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1.
Pulmonary artery hypertension in patients with left ventricular dysfunction is related to poor outcome but the role of cardiac functional abnormalities in the genesis of pulmonary hypertension remains unknown. The aim of this prospective study was to identify the determinants of pulmonary hypertension in 102 consecutive patients with primary left ventricular dysfunction (ejection fraction < 50%). Systolic pulmonary artery pressure was measured by continuous wave Doppler. Left ventricular systolic and diastolic function, severity of functional mitral regurgitation, cardiac output, and left atrial volume were assessed using Doppler echocardiography. In patients with left ventricular dysfunction, systolic pulmonary artery pressure was increased (51 +/- 14 mmHg, range 23 to 87 mmHg). Mitral deceleration time (r = -0.61; p = 0.0001) and mitral effective regurgitant orifice (r = 0.50; p = 0.0001) were the strongest parameters related to systolic pulmonary artery pressure. Multivariate analysis identified these two variables as the strongest predictors of systolic pulmonary artery pressure in association with the mitral E/A ratio (p = 0.006) and age (p = 0.005). In conclusion, pulmonary hypertension is common and variable in patients with left ventricular dysfunction. It is closely related to diastolic dysfunction and severity of functional mitral regurgitation but not independently to the degree of left ventricular systolic dysfunction. These findings underline the importance of assessing diastolic function and quantifying mitral regurgitation in patients with left ventricular dysfunction.  相似文献   

2.
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   

3.
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   

4.
OBJECTIVE: To determine whether pulmonary hypertension developed in a coronary artery-ligated rabbit model of left ventricular dysfunction (LVD) and to examine the effects of i.v. 5-hydroxytryptamine (5-HT) and endothelin-1 (ET-1) on pulmonary arterial pressure (PAP). METHODS: Eight weeks after experimental coronary artery ligation or sham operation, ejection fractions were assessed by echocardiography. The rabbits were later anaesthetised and pulmonary arterial pressure was measured via a catheter inserted into the pulmonary artery via the right external jugular vein. 5-HT (1-400 micrograms/kg) and ET-1 (0.001-4 nmol/kg) were administered i.v. RESULTS: Ejection fraction was significantly decreased from 76.6 +/- 1.4% in sham-operated to 42.2 +/- 1.3% in coronary artery-ligated rabbits (n = 9 in each group; P < 0.001), consistent with LVD. Baseline mean pulmonary arterial pressure was significantly increased in the coronary artery-ligated group compared to the shams, (16.5 +/- 0.5 vs. 11.5 +/- 0.8 mmHg; P < 0.001). A significant degree of right ventricular hypertrophy was found in the coronary artery-ligated rabbits (0.70 +/- 0.04 g/kg final body weight (f.b.wt.), n = 8 cf. 0.48 +/- 0.02 g/kg f.b.wt. in sham-operated controls, n = 8; P < 0.001). There was a significant increase in the percentage of muscularised pulmonary vessels adjacent to alveolar ducts and alveoli < 60 microns i.d. in the LVD rabbits compared with their sham-operated controls (8.5 +/- 0.4 cf. 20 +/- 0.5%; P < 0.0005). 5-HT produced a greater response in the coronary artery-ligated rabbits (a maximum increase of 8.7 +/- 1.0 mmHg in mean pulmonary artery pressure vs. 4.6 +/- 1.5 mmHg for sham-operated controls; P < 0.05). ET-1 did not have any effect on pulmonary arterial pressure in either group. CONCLUSION: In the rabbit, LVD secondary to coronary artery ligation, causes right ventricular hypertrophy, pulmonary vascular remodelling, and an increased PAP consistent with the onset of pulmonary hypertension (PHT). The greater PAP response to i.v. 5-HT in the PHT group supports the hypothesis that this substance could be involved in the development of PHT. A role for ET-1 cannot be excluded, despite its lack of effect on PAP when intravenously administered in either group.  相似文献   

