The challenge of asymptomatic coronary artery disease in aircrew; detecting plaque before the accident

Navigating Coronary Artery Disease in Aviation Cardiology in Australia and New Zealand

BACKGROUND

Cardiologists will commonly assess patients who hold an aviation medical certificate and require unique assessments and communications with national civil aviation authorities (in Australia, the Civil Aviation Safety Authority [CASA] and in New Zealand, the Civil Aviation Authority of New Zealand [CAA NZ]). Cardiac conditions are the most common reason for disqualification from holding an aviation licence, and coronary artery disease is considered a high-risk condition for pilot incapacitation.

AIM

To provide a contemporary update on the aeromedical approach to the evaluation, detection, and management of coronary artery disease in an Australasian context.

METHODS

A narrative view of current and historical practice in the area of aeromedical evaluation of coronary disease was undertaken.

RESULTS

This review highlights the aeromedical approach to risk stratification and specific challenges of the aviation environment for patients with coronary artery disease. Scenarios of coronary artery disease screening, common and rare acute coronary syndromes, and the assessment of established coronary artery disease are examined in detail. Suggestions to facilitate communications between specialists and CASA or CAA NZ to facilitate patient re-certification are also provided.

CONCLUSION

Patients who are pilots have unique requirements in terms of their coronary assessment, management, and follow-up to maintain eligibility to fly. It is important for cardiologists to be aware of relevant occupational requirements to provide optimal care to their patients.

Screening for Coronary Artery Disease in Asymptomatic Pilots with Diabetes Mellitus

INTRODUCTION: Coronary artery disease (CAD) is a cause of death in 75% of patients with diabetes. Its often asymptomatic nature delays diagnosis. In aeronautics, it can cause in-flight incapacitation, beyond which it represents a major fear for the medical expert. Screening for CAD is still a topical subject with the advent of new cardiovascular (CV) risk biomarkers and more effective screening tests. We report the experience of the Aeromedical Expertise Center of Rabat in this screening of diabetic pilots, with a recommendations review.METHODS: A prospective study over 1 yr included diabetic pilots who benefited from systematic screening for CAD after a CV risk stratification. Coronary angiography is performed if a screening test is positive. Subsequent follow-up is carried out in consultation with the attending physician with regular evaluation in our center.RESULTS: There were 38 pilots included in our study. The average age was 55 ± 4.19 yr and about 73% had a high CV risk. CAD was detected in 4 cases (10.52%) who had abnormal resting electrocardiograms and required revascularization with the placement of active stents. Approximately 75% of pilots with CAD returned to fly through a waiver with restrictions.DISCUSSION: Screening for coronary disease in diabetics is controversial, and current recommendations are not unanimous. In our study, the screening did not identify coronary diabetic pilots who could benefit from bypass surgery. Nevertheless, coronary disease was diagnosed, justifying grounding to preserve flight safety, which is an absolute priority in aviation medicine.Zerrik M, Moumen A, El Ghazi M, Smiress FB, Iloughmane Z, El M'hadi C, Chemsi M. Screening for coronary artery disease in asymptomatic pilot with diabetes mellitus. Aerosp Med Hum Perform. 2024; 95(4):200-205.

Review of the National Institute for Health and Care Excellence guidelines on the management of atrial and ventricular arrhythmias

The National Institute for Health and Care Excellence (NICE) guidelines present a synopsis of extensive internal evidence and technology reviews, with a particular focus on clinical efficacy and cost-effectiveness within the NHS in England. This approach has delivered a novel perspective on arrhythmia management, with important distinctions from other policymakers' recommendations. For example, when compared with the European Society of Cardiology (ESC) and the American Heart Association (AHA)/Heart Rhythm Society (HRS)/American College of Cardiology (ACC) guidelines on atrial fibrillation (AF), NICE advocates unique strategies regarding arrhythmia detection, stroke and bleeding risk stratification, and rhythm control (NICE CG 196). Likewise, for patients at risk of sudden cardiac death, NICE TA314 not only recommends device therapy based on New York Heart Association class and ECG findings, but also incorporates quality-adjusted life year data from analysis of key randomised controlled trials.This review examines the NICE guidelines, together with those from the AHA/HRS/ACC and ESC, on the management of AF and ventricular arrhythmias and highlights the key common features and discrepancies between these important documents.

