Laminin localization and gelatinolytic activity of epithelial rest of Malassez grown on titanium

The purpose of this study was to examine laminin localization in epithelial rests of Malassez grown on titanium and their gelatinase activity. Laminin localization was confirmed by immunocytochemistry in all epithelial cells grown on titanium. The conditioned medium from the epithelial cells grown on titanium exhibited 72kD- and 92 kD-gelatinase activities by gelatin zymography. Those results suggest that laminin contributes to the epithelial cell attachment to titanium and that gelatinases may be mobilized for epithelial cell movement on titanium.

Amperometric glucose sensors based on immobilized glucose oxidase-polyquinone system

Non-cross-linked and also cross-linked poly(ether amine quinone)s were prepared and tested for their efficiency as electron-transfer relay systems in amperometric glucose biosensors. Cyclic voltammetry and constant applied potential measurements showed that poly(ether amine quinone) relay systems efficiently mediated electron transfer from reduced glucose oxidase to a conventional carbon paste electrode. Sensors containing these relay systems respond rapidly to low (< 0.1 mM) glucose concentrations and reach steady-state current responses in less than 1 min. Electrodes constructed with cross-linked polymer and glucose oxidase were stable, indicating that the glucose oxidase was trapped in the polymer matrix and did not freely diffuse away from the electrode surface into aqueous solutions. The cross-linked polymer is a large molecular system which facilitates a flow of electrons from enzyme to the electrode, acting as an electron-transfer relay system and not as a diffusional mediator.

Effect of sustained release diltiazem (Diltiazem-R) in patients with stable effort angina

Ca++-antagonist is effective not only for variant angina but also for effort angina. The effects of sustained release diltiazem (diltiazem-R) and beta 1-blocker (atenolol) on exercise tolerance were studied in seven patients with stable effort angina in a cross over trial. Diltiazem-R (100mg) or atenolol (50mg) was given once a day, each treatment period lasting for two weeks after a two-week control period. The treadmill exercise test was performed on the last day of each protocol. Both diltiazem-R and atenolol decreased heart rate at rest and the decrease with atenolol was greater than that with diltiazem-R. The systolic blood pressure was unchanged at rest by both drugs. At maximal work levels, atenolol decreased the heart rate and pressure rate product significantly but diltiazem-R did not. Both diltiazem-R and atenolol significantly prolonged the exercise time (average 137 and 165 seconds respectively), time to onset of 1mm ST depression (240 and 288 seconds respectively). There was no significant difference in exercise tolerance between diltiazem-R and atenolol. These findings suggest that diltiazem-R, a sustained release Ca++-antagonist, provides beneficial effects in patients with stable effort angina.

[Long-term follow-up study after permanent pacemaker implantation in patients aged 60 years or over with sick sinus syndrome]

Ninety-five patients aged 60 years or over with a permanent pacemaker implanted for sick sinus syndrome were divided into two groups: 32 patients with physiological pacing (group P) and 63 patients with ventricular pacing (group V). The mean follow-up period was 45.0 +/- 36.6 months in group P and 50.3 +/- 37.8 months in group V. Paroxysmal atrial fibrillation (Af) occurred in 28% of group P and 71% of group V (p < 0.05). The incidence of stable Af was also lower in group P than in group V (9% vs. 30%, p < 0.05). None of group P with only bradyarrhythmia had stable Af. However, 6 of 21 patients (29%) in group V with bradyarrhythmia showed stable Af. There was no significant difference in stable Af between group P with bradycardia-tachycardia syndrome (BTS) and group V with BTS (19% vs. 31%). A lower incidence of embolic events was also observed in group P (3% vs. 25%, p < 0.05). Nine of 16 patients with embolic events in group V died of complications following embolism (8 patients; cerebral embolism, one patients: renal and superior mesenteric arterial embolism). The survival rates at 5 and 10 years were 80% and 69%, respectively, for group P and 56% and 33% for group V (p < 0.01). Thus, with regard to permanent pacing for patients with sick sinus syndrome, physiological pacing should be selected for control of morbidity and total mortality.

Association of endometrial epithelial metaplasias with endometrial carcinoma and hyperplasia in Japanese and American women

We reviewed endometrial tissue from 166 cases of endometrial adenocarcinoma and hyperplasia--91 seen at Kyushu University, Fukuoka, Japan, and 75 at George Washington University, Washington, D.C., U.S.A.--to compare the prevalence of epithelial metaplastic changes in the two populations. Metaplasias were more common in the benign endometrium associated with carcinoma at George Washington University (78%) than at Kyushu University (54%). They were associated with carcinomas of lower grade and accompanied by hyperplasia at both institutions. These results indicate that endometrial metaplasias, like endometrial hyperplasias, tend to be associated with less virulent endometrial carcinomas and to be more common in American women (who represent a high-risk population for endometrial carcinoma) than in Japanese women (in whom the risk is low but rising.

