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PubMed2003

Cardiac angiosarcoma: an unusual presentation simulating mitral stenosis and constrictive-effusive pericarditis.

This case report details a patient with a cardiac angiosarcoma who had an unusual presentation with hemodynamics consistent with mitral stenosis and constrictive-effusive pericarditis. It illustrates how transesophageal echocardiography adds to the information obtained from transthoracic imaging and hemodynamics in this unusual presentation of a cardiac tumor.

Echocardiography, Transesophageal↗

PubMed2000

Reversal of the pattern of respiratory variation of Doppler inflow velocities in constrictive pericarditis during mechanical ventilation.

BACKGROUND: Spontaneous inspiration causes a characteristic decrease of the mitral valve (MV) and pulmonary venous (PV) flow velocities obtained by Doppler echocardiography in patients with constrictive pericarditis (CP). This has been explained by the decrement it causes in the intrathoracic pressure. Positive pressure ventilation (PPV) causes an increment of intrathoracic pressure with mechanical inspiration. Therefore the pattern of respiratory variation produced during PPV may differ from that seen during spontaneous breathing. OBJECTIVE: Our goal was to describe the effect of PPV on the pattern and magnitude of respiratory variation of MV and PV flow velocities in CP. METHODS: We performed intraoperative pulsed Doppler transesophageal echocardiography on 15 patients (13 men, mean age 52+/-15 years) with CP after general anesthesia and before sternotomy and pericardial stripping. The peak velocity and time-velocity integral (TVI) of the mitral inflow E and A waves and the PV systolic and diastolic waves were measured at onset of inspiration and expiration for 3 to 6 respiratory cycles. Respiratory phase was monitored with a heat-sensitive nasal thermistor. The percent change in Doppler flow velocities from mechanical inspiration (INS) to mechanical expiration (EXP) was calculated with the formula %change = INS - EXP / INS x 100. RESULTS: The peak velocity of the mitral inflow E wave was significantly higher during mechanical inspiration than expiration (57 +/-14.5 versus 47+/-13.9 cm/s, P<.001). This represented a percent change of 18%+/-7.9% from expiration to inspiration. The mean TVI of the mitral inflow E was also higher during mechanical inspiration than expiration (P = .02). The peak velocity of the PV D wave was higher during mechanical inspiration than expiration (39+/-17.8 versus 28+/-14.7 cm/s, P<.001). This represented a mean percent change of 28%+/-13.8%. The mean value of the TVI for the PV D wave was also significantly greater during mechanical inspiration than expiration (P <.05). CONCLUSIONS: Positive pressure ventilation reverses the pattern of respiratory variation of the MV and PV flow velocities in CP. The percent change in the peak velocities of the MV and PV flows produced by PPV is the same range reported in CP during spontaneous breathing.

Adult↗

PubMed2002

Diagnostic value of mitral annular velocity for constrictive pericarditis in the absence of respiratory variation in mitral inflow velocity.

Respiratory variation of 25% or more in transmitral early diastolic filling (E) velocity is a well-recognized diagnostic feature of constrictive pericarditis (CP) that is useful for distinguishing it from restrictive cardiomyopathy. However, a subset of patients with CP do not exhibit the typical respiratory change. Recent data showed that mitral annular (E') velocity measured by Doppler tissue echocardiography (DTE) is markedly reduced in patients with restrictive cardiomyopathy whereas E' velocity is well-preserved in CP. This study evaluated the role of DTE for the diagnosis of CP when there is no characteristic respiratory variation of E velocity. From September 1999 to March 2001, 19 patients (17 men, 2 women; mean age, 57 +/- 13 years) with surgically confirmed CP underwent comprehensive echocardiography preoperatively, including pulsed wave and DTE examination with simultaneous recording of respiration. Nine (47%) of the 19 patients had less than 25% respiratory variation in E velocity. There was no significant difference in mitral inflow peak velocity, deceleration time, early-to-late ventricular filling ratio, and E' velocity between patients with and patients without respiratory variation of E velocity of 25% or more. Regardless of the presence or absence of a significant respiratory variation of E velocity, E' velocity was relatively normal (mean, 12 +/- 4 cm/s) in all patients with CP. In conclusion, E' velocity is well preserved in patients with isolated CP even when there is no characteristic respiratory variation of E velocity. Thus, when the respiratory variation in Doppler E velocity is blunted or absent during the evaluation of suspected CP in patients with restrictive mitral inflow velocity, preserved E' velocity shown by DTE should support the diagnosis of CP over a primary myocardial disease.

