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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Maximum exercise testing using treadmill walking and cycle ergometry was compared in 40 male patients who had suffered a myocardial infarction in the preceeding twelve months. Maximum oxygen uptake was on average 17% greater in the treadmill than the cycle test and maximum heart rate was also higher, but the rate pressure product (RPP) was a similar due to a higher blood pressure in the cycle ergometer test. Eleven subjects showe ST-segment depression greater than 1 min and eight subjects showed ST-segment elevation greater than 1 mm. There was a close relationship (r2 = 0.96) between the magnitude of ST-segment changes in the two tests. Four subjects showing ST depression of 1 mm in the treadmill test showed depression during the cycle ergometer test which was less than this conventionally "positive" value. In these subjects RPP was lower during cycling than in treadmill walking. With both tests maximum ST-segment changes were measured immediately on stopping exercise: resolution of ST depression was more rapid than ST elevation. The two exercise testing modes are closely comparable in their ability to reveal changes of myocardial ischemia.
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PMID:Comparison of the electrocardiographic changes induced by maximam exercise testing with treadmill and cycle ergometer. 63 26

The changes in left ventricular (LV) dynamics induced by brief periods of ischemia (100 seconds) and subsequent reperfusion were analyzed in conscious dogs. Global LV ischemia, induced by partially occluding the left main coronary artery, reduced LV flow homogeneously and impaired LV function as reflected by decreases in LV stroke "work" (89 +/- 4% M +/- SE), systolic shortening (72 +/- 4%), velocity of shortening (56 +/- 6%), LV systolic pressure (34 +/- 5%), and dP/dt (59 +/- 6%). Regional LV ischemia, induced by occluding either the left circumflex or anterior descending coronary artery completely, reduced flow to the ischemic segment (82 +/- 3%) while decreasing segment work (96 +/- 5%), shortening (82 +/- 3%), and velocity of shortening (70 +/- 5%), with minimal depression of overall LV function. In both groups the extent of shortening was reduced more rapidly and greater (P less than 0.01) than shortening velocity. Moreover, with localized ischemia, segment work was reduced more (P less than 0.01) than shortening. With reperfusion, a transient overshoot in function above preischemic control levels was observed in both groups (global work increased by 60 +/- 12% and regional work by 28 +/- 4% above control). This overshoot was not dependent on adrenergic mechanisms, but was prevented by inhibiting reactive hyperemia. Thus myocardial ischemia induces a dissociation between extent and rate of myocardial shortening. A further dissociation between shortening and work is apparent with regional ischemia. After reperfusion there is a transient overshoot in function which appears to be dependent upon the associated reactive hyperemia.
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PMID:Initial myocardial adjustments to brief periods of ischemia and reperfusion in the conscious dog. 65 61

A multicenter study of rest and exercise thallium-201 myocardial imaging in 190 patients from five centers was performed. Exercise images were obtained after graded treadmill or bicycle stress with use of five different gamma camera models and were interpreted by the originating investigator without knowledge of other clinical data. Of 42 patients with less than 50 percent coronary stenosis, 4 (10 percent) had a resting image defect, 1 (2 percent) a new exercise defect and 5 (12 percent) either a resting or an exercise image defect, or both. Of 148 patients with coronary stenosis of 50 percent or greater, 64, (45 percent) had an image defect in the study at rest, 90 (61 percent) had new or increased defects after exercise, and 115 (78 percent) had resting or exercise defects, or both. New exercise image defects were more common than exercise S-T depression (90 of 148 [61 percent] versus 62 of 148[42 percent]; P less than 0.01). In a second group of 111 patients with acute myocardial infarction studied at three centers, 90 patients (81 percent) had image defects compared with 71 (64 percent) two had new electrocardiographic Q waves (P less than 0.01). Smaller infractions, as assessed with serum enzyme values, and diaphragmatic infarctions were less commonly detected than larger or anterior infarctions. These findings suggest that myocardial imaging complements the electrocardiographic identification of acute myocardial infarction of exericse-induced myocardial ischemia.
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PMID:Myocardial imaging with thallium-201: a multicenter study in patients with angina pectoris or acute myocardial infarction. 68 46

3 patients with different clinical and electrocardiographic manifestations of coronary artery spasm are discussed. All 3 patients had anginal attacks at rest. In addition, 2 of these patients, who did not have significant preexisting narrowing of their coronary arteries, also had anginal pain related to exercise. During pain, 1 patient showed ST-segment elevation, the other ST-segment depression, while the third showed ST-segment depression shortly followed by ST-elevation on the electrocardiogram. At coronary angiography, spontaneous or induced spasm of one of the major coronary arteries could be demonstrated in all 3 patients. In 2 cases, sublingual nitroglycerin failed to completely relieve the spasm. This raises the question whether a residual stenosis after NTG conclusively proves a fixed organic narrowing. It is concluded that the clinical spectrum of spasm of the coronary arteries is wider than was originally reported by Prinzmetal and coworkers. Clinical and electrocardiographic manifestations are probably dependent on the site and severity of the spasm, which may cause different degrees of myocardial ischemia.
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PMID:Variant forms of angina pectoris. 71 Apr 90

