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)

Overt cardiac failure usually presents with constant clinical features as consequences of the reduced pump action, associated with an increased adrenergic drive, independent of the underlying disease. However, the study of left ventricular function, before and during the phase of cardiac insufficiency, shows that different pathophysiological mechanisms are responsible for the symptoms and signs of reduced cardiac action. It is possible to recognize that cardiac failure is caused primarily by: (1) early severe depression of the inotropic state, i.e. dilated cardiomyopathies; (2) late inadequate level of ventricular hypertrophy, with normal contractility, i.e. aortic stenosis; (3) early inadequate level of hypertrophy and slightly reduced inotropic state, i.e. mitral insufficiency, and (4) late inadequate level of hypertrophy and severe progressive reduction in contractility, i.e. aortic insufficiency. The possibility of an 'in vivo' assessment of the different determinant parameters of left ventricular function (contractility, afterload, preload, fiber and chamber compliance) through echocardiography enables a better understanding of the mechanisms leading to the cardiac failure and a more efficient therapeutic approach.
 ...
PMID:Myocardial function in heart failure. 306 19

To evaluate the influences of transient myocardial ischemia on transmitral blood flow velocity patterns, pulsed Doppler echocardiography was performed during coronary artery occlusion in 10 anesthetized open-chest dogs, and also during esophageal pacing or the administration of dipyridamole in 79 patients with coronary artery disease (CAD), and in 19 control subjects. During occlusion of the coronary artery, an abrupt decrease in the peak velocity of the rapid filling wave (R) was noted within one min simultaneously with rapid decrease of % wall thickening in the ischemic regions. The peak velocity of atrial filling was augmented compensatorily. Although the transmitral blood flow velocity pattern did not change in the controls with esophageal pacing, changes similar to those which were obtained during experimental studies were demonstrated in CAD patients. There were no significant differences between transmitral blood flow velocity patterns of patients with multivessel disease and those with single vessel disease. Ischemic changes in transmitral blood flow velocity patterns were not demonstrated in patients with mitral regurgitation. Sublingual nitroglycerin normalized post-pacing abnormal blood flow velocity patterns. In contrast, after the intravenous administration of 0.56 mg/kg of dipyridamole, R and A were increased and the A/R ratio was unchanged both in CAD patients and the control groups. Deceleration time, or the half time, was prolonged during both provocation tests in CAD patients, and these changes were transient and were restored within several min. Furthermore, they were noted more frequently than was the development of ST depression on ECG, or chest pain. These findings indicate that the transmitral blood flow velocity patterns obtained by pulsed Doppler echocardiography are useful for detecting transient myocardial ischemia, though they have limitations in diagnosing the extent of coronary artery disease.
 ...
PMID:[Transmitral blood flow velocity patterns evaluated by pulsed Doppler echocardiography in diagnosing transient myocardial ischemia]. 314 32

ACBGS is indicated in patients with stable angina who have left main coronary artery disease; three-vessel disease; three or four of the clinical variables set forth in the Veterans Administration Cooperative Study; obstruction in proximal third of left anterior descending coronary artery as part of two- or three-vessel disease; and two- or three-vessel disease and exercise-induced ischemic ST-segment depression greater than or equal to 1.5 mm. ACBGS may increase survival in patients with limited exercise capacity. Finally, ACBGS may be indicated to increase the quality of life in patients with disabling angina that is refractory to medical treatment. Patients with unstable angina who have an inadequate response to intensive medical therapy should have emergency ACBGS. Indications for elective ACBGS in patients with unstable angina who respond adequately to medical therapy are the same as those for stable angina. Patients with rupture of the ventricular septum, acute severe mitral regurgitation, and cardiogenic shock with vessels suitable for ACBGS should have urgent ACBGS after acute myocardial infarction. Patients with postinfarction angina after the first few days following acute myocardial infarction, especially non-Q-wave infarction, should be considered for ACBGS. Indications for elective ACBGS in postinfarction patients are the same as those in stable angina. Patients with coronary artery disease, especially those with a significant amount of ischemic myocardium, who must undergo cardiac surgery for valvular heart disease or for congenital heart disease should probably have ACBGS performed at the time of surgery.
 ...
PMID:Indications for coronary artery bypass graft surgery. 331 16

