John A. Murray

ACC/AHA guidelines for coronary angiography: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Coronary Angiography) developed in collaboration with the Society for Cardiac Angiography and Interventions

Preamble…1757 I. Introduction…1758 II. General Considerations Regarding Coronary Angiography…1759 A. Definitions…1759 B. Purpose…1759 C. Morbidity and Mortality…1760 D. Relative Contraindications…1760 E. Utilization…1761 F. Costs…1763 G. Cost-Effectiveness…1764

Variability in the analysis of coronary arteriograms.

Variability in coronary arteriogram readings was studied by having cine films from ten patients read by eleven readers. Three of the eleven subsequently met as an expert panel to provide a joint evaluation which could serve as a standard. Considerable variability was found between individual readers and between readers and the panel. The average standard deviation for estimation of any segmental stenosis by any single reader was 18%. Disagreement about the number of major vessels with a 70% stenosis occurred 31% of the time. Discrepancies were most likely to occur in analyzing distal arterial segments, in reading nonopacified segments, and during analysis of films showing more severe disease or having poorer technical quality. Recent experience in reading arteriograms seemed to be the most important characteristic in determining the accuracy of a reader. A protocol for the use of three readers is suggested.

ACC/AHA Guidelines for Coronary Angiography. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Coronary Angiography)

Preamble…1757 I. Introduction…1758 II. General Considerations Regarding Coronary Angiography…1759 A. Definitions…1759 B. Purpose…1759 C. Morbidity and Mortality…1760 D. Relative Contraindications…1760 E. Utilization…1761 F. Costs…1763 G. Cost-Effectiveness…1764

ACC/AHA guidelines for coronary angiography

Preamble…1757 I. Introduction…1758 II. General Considerations Regarding Coronary Angiography…1759 A. Definitions…1759 B. Purpose…1759 C. Morbidity and Mortality…1760 D. Relative Contraindications…1760 E. Utilization…1761 F. Costs…1763 G. Cost-Effectiveness…1764

ACC/AHA Guidelines for Coronary Angiography: Executive Summary and Recommendations A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Coronary Angiography) Developed in collaboration with the Society for Cardiac Angiography and Interventions

This document revises and updates the original “Guidelines for Coronary Angiography,” published in 1987. This executive summary and recommendations appears in the May 4, 1999, issue of Circulation . The guidelines in their entirety, including the American College of Cardiology/American Heart Association (ACC/AHA) class I, II, and III recommendations, are published in the May 1999 issue of the Journal of the American College of Cardiology . Reprints of both the full text and executive summary and recommendations are available from both organizations. The frequent and still growing use of coronary angiography, its relatively high costs, its inherent risks, and the ongoing evolution of its indications provide the reasons for this revision. The committee appointed to develop this document included private practitioners and academicians who were selected to represent both experts in coronary angiography and senior clinician consultants. Representatives from the family practice and internal medicine professions were also included on the committee. In addition to reviewing the original document, the committee conducted a search of the literature for the 10 years preceding development of these guidelines. Evidence was compiled and ranked by the committee. Whereas randomized trials are often available for reference in the development of treatment guidelines, randomized trials regarding the use of diagnostic procedures such as coronary angiography are rarely available. This document uses the ACC/AHA classifications of class I, II, and III. These classes summarize the indications for coronary angiography as follows: Class I: Conditions for which there is evidence and/or general agreement that this procedure is useful and effective. Class II: Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness/efficacy of performing the procedure. Class IIa: Weight of evidence/opinion is in favor of usefulness/ efficacy. Class IIb: Usefulness/efficacy is less well established by evidence/opinion. Class III: Conditions for which there …

Disparities Between Aortic and Peripheral Pulse Pressures Induced by Upright Exercise and Vasomotor Changes in Man

Blood pressures were recorded simultaneously from the aortic arch and radial artery using two manometric systems with identical static and dynamic sensitivities. Measurements were made in four normal young men at rest and upright exercise requiring 29, 49, 78, and 100% of maximal oxygen uptake. Average radial arterial pressure rose from 133/66 mm Hg at rest to 236/58 mm Hg at maximal exercise. At the same time, average aortic pressures were 112/68 and 154/70 mm Hg, respectively. From rest to maximal exercise, pulse pressures at central and peripheral sites increased by factors of 1.95 and 2.60, respectively. Inducing reactive hyperemia in the arm abolished peripheral amplification. This amplification also diminished with time during prolonged heavy exercise. Mean pressures were nearly identical at the two sites at any oxygen uptake; mean pressures rose from 87 to 104 mm Hg from mild to maximal exercise. We conclude that estimates of stress on aortic and cerebral vessel walls and central baroreceptors would be grossly overestimated by use of peripheral pulse pressures.

Temporal Trends in Sudden Cardiac Arrest A 25-Year Emergency Medical Services Perspective

Background—Little is known about temporal trends in survival and prognostic characteristics of patients with out-of-hospital cardiac arrest treated by emergency medical services (EMS). We hypothesized that an evolving combination of beneficial and adverse factors may contribute to temporal patterns of survival. Methods and Results—We evaluated a population-based cohort of EMS-treated adult patients with cardiac arrest (n=12 591) from 1977 to 2001 in King County, Washington. Time was grouped into an initial 5-year period and 5 successive 4-year periods. We sought to determine the potential impact of temporal changes in prognostic factors typically beyond EMS control termed “fate” factors (for example, patient age) and factors implemented by EMS termed “program” factors (programs of dispatcher-assisted cardiopulmonary resuscitation and basic life support defibrillation). Several characteristics associated with survival changed over time. Observed survival did not change over time among all patients with cardiac arrest (OR=0.98 [0.95, 1.01], trend for each successive time period) and improved over time among patients with witnessed ventricular fibrillation (OR=1.05 [1.01, 1.09]). In models that included all patients with cardiac arrest and controlled for fate factors, advancing time period was associated with an increase in survival (OR=1.08 [1.05, 1.11]). Conversely, in models that controlled for program factors, advancing time period was associated with a decrease in survival (OR=0.95 [0.93, 0.98]). Results were similar among patients with witnessed ventricular fibrillation. Conclusions—The static temporal pattern of survival from cardiac arrest appeared to result from an evolving balance of prognostic factors. Programs implemented by EMS appeared to counter adverse temporal trends in prognostic factors typically beyond EMS control.

