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At least 451 records · Page 25Linked to original sources
PubMed1997

[Acute effusive-constrictive pericarditis in influenza A].

Constrictive pericarditis may complicate the course of several viral infections, mainly Coxsackie virus group B, as well as in rheumatoid disease, radiation and neoplasm. Perimyocardial involvement during influenzal infections is usually mild and does not progress to constriction or tamponade. A single case of cardiac tamponade caused by influenza A was reported in 1986. We report a case of acute effusive-constrictive pericarditis due to influenza A infection. Corticosteroids resulted in some benefit, but did not relieve constriction, which required extensive pericardiectomy.

Adolescent↗
PubMed1997

[Surgical management of constrictive pericarditis].

Cases of constrictive pericarditis per a institute is few for decrease of this disease. Therefore for surgical management of constrictive pericarditis, it has not been clear whether cardiopulmonary bypass during operation is necessary or not, and the reports of long term results are few. We gathered information by questionnaires from thirty-four institutes, which constitute Tokai Cardiovascular Surgeons Conference in Shizuoka, Aichi, Mie and Gifu Prefecture, for surgical management of constrictive pericarditis, and investigated its results. Etiology of constrictive pericarditis is idiopathic (49%), tuberculosis (29%) or post open heart surgery (10%). Hospital death included operative death is 14%, and postoperative liver complications was many next to heart complications. The cases, whose NYHA functional class at discharge did not improve compared with preoperative state, was 33%. At one year after operation two third of them improved in NYHA functional class, but the others did not improved.

Adolescent↗
PubMed1994

[Two cases of tuberculous constrictive pericarditis].

Case 1 was a 79-year-old male suspected of tuberculous constrictive pericarditis. He was admitted to our hospital because of surgical treatment. His heart failure was NYHA IV. Culture of pleural effusion and pericardial effusion was negative. But ADA level in pericardial effusion was found to be increased. So tuberculosis was suspected. Cardiac catheterization date was compatible with constrictive pericarditis. Case 2 was a 73-year-old female. She was admitted because of heart failure (NYHA IV). As RVP wave indicated dip & platou at cardiac catheterization, she was diagnosed as constrictive pericarditis. ADA level in pleural effusion increased. So tuberculosis was suspected as etiology of constrictive pericarditis. In both cases, after pericardiectomy, heart failure improved to NYHA I. Results of pathological examination were tuberculous inflammation.

Aged↗
PubMed1997

[The waffle procedure (multiple incision of epicardium) with pericardiectomy for constrictive pericarditis].

Pericardiectomy is the only effective surgical procedure for constrictive pericarditis, but we have often experienced a lack of significant improvement of hemodynamic parameters, this being attributed to the presence of residual constriction. We have had two patients with constrictive pericarditis. In these patients, we decorticated the pericardium as usual, anterior to the bilateral phrenic nerves without cardiopulmonary bypass, and then, multiple longitudinal and transverse incisions were carefully made in the fibrous epicardium, avoiding the predicted course of major coronary branches and the myocardium. At the end of the procedure, the epicardial fibrous surface acquired a waffle-like appearance. With this maneuver, relief of constriction was achieved and the myocardium was able to reexpand, thus obtaining an adequate hemodynamic response. Our two patients recovered fully, and were discharged on the 18th and 19th postoperative day. They are presently free of clinical symptoms.

Aged↗
PubMed1998

[Constrictive pericarditis: an underestimated complication of thoracic injuries].

Constrictive pericarditis is a well defined clinical entity, traditionally secondary to longstanding tuberculosis. Although posttraumatic constrictive pericarditis, due to haemopericardium, is well known during the postoperative period following cardiac surgery, it is underestimated in closed chest trauma. A new case of constrictive pericarditis is reported, due to neglected chest trauma. The discussion emphasizes the need for early diagnosis and surgical treatment, which determine the general prognosis of pericardial constriction. This implies systematic investigation of all cases of chest trauma, even minor, by transthoracic, or preferable, transoesophageal echocardiography, looking for haemopericardium.

