investigation of military personnel, and a useful adjunct to determine occupational, as well as clinical, risk. With the recent introduction of more rigorous CVD screening to join the Army, and the importance of comprehensive risk assessment in aircrew, the use of CMR in this population is likely to increase.