The Pharmacological Basis of Therapeutics A Textbook of Pharmacology, Toxicology and Therapeutics for Physicians and Medical Students. By Prof. Louis Goodman and Prof. Alfred Gilman. Pp. xiii + 1383. (New York: The Macmillan Company, 1941.) 50s. net.

The Pharmacological Basis of Therapeutics

Much has been published in the past 20 years on the use of measurements of arterial stiffness in animal and human research studies. This summary statement was commissioned by the American Heart Association to address issues concerning the nomenclature, methodologies, utility, limitations, and gaps in knowledge in this rapidly evolving field. The following represents an executive version of the larger online-only Data Supplement and is intended to give the reader a sense of why arterial stiffness is important, how it is measured, the situations in which it has been useful, its limitations, and questions that remain to be addressed in this field. Throughout the document, pulse-wave velocity (PWV; measured in meters per second) and variations such as carotid-femoral PWV (cfPWV; measured in meters per second) are used. PWV without modification is used in the general sense of arterial stiffness. The addition of lowercase modifiers such as “cf” is used when speaking of specific segments of the arterial circulation.

The ability to measure arterial stiffness has been present for many years, but the measurement was invasive in the early times. The improvement in technologies to enable repeated, minimal-risk, reproducible measures of this aspect of circulatory physiology led to its incorporation into longitudinal cohort studies spanning a variety of clinical populations, including those at extreme cardiovascular risk (patients on dialysis), those with comorbidities such as diabetes mellitus (DM) and hypertension, healthy elders, and general populations.

In the ≈3 decades of clinical use of PWV measures in humans, we have learned much about the importance of this parameter. PWV has proven to have independent predictive utility when evaluated in conjunction with standard risk factors for death and cardiovascular disease (CVD). However, the field of arterial stiffness investigation, which has exploded over the past 20 years, has proliferated without logistical guidance for clinical and …

Recommendations for Improving and Standardizing Vascular Research on Arterial Stiffness: A Scientific Statement From the American Heart Association

Investigation of arterial stiffness, especially of the large arteries, has gathered pace in recent years with the development of readily available noninvasive assessment techniques. These include the measurement of pulse wave velocity, the use of ultrasound to relate the change in diameter or area of an artery to distending pressure, and analysis of arterial waveforms obtained by applanation tonometry. Here, we describe each of these techniques and their limitations and discuss how the measured parameters relate to established cardiovascular risk factors and clinical outcome. We also consider which techniques might be most appropriate for wider clinical application. Finally, the effects of current and future cardiovascular drugs on arterial stiffness are also discussed, as is the relationship between arterial elasticity and endothelial function.

Noninvasive Assessment of Arterial Stiffness and Risk of Atherosclerotic Events

The basal oxygen consumption of the heart is small, approximately 20 percent of that of the contracting organ. Oxygen cost of depolarization is approximately 0.5 percent of the total oxygen consumed by the normally working heart. There is a far greater oxygen cost of “pressure work” as opposed to “flow work,” and a close relation between the area beneath the left ventricular pressure curve, that is, the tension-time index, and myocardial oxygen consumption. Also, the contractile state of the heart, as reflected in the maximal velocity of isotonic shortening, is a major determinant of myocardial oxygen consumption. Thus, velocity of contraction shares the role of important determinant of myocardial oxygen consumption with developed tension and heart rate. Although the precise costs of activation and maintenance of the active state of the myocardium have not yet been clearly defined, it is likely that they are relatively low. In studies on isolated papillary muscles, oxygen consumption was found to be a function of the tension that is developed and the velocity of shortening of the unloaded muscle. Shortening against a load requires oxygen above and beyond that required for the development of tension. Almost the entire increase in myocardial oxygen consumption produced by the administration of catecholamines results from the increased contractile activity produced rather than from a direct stimulating effect of the catecholamines on myocardial metabolism. Severe valvular regurgitation does not increase myocardial consumption significantly when myocardial tension is held constant. Congestive heart failure is associated with depression of myocardial contractility, but this cannot be attributed to any reduction of high energy phosphate stores in muscles that are utilized normally. A technique for reducing myocardial oxygen requirements by stimulating the carotid sinus nerves is described and its application to the treatment of angina pectoris demonstrated. It is also shown that following coronary occlusion, interventions that increase myocardial oxygen consumption appear to increase the size of the infarction, whereas those that decrease myocardial oxygen consumption reduce the size of the infarction.

Control of myocardial oxygen consumption: physiologic and clinical considerations.

Exercise stress testing in evaluation of patients with ischemic heart disease.

These experiments trace the recent interest in the vasodilator properties of urine. This interest was triggered by the incidental observation of a potent coronary dilator influence when urine was introduced into the reservoir of the isolated supported heart preparation. A comparison of human urine with nitroglycerin then revealed that 10 ml. of urine had 2 to 3 times the dilator potency of 0.6 mg. nitroglycerin. Neither agent altered myocardial oxygen consumption or efficiency at the peak of their effect. The development of a simple, rapid and reproducible bioassay technic which would permit the comparative examination of numerous samples in the same preparation was a necessary precursor to realizing the broader objective of ascertaining whether the vasodilator substance in urine has physiologic significance for circulatory regulation. Accordingly, a re-examination was made of the limitations of the femoral arterial flow technic. The irregularity in the amplitude and contour of sequential responses to the...

Observations on the Vasodilator Properties of Urine

The influence of cardiac output, aortic pressure and heart rate on myocardial oxygen utilization.

The hemodynamic determinants of myocardial oxygen utilization were ascertained in the isolated, metabolically supported, nonfailing canine heart. The primary determinant was found to be the total t...

Hemodynamic determinants of oxygen consumption of the heart with special reference to the tension-time index.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

R. Macruz

Author Tools

Chat about Author

Papers

Observations on the Vasodilator Properties of Urine

The influence of cardiac output, aortic pressure and heart rate on myocardial oxygen utilization.

Hemodynamic determinants of oxygen consumption of the heart with special reference to the tension-time index.