Key result
Severe AS linked to impaired diastolic untwisting velocity despite higher maximal systolic torsion.
Why the study?
Diastolic dysfunction with delayed relaxation occurs in patients with severe pressure overload hypertrophy, motivating an evaluation of the time course of left ventricular rotational motion in patients with aortic valve stenosis using myocardial tagging.
How does severe aortic valve stenosis affect the rotational motion and relaxation of the left ventricle compared to controls?
Case-Control (n=25)
How does severe aortic valve stenosis affect the rotational motion and relaxation of the left ventricle compared to controls?
Answers are grounded in this paper and cite their sources.
Severe aortic valve stenosis is associated with altered left ventricular rotational mechanics, including increased apical rotation and delayed diastolic untwisting, which may contribute to diastolic dysfunction.
BACKGROUND: Diastolic dysfunction with delayed relaxation and abnormal passive elastic properties has been described in patients with severe pressure overload hypertrophy. The purpose of this study was to evaluate the time course of rotational motion of the left ventricle in patients with aortic valve stenosis using myocardial tagging. METHODS: Myocardial tagging is a non-invasive method based on magnetic resonance which makes it possible to label ('tag') specific myocardial regions. From the motion of the tag's cardiac rotation, radial displacement and translational motion can be determined. In 12 controls and 13 patients with severe aortic valve stenosis systolic and diastolic wall motion was assessed in an apical and basal short axis plane. RESULTS: The normal left ventricle performs a systolic wringing motion around the ventricular long axis with clockwise rotation at the base (-4.4+/-1.6 degrees) and counter-clockwise rotation at the apex (+6.8+/-2.5 degrees) when viewed from the apex. During early diastole an untwisting motion can be observed which precedes diastolic filling. In patients with aortic valve stenosis systolic rotation is reduced at the base (-2.4+/-2.0 degrees; P<0.01) but increased at the apex (+12.0+/-6.0 degrees; P<0.05). Diastolic untwisting is delayed and prolonged with a decrease in normalized rotation velocity (-6.9+/-1.1 s(-1)) when compared to controls (-10.7+/-2.2 s(-1); P<0.001). Maximal systolic torsion is 8.0+/-2.1 degrees in controls and 14.1+/-6.4 degrees (P<0.01) in patients with aortic valve stenosis. CONCLUSIONS: Left ventricular pressure overload hypertrophy is associated with a reduction in basal and an increase in apical rotation resulting in increased torsion of the ventricle. Diastolic untwisting is delayed and prolonged. This may explain the occurrence of diastolic dysfunction in patients with severe pressure overload hypertrophy.
No takes yet. Share an insight, caveat, or question.
Eike Nagel (2000) conducted a case-control in Severe aortic valve stenosis (n=25). Severe aortic valve stenosis vs. Healthy controls was evaluated on Normalized diastolic untwisting rotation velocity (p=<0.001). Severe aortic valve stenosis increased maximal systolic torsion and reduced diastolic untwisting velocity compared to controls.
Synapse has enriched 10 related papers. Consider them for comparative context: