4A. PERSONAL HISTORY: HAVE YOU BEEN TOLD THAT YOU HAVE A HEART MURMUR?
To determine the importance of a positive answer to this question, the following questions should be asked:
1. Has the murmur been present since birth, and is it still present?
Athletes with congenital murmurs may remain asymptomatic for life, particularly if there is no associated pathologic condition. However, ventricular or atrial septal defects, patent ductus arteriosus (PDA), bicuspid aortic valves, and other causes of heart murmur may have long-term consequences and require correction.
2. Has anyone told you that the murmur is physiologic or pathologic?
A documented prior medical evaluation, particularly if imaging has been performed, can facilitate decisions regarding athletic participation. If the studies are of questionable quality or not available, reevaluation may be necessary.
3. Are there other associated symptoms such as chest pain, shortness of breath, dyspnea on exertion, and/or palpitations?
The presence of cardiovascular symptoms such as chest pain, dyspnea, and palpitations can be indicative of an underlying cardiac pathology. Chest pain due to microvascular disease is a feature of HCM.
5. Does anyone in your family have a heart murmur?
Familial HCM is an autosomal-dominant trait and one of the most common causes of sudden death in athletes. Other congenital abnormalities that cause murmurs such as Marfan syndrome can cluster in families as well.
PHYSICAL EXAMINATION: IS A HEART MURMUR PRESENT ON PHYSICAL EXAMINATION?
The Cardiovascular Examination of the Athlete
The cardiac examination should be performed in a stable state and not in the recovery period from an extended period of exercise or competition and in a quiet, comfortable setting with attention given to privacy and room temperature. The examination should be conducted sitting and supine with maneuvers like the Valsalva maneuver, standing, and squatting added if a significant murmur is detected.
Physiologic and morphologic adaptations of the aerobically trained athlete’s heart include slow heart rate, systolic ejection flow murmur at the upper, left sternal border, a third heart sound, lateral displacement of point of maximal impulse, and hyperdynamic carotid pulses. Athletes predominantly engaged in isometric training (weightlifters) will not exhibit these changes.
The examination of the athlete can be challenging because of these physiologic adaptations. Cardiac enlargement by visual examination (apical movements) and palpation (lateral displacement) can simulate the examination of patients with cardiomyopathies or heart failure. The loudest third heart sounds you will ever hear will be in athletes, and they are physiologic when occurring at low heart rates. This contrasts to the third heart sounds in patients with heart failure where they occur at fast heart rates (called “gallops” because of the cadence). Furthermore, third heart sounds in athletes are not related to position, while in patients with heart disease, the S3 gallop is loudest in the supine position.
Even in the resting state, systolic flow murmurs can be appreciated in athletes, but they are soft, occur early in systole, and radiate upward rather than laterally toward the apex. While fixed splitting of the heart sounds can be appreciated in the supine position in nonathletes, this splitting is particularly noticeable in athletes. Thus, the finding of fixed splitting should only be considered abnormal if heard in the sitting or standing position.
Any diastolic murmur is abnormal whether or not there is an accompanying systolic murmur. The most common cause is aortic insufficiency (or regurgitation, abbreviated AI or AR). Early AR is best appreciated at the upper left of the sternum, with the athlete in the seated position, during forced expiration and leaning forward. A trick is to carefully listen after the second heart sound to focus attention at the correct time. Since AR can be difficult to appreciate, it is helpful to listen even more carefully when the following occur:
- A systolic murmur.
- Wide pulse pressure (>50 mm Hg) or a diastolic pressure of 50 mm Hg or less.
- Hyperdynamic carotid pulse.
While AR is the most common cause of a to-and-fro (systolic/diastolic) murmur in athletes, another cause is PDA. This is a congenital abnormality more often encountered than other congenital abnormalities in athletes because athletic performance can be quite normal if the shunt is small.
