Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The records of 598 patients undergoing a thoracic surgical procedure for lung cancer from 1975 through 1989 were reviewed for occurrence of cardiac arrhythmias and myocardial ischemic events. Atrial tachycardias occurred in 16% (94/598); atrial fibrillation was preponderant (87%), followed by supraventricular tachycardia and atrial flutter. Patients with recurrent episodes of dysrhythmias had a significantly higher mortality rate than those without episodes or with a single episode only (17% versus 2.4%; p less than 0.01). Transient ischemic electrocardiographic changes were documented in 23 patients (3.8%) and myocardial infarction in 7 (1.2%). An abnormal preoperative exercise test result and intraoperative hypotension were strongly associated with both dysrhythmia and ischemia (p less than 0.01). Pneumonectomy, ischemic changes on the electrocardiogram, and cardiac enlargement were also associated with arrhythmias (p less than 0.01). A weaker association (p less than 0.05) was found between postoperative arrhythmias and old myocardial infarction (greater than 6 months), arterial hypertension, and heart failure. Pulmonary function had no predictive value in this respect. A history of angina or old myocardial infarction was predictive of transient postoperative myocardial ischemia but not myocardial infarction. Despite improved anesthetic and monitoring techniques and more frequent use of the intensive care unit postoperatively in the last decade, the incidence of arrhythmias after thoracotomy has not decreased. More effective prevention is needed, particularly for patients with defined preoperative and perioperative risk factors.
 ...
PMID:Cardiac arrhythmias and myocardial ischemia after thoracotomy for lung cancer. 155 74

We studied atrial arrhythmias during the first 12 h of admission to the hospital in 266 consecutive patients with acute myocardial infarction who subsequently underwent coronary angiography. Ten patients developed atrial fibrillation, one atrial flutter, and one supraventricular tachycardia. Another five developed sinus dysrhythmias. All of the above patients had an acute inferior myocardial infarction, and in 10 of the 12 patients with supraventricular arrhythmias and in four of five with sinus dysrhythmias, the origin of the sinus node artery started just after an occluded right coronary or left circumflex artery or was involved in the occlusion. Thus, ischemia of the sinus node due to coronary occlusion proximal to the origin of the sinus node artery was a likely cause of these arrhythmias.
 ...
PMID:Early atrial arrhythmias in acute myocardial infarction. Role of the sinus node artery. 155 68

After more than two centuries of administration of digitalis glycosides to patients with cardiac disease, empirical observation and tradition remain the basis for much of the clinical application of these drugs. Many questions remain, and the role of digitalis in the management of congestive heart failure and cardiac rhythm disturbances is changing with improvement in our understanding of the pathophysiology of these conditions and the availability of newer effective agents that may have less potential to cause life-threatening toxicity. Nevertheless, digitalis glycoside therapy is a familiar therapeutic intervention for the majority of physicians and remains appropriate in carefully selected patients. The development of digoxin-specific Fab fragments has led to improvement in treatment of advanced and refractory digitalis toxicity and opens up the possibility of improvement in diagnosis of less clinically obvious cases of digitalis intoxication. The role of digitalis glycosides in the management of supraventricular tachyarrhythmias and congestive heart failure in the presence of sinus rhythm should now be revised. In each of these clinical circumstances, alternative drugs or other modes of therapy have been developed that reduce the dependence of clinicians on digitalis as the sole or primary approach to management. In the immediate management of paroxysmal reentrant supraventricular tachyarrhythmias, verapamil has largely replaced digoxin as the drug of choice, although digoxin has an ancillary role, especially in patients with impaired ventricular function. In the management of patients with atrial fibrillation or atrial flutter with a rapid ventricular response, verapamil or diltiazem and beta-adrenergic-blocking drugs will effectively slow the ventricular response, thus reducing the likelihood of approaching the threshold of digitalis toxicity to achieve adequate rate control. In the treatment of patients with congestive heart failure and normal sinus rhythm, one must now recognize a subset of patients with diastolic rather than systolic dysfunction who are best treated by correcting underlying causes of left ventricular hypertrophy or ischemia rather than inotropic support with cardiac glycosides. Symptomatic patients with dilated ventricles and impaired contractile function should undergo correction of abnormalities of preload with vasodilators acting on the venous bed as well as diuretics, and reduction of elevated afterload with vasodilators that reduce arteriolar resistance and thus improve ventricular emptying.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Current concepts in the use of digitalis. 264 67

