Author + information
- Received January 31, 1992
- Revision received April 20, 1992
- Accepted April 22, 1992
- Published online September 1, 1992.
- Robert J. Siegel, MD, FACCa,∗,
- Peter Gaines, MD∗,
- Anne Procter, MD∗,
- Tim A. Fischell, MD, FACC† and
- David C. Cumberland, MD∗
- ↵∗Address for correspondence: Robert J. Siegel, MD, Division of Cardiology, Room 5314, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, California 90048-0750.
Objectives. This study was designed to describe the clinical effects of ultrasound energy on guide-wire-induced arterial vasoconstriction.
Background. We have previously shown that ultrasound energy (20 kHz) delivered by a wire probe produces dose-dependent, endothelium-independent smooth muscle relaxation capable or reversing both receptor-mediated and voltage-dependent vasoconstriction in vitro.
Methods. A high intensity, low frequency ultrasound catheter system was used to recanalize total occlusions in the superficial femoral arteries of two patients. After recanalization, the proximal residual stenoses were each < 15%. However, distal arterial vasospasm was found angiographically in a popliteal artery of one patient and in an anterior tibial artery of another. Subsequently, the ultrasound catheter probe was advanced to the sites of arterial vasospasm (diffuse in one, focal in one).
Results. After 30 and 90 s, respectively, of exposure to ultrasound energy with a frequency of 19.5 kHz, peak tip amplitude of 111 μm and power output at the transducer of 25 W, the vasospasm resolved in each arterial segment.
Conclusions. Our findings are the first reported clinical cases documenting that catheter-delivered low frequency, high intensity ultrasound induces arterial vasodilation at the site of vasoconstriction. These biologic effects appear to be relatively unique for an angioplasty device and may have potential clinical importance.
☆ This study was supported in part by grants from Baxter-Edwards Health Care Corporation, Irvine, California and the Lee F. Siegel, MD Memorial Fund, Los Angeles.
- Received January 31, 1992.
- Revision received April 20, 1992.
- Accepted April 22, 1992.