Regression of Left Ventricular Hypertrophy in Obstructive Hypertrophic Cardiomyopathy Following Mavacamten Therapy Assessed by Cardiac Magnetic Resonance.

Presenting Author(s)

• 

  Ana C.P Costa, MD

  MD
  Hospital do Coração
  São Paulo , Sao Paulo, Brazil

Primary Author(s)

• 

  Ana C.P Costa, MD

  MD
  Hospital do Coração
  São Paulo , Sao Paulo, Brazil

Co-Author(s)

• bF

  barbara C. Fonseca, MD

  MD
  Hospital do Coração, Brazil
• BN

  Bruno Novoa, MD

  MD
  Hcor, Brazil
• VM

  Valeria Moreira, MD

  Hospital do Coração - Heart Hospital - HCOR, São Paulo, Brazil, Brazil
• AC

  Adriano Carneiro, MD

  Cardiologist, Cardiovascular Imaging Coordinator
  Hospital do Coração - HCor
  São Paulo, Sao Paulo, Brazil
• CP

  Carlos EE Prazeres, MD

  Doctor
  Instituto Dante Pazzanese de Cardiologia, Brazil
• JB

  JULIANA BELLO, MD

  HCOR, Brazil
• 

  Tiago A. Magalhães, MD, PhD

  Cardiologist
  Hospital do Coração - HCor - Brazil
  Curitiba, Parana, Brazil
• 

  Carlos Rochitte, MD, PhD, FSCMR

  Associate Professor of Cardiology, Academic Coordinator of Cardiovascular Magnetic Resonance and Computed Tomography sector, and Medical Director of the Research Center at Heart Institute, InCor, University of São Paulo Medical School Cardiovascular Magnetic Resonance and Computed Tomography Director at HCOR Senior Medical Leader at Alta Excelência Diagnóstica, DASA, São Paulo
  InCor - Univ. of São Paulo / HCOR - Heart Hospital
  InCor - Univ. of São Paulo
  São Paulo, Sao Paulo, Brazil

Description of Clinical Presentation: A symptomatic patient with obstructive hypertrophic cardiomyopathy (oHCM) presented with marked asymmetric left ventricular hypertrophy and persistent limitation despite optimized medical therapy. Mavacamten, a selective cardiac myosin inhibitor, was initiated to relieve symptoms and reduce obstruction.

Diagnostic Techniques and Their Most Important Findings: Cardiac magnetic resonance (CMR) with cine imaging was performed before and after initiation of mavacamten. Cine-CMR, with its excellent spatial resolution and reproducibility, provided accurate assessment of myocardial morphology and function. Follow-up cine sequences demonstrated a remarkable regression of asymmetric left ventricular hypertrophy, with significant reduction in wall thickness and evidence of structural remodeling. To our knowledge, such an expressive regression in oHCM under mavacamten therapy has not been previously reported.

Learning Points from this Case:

• 
  Mavacamten therapy may lead not only to symptomatic relief and reduction of obstruction, but also to structural regression of hypertrophy in oHCM.
  
  


• 
  CMR provides precise quantification and documentation of myocardial remodeling, making it an essential tool for monitoring therapeutic response.
  
  


• 
  This case suggests that beyond functional improvement, mavacamten may promote meaningful structural reverse remodeling in selected oHCM patients.
  
  

Cine CMR images showing significant reduction of asymmetric LV hypertrophy following mavacamten treatment.