Adult↗

PubMed2006

Transverse aortic constriction leads to accelerated heart failure in mice lacking PPAR-gamma coactivator 1alpha.

Heart failure is accompanied by important defects in metabolism. The transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator 1alpha (PGC-1alpha) is a powerful regulator of mitochondrial biology and metabolism. PGC-1alpha and numerous genes regulated by PGC-1alpha are repressed in models of cardiac stress, such as that generated by transverse aortic constriction (TAC). This finding has suggested that PGC-1alpha repression may contribute to the maladaptive response of the heart to chronic hemodynamic loads. We show here that TAC in mice genetically engineered to lack PGC-1alpha leads to accelerated cardiac dysfunction, which is accompanied by signs of significant clinical heart failure. Treating cardiac cells in tissue culture with the catecholamine epinephrine leads to repression of PGC-1alpha and many of its target genes, recapitulating the findings in vivo in response to TAC. Importantly, introduction of ectopic PGC-1alpha can reverse the repression of most of these genes by epinephrine. Together, these data indicate that endogenous PGC-1alpha serves a cardioprotective function and suggest that repression of PGC-1alpha significantly contributes to the development of heart failure. Moreover, the data suggest that elevating PGC-1alpha activity may have therapeutic potential in the treatment of heart failure.

Animals↗

PubMed1982

Constrictive pericarditis: techniques for differential diagnosis.

Although the incidence of constrictive pericarditis is low, the increasing number of patients receiving chronic dialysis, aggressive radiotherapy, or cardiovascular surgery has caused an increase in the iatrogenic incidence. The most common symptoms are dyspnea, fatigue, weight gain, peripheral edema, and abdominal swelling and discomfort. They may be present for years before the diagnosis is made. Physical examination, x-ray studies, electrocardiography, echocardiography, cardiac catheterization, and angiography are all helpful in the differential diagnosis. Pericardiectomy, the only treatment, has a success rate of up to 90%. Untreated, the condition progresses to an incapacitating state.

Angiography↗

PubMed1994

Complications associated with the use of vacuum constriction devices for erectile dysfunction in the spinal cord injured population.

The vacuum constriction device has generally been regarded as a safe and effective alternative to pharmacologic intracorporal injections or surgical placement of a penile prosthesis for the treatment of erectile dysfunction. This paper serves to exemplify the potential complications of the device when used to treat erectile dysfunction in the spinal cord-injured (SCI) population. Two cases of subcutaneous penile hemorrhage in patients using anticoagulant therapy (one treated with subcutaneous heparin and one with coumadin) and one case of penile gangrene occurred in three different SCI males. Physicians managing erectile dysfunction in SCI patients should be aware of these potential serious morbidities. The management and means of prevention of these complications are presented.

Adult↗

PubMed1999

Multifractal analysis of wide dynamic range neuron discharge profiles in normal rats and in rats with sciatic nerve constriction.

Using normal rats and rats with a chronic constriction injury of the sciatic nerve (injured, model of Bennett-Xie) we investigated the possibility of classifying, by statistical tools, the temporal sequences of neuronal discharges during different noxious and non-noxious stimuli. An analysis was made of both the distribution of the inter-spike intervals and the temporal density of spike trains, the latter being studied within the framework of stochastic universal multifractals, to allow the identification of different random processes involved in the discharge distributions through the Lévy index alpha. The statistical analysis shows that the parametrization based on the Lévy index seems able to discriminate between different noxious stimuli (mechanical pinching and thermal), both in normal and injured animals. Furthermore, comparing normal and injured animals, although the spontaneous basal and non-noxious stimuli (brushing) evoked activities presented different frequencies, these seem to have the same multifractal structure, while the corresponding statistics of the inter-spike intervals are quite different. This information might be relevant to the understanding of a code of neuronal firing and to the modelling of temporal patterns in acute and chronic noxious signals.

