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At least 19 recordsLinked to original sources
PubMed1992

Hemodynamic observations following orthotopic cardiac transplantation: hemodynamic responses to upright exercise at 1 year.

Central hemodynamic responses during upright exercise were studied at 1 year in 40 orthotopic cardiac transplant recipients. Hemodynamic responses were characterized by slow rise in heart rate and blunted peak exercise heart rate response, a significant early increase in stroke index followed by a plateau phase, and a steady increase in ventricular filling pressures and pulmonary artery pressure. In spite of exclusive utilization of the Frank-Starling mechanism to augment cardiac output during early exercise, the pressure responses were comparable to those reported in normal subjects. Our observations also indicate that similarly to normal subjects, the heart rate response plays an important role in the cardiac output achieved at maximum exercise. Although patients with younger donor hearts achieved a more favorable maximum heart rate, the other hemodynamic parameters showed no correlation with the donor heart age. Thus, no hemodynamic disadvantage of older donor hearts could be demonstrated. These data provide further enlightenment regarding the mechanisms of the well-preserved functional capacity noted in these patients.

Adult↗
PubMed1978

Systemic and pulmonary hemodynamic effects of saralasin infusion in hypertension. Predictability of plasma renin status from hemodynamic changes.

Hemodynamic measurements were obtained before and after 30 minutes of saralasin infusion in 26 fasting adults with hypertension (25 men and 1 woman). Nine showed a depressor response with a decrease in mean intaarterial pressure greater than 20 mm Hg. Ten were nonresponders and seven had an agonistic response with an increase in mean arterial pressure of greater than 10 mm Hg. Heart rate, pulmonary arterial and wedge pressures and pulmonary vascular resistance were nearly identical in the three groups and remained unchanged. Cardiac index decreased from a mean of 2.76 +/- 0.14 (standard error of the mean) to 2.48 +/- 0.1 liters/min per m2 in the nonresponders (P less than 0.02) but remained unchanged in the groups with a depressor or an agonistic response. The mean systemic vascular resistance decreased from 2,406 +/- 303 to 1,839 +/- 265 dynes sec/cm5 in the group with a depressor response (P less than 0.001) and increased in nonresponders (less than 0.02) and those with an agonistic response (P less than 0.01). However, regardless of the response of mean arterial pressure, systemic vascular resistance decreased only in the 10 patients with a plasma renin activity greater than 5 ng/ml per hour (8 from the depressor response group and 1 each from the nonresponse and agonistic response groups). It is concluded that (1) classification based soley on the response of aterial pressure to saralasin ignores important hemodynamic changes; (2) the response of cardiac index--no change in the patients with a depressor response and a reduction in nonresponders--suggests that endogenous angiotension II supports cardiac output in these groups; (3) a decrease in systemic vascular resistance is better than a decrease in mean arteiral pressure as a predictor of the status of the plasma renin activity; and (4) lack of change in pulmonary vascular resistance suggests that endogenous angiotension II plays an insignificant role in maintaining the resistance of the pulmonary vasculature.

Adult↗
PubMed1992

Hemodynamic observations following orthotopic cardiac transplantation: evolution of rest hemodynamics in the first year.

The evolution of resting hemodynamics was studied at 1 week and 1 year in 40 patients following orthotopic cardiac transplantation. Abnormal hemodynamics after transplantation, characterized by elevated ventricular filling pressures (indicating diastolic dysfunction) and also by pulmonary hypertension, showed normalization by 1 year. In the absence of innervation, the resting heart rate of heart transplant recipients should theoretically be close to the intrinsic heart rate predicted by the age of the donor heart. In this study, a high incidence of relative sinus bradycardia (an indicator of sinus node dysfunction) was noted in the first post-operative week, although again there was a tendency to normalization by 1 year. These beneficial changes help to explain the dramatic and sustained improvement in the functional capacity of these patients late after transplantation.

Adult↗
PubMed1979

Hemodynamic patterns in human hepatic cirrhosis: a prospective randomized study of the hemodynamic sequelae of distal splenorenal (Warren) and mesocaval shunts.

Increasingly successful operative management of gastroesophageal variceal hemorrhage has been achieved by newer techniques of portal venous reconstruction. Although it is postulated that the clinical success may be due to more selectivity in portal venous shunting, direct determination of the effect of portasystemic shunt on portal vein blood flow has not been possible. Direct determinations of portal vein blood flow were performed preoperative on unanesthetized, hemodynamically stable cirrhotic patients by observation of radiopaque water-insoluble droplets. Patients were then randomized into elective distal splenorenal (Warren) or mesocaval shunt and determinations were performed postoperatively under similar conditions when clinically possible. Although portal vein blood flow was not significantly different before (929 +/- 147 ml/min) or after 899 +/- 271 ml/min) distal splenorenal shunt, there was a large change in portal vein blood flow after mesocaval shunt, decreasing from 772 +/- 177 ml/min (hepatopetal) to -1021 +/- 310 ml/min (hepatofugal) p < 0.01). After either procedure total hepatic blood flow (as determined by cardiac green clearance) was not significantly changed, nor was renal blood flow; however, cardiac output was significantly increased after mesocaval shunt. Thus the theoretical hemodynamic goals of the selective distal splenorenal shunt, i.e., preservation of the hepatopetal flow within the portal vein, is achieved as determined in the early postoperative period. The correlation between these changes and the eventual clinical outcome remains to be determined.

Cardiac Output↗
PubMed1979

[Hemodynamics of the liver. II. Hemodynamics of the dog liver after resection of 70% of the liver and ligation of the left branch of the portal vein].

