Coronary steal

Miscellaneous Hepatotoxicity stored in 0.01% thymol light sensitive Coronary steal maintains renal blood flow Hepatotoxic avoid in renal impairment Renal toxicity Oxidizes cobalt ion in vitamin B12... 

Sevoflurane, in common with all volatile agents, reduces cardiac output and systemic blood pressure. It does so mainly through a reduction in peripheral vascular resistance. Although it is a systemic vasodilator it does not appear to produce significant dilatation of small coronary vessels and there is no possibility of coronary steal as hypothesised for isoflurane. A small increase in heart rate may be observed. This is less pronounced than with isoflurane and desflurane and is almost certainly the result of reflex activity secondary to the reduction in peripheral vascular resistance. Sevoflurane is associated with a stable heart rhythm and does not predispose the heart to sensitisation by catecholamines. In children, halothane causes a greater decrease in heart rate, myocardial contractility and cardiac output than sevoflurane at all concentrations. For these reasons sevoflurane is advocated for use in outpatient dental anaesthesia, especially in children. 

The effects of desflurane are similar to those of isoflurane although possibly less pronounced at equi-MAC concentrations. There is a dose-dependent reduction in myocardial contractility, cardiac output, arterial blood pressure, and systemic vascular resistance. The [xssibility of coronary steal is of negligible clinical significance. 

Coronary steal with worsening of myocardial ischemia related to vasodilatation has been reported in a patient taking nicotinic acid (17), which should therefore perhaps be withheld in patients with unstable angina. 

Sildenafil was the first oral treatment for ED and is the most extensively evaluated (35). Overall success rates in patients with cardiovascular disease of 80% or greater have been recorded with no evidence of tolerance, Patients with diabetes with or without additional risk factors, with their more complex, and extensive pathophysiology, have an average success rate of 60%. In randomized trials to date, open-label or outpatient monitoring studies the use of sildenafil is not associated with any excess risk of myocardial infarction, stroke, or mortality (38-40), In patients with stable angina pectoris there is no evidence of an ischemic effect due to coronary steal, and in one large, double-blind, placebo-controlled, exercise study sildenafil 100 mg increased exercise time and diminished ischemia (41), A study of the hemodynamic effects in men with severe CAD identified no adverse cardiovascular effects and a potentially beneficial effect on coronary blood flow reserve (42), Studies in patients with and without diabetes have demonstrated improved endothelial function acutely and after long-term oral dose administration, which may have implications beyond... 

Despite some coronary vasodilatation in dogs, there is no evidence of coronary steal in man. Desflurane may benefit elderly patients by allowing more rapid recovery from anesthesia (8). 

Halothane, isoflurane, and sevoflurane are potent coronary vasodilators, able to produce some degree of coronary steal in ischemic regions. Despite this, halothane may preferentially dilate large coronary arteries and/or interfere with platelet aggregation. If these experimental effects are confirmed, halothane may be the anesthetic of choice in the non-failing ischemic heart (3). 

The most controversial adverse effect of isoflurane is its potential to cause coronary steal in patients with critical... 

Ischemic chest pain is an infrequent but well-documented adverse effect of initiating therapy with nifedipine (5). Its mechanism is unclear, but it may arise from reduced overall coronary blood flow or coronary steal (6). 

Alternatively, bradycardia can accompany hypotension or syncope (25-27), presumably due to a vagal effect (it is responsive to atropine) complete heart block has also been reported (28). Occasionally, similar events occur in patients without ischemic heart disease (29), suggesting a mechanism similar to vasovagal syncope or coronary artery spasm (30,31) rather than coronary steal. 

Nitrates can precipitate myocardial infarction in susceptible patients (32), and occasionally worsen myocardial infarction, producing asystole (33) or ventricular fibrillation (34,35), possibly due to coronary steal or reperfusion of ischemic myocardium. 

At perfusion pressures below 60 mm Hg, since the coronary arteries are maximally dilated and the buffering effect of autoregulation has reached its capacity, further reduction in coronary blood flow will decrease perfusion pressure and tissue oxygenation. It is thought that autoregulation works more efficiently in the epicardial layers than in the subendocardial layers, and this may contribute to coronary steal. 

Aggrenox) (-1- aspirin 50 mg) aggregation (complete MOA unknown) hypotension headache dizziness ("coronary steal syndrome") not specified in report... 

Drugs that potently dilate arterioles can cause a phenomenon known as coronary steal, whereby the increase in flow caused by the arteriolar dilation draws blood from unobstructed vessels and increases flow to areas already well perfused. This steals blood preferentially from vessels which may be obstructed (have lesser flow), and decreases perfusion in those areas which may already be ischemic. 

Regadenoson has an improved side effect profile in comparison to adenosine and dipyridamole. However, it may also precipitate myocardial infarction. This adverse effect is secondary to coronary steal phenomenon induced by regadenoson administration. Most likely, in this mechanism A2A vasodilatation causes intercoronary and transmxual steal phenomenon which in the presence of a preexisting stenotic lesion results in myocardial infarction [6]. 

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