Echocardiography, Transesophageal↗
PubMed1998

Constrictive pericarditis presenting as unexplained recurrent pleural effusion: a case report.

Constrictive pericarditis may exceptionally present as pleural effusion of unknown origin and this form of presentation may cause diagnostic problems. We report a case of subacute constrictive pericarditis in which there were recurrent pleural effusion with no other signs of the disease and the initial echocardiographic study was nondiagnostic. For this reason the patient was initially considered to have primary pulmonary or pleural disease. On the basis of the subsequent development of signs of systemic congestion and the results of computed tomography, Doppler echocardiography and cardiac catheterization, which were consistent with constriction, it was concluded that the patient had constrictive pericarditis. A complete resolution of pleural effusion and signs of systemic congestion was observed following pericardiectomy.

Acute Disease↗
PubMed1992

Mesh tube--constricted varicose veins used as bypass grafts for infrainguinal arterial reconstruction.

Varicose veins are generally deemed inappropriate graft material for arterial reconstructions despite their physiologic flow surface because of their large and irregular caliber. Size reduction by threading such veins in constricting tubes may create bypass grafts of suitable caliber as long as redundant wall material does not cause stenoses. Sixteen human varicose veins (mean +/- SD, 13 +/- 3 mm diameter) obtained after stripping operations were inserted into Dacron mesh tubes of 6 mm internal diameter. Paraffin casts of the distended veins showed a size reduction of 6.9 +/- 2.6 mm. Wall material formed folds in only two veins. In both cases, diameter reduction was more than 10 mm. However, the folds did not result in significant stenoses. Mesh-constricted varicose veins were used as bypass material in 11 infrainguinal arterial reconstructions. All externally supported segments showed satisfactory size reduction without stenoses or folds. One graft occluded 2 months after surgery. Two patients had to undergo reoperation after 2 and 16 months, respectively. None of the complications could be attributed to the constriction of veins. The remaining grafts are patent and functional after a mean of 17 months (range, 6 to 42 months). Considerable size reduction by external wrapping of varicose veins is possible without adverse side effects. Such constricted veins were used successfully as bypass grafts for infrainguinal arterial reconstructions.

Aged↗
PubMed1992

Constriction bands and limb reduction defects in two newborns with fetal ultrasound evidence for vascular disruption.

Most structural anomalies attributed to vascular disruption have been inferred, though not proven, to be the result of disruptive events in utero. We report on 2 pregnancies with ultrasound evidence of disruptive events resulting in terminal limb "reduction" defects with constriction bands and other anomalies. In the first patient a fetal ultrasound study at 12 weeks post-LMP demonstrated a monochorionic (MC) twin pregnancy with a nonviable co-twin and no evidence of amniotic bands. At birth, there was a left cleft lip and palate, and terminal limb "reduction" defects with ring constrictions of the left hand and both feet. In the second patient, a routine fetal ultrasound study at 18 weeks post-LMP identified a subhepatic cyst which subsequently resolved. Fetal ultrasound examination and neonatal computed tomography (CT) scan of the liver were consistent with a hepatic infarct due to emboli from the umbilical vein. At birth, patient 2 had acrosyndactyly of the left hand with ring constrictions of the digits and reduction of the left big toe. There was no evidence of abnormal amnion. Postnatal development has been normal in both cases. We present ultrasound evidence supporting the hypothesis that vascular disruption from death of a co-twin or from in utero embolic infarcts can cause: 1) terminal limb "reduction" defects and possibly cleft lip and palate; and 2) ring constrictions similar to those of "amniotic band disruption sequence" in the absence of an abnormal amnion. Serial pregnancy ultrasound studies are recommended for evaluation of the development of fetal structural anomalies following ultrasound evidence of a disruptive event in utero.

Abnormalities, Multiple↗
PubMed2003

Electrophoretic separation and confocal laser-induced fluorescence detection at ultralow concentrations in constricted fused-silica capillaries.