Ovarian mucinous cystadenocarcinoma with sarcoma-appearing mural nodule of anaplastic carcinoma

An ovarian mucinous cystadenocarcinoma with sarcoma-appearing solid mural nodules in an 18-year-old Japanese woman is reported. Right ovarian cyst had two poorly circumscribed, solid nodules and several tiny studs. Microscopically, the epithelial elements consisted of benign, low malignant potential and malignant mucinous tumors. The mural nodules were made up of highly malignant anaplastic cells simulating sarcoma. In one of the mural nodules, continuity between the malignant mucinous cells and sarcoma-appearing cells was identified. Immunohistochemically, the sarcoma-appearing nodule was uniformly positive for vimentin and focally positive for epithelial markers such as EMA, CAM5.2, and AE1/AE3. This case demonstrated an orderly transformation and dedifferentiation of epithelial cells to undifferentiated mesenchymal cells. Although she had stage IIb disease, she lived disease free for 3 years and 5 months after surgery followed by 10 courses of chemotherapy containing cisplatin and Adriamycin.

Histopathologic prognostic factors in stage IIb cervical carcinoma treated with radical hysterectomy and pelvic-node dissection - an analysis with mathematical statistics

Of 107 patients with stage IIb cervical cancer who underwent laparotomy, 82 (77%) could be treated with radical hysterectomy (RAH) and pelvic-node dissection (PND). The remaining 25 patients were unsuitable for radical surgery because of para-aortic lymph node metastases, direct cancer invasion into the bladder muscle, and/or fixed enlarged pelvic lymph nodes (PLN): Such patients were treated with radiation therapy after laparotomy. Fifty-nine of RAH patients were given postoperative pelvic radiation because they had PLN metastases, parametrial invasion, and/or full thickness cervical stromal invasion. The overall 5-year survival of the patients undergoing RAH was significantly better than that of those who could not be treated with RAH (P < 0.001). In the RAH patients, parametrial invasion, which clinically defines stage IIb, was found only in 45%. Univariate analysis of histopathologic prognostic factors revealed that PLN metastasis, parametrial invasion, adenocarcinoma, and lymph-vascular space invasion significantly affected survival of the RAH patients (P < 0.05). Multivariate analysis using Cox's proportional hazards regression model, however, selected only PLN metastasis as a strong prognostic factor (P < 0.001). Concerning PLN metastasis patients with two or more positive nodal groups vs. 49%, P < 0.0001). The logistic regression analysis revealed that tumor diameter, parametrial invasion and lymph-vascular space invasion were independently correlated with PLN metastases in two or more nodal groups. The present data suggest that (i) the patients with massive pelvic extension of cancer cannot be cured by radiation therapy alone, (ii) the strong determinant of the prognosis of the patients undergoing RAH and PND is PLN metastasis. Therefore, for these patients with poor prognosic factors, other treatment modalities should be considered. From the present study it seems that planning RAH and PND for patients with stage IIb disease might make it possible to select poor prognostic subgroups, who have extra cervical extension or PLN metastases in two or more groups, and be useful in individualizing treatment.

Pharmacokinetics of flosequinan in elderly patients with chronic congestive heart failure

We have investigated the pharmacokinetics of the direct vasodilator flosequinan in elderly patients with congestive heart failure. Eight patients received a single dose of 50 mg, and 8 patients received once-daily treatment with 25 mg for two weeks. In the single dose study, the tmax of flosequinan was 2.5 h, Cmax was 1.17 microgram.ml-1 and t1/2 was 5.63 h. The tmax of the metabolite BTS 53554 was 20.3 h, Cmax was 1.44 microgram.ml-1 and t1/2 was 62.0 h. BTS 53554 accumulated gradually in the 14-day repeated dose study and steady-state was reached after approximately 2 weeks. Flosequinan was not found to accumulate. Adverse reactions were not observed in either the single or repeated dose study. It is advisable to consider renal function and body weight when flosequinan is to be administered to elderly patients with congestive heart failure. The initial dose should be 25 mg.

