The heart does hard work – continuously pumping blood into the body’s circulatory system, nearly 300 liters an hour. A powerhouse that is prone to malfunctions – cardiovascular diseases are the most common cause of death in Germany. Proper diagnostics are important for prevention and adequate therapy. But what heart examinations are there and how do they work? Learn more about the procedure of a cardiac examination here.
Heart examination: a conversation at the beginning
The examination of the heart does not begin with sophisticated equipment, but with a conversation (anamnesis). Experts believe that a majority of all tentative diagnoses can be made with speech and hands. Often the patient’s medical history is so typical that with targeted questions from the experienced physician, the suspected diagnosis can already be made and alternative diagnoses can be ruled out. Pre-existing conditions, family illnesses, medications and risk factors are also important. In addition, there are the findings that the physician obtains by looking at the patient and during the physical examination. Special tests are then often used to refine the diagnosis and draw up the treatment concept or to monitor treatment. In some cases, they can be coupled directly with therapeutic measures. Which apparative tests are used depends on the suspected diagnosis and question.
Basic diagnostics for examination of the heart.
Basic diagnostics for cardiac examinations include various methods. These include:
- Inspection (visual examination) and palpation (palpation).
- Blood pressure measurement
- Percussion (tapping)
- Auscultation (listening)
- Examination of the vessels
- ECG (cardiac waveform)
- Laboratory tests
In the following, we present the various examination methods in more detail.
Inspection and palpation in cardiac examinations.
The physical examination is usually performed on a sitting or lying patient with the upper body undressed. Externally visible signs of disease (inspection) include water retention, blue lips and fingers, changes in fingernails, pulsations, facial flushing, or skin changes on the legs. During palpation, the physician checks the frequency, rhythm, and character of the pulse, as well as the cardiac impulse on the left rib cage. The vein in the neck (jugular vein) provides important information about the return flow of blood to the right heart.
Blood pressure measurement and percussion
Blood pressure measurement is also an indispensable tool. It should be performed on both arms and several times. Tapping (percussion) the chest can be used to determine the approximate size of the heart – although imaging techniques are better for this.
Auscultation: listening with a stethoscope.
Auscultation, or listening with a stethoscope, is an important examination step. The trained person can already use it to detect many cardiac changes, especially cardiac defects. Assessed are:
- Heart rate: normal, too fast, too slow?
- Heart rhythm: regular, irregular, extra beats?
- Heart sounds: do 1st and 2nd heart sounds sound normal or are they altered? Are extra sounds present?
- Heart murmurs: are there any extra murmurs? When do these occur and how do they sound?
For the four heart valves and their changes, there are different areas where they can be best listened to. That’s why the doctor places his stethoscope on different areas, letting the patient assume different positions if necessary, and asks him to breathe in deeply, then exhale or hold his breath.
Examination of the vessels
Because the heart and vessels are related, the latter are also part of the clinical examination. Because vascular changes are more likely to be found on the legs than the arms, the skin color (pallor, edema, cyanosis), leg circumference, skin, and visible vessels such as varicose veins are assessed primarily there. The pulses are palpated and listened to on the arms, abdomen and legs. If there is constriction, flow sounds are often present. If there is a suspicion of diseases of the arteries or veins, one can connect various tests that can be performed without much effort and tools (walking test, positioning test).
ECG: measurement of the cardiac current
Measuring the heart current curve (ECG) at rest is part of basic diagnostics. If necessary, stress ECG or long-term ECG follow.A catheter examination can be used to derive an ECG directly from the heart (electrophysiological examination = EPU), which is necessary in some cases of cardiac arrhythmias.
Laboratory examinations of the heart
Depending on the question, various laboratory values are determined in the blood, but these usually only provide indications of causes or risk factors. For example, blood count, coagulation, sugar, fats, liver and kidney values, minerals and thyroid values can be important. Specifically for heart disease or suspected heart attack, the following laboratory values are determined:
- Lactate dehydrogenase (LDH: infarction, myocarditis).
- Creatine kinase (CK: cardiac muscle damage).
- Troponin ( myocardial infarction) and
- Brain natriuretic peptide (BNP: myocardial insufficiency).
Elevated C-reactive protein (CRP) is discussed as a prognostic parameter for myocardial infarction risk.
Ultrasound examinations of the heart
Sonography is an important procedure for imaging the heart and blood vessels. The advantage is, on the one hand, that ultrasound does not cause radiation exposure and is painless, and on the other hand, that it allows the heart to be observed and assessed in full action. The normal ultrasound images are called echocardiography or casually “cardiac echo”. This is used to look at the individual structures from different angles from the chest wall and to examine the heart function. The ventricles, the heart valves and the aorta can be seen. Heart size can be assessed, whether the heart muscle contracts equally well everywhere, and whether the heart valves open and close. The amount of blood ejected can also be estimated, and fluid collections in the pericardium can be seen.
Other forms of sonography
With an additional device, Doppler and duplex sonography can be used to make the blood flow visible in color and audible. Ultrasound images can also be taken under stress, for example on a bicycle or after medication has been administered (stress echocardiography). These may reveal pathological changes that are not otherwise visible. In addition, the ultrasound probe can also be inserted into the esophagus via a thin tube (transesophageal echocardiography = TEE) or directly into blood vessels via a small catheter (intravascular ultrasound = IVUS). TEE allows better visualization of valves and atria, and IVUS allows assessment of calcifications of the vessel walls.
Other imaging modalities
A chest x-ray (chest x-ray) provides information about heart size and shape and may show calcifications. However, it is quite nonspecific. Magnetic resonance imaging (MRI) allows the heart to be visualized in three dimensions and in full function with very accurate images; additional information about the heart muscle tissue can be obtained after administration of contrast material. However, since the procedure is very expensive, it is not yet used on a large scale. The informative value of computed tomography (CT) is limited, even with newer multislice techniques, because cardiac motion causes blurring. Although it can be used to determine changes in the vessel wall directly and at an early stage, as well as the calcium content of the coronary vessels – the extent to which the latter correlates with the risk of myocardial infarction (“calcium score”) is still controversial.
Coronary angiography as a cardiac examination
The most accurate results about the condition of the coronary arteries are provided by coronary angiography, a combination of cardiac catheterization and x-ray imaging. Both for accurate diagnosis of suspected vascular disease and in preparation for heart surgery, it is increasingly performed in specially equipped laboratories. If necessary, the procedure can be coupled directly with balloon dilatation of the vessel (PTCA) or insertion of a support grid (stent). In addition to calcifications and narrowing of the coronary arteries, cardiac muscle function, the valves between the left atrium and ventricle (mitral valve) or left ventricle and aorta (aortic valve), and the filling capacity of the ventricles can also be assessed and it can be determined whether there is a bulging (aneurysm) of the heart wall or artery.
Nuclear medicine examinations
Myocardial scintigraphy can be used to assess the function of the heart muscle – it is not always clear whether a narrowing really leads to the relevant circulatory disturbance.For this purpose, a radioactively labeled substance is injected after a load and observed by means of a gamma camera how it is absorbed in the heart muscle – the better the blood flow, the higher the accumulation. The radiation dose corresponds to a conventional X-ray image, and the informative value is comparable to MRI. Radionuclide ventriculography directly visualizes the beating of the heart chambers with radioactive substances.