Inferolateral ST depression, T wave inversion, and QT prolongation have been frequently described in reports of largely symptomatic mitral valve prolapse (MVP) patients, but not in a recent population-based survey of mainly asymptomatic subjects with MVP. To learn if there is a relationship between these ECG changes and symptoms, physical findings or hemodynamic sequelae, we reviewed ECGs from 119 patients, ages 18 to 60 years who had MVP diagnosed by echocardiography. Seventy-four percent had symptoms characteristic of MVP. ST-T changes were found as frequently in asymptomatic patients (29%) as in those symptomatic (27%), and did not identify those with hemodynamic sequelae of MVP (apical systolic murmurs, Doppler-defined mitral regurgitation, or left atrial enlargement). QT prolongation was found more frequently in the symptomatic group (25% vs 10%) but did not predict syncope. When compared to the expected 0.9% prevalence of ST abnormalities in a normal population, ST-T changes and QT prolongation are indeed frequent in MVP, but are not useful in identifying clinically important subsets.
 ...
PMID:Repolarization abnormalities in mitral valve prolapse. 359 11

Determination of the optimal time for surgical intervention in chronic mitral regurgitation has remained controversial. There are similarly important factors in favor of temporizing with medical treatment alone as there are in support of relatively early surgery (Table 1). Since rheumatic valvulitis may play a subordinate role, in contrast to etiologies such as myxomatous degeneration of the mitral valve, rupture of chordae tendineae, papillary muscle dysfunction due to coronary artery disease and other causes, left ventricular function is generally determined by the adaptations of the myocardium to the volume overload, or to ischemia or infarction from coronary artery disease rather than to a concomitant myocarditis. Based on actuarial survival curves in symptomatic patients with combined mitral regurgitation and stenosis or mitral regurgitation alone, it can be assumed that surgery can result in improved survival, in particular if a reconstructive mitral valve procedure rather than prosthetic valve replacement is performed. Medical treatment is carried out with digitalis to enhance myocardial contractility, diuretics and vasodilators to reduce pre- and afterload with resultant diminished effective mitral orifice area and regurgitant volume, lowering of pulmonary artery and pulmonary venous pressures and an increase in systemic cardiac output. Presently, however, there is no convincing evidence that symptom-status is improved or the natural history favorably affected over a number of years. For assessment of left ventricular myocardial function the end-systolic pressure/volume or the end-systolic stress/volume index appear preferable. Values of the latter less than or equal to 2.2 are associated with increased postoperative mortality and improbable improvement in functional status. Additionally, patients with an ejection fraction less than 40% or end-diastolic volume greater than 140 ml/m2 as well as those with end-diastolic dimension greater than 8 cm or end-systolic dimension greater than 5.5 cm have less favorable postoperative survival or further deterioration in ventricular function. Impaired right ventricular function secondary to the increased afterload imposed by pulmonary hypertension generally can be normalized postoperatively. Depression of right ventricular myocardial contractility is not, however, a common pathophysiologic feature in chronic mitral regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Timing of surgical intervention in chronic mitral regurgitation. 369 75

