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1.
Hemodynamic data in 43 patients with right and left ventricular infarction and 39 with left ventricular infarction were compared. Right atrial pressure, pulmonary capillary wedge pressure, mean pulmonary artery pressure, left ventricular end-diastolic pressure before and after ventricular angiogram, cardiac index, left ventricular stroke volume index, right ventricular stroke work index were evaluated, as well as ratios of right atrial and pulmonary capillary wedge pressure, right and left ventricular end-diastolic pressure, right ventricular end-diastolic and pulmonary capillary wedge pressure, left ventricular ejection fraction calculated from left ventricular angiogram, Berentey's score, and cardiac volume index. Using ONEWAY analysis there was no significant difference between the two groups in period of rehabilitation. In 15 patients with right ventricular infarction regression of ECG changes was observed in lead V3R also without significant influence on hemodynamic data.  相似文献   

2.
Cardiac catheterization and submaximal exercise testing was performed in 38 patients after repair of tetralogy of Fallot (TF), and compared to 6 control patients who had functional murmurs. Cardiac index, heart rate, and stroke volume index were significantly lower in the TF group than in the control group. Right and left ventricular end-diastolic pressure increased significantly during exercise, which was not found in the control group. Total pulmonary vascular resistance (TPVR), which decreased significantly with exercise in the control group, did not change remarkably during exercise. TPVR was significantly higher in the TF group than in the control group both at rest and during exercise. Several factors were compared between patients with good cardiac index (> 5.0 l/min/m2; Group 1) and poor cardiac index (< 5.0 l/min/m2; Group 2) during exercise. Stroke volume index, right ventricular ejection fraction at rest were significantly higher in Group 1 than Group 2. TPVR, right and left ventricular end-diastolic and end-systolic volume index were significantly lower in Group 1 than in Group 2. There was no significant difference in heart rate, left ventricular ejection fraction, residual pulmonary stenosis, right to left ventricular systolic pressure ratio, and severity of pulmonary regurgitation between two groups. These findings indicate that abnormalities of exercise tolerance in patients after repair of TF were related to poor response of heart rate, pulmonary vascular resistance, and systolic and diastolic ventricular function.  相似文献   

3.
BACKGROUND: Monitoring left ventricular preload is critical to achieve adequate fluid resuscitation in patients with hypotension and sepsis. This prospective study tested the correlation of the pulmonary artery occlusion pressure, the left ventricular end-diastolic area index measured by transesophageal echocardiography, the arterial systolic pressure variation (the difference between maximal and minimal systolic blood pressure values during one mechanical breath), and its delta down (dDown) component (= apneic - minimum systolic blood pressure) with the response of cardiac output to volume expansion during sepsis. METHODS: Preload parameters were measured at baseline and during graded volume expansion (increments of 500 ml) in 15 patients with sepsis-induced hypotension who required mechanical ventilation. Each volume-loading step (VLS) was classified as a responder (increase in stroke volume index > or = 15%) or a nonresponder. Successive VLSs were performed until a nonresponder VLS was obtained. RESULTS: Thirty-five VLSs (21 responders) were performed. Fluid loading caused an overall significant increase in pulmonary artery occlusion pressure and end-diastolic area index, and a significant decrease in systolic pressure variation and delta down (P < 0.01). There was a significant difference between responder and nonresponder VLSs in end-diastolic area index, systolic pressure variation, and dDown, but not in pulmonary artery occlusion pressure. Receiver-operator curve analysis showed that dDown was a more accurate indicator of the response of stroke volume index to volume loading than end-diastolic area index and pulmonary artery occlusion pressure. A dDown component of more than 5 mmHg indicated that the stroke volume index would increase in response to a subsequent fluid challenge (positive and negative predictive values: 95% and 93%, respectively). CONCLUSION: The dDown component of the systolic pressure variation is a sensitive indicator of the response of cardiac output to volume infusion in patient with sepsis-induced hypotension who require mechanical ventilation.  相似文献   

