Machines in Our Hearts

Contents

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pp. vii-viii

List of Illustrations and Tables

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pp. ix-x

Acknowledgments

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pp. xi-xiii

Introduction

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pp. 1-13

In the spring of 1976, Elmer A. Braun, of Charleston, West Virginia, underwent a physical examination when his former employer changed insurance carriers for its retired workers. An electrocardiogram (ECG) revealed that something wasn’t right with Braun’s heart-beat. ...

CHAPTER 1: Heart Block and the Heart Tickler

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pp. 14-35

Modern cardiac pacemakers and other implantable devices that manage disorders of heart rhythm are a result of decades of scientific research about the workings of the normal heartbeat. But there was never a simple and certain route ‘‘from bench to bedside.’’ ...

CHAPTER 2: The War on Heart Disease and the Invention of Cardiac Pacing

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pp. 36-57

As a doctor, Paul M. Zoll had a two-track career: he did laboratory research at the Beth Israel Hospital in Boston and he also maintained a large general practice, even making house calls. The medical world took notice when Zoll announced in 1952 that he had successfully kept a patient alive through numerous episodes of ventricular standstill using a bedside device that delivered electrical pulses to the heart.¹ ...

CHAPTER 3: Heart Surgeons Redefine Cardiac Pacing

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pp. 58-82

Reports of Paul Zoll’s success at resuscitating patients from standstill of the heart both encouraged others to experiment with cardiac pacing and freed them to do so. Within a few years, many physicians reported in print on their own experience either with the Electrodyne pacemaker or similar devices built for them. ...

CHAPTER 4: The Multiple Invention of Implantable Pacemakers

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pp. 83-106

Despite the confused discussion at the Rockefeller Conference in October 1958, pacing the heart for weeks or months at a time loomed as a desirable next step in part because heart specialists had begun to realize that quite a few adults developed heart block or chronically slow heartbeats in late middle age. ...

CHAPTER 5: Making the Pacemaker Safe and Reliable

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pp. 107-135

The earliest pacemaker implanters were often stunned at their patients’ sudden and dramatic improvement. At a medical meeting around 1963, a well-known cardiologist told surgeon Victor Parsonnet that he doubted whether pacing was an effective treatment. ...

CHAPTER 6: The Industrialization of the Pacemaker

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pp. 136-160

A handful of physicians contributed important innovations during the 1960s, but business firms were increasingly shaping the cardiac pacemaker and the field of pacing. The decade witnessed the rise of a pacemaker manufacturing industry in the United States and western Europe that consisted of seven or eight principal companies. ...

CHAPTER 7: The Pacemaker Becomes a Flexible Machine

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pp. 161-185

A succession of radical innovations in cardiac pacing broke up the brief era of stability that had begun in the late 1960s. New themes emerged: doctors’ uneasiness about the growing complexity of cardiac pacing, the public’s anxieties about the possible dangers of a life- sustaining technology, and broadly shared concerns about the growth dynamic of the field of pacing. ...

CHAPTER 8: Slowing the Pace: The Industry’s Time of Troubles

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pp. 186-208

Ever since the early 1970s, physicians and manufacturers in the field of heart-rhythm management have had to operate in a highly unsettled political environment in the United States. The second decade of implanted cardiac pacemakers proved a watershed because the federal government shifted course to try to ensure the safety and effectiveness of medical devices that would be implanted within the body. ...

CHAPTER 9: Competition through Innovation: Accelerating the Pace of Change

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pp. 209-234

By 1980, virtually all pacemakers depended on hybrid integrated circuitry and lithium batteries that would reliably manage the heartbeat for eight years or more. Using an external programmer, the physician could alter the pacer’s behavior in various ways and, in a few models, also interrogate the implanted device through coded magnetic signals and download information about its performance, the condition of the battery, and the behavior of the patient’s heart. ...

CHAPTER 10: Preventing Sudden Cardiac Death: The Implantable Defibrillator

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pp. 235-262

In the 1980s, the pacemaker industry transformed itself into the ‘‘cardiac rhythm management industry’’ by introducing an entirely new kind of implantable machine that halted ventricular tachycardia (VT—a ventricular rate of more than 100 beats per minute) and that most sinister of rhythm disturbances, ventricular fibrillation (VF—random electrical activity in the ventricles with no organized ventricular beat). ...

CHAPTER 11: The 1990s and Beyond: ‘‘When Life Depends on Medical Technology’’

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pp. 263-289

The use of pacemakers and ICDs has continued to grow during the 1990s (see appendix B); unfortunately, estimates of the number of implantations vary greatly, ranging from 192,000 to 317,000 for 1997. Industry analysts believed that cardiac pacing was growing at about 6 percent a year in units sold, about 8 to 10 percent in revenues as purchasers moved from one product generation to the next. ...

APPENDIX A: Device Reliability, Qualification Tests, and Improvements

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pp. 291-293

APPENDIX B: Number of Implantations

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pp. 294-295

APPENDIX C: ICHD Pacemaker Identification Code

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pp. 296-

Abbreviations

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pp. 297-

Notes

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pp. 299-352

Bibliographical Note

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pp. 353-359

My study traces the careers of a pair of artifacts, the pacemaker and the implantable defibrillator, and the ideas and aspirations of the social groups that have created and managed them. Historians of medicine and technology told us relatively little about the invention and social shaping of medical devices such as these until interest in the subject began to burgeon in the last twenty years as an aspect of the broader societal debate over...

Index

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pp. 361-370