Can we differentiate “Sarcomeric vs non Sarcomeric HCM” by Echocardiography ?

Can we differentiate “Sarcomeric vs non Sarcomeric HCM” by Echocardiography ?

September 4, 2024 by dr s venkatesan

Echocardiography, the ultrasonic imaginative and prescient, with which we’re capable of immediately visualize the center is a monumental discovery ,gifted to us by Edler & Hertz within the Fifties. These excessive frequency sound interacts with myocytes in a wide range of methods like penetration ,reflection, ab & adsorption, again scattering and so forth. It has additional developed , on the tissue stage diagnostic like 3D speckle ,and pressure and so forth .

With all all these developments ,how good is echocardiography in ruling out (or in) reversible /treatable HCM mimickers or their molecular subsets.

Recognizing non-sarcomeric Hypertrophic Cardiomyopathy (HCM) by echocardiography is one such activity .It may be difficult, however listed below are some clues to assist:

1. Uncommon hypertrophy patterns: Non-sarcomeric HCM could exhibit atypical hypertrophy patterns, similar to:
   • Mid-ventricular hypertrophy
   • Apical hypertrophy
   • Hypertrophy in the suitable ventricle
2. Absence of systolic anterior movement (SAM): In contrast to sarcomeric HCM, non-sarcomeric HCM could not exhibit SAM of the mitral valve.
3. Regular or lowered left ventricular outflow tract (LVOT) gradient: Non-sarcomeric HCM could not have a big LVOT obstruction.
4. Presence of fibrosis or scar tissue: Search for indicators of fibrosis or scar tissue on echocardiography, similar to:
   • Shiny or patchy look within the myocardium
   • Elevated echogenicity
5. Irregular myocardial texture: Non-sarcomeric HCM could exhibit an irregular myocardial texture, similar to:
   • Speckled or “ground-glass” look
6. Different structural abnormalities: Some non-sarcomeric HCM instances could exhibit different structural abnormalities, similar to:
   • Mitral valve abnormalities
   • Tricuspid valve abnormalities
   • Proper ventricular abnormalities

Ref : Sarcomeric versus Non-Sarcomeric HCM June 2023 Cardiogenetics 13(2):92-105

Some particular echocardiographic options of non-sarcomeric HCM embody:

• Fabry illness: Usually exhibits a “binary” look of the myocardium, with a brilliant and darkish sample.
• Amyloidosis: Usually displays a “granular glowing” look of the myocardium.
• Cardiac sarcoidosis: Might present a “starry sky” look resulting from myocardial fibrosis.

Please bear in mind, that echocardiography needs to be complemented with scientific analysis, genetic testing, and different diagnostic instruments to substantiate the analysis.

Amyloid -HCM coexistence

Medical pathology is rarely a pure science.It will possibly make our evaluation topsy turvy at any second .One such uncommon phenomenon is amyloid getting deposited in a affected person with classical inherited HOCM. (Boyangzi Li, Cardiac AA amyloidosis in a affected person with obstructive hypertrophic cardiomyopathy,
Cardiovascular Pathology, Quantity 48, 2020,)

A touch upon deep genetic profiling

Genetic research in HOCM are academically thrilling  and professionally gratifying. From the affected person perspective, it offers  a possibility to deal with any reversible or treatable enzyme problems(Ref 1 Migalastat for Fabry’s illness & Tifamidis and Patisiran in TTR Amyloidosis) .

However, the advantages of deep genetic testing needs to be fastidiously harvested as there’s a troubling commerce off, because of the hitherto hidden prognostic anxiousness, these genetic breakthroughs carry alongside.

Ultimate message

Opposite to the idea , a fastidiously interpreted echocardiography together with scientific profile will be capable of recognise sarcomeric HCM in most conditions.However, it’s nonetheless weak in ruling in a non- sarcomeric HCM.

Reference

1.McCafferty EH, Scott LJ. Migalastat: A Assessment in Fabry Illness. Medication. 2019 Apr;79(5):543-554. doi: 10.1007/s40265-019-01090-4. Erratum in: Medication. 2019 Aug;79(12):1363. doi: 10.1007/s40265-019-01166-1. PMID: 30875019; PMCID: PMC6647464.

2.The small interfering mRNA drug , is an interstitial protein excretory drug in TTR amyloid.