Exercise ECG for Screening in Military Aircrew

INTRODUCTION: The exercise electrocardiogram (ExECG), or stress test, is a widely used screening tool in occupational medicine designed to detect occult coronary artery disease, and assess performance capacity and cardiovascular fitness. In some guidelines, it is recommended for high-risk occupations in which occult disease could possibly endanger public safety. In aviation medicine, however, there is an ongoing debate on the use and periodicity of ExECG for screening of aircrew.METHOD: In the German Armed Forces, aircrew applicants and active-duty aircrew undergo screening ExECG. We analyzed 7646 applicant ExECGs (5871 from pilot and 1775 from nonpilot applicants) and 17,131 ExECGs from 3817 active-duty pilots. All were performed at the German Air Force Centre of Aerospace Medicine (GAFCAM) and analyzed for ECG abnormalities, performance capacity, blood pressure, and heart rate response.RESULTS: Only 15/5871 (0.2%) of pilot applicants required further investigation and none were ultimately disqualified for aircrew duties due to their ExECG results. Of the nonpilot applicants, 22/1775 (1.2%) required further diagnostic work-up due to their ExECG findings, with only 1 ultimately disqualified. From active-duty pilots, 84/17,131 (0.5%) ExECGs revealed findings requiring further investigation, with only 2 pilots ultimately disqualified from flying duties.DISCUSSION: The extremely low yield of ExECG findings requiring further evaluation and/or disqualification for aircrew duties suggest its use is questionable and not cost-effective as a screening tool in this cohort. It may be enough to perform ExECG on clinical indication alone.Guettler N, Nicol ED, Sammito S. Exercise ECG for screening in military aircrew. Aerosp Med Hum Perform. 2022; 93(9):666–672.

Grounding of Pilots: Medical Reasons and Recommendations for Prevention

BACKGROUND: This article presents the results of an EASA-commissioned study aimed at analyzing the medical causes of grounding of a broad European pilot population and recommending measures to reduce the risk of in-flight incapacitation in commercial air transport pilots.METHOD: European National Aviation Authorities (NAAs) were requested to provide data concerning the total number of pilots that were examined, their age and license category, number of unfit pilots, and the medical causes of each case of grounding. Diagnoses were classified according to the format and definitions laid down in Commission Regulation (EU) No. 1178/2011 Part Med.RESULTS: Analyzed were 82,435 cases assessed by 6 NAAs. Of these cases, 2.1% were assessed as unfit to fly. Frequent causes for grounding a pilot were cardiovascular (19%), psychiatric (11%), neurological (10%), and psychological (9%). Cardiovascular conditions were the most frequent cause for grounding in the older age groups, with 21% in the age 51-60 cohort, 28% in the age 61-65 cohort, and 48% in those beyond 65 yr. Psychiatric and psychological diagnoses were most frequent in the age 20-40 cohort.DISCUSSION: Cardiovascular conditions were the most frequent cause for grounding. Cardiovascular diseases (CVD) are associated with modifiable risk factors. Tackling these risk factors gives aeromedical examiners the opportunity to improve the health of pilots and reduce CVD-related flight safety risks by reducing the number of pilots at risk of in-flight incapacitation. The mandatory periodical medical examination of pilots provides an excellent framework for risk prevention and follow-up of preventive measures.Simons R, Maire R, Van Drongelen A, Valk P. Grounding of pilots: medical reasons and recommendations for prevention. Aerosp Med Hum Perform. 2021; 92(12):950-955.

CT coronary angiography-guided cardiovascular risk screening in asymptomatic patients: is it time?