4.
Long-term systemic ventricular function at rest and during supine bicycle exercise was studied in 12 patients with atrioventricular discordance (AVD group) using multigated radionuclide blood pool imaging. For comparison, similar measurements were made in eight children (control group). The mean age at the exercise test was 12.3 years in AVD group and was 14.8 years in the control group. In AVD group, ages at the operation ranged from three to 21 years (mean 12.3 years), and the exercise test was performed from one to 9.8 years after the operation (mean 5.3 years). The operative procedures in AVD group consisted of closure of the ventricular septal defect in 11 patients, extracardiac conduit between the left ventricle and the pulmonary artery in nine patients, postero-lateral left ventricular outflow reconstruction in two patients, tricuspid annuloplasty in one patient, and tricuspid valve replacement in one patient. Exercise tolerance of AVD group was less than that of the control group. Heart rate and blood pressure were significantly increased during exercise in both groups. In the control group, end-diastolic count index (EDCI) (= end-diastolic volume) remained unchanged and end-systolic count index (ESCI) (= end-systolic volume) decreased during exercise. In contrast, both EDCI and ESCI were decreased in AVD group. As a consequence, systemic right ventricular ejection fraction (RVEF) increased during exercise in the control group, but remained unchanged in AVD group. Although stroke count index (SCI) (= stroke volume index) did not increased during exercise in AVD group, output count index (OCI) (= cardiac index) increased with the increase of heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
OBJECTIVE: To examine the usefulness of preload indices obtained by transoesophageal echocardiography (TOE) for estimating stroke volume at various levels of cardiac index. DESIGN: Prospective clinical study. SETTING: Intensive care unit with surgical patients. PATIENTS: 16 ventilated patients monitored via Swan-Ganz catheterization and TOE. INTERVENTIONS: Echocardiographic images of left ventricular cross-sectional short-axis areas were analysed for the preload indices end-diastolic area (EDA), stroke area and end-diastolic wall stress. The relation between these indices and stroke volume, calculated from thermodilution cardiac output, was analysed in all patients and in nine patient groups discriminated by various ranges in heart rate (< or = 70 to > 110 beats/min), pulmonary artery occlusion pressure (< or = 8 to > 12 mmHg) and cardiac index (< or = 3.0 to > 4.2 l/min per m2). MEASUREMENTS AND RESULTS: Overall stroke volume (n = 155) correlated significantly (p < 0.0001) with EDA (r = 0.89) and stroke area (r = 0.80). The correlation with end-diastolic wall stress was non-significant (r = 0.51). Linearity in the relation between stroke volume and EDA or stroke area was independent of variations in heart rate and pulmonary artery occlusion pressure. Stroke volume correlated well with EDA and stroke area, when cardiac index was normal or high, but the relation slightly deteriorated (r = 0.63 to < or = 0.72) when the cardiac index was low. Changes in EDA and stroke area by more than 1, 2 or 3 cm2 were weak predictors for changes in stroke volume greater than 20%. CONCLUSIONS: Stability of the relation between echocardiographic preload indices and stroke volume emphasize the potential of TOE for continuous preload monitoring in the critically ill.  相似文献   

6.
BACKGROUND: Reports of pulmonary edema complicating inhaled nitric oxide therapy in patients with chronic heart failure and pulmonary hypertension have raised the concern that inhaled nitric oxide may have negative inotropic effects. METHODS AND RESULTS: We investigated the effect of multiple doses of inhaled nitric oxide (20, 40 and 80 ppm) on left ventricular contractile state in 10 open-chest pigs. Pressure-volume loops were generated during transient preload reduction to determine the end-systolic pressure-volume relationship and the stroke work-end-diastolic volume relation. Inhaled nitric oxide had no effect on systemic vascular resistance, cardiac output, end-systolic pressure volume relationship or stroke work-end-diastolic volume relation under normal conditions. After induction of pulmonary hypertension (intravenous thromboxane A2 analog), inhalation of nitric oxide (80 ppm) resulted in a reduction in pulmonary vascular resistance (mean +/- standard error of the mean) from 10.4 +/- 3 to 6.5 +/- 2 Wood units (p < 0.001) and in pulmonary artery pressure from 44 +/- 4 to 33 +/- 4 mm Hg (p < 0.05). Left ventricular end-diastolic volume rose from 53 +/- 9 ml to 57 +/- 10 ml (p = 0.02). No statistically significant change in cardiac output or systemic vascular resistance was observed. Inhaled nitric oxide had no effect on end-systolic pressure-volume relationship or stroke work-end-diastolic volume relation. CONCLUSIONS: In a porcine model of pulmonary hypertension, inhaled nitric oxide does not impair left ventricular contractile function. Therefore the cause of pulmonary edema observed in some patients receiving inhaled nitric oxide is not due to a negative inotropic action of this therapy.  相似文献   