5.
Right ventricular systolic sub-periods were examined in the group of 18 healthy subjects, basing on simultaneous electrocardiographic, phonocardiographic and pulmonary artery pressure tracings. The values established were compared with corresponding left ventricular systolic periods and correlated with selected hemodynamic parameters. Following mean values of the right ventricular systolic sub-periods were found: Q -- 1. sound interval = 0.051 sec., systolic time = 0.404 sec., ejection period = 0.319 sec., pre-ejection period = 0.085 sec., and isovolumetric contraction time = 0.034 sec. Both the right ventricular systolic and ejection periods were significantly longer than the corresponding left ventricular systolic ones. The ratio: right ventricular pre-ejection period to ejection period was lower than that calculated for the left ventricle. Both the right ventricular systolic and ejection periods negatively correlated with heart rate, whereas the ratio: right ventricular isovolumetric contraction time to ejection period depended on pulmonary artery pressure, pulmonary resistance and right ventricular work index.  相似文献   

6.
OBJECTIVES: The purpose of this study was to determine whether left atrial size and ejection fraction are related to left ventricular filling pressures in patients with coronary artery disease. BACKGROUND: In patients with coronary artery disease, left ventricular filling pressures can be estimated by using Doppler mitral and pulmonary venous flow velocity variables. However, because these flow velocities are age dependent, additional variables that indicate elevated left ventricular filling pressures are needed to increase diagnostic accuracy. METHODS: Echocardiographic left atrial and Doppler mitral and pulmonary venous flow velocity variables were correlated with left ventricular filling pressures in 70 patients undergoing cardiac catheterization. RESULTS: Left atrial size and volumes were larger and left atrial ejection fractions were lower in patients with elevated left ventricular filling pressures. Mean pulmonary wedge pressure was related to mitral E/A wave velocity ratio (r = 0.72), left atrial minimal volume (r = 0.70), left atrial ejection fraction (r = -0.66) and atrial filling fraction (r = -0.66). Left ventricular end-diastolic and A wave pressures were related to the difference in pulmonary venous and mitral A wave duration (both r = 0.77). By stepwise multilinear regression analysis, the ratio of mitral E to A wave velocity was the most important determinant of pulmonary wedge (r = 0.63) and left ventricular pre-A wave (r = 0.75) pressures, whereas the difference in pulmonary venous and mitral A wave duration was the most important variable for both left ventricular A wave (r = 0.75) and left ventricular end-diastolic (r = 0.80) pressures. The sensitivity of a left atrial minimal volume > 40 cm3 for identifying a mean pulmonary wedge pressure > 12 mm Hg was 82%, with a specificity of 98%. CONCLUSIONS: Left atrial size, left atrial ejection fraction and the difference between mitral and pulmonary venous flow duration at atrial contraction are independent determinants of left ventricular filling pressures in patients with coronary artery disease. The additive value of left atrial size and Doppler variables in estimating filling pressures and the possibility that left atrial size may be less age dependent than other mitral and pulmonary venous flow velocity variables merit further investigation.  相似文献   

7.
BACKGROUND: Treadmill testing is usually preferred over cycle ergometry because of the greater sensitivity in diagnosing coronary artery disease. Treadmill testing has only recently been used with radionuclide angiography (RNA) because patient motion makes RNA imaging difficult. In this study we evaluate the comparability of treadmill and cycle exercise RNA with a dual isotope motion correction technique. METHODS AND RESULTS: Volunteer patients (n = 27) performed first-pass RNA during maximal exercise using both cycle ergometer and treadmill. Exercise capacity was greater during treadmill exercise (8.1 +/- 2.4 vs 7.5 +/- 2.2 METs). Twenty-three of 27 treadmill and all cycle ergometer exercise studies were technically adequate. Maximal heart rate was greater during treadmill exercise (150 +/- 24 vs 143 +/- 25 beats * min-l), however, systolic blood pressure was greater during cycle ergometry (174 +/- 23 vs 188 +/- 25 mmHg), resulting in no difference in heart rate times systolic blood pressure (25.7 +/- 7.2 vs 26.9 +/- 6.0). There were no differences between treadmill and cycle ergometer for peak exercise left ventricular ejection fraction (56% +/- 13% vs 57% +/- 14%) (r = 0.89). Calculated left ventricular end-diastolic volume was not different at rest (183 +/- 42 ml vs 176 +/- 44 ml) but differed significantly at peak exercise (282 +/- 75 ml vs 231 +/- 60 ml). The clinical impression, based on wall motion and left ventricular ejection fraction was very similar between treadmill and cycle ergometer. CONCLUSION: Treadmill exercise RNA is feasible, with about 85% of studies likely to be technically adequate. The overall clinical results are very similar to cycle exercise RNA, although the ordinarily expected advantages of treadmill exercise were largely absent.  相似文献   

