What are the life expectancies with aortic valve stenosis?
Aortic valve stenosis is often a chance finding, since the heart adapts and even in severe cases it is possible that no or only minor symptoms occur. It is possible that over the years the valve narrowing will increase only very slightly or not at all. For this reason, the life expectancy of an ill patient must always be considered individually.
However, one can make statements about the average life expectancy if the symptoms remain untreated. If angina pectoris (chest tightness) occurs, this would be about 5 years. Syncope (short-term loss of consciousness) reduces the average life expectancy to approx. 3 years and in the case of heart failure with congestion of the lungs up to pulmonary oedema, an average of 2 years can be expected if left untreated. In general, the earlier one starts treatment, the less damage is done to the heart and the better the life expectancy.
Since the symptoms of aortic valve stenosis often occur in the late stages of the disease, the diagnosis of aortic valve stenosis is also often made relatively late. In addition to questioning the patient (anamnesis) and physical examination, the attending physician can listen to the heart with a stethoscope to make a diagnosis. During this process, flow changes that indicate aortic valve stenosis, so-called heart murmurs, can often be heard.
The best way to diagnose aortic valve stenosis is by means of imaging techniques. Especially the examination with an ultrasound machine is often used to diagnose the disease. In this case, one also speaks of echocardiography.
Also relevant are ECG examinations and X-rays, which can be used to show the consequences of aortic valve stenosis. The cardiac ultrasound examination is referred to by physicians as echocardiography, cardiac echo or often abbreviated “echo” and is the so-called gold standard when it comes to diagnosing aortic valve stenosis. Gold standard means that an examination is generally considered the best diagnostic procedure for the disease in question, and all other procedures must be measured against it.
This ultrasound examination of the heart can make the heart and the heart valves visible either through the oesophagus or from the outside through the chest and thus helps to make a reliable diagnosis of the disease. The so-called “swallow echo” (transesophageal echocardiography, TEE), which is performed via the esophagus with the aid of a flexible tube, is usually performed under a mild anaesthetic. The diameter of the valve can be measured on the monitor of the device.
If the aortic valve is narrowed, the diameter is significantly reduced. It is also possible to measure the thickness of the muscle of the left ventricle, which is often massively enlarged in aortic valve stenosis. During the physical examination, the physician listens to the heart in addition to other measures.
Aortic valve stenosis is often conspicuous by a characteristic heart murmur, which is caused by the existing narrowing in the area of the valve. This heart murmur is described as a spindle-shaped mesosystolic, which can be heard particularly well between the second and third ribs. Spindle-shaped means that the tone starts quietly, then becomes louder and then quieter again towards the end, i.e. like the shape of a spindle.
Mesosytolic means that the sound starts in the middle of the systole, i.e. in the phase when the heart chambers contract and the blood is pumped into the circulation. In some cases, a clicking sound is heard before the actual heart murmur begins (ejection click). The classification of aortic valve stenosis into degrees of severity is handled differently.
The classification presented below is the most common one in Germany. The graduation of aortic valve stenosis ranges from mild to moderate to severe and critical. In order to differentiate between these degrees of severity, three criteria are generally applied.
The first criterion is the so-called mean systolic pressure gradient. Since the narrowing of the aortic valve reduces the transition of the left ventricle into the aorta, the pressure which is generated in the ventricle and in the aorta behind the aortic valve is not the same. The higher the stenosis, the higher the pressure gradient.
Like blood pressure, the pressure gradient is given in the unit mmHg. While a mild stenosis has a pressure gradient of up to 25 mmHg, this is between 25 and 40 mmHg for a moderate stenosis. A severe stenosis is considered to be a severe stenosis if the pressure gradient is above 40 mmHg.
A critical aortic valve stenosis exists if the pressure gradient is above 70 mmHg. The second criterion that is used for the graduation of aortic valve stenosis is the measured valve opening area (). This is usually measured by means of a cardiac echo and is given in the unit “cm2”.
The smaller the valve opening area, the higher the degree of aortic valve stenosis. While a valve opening area of more than 1.5 cm2 is referred to as a mild stenosis, the area of a moderate stenosis is between 1 and 1.5 cm2. A valve opening area of less than 1.0 cm2 is referred to as a severe stenosis.
A very critical aortic valve stenosis is present if the valve opening area is less than 0.6 cm2. The third criterion for assessing the severity of the stenosis is the patient’s symptoms. While a mild aortic valve stenosis is always accompanied by no symptoms and a moderate stenosis is usually also asymptomatic, severe aortic valve stenosis is usually accompanied by the typical symptoms of the disease. A very critical stenosis almost always shows symptoms. (see above)