To determine whether vasoconstriction distal to the site of successful percutaneous transluminal coronary angioplasty (PTCA) is a result of altered autoregulation in a hypoperfused coronary artery, we examined the association of this distal vasoconstriction with lesion severity in 20 patients. Lesion severity was classified as moderate, severe or critical (> 1.0, 0.5-1.0, and < 0.5 mm, respectively). Quantitative coronary measurements were made at 3, 15, and 30 min after PTCA, and then after intracoronary (IC) nitroglycerin, in coronary segments distal to the dilated lesion (distal) and in a nonmanipulated vessel (control).Coronary vasoconstriction in the Distal segment after PICA correlated with lesion severity, with 14±4%, 28±2%, and 41±5% vasoconstriction (vs. IC nitroglycerin, 30 min after PTCA) in the moderate, severe and critical lesion severity subgroups, respectively (P < 0.01 for critical or severe vs. moderate). This vasoconstriction was significantly greater than that observed in the corresponding control segment for patients with severe (P <-0.01), and critical (P < 0.001) lesions.These findings suggest that hypoperfused human epicardial coronary arteries "reset" their autoregulatory responsiveness and that distal vasoconstriction after PICA is the result of this altered autoregulation. These findings have clinical implications concerning the etiology, prophylaxis and treatment of coronary spasm after PTCA and coronary bypass surgery. (J. Clin. Invest. 1990. 86:575-584.)
Injuries to the upper limb occur more often in cross-country skiing than in downhill skiing/ The nature of cross-country skiing necessitates a knowledge of emergency medical care because the cross-country skier is likely to fmd himself miles from medical assistance when an injury is sustained. Primary attention should be focused on wrist immobilization that provides adequate medical treatment and allows maximum utility.
CASE HISTORYWhile on a cross-country skiing expedition, a skier fell, with the wrist dorsiflexed, on his palm in icy snow. Pain, point Fig. 1. Spare ski tip in position required for optimal immobilization.tenderness over the distal radius, and inability to use the left arm was immediately noticed. The wrist was immobilized in a slightly palmar flexed position with the use of an emergency spare aluminum ski tip and secured with an ace bandage and adhesive tape (Figs. 1 to 3). This method of immobilization lw Fig. 2. After spare ski tip is covered with a towel to provide comfort and insulation, the ski tip is secured with an ace bandage wrapped around the ski tip, wrist, and forearm. allowed for full range of movement of the fingers, shoulder, and elbow. It was then possible for the injured skier to use his arm to hold a ski pole for support and to continue on to the ski hut 6 miles away. Later, x-ray films demonstrated an impacted fracture of the distal radius without displacement.
DISCUSSIONInjuries to the upper limb frequently occur while attempting to break a fall with an outstretched arm. Fracture of the wrist
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