Showing papers by "Elliott M. Antman published in 1986"

Transtelephonic electrocardiographic transmission for management of cardiac arrhythmias.

Abstract: Brief periods of transtelephonic electrocardiographic transmission conducted at periodic intervals or during sporadic symptoms may provide an inexpensive and reliable alternative to extended ambulatory electrocardiographic tape recordings. Sixty-one patients were enrolled in a transtelephonic electrocardiographic transmission program. In 51 patients with documented arrhythmias (group I), telephone electrocardiographic transmissions were used to monitor antiarrhythmic drug therapy. In 10 patients, telephone electrocardiographic transmission was used in an attempt to diagnose infrequent symptoms suggestive of arrhythmia (group II). Of the 650 telephone electrocardiographic transmissions received, 73 (11%) revealed a clinically significant event, whereas 577 (89%) did not show any significant disturbances of cardiac rhythm. Of the 61 patients entered into the program, 29 (48%) had a clinically significant event identified during 1 or more transmissions. In group I, transtelephonic electrocardiographic transmission prompted a change in therapy in 37% of the patients. Of the 10 patients in group II, clinically significant events were noted during telephone electrocardiographic transmissions in each patient. Assuming a yield of 1 clinically significant event detected per 10 telephone electrocardiographic transmissions and a similar yield on long-term ambulatory electrocardiographic recordings, use of telephone electrocardiographic transmissions offers a cost-effective means of following patients with significant cardiac arrhythmias who are receiving potent antiarrhythmic drugs. In addition, telephone electrocardiographic transmission is a suitable diagnostic technique for patients with infrequent symptoms suggestive of cardiac arrhythmias.

The scintigraphic evaluation of myocardial infarction and regional ventricular performance using technetium-99m hexakis (t-butylisonitrile) technetium (I) (TBI): A new myocardial imaging agent

Abstract: Technetium-99m hexakis (t-butylisonitrile) technetium (I) (99mTc-TBI) is a new myocardial perfusion imaging agent. To determine its potential in the evaluation of myocardial infarction, 15 patients with suspected or confirmed acute infarction were studied by bedside imaging in the coronary care unit. Good-quality planar scintigrams in multiple projections were obtained in 13 patients. Gated perfusion studies were performed in 14 patients, and for comparison 13 of these were restudied 24–72 h later by standard gated equilibrium blood pool radionuclide ventriculography. Conventional and planar scintigraphic criteria for myocardial infarction (acute or old) agreed in 12 (92%) patients (k=0.81, p<0.05). All the infarctions detected by scintigraphy were associated with electrocardiographic Q-waves. Localization of infarction by the electrocardiogram and scintigraphy exhibited moderate agreement (k=0.49, p<0.1). Regional wall motion analysis by standard radionuclide ventriculography and gated 99mTc-TBI scintigraphy were in complete agreement for 25 (64%) of 39 left ventricular segments (k=0.35, p<0.05). However, in 7 other segments, associated with areas of infarction, regional wall motion abnormalities were noted only on gated 99mTc-TBI scintigraphy. Therefore, 99mTc-TBI scintigraphy can readily provide data on regional myocardial perfusion and wall motion, permitting detection and localization of areas of myocardial infarction. The superior imaging properties, ready availability and low cost of 99mTc point to the considerable potential value of 99mTc-TBI in assessing patients with suspected or confirmed myocardial infarction.

Coronary Care Medicine: A Practical Approach

Abstract: 1. Pathogenesis and Pathology of Ischemic Heart Disease Syndromes.- 2. Clinical Presentation of Ischemic Heart Disease.- 3. Routine Management of Myocardial Infarction.- 4. Cardiac Arrhythmias During Acute Myocardial Infarction.- 5. Management of Cardiac Arrhythmias not Associated with Acute Myocardial Infarction.- 6. Pharmacological Therapy of Cardiac Arrhythmias.- 7. Cardioversion and Defibrillation.- 8. Atrioventricular and Intraventricular Conduction Defects.- 9. Temporary and Permanent Pacemaker Therapy.- 10. Cardiac Arrest and Resuscitation.- 11. Hemodynamic Monitoring.- 12. Complications of Acute Myocardial Infarction.- 13. Myocardial Infarct Size Reduction.- 14. Coronary Artery Spasm.- 15. Post-Hospital Management of Myocardial Infarction.- 16. Prognosis After Hospitalization with Chest Pain or Myocardial Infarction.