Algorithms↗

PubMedDate not supplied

Green tea pain modulating effect in sciatic nerve chronic constriction injury rat model.

We investigated the effect of green tea (GT) in unilateral chronic constriction injury (CCI) to the rat scaitic nerve. Five groups (n = 6 rats/group) sham group: rats which underwent operation but with no ligation to the scaitic nerve, and received tap water for two weeks before and for five weeks after the surgery. Four experimental groups underwent CCI to the right sciatic nerve, divided randomly as follows: group E were given tap water throughout the study. Group B received GT before and after CCI. Group C was given GT following CCI. Group D received GT for two weeks prior to CCI. Groups which consumed GT showed significant improvement in the toe spread (P < 0.001) and foot positioning (P < 0.001) tests compared to the experimental control group. In addition, these groups showed a significant decrease in the behavioral mechanical hyperalgesia (P < 0.0001) and allodynia (P < 0.0002). Consumption of GT improves both reflexes and sensation which are often affected in the course of peripheral neuropathy.

Analgesia↗

PubMed1994

Alterations in angiotensin II receptor mediated signal transduction shortly after coronary artery constriction in the rat.

OBJECTIVE: The aim of the study was to determine the effect of coronary artery constriction on the density of angiotensin II receptors and on the effector responses coupled with these receptors on myocytes one week after surgical induction of coronary artery stenosis in rats. METHODS: After induction of coronary artery stenosis and following the estimation of global cardiac performance, myocytes were enzymatically dissociated and radioligand binding studies were performed. In addition, the isotonic contractile performance, cytosolic calcium transients, and angiotensin II stimulated inositol phosphate generation in myocytes were measured in the presence and absence of the angiotensin II receptor subtype antagonist losartan. RESULTS: After documenting left ventricular failure and right ventricular dysfunction, the expression and density of angiotensin II receptors in left ventricular myocytes were evaluated and found to be increased 3.1-fold and 4.1-fold, respectively. Corresponding increases in right ventricular myocytes were 3.6-fold and 4.5-fold. In contrast, the quantity of the regulatory protein Gq alpha was not altered in either ventricle. Angiotensin II did not increase the generation of total inositol phosphates in left and right ventricular myocytes at maximum stimulation. However, the threshold for the formation of inositol phosphates was lowered in left ventricular myocytes of coronary narrowed rats. Measurements of single cell mechanics indicated that angiotensin II stimulation markedly improved the depression in myocyte function biventricularly. This inotropic effect was coupled with the restoration of cytosolic calcium. CONCLUSIONS: The upregulation of angiotensin II receptors on myocytes in this model of global ischaemia may be a compensatory mechanism ameliorating myocyte contractility in an attempt to sustain ventricular pump function.

Angiotensin II↗

PubMed1994

Coronary artery constriction in rats affects the activation of alpha 1 adrenergic receptors in cardiac myocytes.

OBJECTIVE: To determine whether alpha 1 adrenergic receptor mediated myocyte contractility and growth are depressed acutely after non-occlusive coronary artery narrowing, the left coronary artery was constricted in rats and mechanical behaviour, cytosolic calcium, and regulation of alpha 1 adrenergic receptors were examined in myocytes seven days later. METHODS: Coronary artery stenosis was surgically induced in rats and following the estimation of global cardiac performance myocytes were enzymatically dissociated and radioligand binding studies were performed. In addition, the isotonic contractile performance, cytosolic calcium transients and noradrenaline stimulated inositol phosphate generation in myocytes were measured in the presence of WB 4101 or after chlorethylclonidine treatment. RESULTS: Estimations of cell mechanics in vitro established that peak shortening was decreased by 36% and 18% in left and right ventricular myocytes of coronary stenosed rats. Time to peak shortening was prolonged by 29% in left and 20% in right myocytes, whereas velocity of shortening was decreased by 27% in left myocytes. These alterations were associated with increases in cell length and width, indicative of myocyte hypertrophy. In addition, coronary stenosis was accompanied by reductions in the expression of alpha 1a and alpha 1b receptor subtypes in myocytes. alpha 1 Adrenergic receptor density and noradrenaline stimulated phosphoinositol turnover were decreased by 30% and 34% in left myocytes. alpha 1a Adrenergic receptor subtype mediated cytosolic calcium concentration and myocyte mechanical performance were also impaired in left myocytes only. The alpha 1a adrenergic receptor subtype antagonist WB 4101 abolished noradrenaline stimulated inositol phosphate generation in myocytes, whereas chlorethylclonidine at large doses only partially inhibited this response. CONCLUSIONS: In conclusion, coronary narrowing leads to defects in the regulation of alpha 1 adrenergic receptors on myocytes which are coupled with attenuation in the transmission of signals, possibly affecting myocyte cell function and ongoing reactive cellular hypertrophy.

