Electromechanical relationship in hypertrophic cardiomyopathy

Xiaoping Lin1, Hsin-Yueh Liang, Aurelio Pinheiro

  • 1Division of Cardiology, Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 871, Baltimore, MD 21201, USA.

Insights

Electrocardiography (EKG) repolarization abnormalities and left ventricular hypertrophy (LVH) indicate impaired heart mechanics in hypertrophic cardiomyopathy (HCM). These EKG findings correlate with reduced systolic and diastolic function detected by echocardiography.

Area of Science:

  • Cardiology
  • Biomedical Engineering
  • Medical Imaging

Background:

  • Hypertrophic cardiomyopathy (HCM) is a genetic heart disease characterized by abnormal thickening of the heart muscle.
  • Electrocardiography (EKG) and echocardiography are standard diagnostic tools for HCM.
  • Repolarization abnormalities on EKG and deformation abnormalities on echocardiography are common findings in HCM, but their relationship is not fully understood.

Purpose of the Study:

  • To investigate the association between repolarization abnormalities on EKG and deformation abnormalities assessed by echocardiography in patients with HCM.
  • To determine if specific EKG findings, such as left ventricular hypertrophy (LVH) and QTc prolongation, correlate with impaired cardiac mechanics.

Main Methods:

  • Analysis of baseline EKGs and echocardiographic deformation parameters in 128 patients diagnosed with HCM.
  • Comparison of cardiac mechanics between patients with and without EKG abnormalities, including LVH, QTc prolongation, and repolarization patterns (ST depression/T-wave inversion).

Main Results:

  • Patients with LVH or repolarization abnormalities on EKG exhibited increased septal thickness compared to those with normal EKGs.
  • EKG evidence of LVH or QTc prolongation was associated with significantly lower systolic velocity, strain, strain rate, and diastolic velocities.
  • Specific repolarization patterns like strain pattern or ST depression/T-wave inversion correlated with reduced systolic and diastolic function.

Conclusions:

  • Left ventricular hypertrophy and repolarization abnormalities detected by surface EKG serve as important indicators of compromised systolic and diastolic mechanics in HCM patients.
  • EKG findings can predict impaired cardiac function, aiding in risk stratification and management of HCM.

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