Pharmacological Therapy of Cardiac Arrhythmias: Antiarrhythmic Agents, Beta Adrenoceptor Blocking Agents, and Digitalis Glycosides

Abstract: The ideal approach to the management of cardiac rhythm disorders depends on the following: 1. Proper identification of the arrhythmia. 2. An understanding of the natural history of the arrhythmia in a particular patient. 3. An understanding of the multiple factors that may precipitate and maintain a cardiac rhythm disturbance in a particular patient. 4. An understanding of the pharmacology of the numerous antiarrhythmic drugs available. 5 An appropriate clinical assessment of the risk to the patient due to the cardiac arrhythmia versus the side effects that might ensue upon initiation of treatment with an antiarrhythmic drug.

Complications of Acute Myocardial Infarction

Abstract: Acute myocardial infarction is often accompanied by some degree of heart failure. In general, anterior infarction is associated with more severe pulmonary congestion than is inferior infarction. Inferoposterior infarction is occasionally associated with the syndrome of right ventricular infarction, i.e., hypotension with or without bradycardia, clear lung fields, and elevated right heart filling pressures. It is common for patients to have no symptoms of heart failure when an S4 gallop rhythm is present (usually reflecting elevated left ventricular end-diastolic pressure) , and about half the patients with significant pulmonary congestion evident on chest x-ray have no abnormal physical findings.

Myocardial Infarct Size Reduction

Abstract: In 1912, Herrick concluded his classic article by presenting a logical approach to the treatment of myocardial infarction: “the hope for the damaged myocardium lies in the direction of securing a supply of blood through friendly neighbouring vessels so as to restore as far as possible its functional integrity” [1]. Thus, this distinguished physician anticipated by more than half a century the concept of limiting infarct size.

Cardioversion and Defibrillation

Abstract: Although the application of electrical energy to the heart had been investigated in the 18th century, it was not until the first half of the 20th century that reference was made to the clinical use of electrical shocks to revert abnormal cardiac rhythms Several recent reviews have summarized historical milestones in the development of devices capable of delivering specified electrical charges to the heart [1–4] Early studies utilized alternating current (AC), employing 60-cycle AC of 15 to 20 amperes and 120 to 130 volts Although AC discharges are capable of transthoracic defibrillation of the human heart, they are not suitable for correcting arrhythmias in man because they may lead to substantial deterioration in ventricular function and expose the patient to the risk of ventricular fibrillation [5] The development of capacitors capable of delivering single-pulse discharges set the stage for the production of the cardioversion/defibrillation apparatus in use today (figure 7–1)

Temporary and Permanent Pacemaker Therapy

Abstract: Temporary cardiac pacing can be achieved by four basic techniques: thump pacing, external transthoracic electrical pacing, percutaneous transthoracic pacing, and transvenous endocar-dial pacing.

Routine Management of Myocardial Infarction

Abstract: Recent changes in the routine management of patients with uncomplicated myocardial infarction (MI) over a 10-year period have been highlighted in a publication that surveyed general and family practitioners, internists, and cardiologists in the United States [1]. This survey revealed that half the myocardial infarcts were regarded as uncomplicated. Because intensive or coronary care facilities were widely available in both metropolitan and rural areas, more than 90 per cent of physicians routinely hospitalized their patients. Between 1970 and 1979, the use of intensive care and coronary care facilities increased and the availability of progressive care facilities rose from 33 to 75 per cent.

Atrioventricular and Intraventricular Conduction Defects

Abstract: For proper diagnosis and management of conduction defects it is important to understand the anatomy and vascular supply of the specialized conduction system of the heart (figure 8–1).

Cardiac Arrest and Resuscitation

Abstract: In the cardiac intensive care unit (ICU) staff should be mentally and physically equipped to deal with sudden cardiac arrest and initiate prompt resuscitative efforts. Such efforts fundamentally involve a coordinated system to provide artificial ventilation and artificial circulation (i.e., basic cardiopulmonary resuscitation [CPR]) that may be supplemented by advanced cardiac life support systems (e.g., oxygen, defibrillation, specialized medications). Many of the elements of advanced cardiac life support are reviewed in detail in other chapters of this book, as follows : 1 Recognition and treatment of arrhythmias (chapters 4, 5, and 6). 2 Cardioversion and defibrillation (chapter 7). 3 Recognition and treatment of conduction disorders (chapters 8 and 9). 4 Recognition and treatment of hemodyna-mic disorders, including heart failure and car-diogenic shock (chapters 11 and 12).

Prognosis After Hospitalization with Chest Pain or Myocardial Infarction

Abstract: In the late 1960s and early 1970s, a decline in coronary heart disease mortality was noted in different parts of the world. This downward trend has since continued in North America, Belgium, Finland, Israel, Japan, Australia, and New Zealand [1–3], and data from Australia suggest that it is evident in all age groups [4]. In contrast, in most eastern European countries, Russia, and Sweden, death rates from coronary heart disease are increasing.

