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Progress notes in cardiology
Progress Notes in Cardiology Edited by EMANUEL GOLDBERGER, M.D., F.A.C.C. New York, New York
Electrocardiographic
Analysis by a Computer
T
is put in operation. This allows an electrocardiographic technician to utilize the system without any further training. The field recording sy-stem records a patient code, or hospital number, on both the magnetic tape and paper record. Each time the lead selector is turned, the system also records a lead code. This saves time for the technician and preserves identity of the leads. The central unit, on receipt of a magnetic tape, can identify and read, without stopping, as many electrocardiograms as are on a tape. The unit consists of a control console, a digital computer and an automatic typewriter for the printout. The control console houses tape playback units, a system to identify the patient and lead codes, an analog-to-digital converter, and ancillary- control and checking devices. With automation, a large number of electrocardiograms can be surveyed rapidly. This can diminish and improve the work load of the epidemiologist and personnel of the heart station and may eventually aid the practitioner when the services of an electrocardiographer are not available to him. With an accessible electronic-computer system, the services of a cardiologist can be better utilized to study only those tracings that are outside normal limits. More important, such a system can providewhat phy-sicians since, and before, Hippocrates have searched for-means to improve basic data in order to improve diagnostic acumen.
ODAY IN medicine, as in most other fields of endeavor, rapid and tireless electronic systems can be envisioned as an integral part of the future to effect economy of human time. In a recent paper, Dr. Cesar A. Caceres (AK/L Int. Med., 111: 114, 1963) describes a model system that demonstrates that phpsicians can utilize electronic instruments to relieve them of routine work. The implication is that utilization of these methods can allow the physician to use his time and efforts to better advantage in diagnosis and care of patients. Electrocardiographic analysis by means of a computer system was attempted as a pilot study because there are several challenging limitations to the extensive use of electrocardiography in screening or epidemiologic studies of large numbers of subjects, in addition to the problems encountered by the practicing physician concerned with the single patient’s electrocardiogram. At present, the computer-electronic system consists of peripheral and central equipment. The peripheral equipment’s function is to record the data. It can be utilized anywhere. With this equipment the electrocardiogram is made available in routine form on paper for conventional analysis and is also simultaneously available by FM modulation on magnetic tape. The equipment consists of a conventional electrocardiograph combined with a tape recorder that has been stripped of its controls so that it records only when the electrocardiograph
Anticoagulant
System
Therapy
W
in Norway
which can be hoped for under such circumstances is to prevent additional, secondary thrombi locally, or at other sites. 2. The antithrombotic efficacy depends on (a) the level of hypocoagulability actually obtained and (b) the stability of this level. These are critical points too often neglected when therapeutic results are discussed. Results of
HEN ONE is faced with the problem of selecting patients for anticoagulant therapy or for evaluating results of such therapy, there are three main points which must be considered. 1. One is concerned with a prophylactic and not a curative therapy; therefore, it is in fact too late to start prophylaxis when thrombosis has already occurred. The only effect 270
THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Progress
Notes
anticoagulant proph) laxis have often been poor or rqativc, because these points ha\-e been clisregarded. ant! use of anticoagulants as a therapeutic me:ssure has been sometimes unnecessarily criticized. 3. Which patients should be selected for antithrombotic prophylaxis:’ The main criterion for selection must obviousI>- be the patient’s risk of thrombosis in the near or more distant future. If the incidence of thromboembolic complications is ver)- low, even without anticoagulant prophylaxis, there is, of course, little or no indication for preventive measures. Dr. P. A. Owren of Norway has analyzed this problem in a recent paper (,~w/I. Znt. LMed., 111: 158, 1363). He concluded: All patients with mitral \.alvular disease who have experienced embolism should be placed on lifelong anticoagulant prophylaxis. This raises the question of prophylaxis before the first embolic episode, be which may- sometimes catastrophic to the patient. He has for some )‘ears also selected such patients for prophylaxis, based on a calculated high risk of embolism, as evaluated from the clinical condition, the stage of the disea,;e, age of the patient, the presence of atria1 fibrillation, or a large left atrium. Patients with angina pectoris for less than two or three years ,greatly benefit from lon,q term anticoagulant therapy. There is evidence for
AUGUST
1963
in CL+rclioloq
771
assumiqg that early therapy interferes \\-itll t11c natural course of the disease and favors latc Consequently, prophvlasis should prognosis. +he cffvct in be continurd for several years. patients with a history of angina pectoris of more than about three \.ears is not convincing. He did not discuss the prevention of recurrent infarction in survivors of acute myocardial infarction and the place of anticoagulants in peripheral obliterative atherosclerotic disease and in cerebral atherosclerosis, but the basic principles are the same. He believes that the a,qe of the disease is more important than the age of the patient. Following is a list of high priorit)- conditions for long term therap!- based on currently a\Glable evidence: 1. 2. 3. 4.
5.
Rheumatic heart disease with embolism. Angina pectoris of less than two years’ duration. Myocardial inrarction (after the first attack). Thrombosing atherosclerosis in the louver limbs (for protecting against coronarv death). Intermittent cerebral ischemia caused by thrombosis of supplying arteries.