8.
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   

9.
To elucidate how symptoms and signs of chronic heart failure are related to the filling pressure and cardiac output at rest, 58 patients (55 males, 3 females, mean age 57 +/- 9 years, range 30-75) with left ventricular ejection fraction (LVEF) < or = 30% and a lesion > or = 50% on a major coronary branch have been selected from patients submitted in 1985-1993 to a complete right and left cardiac catheterization including ventriculography and coronary angiography. Patients with recent myocardial infarction (MI), unstable angina, associated heart diseases or recent changes in body weight and in diuretic therapy were excluded. Clinical data were obtained at cardiac catheterization time from history, physical examination, chest X-ray and ECG. Patients with angina as limiting symptom were excluded from NYHA functional classification. Pulmonary venous congestion (PVC) was defined on X-ray as: absent, venous redistribution, interstitial pulmonary edema (IPE). Mean pulmonary capillary wedge pressure (PCWP) was recorded under fluoroscopy and cardiac index was measured by the Fick method. On the whole group, 96% of patients had had one or more MI (on ECG necrosis was anterior in 58%, inferior in 9%, anterior and inferior in 26%), 69% were in NYHA functional class III or IV, 54% had IPE and 45% had mitral regurgitation. 71% were under treatment with digitalis, 74% with diuretics and 39% with ACE-inhibitors. PCWP was correlated with LVEDV (r = 0.34; p < 0.001) but neither with LV mass nor with LV mass/volume ratio. It was significantly higher (p < 0.01) in patients with mild-moderate mitral regurgitation, in patients with necrosis involving both anterior and inferior walls (26 +/- 6 vs 21 +/- 8 mmHg in patients with single wall necrosis, p < 0.05) and in patients with multiple MI (26 +/- 7 vs 20 +/- 8 mmHg in patients with no or single MI, p < 0.02). Moreover, it was neither correlated with functional classification nor with PVC: of patients with PCWP > 24 mmHg, 14% were in II NYHA functional class and 21% had no PVC while of patients with PCWP < 15 mmHg, 36% were in NYHA functional class IV and 7% had IPE. Cardiac index was reduced below 2.3 l/min/m2 in 21% of patients: these patients had increased pulmonary (p < 0.0002) and systemic (p < 0.0001) vascular resistance, increased systolic (p < 0.001) and diastolic (p < 0.01) pulmonary artery pressure and reduced LVEF (p < 0.01) and right ventricular ejection fraction (p < 0.03). Furthermore, on the whole patients an inverse correlation was found between cardiac index and functional classification (r = -0.42; p < 0.01). The reliability of NYHA functional class IV, physical signs of heart failure and IPE for estimating PCWP > 24 mmHg and cardiac index < 2.3 l/min/m2 was rather limited although high specificity was shown for gallop sounds (92 and 97%) and jugular vein distension (88 and 97%). In conclusion, in coronary patients with chronic severe LV systolic dysfunction a mismatch between clinical data and central hemodynamics is not rare. The reliability of functional class, X-ray PVC and physical signs to predict central hemodynamics in fairly limited.  相似文献   