Endometrial carcinoma in women aged 40 years or younger: a Japanese experience

We report on the clinical and pathologic findings in 17 cases of endometrial carcinoma in Japanese women aged 40 years or younger. Age of the patients ranged from 16 to 40 years, with a median of 35 years. Nine of 17 tumors (52.9%) were stage I or II (FIGO 1988) but 8 (47.1%) were stage III. Four of the 8 patients with stage III disease had pelvic lymph node metastases and one also had para-aortic lymph node metastasis. One patient had metastasis to the ovary and peritoneal cytology was positive in 4 patients. Histologically, 13 of these 17 patients had endometrioid adenocarcinoma, 3 had adenoacanthoma and 1 had an undifferentiated carcinoma. Ten were well differentiated tumors (G1), 3 were moderately differentiated tumors (G2), and 4 were poorly differentiated tumors (G3). Nine of 17 (52.9%) showed deep myometrial invasion (more than a half of the myometrium) and 5 of 17 (29.4%) demonstrated lymphatic/vascular space invasion. Pelvic and para-aortic lymph node metastases were seen in 4 of 15 (26.7%) and 1 of 15 (6.7%), respectively. Two of these 17 patients died of disease in a relatively short follow-up period. In our experience there is no difference in the survival rates between patients aged 40 years or younger and those over 40 years.

[Alterations of hemostatic markers in elderly patient with atrial fibrillation without a history of stroke]

To evaluate whether hemostatic abnormalities contribute to the increased risk of stroke, the authors prospectively studied the hemostatic markers (HM) (beta-TG, PF4, FPA, TAT, PIC, D-dimer) in 34 elderly patients with atrial fibrillation (Af) without a history of stroke (mean age 79.2) and 14 age-matched controls. In the Af group FPA was significantly higher than in the control group (p < 0.05). Among them, 8 patients showed a similar abnormal HM pattern as in cardioembolic is chemic stroke and in these, 4/8 patients had valvular disease (VD), 2/8 had hypertension (HT), 2/8 had congestive heart failure (CHF), 1/8 had diabetes mellitus (DM) and 1/8 had hyperlipidemia (HL). Eight patients showed the same abnormal HM pattern as atherothrombotic is chemic stroke and of these, 2/8 had HT as complications. Five patients showed combination of a HM abnormal pattern, that was observed in cardioembolic and atherothromboic ischemic stroke. The other 13 patients showed a normal HM pattern, were in these patients, 4/13 had HT, 1/13 had DM, 1/13 had VD, and 1/13 had CHF. The patients with VD complication tended to have embolic HM abnormality. Contrary to previous reports, nonvalvular Af patients do not necessarily tend to have high risk of cardioembolic stroke. Our data suggest difficulties in clinical diagnosis among Af patients with ischemic stroke whether it is cardio embolic or atherothrombotic.

Relationship between paraaortic lymph node involvement and intraperitoneal spread in patients with ovarian cancer--a multivariate analysis

In 125 patients with epithelial ovarian cancer (FIGO stages I-IV), 32 (26%) had paraaortic lymph node (PAN) metastases. The estimated 5-year survival rate of PAN-negative patients was 71%, while that of PAN-positive patients was 17% (P < 0.0001). Positive rates of PAN metastasis at each stage level, based only on intraperitoneal spread of the disease, were 2% for stage I, 9% for stage II, 43% for stage III, and 87% for stage IV. According to univariate analysis, histological grade, and all disease site parameters examined, such as subdiaphragmatic surface, liver and spleen capsule, intestines and mesentery, omentum, pelvic peritoneum, sigmoid colon and rectum, uterus and tubes, and peritoneal cytology, showed a statistically significant correlation to the presence of PAN metastasis. Multivariate analysis using the logistic regression model revealed that the omental involvement, uterine and tubal involvement, and histological grade were independently correlated with PAN metastasis. The relative risk of PAN metastasis in the patients with these three factors is 18.5 times higher than that in patients without these factors. The present data suggested that, for the disease with omental and/or uterine and tubal involvement, surgical evaluation of PAN is mandatory in order to perform correct FIGO staging.