Atropine, calcium, calcium-channel blockers, beta-adrenergic-receptor blockers, oxygen, morphine, vasodilators, and potent diuretics are frequently used in advanced cardiac life support (ACLS). Since the last AHA conference on ACLS standards, little controversy has arisen regarding the use of oxygen, morphine, vasodilators, or potent diuretics. In 1979, a full vagolytic dose of atropine was recommended for use early in the course of asystolic or bradycardiac arrest. Since then reports suggest that this higher dose of atropine may be of some limited value in treating this highly resistant form of arrest. The routine use of calcium for asystole, bradycardiac arrest, and electromechanical dissociation has come under intense scrutiny. Studies have failed to demonstrate improved survival and have found potentially deleterious levels of serum calcium when calcium was administered according to AHA standards. It is also possible that postanoxic cerebral injury is exacerbated by the use of calcium. No controversy exists, however, concerning the use of calcium for the moribund patient with possible hypocalcemia or with an excess of calcium-channel blockers. The use of calcium-channel blockers has been advocated to prevent or retard the intracellular accumulation of calcium, which may cause irreversible postanoxic tissue damage. Calcium-channel blockers may also be useful in preventing or decreasing cerebral and coronary arteriospasm. These drugs have antianginal properties that may decrease ischemia. The antiarrhythmic effect of verapamil is particularly useful in the treatment of uncomplicated paroxysmal supraventricular tachycardia. Verapamil and diltiazem slow conduction through the atrioventricular node and may be used to slow the ventricular response in atrial fibrillation and flutter.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Cardiovascular pharmacology. III: Atropine, calcium, calcium blockers, and beta-blockers. 287 54

Four cases of sudden cardiac death during ambulatory Holter monitoring are described. All had coronary arterial disease. Two patients were on antiarrhythmic drug therapy and both had a prolonged QTc-interval on their resting electrocardiogram. The predominant rhythm was sinus rhythm in all. In one patient, severe bradycardia terminated in asystole. In the remaining 3 patients, ventricular flutter (which was initiated in 2 instances by a short run of polymorphous ventricular tachycardia) degenerated into ventricular fibrillation. The lethal event was triggered once by an early cycle ventricular premature beat and twice by late cycle ventricular premature beats. There was no specific pattern of warning arrhythmias preceding sudden cardiac death. Signs of ischemia/sympathetic overactivity preceding sudden cardiac death were found in 3 patients. Autopsy studies were performed in 2 patients and revealed acute ischemic myocardial damage.
 ...
PMID:Sudden death during ambulatory Holter monitoring. 362 22

Two young males who had no organic heart disease died unexpectedly during the night. In one patient, the monitor ECG showed a sinoatrial block and the electrophysiologic study revealed a sinoatrial conduction time at the upper limit of normal and a prolonged PA interval. The surface ECG showed left axis deviation. Ventricular ectopic beats were confined to the night when he died from ventricular flutter. The ECG of the other patient was normal except for the change in QRS configuration found when the preceding RR interval was prolonged, suggesting a phase 4 block in intraventricular conduction. He was completely free from arrhythmia except for the ventricular ectopic beats which developed around 9:00 p.m. and the ventricular flutter following an R-on-T type ventricular ectopic beat which resulted in death during the night. The autopsy showed no organic heart disease. ST elevation suggestive of acute ischemia was not found and the QT intervals were normal in both cases. No electrolyte imbalances were found. These 2 cases can be diagnosed as pokkuri disease which is well known in Japan. The victims are exclusively young males who have no apparent diseases to which death can be attributed.
 ...
PMID:Sudden nocturnal death in young males from ventricular flutter. 405 56

A survey was made on a population of 6059 subjects aged more than 60 years with the aim to assess 1. the prevalence of heart arrhythmias and 2. the relationships between arrhythmias and some other ecg alterations. Arrhythmias resulted present in 29.0% of the whole population with a significantly higher prevalence among males (30.7% vs 28.1%, P less than 0.05) and among subjects over 75 years of age (33.2% vs 23.9%, P less than 0.001). Supraventricular extrasystoles (SE, 11.55%), atrial fibrillation (AF, 10.44%) and ventricular extrasystoles (VE, 8.91%) were the most frequent arrhythmias, followed by sinus bradycardia (SB, 2.04%), sinus arrhythmia (SA, 1.35%), atrial flutter (AFL, 1.09%) and junctional rhythms (JR, 0.20%). AF and AFL resulted significantly more frequent among females, whilst SE, VE and SB were more frequent among males. All the above arrhythmias, with the exception of AFL and JR resulted significantly more frequent among subjects over 75. A significantly higher prevalence of ecg signs of left ventricular hypertrophy, ischemia, previous myocardial infarction (MI) and of the so-called "minor" T-wave changes (MTC) was found among the subjects with arrhythmia as compared with those free from rhythm disturbances. Ecg signs of MI and MTC were significantly more frequent among males and MTC were more frequent among females and among subjects over 75. It is concluded that in an old person the presence of an arrhythmia should lead to a careful evaluation of the general and cardiological clinical situation in order to avoid 1. to prescribe an unnecessary and potentially dangerous antiarrhythmic treatment, and 2. to misdiagnose an underlying clinical condition liable to a decisive improvement under adequate treatment.
 ...
PMID:[Arrhythmias in the elderly]. 619 Jan 9