Blood supply to the liver was determined by help of the direct method after 70 per cent hepatic resection and after ligation of the left branch of portal vein in dogs. The total blood supply remains unchanged after both surgical procedures, while the circulation in the remaining lobes, resp. in those patent for portal blood stream, considerably increases. After the resection portal hypertension develops. This elevated portal pressure was not observed after ligation of the left portal branch.

Animals↗
PubMed1977

Correlative classification of clinical and hemodynamic function after acute myocardial infarction.

To characterize the relation between clinical and hemodynamic state in acute myocardial infarction, 200 patients with acute infarction were evaluated with clinical and hemodynamic criteria. Patients were classified clinically on the basis of peripheral hypoperfusion (hypotension, tachycardia, confusion, cyanosis, oliguria) and pulmonary congestion (rales, abnormal chest roentgenogram). Four clinical subsets were defined that correlated with cardiac index (Cl, liters/min per m2) and pulmonary capillary pressure (PCP, mm Hg): (see article). Parallel hemodynamic subsets were developed independently on the basis of depressed cardiac index (2.2 liters/min per m2 or less) and elevated pulmonary capillary pressure (greater than 18 mm Hg). The rate of accuracy of clinical examination in predicting hemodynamic abnormalities was 83 percent. Mortality rates were similar in the clinical and hemodynamic subset calssifications, averaging 2.2 percent in subset I, 10.1 percent in subset II, 22.4 percent in subset III and 55.5 percent in subset IV. Drug interventions in the course of hospitalization resulted in a 38 percent increase in depressed cardiac index and 34 percent decrease in elevated pulmonary capillary pressure. Resolution of clinical abnormalities paralleled this hemodynamic improvement in 70 percent of patients. These data suggest that clinical performance and both clinical and hemodynamic subsets are directly relevant to establishing prognosis and the selection of therapy in patients with acute myocardial infarction.

Acute Disease↗
PubMed1979

Vectorcardiographic detection of early hemodynamic abnormalities in chronic obstructive pulmonary disease.

The ability of the vectorcardiogram to detect mild circulatory abnormalities in patients with chronic obstructive pulmonary disease (COPD) is unclear. Therefore, vectorcardiographic changes were correlated with hemodynamic measurements made at rest and during supine exercise in 32 patients with COPD and no clinical or electrocardiographic evidence of right ventricular hypertrophy. Twelve patients had normal hemodynamic data (group 1), nine had abnormal hemodynamic data only during exercise (group 2), and 11 had abnormal hemodynamic data at rest and during exercise (group 3). The extent of rightward terminal QRS forces noted on the vectorcardiogram was significantly less in group 1 (5.5 +/- 8.7 percent) than in either group 2 (19.0 +/- 10.7 percent) or group 3 (17.8 +/- 14.8 percent). Sixty-five percent (13) of the 20 patients with hemodynamic abnormalities had rightward terminal QRS forces of 15 percent or more, whereas only 8 percent (one) of the 12 patients with normal hemodynamic data had such forces of 15 percent or more. The mean of the rightward terminal QRS forces in 27 age-matched normal subjects was 5.0 +/- 5.4 percent, and only one subject had forces of 15 percent or more. We conclude that hemodynamic abnormalities are frequent in patients with COPD and no clinical evidence of right ventricular hypertrophy and that the vectorcardiogram provides an indirect method of detecting these abnormalities.

Adult↗
PubMedDate not supplied

[Hemodynamic effects of a new antidepolarizing agent: fazadinium bromide].

Studies concerning the hemodynamic effects of this new antidepolarizing agent are scarce and difficult to interpret because of drug interactions, and of an accentuation of vagal tonus related to the use of morphinomimetic analgesics. For a better approach of the effects proper to fazadinium, we have tried to perform a study freed, to a maximum, from any drug interference. We studied the hemodynamic effects to a single dose of 1 mg.kg-1 of fazadinium bromide during 35 minutes in coronary patients normal hemodynamically or rhythmically, non-premedicated, ventilated with 50 p. 100 nitrous oxide in oxygen, and bebore any surgical procedure. All hemodynamic modifications are moderate and maximal 10 minutes after injection. The stroke index decreases 16 p. 100, heart rate increases 6 p. 100 and cardiac index falls 10 p. 100. Total peripheral resistance remains unchanged and mean arterial pressure drops 10 p. 100. Finally pulmonary wedge pressure decreases slightly. None of these modifications are statistically significant. One may, therefore, conclude that fazadinium tolerance, when the drug is freed from any drug interference, in coronary patients normal hemodynamically and free from rhythm disorders is excellent from a hemodynamic and rhythmic point of view. However, other isolated observations of hypovolemic subjects, or patients with atrial fibrillation receiving fazadinium and studied hemodynamically suggest a poorer tolerance in these cases.

Aged↗
PubMed1979

Hemodynamic monitoring in acute myocardial infarction.

The main cause of in-hospital death in patients with acute myocardial infarction is the "power failure syndrome". Hemodynamic monitoring provides precise and current data on the filling and output status of the left ventricle and, when indicated, the right ventricle. The information obtained is used to determine the hemodynamic status more precisely than is possible from conventional clinical assessment. It permits categorization of patients by hemodynamic status; the hemodynamic subset classification of Forrester, Diamond and Swan is a powerful tool in guiding therapy and establishing prognosis in individual patients. In addition to guiding the initiation of therapy, hemodynamic monitoring is useful in the continuing assessment of potent and complex treatment. This therapy is directed at resolving hemodynamic derangements without unfavourably altering the myocardial oxygen supply-demand relationship. Specific clinical indications for hemodynamic monitoring may include confusing or complicated clinical situations in which diagnostic problems exist, complicating mechanical derangements, severe congestive heart failure, cardiogenic shock and clinical research in acute myocardial infarction.

Acute Disease↗