A cardiomyopathy is suspected when the myocardium is abnormal without an explanation outside it. The presentation is often non-specific — breathlessness, chest pain, palpitations, or syncope (fainting) — and many people have few or no symptoms, so the problem may first appear as an incidental finding, during family screening, or on an ECG done for another reason. Because several cardiomyopathies carry specific treatment, the workup aims not only to describe the dysfunction but to identify its cause.
What the evaluation includes
Current European guidance recommends a systematic, multiparametric evaluation for anyone with suspected or confirmed cardiomyopathy: clinical assessment, a family history, ECG, Holter monitoring (continuous ambulatory ECG recording), laboratory tests, and imaging with more than one modality. The phenotype at presentation — the pattern of hypertrophy, dilatation, dysfunction, or scar — organises that evaluation, and tissue characterisation is what turns a phenotype into an aetiological diagnosis.
Is it the muscle, or something acting on it?
The first question is whether the ventricle is diseased in itself or responding to a load from outside. When dysfunction and the late gadolinium enhancement pattern — the scar visible after contrast imaging — follow a coronary territory, ischaemia is the likely explanation. Hypertension, a valve lesion such as aortic stenosis, and congenital malformation are external explanations for hypertrophy or dilatation. Disease that is diffuse and does not respect a coronary territory points toward the muscle itself.
Family history and genetic testing
A three- to four-generation family tree is part of the evaluation for every patient, because the pattern of inheritance may point to the cause and because relatives can be at risk. Genetic testing is recommended where it can confirm the diagnosis, inform prognosis or treatment, guide reproductive decisions, or open cascade testing — testing relatives in turn — of relatives who would otherwise need long-term surveillance. A relative who carries a disease-causing variant may show no phenotype at first, so surveillance continues even when the initial ECG and imaging are normal.
When the echocardiogram understates the disease
A recurring problem is the disproportion between a reassuring echocardiogram and severe tissue disease. Mild hypertrophy with preserved ejection fraction on echo can coexist with pancardiac infiltration — deposit throughout the whole heart — on mapping. The echocardiogram remains the frontline tool — available, inexpensive, real-time, with Doppler filling pressures and strain — but a mild echo never excludes diffuse tissue disease.
Advanced age alone should not deny the workup: diffuse disease can hide behind a mild echocardiogram at any age, and a diagnosis can matter for the family as well.
Is there a treatable cause?
Fabry disease, light-chain amyloidosis, transthyretin amyloidosis, and obstructive hypertrophic cardiomyopathy each carry specific therapy, so finding them changes management rather than only naming the disease. Finding them depends on looking at the tissue itself.
What the tissue says
Tissue imaging with cardiac magnetic resonance (CMR) reports the T1 and T2 relaxation times of the myocardium — measures that change with its composition — its extracellular volume, the fraction of the wall that is not cells, and the pattern of late enhancement. Together these narrow the differential before any invasive step, because fibrosis, infiltration, storage, and oedema each leave a different combination. CMR belongs early in the workup rather than at its end. Oedema marks an active process; enhancement without oedema marks established scar or deposit.
When imaging and laboratory tests still leave the cause unclear but point to inflammation, infiltration, or storage, endomyocardial biopsy — a tissue sample taken from inside the ventricle — is the next step. Before that, the question is what each sequence actually measures, which the cardiac MRI note sets out.