In patients with valvar heart disease detection of coronary artery disease by conventional non-invasive methods may be difficult. The usefulness of thallium-201 exercise scintigraphy for detecting coronary artery disease was evaluated in 16 patients with aortic stenosis, 17 with aortic regurgitation, nine with mitral stenosis, and six with mitral regurgitation who were investigated by coronary angiography. Only two of 21 patients with greater than or equal to 50% coronary artery obstruction had normal thallium images. Three patients without angiographic evidence of coronary artery stenoses had perfusion defects demonstrated by thallium scintigraphy. Only one patient with greater than or equal to 75% coronary stenosis had a normal thallium scan. Angina pectoris or ST segment depression evoked by exercise test were not useful in distinguishing patients with coronary artery disease from those with normal coronary vessels. These data suggest that thallium exercise scintigraphy may be a useful non-invasive test for detecting coronary artery disease in patients with valvar heart disease.
 ...
PMID:Detection of coronary artery disease by thallium scintigraphy in patients with valvar heart disease. 373 Feb 15

Episodic mitral regurgitation due to ischaemia of one or both papillary muscles was studied in a review of 39 cases with complementary investigations and compared with previously reported data. The condition occurred after myocardial infarction in 69 p. 100 of cases (usually after inferior infarction: 54 p. 100) associated with ischaemia of the controlateral territory; there was no history of myocardial infarction in 31 p. 100 of cases. The patients were usually elderly (73 years), often hypertensive (77 p. 100) and diabetic (62 p. 100). The clinical syndrome was that of severe anginal pain, mitral regurgitation and left ventricular failure which was critical in some cases. The ECG showed typical ST depression (4.1 +/- 1.6 mm) especially in the antero-lateral leads; left bundle branch block (28 p. 100) with left axis deviation (18 p. 100), sometimes associated with changes of chronic infarction (64 p. 100) was also recorded. Mitral regurgitation and left ventricular failure regressed almost completely in typical cases between attacks, whilst the ECG showed slight residual sub-endocardial ischaemia (ST depression of 1.5 +/- 0.4 mm) in 30 cases and/or subepicardial ischaemia observed in the anterolateral leads in 13 cases. Phonomechanographic recordings (n = 32) showed moderate mitral regurgitation (1-2/6), usually parasystolic (47 p. 100) or early and mid systolic (36 p. 100) in 87.5 p. 100 of cases between attacks, aggravated by handgrip exercise and improved by trinitrin administration. Echocardiography (n = 27) only showed mitral valve changes in 2 patients (increased density of the papillary muscle in 1 case and prolapse of the anterior leaflet in 1 case); however, segmental wall hypokinetic (51 p. 100) or dyskinetic (15 p. 100) motion, was common with increased left ventricular end diastolic dimensions (mean 56.3 +/- 8.0 mm) and decreased fractional shortening (mean 0.30 +/- 0.07) (67 p. 100). Left atrial dimensions were increased (mean 39.7 +/- 6.4 mm) in 52 p. 100 of patients. Thallium 201 myocardial scintigraphy (n = 32) showed hypofixation in 57 (36 p. 100) and a lacuna in 23 (14 p. 100) of the 160 segments analysed. Left ventricular angioscintigraphy (n = 27; 135 segments) showed hypokinesia in 72 segments (53 p. 100); 2.7 segments per patient), akinesia in 19 segments (15 p. 100; 0.7 segment per patient) and dyskinesia in 2 segments (1.5 p. 100); 0.1 segment per patient). The global ejection fraction was 46 +/- 13 p. 100. Coronary angiography (n = 8) showed significant diffuse atherosclerosis.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:[Paroxysmal mitral insufficiency caused by ischemic dysfunction of the papillary muscles. Apropos of 39 cases]. 391 82