Characteristics that increase the likelihood of systolic murmurs being pathologic include the following:
- Greater than grade 2/6 intensity
- Lateral rather than upward radiation
- Occurrence in mid-systole or late systole rather than in early systole
- Accompanied by a click in mid-systole or late systole
- Any murmur that becomes louder with the Valsalva maneuver (best performed supine with your hand on abdomen and telling the athlete to push against your hand while continuing to breathe)
Other auscultation abnormalities include a third heart sound during tachycardia or fixed splitting of the second heart sound in the seated position. Sinus tachycardia at rest is abnormal in an aerobically trained athlete, and if not easily explained (recent workout, fever, etc.), further workup may be indicated, particularly if accompanied by any symptoms.
Case 1: Tennis Player with Unexplained Sinus Tachycardia
A 20-year-old White female tennis player presented with tachycardia and shortness of breath while going to classes. She normally performed at the top level of competitions but was out of season at the time. She had been symptomatic for nearly a week and presented late in the day after classes. An examination yielded unremarkable results, and she was afebrile, with blood pressure 120/70 and HR of 100 bpm, although S2 seemed to be louder than S1 even at the apex. She was on birth control pills and had just recovered from a leg injury. There was no leg tenderness or swelling. Blood tests were ordered (complete blood count, thyroid function), and a Holter monitor, placed. The Holter was read the next day and was unremarkable except for an average heart rate of 100 bpm with maximum of 140 bpm during light exercise. Laboratory test results were normal. An echocardiogram showed a dilated right ventricle (RV), elevated pulmonary artery (PA) pressures, and normal left ventricle (LV) function. Primary pulmonary hypertension was considered, but she was sent for a computerized tomography chest angiogram lung scan, which revealed pulmonary embolus. She was started on heparin and then treated with Coumadin with gradual recovery. She was found to have factor V Leiden genotype.
Key Point: Sinus tachycardia may be the only finding with a pulmonary embolus.
Case 2: Baseball Player with Continuous Murmur
During mass screening, a cardiology fellow noted a systolic murmur while examining a 19-year-old White male baseball player. The athlete was asymptomatic and had normal ECG. The fellow performed screening echocardiogram on site, which was considered normal, and the athlete was cleared for participation. As formality, the supervising cardiologist auscultated the athlete and noted a to-and-fro continuous murmur. Echocardiogram and cardiac catheterization revealed PDA with significant right-to-left shunting. The athlete was offered surgical or percutaneous correction.
Key Point: Continuous (systolic and diastolic) and diastolic murmurs are always due to cardiac pathologic lesions. The continuous murmur of PDA is described as a continuous “washing machine” type murmur; best appreciated in the second left intercostal space. A scanning echocardiogram will miss it.
Case 3: Soccer Goalie with Fixed Split of Second Heart Sound (S2)
A 21-year-old African transfer student complained that he could not “keep up” with his peers during his PPE for collegiate soccer. Upon examination, he had a fixed split S2 while sitting and standing. His ECG results exhibited right axis deviation and incomplete right bundle branch block. His echocardiogram results appeared to be normal, but a bubble study was added, showing a secundum atrial septal defect permitting an interatrial left-to-right shunt. A right-to-left shunt would have suggested significant pulmonary hypertension and Eisenmenger syndrome. He also had a systolic ejection murmur at the left upper sternal border from increased flow across the pulmonary valve. Catheterization revealed significant shunting with high risk of developing pulmonary hypertension. He was offered surgery or percutaneous closure and opted for the latter.
Key Point: Secundum atrial septal defects are the most common type of atrial septal defect (ASD) and the only defects amenable to percutaneous closure.
Case 4: Football Lineman with Chest Pain and Systolic Murmur
A 20-year-old African-American freshman football lineman was noted to have systolic murmur during PPE. The murmur increased with Valsalva maneuver; his carotid pulse was brisk, and his apical impulse laterally displaced. Upon further questioning, he reported vague exertional chest pain. Echocardiogram results showed mild septal hypertrophy (14 mm), but a magnetic resonance imaging (MRI) demonstrated significant asymmetric hypertrophy at the distal septum.
Key Point: The Valsalva maneuver can decrease LV volume and increase mitral flow obstruction to make the diagnosis of HCM with obstruction. Care must be taken to do it properly without breath holding. HCM can be present without such obstruction, and a systolic murmur only be due to hyperdynamic flow not affected by Valsalva. HCM without obstruction can be missed with echocardiography as much as 50% of the time due to focal hypertrophy that is best seen with MRI.