Clinical Presentation of Ischemic Heart Disease

Abstract: American physicians refer to James B. Herrick as the first to describe the clinical presentation of a nonfatal myocardial infarction in 1912. In his description Herrick indicated his familiarity with an earlier report by Obraztsov and Strazhesko in a German translation in which they discussed five cases of myocardial infarction, three of which were confirmed by autopsy A 49-year-old artillery man was admitted to the medical division of the Aleksandrovsky Hospital on December 5, 1899. For 12 days prior to admission, he had experienced substernal pain radiating to the throat, head and left arm. The attacks lasted 2 to 4 hours and after a brief pause would begin again. During the attacks he experienced shortness of breath and the inability to breathe deeply. The chest pain was so severe that the intern on my service, who was young and inexperienced, in response to my question as to the patient’s admitting diagnosis responded “rheumatism of the chest.” Objective Findings: He was well nourished and well developed. There was moderate cyanosis of the mucous membranes. His facial expression revealed distress from the substernal pain which radiated to the neck and head. No vessel motion was visible in the neck. The respiratory and abdominal organs were without abnormalities. The cardiac impulse was not visible, but was weakly palpable in the 5th intercostal space in the left mammary line. The heart sounds were distant and there were no murmurs. Direct auscultation revealed presystolic splitting of the first sound. Pulse 90 and barely palpable. Rhythm regular. After the initial examination the diagnosis of coro- nary thrombosis was made. The patient died 4 days later on December 9, 1899. Autopsy Findings: On cross section of the left ventricle its entire thickness was of a muddy-gray yellowish color, as seen with necrosis. These changes occurred in almost the entire wall of the left ventricle and septum. Near the origin of the right coronary artery there was 1 cm long yellowish projection from the wall of the vessel producing some luminal narrowing. The changes in the left coronary were more severe. The left anterior descending coronary artery was occluded by grayish-red thrombus 1 cm long and 1 mm in diameter. The left circumflex was occluded by a 3 cm long soft yellow thrombus.

Pathogenesis and Pathology of Ischemic Heart Disease Syndromes

Abstract: The terms “arteriosclerosis” and “athero sclerosis”are often confused in descriptions of experimental and clinical arterial lesions. Arteriosclerosis is a general term implying arterial hardening without respect to a specific etiology, examples being atherosclerosis, Monckeberg’s medial calcification, and arteriolosclerosis (small vessel disease) [1]. Atherosclerosis refers to a specific disease process characterized by the development of yellow, lipid-laden plaques. There are three pathological stages in such plaque development: 1. The fatty streak, which is a yellow, generally flat patch on the intima made up of accumulated lipid-containing smooth muscle cells. Commonly found in young individuals fatty streaks probably have no pathological significance in many cases. 2. The fibrous plaque, which is an intimai deposit of lipid-laden smooth muscle cells surrounded by collagen, elastic fibers, and extracellular lipid. Fibrous plaques may or may not arise from fatty streaks and can exist without causing significant obstruction of the vascular lumen. 3. The complex plaque, which is a fibrous plaque that has progressed to include calcification, hemorrhage, cell necrosis, an inflammatory reaction, and extension to the arterial media. Adventitial fibrosis and inflammation may be present.

Post-Hospital Management of Myocardial Infarction

Abstract: Over the last decade there has been considerable interest in analyzing differences in outcome among patients with “nontransmural” versus “transmural” infarction [1–10]. Although these terms have been used for many years to classify patients after serial electrocardiographic evaluation, the correlation between “transmural” and Q-wave infarction or between “nontransmural” and non-Q-wave infarction with regard to pathological findings is imperfect [11]. Infarctions found to be transmural on pathological examination can occur in the absence of Q waves on the ECG, while those found to be nontransmural may be associated with the appearance of new Q waves [12]. We prefer to describe infarcts as being either Q-wave or non-Q-wave on the basis of serial ECG evaluation. In most instances of Q-wave infarction, the infarct will most likely, but not necessarily, be transmural.

Management of Cardiac Arrhythmias not Associated with Acute Myocardial Infarction

Abstract: Modern coronary care units, particularly those in large university medical centers, usually serve as cardiac intensive care units. Of course, patients with acute myocardial infarction (MI) are admitted to such units, but so are patients with a variety of cardiac arrhythmias that are not the result of acute MI. Clinicians caring for patients in cardiac intensive care units must be prepared to deal with disorders of sinus node function, supraventricular arrhythmias (including those associated with preexcitation syndromes), and recurrent ventricular arrhythmias. Often the patient has been resuscitated from one or more bouts of sudden cardiac death; to prevent recurrences, a therapeutic program of anti-arrhythmic drugs at times combined with sophisticated pacemaker and cardiac surgical techniques may be needed.