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Investigations of the hemodynamics of pulmonary circulation, right and left heart venticle and ventilatory function of the lungs were carried out in a group of 12 patients with primary pulmonary hypertension. The results were discussed in the light of data obtained in a group of 16 patients with chronic cor pulmonale syndrome and 16 healthy subjects. It was found that patients with primary pulmonary hypertension show a markedly raised pressure in the pulmonary artery mean pressure x = 60.3 +/- 24.2 mm Hg, in the right ventricle (systolic pressure x = 90.6 +/- 27.9 mm Hg, end-diastolic pressure x = 11.7 +/- 4.3 mm Hg), very high total pulmonary vascular resistance (x = 1571 +/- dynes. sec. cm-5) and increased work of right ventricle (x = 2.3 +/- 1.5 kgm/min/m2). In patients with chronic cor pulmonale syndrome the load on the right ventricle was much lower. The indices determining left ventricle function as a pump indicated that this function was impaired, with lower cardiac index (x = 2.1 +/- 0.8 1/min/m2), stroke volume (x = 41.7 +/- 17.2 ml) and left ventricular work (x = 2.7 +/- 1.1 kgm/min/m2). These changes might, however, be due also to impaired blood flow into the left ventricle. In contrast to patients with chronic cor pulmonale syndrome, the indices of ventilatory function of the lungs were normal or only slightly decreased. No significant correlations were observed between hemodynamic indices of pulmonary circulation and right ventricle and the parameters of the ventilatory function of the lungs.
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PMID:Primary pulmonary hypertension--a study of disturbances in circulatory hemodynamics and ventilatory function of the lungs. 122 28

A physical and X-ray examination and echo-, electro- and phonocardiographies were performed in 29 patients with primary pulmonary hypertension. Their central hemodynamics was also conducted by introducing a Swan-Ganz flowing balloon catheter into the right cardiac cavities. With evolving chronic circulatory insufficiency, the patients showed profound hemodynamic changes both in the right (end-diastolic pressure in the right ventricle and atrium rose and ventricular stroke index dropped) and left (heart rate increased, cardiac and stroke indices decreased in the ventricle) ventricles. There were slight changes in peripheral hemodynamics. Pulmonary pressure became lower, but this fact cannot be considered to be positive as this led to significantly lower right ventricular stroke index that indicates the critical diminution in right ventricular performance, unlike cases successfully treated with peripheral vasodilators.
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PMID:[The course of chronic circulatory insufficiency in patients with primary pulmonary hypertension]. 140 62

To test the utility of electrocardiographically gated spin echo nuclear magnetic resonance (NMR) imaging in quantitating right and left ventricular volumes and function in patients with primary pulmonary hypertension, right and left ventricular end-diastolic and end-systolic volumes, stroke volumes and ejection fractions were determined in 11 patients with primary pulmonary hypertension and in 10 subjects with normal echocardiographic findings. Ventricular chamber volumes were computed by summing the ventricular chamber volumes of each NMR slice at end-diastole and end-systole. This technique was verified by comparison of results obtained by this method and with the water displacement volumes of eight water-filled latex balloons and ventricular casts of eight excised bovine hearts. In the patients with primary pulmonary hypertension, right ventricular volume indexes were 121 +/- 45 ml/m2 at end-diastole and 70.1 +/- 41.6 ml/m2 at end-systole; both values were significantly greater than values in the normal subjects (67.9 +/- 13.4 and 27.9 +/- 7.5 ml/m2, respectively). Left ventricular end-diastolic volume index was significantly less in the patients (44.9 +/- 9.7 ml/m2) than in the normal subjects (68.9 +/- 13.1 ml/m2). There was no significant difference in left ventricular end-systolic volume between the two groups (24.4 +/- 8.6 and 27.1 +/- 7.8 ml/m2, respectively). Right and left ventricular ejection fractions in the patients with primary pulmonary hypertension (0.43 +/- 0.21 and 0.46 +/- 0.15, respectively) were significantly less than values in normal subjects (0.59 +/- 0.09 and 0.6 +/- 0.11, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Direct quantitation of right and left ventricular volumes with nuclear magnetic resonance imaging in patients with primary pulmonary hypertension. 159 46

Cor pulmonale is present in 54-64% of patients with respiratory failure (mean PaO2: 52-54 Torr) receiving home oxygen therapy in Japan. This may imply that the development of clinical symptoms of cor pulmonale in the course of the disease more strongly reflects far advanced stage than the presence of respiratory failure. In this paper, clinical data from subjects with various forms of precapillary pulmonary hypertension were analysed with respect to correlation between the prognosis and the pulmonary vascular response to various therapeutic modalities such as acute administration of oxygen, vasodilator drugs, and surgery. The results were as follows: 1) In subjects with COPD, there was a significant correlation between mean pulmonary arterial pressure (PPA) and prognosis. Patients who showed decreased pulmonary vascular resistance (% delta PVR less than -10) after 100% oxygen inhalation had a good prognosis. 2) In subjects with sequelae of pulmonary tuberculosis, there was no apparent correlation between the prognosis and % delta PVR after 100% oxygen inhalation. 3) In subjects with both COPD and sequelae of pulmonary tuberculosis, the lowest value of desaturation during sleep was significantly correlated to the PPA during wake. 4) Analysis of 232 cases with primary pulmonary hypertension revealed the following prognostic factors: PPA, cardiac output, stroke volume index, pulmonary vascular resistance, mixed venous oxygen tension, right atrial pressure, total bilirubin, and total protein.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Clinical aspects of precapillary pulmonary hypertension]. 162 93