Laser-induced fluorescence detection of labeled amino acids in a flowing stream at femtomolar (10(-15)M) concentrations was achieved by using a fused-silica capillary flow-cell comprising a constricted thin-walled detection region with inner diameters (IDs) ranging from 2 to 8 microm. The diameter of the constricted region was made to match a diffraction-limited focus of a uniphase transverse electromagnetic mode (TEM(00)) laser beam. Optimization of capillary dimensions and geometries (i.e., curvature, wall thickness, and outer-inner diameter ratio were performed in order to minimize cylindrical lensing of the focused laser beam. The fluorescence was collected in a confocal optical setup using a 1.3 numerical aperture (NA), 100x oil-immersion objective and a single-photon-counting avalanche diode (SPAD). Under conditions of fluid flow, the constriction in the capillary forces all analytes to traverse across the laser probe volume, resulting in a high sampling efficiency. Fluorescein isothiocyanate-labeled glutamate (FITC-Glu) was electrophoretically separated and detected in capillaries having an ID of 2 microm at the constricted region with detection limits of 250 fM (signal-to-noise ratio (S/N) = 3) in the injected solution.

Amino Acids↗
PubMed1998

Endothelin-1-induced vasoconstriction causes a significant increase in portal pressure of rat liver: localized constrictive effect on the distal segment of preterminal portal venules as revealed by light and electron microscopy and serial reconstruction.

Intraportal infusion of endothelin-1 (ET-1), a potent vasoconstrictor, significantly elevates portal venous pressure. To determine the major site of vascular constriction in the intrahepatic porto-sinusoidal system, we performed an in situ perfusion of rat livers with 1 nmol/L ET-1 at a flow rate of 20 mL/min. Portal pressure rose from 22 cm H2O to 54 cm H2O within 25 minutes. Specimens were prepared for light-microscopic serial reconstruction and electron microscopy. The distal segment of preterminal portal venules (DS/PPV) with an inner diameter of 40 to 80 microm showed complete obliteration of the lumen over a 300-microm distance caused by the intense contraction of perivascular smooth muscle cells and protruding of endothelial cells into the lumen. The proximal segment of preterminal portal venules (PS/PPV) with a larger diameter up to 150 microm also underwent strong constriction, but still had luminal space for the flow, while the PS/PPV with a diameter of 150 to 400 microm showed moderate or mild constriction and retained a wide lumen. Neither terminal portal venules, inlet venules, sinusoids, nor central veins, however, exhibited demonstrable constriction. Liver parenchyma fed by the inlet venules that emerged from the PS/PPV exhibited a wide sinusoidal lumen and vacuolated hepatocytes caused by the influx of excess portal perfusate that escaped from the occlusive areas. The present study has revealed that the DS/PPV functions as a presinusoidal quasi-sphincter mechanism and is involved in the redistribution of intrahepatic portal flow under increased portal pressure.

Animals↗
PubMed1993

110/140 laminin-binding protein immunoreactivity in spinal dorsal root ganglia: a capsaicin-insensitive reduction induced by constriction injury of the sciatic nerve in rats.

The distribution of 110/140 laminin-binding protein (110/140 LBP) in the spinal dorsal root ganglia (DRG) and its regulation by partial constriction of the sciatic nerve was studied in adult rats. The cross-sectional area of neurons with 110/140 LBP-immunoreactivity (-I) showed an approximately normal frequency distribution. The 110/140 LBP-I was observed in neuronal cell bodies exclusive of the nucleus. Following sciatic nerve constriction, the 110/140 LBP-I was downregulated in the ipsilateral L4-5 DRG. DRG neurons with a cross-sectional area > or = 1600 microns 2 were preferentially affected. Neonatal capsaicin-treatment, a procedure that selectively destroys a subpopulation of DRG neurons with fine unmyelinated axons, had no effect on the reduction of 110/140 LBP in the DRG induced by sciatic nerve constriction. Western immunoblot analysis confirmed a reduction of 110/140 LBP on the side ipsilateral to the constriction. These results demonstrate a LBP within primary sensory neurons and its suppression by peripheral nerve injury. The data support a role for LBP in the adult nervous system.

