Cardiomyopathy in Alström Syndrome
Alström Syndrome can cause the heart muscle to pump less efficiently, known as cardiomyopathy. This occurs in about 40% of infants with Alström and often recovers, although not completely, and can re-occur in later life. Other causes of cardiomyopathy, such as viruses may be suspected until other signs of Alström develop, for example:
- “Wobbly eyes” (nystagmus)
- Photophobia (dislike of light)
Cardiomyopathy can also occur during adolescence when the outcome may not be so good. It is often misdiagnosed as asthma in children and young people because it can cause breathlessness and wheeze.
The cause of Alströms cardiomyopathy is an area of ongoing research. It is a different condition from ischaemic heart disease, which is caused by problems with the blood supply to the heart and is also different from diabetic heart disease. In Alströms the heart muscle develops lots of small fibrosis scars, myocardial fibrosis, usually in a patchy manner. In infants the heart may stretch or “dilate”, but in most patients the fibrosis tissue makes the heart stiff and inflexible, termed “restrictive” cardiomyopathy. Alströms cardiomyopathy affects both the right and left sides of the heart, which is important as treatment may differ depending on which side is more severely affected. Effective treatments to improve symptoms have included:
- Angiotensin converting enzyme (ACE) inhibitors
If right heart fibrosis predominates then either of the following are more effective:
It is important to recognise Alströms cardiomyopathy early, so treatment can be started promptly. Alström Syndrome UK charity recommend that patients who have had cardiomyopathy should have annual cardiac review, with an echocardiogram (echo) a painless ultrasound scan which looks at the structure and function of the heart and an ECG (electrocardiogram) which traces electrical activity in the heart. Ideally blood oxygen levels should also be monitored, together with exercise capacity. The role of blood hormone tests and cardiac MRI scanning is being evaluated.
Alström Syndrome UK charity also recommends that even if patients have not had cardiomyopathy they should have annual cardiac review with a detailed discussion of exercise capacity and an ECG. Any hint of the following should trigger an echo:
- Development of asthma
- Change in ECG
It is helpful if the person doing the echocardiogram knows to look for evidence of “restrictive” cardiomyopathy because the signs are often subtle. New echo techniques (Tissue Doppler) will improve this.
Both patients and their doctors should be aware that Alströms cardiomyopathy can happen suddenly and patients are vulnerable during intercurrent illness and surgery. At these times, close monitoring is essential and expert advice should be sort as needed.
Media Review: August 2015
Next Review: August 2017