Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Catecholamine cardiomyopathy (CM) was produced in rabbits by a 90-min infusion of norepinephrine (NE, 2 micrograms . kg-1 . min-1). Left ventricular (LV) contractility and pump function (VF) were examined 2 days later and compared with control animals. The effects of hypercapnia [CO2 tension (PCO2) greater than 70 mmHg] and inotropic responsiveness to NE were also determined. VF was assessed by means of left ventricular function curves obtained with constant aortic pressure and heart rate and quantified by determining stroke volume at left ventricular end-diastolic pressure of 10 cmH2O (SV10). Mean SV10 was 1.16 +/- 0.06 ml in controls but averaged only 0.93 +/- 0.05 in CM (P less than 0.02). Hypercapnia caused significantly greater depression of VF in CM than in controls. NE dose-response curves demonstrated increases in both LV dP/dtmax and SV10 in each group. The percent increase in LV dP/dtmax was markedly attenuated n CM, but the increments in SV10 did not differ. The mean histological score in the CM animals was 1.6 +/- 0.1, indicating extensive myofiber injury. No histological abnormalities were observed in the controls. Thus functional defects correlated with the presence of histopathological changes. In addition, a dissociation of velocity (dP/dtmax) and force (SV10) responsiveness to inotropic stimulation was identified in the CM group.
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PMID:Ventricular function in norepinephrine-induced cardiomyopathic rabbits. 706 51

Myocardial scintigraphy with thallium-201 and electrocardiogram-gated left ventriculography with technetium-99m labelled red blood cells were applied in four groups of subjects: 25 with no signs or symptoms of cardiovascular disease (group 1), 28 with a "false" positive exercise electrocardiogram (group 2), 14 with angina pectoris and normal coronary angiograms (group 3), and 43 with angina pectoris and fixed coronary artery stenoses (group 4). In groups 1 and 4 the radionuclide findings were in accordance with clinical and invasive measurements. In groups 2 and 3 the most important finding was the lack of increase in left ventricular ejection fraction during exercise in about half of these subjects (even a decrease in 25%), indicating subnormal myocardial reserve. The additional finding of pathological myocardial biopsies in four of these patients suggests that asymptomatic ST depression in patients with normal coronary angiograms may in some cases represent an early, preclinical sign of cardiomyopathy.
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PMID:Routine radionuclide techniques in evaluation of patients with suspected coronary heart disease. 710 18

Mucocutaneous lymph node syndrome (MCLS) in the young has been known to have coronary aneurysms, and then it has been recently suspected as a cause of premature atherosclerosis and cardiomyopathy. Thirty-three schoolchildren who suffered from MCLS were studied to evaluate cardiac involvements and left ventricular function using two-dimensional (2-D) echocardiograms and submaximal stress test. Fifteen normal schoolchildren were studied as normal control. All these MCLS children were asymptomatic and had no significant findings in routine chest X-ray and electrocardiographic examinations. According to submaximal stress test, 8 cases showed a J type ST depression of only 0.5--1.0 mm, and there were no positive cases. Using 2-D echocardiograms, the left coronary artery was detected in 85% and the right coronary in 27%. One case showed an aneurysm of the left coronary artery. However, none of them showed abnormal left ventricular wall motion or the wall motion abnormality compatible with cardiomyopathy. There were no significant differences between MCLS and normal control in ejection fraction, mean VCF, diastolic descent rate of the anterior mitral valve, D/S ratio of the left ventricular wall, and Weissler's index (PEP/ET). These findings suggested that 1) most of MCLS schoolchildren do not have obvious cardiac involvement and their left ventricular function is within normal limits, 2) because of its low sensitivity, submaximal stress test is not so useful in screening coronary lesions, and 3) the 2-D echocardiogram works not only in detecting coronary aneurysms but also in evaluating left ventricular function.
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PMID:[Noninvasive evaluation of cardiac involvements and left ventricular function in schoolchildren with the history of mucocutaneous lymph node syndrome]. 711 88

