Related Experiment Videos
Left ventricular dilatation and the risk of congestive heart failure in people without myocardial infarction
R S Vasan1, M G Larson, E J Benjamin
1Framingham Heart Study, MA 01701, USA.
Insights
Increased left ventricular size predicts heart failure risk in individuals without prior heart attack. Echocardiography measurements of left ventricular dimensions can improve early detection of subclinical dysfunction.
Area of Science:
- Cardiology
- Cardiovascular Imaging
- Heart Failure Research
Background:
- Left ventricular dilatation is a known precursor to heart failure post-myocardial infarction.
- The association between left ventricular dilatation and heart failure risk in individuals without prior myocardial infarction is not well-established.
Purpose of the Study:
- To investigate the relationship between left ventricular dimensions and the risk of developing congestive heart failure in individuals without a history of myocardial infarction.
- To determine if left ventricular internal dimensions are an independent risk factor for congestive heart failure.
Main Methods:
- Utilized M-mode echocardiography to measure left ventricular end-diastolic and end-systolic internal dimensions in 4744 subjects.
- Employed sex-stratified proportional-hazards regression analysis, adjusting for traditional cardiovascular risk factors.
- Followed subjects for 11 years to ascertain the incidence of congestive heart failure.
Main Results:
- An increase of 1 standard deviation in height-indexed left ventricular end-diastolic dimension was associated with a 1.47-fold increased risk of congestive heart failure.
- Similar results were observed for left ventricular end-systolic dimension, with a hazard ratio of 1.43.
- These associations remained significant after adjusting for multiple cardiovascular risk factors.
Conclusions:
- Elevated left ventricular internal dimensions are a significant risk factor for developing congestive heart failure in both men and women, independent of prior myocardial infarction.
- Left ventricular dimension measurements enhance the predictive capability of traditional risk factors for congestive heart failure.
- These findings suggest that left ventricular dimensions may help identify individuals with subclinical left ventricular dysfunction at risk for heart failure.
Background:
Left ventricular dilatation is a well-recognized precursor of ventricular dysfunction and congestive heart failure after myocardial infarction. The effect of left ventricular dilatation on the risk of heart failure in people initially free of myocardial infarction is not known.
Methods:
We examined the relation of the left ventricular end-diastolic and end-systolic internal dimensions, as measured by M-mode echocardiography, to the risk of congestive heart failure in 4744 subjects (2083 men and 2661 women) who had not sustained a myocardial infarction and who were free of congestive heart failure. We used sex-stratified proportional-hazards regression to assess the association between base-line left ventricular internal dimensions and the subsequent risk of congestive heart failure, after adjusting for age, blood pressure, hypertension treatment, body-mass index, diabetes, valve disease, and interim myocardial infarction.
Results:
Over an 11-year follow-up period, congestive heart failure developed in 74 subjects (38 men and 36 women). The risk-factor-adjusted hazard ratio for congestive heart failure was 1.47 (95 percent confidence interval, 1.25 to 1.73) for an increment of 1 SD in the left ventricular end-diastolic dimension, indexed for height. We obtained similar results using the left ventricular end-systolic dimension (hazard ratio, 1.43; 95 percent confidence interval, 1.24 to 1.65).
Conclusions:
An increase in left ventricular internal dimension is a risk factor for congestive heart failure in men and women who have not had a myocardial infarction. Knowledge of the left ventricular dimension improves predictions of the risk of congestive heart failure made on the basis of traditional risk factors, perhaps by aiding in the identification of subjects with subclinical left ventricular dysfunction.