It was the aim of this study to investigate (1) whether preconditioning modifies the fatty acid (FA) composition of myocardial phospholipids (PL), (2) whether a previous modification of membrane PL composition by the administration of coconut oil or fish oil influences the preconditioning, and (3) to compare the protective effects of preconditioning to those of dietary fish oil. To this end, three groups of rats were given during 10 weeks either a standard diet, or a standard diet + 10% coconut oil, or a standard diet + 10% fish oil. The preconditioning was performed in situ in the anesthetized open-chest rats by 2 cycles of 3 min left anterior descending coronary artery occlusion and 10 min reperfusion. It was followed by a 40 min ischemia and a 60 min reperfusion. ECG was recorded and used for the continuous count of the salves of extrasystoles, ventricular flutter and fibrillation. These rhythm disturbances were subsequently added and evaluated as total arrhythmias. The FA of tissue PL were analyzed in a sample of the ischemic zone the size of which was determined by means of malachite green. Coconut oil diet (rich in saturated FA) modified slightly the myocardial PL by increasing oleic acid and decreasing linoleic acid and resulted in the highest incidence of arrhythmias. Fish oil diet had the opposite effect in modifying drastically the PLFA (replacement of the n-6 FA by the n-3 FA) and minimizing significantly the arrhythmias in comparison with the standard diet group.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Myocardial protection by ischemic preconditioning: the influence of the composition of myocardial phospholipids. 765 79

With rapid advances occurring in both basic and clinical electrophysiology, the gap between the two disciplines appears to be widening rather than narrowing. In most instances, we cannot apply the knowledge derived from cellular studies directly to clinical practice. Monophasic action potential (MAP) recording by contact electrode technique allows us to measure basic electrophysiological phenomena in the human heart and thus provides an important bridge between basic and clinical electrophysiology. MAP recordings produce the time course of cellular repolarization during cycle length changes and antiarrhythmic drug administration, lending insights into use dependency and reverse use dependency of antiarrhythmic drug effects in the clinical electrophysiology laboratory. The ability to deliver electrical stimuli at the MAP recording site further allows one to investigate drug-induced postrepolarization refractoriness. MAP recordings provide precise local activation times, important for mapping of abnormal ventricular activation, and detect areas of abnormal repolarization due to ischemia or scarring. MAP recordings are uniquely suited to detect early and delayed afterdepolarizations in the human heart, thereby helping to unravel the arrhythmia mechanisms in the long QT syndrome. By embedding the MAP electrode in a radiofrequency electrode, arrhythmogenic foci may be both detected and ablated. In many instances, MAP recordings are more accurate than ECG tracings in defining and distinguishing ventricular fibrillation and ventricular tachycardia. This can be of clinical importance during testing of the implantable cardioverter/defibrillator. An area of growing interest is stretch-activated arrhythmias. Here, MAP recordings are of particular value because no other method is available to record mechanically induced electrophysiological changes in the vigorously beating heart. It can be expected that MAP recordings will, in the future, provide this important bridge between "cell and bedside" also in atrial tachyarrhythmias, such as in atrial fibrillation and flutter.
 ...
PMID:Bridging the gap between basic and clinical electrophysiology: what can be learned from monophasic action potential recordings? 780 22

Continuous ambulatory ECG (CAECG) monitoring has been advocated as an effective low-cost preoperative method for detecting silent myocardial ischemia in patients undergoing peripheral vascular surgery. In addition, silent ischemic events are associated with an increased incidence of postoperative myocardial infarctions. Ninety-six patients (mean age 73 years) admitted for elective aortic (24) or infrainguinal (72) operations over a 2-year period underwent 24-hour two- or three-lead CAECG monitoring. Results were reviewed by a single cardiologist blinded to the study. The criterion for ischemia was ST segment depressions of 1 mm or greater for 40 seconds or more 60 msec after the J point. Postoperative myocardial infarction was determined by ECG changes and/or elevated serum creatinine phosphokinase with positive MB isoenzymes. Risk factors included hypertension (71%), history of coronary artery disease (66%), smoking (61%), and diabetes mellitus (47%). Nine out of 96 patients (9.4%) had a positive CAECG test for silent myocardial ischemia. Only one patient (11.1%) developed postoperative myocardial infarction and there were no deaths in this group. The incidence of postoperative myocardial infarction in the nonischemic group was 16.1% (14/87). However, the mortality in this group was 6.9% (6/87). New and malignant arrhythmias requiring preoperative medical intervention were observed in seven patients (7.4%): two cases of ventricular tachycardia and five cases of atrial flutter/fibrillation. Contrary to previous reports, CAECG monitoring for silent ischemia was not a significant predictor of postoperative myocardial infarction or mortality in our patient population. However, we continue to recommend the preoperative use of CAECG monitoring as a diagnostic tool for unsuspected malignant arrhythmias.
 ...
PMID:Silent myocardial ischemia is not predictive of myocardial infarction in peripheral vascular surgery patients. 851 16


1 2 3 Next >>