Running with Heart
by Dr. Anne G Evans, MBA
Although regular aerobic exercise, including running, is consistent with excellent
cardiovascular health there are cardiac disorders that may afflict runners. As with Bob
Lafferty (see below) cardiac disorders are not always readily detected and can be masked by
existing non-cardiac disease. My father, another example, was fit, ate healthfully and
exercised daily. At 52, he returned from his usual morning run-and died of a heart
What cardiac disorders can runners experience? What are their warning signs? What precautionary
measures should be taken by even the fittest? This article provides an introduction to some of
the cardiac disorders that can threaten the fitness runner.
Cardiac Disorders Every Runner Should Know About
Understanding cardiac disorders relevant to runners requires learning some medical jargon. Some
of the basic terms are explained below.(1)
Arrhythmia - an irregular heart beat
The heart muscle's chambers (two atrial and two ventricular) normally beat in a coordinated
sequence driven by inherent electrical activation. The beat represents the chambers' orderly
contraction and relaxation, which pumps blood through the body. Electrical activation
originates from the sinoatrial node within the heart wall, spreads through the atria initiating
atrial contraction, then through the ventricles causing ventricular contraction. During
relaxation the heart refills with blood in preparation for the next beat. Any distortion of
this regular (sinus) rhythm is an arrhythmia. Specific examples of arrhythmias include atrial
ectopic beats, ventricular fibrillation, bundle branch block and intraventricular conduction
Bradycardia - a slow heart beat, i.e., under 60 beats per minute (bpm)
A slow, regular heart rate is characteristic of a healthy, conditioned heart. The beat slows as
cardiac volume, mass and output increase-meaning that the heart's pumping efficiency is
improved. It does not need to beat as fast to circulate the same blood volume as an
unconditioned heart. Resting bradycardia is one component of the normal adaptations occurring
in persons who regularly perform endurance training-a condition termed Athletic Heart
Tachycardia - a rapid heart beat, i.e., over 100 bpm
The immediate cardiac response to exercise generally includes a regular tachycardia because of
the need for greater oxygen delivery to tissues. This increase is relatively less in a
conditioned heart as compared to an unconditioned heart.
Coronary Arteries - vessels that supply blood to the heart muscle
Most Coronary Artery Disease (CAD) is due to insidious build-up of deposits within the coronary
arteries (Coronary Atherosclerosis) that abruptly disrupts blood flow to the heart muscle.
Compromised blood flow can cause sudden loss of heart function (Cardiac Arrest) and death
(Sudden Cardiac Death). Atherosclerosis-the process by which fats, cholesterol, calcium and
other substances accumulate in a vessel's lining-can occur in any artery. Risk factors include
poor physical fitness, hypercholesterolemia (high cholesterol) and high triglyceride blood
levels-not a problem for most runners.
Other less common forms of CAD may affect runners. Coronary Artery Spasm can occur in a normal
coronary artery without apparent cause (idiopathic) and reduce or stop the blood flow to a part
of the heart. Coronary Artery Anomaly (CAA) is a malformation present from birth (congenital)
in which the coronary artery grows on the wrong side of the heart, often between the pulmonary
artery and the aorta.(4) During exercise, both the pulmonary and aorta dilate. In an athlete
with CAA, dilation can squeeze the coronary artery blocking blood flow and causing sudden
Heart Murmur - an abnormal heart sound
Heart valve defects are the most common cause of heart murmurs-either valves between the heart
chambers (e.g., Mitral Valve Disease) or valves in the vessels leading to/from the heart (e.g.,
Aortic Valve Disease). Less common causes include holes in the wall (Septum) between heart
chambers (e.g., Atrial or Ventricular Septal Defect). Murmurs can be acquired (e.g., after
severe fever) or congenital (e.g., septal defects). Depending on the underlying cause and
severity, heart murmurs can have different sounds, intensity and timing within the beat. The
abnormal sounds result from aberrant blood flow as the heart pumps. As example, in Mitral
Insufficiency blood leaks backward through the mitral valves, which separate the left ventricle
from the left atrium. The structural defect underlying a murmur compromises the heart's
efficiency-it must work harder to circulate blood. With time, heart enlargement, changes in
blood pressure, arrhythmias and cardiac failure can occur.
Symptoms of cardiac disorders can be insidious, vague, non-specific-even absent! Any of the
following should raise concern meriting professional medical evaluation. (2,3,4)
- Familial history of cardiac disease.
- Recurrent fatigue, weakness, dizziness, disorientation, difficult (dyspnea) or
uncomfortable (orthopnea) breathing, and/or chest pain-particularly during exercise.
- Severe, constricting chest pain (angina pectoris).
- Cold or blue (cyanotic) skin and/or persistent fluid retention (edema).
- Irregular pulse, sensation of pulsation in the neck, and/or neck vein (jugular)
- Loss of consciousness (syncope).
Even if you feel healthy, the following practices may save your life:
- Know whether your family has history of cardiac disorders.
- Obtain a general physical exam annually, ideally including an electrocardiogram (ECG) and
chest x-ray. Ask the physician for your heart rate, blood pressures and lipid profile.
- Learn how to take your pulse and check it during exercise for rate and regularity. Exercise
within your heart rate target training zone.(5)
- Maintain a health and exercise diary including corresponding environmental factors. If your
health falters, this record will be your and your physician's optimal first-line diagnostic
Even the fittest runners can be vulnerable to heart conditions. Therefore, it is important to
exercise common sense as well as to listen to your body. Be aware of threats to your physical
well being, without being paranoid, and proactively evaluate your susceptibility, without being
obsessive. Indeed, "an ounce of prevention is worth a pound of cure."
Dr. Anne G. Evans, MBA has been a health professional for 25 years and a runner for 30.
Contact Anne at agevansevansassoc.net or 858-729-0115.
Running with a Pacemaker
An RAC member for 13 years, Bob Lafferty, now 70, has been running most of his life despite
nearly 40 years of asthma and allergies. In 1999, his allergies appeared to worsen. When he ran
his chest tightened; he also became dizzy and breathless. About 30 minutes into his run,
symptoms resolved although fatigue set in. Lafferty sought medical assistance-repeatedly. Three
specialists told him he was experiencing exercise-induced asthmatic bronchiospasm and
prescribed medications without benefit. Persistence paid off, however. A fourth specialist
suspected cardiac disease. Treadmill stress testing and 48-hour cardiac Holter monitoring
revealed an abnormally slow, irregular heart rate.
On March 27, 2003, a cardiac pacemaker was surgically placed inside Lafferty's chest to correct
the disorder. He resumed running two weeks later, hardly skipping a beat in his training
program. Lafferty now looks forward to becoming a marathoner.
- Stedman, T.L. (2000). Stedman's medical dictionary (27th ed.). Baltimore : Lippincott
Williams & Wilkins.
- Beers, M.H., & Berkow, R.(Eds.) (1999). Merck manual diagnosis & therapy (17th
ed.). Whitehouse Station : Merck & Co. Available web site.
- American Heart Association (2003). Heart and stroke facts [Booklet]. Available web
- Swint, S. (2000, May 1). Sudden death in athletes may sometimes be prevented. WebMD Medical
News Archive. Available web site.
- National Center for Chronic Disease Prevention and Health Promotion. Nutrition &
Physical Activity. (2003, Feb 6). Target heart Rate and estimated maximum heart rate. Available