Name: Numer: Study group:
This text was supported by project FRMU no. MUNI/FR/1552/2015 (Faculty of Medicine, Masaryk University).
Theoretical part
Apex beat and heart sounds
Basic evaluation of heart status done during each total patient’s examination includes
examination of external manifestations of heart function. According to the various senses
employed this examination is divided into four groups:
 Visual (inspection): in meagre students an apex beat can be observed;
 Touch (palpation): an apex beat is palpable in the 4th to 5th intercostals space on the
left medioclavicular line, in healthy people it can be covered by fingertip;
 Tapping (percussion): tapping of heart borders is not a routine examination since it is
inaccurate; exact information on heart size can be obtained by X-ray or
echocardiographic examinations;
 Listening (auscultation): the most important physical method of examination the
heart; the presence and quality of particular heart sounds can be considered, and
pathological heart sounds (murmurs) can be examined and their cause identified
(based on the place and time of their audibility).
The examiner usually approaches the patient from the latter’s right side and examines him/her
in the following positions: supine position, lying on the left side with the patient’s left hand
the below head and in sitting position, possibly in bending forward. This examination is
performed in a silent room and the patient must be in comfortable position and undressed.
In healthy adults, there are two normal heart sounds, often described as a lub and a dup, that
occur in sequence with each heartbeat. The first and second heart sounds are separated by a
brief systolic pause, and second and first heart sounds are separated by longer diastolic pause.
In addition to these sounds, a variety of other sounds may be present including heart murmurs,
adventitious sounds, and gallop rhythms, third and fourth heart sounds.
The first heart sound is initiated at the onset of ventricular systole and reflects closure of the
AV valves. It is the loudest and longest of the heart sounds, and is heard best over the apical
region of the heart. The tricuspid valve sounds are heard best in the fifth intercostal space just
to the left of the sternum; the mitral sounds are heard best in the fifth intercostal space at the
cardiac apex.
The second heart sound, which occurs with abrupt closure of the semilunar valves, is
composed of higher frequency vibrations (higher pitch) and is of shorter duration and lower
intensity than is the first heart sound. The portion of the second sound caused by closure of
the pulmonic valve is heard best in the second thoracic interspace just to the left of the
sternum, whereas that caused by closure of the aortic valve is heard best in the same
intercostal space but to the right of the sternum. The aortic valve sound is generally louder
than the pulmonic valve, but in cases of pulmonary hypertension, the reverse is true. The
nature of the second heart sound changes with respiration. During expiration, a single heart
sound is heard that reflects simultaneous closing of the pulmonic and aortic valves. However,
during inspiration, closure of the pulmonic valve is delayed, mainly as a result of increased
blood flow from an inspiration-induced increase in venous return. With this delayed closure
of the pulmonic valve, the second heart sound can be heard as two components; this is termed
physiological splitting of the second heart sound.
Name: Numer: Study group:
This text was supported by project FRMU no. MUNI/FR/1552/2015 (Faculty of Medicine, Masaryk University).
Figure: Heart sounds (FCG, fonocardiography) in context of ECG and sfygmography (SFG)
A third heart sound is sometimes heard in children with thin chest walls or in patients with left
ventricular failure. It consists of a few low-intensity, low-frequency vibrations heard best in
the region of the cardiac apex. The vibrations occur in early diastole and are caused by the
abrupt cessation of ventricular distention and by the deceleration of blood entering the
ventricles.
A fourth, or atrial, sound consists of a few low-frequency oscillations. It is caused by the
oscillation of blood and cardiac chambers as a result of atrial contraction.
Heart murmurs are generated by turbulent flow of blood. Murmurs may be physiological
(benign) or pathological (abnormal). Abnormal murmurs can be caused by stenosis restricting
the opening of a heart valve, resulting in turbulence as blood flows through it.
Mitral stenosis diastolic murmurs
Tricuspid stenosis diastolic murmurs
Aortal stenosis systolic murmurs
Pulmonic stenosis systolic murmurs
Abnormal murmurs may also occur with valvular insufficiency (regurgitation), which allows
backflow of blood when the incompetent valve closes with only partial effectiveness.
Mitral insufficiency systolic murmurs
Tricuspid insufficiency systolic murmurs
Aortal insufficiency diastolic murmurs
Pulmonic insufficiency diastolic murmurs
The systolic murmurs occur during systolic pauses, diastolic murmurs occur during diastolic pauses.
Apex beat
The apex beat is a mechanical manifestation of heart activity generated by impact of cardiac
apex during ventricular systole to the chest wall. Apex beat can be viewed or palped in the 4th
or 5th intercostal space under the left mammilla and it is better observable in a skinny person.
The apex beat can pathologically shift to the 6th intercostal space in patients with left
ventricular dilatation.