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

Left ventricular (LV) myocardial function and the influence on LV pump performance of associated coronary arterial disease, of outflow obstruction and its consequences, and of altered ventricular pressure-volume characteristics were examined in a representative group of 28 adult patients with symptomatic severe aortic stenosis (valvular orifice area less than 0.50 sq cm/sq m). Eighteen patients (64%) exhibited depressed LV pump performance with levels of ejection fraction less than 0.50. In seven patients, coronary arterial disease documented by either arteriographic studies or postmortem analyses was associated with a segmental (i.e., nonhomogeneous) LV contractile disorder consistent with previous myocardial infarction. In the remaining 11 patients a homogeneous LV contractile disorder was the result of chronic outflow obstruction and its consequences. The possibility that reduced ventricular performance might be accounted for by increased afterload could not be supported by significant correlation between LV contractile characteristics (estimated from the ejection fraction and the mean circumferential fiber shortening rate) and indices of afterload (including LV systolic pressure, aortic valvular orifice area, and mean systolic wall tension). This observation suggested that myocardial hypertrophy and other consequences of longstanding obstruction to outflow played a primary role in depression of LV performance in these patients. Left ventricular end-diastolic volume was abnormal in all but three patients with depressed LV function; this increase was accompanied by a disproportionately greater increment in end-diastolic pressure, suggesting that reduced distensibility limited the ability of the ventricle to compensate for reduced contractile performance by means of the Starling mechanism.
 ...
PMID:Determinants of cardiac performance in severe aortic stenosis. 12 19

We report the clinical and laboratory effects of continuous-flow plasma exchange in two patients suffering from homozygous familial hypercholesterolemia. In one (Case 1) plasmapheresis was performed at fortnightly intervals over a period of 18 months; in the other (Case 2) the necessity for surgical relief of an associated supravalvular aortic stenosis resulted in premature termination of the trial. The plasma cholesterol levels in both patients fell by 35 per cent from the mean before study in the course of treatment. In Case 1 this was associated with marked regression of the patient's xanthomas, disappearance of the S-T segment depression seen on effort electrocardiograms obtained prior to the introduction of plasmapheresis, possible widening of the stenosis present at the origin of the left anterior descending coronary artery, and a marked increase in exercise tolerance and diminished frequency of anginal attacks. Cessation of cholestyramine and clofibrate administration during this study did not in any way reverse the reduction of plasma cholesterol achieved by means of plasmapheresis combined with drug therapy. We conclude that plasmapheresis has a role to play in the management of patients with homozygous familial hypercholesterolemia.
 ...
PMID:Continuous flow plasma exchange in the treatment of homozygous familial hypercholesterolemia. 21 Jun 64

1) In "left-sided" cardiac diseases, the effects of nitroglycerin on arterial pressure and heart rate were noted to be modest and disappeared within 15 minutes whereas the effect upon venous pressure, measured on the median cubital vein, lasted for approximately 30 minutes. 2) At 30 minutes after a dose of nitroglycerin there occured a significant depression of venous pressure elevation on exertion in patients with such "left-sided" cardiac diseases as ischemic heart disease, arteriosclerotic heart disease and hypertensive cardiovascular disorder. In patients with mitral insufficiency and aortic stenosis, on the other hand, the exertional venous pressure elevation was significantly suppressed 7 minutes after nitroglycerin although the suppression did not longer exist 30 minutes after administration. 3) The arterial pressure, heart rate, resting venous pressure and venous pressure elevation on exertion were virtually not affected by the administration of nitroglycerin in "right- or both-sided" cardiac disorders. 4) There was no significant change in cardiac output 30 minutes after a sublingual dose of nitroglycerin. The data obtained seem to stress importance of the effect of dilating capacitance vessels in the mechanism of antianginal action of nitroglycerin.
 ...
PMID:[Effect of nitroglycerin on peripheral venous pressure at rest and during exercise in patients with heart diseases (author's transl)]. 40 92

The diagnostic accuracy of the dipyridamole test in provoking coronary insufficiency was investigated in 79 patients with chest pain and the results were compared with the findings on angiography and exercise electrocardiogram. 58 patients had documented severe coronary artery stenosis, 21 had patent coronary vessels (cardiomyopathy 8, aortic stenosis 1, ectopic origin of coronary artery 1, normal 11). Anginal pain after dipyridamole was a non-specific finding. Approximately half the subjects in whom coronary insufficiency would be expected according to the coronary angiographic and ventriculographic findings evidenced ischaemic ST-segment depression after dipyridamole, which was comparable to the number of positive exercise electrocardiograms. In 23 patients, most of whom had shown an inadequate frequency response during the initial exercise test, ergometry was repeated after the administration of dipyridamole. This resulted in an increase in ischaemic ECG response from 26 to 70%. It is concluded that a stress test combining dipyridamole and submaximum exercise increases the incidence of ischaemic ST-segment depression in comparison with ergometry alone. Anginal pain without ST-segment depression proved to be without diagnostic value.
 ...
PMID:[The diagnostic accuracy of the dipyridamole test in coronary heart disease (author's transl)]. 46 46

Cardiac arrest developed in two patients after the administration of oral potassium. Neither patient had renal insufficiency, but both had underlying heart disease. In one patient fatal ventricular fibrillation developed 4 days after he received an aortic valve replacement for aortic stenosis and while he was receiving oral potassium supplements. The serum potassium level before cardiac arrest was 8.1 meq. The second patient had angina and was given 40 meq of potassium orally 15 minutes after an exercise test which produced chest pain and S-T segment depression. One hour later, ventricular fibrillation developed. Resuscitation was successful. Both patients had electrocardiographic evidence of hyperkalemia. Oral administration of potassium may produce severe cardiac toxicity in patients with heart disease even when renal function is clinically normal.
 ...
PMID:Cardiac arrest due to oral potassium administration. 111 63