The purpose of this study is to assess the right atrial and ventricular function by radionuclide ventriculography using continuous infusion of 81mKr in normal subjects and in patients with heart disease. 1) Reproducibility of RVEF measurement by continuous infusion of 81mKr was good (interobserver; gamma = 0.97, p less than 0.001, n = 20: intraobserver; gamma = 0.97, p less than 0.001, n = 20). This method had a excellent correlation with RVEF of 99mTc first-pass technique (gamma = 0.92, p less than 0.001, n = 20). 2) RVEF was measured in 10 normal volunteers, 76 patients with myocardial infarction (OMI), 20 patients with dilated cardiomyopathy (DCM), 5 patients with arrhythmogenic right ventricular dysplasia (ARVD) and 5 patients with primary pulmonary hypertension (PPH). In OMI and DCM, their RVEF was lower than that of normal volunteers and, in ARVD and PPH, lower than that of OMI and DCM. There was a significant inverse correlation between RVEF, mean pulmonary artery pressure and right ventricular end-diastolic volume index. 3) The effect of the location of right coronary artery (RCA) lesions on RVEF during exercise was also evaluated. Ten normal volunteers and 27 patients with OMI were studied at rest and during exercise. The patients with OMI were divided into two groups: those without proximal RCA lesions (non RCA group, n = 12) and those with proximal RCA lesions (RCA group, n = 15). Although there were no significant increases of RVEF during exercise in both group, the percent change in RVEF was less in RCA group than in non RCA group. These findings suggested that proximal RCA stenosis is a major determinant of exercise RVEF. 4) To assess the right atrial function, right atrial volume curve was measured in 10 normal volunteers, 32 patients with OMI and 4 patients with PPH. The curve was clearly divided into 4 phase; filling phase (312 +/- 40 msec), early ejection phase (276 +/- 53 msec), plateau an index of right atrial reservoir function, was 0.41 +/- 0.05 and Contractile Volume/Stroke Volume (Contr. V/SV), as an index of right atrial pump function, was 0.23 +/- 0.05 in normal volunteers. In OMI and PPH, atrial reservoir function decreased and atrial pump function increased. It was concluded that radionuclide ventriculography using continuous infusion of 81mKr was useful to assess the right heart function.
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PMID:[Assessment of right atrial and ventricular function by radionuclide ventriculography using continuous infusion of 81mKr]. 206 Sep 2

Eight patients with primary pulmonary hypertension underwent systolic time intervals, M-mode echocardiography, and direct hemodynamic studies in order to determine the correlation between noninvasive parameters and hemodynamic variables and to evaluate the utility of these noninvasive studies in primary pulmonary hypertension. The ratio of the pre-ejection period to left ventricular ejection time (PEP/LVET) of the systolic time intervals was abnormally increased (greater than 0.42) for each subject; the increase in the PEP/LVET was secondary to a shortening of the left ventricular ejection time in four patients, prolongation of the pre-ejection period in one, or a combination of such, noted in three patients. In contrast, echocardiographic parameters of left ventricular function, specifically percent change in the minor axis of the left ventricle with systole, velocity of circumferential fiber shortening, and ejection fraction, were normal. In addition, a very good correlation was noted between PEP/LVET and total pulmonary resistance (r value = -0.89, p less than 0.05), while the echocardiographic parameters correlated well with stroke volume and cardiac output (r values ranged from 0.68 to 0.72, p less than 0.05). These results indicate that in primary pulmonary hypertension, the performance of both systolic time intervals and M-mode echocardiography noninvasively provides useful information concerning the hemodynamic status of these patients. Systolic time intervals provide an estimation of overall cardiac-cardiovascular performance, rather than left ventricular function alone, which in turn, is validly examined by M-mode echocardiography.
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PMID:Combining left ventricular systolic time intervals and M-mode echocardiography in the evaluation of primary pulmonary hypertension in women. 315 4

