Cardiovascular phenomena

Hepatic reperfusion injury is not a phenomenon connected solely to liver transplantation but also to situations of prolonged hypoperfusion of the host s own liver. Examples of this occurrence are hypovolemic shock and acute cardiovascular injur) (heart attack). As a result of such cessation and then reintroduction of blood flow, the liver is damaged such that centrilobular necrosis occurs and elevated levels of liver enzymes in the serum can be detected. Particularly because of the involvement of other organs, the interpretation of the role of free radicals in ischaemic hepatitis from this clinical data is very difficult. The involvement of free radicals in the overall phenomenon of hypovolemic shock has been discussed recently by Redl et al. (1993). More specifically. Poll (1993) has reported preliminary data on markers of free-radical production during ischaemic hepatitis. These markers mostly concerned indices of lipid peroxidation in the serum and also in the erythrocytes of affected subjects, and a correlation was seen with the extent of liver injury. The mechanisms of free-radical damage in this model will be difficult to determine in the clinical setting, but the similarity to the situation with transplanted liver surest that the above discussion of the role of XO activation, Kupffer cell activation and induction of an acute inflammatory response would be also relevant here. It will be important to establish whether oxidative stress is important in the pathogenesis of ischaemic hepatitis and in the problems of liver transplantation discussed above, since it would surest that antioxidant therapy could be of real benefit. 

Several recent discoveries have shifted the paradigm for myocardial regeneration and have fueled enthusiasm for a new frontier in the treatment of cardiovascular disease with stem cells. Fundamental to this emerging field is the cumulative evidence that adult bone marrow stem cells can differentiate into a wide variety of cell types, including cardiac myocytes and ECs. This phenomenon has been termed stem... 

Before opposing two interpretations of a phenomenon that is not yet completely demonstrated (cardiovascular and renal benefits independent of a fall in blood pressure), it is worthwhile to reemphasize that the clinical measurement of blood pressure by physicians or nurses is an insensitive and imprecise method for investigating the human organism s hemodynamics. Failure to detect a fall in blood pressure by this method does not eliminate a hemodynamic effect. The cellular actions of angiotensin II (290) and its hemodynamic effects are so closely linked that attributing cardiovascular changes to one at the expense of the other is probably an intellectual exercise more than a realistic approach. 

Cardiovascular adverse effects of interferon beta include isolated reports of severe Raynaud s phenomenon (SEDA-22, 374) and acute myocarditis (SEDA-21, 374). 

It is unclear whether topiramate played any role in rare cardiovascular events. These included symptoms of Raynaud s phenomenon in three patients, and third-degree atrioventricular block requiring emergency cardiac pacemaker implantation in one patient with preexisting right bundle branch block (SEDA-21, 76). 

Verapamil, proprietaiy name Calan, is a calcium channel blocker that is effective in the treatment of various cardiovascular disorders, including angina (classical and variant), arrhythmias (paroxysmal supraventricular tachycardia), atrial flutter, atrial fibrillation, hypertrophic cardiomyopathy (idiopathic hypertrophic subaortic stenosis), hypertension, congestive heart failure, and Raynaud s phenomenon, along with the preservation of ischemic myocardium and the treatment of migraine headaches. 

At the moment I am more interested in the principle of this resetting phenomenon than the details of its mechanisms. It illustrates beautifully the great importance of looking at diseases such as arterial hypertension and atherosclerosis as diseases of regulation/ The term arterial hypertension" is not a good one to describe the cardiovascular disease in which not only is the pressure abnormally elevated but there is accompanying vascular disease. It is obvious that it is the vascular disease which kills the patient. 

In patients with BPH, the most common adverse effects for ai-adrenergic antagonists are related to vasodilation, including dizziness, orthostatic hypotension, headache, and tachycardia, which occurred during the first 2 weeks of treatment (46). Therefore, a dose titration usually is required, especially in patients older than 60 years. These cardiovascular side effects are attributed to a nonselective blockade of ai-adrenoceptors present in vascular smooth muscle in addition to the required blockade of ai-adrenoceptors in prostate. No first-dose effect and fewer vasodilatory adverse events have been reported with the sustained-release formulations, which occur more frequently with the immediate-release formulation At higher doses, orthostatic hypotension occurs more frequently. The first-dose phenomenon of orthostatic hypotension and syncope has been reported occasionally in elderly patients and in those concurrently receiving calcium antagonists, diuretics, and p-blockers. 

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