How Is Heart Valve Disease Diagnosed?
The heart’s efficiency as a pump depends on all of its parts functioning properly. The valves are an indispensable part of that physiology. All of the ways of evaluating the heart can play to advantage in diagnosing valvular heart disease, with echocardiography being the most informative in determining functional compromise in the atria, ventricles, or both.
All heart valve diagnostics begin with an in-depth history and a thorough physical exam when symptoms of chest pain, palpitations, dyspnea, or fainting result in a patient being evaluated for valvular heart disease.
A family history can reveal congenital proclivities toward structural heart defects. A drug history can highlight valve risk from anorectic drugs used in weight management, ergot derivatives for migraines, and illicit drugs such as MDMA (ecstasy). A childhood history of rheumatic fever can be a crucial clue to chronic valve disease (mitral, aortic, and tricuspid). Social history that includes tobacco products and alcohol is also essential. Obvious pertinent history includes a pre-established diagnosis of heart disease or valve repair/replacement.
Although edema, wheezing, or fatigue are easy to identify, the quintessential test that moves the diagnostics into the specific pursuit of valvular dysfunction is the auscultation of the heart. There are two easily heard heart sounds that are consistent with normal valvular function. There are also some subtle additional sounds that can be evoked with respiration and are normal. Valvular disease, however, makes the heart much noisier than it should be, when the turbulence of blood flow is created by the dysfunctional flow dynamics of valvular disease. These extra sounds are called heart murmurs, which are heard as whooshing, blowing sounds.
The positive findings don’t stop there, as other sounds that are pertinent include clicks from mitral valve prolapse, the 3rd heart sound seen in heart failure, or a 4th heart sound from aortic stenosis or mitral regurgitation.
The simple 2-dimensional chest X-ray which shows the cardiac silhouette in contrast against the aerated lung fields can demonstrate gross enlargement of the heart and pulmonary edema, for example, as a result of obstructed flow at the tricuspid valve.
The electrocardiogram (ECG) is a graphic recording of the wave of electrical impulses along the contraction vector over time, and it can demonstrate arrhythmias commonly seen in valvular disease.
- Cardiac echogram: Echocardiography is the procedure of choice in evaluating valvular heart disease and it defines the standard of care for it. It uses ultrasound to study the atrial and ventricular wall motion which is impacted by the flow abnormalities caused by valvular heart disease. The timing of cardiac sequenced events can categorize arrhythmias and the timing or delay of valvular function which can provoke them. Doppler velocimetry can determine any flow dysfunction. There are two types of echocardiography used:
- Transthoracic echogram (TTE): which is via a doppler transducer placed on the patient’s chest.
- Transesophageal echogram (TEE): which involves a transducer placed in the esophagus (gastrointestinal endoscopy). It eliminates a lot of the “clutter” of structures between the skin and the heart and so provides superior delineation of pathology. It is invasive, as compared to TTE and it requires sedation; due to its invasive nature, it also carries small risk of esophageal perforation or bleeding.
This can be used to assess exercise capacity and the need for valvular intervention (surgical repair or replacement).