Expression of alpha-smooth muscle actin in benign or malignant ovarian tumors

We compared the expression of alpha-smooth muscle actin (alpha-SMA) between benign and malignant human ovarian tissues by immunohistochemical staining and Western blot analysis using the monoclonal antibody specific to alpha-SMA. In normal human ovaries, alpha-SMA was found in the blood vessel walls, muscle fibers, and stromal cells surrounding the follicles. The main source of alpha-SMA in the benign ovarian tumors was the blood vessel walls which highly expressed the alpha-SMA throughout the tumor. In malignant tumor tissues, however, the vessels located in or close to the cluster of cancer cells did not express alpha-SMA. It corresponded to the results of the Western blot analysis, showing that the amount of alpha-SMA in malignant ovarian tumor tissues was much smaller than that in benign tumor tissues. Thus, the alteration in alpha-SMA expression seems to reflect the qualitative difference in vessels between benign and malignant ovarian tissues, and therefore alpha-SMA is considered to potentially be a histopathologically useful marker for indicating the malignant potential of ovarian tumors.

Large cyst formation in pleomorphic adenoma

The aim of this study was to examine about the etiology of large cyst formation in pleomorphic adenoma from the histopathological standpoint by examining four cases of our own as well as previously reported ones. In the first of our cases, a large cyst wall lined with keratinized squamous epithelium was observed. In the second, a large cyst containing mucinous material was lined with a single cell layer of squamous epithelium-like cells. The third case was a carcinoma in pleomorphic adenoma with some large cysts lined with multiple layers of atypical epithelial cells. In the fourth case, a hemorrhagic portion were seen on a large cyst wall without a lining of epithelial cells. From these histopathological observations and the suggestions of previous authors, we surmised that the large cyst formation in pleomorphic adenoma might originate from the squamous metaplasia of tumor cells and the enlargement of duct-like structures by outstanding secretion from tumor cells or salivary gland tissues, hemorrhagic portions, or necrosis in the malignant tumor.

Microcarcinoma of the endometrium: a mapping study with special reference to cytologic atypia in the endometrium

In order to elucidate the basis for the development of an endometrial carcinoma, we looked for microcarcinomas measuring < 5 mm in greatest diameter, and studied their histologic characteristics and those of the neighboring endometrium. Using serial step section methods, two microcarcinomas were detected. A microcarcinoma was found in one of 14 uteri resected for atypical hyperplasia and the other was found in one of 114 uteri resected for endometrial carcinoma. The neighboring endometrium of the former was adenomatous and had atypical hyperplasia and that of the latter was atrophic and contained atypical glands characterized by cytologic atypia and not by architectural changes. The findings may suggest endometrial carcinomas to have two pathogenetic forms: a carcinoma associated with hyperplasia and occurring in premenopausal women, a second carcinoma associated with atrophic endometrium and occurring in postmenopausal women. Atypical glands in atrophic endometria may indicate that endometrial specimens from postmenopausal women should be carefully screened for cytologic atypia.

Endometrial metaplasia associated with endometrial carcinoma

OBJECTIVE

To clarify the relationship of metaplasia to endometrial carcinoma.

METHODS

Between 1984-1990, 73 cases of stage I-II endometrial carcinoma treated initially by hysterectomy were reviewed histologically. The metaplasias were classified as squamous, syncytial papillary, ciliated-cell, eosinophilic, mucinous, clear-cell, or hobnail. We assessed the histologic type and grade of the carcinoma, depth of myometrial invasion, presence or absence of lymph-vascular space invasion, and presence or absence of lymph node metastases.

RESULTS

Forty of 73 patients (55%) had one or more areas of metaplasia in the endometrium adjacent to the carcinoma. Ciliated-cell metaplasia (28 of 73; 38%) was the most common type encountered. Women with both endometrial carcinoma and metaplasia were significantly younger than those with carcinoma without metaplasia (P < .05). Compared with carcinomas without metaplasia, those with metaplasia were well differentiated (P < .01) and lacked myometrial invasion (P < .01) and pelvic lymph node metastases (P < .05). The presence of metaplasia was also significantly correlated with the presence of endometrial hyperplasia (P < .01).

CONCLUSION

In endometrial carcinomas, the presence of endometrial metaplasia suggests a favorable prognosis.

Mutual recognition between polymerized liposomes. IV. Polysaccharide-lectin system

As a model of cell-cell recognition processes, the association processes of a polysaccharide (mannan)-carrying liposome with a lectin (Concanavalin A, Con A)-carrying polymerized liposome were followed by turbidimetry. The association process was strongly inhibited by the addition of a low molecular weight sugar, methyl-alpha-D-mannopyranoside, which shows that the association between the liposomes is due to the specific interaction between Con A and mannan. The association rate constant obtained was much smaller than the theoretical value for a diffusion-controlled binary association process. This implies that the association rate of liposomes is limited by the recognition between complementary ligands bound on the liposome surfaces. Another reason for the smaller association rate constant in the liposome-liposome system is the repulsive hydration effect. The effect of the surface density of the lectin immobilized on the liposome on the recognition was also examined.