One hundred patients with angina pectoris underwent 16-point electrocardiographic (ECG) mapping of the left hemithorax during a standardised exercise test. Forty-five patients had maximum ST-segment depression at position V5, while 35 had no ECG signs of ischaemia at this position. In 20 V5 was on the edge of the precordial area, which showed less severe ST-depression than the central positions. An Oxford ECG recorder and highspeed analyser were modified and used in 50 of the patients with daily angina for recording ST-segment changes over 24 hours. Serial 24-hour ambulatory recordings from the edge of the precordial area of ischaemia identified during exercise detected a mean of only 14 +/- SD 3% of the episodes of ST-segment changes recorded from the centre of the same area. Only 16 +/- 2% of the episodes detected by ECG were accompanied by chest pain. More episodes occurred between 4 am and 6 am than at any other time during the night. This study shows the importance of recording ECG evidence of ischaemia from the precordial position showing maximum changes during exercise. ECG evidence of ischaemia occurs more frequently than anginal pain. These objective measurements add important information to the frequency of chest pain reported by patients with ischaemic heart disease.
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PMID:Myocardial ischaemia in patients with frequent angina pectoris. 72 37

A technique for praecordial surface mapping of the exercise electrocardiogram is described. This showed the area, time course, and severity of ST segment depression as projected onto the front of the chest after exercise. Twenty normal volunteers and 20 patients with coronary artery disease have been studied. No changes were seen after exercise in the normal subjects but areas of ST segment depression appeared in all 20 patients with angina pectoris. In 5 of the 20 patients with coronary artery disease, the exercise test was repeated on a later date. There were no significant differences in the area of severity of electrocardiographic abnormalities recorded during the two tests. This technique may prove to be useful for diagnosis and assessing medical and surgical treatments in patients with ischaemic heart disease.
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PMID:A method for praecordial surface mapping of the exercise electrocardiogram. 73 91

The reproducibility of serial upright exercises in patients with ischaemic heart disease was tested. Five short term exercises (4--8 min) with continuous load increase and with 30 min rest intervals between tests were used. No tendency to change was found concerning work time to appearance of angina (APT), maximal working time (MWT) or time for disappearance of angina after exercise (DPT). The coefficient of variation was low for APT and MWT but considerably higher for DPT, being 9, 5 and 27%, respectively. MWT was considered as the end-point of choice. The ST depression at MWT showed no tendency to change and the variation was moderate (14%), while at APT and DPT the variation was high (52%), but, likewise, with no tendency to change. The maximal heart rate increased slightly and significantly (P less than 0.001), while the maximal blood pressure was constant throughout tests, thus the maximal rate pressure product tended to increase. This indicates a slight improvement of the myocardial performance at serial exercises, which, however, does not affect the reproducibility of the anginal reaction.
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PMID:Reproducibility of work performance at serial exercises in patients with angina pectoris. 74 Dec 3

Variant angina pectoris, usually not precipitated by exertion or emotional stress, often is more severe and lasts longer than classic angina. The pain tends to recur at about the same time each day. Arrhythmias, usually ventricular, occur in about 50% of cases during the peak of pain. Electrocardiograms show a characteristic ST segment elevation during pain, which is in contrast to the ST segment depression of classic angina pectoris. Pain may be due, at least in some cases, to a temporary increase in tonus of a single, large, narrowed coronary artery. Chemical changes in the myocardium and plasma catecholamine changes differ from those occurring in classic angina pectoris. The course of the disease is highly variable but the prognosis must be regarded as grave, since single large vessel disease, present in most cases, is associated with severe myocardial ischemia. Patients with variant angina pectoris should be studied early with coronary arteriography and considered for coronary artery bypass surgery if appropriate.
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PMID:The variant form of angina pectoris. 76 70

Under observation were kept 80 patients with signs pointing to the sick sinus syndrome. Most of them suffered from ischemic heart disease, from atherosclerotic cardiosclerosis and acute myocardial infarction. Persistent sinus bradycardia with active and passive heterotopic arrhythmias were recorded in 42 patients. Sino-auricular block of the II and III degrees or asystolia of the atria with ectopic arrhythmias were observed in 37 cases. A number of patients displayed fibrillary bradyarrhythmia, extrasystole with post-extrasystolic depression of the rhythm and other disturbances. The so-called tachycardia-bradycardia syndrome characterized by the presence of tachycardiac arrhythmias occurring against the background of a marked bradycardia was registered in 25 persons. Fifteen patients demonstrated attackes of the Morgagni-Adams-Stokes syndrome, usually associated with lengthy periods of cardiac asystole. The treatment of ectopic arrhythmias in patients with the sick sinus syndrome presents considerable difficulties, but in many of them these disorders could be successfully eliminated by a careful and rigidly controlled application of antiarrhythmic agents (isoptin, ajmalin, pulsnorma, rhythmodan, beta-adrenergical blocking agents). For some patients exhibiting a tendency toward asystole electric stimulation of the heart is indicated.
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PMID:[Syndrome of sino-atrial node asthenia]. 79 80

Twenty patients with ischemic heart disease documented by coronary angiograms or ST segment depression in the ECG during treadmill walking, were administered sublingual nitroglycerin 0.3 to 0.6 mg on one occasion and a chewable form of isosorbide dinitrate 5 mg on another occasion during treadmill walking when anginal discomfort was definitely present at a mild degree of intensity. Despite continued walking at a constant speed and grade, angina was relieved in all patients, completely in most patients, partially in a few. The average time from administration of the medication to onset to relief was 74.7 seconds for nitroglycerin and 107.6 seconds for chewable isosorbide dinitrate. Average time to complete relief or maximal incomplete relief was 190.3 seconds for nitroglycerin and 315.1 seconds for chewable isosorbide dinitrate. Ischemic electrocardiographic changes were reverted toward normal by nitroglycerin in 13 subjects and by isosorbide dinitrate in 15. The differences in onset to complete relief were all statistically significant indicating that nitroglycerin is more rapid in its action than is chewable isosorbide dinitrate.
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PMID:Effectiveness of isosorbide dinitrate and nitroglycerin in relieving angina pectoris during uninterrupted exercise. 80 37


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