Abstract
Background
ECG U‐wave inversion can be classified as initial and terminal U inversion according to the phasic relationship to positive U‐wave deflection. Initial U inversion is occasionally observed in hypertensive patients while terminal U inversion frequently appears during severe myocardial ischemia.
Hypothesis
The genesis of initial U inversion may be related to pressure‐induced diastolic dysfunction.
Methods
In order to clarify the genesis of initial U‐wave inversion we studied 11 consecutive hypertensive patients with both initial U inversion and impaired left ventricular early relaxation who were evaluated using Doppler echocardiography.
Results
The U inversion disappeared during acute pressure lowering by sublingual administration of nitroglycerin. The U inversion also disappeared and relaxation improved significantly after chronic blood pressure lowering. Initial U inversion reappeared during a cold pressor test.
Conclusion
The appearance of initial U inversion was dependent on the pressure‐induced impaired left ventricular early relaxation in hypertensive patients. Copyright © 2009 Wiley Periodicals, Inc.
Keywords: U wave inversion, diastolic dysfunction, action potential duration
Full Text
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