Acute Respiratory Infections in Children

Accurate prevalence and incidence figures do not exist on a global basis yet available data suggest that acute respiratory infections in children represent a problem of enormous magnitude. World Health Organization (WHO) data from 88 countries representing 1/4 of the worlds population indicate that there are over 666000 deaths annual from acute respiratory infections. Assuming that nonreporting countries have similar mortality rates it can be calculated that there are at least 2.2 million deaths from acute respiratory infections throughout the world each year. Despite the enormity of the problem relatively little is known about the factors that contribute to these deaths in children or adults or about the extent to which they are due to unusual severity of the disease lack of access to the health care system and institutional or social factors. The causative agents are unknown. More knowledge is needed to mount an effective program for the prevention and treatment of acute respiratory infections. In Costa Rica mortality from this disease is 12 times higher in malnourished infants than in those of normal weight. Data from Papua New Guinea indicate that Streptococcus pneumoniae and Hemophilus influenzae are common etiologic agents. More data of this kind are needed from different countries. Also needed is information on the availability and use of adequate medical care. People in developed countries run a greater risk of dying from lung cancer and cardiovascular diseases than do people in developing countries but the chances of dying from acute respiratory infections generally exceed those of dying from lung cancer or cardiovascular disease in the developing countries. When evaluating the seriousness of a public health problem it is important to consider the number of years of life that have been lost as well as morbidity and mortality. If there are 2.2 million deaths in the world from acute respiratory infections in children under the age of 1 year then each year there are almost 200 million death years lost because of acute respiratory infections in the world. Thus on a global scale acute respiratory infections represent a public health problem of greater magnitude than either heart disease or cancer. The fact that the annual WHO budget for heart disease is at least 50 times higher than the budget for all forms of respiratory disease represents seriously misplaced priorities. Properly organized research programs into the etiologic agents involved in acute respiratory infection together with data collection on other contributing factors are required so that effective prevention and treatment programs can be initiated.

Human Cardiovascular Adjustments to Rapid Changes in Skin Temperature during Exercise

In 11 normal men, central circulatory responses were measured while skin temperature was changed in a square-wave pattern during uninterrupted exercise (26% to 64% maximal oxygen consumption). Skin temperature was changed at 30-minute intervals, beginning at 32°C. On raising it to 38.2°C at low oxygen consumption (V˙o2), cardiac output increased 2.5 liters/min, and central blood volume, aortic mean pressure, and stroke volume fell (7%, 7%, and 11%, respectively). Right atrial mean pressure fell 2.2 and 2.3 mm Hg during control and heating periods, respectively. All variables returned to control levels when skin temperature was reduced toward 26.9°C. Raising it to 40°C reproduced these changes with a more clear-cut drop in right atrial mean pressure. Results indicated reduced peripheral venous tone and cutaneous pooling of blood during heating and rapid reversal on cooling. On raising skin temperature to 38.7°C at high V˙o2, cardiac output increased 19% (3.1 liters/min), stroke volume decreased 14%, and central blood volume rose slightly. Aortic mean pressure fell during the control period and was maintained or rose during heating periods. On cooling, central blood volume and stroke volume rose, cardiac output remained elevated, and aortic mean pressure fell. Increases in cardiac output during heating were related to skin temperature and not to V˙o2 or body temperature. At high V˙o2, circulatory adjustments favor metabolic rather than thermoregulatory demands.

Public access defibrillation in out-of-hospital cardiac arrest: a community-based study.

Background—The dissemination and use of automated external defibrillators (AEDs) beyond traditional emergency medical services (EMS) into the community has not been fully evaluated. We evaluated the frequency and outcome of non-EMS AED use in a community experience. Methods and Results—The investigation was a cohort study of out-of-hospital cardiac arrest cases due to underlying heart disease treated by public access defibrillation (PAD) between January 1, 1999, and December 31, 2002, in Seattle and surrounding King County, Washington. Public access defibrillation was defined as out-of-hospital cardiac arrest treated with AED application by persons outside traditional emergency medical services. The EMS of Seattle and King County developed a voluntary Community Responder AED Program and registry of PAD AEDs. During the 4 years, 475 AEDs were placed in a variety of settings, and more than 4000 persons were trained in cardiopulmonary resuscitation and AED operation. A total of 50 cases of out-of-hospital cardiac arrest were treated by PAD before EMS arrival, which represented 1.33% (50/3754) of all EMS-treated cardiac arrests. The proportion treated by PAD AED increased each year, from 0.82% in 1999 to 1.12% in 2000, 1.41% in 2001, and 2.05% in 2002 (P = 0.019, test for trend). Half of the 50 persons treated with PAD survived to hospital discharge, with similar survival for nonmedical settings (45% [14/31]) and out-of-hospital medical settings (58% [11/19]). Conclusions—PAD was involved in only a small but increasing proportion of out-of-hospital cardiac arrests.