Cardiovascular disease (CVD) is the leading cause of death in the UK, whilst millions live with various forms of the disease. Coronary artery disease constitutes a significant portion of this morbidity and mortality, and is the leading cause of premature death. Increasing focus is thus being placed on the optimisation of CVD prevention, where risk screening plays a key role. Indeed, the decline in age-adjusted cardiovascular mortality achieved up to now has been largely attributed to primary preventative therapies (e.g., statins) introduced earlier in the disease process. National initiatives exist to improve cardiovascular health at a population level, but in its current form, CVD screening at the individual level is predominantly undertaken using multivariate risk scores based on population-based data. These have multiple innate flaws, highlighted in this review. Non-invasive imaging plays a key role in the screening of other disease processes, helping to personalise the screening process. Although the coronary artery calcium score as a screening tool has a role in national and international guidance, whether a shift to screening with computed tomography coronary angiography (CTCA) is now appropriate is open for discussion. Image acquisition techniques continue to improve with reducing radiation exposure and an ever-expanding evidence-base for additional prognostic data offered by CTCA. This enables the potential identification of sub-clinical atherosclerosis, including with novel artificial intelligence techniques. This review aims to report current guidelines regarding cardiac CT imaging in the asymptomatic primary prevention setting, advances in various CT technologies and future opportunities for progress in this field.

SIRM-SIC appropriateness criteria for the use of Cardiac Computed Tomography. Part 1: Congenital heart diseases, primary prevention, risk assessment before surgery, suspected CAD in symptomatic patients, plaque and epicardial adipose tissue characterization, and functional assessment of stenosis

In the past 20 years, Cardiac Computed Tomography (CCT) has become a pivotal technique for the noninvasive diagnostic work-up of coronary and cardiac diseases. Continuous technical and methodological improvements, combined with fast growing scientific evidence, have progressively expanded the clinical role of CCT. Recent large multicenter randomized clinical trials documented the high prognostic value of CCT and its capability to increase the cost-effectiveness of the management of patients with suspected CAD. In the meantime, CCT, initially perceived as a simple non-invasive technique for studying coronary anatomy, has transformed into a multiparametric "one-stop-shop" approach able to investigate the heart in a comprehensive way, including functional, structural and pathophysiological biomarkers. In this complex and revolutionary scenario, it is urgently needed to provide an updated guide for the appropriate use of CCT in different clinical settings. This manuscript, endorsed by the Italian Society of Medical and Interventional Radiology (SIRM) and by the Italian Society of Cardiology (SIC), represents the first of two consensus documents collecting the expert opinion of Radiologists and Cardiologists about current appropriate use of CCT.

Coronary Artery Disease Evaluation and Management Considerations for High Risk Occupations: Commercial Vehicle Drivers and Pilots

Optimal treatment of stable ischemic heart disease for those in the transportation industry is considered in the context of the individual's health, as well as with the perspective that sudden impairment could have catastrophic consequences for others. This article focuses on two high risk occupations that one may encounter in practice: commercial motor vehicle drivers and commercial pilots. This article discusses coronary heart disease in patients in high risk occupations and covers current guideline recommendations for screening, treatment, and secondary prevention. The importance of the complimentary perspectives of the regulatory agency, medical examiners, physicians, and pilot or driver are considered in this narrative review, as are considerations for future guideline updates.

Challenges in Utilizing CT Coronary Angiography and CT Calcium Scoring to Determine Aeromedical Fitness for Aicrew: A Tale of 3 CTs

The management of coronary artery disease (CAD) in aviators remains as one of the dominant preoccupation in determining vocational fitness. With the emerging awareness and accessibility of non-invasive modalities for assessing CAD, there is an increasing likelihood that aircrew may have undergone some form of functional or anatomic assessment of the coronary circulation, prior to their presentation to the aviation medical examination office. In particular, computer tomographic coronary angiography (CTCA) and CT coronary artery calcium scoring (CACS) had gained significant traction in recent years, as novel scanning algorithms had enabled faster, safer and more affordable imaging. However, the utilization of CTCA and CACS are not without challenges. Against this backdrop, this paper presents three clinical vignettes of aviators who presented to our cardiac department for specialist evaluation and the eventual aeromedical dispositions. The paper also discusses the evolving opportunities and issues in the application of CTCA and CACS findings to aeromedical risk assessment in aviators.