10.
BACKGROUND: The prognosis of chronic heart failure has been studied extensively, but factors predicting short-term outcome in patients with severe chronic heart failure are still poorly defined, and the current indications for heart transplantation as a treatment for end-stage heart failure need on objective analysis. METHODS: Purpose of the study was to identify the determinants of short-term prognosis in a group of 142 consecutive ambulatory patients (mean age 49.8 +/- 11 years). Referred for heart transplantation because of severe chronic heart failure, the patients were admitted with left ventricular ejection fraction markedly depressed and had had symptoms in spite of an optimal standardized medical therapy for at least 1 month. Baseline clinical and instrumental evaluation included right-sided heart catheterization with a flow-directed multilumen thermodilution catheter, which enables determination of pressures, cardiac output, right ventricular volumes, and ejection fraction. RESULTS: Most patients were in New York Heart Association class III (61%) and IV (24%), and the hemodynamic profile was characterized by mean left ventricular ejection fraction of 20.2% +/- 6%, cardiac index of 2.13 +/- 0.6 l/min/m2, pulmonary capillary wedge pressure of 23.1 +/- 11 mm Hg, right atrial pressure of 7.9 +/- 6 mm Hg, right ventricular ejection fraction of 23.2% +/- 12.4%. During a mean follow-up of 11.1 +/- 9.4 months, 33 patients underwent transplantation (23.4%), 41 died (28.8%), and 68 were still alive (47.8%). There was a substantial overlap in left ventricular ejection fraction between patients divided on the basis of outcome, whereas right ventricular ejection fraction was significantly lower in patients who died or underwent transplantation. Cox multivariate analysis showed three independent prognostic variables: cause (p = 0.03), heart failure score (p = 0.001), and right ventricular ejection fraction (p = 0.000). Short-term survival (10 months) was significantly (p = 0.000) different in patients with > or = 24% or < 24% right ventricular ejection fraction. Statistical analysis identified right ventricular ejection fraction as the single variable to be highly correlated with an increased risk of early death. CONCLUSIONS: This study suggests that right ventricular function is a crucial determinant of short-term prognosis in severe chronic heart failure. Statistical analysis identified right ventricular ejection fraction, determined by thermodilution during right-sided heart catheterization, as the single most important predictor of short-term prognosis in a large cohort of patients who had symptoms in spite of a standardized, optimized, multipharmacologic treatment. The variable allows a useful risk stratification in patients with severe chronic heart failure and uniformly depressed left ventricular ejection fraction and provides guidance in the assessment of indications and timing for transplantation.  相似文献   

11.
To assess the hemodynamic effects of afterload reduction in severe aortic regurgitation, nitroprusside was infused at cardiac catheterization in 12 patients with aortic regurgitation. Cardiac hemodynamics, angiographic variables and regurgitant volumes were quantified during control periods, and nitroprusside was infused to reduce systemic systolic pressure to 110 to 125 mm Hg. The following were reduced by the drug: systolic arterial pressure (from 154 +/- 6.4 to 115 +/- 2.3 mm Hg, P less than 0.001); left ventricular end-diastolic pressure (from 23 +/- 2.2 to 11 +/- 1.0 mm Hg, P less than 0.001); systemic vascular resistance (from 1,782 +/- 133 to 1,148 +/- 94 dynes sec cm-5, P less than 0.001); left ventricular end-diastolic volume (from 242 +/- 25 to 196 +/- 19 ml, P less than 0.001); aortic regurgitant fraction (from 0.53 +/- 0.05 to 0.44 +/- 0.06, P less than 0.01); and aortic regurgitant minute volume (from 5.5 +/- 0.10 to 4.3 +/- 0.09 liters/min, P less than 0.01). Effective cardiac index increased (from 2.49 +/- 0.19 to 3.10 +/- 0.24 liters/min per m2, P less than 0.01), and left ventricular ejection fraction rose (from 0.55 +/- 0.03 to 0.61 +/- 0.03, P less than 0.005). These data indicate that afterload reduction with nitroprusside in severe aortic regurgitation improves cardiac performance, greatly decreases left ventricular preload and reduces aortic regurgitant volume. Thus, nitroprusside therapy has special value in severe aortic regurgitation that is of particular benefit in critical clinical conditions.  相似文献   

