The Effect of Persantin on Intercoronary Collateral Circulation and Survival During Gradual Experimental Coronary Occlusion: A Preliminary Report

Twenty-five dogs were exposed to gradual coronary occlusion by placing Ameroid constrictors around the origins of the left circumflex and anterior descending coronary arteries. Previous experiments have demonstrated that these constrictors absorb water and, over a period of three weeks, narrow the cross-sectional area of the two arteries to 50% or less, and consequently cause the death of 80% of the experimental animals. Twelve of the 25 animals were fed 50 mg. of Persantin three times a day by mouth commencing one day before the operative procedure. Determinations of the concentration of the drug in the blood revealed a level consistent with that obtained in humans after the administration of therapeutic doses. Eleven of the 13 control animals died in the three-month experimental period while only six of the 12 treated animals expired. Injections of Schlesinger mass in all animals dying or killed following the experimental period demonstrated that Persantin significantly accelerated the development of intercoronary anastomoses in the treated group, and in the surviving animals produced a rich anastomotic network much in excess of that seen in the surviving animals in the control series that were exposed to hypoxia alone. On the basis of these experimental findings, it is suggested that Persantin may favourably alter the prognosis of many patients with coronary artery disease.     

裁剪带蒂回肠移植中血管蒂延长的实验研究

目的:建立结扎不同回肠血管分支的动物实验模型,即时及术后动态观察移植肠段存活和通畅情况,从动物实验的角度探讨回肠血供特征及血管蒂延长方法,为临床外科手术改善提供实验依据。方法:家兔12只,体重量2～2.5kg。麻醉、固定、备皮、切口选取等均相同,将家兔分别分为6组,根据回肠血管分支结扎处理不同,分为A、B、C、D、E、F组,每组2只。建立饲养观察表格,并于术后即刻及7天分别取末端回肠组织行HE染色,读取病理切片结果。结果:A、D实验组结果分别与C、F对照组结果不同,B、E实验组结果分别与C、F对照组结果无明显差别。结论:带一支血管蒂的移植肠段结扎远端一支二级血管肠段可存活;带二支血管蒂的移植肠段结扎远端一支一级血管肠段可存活。同时,结扎带一支血管蒂的移植肠段的一级血管不可保障肠段存活。     

The Pathology of Coronary Heart Disease

The distribution of coronary atherosclerosis in patients with ischemic heart disease is extensive, and involves at least two major coronary arteries. Thrombosis, occlusion by atheromatous debris and, infrequently, internal hemorrhage may produce final closure of the coronary artery. The anatomy of the coronary vessels, localization of occlusion, recanalization, the extent of intercoronary anastomoses and the physiological demands of the myocardium all affect the ultimate clinical expression of the basic occlusive process.     

The Geographic Pathology of Coronary Atherosclerosis

The purpose of these studies was to find large groups with significantly less coronary atherosclerosis than New Yorkers and to investigate the possible reasons for these differences. Direct comparison of hearts and measurements of coronary artery wall thickness, autopsy series, and clinical diagnoses of outpatients and hospital admissions revealed that the amount of coronary atherosclerosis and the number of myocardial infarcts is significantly less in East and West Africans compared to New Yorkers matched for age and sex. The factors producing these differences are apparently operative in childhood. East Africans were found to have a shorter blood clot-lysis time, fewer venous (and arterial) thromboemboli and lower serum lipid levels, with a lower relative percentage of serum linoleates, than age-matched New Yorkers.     

Studies on Solute Transfer in the Vascular Endothelium

Barium chromate, Prussian blue, and cobalt-cobalticyanide can be precipitated in vivo in the endothelium of mesenteric vessels by injection of the appropriate anions into the blood stream, and topical application of the precipitating cations to the exposed mesenteries of mice and frogs. Precipitation in the endothelium occurs in the form of a diffuse fine punctate precipitate, and also as continuous lines demarcating endothelial cell outlines. A striking feature is the frequent occurrence of this type of precipitation in a tapering zone downstream from mural thrombi in the veins.     

Flow Regulation in Coronary Vascular Tree: A Model Study

Background

Coronary blood flow can always be matched to the metabolic demand of the myocardium due to the regulation of vasoactive segments. Myocardial compressive forces play an important role in determining coronary blood flow but its impact on flow regulation is still unknown. The purpose of this study was to develop a coronary specified flow regulation model, which can integrate myocardial compressive forces and other identified regulation factors, to further investigate the coronary blood flow regulation behavior.

Method

A theoretical coronary flow regulation model including the myogenic, shear-dependent and metabolic responses was developed. Myocardial compressive forces were included in the modified wall tension model. Shear-dependent response was estimated by using the experimental data from coronary circulation. Capillary density and basal oxygen consumption were specified to corresponding to those in coronary circulation. Zero flow pressure was also modeled by using a simplified capillary model.

Result

Pressure-flow relations predicted by the proposed model are consistent with previous experimental data. The predicted diameter changes in small arteries are in good agreement with experiment observations in adenosine infusion and inhibition of NO synthesis conditions. Results demonstrate that the myocardial compressive forces acting on the vessel wall would extend the auto-regulatory range by decreasing the myogenic tone at the given perfusion pressure.

Conclusions

Myocardial compressive forces had great impact on coronary auto-regulation effect. The proposed model was proved to be consistent with experiment observations and can be employed to investigate the coronary blood flow regulation effect in physiological and pathophysiological conditions.     

Vascular Occlusion Training for Inclusion Body Myositis: A Novel Therapeutic Approach

Inclusion body myositis (IBM) is a rare idiopathic inflammatory myopathy. It is known to produces remarkable muscle weakness and to greatly compromise function and quality of life. Moreover, clinical practice suggests that, unlike other inflammatory myopathies, the majority of IBM patients are not responsive to treatment with immunosuppressive or immunomodulatory drugs to counteract disease progression¹. Additionally, conventional resistance training programs have been proven ineffective in restoring muscle function and muscle mass in these patients^2,3. Nevertheless, we have recently observed that restricting muscle blood flow using tourniquet cuffs in association with moderate intensity resistance training in an IBM patient produced a significant gain in muscle mass and function, along with substantial benefits in quality of life⁴. Thus, a new non-pharmacological approach for IBM patients has been proposed. Herein, we describe the details of a proposed protocol for vascular occlusion associated with a resistance training program for this population.Download video file.^{(106M, mp4)}     

Primary Macroglobulinemia: Death due to Mesenteric Vascular Occlusion with Gas in the Portal Venous System

Clinical features presented by a patient with primary macroglobulinemia over a four-year period included cachexia, weight loss, bleeding tendency, anemia, lymphadenopathy, hepatosplenomegaly and recurrent pulmonary bacterial infections. Immunoelectrophoresis demonstrated the presence of a β₂ macroglobulin which, on ultracentrifugation, was found to have a sedimentation constant of 14.9 S₂₀, w; this macroglobulin constituted over 40% of the total serum protein. Postmortem findings included the typical “naked” lymphocyte infiltration of the reticuloendothelial system, with septic embolization from a terminal Gram-negative bacteremia, associated with a mesenteric vascular occlusion. A feature of particular interest was the antemortem appearance of gas in the portal venous system, shown on two abdominal scout radiographs taken one and two hours before death. The diagnostic significance of this rare radiologic sign is discussed.