Related Experiment Videos
Value of vectorcardiography in predicting progress in dilated cardiomyopathy
1Second Department of Internal Medicine, Gunma University School of Medicine, Maebashi, Japan.
Insights
In dilated cardiomyopathy (DCM), specific QRS loop abnormalities in the horizontal plane, including posterior displacement, narrowness, distortion, or a figure-of-eight shape, indicate a poor prognosis for survival.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- Dilated cardiomyopathy (DCM) is a significant cause of heart failure.
- Prognostic indicators in DCM are crucial for patient management and risk stratification.
Purpose of the Study:
- To investigate the prognostic value of electrocardiographic (ECG) parameters, specifically QRS loop characteristics, in patients with DCM.
Main Methods:
- Retrospective analysis of 75 DCM patients with a mean follow-up of 39.7 months.
- Comparison of baseline clinical, hemodynamic, and ECG data between survivors and non-survivors.
- Detailed analysis of QRS and T vector magnitudes, angles, and QRS loop morphology in the horizontal plane.
Main Results:
- Mortality rate was 21.3% (16/75 patients).
- Non-survivors exhibited higher cardiothoracic ratio, elevated left ventricular end-diastolic dimensions and pressures, and lower cardiac index.
- Significant differences were observed in QRS loop morphology: posterior displacement, smaller width/length ratio, distortion, and figure-of-eight configurations were more frequent in non-survivors.
- No significant differences in maximum QRS and T vector magnitudes or maximum T angle were found.
Conclusions:
- Specific QRS loop abnormalities in the horizontal plane are associated with increased mortality in DCM.
- Posterior displacement, narrowness, distortion, or figure-of-eight configuration of the QRS loop in DCM suggests an unfavorable prognosis.
Abstract:
Sixteen of 75 patients with dilated cardiomyopathy (DCM) died during a mean follow-up period of 39.7 months. In non-survivors, the cardiothoracic ratio and the left ventricular end-diastolic dimensions were greater, the left ventricular end-diastolic pressures were more elevated, and the cardiac index was lower than in the survivors at the time of initial diagnosis. There were no significant differences between survivors and non-survivors in the magnitude of the maximum QRS and T vectors or in the maximum T angle. In the non-survivors, the maximum QRS vector was directed more posteriorly and the width/length ratio of the loop in the horizontal plane was smaller than in survivors. The QRS loop in the horizontal plane was often distorted in non-survivors or showed a bizarre figure-of-eight configuration. It appears that in DCM a marked posterior displacement of a QRS loop that is narrow and distorted or is in a bizarre figure-of-eight configuration in the horizontal plane indicates an unfavorable prognosis.