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Relationship of contractile state to ejection performance in patients with chronic aortic valve disease
Insights
In patients with aortic valve disease, impaired contractility, not afterload mismatch, significantly contributes to left ventricular pump dysfunction. This finding highlights the need to assess contractility in managing aortic stenosis and regurgitation.
Area of Science:
- Cardiology
- Cardiovascular Physiology
- Biomedical Engineering
Background:
- Chronic aortic valve disease, including aortic stenosis and aortic regurgitation, leads to significant left ventricular (LV) remodeling.
- Understanding the primary drivers of LV pump dysfunction is crucial for effective clinical management.
Purpose of the Study:
- To differentiate the roles of afterload mismatch and impaired myocardial contractility in causing pump dysfunction in patients with chronic aortic valve disease.
Main Methods:
- Simultaneous left ventricular cineangiography and micromanometry were performed in 56 patients.
- Patients included those with severe aortic stenosis (n=21), severe aortic regurgitation (n=16), and normal controls (n=19).
- Key hemodynamic parameters and LV volumes were assessed.
Main Results:
- Patients with aortic stenosis and regurgitation exhibited increased LV mass, end-diastolic volume, and end-systolic volume compared to controls.
- Ejection fraction was depressed in both patient groups, disproportionately to the degree of afterload mismatch.
- A significant number of patients fell below the normal range for ejection fraction relative to end-systolic stress.
Conclusions:
- Impaired myocardial contractility plays a more significant role than afterload mismatch in the pump dysfunction observed in chronic aortic valve disease.
- These findings suggest that therapeutic strategies should consider addressing intrinsic myocardial function.
Abstract:
To assess the relative contributions of afterload mismatch and impaired contractility to pump dysfunction in patients with chronic aortic valve disease, simultaneous left ventricular cineangiography and micromanometry were performed in 56 patients: 21 with severe aortic stenosis, 16 with severe aortic regurgitation, and 19 normal control subjects. Left ventricular mass was increased in patients with aortic stenosis and aortic regurgitation (172 +/- 52 and 224 +/- 63 g/m2, respectively, vs 89 +/- 16 for control subjects; p less than .05) as were end-diastolic volume (101 +/- 39 and 167 +/- 44 vs 77 +/- 16 ml/m2; p less than .05) and end-systolic volume (50 +/- 40 and 84 +/- 43 vs 24 +/- 7 ml/m2; p less than .05). Although ejection fraction was depressed in both abnormal groups (0.56 +/- 0.18 for patients with aortic stenosis and 0.53 +/- 0.13 for those with aortic regurgitation vs 0.69 +/- 0.05 for control subjects; p less than .05), the decrease in ejection fraction was disproportionate to the mild degree of afterload mismatch (end ejection stress 129 +/- 17 in patients with aortic stenosis and 154 +/- 58 in those with aortic regurgitation vs 117 +/- 46 kdyn/cm2 in control subjects; p = NS) with 10 of 21 patients with aortic stenosis and 12 of 16 patients with aortic regurgitation falling below the 95% prediction limit of the linear inverse relationship between ejection fraction and end-systolic stress for controls (EF = 0.78 - 0.00074 X ESS).(ABSTRACT TRUNCATED AT 250 WORDS)