A phonocardiogram is a recording of heart sounds that can be represented visually on a phonocardiograph chart. This can be useful for making a recording of abnormal heart sounds for future reference, including follow-up to determine if a patient is responding to treatment. Such testing can also be valuable in the detection of subtle and sub-audible variations in heart sounds that are indicative of a medical problem which might not otherwise be identified. Many hospitals have the ability to produce high fidelity recording of heart sounds, as do specialty clinics focusing on cardiac care.
Some stethoscopes have a phonocardiogram mode, while in other cases a special device may be used for the recording. A medical provider can listen to the heart with a stethoscope, make a recording, and order additional testing like an electrocardiogram to record the electrical impulses associated with heart activity. All of this information can be useful in the evaluation of a patient with a suspected heart problem, whether it is a benign abnormality or a serious issue that requires medical treatment.
Looking at the visual representation of the audio information collected during a phonocardiogram, a medical practitioner can look for abnormal spikes or dips in sound that indicate unusual noises are occurring. Heart sounds are associated with the vibrations caused by movement of the heart valves, and can include a variety of murmurs as well as turbulence as blood moves through the valves. When an unusual finding shows up, the care provider can amplify it to listen more closely, slow it down, repeat it, and otherwise manipulate the sound to get a clearer understanding of what is happening.
In a patient who sounds normal on physical auscultation with a stethoscope, where the doctor listens to the heart sounds manually, sometimes a phonocardiogram will show something else. Some problems with the heart show up on the sub-audible level and won’t be identified unless the practitioner uses more advanced diagnostic tools. For patients with audible abnormalities, a recording helps a provider isolate the sound to learn more and is also useful for follow-up; if a murmur sounds like it is getting worse, for example, the doctor can pull the recording from a prior session to compare.
Generally, the phonocardiogram is a noninvasive procedure that shouldn’t cause any pain or discomfort. It may be part of a cardiac workup which could include other procedures, some of which may be more invasive; in some imaging studies, for example, a tracer dye is used to highlight blood so it can be seen moving through the heart. Patients with concerns about a medical evaluation for a heart problem can ask about the procedures, how long they should take, and whether hospitalization will be required.