The usefulness of end-systolic measures of left ventricular performance as a load-independent method of assessing of ventricular contractility has been studied in intact, conscious dogs. The end-systolic pressure-chamber diameter (P-D) relation was shown to be linear, unaltered by preload changes, and shifted in a parallel fashion by inotropic stimulation, whereas the end-systolic pressure-volume relation appeared to increase in slope with increased contractility. A simplified measure of end-systolic relations that does not require measurement of chamber volume or diameter, the end-systolic pressure-wall thickness ( WTh ) relation, was also linear and shifted with acute changes in inotropic state. During regional ischemia, the regional end-systolic WTh relation also may provide a relatively load-independent means of detecting regional depression of myocardial contractility. With chronic pressure overload hypertrophy in dogs, the end-systolic P-D relation was markedly shifted upward and to the left, which indicates hyperfunction of the left ventricle; however, end-systolic wall stress-diameter relations were identical before and after the development of hypertrophy, which suggests that myocardial contractility was unaltered. These findings and clinical studies of mitral regurgitation imply that for assessing resting left ventricular contractility in certain chronic conditions, the use of wall stress rather than pressure may be appropriate in the end-systolic framework. Further experimental studies are needed in the intact circulation to better characterize end-systolic relations before their full potential in the clinical setting can be realized.
 ...
PMID:Applications and limitations of end-systolic measures of ventricular performance. 623 74

Poor effort tolerance is observed in a small percentage of cases of idiopathic mitral valve prolapse (IMVP). The aim of this study was to assess the possible left ventricular dysfunction in such cases, responsible for poor effort tolerance. Left ventricular function and segmental wall motion were studied retrospectively in a group of 17 patients with IMVP. The patients, average age 53 +/- 12 years, had poor effort tolerance (ST segment depression of 2 to 4 mm in 15 cases, drop in blood pressure in 6 cases) justifying catheter and angiographic studies. All patients had IMVP confirmed on RAO left ventriculography. There was no associated mitral regurgitation or coronary artery disease. Left ventricular function was studied by parameters of global function (systolic and diastolic parameters, volume measurements) and by a quantitative study of segmental wall contraction. The method used for studying regional wall motion was an application of the Stanford method in which segmental shortening is studied over all the endocavitary contour of the LV during an angiographic cycle filmed at 50 frames/second in the RAO projection. The time and velocity amplitudes of wall motion were measured during systole and diastole. The same methodology was applied to 21 normal control subjects. The results showed abnormal volumic compliance and wall motion in the IMVP group. Asynergy was mainly confined to the antero-lateral wall of the LV. The amplitude of contraction was generally normal but the contraction was slower and finished earlier. In the same zone, relaxation was abnormally early and lasted longer.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Left ventricular global and segmental function in pure mitral valve prolapse with poor tolerance for exertion]. 643 25

We investigated the clinical course of 57 patients with acute inferior myocardial infarction as regards anterior S-T segment depression. Thirty of them showed S-T segment depression greater than or equal to 0.15 mV in at least 2 precordial leads, and 27 did not exhibit such changes. Twenty-seven patients underwent post-infarction exercise stress test. Furthermore, coronary arteriographic findings and left ventricular performance were evaluated in 8 of these patients with and in 8 without anterior S-T segment depression. Patients with anterior S-T segment depression showed greater inferior S-T segment elevation on admission ECG and deeper Q wave in lead aVF in ECG tracings recorded 1 month later. Higher incidences of in-hospital angina (10/30 vs 2/27, P = 0.01) and of late development of cardiac failure (5/21 vs 0/19, P = 0.03) were found among patients with anterior S-T segment depression. They showed a higher overall coronary score (82.4 +/- 31.0 vs 32.5 +/- 28.9, P = 0.002) and left anterior descending artery score (44.1 +/- 20.7 vs 8.5 +/- 16.1, P = 0.0009) and a reduced ventricular performance, evaluated by ventriculography score (49.5 +/- 2.7 vs 51.8 +/- 2.4, P = 0.05). A higher incidence of mitral regurgitation, secondary to papillary muscle dysfunction, was also found among patients with anterior S-T segment depression (4/8 vs 0/8, P = 0.04). Furthermore, the degree of anterior S-T segment depression in each of these subjects was closely correlated with the corresponding difference from normal ventricular score (r = 0.86, P less than 0.01). Finally, no difference between the two groups of patients was found as to incidence of positive exercise stress tests.
 ...
PMID:Anterior S-T changes during acute inferior myocardial infarction. 664 77


<< Previous 1 2 3 4 5 Next >>