Round heart disease and ascites were induced in 8-day-old turkey poults by administering 0.75% sodium chloride in distilled water. Clinical signs included increased water consumption, loose feces, depression, and increased respiratory rate. Mortality was noticed after 3 days on the saline solution. Light microscopic and electron microscopic studies were made on the right and left free cardiac ventricular walls. Massive glycogen accumulations were demonstrated by periodic acid-Schiff staining and malt diastase digestion. Electron microscopic studies further showed the presence of extensive intrafibrillar glycogen, myofibrillar disarray, lysis of myofilaments, Z-band streaming, and disruption of intercalated discs. These changes are consistent with congestive heart failure and are similar to furazolidone-induced cardiomyopathy. A mechanism is suggested whereby sodium ions may cause hypertension and also act directly to influence the electrical and contractile activity of the heart muscle.
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PMID:Ultrastructural changes of sodium chloride-induced cardiomyopathy in turkey poults. 715 22

Multistage treadmill stress testing was performed in 24 patients with idiopathic cardiomyopathy using Bruce protocol. 5 patients were considered to have hypertrophic obstructive cardiomyopathy (HOCM), 12 hypertrophic nonobstructive cardiomyopathy (HCM) and 7 congestive cardiomyopathy (CCM). Heart rate, systemic blood pressure, electrocardiographic changes and exercise tolerance were observed. The effect of propranolol on exercise tolerance was investigated in HOCM and HCM. 1) Exercise duration was less in patients with HCM and HOCM than in normal subjects (50 subjects) and greater than in 50 anginal patients. In CCM, exercise duration was the least. 2) Electrocardiographic changes observed in HCM and HOCM were increase of T waves and lessening of ST depression. In CCM, appearance of ventricular arrhythmia was noted in 4 of 7 patients. 3) Maximam exercise tolerance was reached at Bruce state III-IV in HOCM, stage III in HCM and stage II in CCM. 4) Propranolol administration resulted in improvement of exercise tolerance in 3 of 7 patients with HOCM and HCM.
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PMID:[Treadmill exercise testing in patients with idiopathic cardiomyopathy (author's transl)]. 719 Sep 56

To clarify the pathogenesis of chest pain in patients with cardiomyopathies, we compared coronary blood flow and other indicators of ischemia at rest and during pacing-induced tachycardia in nine patients with cardiomyopathy (four hypertrophic and five congestive) and in five control subjects. Coronary blood flow was reduced at rest and during pacing in cardiomyopathy patients compared with controls. In patients with hypertrophic cardiomyopathy, pacing induced chest pain in all, increased ST-segment depression in three patients and increased coronary venous lactate concentration. With pacing, two of five patients with congestive cardiomyopathy had chest discomfort and three had increased ST-segment depression, but coronary venous lactate concentration did not change significantly. In both groups of cardiomyopathies, the ratio of the systolic and diastolic pressure-time indexes tended to decrease more than in controls during pacing. Thus, myocardial perfusion is decreased in patients with cardiomyopathy, both at rest and during pacing. The changes detected during pacing point to subendocardial ischemia as the likely mechanism for angina in hypertrophic and possibly also in congestive cardiomyopathy.
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PMID:Pathophysiology of chest pain in patients with cardiomyopathies and normal coronary arteries. 719 3

Exercise tests were performed on 50 patients with hypertrophic obstructive cardiomyopathy (HOCM) and 19 patients with hypertrophic nonobstructive cardiomyopathy (HNCM) of NYHA classes I to IV, and on 16 patients with congestive cardiomyopathy (CCM) of NYHA classes III and IV as well as, for detection of latent cardiomyopathy (LCM), i.e. functional impairment during exercise with normal findings at rest, on 102 patients with typical or atypical angina pectoris and ECG abnormalities of unknown etiology (left bundle branch block or ST segment depression) but normal coronary arteries and normal left and right ventriculogram. Measurements included heart rate, stroke volume, cardiac output, pulmonary artery pressure and minimal cardiac transit times of Indium-113m. Furthermore, in a large number of patients with latent cardiomyopathy, thallium-201 myocardial imaging and measurements of myocardial lactate extraction during high-rate atrial pacing were performed. The findings suggest that 1. the functional classification based on the patients' complaints often differs from the grade of hemodynamic impairment detected by exercise testing, 2. therapeutic effects (propranolol or surgery in HOCM, prazosin in CCM) are more pronounced under exercise as compared with resting conditions. Latent cardiomyopathy can be diagnosed only by detection of impaired function during exercise (increased pulmonary artery pressure, impaired myocardial lactate extraction during high-rate stimulation), since ventricular function and hemodynamics are normal at rest.
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PMID:[Exercise studies in patients with cardiomyopathy (author's transl)]. 720 Sep 43