Return to flying after coronary artery disease: A case series among Malaysian pilots

OBJECTIVES

Pilots with coronary artery disease (CAD) are at increased risk of myocardial infarction, stroke, and possibly death. Return to flying duties may be considered after a detailed risk assessment. The aim of this retrospective case series is to describe the return to flying duty process.

METHODS

We conducted a retrospective case review of pilots diagnosed with CAD at the Institute of Aviation Medicine (IAM), Royal Malaysian Air Force (RMAF) in October 2020.

RESULTS

Thirteen cases of CAD were included in the review. Ten pilots were diagnosed after developing acute coronary syndrome; the remaining three pilots were diagnosed during a routine medical examination via an exercise stress test. Twelve pilots required a revascularization procedure. A total of 11 pilots (84.6%) were recertified for flying duties, while another two were disqualified. The duration to recertification for these 11 pilots was between three months and one year.

CONCLUSIONS

The risk assessment was initiated with initial risk-stratification using population-appropriate risk calculator combined with the 4 × 4 aeromedical risk matrix. The reassessment of return to flying after coronary artery disease must be carried out no sooner than six months after the event. Pilots must be hemodynamically stable with no evidence of significant inducible ischemic left and a minimum 50% of ventricular ejection fraction (LVEF). A follow-up is recommended at the initial six months after recertification and then annually with a routine noninvasive cardiac assessment.

Coronary Artery Disease Screening Using CT Coronary Angiography

BACKGROUND: The increased utility of CT coronary angiography (CTCA) in cardiovascular screenings of aircrew has led to the increased detection of asymptomatic coronary artery disease (CAD). A systematic review of studies relevant to the interpretation of CTCA for the occupational fitness assessment of high-risk vocations was performed, with findings used to describe the development of a pathway for the aeromedical disposition of military aviators with asymptomatic CAD.METHODS: Medline was searched using the terms CT coronary angiogram and screening and prognosis. The inclusion criteria were restricted to study populations ages > 18 yr, were asymptomatic, were not known to have CAD, had undergone CTCA, and with their associations with major adverse cardiovascular events (MACE) and other relevant cardiac outcomes reported.RESULTS: Included in this systematic review were 10 studies. When compared to subjects with no or nonobstructive CAD, those with obstructive CAD on CTCA had hazard ratios (HR) for cardiac events ranging from 1.42 to 105.48. Comparing subjects with nonobstructive CAD and those without CAD on CTCA, a lower HR of 1.19 for cardiac events was found. The annual event rates of subjects with no CAD on CTCA were extremely low, ranging from 0 to 0.5%.CONCLUSIONS: Based on the findings, we suggest that CTCA should only be performed in aircrew with higher cardiac risk profiles. Those found to have no CAD or minimal CAD (i.e., 25% stenosis) in a non-left main coronary artery on CTCA can be returned to flying duties. All other results should be further evaluated with an invasive angiogram.Cheong RWL, See B, Tan BBC, Koh CH. Coronary artery disease screening using CT coronary angiography. Aerosp Med Hum Perform. 2020; 91(10):812817.

An introduction to aviation cardiology

The management of cardiovascular disease (CVD) has evolved significantly in the last 20 years; however, the last major publication to address a consensus on the management of CVD in aircrew was published in 1999, following the second European Society of Cardiology conference of aviation cardiology experts. This article outlines an introduction to aviation cardiology and focuses on the broad aviation medicine considerations that are required to manage aircrew appropriately and optimally (both pilots and non-pilot aviation professionals). This and the other articles in this series are born out of a 3 year collaborative working group between international military aviation cardiologists and aviation medicine specialists, many of whom also work with and advise civil aviation authorities, as part of a North Atlantic Treaty Organization (NATO) led initiative to address the occupational ramifications of CVD in aircrew (HFM-251). This article describes the types of aircrew employed in the civil and military aviation profession in the 21st century; the types of aircraft and aviation environment that must be understood when managing aircrew with CVD; the regulatory bodies involved in aircrew licensing and the risk assessment processes that are used in aviation medicine to determine the suitability of aircrew to fly with medical (and specifically cardiovascular) disease; and the ethical, occupational and clinical tensions that exist when managing patients with CVD who are also professional aircrew.