[Visuo-postural control of schizophrenics--variations of sway area during horizontal eye movement]

In the present study, we investigated the neurological mechanism of commonly known specific or unnatural postures in schizophrenic patients. Using a gravimeter, body sway studied in 26 chronic schizophrenic patients, 10 schizoaffective disorder patients and 21 normal subjects. During eye fixation at a target while keeping an upright posture, schizophrenic patients presented a larger gravimetric area than the normal subjects and the patients with schizoaffective disorder. There was a negative correlation (r = -0.509) between the standard deviation of the sway gravimetric area during fixation and the dose of neuroleptics in schizophrenic patients, but no correlation was found in patients with schizoaffective disorder (r = -0.01), although they took neuroleptics in a similar regimen to that for the schizophrenics. There was no correlation between the standard deviation of the sway gravimetric area during fixation and the duration of illness. There was also no correlation between the former and the amplitude ratio of saccades during smooth pursuit eye movements. When horizontal eye movements pursuing the target were loaded in this experiment, both the normal subjects and the patients with schizoaffective disorder showed a decrease in a loaded gravimetric area and a tendency towards postural stabilization. However, schizophrenic patients having higher SANS scores (Andreasen) presented an increase in gravimetric area. This suggests that schizophrenic patients with higher SANS score may have organic cerebellar changes related to impairment of the mechanism of visual and postural coordinations.

Ruptured chordae tendineae in acromegaly. An autopsy case

A 57-year-old woman with acromegaly associated with mitral chordal rupture is reported. She was noted to have abnormal development in the size of her hands and feet in childhood. She occasionally suffered from shortness of breath on exertion and nocturnal dyspnea for several years, and was diagnosed and treated as having congestive heart failure due to valvular heart disease. On admission to our hospital, chordal rupture was suspected on the basis of M-mode and two-dimensional echocardiography. Seven years after discharge, she died of congestive heart failure. On autopsy, the heart weight and ventricular wall thickness were increased. Rupture of the posterior chordae was confirmed, but evidence of an old myocardial infarction was not found. There was severe interstitial fibrosis in the left ventricular wall. A possible etiology of the chordal rupture in this case was thought to be the excessive stretching caused by the disproportional visceromegaly of the heart.

Changes in sodium-22 turnover and total body potassium in two-kidney, one-clip renovascular hypertension

Changes in sodium-22 turnover and total body potassium (TBK) were studied during acute (within 2 weeks after clipping) and chronic (12-14 weeks after clipping) phases in two-kidney, one-clip (2k, 1c) hypertensive rabbits by using a whole body counter. Sodium-22 injected intravenously was eliminated more rapidly in hypertensive rabbits than in controls. The biological half-life (BHL) of sodium-22 was shorter in hypertensive rabbits during both acute (p less than 0.05) and chronic phases (p less than 0.001). A significant negative correlation was obtained between the BHL of sodium-22 and blood pressure (r = -0.588, p less than 0.05) in hypertensive rabbits. TBK decreased significantly at the chronic phase in hypertensive rabbits (p less than 0.05), while TBK showed no significant change in controls. Serum sodium and potassium did not change during the observation period. Increased plasma aldosterone concentration was observed during the acute phase in hypertensive rabbits. These results suggested that sodium retention was not a major factor in the acute and chronic phases of 2k, 1c hypertension in rabbits and that pressure natriuresis could explain, at least in part, the lack of sodium retention. Furthermore, there appears to be a derangement in the intracellular potassium metabolism which may be associated with the maintenance rather than the development of hypertension.

[Dry cough in the elderly patients treated with angiotensin converting enzyme inhibitor]

Since dry cough has recently been recognized as a side effect of angiotensin converting enzyme (ACE) inhibitors employed in the treatment of hypertension or congestive heart failure, the incidence of dry cough in elderly patients receiving ACE inhibitors was investigated. There were 237 out-patients on either captopril, enalapril, or delapril, in August and November 1989. Questionnaires concerning dry cough and smoking were completed by 184 patients. Patients either less than 50 years of age, or with chronic pulmonary disease were excluded. The remaining 168 patients, 63 males, 105 females, with a mean age of 73 years were analyzed for the incidence of a dry cough in relation to age, sex, smoking, and type of drugs. The overall incidence of a dry cough was 21/168 (12.5%), 7/63 (11.1%) for males and 14/105 (13.3%) for females, and was less frequent with advancing age; in the 51-60 age group 4/11 (36.4%), in the 61-70 age group 5/39 (12.8%), in the 71-80 age group 9/75 (12.0%), in the 81-90 age group 3/40 (7.5%), in the 91- age group 0/3 (0%). Enalapril showed significantly higher incidence of dry cough than captopril (16/93, 17.2% vs 7/88, 8.0%, p less than 0.05). Delapril showed an incidence 4/11, 36.4%, however, 9 out of the 11 patients who were given delapril had had a history of a dry cough with captopril or enalapril, and in 4 out of these 9 patients the dry cough disappeared by replacement of captopril or enalapril by delapril.(ABSTRACT TRUNCATED AT 250 WORDS)