The incidence of positive submaximal treadmill exercise tests was evaluated in patients with mitral stenosis and aortic stenosis, no electrocardiographic evidence of left ventricular hypertrophy, and normal coronary arteries on angiography. Seven of 19 patients (37 percent) with aortic stenosis (53 to 80 mm Hg gradient across the aortic valve) had greater than or equal to 1.0 mm of ischemic S-T segment depression during or after a submaximal treadmill test. Three of 15 patients (20 percent) with mitral stenosis (11 to 22 mm Hg mean gradient across the mitral valve) had greater than or equal to 1.0 mm of ischemic S-T segment depression during or after a submaximal treadmill exercise test. Patients with significant valvular disease, no electrocardiographic evidence of left ventricular hypertrophy, and normal coronary arteries may have a positive submaximal treadmill exercise test due to an unfavorable balance between myocardial oxygen supply and myocardial oxygen demand.
 ...
PMID:Treadmill exercise test in aortic stenosis and mitral stenosis. 117 8

The relationship of exercise-induced electrocardiographic changes to severity of obstruction in congenital aortic stenosis was studied in 44 children. Twelve subjects, with ST segment depression of 1 mm or more lasting 0.08 seconds after the J Point, had left ventricular-aortic peak systolic pressure differences (gradients) ranging from 54 to 112 mm Hg. The remaining 32 children had less than 1 mm or no ST segment depression. Thirty-one of these had gradients ranging from 10 to 48 mm Hg and one had a gradient of 52 mm Hg. Vectorcardiograms, electrocardiograms, and chest roentgenograms were not useful in the identification of the severity of the lesion. The study suggests that children with severe gradients develop electrocardiographic ST segment changes with exercise, thereby helping to select those patients who should have catheterization studies to delineate the severity of the lesion. In those with a normal exercise test, cardiac catheterization may be safely delayed, but the exercise test should be repeated to identify those who develop progressive obstruction.
 ...
PMID:Exercise-induced electrocardiographic changes in children with congenital aortic stenosis. 118 36

Between 1978 and 1987, 1270 patients who survived single aortic or mitral valve replacement at the Rehabilitation Center in Bad Krozingen, Germany, underwent a comprehensive rehabilitation program. The preoperative diagnosis was isolated aortic stenosis in 425, isolated aortic regurgitation in 159, mixed aortic lesion in 211, isolated mitral stenosis in 208, isolated mitral insufficiency in 137 and mixed mitral lesion in 130 cases. Follow up examinations were carried out one and six months after surgery, and at yearly intervals thereafter. Exercise testing was performed with an electrically braked bicycle ergometer in the supine position, and the load was increased by 25 or 50 watts every two minutes until fatigue, severe angina, more than 0.3 mV ST-segment depression, or 80% of the age predicted maximum heart rate was achieved. Patients after aortic valve replacement had a better exercise performance one month after operation than did those after mitral valve replacement. Those with mitral stenosis showed more severe impairment of exercise tolerance than did the mitral insufficiency group. There was a steady increase in exercise tolerance between one and six months postoperatively, both in patients with aortic and those with mitral valve replacement, but the difference in performance between the two groups was still present (72% versus 57% of normal). The results of univariate and multivariate analyses showed that the preoperative employment status was the most important factor for postoperative return to work, followed by gender (male > female), exercise tolerance and valualar lesion (aortic > mitral).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Exercise tolerance and working capacity after valve replacement. 134 26

The aim of our studies was to estimate the relation between the reduction of the subendocardial blood flow, expressed by DPTI/TTI ratio and the grade of aortic stenosis determined by the maximal systolic aortic gradient. Additionally the influence of subendocardial blood flow reduction of left ventricular function and ECG alterations was assessed. The analyzed data were obtained during the cardiac catheterizations in a group of 30 patients (average age 32 years). The mean value of DPTI/TTI ratio was decreased (0.49 +/- 0.2) and associated with the elevated mean value of AGmax (72.2 +/- 38.1 mmHg). Negative correlation between DPTI/TTI and AGmax (r = -0.73; p less than 0.003), DPTI/TTI and LVEDP (r = -0.53; p less than 0.005) occurred. Depression of ST-T segment in EEG and episodes of anginal pain accompanied the reduction of subendocardial blood flow. We concluded that reduction in subendocardial blood flow in patients with SA-may lead subendocardial ischaemia of the left ventricular wall with subsequent of its function.
 ...
PMID:[Subendocardial blood flow index in relation to selected parameters of left-ventricular function in patients with aortic valve stenosis]. 143 98

The cause of the syncope in aortic stenosis has been the subject of controversy partly because only a few patients have been monitored during their syncopal episodes. Among the mechanisms proposed are hypersensitive carotid sinus, complete A-V block, ventricular arrhythmias, and ischemic myocardial depression. It is now accepted that the syncope is caused by a vasodepressor response from stimulation of left ventricular baroceptors, resulting in reflex hypotension and bradycardia. This case report describes a patient who developed a syncopal episode during stress testing. Although the mechanism for the syncope is consistent with the vasodepressor response, ischemic changes were observed in the electrocardiogram before the development of syncope. Review of literature shows that, although different mechanisms for syncope have been described, all reported patients manifested myocardial ischemia before the development of their syncopal episodes even when the syncope was nonexertional and clearly caused by a vasodepressor response. The authors conclude that, independent of the mechanism proposed, myocardial ischemia is overlooked as an important substrate in which the syncopes are precipitated in aortic stenosis.
 ...
PMID:Case report: myocardial ischemia: an overlooked substrate in syncope of aortic stenosis. 153 5


1 2 3 4 5 6 7 8 Next >>