Inotropic responsiveness to norepinephrine (NE) or Ca2+ was studied in 15 rabbits with catecholamine cardiomyopathy (CM) and the results were compared with 11 controls. The former group was prepared by infusing NE (2 micrograms/min/kg) for 90 minutes, 2 to 3 days prior to study, and injury was confirmed and quantified histologically. Comparison of NE dose-response curves relating percent increase of left ventricular (LV) dP/dt max to NE dose in six controls and 10 CM hearts revealed significant depression of CM contractility. Responses to graded infusions of Ca2+ were also determined in five controls and in five CM animals. With the increases in serum Ca2+ identical in the two groups, the percent increases in dP/dt max were less in CM hearts. Further, NE dose-response curves obtained during continuous CaCl2 infusion were sharply attenuated in CM hearts and initial LV end-diastolic pressure (LVEDP) in the CM hearts was considerably higher than in the controls. It is concluded that inotropic sensitivity to NE is reduced in CM hearts. This cannot be ascribed to altered beta-receptors alone, because responsiveness to Ca2+ was also reduced. Myocardial damage was indicated by histology and elevated LVEDP. Moreover, the normalized percent data suggest tht the remaining viable fibers in the CM hearts were functioning subnormally and thus reduced performance was not due solely to the decreased number of contracting units.
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PMID:Inotropic responsiveness of the heart in catecholamine cardiomyopathy. 745 36

To test the feasibility of detecting transient left ventricular regional wall motion abnormalities during exercise-induced myocardial ischemia, 55 patients undergoing diagnostic coronary arteriography were studied in a prospective blinded manner with wide angle cross-sectional echocardiography. The ultrasonic studies were obtained with the patients at rest and during exercise in the supine position using a bicycle ergometer. Cross-sectional echocardiographic studies during exercise were adequate for analysis in 43 (78 percent) of the 55 patients. Forty-one of the 43 manifested either a new regional wall motion abnormality during exercise (20 subjects) or wall motion that remained entirely normal during exercise (21 subjects); in two subjects an abnormal wall motion abnormality at rest did not change with exercise. Nineteen of the 20 patients with a new regional wall motion abnormality had significant coronary artery disease and 15 of these 19 had S-T segment depression during bicycle ergometry. The one patient with a normal coronary arteriogram had an early cardiomyopathy. Ten of the 21 subjects with normal wall motion at rest and during exercise had a normal coronary arteriogram, whereas 11 had evidence of important anatomic coronary artery disease and thus had a false negative echocardiographic findings. Six of these 11 patients had S-T segment depression during exercise. The usefulness of exercise echocardiography to predict coronary artery disease was not altered even when only 26 patients without previous myocardial infarction and with a normal cross-sectional echocardiogram at rest were considered. Thus, new regional wall motion abnormalities during exercise as identified with cross-sectional echocardiography represent a specific finding for the presence of coronary artery disease. However, normal regional wall motion during exercise does not exclude the presence of important anatomic coronary artery disease.
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PMID:Exercise cross-sectional echocardiographic diagnosis of coronary artery disease. 745 3

We studied the effects of 6-week treatment with nifedipine (35 mg/kg/day orally, p.o.) on streptozotocin (STZ)-induced diabetic rats. Injection of STZ [45 mg/kg intravenously, (i.v.) single dose] produced a significant increase in blood pressure (BP), bradycardia, hyperglycemia, hypoinsulinemia, hyperlipidemia, hypothyroidism, depression in left ventricular developed pressure (LVDP), cardiomyopathy, and nephropathy. Treatment of diabetic rats with nifedipine normalized the BP and prevented bradycardia. Insulin levels were decreased after nifedipine treatment in diabetic as well as nondiabetic rats. However, serum glucose levels were also partially decreased in diabetic animals by nifedipine treatment. In control animals as well, glucose levels were in the normal range despite lower insulin levels observed after nifedipine treatment. Nifedipine treatment significantly prevented STZ-induced increase in cholesterol and triglyceride levels. Nifedipine treatment significantly prevented STZ-induced hypothyroidism and also prevented STZ-induced cardiac depression and cardiomyopathy. Our data indicate that nifedipine increases insulin sensitivity and has some beneficial effects on cardiovascular parameters. It may therefore be considered a preferred drug in the treatment of hypertension associated with diabetes mellitus.
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PMID:Effects of chronic nifedipine treatment on streptozotocin-induced diabetic rats. 756 66


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