Microscopic ovarian metastasis of the uterine cervical cancer

Six hundred forty-seven cases of carcinoma of the uterine cervix with FIGO stages Ib or more were initially treated with hysterectomy at Kyushu University Hospital from 1973 to 1987. In these, 597 cases could be pathologically reviewed for ovarian metastasis. In these 597 cases, 335 were stage Ib, 71 IIa, 185 IIb, and 6 IIIb. Only 3 (0.5%) of 597 showed ovarian metastasis. All 3 cases were stage IIb. None of stage Ib cancer cases had ovarian metastasis. One (0.19%) of 524 squamous cell carcinomas metastasized to the ovary, whereas 2 (5.5%) of 36 pure adenocarcinomas revealed ovarian metastasis. Interestingly, all ovarian metastatic lesions were microscopic in size and found in the ovarian hilus. As for the primary lesion, all cases with ovarian metastasis showed deep myometrial invasion, corpus invasion, and lymphatic permeation. Two cases showed pelvic lymph node metastases and positive peritoneal washing cytology. From the results of our study, it can be said that it is fairly safe to preserve the ovary at the time of radical operation in squamous cell carcinoma of the uterine cervix, but it may not be safe to preserve the ovary in pure adenocarcinoma of the uterine cervix.

Alpha-adrenergic regulation of phosphoinositide metabolism and protein kinase C in isolated cardiac myocytes

alpha 1-Adrenergic regulation of phosphoinositide metabolism and protein kinase C translocation was studied in isolated rat cardiac myocytes. Exposure of [3H]inositol-labeled myocytes to norepinephrine in the presence of propranolol caused a dose-dependent increase in [3H]inositol phosphates. Norepinephrine also increased the level of membrane-associated protein kinase C from approximately 10% of total activity to 18%, with a dose response similar to that for generation of inositol phosphates. Depolarization of myocytes with 30 mM KCl had no effect on inositol phosphates or membrane-associated protein kinase C but potentiated the effect of submaximal norepinephrine on both parameters. The potentiation of protein kinase C translocation was amplified when extracellular Ca2+ was increased to 4 mM, resulting in membrane association of one-third of the total cellular activity. These data show that activation of protein kinase C occurs during alpha 1-adrenergic stimulation of cardiac myocytes and that elevation of intracellular Ca2+ amplifies this effect at least in part through increased phosphoinositide metabolism.

Reflection as a cause of mid-systolic deceleration of pulmonary flow wave in dogs with acute pulmonary hypertension: comparison of pulmonary artery constriction with pulmonary embolisation

STUDY OBJECTIVE

The aim was to examine whether mid-systolic deceleration of the pulmonary flow wave occurred in acute pulmonary hypertension due to pulmonary artery constriction and pulmonary embolisation, and if so whether it was related to reflection.

DESIGN

Various degrees of pulmonary hypertension were induced by both pulmonary artery constriction and pulmonary embolisation in dogs. During control periods and during pulmonary artery constriction and pulmonary embolisation, pulmonary flow and pulmonary artery pressure were recorded, and the forward and backward (reflected) flow waves were separated from the measured pulmonary flow wave by the method of Westerhof et al.

MATERIALS

20 adult mongrel dogs were used and 10 dogs qualified for analysis. The other 10 dogs, which died before both interventions were completed, were excluded.

MEASUREMENTS AND MAIN RESULTS

During pulmonary artery constriction, a distinct mid-systolic deceleration of the pulmonary flow wave was observed in five of the 10 dogs, while during pulmonary embolisation, no mid-systolic deceleration was found in these five dogs. The distinct deceleration of the pulmonary flow wave was related to a steep fall and early negative peak in the backward flow wave.

CONCLUSION

Mid-systolic deceleration of pulmonary flow wave is likely to be related to reflection.