Related Experiment Videos
Coronary flow and left ventricular diastolic function in aortic regurgitation
G Tamborini1, P Barbier, E Doria
1Istituto di Cardiologia dell'Università degli Studi di Milano, Italy.
Insights
In aortic regurgitation, diastolic dysfunction, not ventricular mass, impacts myocardial perfusion. Valve replacement normalizes coronary flow and improves diastolic function, aiding preoperative patient evaluation.
Area of Science:
- Cardiovascular Medicine
- Echocardiography
- Cardiac Physiology
Background:
- Aortic regurgitation (AR) can impair myocardial perfusion, potentially due to abnormal coronary perfusion pressure, ventricular hypertrophy, or diastolic dysfunction.
- This study investigated the roles of ventricular hypertrophy and diastolic function in altered myocardial perfusion in AR.
Purpose of the Study:
- To determine the relationship between left ventricular diastolic function and coronary flow distribution in patients with aortic regurgitation.
- To assess the impact of aortic valve replacement on diastolic function and coronary flow.
Main Methods:
- Multiplane transesophageal echocardiography (TEE) was used to assess coronary Doppler flow velocity in the left anterior descending artery in 15 AR patients before and after valve replacement.
- Coronary flow velocity integrals and mitral inflow patterns were correlated with hemodynamic and echocardiographic indices of diastolic function.
- Patients were compared to 10 healthy controls.
Main Results:
- Aortic regurgitation was associated with reduced diastolic:systolic coronary flow velocity integral ratio and increased early:late diastolic velocity integral ratio.
- These altered coronary flow patterns correlated with impaired left ventricular diastolic function and elevated pulmonary wedge pressure.
- Valve replacement normalized diastolic function parameters and coronary flow distribution, with decreased pulmonary wedge pressure and increased coronary perfusion pressure.
Conclusions:
- Diastolic ventricular dysfunction, rather than left ventricular mass, is linked to disordered myocardial perfusion in aortic regurgitation.
- Aortic valve replacement improves diastolic function and normalizes coronary flow phasic distribution.
- Echo-Doppler parameters of diastolic dysfunction can identify patients with compromised coronary perfusion and aid preoperative assessment.
Background:
An abnormal coronary perfusion pressure is probably the major determinant of altered myocardial perfusion in aortic regurgitation; ventricular hypertrophy and diastolic function may also be involved. This study was undertaken to investigate the respective roles of these two variables.
Methods:
Using multiplane transesophageal echocardiography, we evaluated the coronary Doppler flow velocity in the proximal left anterior descending coronary artery in 15 patients with aortic regurgitation before and immediately after valve replacement. The ratios of diastolic:systolic velocity integral and early:late diastolic velocity integral were correlated against coronary perfusion pressure, pulmonary wedge pressure and Doppler echocardiographic indices of left ventricular diastolic function. Patients were compared with 10 subjects without valvular diseases.
Results:
Aortic regurgitation was associated with a reduction of the coronary diastolic:systolic velocity integral ratio and increment in the early:late diastolic velocity integral ratio. The latter correlated positively with early:late diastolic ratio of mitral flow velocity, pulmonary wedge pressure and left ventricular mass index. Soon after valve replacement, a decrease in pulmonary wedge pressure and a rise in coronary perfusion pressure were seen. Both the echo-Doppler parameters related to diastolic function and the systodiastolic distribution of coronary flow returned to normal. This indicates that diastolic dysfunction rather than left ventricular mass may be related to a disordered myocardial perfusion.
Conclusions:
In aortic regurgitation, a relationship exists between diastolic ventricular function and coronary flow phasic distribution. Valve replacement improves the former and normalizes the latter. Echo-Doppler parameters of diastolic dysfunction identify patients with worse coronary perfusion and might represent an additional criterion in the preoperative evaluation of patients with aortic regurgitation.