7.
Pulmonary arterial end-diastolic and mean right atrial pressures were compared in 25 patients with acute myocardial infarction and in one patient with unstable angina. No consistent relationship was observed between these pressures. Simultaneous ventricular function curves relating the stroke work of each ventricle to its respective filling pressure were constructed on 34 occasions, dextran infusion or diuresis being used to alter the filling pressure. The curves from each ventricle were described mathematically by a quadratic (parabolic) function as well as by a straight line function and then compared by canonical correlation analysis. Alterations in the left ventricular function curves occurred with and without depression or right ventricular function curves. These hemodynamic measurements demonstrate that acute myocardial infarction can alter the relationship between left and right ventricular function.  相似文献   

8.
OBJECTIVE: To examine the effects of external positive end-expiratory pressure (PEEP) on right ventricular function in chronic obstructive pulmonary disease (COPD) patients with intrinsic PEEP (PEEPi). DESIGN: Prospective study. SETTING: General intensive care unit in a university teaching hospital. PATIENTS: Seven mechanically ventilated flow-limited COPD patients (PEEPi = 9.7 +/- 1.3 cmH2O, mean +/- SD) with acute respiratory failure. INTERVENTION: Hemodynamic and respiratory mechanic data were collected at four different levels of PEEP (0-5-10-15 cmH2O). MEASUREMENTS AND RESULTS: Hemodynamic parameters were obtained by a Swan-Ganz catheter with a fast response thermistor. Cardiac index (CI) and end-expiratory lung volume (EELV) reductions started simultaneously when the applied PEEP was approximately 90% of PEEPi measured on 0 cmH2O (ZEEP). Changes in transmural intrathoracic pressure (PEEPi,cw) started only at a PEEP value much higher (120%) than PEEPi. The reduction in CI was related to a decrease in the right end-diastolic ventricular volume index (RVEDVI) (r = 0.61; p < 0.001). No correlation between CI and transmural right atrial pressure was observed. The RVEDVI was inversely correlated with PEEP-induced changes in EELV (r = -55; p < 0.001), but no with PEEPi,cw (r = -0.08; NS). The relationship between RVEDVI and right ventricular stroke work index, considered an index of contractility, was significant in three patients, i.e., PEEP did not change contractility. In the other patients, an increase in contractility seemed to occur. CONCLUSIONS: In COPD patients an external PEEP exceeding 90% of PEEPi causes lung hyperinflation and reduces the CI due to a preload effect. The reduction in RVEDVI seems related to changes in EELV, rather than to changes in transmural pressures, suggesting a lung/heart volume interaction in the cardiac fossa. Thus, in COPD patients, application of an external PEEP level lower than PEEPi may affect right ventricular function.  相似文献   

9.
We performed unilateral pulmonary arterial occlusion test (UPAO) for the preoperative evaluation of lung function in patients undergoing lung resection. In this test, the main pulmonary artery of either side is occluded to simulate postoperative functional status. In order to evaluate the right ventricular hemodynamic function, we measured right ventricular ejection fraction (RVEF) and right ventricular end-diastolic volume index (RVEDVI) throughout UPAO by thermodilution method. We investigated the relationships between changes in right ventricular hemodynamic function and postoperative complications related to cardiac functions, namely arrhythmias or heart failure. Thirty-four patients without heart disease prior to lung resection were examined by UPAO, and RVEF and RVEDVI were measured. Analyses demonstrated that changes in RVEF were inversely correlated with changes in RVEDVI. In 6 cases, RVEDVI increased from control by over 20% during UPAO. All of these patients had postoperative cardiac complications. The hypothetical ventricular function curves showed a large increase in RVEDVI relative to right ventricular stroke work index (RVSWI), suggesting a decrease in right ventricular function. In conclusion, these results suggest that changes in RVEDVI during UPAO may predict postoperative cardiac complications in patients undergoing pulmonary resection.  相似文献   