‘This list may well have to be changed when the role of this treatment becomes more clearly defmcd in these and in other conditions.
Electrocardiographic
Analysis by a Computer
T
is put in operation. This allows an electrocardiographic technician to utilize the system without any further training. The field recording sy-stem records a patient code, or hospital number, on both the magnetic tape and paper record. Each time the lead selector is turned, the system also records a lead code. This saves time for the technician and preserves identity of the leads. The central unit, on receipt of a magnetic tape, can identify and read, without stopping, as many electrocardiograms as are on a tape. The unit consists of a control console, a digital computer and an automatic typewriter for the printout. The control console houses tape playback units, a system to identify the patient and lead codes, an analog-to-digital converter, and ancillary- control and checking devices. With automation, a large number of electrocardiograms can be surveyed rapidly. This can diminish and improve the work load of the epidemiologist and personnel of the heart station and may eventually aid the practitioner when the services of an electrocardiographer are not available to him. With an accessible electronic-computer system, the services of a cardiologist can be better utilized to study only those tracings that are outside normal limits. More important, such a system can providewhat phy-sicians since, and before, Hippocrates have searched for-means to improve basic data in order to improve diagnostic acumen.
ODAY IN medicine, as in most other fields of endeavor, rapid and tireless electronic systems can be envisioned as an integral part of the future to effect economy of human time. In a recent paper, Dr. Cesar A. Caceres (AK/L Int. Med., 111: 114, 1963) describes a model system that demonstrates that phpsicians can utilize electronic instruments to relieve them of routine work. The implication is that utilization of these methods can allow the physician to use his time and efforts to better advantage in diagnosis and care of patients. Electrocardiographic analysis by means of a computer system was attempted as a pilot study because there are several challenging limitations to the extensive use of electrocardiography in screening or epidemiologic studies of large numbers of subjects, in addition to the problems encountered by the practicing physician concerned with the single patient’s electrocardiogram. At present, the computer-electronic system consists of peripheral and central equipment. The peripheral equipment’s function is to record the data. It can be utilized anywhere. With this equipment the electrocardiogram is made available in routine form on paper for conventional analysis and is also simultaneously available by FM modulation on magnetic tape. The equipment consists of a conventional electrocardiograph combined with a tape recorder that has been stripped of its controls so that it records only when the electrocardiograph
Anticoagulant
System
Therapy
W
in Norway
which can be hoped for under such circumstances is to prevent additional, secondary thrombi locally, or at other sites. 2. The antithrombotic efficacy depends on (a) the level of hypocoagulability actually obtained and (b) the stability of this level. These are critical points too often neglected when therapeutic results are discussed. Results of
HEN ONE is faced with the problem of selecting patients for anticoagulant therapy or for evaluating results of such therapy, there are three main points which must be considered. 1. One is concerned with a prophylactic and not a curative therapy; therefore, it is in fact too late to start prophylaxis when thrombosis has already occurred. The only effect 270
THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Progress
Notes
anticoagulant proph) laxis have often been poor or rqativc, because these points ha\-e been clisregarded. ant! use of anticoagulants as a therapeutic me:ssure has been sometimes unnecessarily criticized. 3. Which patients should be selected for antithrombotic prophylaxis:’ The main criterion for selection must obviousI>- be the patient’s risk of thrombosis in the near or more distant future. If the incidence of thromboembolic complications is ver)- low, even without anticoagulant prophylaxis, there is, of course, little or no indication for preventive measures. Dr. P. A. Owren of Norway has analyzed this problem in a recent paper (,~w/I. Znt. LMed., 111: 158, 1363). He concluded: All patients with mitral \.alvular disease who have experienced embolism should be placed on lifelong anticoagulant prophylaxis. This raises the question of prophylaxis before the first embolic episode, be which may- sometimes catastrophic to the patient. He has for some )‘ears also selected such patients for prophylaxis, based on a calculated high risk of embolism, as evaluated from the clinical condition, the stage of the disea,;e, age of the patient, the presence of atria1 fibrillation, or a large left atrium. Patients with angina pectoris for less than two or three years ,greatly benefit from lon,q term anticoagulant therapy. There is evidence for
AUGUST
1963
in CL+rclioloq
771
assumiqg that early therapy interferes \\-itll t11c natural course of the disease and favors latc Consequently, prophvlasis should prognosis. +he cffvct in be continurd for several years. patients with a history of angina pectoris of more than about three \.ears is not convincing. He did not discuss the prevention of recurrent infarction in survivors of acute myocardial infarction and the place of anticoagulants in peripheral obliterative atherosclerotic disease and in cerebral atherosclerosis, but the basic principles are the same. He believes that the a,qe of the disease is more important than the age of the patient. Following is a list of high priorit)- conditions for long term therap!- based on currently a\Glable evidence: 1. 2. 3. 4.
5.
Rheumatic heart disease with embolism. Angina pectoris of less than two years’ duration. Myocardial inrarction (after the first attack). Thrombosing atherosclerosis in the louver limbs (for protecting against coronarv death). Intermittent cerebral ischemia caused by thrombosis of supplying arteries.
‘This list may well have to be changed when the role of this treatment becomes more clearly defmcd in these and in other conditions.