This distinct bilateral diagonal ear lobe crease (Figures 1 and2) was noticed in an 85-year-old gentleman who presented to the ambulance service with chest tightness and shortness of breath at rest. He told the ambulance crew that he had previously had problems with his breathing and his heart. He received pre-hospital treatment from the paramedic crew with 300 mg oral aspirin, 400 mcg sublingual glyceryl trinitrate and 5 mg of intravenous morphine sulphate. After serial 12-lead electrocardiograms and repeat serum troponin levels, he was diagnosed with a non-ST-elevation myocardial infarction (NSTEMI); the cause for his chest tightness and shortness of breath. He received medical management of his NSTEMI on the High Dependency Unit, and was discharged home a month later.
In the out-of-hospital environment, the availability of a comprehensive past medical history may be limited and the range of investigations available to the healthcare provider is restricted. As a result, pre-hospital care providers must ensure that their history taking and physical examination skills are highly developed. In this case, the patient presented with a history suggestive of either respiratory or cardiovascular pathology. In cases where there is a lack of detailed medical history, and biochemical testing is not readily available, any further information to aid a diagnosis, risk stratification and subsequent management plan is vital to the clinician.
Frank's Sign
A diagonal earlobe crease (DELC) or Frank's Sign, has been linked with ischaemic heart disease since it was first described in 1973 by Dr. Sanders Frank (Frank, 1973). A classification system has since been developed, outlining the severity of DELC where observed, although its inter-observer reliability has not been demonstrated. However, the degree of association of this peculiar anatomical variant with coronary artery disease (CAD) remains controversial. As a result, DELC is often not discussed alongside other systemic features one should search for during the physical examination of the cardiovascular system. Despite this controversy, a CT-based study of 430 patients published in 2012 found DELC to be a significant predictor of CAD with a sensitivity of 78% and specificity of 43% (Shmilovich et al, 2012). This is in keeping with other researchers' findings that there is an important correlation between dermatological features of ageing, especially parietal baldness and DELC, and a diagnosis of CAD (Fabijanić et al, 2012). Furthermore, a recent coronary angiography study from China found a statistically significant link between DELC and having >50% stenosis of at least one major coronary vessel, in their population of 558 consecutive patients with known or suspected CAD (Wang et al, 2016). This study highlighted that in this specific population, male participants with DELC were 441% more likely to suffer from coronary heart disease than male participants without DELC, with the same comparison showing a 536.8% increased likelihood in female study participants (Wang et al, 2016). While the above studies highlight that DELC is not highly sensitive for coronary artery disease, and can lack specificity, these figures should reassure the pre-hospital clinician that there certainly exists a correlation between DELC and ischaemic heart disease.
A 35-year-long prospective cohort study published in 2014 (Christoffersen et al, 2014) studied 10885 patients, 5109 of whom developed CAD, and confirmed that DELC is associated with CAD, independent of age and other known risk factors, producing significantly increased hazard ratios for myocardial infarction and ischaemic heart disease. The same study found that looking ‘old for your age’ is a marker of poor cardiovascular health, and that in this regard DELC acts as an objective visible marker of old age, in addition to corneal arcus, grey hair, xanthelasmata and facial wrinkles (Christoffersen et al, 2014). As risk of CAD is well known to increase with age, a finding of DELC would be of more significance in a younger patient. The literature suggests that below the age of 60 years DELC is a useful diagnostic finding (Xu et al, 2014). This is hypothesised to be because it is a surrogate marker of premature biologic ageing, most probably due to increased free radical oxidative stress in these individuals contributing to CAD (Klings et al, 2001; Fabijanić et al, 2012; Vichova et al, 2013). Its usefulness as a predictive marker in patients with type two diabetes mellitus should however be questioned. This was demonstrated by a study of 1,022 patients with diabetes which found that after adjusting for known cardiovascular risk factors, ethnicity and socioeconomic class, DELC was not demonstrated to be a statistically significant independent predictor of CAD, with a p-value of p=0.45 (Davis et al, 2009).
Conclusion
Frank's Sign is seldom discussed or used as a diagnostic aid in prehospital care yet the literature would suggest that in conjunction with other markers of ischaemic heart disease and atherosclerosis, Frank's Sign should be seen as an adjunct to diagnosing suspected coronary artery disease (Dwivedi et al, 2010) and its presence may identify patients at increased risk of CAD (Agouridis et al, 2015). Its presence in a patient under the age of 60 with no history of CAD should rouse suspicion, and aid clinical decision making in relation to the choice of future investigations and management. However, it should not be seen a pathognomonic finding and as such, should be considered alongside the findings of a full physical examination and relevant investigations.