Management of recurrent ventricular tachyarrhythmias associated with Q-T prolongation

Eleven patients with acquired prolongation of the Q-Tc interval and recurrent ventricular tachyarrhythmias were studied. Five patients required 5 to 44 direct current shocks to correct prolonged ventricular tachyarrhythmias, and five were given at least two antiarrhythmic agents in an attempt to control the arrhythmias. In 4 of the 11 patients, when thioridazine, diuretic drugs and antiarrhythmic agents were withdrawn and hypokalemia or hypocalcemia corrected, ventricular tachyarrhythmias did not recur. The Q-Tc interval normalized in 2 to 3 days. Ventricular tachyarrhythmias were recurrent in the remaining seven patients, despite withdrawal of the drugs that caused the Q-Tc prolongation, attempted correction of hypokalemia when present and the administration of antiarrhythmic agents to four of the seven. All antiarrhythmic agents were then withdrawn in this group.

Immediately on the establishment of overdrive ventricular or atrioventricular sequential pacing in these patients, ventricular tachyarrhythmias were abolished. No breakthrough ventricular tachyarrhythmias occurred during temporary pacing. Temporary pacing was required for an average of 10 days and the Q-Tc interval normalized an average of 5 days from the onset of pacing. Three patients required a permanent pacemaker, one because of chronic complete heart block, one because of the sick sinus syndrome, and one because of frequent ventricular ectopic complexes complicating ischemic heart disease. All 11 patients survived their period of hospitalization.     

Esophageal tamponade in the management of acute variceal hemorrhage

Over a seven-year period, 138 patients with portal hypertension presented on 223 occasions with endoscopically proven acute variceal hemorrhage. Hemorrhage ceased spontaneously on 92 occasions (41%). On 126 occasions (57%) passage of the four-lumen modification of the Sengstaken-Blakemore tube was required, and hemorrhage was successfully controlled in 98%. Intubation was refused on five occasions (2%). Hemorrhage recurred during these 223 admissions on 47 occasions (21%); on 11 occasions a second rebleed occurred and on two occasions, a third. Tamponade was required during all of these rebleeds and arrest of hemorrhage was achieved in 87%. Hemorrhage in patients with poorer modified Child's grade was less likely to cease with intubation. The overall rate of control in the 186 episodes of hemorrhage requiring tamponade was 94%. There were 28 complications attributed to the use of tamponade in 186 episodes of hemorrhage (15%). On 12 occasions these complications proved fatal (6.4%). In four further patients failure of tamponade to control hemorrhage was fatal.     

Endothelial dysfunction in streptozotocin-diabetic rats is not reversed by dietary probucol or simvastatin supplementation

Summary Oxidative stress and dyslipidaemia are key features of diabetes mellitus and may be involved in mediating the vascular endothelial dysfunction associated with this disease. The aim of this study was to examine the effect of dietary lipid-lowering and antioxidant agents on vascular endothelial function and oxidative stress. Diabetic male Sprague-Dawley rats (i. v. streptozotocin, 45 mg/kg) were fed for 4 weeks on a standard diet or on a diet supplemented with either the lipid-lowering antioxidant probucol (1 % w/w in diet) or the 3-hydroxy 3-methylglutaryl coenzyme-A (HMG-CoA) reductase inhibitor simvastatin (0.01 % w/w in diet). Responses to noradrenaline, acetylcholine, and sodium nitroprusside were assessed in small mesenteric arteries (mean internal diameter 300 ± 5 μm, n = 80) mounted on a small vessel myograph. Plasma concentrations of total cholesterol and triglycerides were significantly raised in standard-fed diabetic rats and significantly reduced in probucol and simvastatin-fed diabetic rats. 8-epi-prostaglandin (PG)F₂α, an indicator of oxidative stress, was raised in liver and aorta from diabetic rats compared to controls. Probucol supplementation reduced 8-epi-PGF₂α in aorta and liver of diabetic rats but increased 8-epi-PGF₂α content in plasma and aorta from control animals. The abnormal relaxation to acetylcholine in arteries from the diabetic rats (pEC₅₀ diabetic 6.763 ± 0.172 vs control 7.541 ± 0.175; p < 0.05) was not improved by probucol or simvastatin. These data, therefore, do not support a role for oxidative stress or dyslipidaemia in mediating the impaired ACh-induced endothelium-dependent relaxation of small mesenteric arteries from the streptozotocin-diabetic rat. [Diabetologia (1998) 41: 157–164] Received: 4 August 1997 and in revised form: 29 September 1997     

The renin-angiotensin-aldosterone system in fulminant hepatic failure

The relationship of the renin-angiotensin-aldosterone system to blood pressure and sodium homeostasis and to renal function was investigated serially in 12 patients with fulminant hepatic failure. The plasma concentrations of renin, angiotensin II, and aldosterone were, in most instances, markedly increased. Systolic blood pressure, which was often very low, showed a significant inverse relationship to the plasma renin concentration, suggesting that the marked stimulation of the system is a homeostatic response to hypotension. However, the plasma renin substrate concentration was markedly decreased, and the conversion of angiotensin II to inactive peptides increased, both of which may have severely limited the full 'expression' of the stimulated system. Renin and angiotensin II levels were both related to creatinine clearance, which was often reduced, but it is not clear as to which was cause and which effect. No relationship between the plasma aldosterone concentration and renal sodium excretion could be detected.     

Discriminant analysis of data in ulcer and nonulcer populations

The purpose of this study was to assess whether consideration of age and body weight measurements improved discrimination between normal subjects and duodenal ulcer subjects using the maximal acid output test. Seventy-seven male volunteers were the normal group, and 155 patients with surgically proven duodenal ulcers were the ulcer group. We found that the ratio of maximal acid output to actual weight gave the best discrimination between the two groups. Using this ratio, there were 45 hypersecretors in the ulcer group, and only 1 false-positive among the normal subjects. A graphic method is described which employs the ratio of acid to weight and can correctly classify two-thirds of the ulcer group. The disadvantage of this method, however, is that one-third of the control group in our series were misclassified as hypersecretors; therefore, the clinician must consider history and barium meal findings as well as this evaluation of the subject.Deceased.     

Percutaneous treatment of a popliteal bifurcation—The value of coronary devices and strategies

In this case report, we describe the use of coronary techniques and devices in the treatment of a complex popliteal artery bifurcation. In particular, we demonstrate that the Venture? wire control catheter is a useful tool not only in coronary lesions but also in wiring angulated peripheral lesions. © 2008 Wiley‐Liss, Inc.