10.
Serial invasive and noninvasive (systolic time interval) measurements of left ventricular performance were obtained in six healthy volunteers during general anesthesia employing the following sequence: thiopental induction, succinylcholine (prior to endotracheal intubation), and halothane--100 per cent oxygen at 1.25 and 1.75 MAC. Heart rate (HR), mean pulmonary arterial "wedge" pressure (PAW) and mean systemic arterial pressure (MAP) were measured continuously; cardiac index and systolic time intervals (STI's) were measured during each intervention. At both levels of halothane, MAP and stroke work index decreased (both P less than 0.02), while HR and systemic vascular resistance did not change. At 1.25 MAC halothane PAW was unchanged, but at 1.75 MAC PAW increased from 8 +/- 4 (SD) to 11 +/- 5 torr (P less than 0.02). Preload was altered at 1.25 MAC by administration of 600-1,000 ml lactated Ringer's solution; PAW increased from 9 +/- 4 to 17 +/- 3 torr (P less than 0.01). At 1.75 MAC halothane, volume expansion increased PAW in a similar manner, but the resultant ventricular function curve was depressed compared with 1.25 MAC halothane. In additon, at each level of halothane anesthesia, the ventricular function curve was depressed compared with results obtained in awake normal subjects. Afterload was altered at 1.25 MAC halothane by infusion of phenylephrine sufficient to raise MAP by 30 per cent. This intervention resulted in a greater depression of cardiac performance than that observed at 1.75 MAC halothane alone. Although alterations in STI's were directionally similar to changes observed in invasive hemodynamic measurements, STI's were sensitive to acute alternations in loading conditions. It is concluded that the levels of halothane commonly employed for general anesthesia significantly depress left ventricular performance in normal subjects, as evidenced by abnormal responses to alterations in preload and afterload, and that STI's should not be employed for routine measurement of left ventricular performance during anesthesia unless both the afterload and the preload on the myocardium are known.  相似文献   

11.
Left ventricular function was evaluated echocardiographically within 24 hours of cardiac catheterization in 45 children with fixed aortic stenosis. Left ventricular systolic time intervals, mean velocity of circumferential fiber shortening, left ventricular end-diastolic volume and shortening fraction were evaluated. Some patients with severe aortic stenosis had a shortened preejection period, prolonged ejection time and increased mean velocity of circumferential fiber shortening in comparison with normal subjects, but these findings were not consistent within the group with severe aortic stenosis or apparent in patients with mild or moderate aortic stenosis. Left ventricular end-diastolic volume was smaller in children with severe obstruction than in normal children. Evaluation of the shortening fraction provided good separation of patients with significant obstruction from those with mild disease. Further, there was a linear correlation between the shortening fraction and the left ventricular-aortic gradient demonstrated at cardiac catheterization. This correlation was also of use in evaluating the response of patients to surgical relief of obstruction. Pre- and postoperative echocardiographic evaluation of the shortening fraction appears to provide a readily available noninvasive method of assessing the course and severity of obstruction in fixed aortic stenosis in children.  相似文献   

12.
Decisions about enteral tube feeding among the elderly   总被引:1,自引:0,他引:1  
OBJECTIVE: To characterize the acute actions and physiologic dose profile of epinephrine, as a single inotrope, in patients with septic shock. DESIGN: Prospective clinical study. The relationship between epinephrine dose and cardiovascular variables was analyzed using repeated-measures analysis of variance. SETTING: ICU in a university teaching hospital. PATIENTS: Eighteen patients with septic shock, mean age 64 +/- 8 (SD) yrs, and with a mean admission Acute Physiology and Chronic Health Evaluation (APACHE II) score of 23 (range 14 to 35). INTERVENTIONS: Initial volume loading and the measurement of a baseline hemodynamic profile were followed by the administration of an epinephrine infusion at 3 microgram/min with subsequent increments of 3 micrograms/min and the determination of a hemodynamic profile after each dose increment. Therapy was titrated to clinical goals of perfusion and restoration of premorbid systolic arterial BP. MEASUREMENTS AND MAIN RESULTS: After volume loading, mean hemodynamic indices were as follows: mean arterial pressure (MAP) 62 +/- 7 mm Hg; cardiac index 3.8 +/- 1.1 L/min/m2; left ventricular stroke work index 25 +/- 11 g.m/m2; oxygen delivery (Do2) index 460 +/- 168 mL/min/m2; and oxygen consumption (VO2) index 165 +/- 64 mL/min/m2. In the dose range of 3 to 18 microgram/min, epinephrine produced linear increases in average heart rate, MAP, cardiac index, left ventricular stroke work index, stroke volume index, VO2, and DO2. No effect was noted on pulmonary artery occlusion pressure (PAOP), mean pulmonary arterial pressure, or systemic vascular resistance index. CONCLUSIONS: Epinephrine increases DO2 in septic shock by increasing cardiac index without an effect on systemic vascular resistance index or PAOP.  相似文献   