Animals↗
PubMed2004

Favourable outcome of a tight constriction band secondary to amniotic band syndrome.

Amniotic band syndrome or amniotic disruption complex is a well-known congenital limb abnormality, which occurs in 1 in 1200 to 1 in 15,000 live births. In cases of an isolated band constriction, it has been speculated that the bands lead to decreased blood flow in the constricted limb and subsequent natural amputation. Fetal surgery could be considered in these situations in order to release the constriction band in threatened limb amputation. We present a case of a tight constriction ring secondary to amniotic band syndrome with a favourable outcome, despite the failure of an attempted surgical procedure.

Adult↗
PubMed2004

Congenital constriction band of the upper arm: the role of three-dimensional ultrasound in diagnosis, counseling and multidisciplinary consultation.

Constriction band syndrome represents a sporadic condition that may result in amputations, constrictions and other deformities of the fetal limbs and body. Prenatal diagnosis by two-dimensional ultrasound has been reported. We present a case of constriction band involving the upper arm in which the assessment by three-dimensional ultrasound significantly contributed to the diagnosis and the multidisciplinary counseling. In fact, multiplanar imaging and surface rendering allowed a clear depiction of the extent of the constriction, the club-hand deformity and the relationship between the amniotic band, the cord and the fetal limb. This case represents a unique and effective application of three-dimensional ultrasound in prenatal diagnosis.

Amniotic Band Syndrome↗
PubMed1999

Selective potentiation of angiotensin-induced constriction of skeletal muscle resistance arteries by chronic elevations in dietary salt intake.

Sprague-Dawley rats were fed either a high-salt (HS, 4.0% NaCl) or a low-salt (LS, 0.4% NaCl) diet for 3 days (short-term) or 4-8 weeks (chronic). Vasoconstrictor responses to angiotensin II and norepinephrine were determined in isolated skeletal muscle resistance arteries and in distal arterioles of the in situ cremaster muscle. Myogenic responses to increases in transmural pressure were also assessed in skeletal muscle resistance arteries of animals on high- or low-salt diets. Chronic (but not short-term) HS diet selectively potentiated angiotensin II-induced constriction of skeletal muscle resistance arteries relative to vessels from LS controls. Myogenic responses and norepinephrine-induced constriction of resistance arteries were unaffected by either chronic or short-term HS diet. Constriction of cremasteric arterioles in response to angiotensin II and norepinephrine was unaffected by chronic or short-term elevations in dietary salt intake. These data suggest that chronic elevations in dietary salt intake lead to a selective increase in the constriction of skeletal muscle resistance arteries to angiotensin II that may allow these vessels to continue to regulate their tone in response to this peptide, despite the suppression of angiotensin II that occurs with high-salt diet.

Angiotensin II↗
PubMed1994

Inhibition of neutral endopeptidase potentiates compound 48/80-induced constriction of guinea-pig tracheal smooth muscle.

Our previous studies have shown that the inhibition of neutral endopeptidase, an enzyme which degrades tachykinins, increases anaphylactic construction of guinea-pig tracheal smooth muscle. To investigate this observation further, we examined the effects of phosphoramidon, an inhibitor of a neutral endopeptidase, on constriction induced by the non-immunological mast cell degranulator-compound 48/80. Phosphoramidon produced significant leftward shift of the compound 48/80 concentration-response curve with corresponding decrease in the EC50 value from 51 (28-80) micrograms/ml to 42 (20-72) micrograms/ml. When added during the compound 48/80-induced constriction, phosphoramidon significantly increased the magnitude of this constriction by 69.7% after 30 min, and 78.9% after 45 min. Phosphoramidon was ineffective in tracheal rings from tachykinin-depleted guinea pigs. The incubation of tracheal rings with H1-histamine receptor antagonist (diphenhydramine HCl, 10 microM) and leukotriene receptor antagonist (ICI 198.615, 5 microM) significantly diminished the contractile response to compound 48/80 and prevented a phosphoramidon-dependent increase of this constriction. These results suggest that compound 48/80 induces the release of tachykinins by the stimulatory activity of histamine and leukotrienes. Anaphylactic release of tachykinins would therefore not depend directly on the antigen-antibody reaction.

