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[Dynamics of cardiac output in patients with hypertrophic obstructive cardiomyopathy]
Insights
Systolic flow time in hypertrophic obstructive cardiomyopathy (HOCM) varies within the ascending aorta. In HOCM patients, posterior aortic wall flow time is significantly reduced compared to normals.
Area of Science:
- Cardiovascular Physiology
- Echocardiography
- Hemodynamics
Context:
- Hypertrophic obstructive cardiomyopathy (HOCM) is a complex cardiac condition.
- Understanding aortic flow dynamics is crucial for HOCM assessment.
- Doppler 2D-echocardiography provides insights into blood flow patterns.
Purpose:
- To characterize the duration of aortic flow velocity waveforms in HOCM.
- To investigate the spatial variation of aortic flow dynamics in HOCM patients.
- To compare flow velocity waveform duration between HOCM patients and healthy controls.
Summary:
- Aortic flow dynamics were assessed in 10 normal subjects and 11 HOCM patients using 16-gated Doppler 2D-echocardiography.
- Relative ejection time (% SEP) was measured at anterior, posterior, and central aortic walls.
- In HOCM, % SEP was significantly reduced at the posterior aortic wall (68 ± 5%) compared to other locations and normals.
Impact:
- Findings suggest that systolic flow time in HOCM varies spatially within the ascending aorta.
- Abbreviated flow time at the posterior aortic wall in HOCM may have diagnostic or prognostic implications.
- This study highlights the importance of considering spatial variations in Doppler-derived flow parameters in HOCM.
Abstract:
To characterise the duration of aortic flow velocity waveforms in hypertrophic obstructive cardiomyopathy (HOCM) the dynamics of aortic flow were investigated in 10 normals and 11 patients with hypertrophic obstructive cardiomyopathy performing 16-gated Doppler 2D-echocardiography of the ascending aorta. 16 flow velocities were recorded along the Doppler beam axis between the anterior and posterior aortic walls, and averaged over 8 beats. Flow times were derived from the flow curves and normalised by the ejection period as determined from the carotid pulse tracing. Thus, relative ejection time (% SEP) was calculated at the anterior (gate 4) and the posterior aortic wall (gate 13) as well as at the axis of the vessel (gate 9). In normals % SEP was 92 +/- 3% in gate 4, 95 +/- 4% in gate 9 and 93 +/- 3% in gate 13 (NS). In patients with HOCM % SEP was 92 +/- 5% in gate 4 and 83 +/- 4% (NS) in gate 9. At the posterior aortic wall (gate 13) % SEP amounted to 68 +/- 5% and was significantly lower than in gate 9 (P less than 0.05) and in gate 4 (P less than 0.001) respectively. It is concluded that in contrast to normals systolic flow time in hypertrophic obstructive cardiomyopathy varies along the sound beam in the ascending aorta. Flow time recorded at the posterior aortic wall is most abbreviated.