13.
The left ventricular hemodynamics of 70 patients with acute myocardial infarction were determined from measurements of pulmonary arterial end-diastolic pressure, cardiac index, mean arterial pressure and heart rate during the acute phase(first study, 5 hours after admission), 4 to 6 weeks later (second study, during convalescence) and in 35 percent of all subjects 6 to 12 months after the acute infarction (third study). Serial analysis of serum creatine kinase was carried out during the acute phase. The peak CK value normalized for body surface area was used as a rough index of the extent of the acute myocardial necrosis. The condition of all survivors of the acute stage improved. Patients with only slightly reduced left ventricular performance during the acute stage recovered to nearly normal during convalescence. The condition of patients with greatly reduced left ventricular function also improved but remained impaired during convalescence. In all patients the main changes in left ventricular hemodynamics occurred within the first 4 to 6 weeks; there was almost no further alteration during the following 9 months.  相似文献   

14.
BACKGROUND: Inhaled nitric oxide has been shown to be a potent and selective pulmonary vasodilator. Reports of increases in left ventricular end-diastolic pressure and episodes of pulmonary edema during the clinical use of inhaled nitric oxide in patients with preexisting left ventricular dysfunction have raised concerns that this agent may have myocardial depressant effects. We therefore undertook a study of the effects of inhaled nitric oxide on myocardial contractility in a porcine model of ventricular failure and pulmonary hypertension. METHODS: After inducing heart failure in 10 pigs by rapid ventricular pacing, hemodynamic measurements and pressure-volume diagrams (by the conductance method) were obtained in six animals at baseline and during administration of inhaled nitric oxide at concentrations of 20 and 40 ppm. Myocardial contractile state was assessed by the end-systolic pressure-volume relationship and preload-recruitable stroke work, whereas diastolic function was measured in terms of the end-diastolic pressure-volume relationship and the pressure decay time constant T. RESULTS: Baseline hemodynamics reflected heart failure and pulmonary hypertension, and inhaled nitric oxide induced significant reductions in mean pulmonary artery pressure and pulmonary vascular resistance. Although left ventricular end-diastolic pressure increased during administration of inhaled nitric oxide, no changes were observed in measures of systolic or diastolic function. CONCLUSIONS: Inhaled nitric oxide reduced pulmonary vascular resistance but did not alter myocardial contractility or diastolic function. Increases in left ventricular end-diastolic pressure during inhaled nitric oxide therapy are therefore not due to myocardial depression and may be related to increases in volume delivery to the left side of the heart resulting from reduced pulmonary vascular resistance.  相似文献   

15.
Fourteen cardiac transplant candidates were studied with cardiopulmonary exercise testing at baseline and while breathing nitric oxide (40 ppm). Oxygen consumption at the anaerobic threshold was improved by breathing nitric oxide in patients with pulmonary hypertension and in patients with an elevated left ventricular end-diastolic volume index.  相似文献   

16.
Right ventricular function curves as measured by right ventricular stroke work were normal in all control lambs, whereas three of five lambs with banded pulmonary arteries had relatively flat curves. Left ventricular function was similarly normal in the control group as compared to a near zero slope function curve in the banded group. Regional myocardial blood flow to the septum and right and left ventricles was similar in control and banded lambs. At rest right ventricular coronary vascular resistance was lower in the banded than in the control group and decreased in both groups during both isoproterenol and dextran stress states. In general, both groups had a similar ratio of right to left ventricular oxygen supply to demand ratio. These results show first that there is minimal, if any, biventricular functional reserve in lambs with persistent right ventricular hypertension, and second, that there is substantial coronary vascular reserve in both normal and banded groups.  相似文献   