Anaphylaxis↗
PubMed1990

Alpha 1-adrenergic coronary constriction during exercise and ischemia.

This paper reviews work primarily from our laboratories, examining an alpha 1-adrenergic receptor-mediated coronary constriction during exercise and myocardial ischemia in dogs. It was demonstrated that in the quiescent conscious dog, the coronary circulation is devoid of an alpha 1-coronary constriction. Furthermore, it was shown by the intracoronary injection of selective agonists that both alpha 1- and alpha 2-receptor subtypes are present in coronary vessels. However, during exercise or ischemia only the selective alpha 1-antagonist prazosin caused an increase in coronary inflow, indicating that only alpha 1-receptors were activated. During both conditions, the increase in flow caused by alpha 1-blockade was associated with an increased contractile function in subendocardium. In experiments on anesthetized dogs, it was shown that prazosin caused an equal increase in perfusion of subepicardial and subendocardial layers during stellate ganglion stimulation. However, contractile function was increased only in subendocardium. It was proposed that only in deeper muscle layers does an alpha 1-coronary constriction impose a flow-limitation on contractile function. Finally, recent results indicate that myocardial ischemia, produced either by partial coronary stenosis or by maintenance of coronary inflow at the resting level during exercise, may initiate a vicious cycle with a further increase in alpha 1-adrenergic coronary constriction. Abolition of this positive feedback mechanism may partially explain the anti-infarction effects of chronic ventricular sympathectomy, as previously observed in our laboratories.

Animals↗
PubMed1975

The constriction of the trapping rings in Dactylaria brochopaga.

The mechanism of ring constriction of a nematophagous fungus has been studied in vitro. The process of ring constriction in vivo normally requires less than one second. However, precise observations of the mechanism are difficult due to this rapidity, as well as the obstruction of the ring by the nematode. A method of initiating ring constriction without the use of an inert mechanical stimulus is described. With this method it is also possible to retard the constriction of the rings so that accurate observations of the entire process can be made. An explanation of the possible physiological mechanism is also presented.

Animals↗
PubMedDate not supplied

Relationship between epicardial and intramyocardial ST-segment voltage and myocardial blood flow during graded coronary constriction in the dog.

This study was undertaken to examine the relationship between electrographic ST-elevation and regional myocardial blood flow during graded coronary constriction. Electrograms from the epicardial surface, outer and inner layers of the myocardium were recorded. Regional blood flow to the outer and inner layers of the myocardium was measured by means of a heat-clearance method. With the application of a coronary constriction, myocardial blood flow to the inner layer began to decrease with a 75% coronary constriction, while flow to the outer layer was maintained at near normal up to least an 80% coronary constriction. Non-linear squares curve of between ST-elevation and the decrease in myocardial flow resulted in y = 18.80 exp-0.06x - 0.02 in the outer layer and y = 9.22 exp-0.02x - 1.54 in the inner layer. Also the non-linear squares curve of between epicardial ST-elevation and the decrease in myocardial flow resulted in y = 50.91 exp-0.11 x + 0.04 in the inner layer and y = 10.29 exp-0.07 x + 0.03 in the outer layer. The standard deviations of the coefficients of the latter two equations were higher than those of the former two equations. The higher values indicated larger variations of the parameter coefficients and data points. These results clearly demonstrated that a regional intramyocardial electrogram more closely reflects local ischemia than does an epicardial electrogram.

Animals↗