Anti-ischemic effect of verapamil during an interventional recanalisation

We report on a 46-year-old male with unstable angina pectoris due to a tota l proximal occlusion of the left circumflex artery. At the side of a plaque rupture there was a thrombotic occlusion. With PTCA recanalization was pos sible, but a dissection occurred, therefore coronary stents were implanted. Besides an optimal morphological result and recurrent applications of nitr oglycerin, the baseline blood flow velocity declined from initial 16 cm/s t o 11 cm/s after PTCA down to 8.4 cm/s after stent implantation. Because pea k flow velocity remained almost unchanged, the low baseline velocity ("slow now phenomenon") did not lead to an impaired coronary flow velocity reserv e (CFVR). Only after application of 1 mg verapamil, a sustained flow veloci ty on a higher baseline level was reached (17 cm/s), at the same time typic al signs of ischemia in the ECG (ST-segment depressions) improved. Addition ally, in the non-treated LAD there was an increase in coronary blood flow v elocity from 10 cm/s up to 25 cm/s. The reduction in coronary blood flow velocity with increasing manipulations might be due to an impairment of the coronary microcirculation with increa sing a-adrenergic vasoconstriction, a distribution of vasoactive agents and peripheral microembolizations. Only after administration of verapamil, a c alcium channel blocker with non-specific anti-adrenergic effects, the slow flow was removed and ECG signs of ischemia improved. The blood flow velocity in the non-treated LAD was low at baseline and impr oved after verapamil, This phenomenon leads to the conclusion that mechanis ms with vasoconstrictive effect are present in the whole coronary system, b ut these mechanisms are less pronounced in non-treated vessels.