17.
18.
The pressure and volume demands of the right and left ventricles may dramatically change following selective pulmonary vasodilation in newborns with pulmonary hypertension. Thus, ventricular planimetry was performed by two-dimensional echocardiography in 35 newborns with lung disease and increased pulmonary vascular resistance who were treated with inhaled nitric oxide to determine the influence of therapy on right and left ventricular size and function. The end-diastolic and end-systolic areas of each ventricle were measured from apical 4-chamber images before, and 30 to 60 minutes after, the onset of 20 parts per million inhaled nitric oxide. Estimates of ventricular function were determined by the systolic decrease in ventricular area, (diastolic area - systolic area) x 100/diastolic area. Heart rate, systemic blood pressure, and left ventricular areas did not change. However, the oxygenation index, the proportion of right-to-left ductal shunt (nonrestrictive ductus arteriosus, n = 22), the systolic pulmonary arterial pressure (closed or restrictive ductus arteriosus, n = 13), and the right ventricular diastolic and systolic areas were decreased after nitric oxide inhalation. The baseline systolic decrease in left ventricular area was lower in a subgroup of patients who developed an increase in left ventricular diastolic area following nitric oxide inhalation. Thus, nitric oxide improves pulmonary hemodynamics and decreases right ventricular size in newborns with lung disease and pulmonary hypertension. However, newborns may develop an increase in left ventricular size if left ventricular function is decreased prior to therapy.  相似文献   

19.
In chronic obstructive pulmonary disease (COPD), the development of pulmonary hypertension is common. This study was performed to assess the signs of right ventricular (RV) pressure overload and RV failure in COPD. In 8 COPD patients without primary cardiac disease, RV wall thickness, mass, and end-diastolic volume were measured by cardiac-triggered cine MRI. MR phase-contrast velocity quantification was used to measure stroke volume and the patterns of flow into and out of the RV. Data of patients were tested versus those of a control group matched for age (n = 8). Results showed that the RV wall thickness was increased (.6 +/- 0.1 vs 0.4 +/- 0.1 cm, P < .001). RV mass was increased (67 +/- 11 vs 57 +/- 5 g, P < .005). RV stroke volume was decreased (57 +/- 13 vs 71 +/- 13 ml, P < .01), but RV ejection fraction was not different. In the main pulmonary artery flow, the quotient of acceleration time divided by ejection time was decreased (33 +/- 5% vs 38 +/- 4%, P < .05), which is indicative of pulmonary hypertension. In conclusion, this MRI protocol provides a tool to assess the effects of RV pressure overload in COPD before heart failure has become manifest.  相似文献   

20.
Our purpose was to evaluate the hemodynamic effects of olprinone hydrochloride early after coronary artery bypass grafting (CABG). Fifteen patients undergoing CABG were administered a constant infusion of 0.1 microgram/kg/min of olprinone and continued for 4 hours. No bolus infusion of olprinone was administered before continuous infusion. Systolic systemic arterial pressure, systolic pulmonary arterial pressure, systemic vascular resistance and pulmonary vascular resistance were significantly decreased. There were no significant changes in heart rate, mean central venous pressure, mean left atrial pressure and left ventricular stroke work index. Cardiac index was significantly increased, but a correlation between cardiac index and mixed venous blood oxygen saturation was not found. Double product was significantly decreased, which described above suggest that olprinone achieved improvement of left cardiac function without more myocardial oxygen consumption. Severe transient hypotension (systolic arterial pressure < 80 mmHg) after infusion of olprinone was observed in three patients. Olprinone administered soon after CABG surgery had beneficial effects in terms of improvement of hemodynamic status without more oxygen consumption and reduction of pulmonary vascular resistance. However transient hypotension was a serious clinical problem in patients after open heart surgery, especially in CABG patients who need suitable systolic arterial pressure to keep enough blood perfusion of arterial bypass grafts.  相似文献   

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