12.
The effect of late percutaneous transluminal coronary angioplasty (PTCA) of an occluded infarct-related artery on left ventricular ejection fraction was studied in patients with a recent, first Q-wave myocardial infarction in a prospective, randomized study. Forty-four patients (31 men and 13 women, mean age 58 +/- 12 years) with an occluded infarct-related coronary artery were randomized to PTCA (n = 25) or no PTCA (n = 19). Patients received acetylsalicylic acid, a beta blocker and an angiotensin-converting enzyme inhibitor unless contraindicated. Left ventricular ejection fraction was determined at baseline and 4 months. Coronary angiography was repeated at 4 months. Baseline ejection fraction measured 20 +/- 12 days after myocardial infarction was 45 +/- 12% in both groups. PTCA was performed 21 +/- 13 days after the event. The primary PTCA success rate was 72%. One patient in each group died before angiographic follow-up, which was completed in 37 of the remaining 42 patients (88%; 21 with and 16 without PTCA). At 4 months, the infarct-related artery was patent in 43% of PTCA patients and in 19% of no PTCA patients (p = NS). Reocclusion occurred in 40% of patients after successful PTCA. Secondary analyses showed that the change in left ventricular ejection fraction was significantly greater in patients with a patent infarct-related artery (+9.4 +/- 6.2%) than in those with an occluded artery (+1.6 +/- 8.8%; p = 0.0096). Baseline ejection fraction also independently predicted improvement in left ventricular ejection fraction (p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
14.
The operative mortality and morbidity in patients with severe left ventricular dysfunction who undergo coronary artery bypass grafting (CABG) remain high. The low ejection fraction is the major risk factor for operative mortality. However, ejection fraction (EF) alone may not necessarily be an accurate predictor of operative mortality. We studied the correlation between indices of left ventricular volume and operative mortality. One thousand patients undergoing isolated coronary bypass operations were divided into three groups according to their preoperative ejection fraction. Fifty patients (group I) had severe left ventricular dysfunction (EF < or = 0.3), 56 patients (group II) had moderately left ventricular dysfunction (0.3 < EF < or = 0.4) and 894 patients (group III) had good left ventricular function (EF > 0.4). We analyzed the relationship between hospital mortality and left ventricular volume in 106 patients with an EF < or = 0.4. RESULTS: Cardiac index was not significantly different among the three groups. The left ventricular end-diastolic pressure (LVEDP) and mean pulmonary artery pressure in groups I an II were higher than those in group III. The left ventricular end-diastolic volume (LVEDV) was 146 +/- 44 ml/m2 in Group I, 112 +/- 31 ml/m2 in Group II and 82 + 30 ml/m2 in Group III, respectively (Group I versus II, p < 0.05, Group I and II versus III, p < 0.01). The left ventricular end-systolic volume (LVESV) was 111 +/- 38 ml/m2 in Group I, 72 +/- 21 ml/m2 in Group II and 30 +/- 14 ml/m2 in Group III, respectively (Group I versus II, p < 0.05, Group I and II versus III, p < 0.01). The LVEDV and LVESV were higher in Group I than in Group II and both in Groups I and II were higher than in Group III. The hospital mortality of any cause before discharge was 8.0% (4/50) in Group I, 3.6% (2/56) in Group II, and 2.0% (18/894) in Group III. The mortality in Group I was higher than that in Group III, but the mortality between Groups I and II was not different. We assessed correlations between large left ventricle with left ventricular dysfunction and operative mortality in 106 patients with ejection fractions of < or = 0.4. The hospital mortality in patients with both under fraction 0.4 and an LVESV > or = 140 ml/m2 was 50% (4/8). This rate was higher than in patients with an LVESV between 80 and 140 ml/m2 (1.8%, 1/55) (p = 0.0006) and an LVESV less than 80 ml/m2 (2.3%, 1/43), (p = 0.0013). The hospital mortality in patients with an LVEDV > or = 200 ml/m2 was 67% (4/6). It was also higher than that in patients with an LVEDV between 200 and 120 ml/m2 (1.7%, 1/58), (p = 0.0001), and an LVEDV less than 120 ml/m2 (2.4%, 1/42), (p = 0.0004). We conclude that patients with a low ejection fraction and an elevated LVESV or LVEDV are at increased risk for hospital death following CABG.  相似文献   

