lipidaemic agents (usually a statin). If coronary arterial spasm seems a likely aetiological agent in such a patient, I also prescribe a vasodilator, i.e. a calcium channel blocker, an ACE inhibitor, or an angiotensin receptor blocker. These patients represent a very interesting subset of individuals with myocardial infarction. I am convinced that they will continue to be the subject of clinica...

Background Left bundle branch block (LBBB) is a condition associated with increased mortality and poor prognosis, depending on the underlying etiology. Identification of the etiology and appropriate risk stratification of patients with LBBB is a challenge, despite the availability of various testing modalities. Nuclear exercise stress testing can show artificial perfusion defects in the interve...

The ratio of pulmonary to systemic vascular resistance (Rp/Rs) largely determines the amount of left-to-right shunting and pulmonary to systemic flow rat (Qp/Qs) in the presence of a large isolated ventricular septal defect. The possibility that pharmacologic reduction of systemic vascular resistance with alpha-adrenergic receptor blockade or beta-adrenergic receptor stimulation would increase ...

For over 20 yrs it has been recognized that the vasodilator responses to many agents are mediated by the release of a vasodilator substance from endothelial cells [1]. The identity of endothelium-derived relaxant factor (EDRF) remained elusive, largely because of its short half-life, until 1987 when PALMER and eo-workers [2] were able to show that EDRF was likely to be nitric oxide (NO). Many w...

Propranolol is a nonselective beta-adrenergic receptor blocking agent possessing no other autonomic nervous system activity. It specifically competes with beta-adrenergic receptor agonist agents for available receptor sites. When access to beta-receptor sites is blocked by propranolol, the chronotropic, inotropic, and vasodilator responses to beta-adrenergic stimulation are decreased proportion...

Drugs that are currently used for therapeutic purposes can also be used in diagnostic tests. This paper will review the use of such pharmacological interventions in cardiac assessment in Nuclear Medicine. To fully comprehend the effect of these drugs, a small review of diagnostic nuclear medicine as currently used to assess cardiac perfusion is included. This will allow pharmacists to understan...

• Microelectrode studies, which are difficult to perform on mammalian blood vessels, have provided a few records of action potentials from mammalian arteries' -' and veins. These studies indicated that epinephrine or sympathetic nerves could, at least on some occasions, induce action potentials in the smooth muscle cells. Two experiments had suggested that such electrical changes might play no ...

Possible interactions between three calcium entry blocking agents (nifedipine, verapamil and bepridil) and the non-depolarizing neuromuscular blocking agent, vecuronium bromide, were investigated in chloralose-anaesthetized cats. In i.v. doses which caused decreases in arterial pressure, the calcium entry blockers did not affect indirectly-elicited twitches of tibialis muscle, but did potentiat...

Antihypertensive agents have been associated with adverse reactions that, if unrecognized by health practitioners, may have devastating consequences. The pattern of hepatotoxicity observed during therapy with the vasodilator hydralazine is highly variable, often making its diagnosis difficult. Serious hepatic injury induced by the alpha- and beta-adrenergic receptor antagonist labetalol has onl...