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Published on: August 18, 2016
The Spontaneous Coronary Slow-Flow Phenomenon: Reversal by Intracoronary Nicardipine
Hetal H Mehta, Mackenzie Morris, David L Fischman
1Cardiac Catheterization Laboratory, Thomas Jefferson University Hospital, 111 South 11th Street, Gibbon Building, Ste 6210, Philadelphia, PA 19107 USA. michael.savage@jefferson.edu.
Objective:
An under-recognized cause of chest pain, the coronary slow-flow (CSF) phenomenon is characterized by delayed coronary opacification during diagnostic angiography in the absence of epicardial coronary artery disease (CAD). Given its angiographic resemblance to no-reflow during percutaneous coronary intervention, a condition associated with microvascular spasm responsive to calcium-channel blockers, we hypothesized that spontaneous CSF may similarly be reversed by intracoronary (IC) nicardipine.
Methods:
The effect of IC nicardipine was evaluated in 30 patients. CSF was defined as spontaneously delayed flow (
Results:
The study population consisted of 22 men and 8 women (mean age, 54 ± 11 years). Clinical presentation was rest angina in 21 patients (70%). At baseline, CSF with
Conclusions:
IC nicardipine appears highly effective in reversing spontaneous CSF. These findings implicate microvascular spasm in the pathogenesis of CSF. Future studies of oral calcium-channel blockers in the long-term management of CSF are needed.
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