15.
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   

16.
BACKGROUND: Recently, endoaneurysomorrhaphy has been proposed as a more physiologic repair of postinfarction left ventricular aneurysm than is linear repair. There are only a few studies comparing the short-term and long-term results of the two techniques. METHODS: Clinical outcomes and echocardiographic measurements of left ventricular volume and sphericity in 27 patients who underwent endoaneurysmorrhaphy were compared with those in 20 patients who had linear repair. RESULTS: The two groups were matched with respect to age, gender, comorbid risk factors, functional class, urgency of the operation, and concomitant procedures. Preoperatively, left ventricular ejection fraction was lower in the endoaneurysmorrhaphy group (0.25 +/- 0.08 versus 0.30 +/- 0.09; p = 0.03). Follow-up was available in 44 patients (94%) and ranged from 2 to 86 months (mean, 41.0 +/- 26.5 months). Thirty-day operative mortality, perioperative complications, 5-year survival, and freedom from cardiac death were similar. Early postoperative percentage increase in left ventricular ejection fraction was greater after endoaneurysmorrhaphy (0.51 +/- 0.64 versus 0.18 +/- 0.48; p = 0.036). Long-term functional improvement was significantly better in the endoaneurysmorrhaphy group: At the time of last follow-up, 88% of patients were in New York Heart Association class I/II, compared with 53% after linear repair (p = 0.01). There were no measurable differences between the groups with respect to left ventricular ejection fraction (0.28 +/- 0.11 versus 0.27 +/- 0.11; p = 0.90), left ventricular volume (171.6 +/- 59.1 versus 169.9 +/- 54.4 mL; p = 0.94), and sphericity index (0.61 +/- 0.09 versus 0.61 +/- 0.12; p = 1.0). CONCLUSIONS: Despite having a similar effect on left ventricular geometry, endoaneurysmorrhaphy resulted in a greater increase in postoperative left ventricular ejection fraction and a substantially improved long-term clinical outcome.  相似文献   

17.
The aim of this study was to determine whether low-dose inhalation of nitric oxide (NO) improves pulmonary haemodynamics and gas exchange in patients with stable idiopathic pulmonary fibrosis (IPF). The investigation included 10 IPF patients breathing spontaneously. Haemodynamic and blood gas parameters were measured under the following conditions: 1) breathing room air; 2) during inhalation of 2 parts per million (ppm) NO with room air; 3) whilst breathing O2 alone (1 L.min-1); and 4) during combined inhalation of 2 ppm NO and O2 (1 L.min-1). During inhalation of 2 ppm NO with room air the mean pulmonary arterial pressure (Ppa 25 +/- 3 vs 30 +/- 4 mmHg) and the pulmonary vascular resistance (PVR 529 +/- 80 vs 699 +/- 110 dyn.s.cm-5) were significantly (p < 0.01) lower than levels measured whilst breathing room air alone. However the arterial oxygen tension (Pa,O2) did not improve. The combined inhalation of NO and O2 produced not only a significant (p < 0.01) decrease of Ppa (23 +/- 2 vs 28 +/- 3 mmHg) but also, a remarkable improvement (p < 0.05) in Pa,O2 (14.2 +/- 1.2 vs 11.7 +/- 1.0 kPa) (107 +/- 9 vs 88 +/- 7 mmHg)) as compared with the values observed during the inhalation of O2 alone. These findings suggest that the combined use of nitric oxide and oxygen might constitute an alternative therapeutic approach for treating idiopathic pulmonary fibrosis patients with pulmonary hypertension. However, further studies must first be carried out to demonstrate the beneficial effect of oxygen therapy on pulmonary haemodynamics and prognosis in patients with idiopathic pulmonary fibrosis and to rule out the potential toxicity of inhaled nitric oxide, particularly when used in combination with oxygen.  相似文献   

18.
BACKGROUND: The study was designed to evaluate short and long-term benefits of coronary artery bypass graft in patients with coronary artery disease and severely depressed left ventricular ejection fraction and to identify contemporary risk factors associated with significantly greater mortality in this high-risk subgroup. METHODS: From 1985 to 1995, 200 consecutive pts with EF < or = 0.30 underwent CABG. Among these patients, 60% were older than 70 years. NYHA functional class III/IV was present in 31% of pts. Preoperative mean cardiac index was 2.7 +/- 7 l/min/m2, mean pulmonary artery pressure was 29.9 +/- 7 mm Hg and contractility score (generated by appropriate software for left ventricular kinesis analysis) mean value was 50.1 +/- 11.6 points. Urgent operation was required in 32 pts (16%). The majority of pts were completely revascularized. RESULTS: Operative mortality was 9% (18 pts). Low output syndrome was the most common postoperative complication (13.5%) followed by ventricular arrhythmia (8%), mean length of postoperative hospitalization for survivors was 13 +/- 10 days. Of 23 possible operative risk factors evaluated, four were associated with significantly greater mortality: cardiac index < or = 2.1 l/min/m2, urgent operation, contractility score > or = 80 and associated surgical procedures. Survivors experienced significant improvement in CHF class (p < 0.001) and follow up EF (p < 0.001). Kaplan-Meier estimate of survival at 1 year, 5 years and 8 years was 85%, 65% and 54%. CONCLUSION: Through more careful assessment of preoperative risk factors, patients selection and perioperative management, actually coronary artery bypass graft may be offered to pts with low ejection fraction with reduced morbidity and mortality.  相似文献   