Seven women with primary pulmonary hypertension underwent hemodynamic evaluation, at rest and during exercise, before and after the oral administration of captopril. Dose-response curves were generated for the 25-, 50- and 100-mg doses. Captopril significantly reduced systemic blood pressure and systemic vascular resistance; these effects persisted at submaximal levels of exercise. Captopril did not alter pulmonary artery pressure or resistance, cardiac output or stroke volume at rest or during exercise. Exercise tolerance did not improve. Four of the patients also received captopril chronically for 12 weeks at doses of 75 and 100 mg every 8 hours. Resting and exercise hemodynamic evaluation was repeated at the end of the 12-week period. Except for a persistent reduction in mean systemic blood pressure at rest, chronic captopril administration did not elicit hemodynamic changes. Measured exercise duration did not change during continuous captopril treatment, although one patient reported mild subjective improvement in activity tolerance. In primary pulmonary hypertension, captopril exerts its major effect on systemic vasculature, with little or no effect on the pulmonary circuit. While an occasional patient may experience some clinical improvement with captopril therapy, the majority of adult patients with severe primary pulmonary hypertension will not benefit from its chronic administration.
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PMID:Captopril in primary pulmonary hypertension. 633 5

8 patients with moderate to severe primary pulmonary hypertension underwent systolic time intervals, M-mode echocardiography, and direct hemodynamic studies in order to determine the correlation between noninvasive parameters and hemodynamic variables and to evaluate the utility of these noninvasive studies in primary pulmonary hypertension. The ratio of the pre-ejection period to left ventricular ejection time (PEP/LVET) of the systolic time intervals was abnormally increased (greater than 0.42) for each subject; the increase in the PEP/LVET was secondary to a shortening of the left ventricular ejection time in 4 patients, prolongation of the pre-ejection period in 1, or a combination of such, noted in 3. In contrast, echocardiographic parameters of left ventricular function, specifically, percent change in the minor axis of the left ventricle with systole, velocity of circumferential fiber shortening, and ejection fraction, were normal. In addition, a very good correlation was noted between PEP/LVET and total pulmonary resistance (r value = -0.89), while the echocardiographic parameters correlated well with stroke volume and cardiac indices (r values ranged from 0.68 to 0.72). These results indicate that in primary pulmonary hypertension, systolic time intervals provide an estimation of overall cardiac-cardiovascular performance, rather than left ventricular function alone, which in turn, is validly examined by M-mode echocardiography.
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PMID:Combined systolic time intervals and M-mode echocardiography in the evaluation of central hemodynamics in primary pulmonary hypertension. 647 24

The effects of 3 types of vasoactive agents, hydralazine, nifedipine and amrinone, were evaluated in 7 patients with primary pulmonary hypertension (PPH). Hemodynamic values were measured before and after drug administration in every patient. All drugs increased cardiac output and reduced both systemic and pulmonary resistance in the patients studied. Only nifedipine significantly reduced pulmonary artery (PA) pressure (6 +/- 5 mm Hg). In addition, it decreased pulmonary resistance to a greater degree than systemic resistance in 2 of the 7 patients, suggesting that nifedipine can cause selective pulmonary vasodilation in some patients. Hydralazine appeared to increase cardiac output and stroke volume by reducing systemic resistance. There was no evidence of direct pulmonary vasodilating effects; it decreased systemic resistance more than pulmonary resistance in every case. The increase in cardiac output from amrinone was secondary to a decrease in systemic arterial pressure with reflex tachycardia; stroke volume was unchanged. Amrinone had little pulmonary effect in all but 1 patient, in whom it substantially reduced PA pressure and pulmonary resistance. The mechanism of action of these 3 drugs in PPH differs. Nifedipine holds the most promise as an effective pulmonary vasodilator. A study of the effects of long-term administration of nifedipine in PPH is warranted.
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PMID:Comparative actions of hydralazine, nifedipine and amrinone in primary pulmonary hypertension. 663 31

Primary pulmonary hypertension is considered a fatal illness, with survival typically of less than four years, although survival of more than 10 years has been well documented. To assess the characteristics of patients with primary pulmonary hypertension who survive versus those who do not, 12 patients with primary pulmonary hypertension were followed, and their clinical course was documented with serial catheterization. The survivors, four male and three female, had their illness for a mean of 5.2 +/- 2 years from the time of initial catheterization, with six of the seven alive at the end of the follow-up period. The five nonsurvivors, all female, had a mean survival of 0.3 +/- 0.2 years. The nonsurviving group had significantly higher right atrial pressures (17 +/- 6 versus 6 +/- 2 mm Hg), lower cardiac indexes (1.2 +/- 0.1 versus 2.3 +/- 0.5 liters/minute/m2) and stroke volume indexes (12 +/- 7 versus 30 +/- 5 ml/beat/m2), and higher systemic resistances (64 +/- 13 versus 43 +/- 14 units) and pulmonary resistances (57 +/- 31 versus 20 +/- 4 units). The pulmonary artery pressure did not significantly differ between the groups. Using regression analysis, it was found that stroke volume index and right atrial pressure were the best independent predictors of survival, with a coefficient of determination (r2) of 83 and 72, respectively. When the initial and most recent catheterization data were compared among the survivors, no significant differences were found. Determining the stroke volume index and right atrial pressure of patients with primary pulmonary hypertension at the time of their initial presentation should help in predicting their clinical course.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Characteristics of surviving and nonsurviving patients with primary pulmonary hypertension. 671 71


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