Biomedical subjects

Ross MacKenzie

Publications and source records attributed to Ross MacKenzie.

9 recordsLinked to original sources

PubMed2006

Positive computer-generated exercise electrocardiogram.

The use of computerized averaging of the electrocardiogram (ECG) during stress testing has facilitated the removal of motion artifacts and baseline shifts. However, this process can introduce errors, which may not be appreciated by medical directors. Such errors can lead to significant ST depression in the absence of coronary artery disease. Such false-positive tests may lead to anxiety in the applicant, delays in accepting the application and unnecessary additional testing. This case study illustrates a common pitfall associated with using only a computer-generated exercise ECG for risk assessment of a life insurance applicant.

Actuarial Analysis↗

PubMed2005

Poor R-wave progression.

Poor R-wave progression is a common ECG pattern, which is often inconclusively interpreted by medical directors. Although this ECG pattern is commonly attributed to anterior myocardial infarction, it may also be caused by left bundle branch block, Wolff-Parkinson-White syndrome, right and left ventricular hypertrophy as well as by faulty ECG recording technique. Failure to make a definitive interpretation of this pattern may result in a delay or loss of business.

Adult↗

PubMed2005

Short PR interval.

A short PR interval may be associated with an otherwise normal electrocardiogram or a myriad of bizarre electrocardiographic abnormalities. Clinically, the individual may be asymptomatic or experience a variety of complex arrhythmias, which may be disabling and rarely cause sudden death. In life insurance applicants, it is important to recognize these abnormalities and to assess their risk appropriately.

Adult↗

PubMed2005

Left axis deviation.

Left axis deviation is one of the most commonly encountered ECG abnormalities. Its presence should alert medical directors and underwriters to the possibility of underlying structural heart disease. Many of the causes of left axis deviation are apparent from the clinical findings. Left anterior fascicular block is one of the commonest causes of left axis deviation and has specific ECG criteria for its diagnosis.

Adult↗

PubMed2005

Right atrial abnormality.

Occasionally, a prominent P wave is encountered in a life insurance applicant's electrocardiogram. Prominent P waves may be normal variants or alert the medical director to prognostically significant structural heart or pulmonary disease. This case study reviews the commonly used criteria for the ECG pattern of right atrial abnormality and some of the pitfalls associated with its use.

Adult↗

PubMed2004

Asymptomatic ST segment elevation.

Asymptomatic ST segment elevation in a life insurance applicant's ECG raises several prognostically important possibilities such as myocardial infarction, pericarditis, Brugada syndrome and early repolarization. This ECG case study discusses the ECG features involved in the differential diagnosis.

Adult↗

PubMed2004

Giant negative T waves.

Marked T wave inversion in a life insurance applicant's ECG may suggest high risk. Careful analysis of the ECG, an informative attending physician statement, and judicious use of additional testing allows the medical director to put this striking ECG abnormality in its proper context.

Actuarial Analysis↗

PubMed2004

Tall R wave in lead V1.

Tall R waves in lead V1 present the life insurance company medical director with a diagnostic dilemma. This ECG pattern may be present in applicants with right bundle branch block, right ventricular hypertrophy, Wolff-Parkinson-White syndrome, posterior myocardial infarction, hypertrophic cardiomyopathy, muscular dystrophy, dextrocardia, misplaced precordial leads, as well as in normal individuals. This ECG case study discusses the ECG features involved in the differential diagnosis.

Diagnosis, Differential↗

PubMed2004

Second-degree AV block.

Second-degree AV block includes a variety of conduction patterns of variable prognostic significance. Careful analysis of the pattern of PR and R-R intervals, the QRS axis and duration, as well as the presence or absence of structural heart disease should allow the medical director to assess the applicant's risk for life insurance.

Electrocardiography↗