19.
BACKGROUND: The prognosis of acute inferior myocardial infarction is worse when it is complicated by right ventricular infarction. ST elevation in the right precordial leads is one of the reliable methods for detecting acute right ventricular infarction. The purpose of the study was to examine the relation between ST elevation in the right precordial electrocardiographic leads during acute inferior infarction and the severity of right ventricular systolic dysfunction. METHODS: This study analyzed the relation between ST elevation > or = 0.1 mV in V4R and the severity of right ventricular systolic dysfunction in 43 consecutive patients (men/women: 35/8; average age 62+/-9 years) with acute inferior myocardial infarction with a rapid-response Swan-Ganz catheter to measure the right ventricular ejection fraction (RVEF). RESULTS: RVEF was significantly lower in patients with ST elevation (n = 18) than in those without (n = 25) (33%+/-6% vs 40%+/-9%, p = 0.010). If the infarct-related lesion was located in the proximal right coronary artery, RVEF tended to be lower than if the lesion was located in the distal right coronary artery or the left circumflex coronary artery (33%+/-10% vs 37%+/-9% vs 42%+/-9%, p = 0.101). Logistic regression analysis demonstrated that ST elevation in V4R was the only independent predictor of depressed RVEF (odds ratio = 5.31, 95% confidence interval = 1.28 to 22.1, p = 0.022). CONCLUSION: ST elevation in lead V4R during acute inferior myocardial infarction predicts right ventricular systolic dysfunction.  相似文献   

20.
BACKGROUND: Conventional approaches to management of congestive heart failure (CHF) rely on drugs that increase myocardial contractility or reduce ventricular afterload. These approaches often improve cardiac symptoms and survival, but may be associated with significant deleterious effects. An alternative approach is to enhance myocardial energy production. Dichloroacetate (DCA) stimulates pyruvate dehydrogenase activity and accelerates aerobic glucose, pyruvate, and lactate metabolism in myocardial cells. These alterations would be expected to improve myocardial function. HYPOTHESIS: The purpose of the investigation was to assess the efficacy of DCA in patients with left ventricular systolic dysfunction and to examine the mechanism by which improvement occurs. METHODS: A total of 25 patients (16 men, 9 women; age range 31-72 years, mean 59) with CHF and ejection fraction < or = 40% received an intravenous infusion of 50 mg/kg DCA over 15 min. Indices of systolic and diastolic function were obtained by two-dimensional and Doppler echocardiography performed at baseline, 30 min, and 60 min following completion of DCA infusion. RESULTS: Baseline ventricular ejection fraction was 27.3 +/- 9.1%; 17 patients (68%) had nonischemic cardiomyopathy. Heart rate increased after DCA infusion from 73.9 +/- 14.5 to 79.2 +/- 14.9 beats/min at 60 min; p = 0.02. Left ventricular diastolic and systolic volumes increased at 30 min compared with baseline (248.7 +/- 98.1 vs. 259.6 +/- 99.6; p = 0.04, and 180.1 +/- 80.4 vs. 192.2 +/- 84.9; p = 0.002, respectively), but stroke volume (49.2 +/- 19.1 vs. 48.9 +/- 18.1; p = 0.9) and ejection fraction (27.3 +/- 9.1 vs. 25.7 +/- 9.8; p = 0.2) were unchanged. Indices of diastolic function were also unchanged. CONCLUSION: Dichloroacetate infusion in patients with CHF is not associated with improvement in noninvasively assessed left ventricular function.  相似文献   

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