Adrenergic alpha-Antagonists↗

PubMedDate not supplied

Role of echocardiography in detecting the anatomic and physiologic abnormalities of constrictive pericarditis.

Constrictive pericarditis (CP) is associated with thickening of the pericardium (P), rapid filling of the ventricles, and a steep rise of early diastolic pressure in the right and left ventricles. We investigated the frequency with which echocardiography detects the characteristic anatomic and physiologic abnormalities of CP. M-mode echocardiography was performed in 10 patients with CP. All patients had evidence of pericardial thickening. Eight patients had motion of the P parallel to the epicardium with an echo-free space between the two structures. Two patients had a small pericardial and left pleural effusion sandwiching the P which measured 8 mm, and 14 mm respectively. Premature pulmonic valve opening indicating a high right ventricular early diastolic pressure which exceeded the pulmonary artery diastolic pressure was present in all 5 patients in whom the pulmonic valve was recordable. A notch on the septum in early diastole was seen in 6 patients. Sharp posterior motion of the left ventricular posterior wall in early diastole followed by a flat segment was noted in 7 patients. Motion of the posterior wall of the aortic root (PWAo) in diastole has been shown to indicate left atrial volume changes or reflect left ventricular filling. An index of early diastolic left ventricular filling derived from the motion of the posterior wall of the aortic root, indicated abnormally rapid early diastolic filling in all 8 patients in whom this was measured. We conclude: 1) The anatomic and physiologic abnormalities in CP are commonly reflected on the echocardiogram, and 2) echocardiography should be useful in evaluation of patients suspected of having CP.

Adult↗

PubMed2001

alpha-1 and alpha-2 Adrenergic antagonists relieve thermal hyperalgesia in experimental mononeuropathy from chronic constriction injury.

Phentolamine, a nonspecific alpha 1- and alpha 2-adrenergic antagonist, relieves pain in patients with reflex sympathetic dystrophy. We sought to determine whether phentolamine, prazosin (alpha 1 antagonist), or SKF86466 (alpha 2 antagonist) relieve thermal hyperalgesia in rats with neuropathic pain. Four days after producing a chronic constriction injury (CCI), thermal hyperalgesia was tested by measuring paw withdrawal latency (PWL). After injection of phentolamine, prazosin, or SKF86466 each at doses of 1, 2, or 5 mg/kg, PWL tests were measured at 5 min and repeated at 15-min intervals for 1 h. Phentolamine, prazosin, and SKF86466 1, 2, and 5 mg/kg provided statistically significant analgesia in rats with CCI for at least 65 min. PWL did not return to baseline levels after 1 or 2 mg/kg of prazosin or SKF86466 but did so after 35 min after phentolamine 2 mg/kg. After 5 mg/kg, PWL returned to preoperative values between 5 and 50 min for phentolamine, at 35 and 65 min for prazosin, and at 50 min for SKF86466. We conclude that both alpha1 and alpha2 peripheral receptors of the sympathetic nervous system are involved in the thermal hyperalgesia caused by CCI and that thermal hyperalgesia can be reversed by both alpha1 and alpha2 antagonists in a dose-dependent manner.

Adrenergic alpha-1 Receptor Antagonists↗

PubMed2001

Digital constriction bands in pseudoainhum: morphological radiographic, and histological analysis.

Pseudoainhum is a rare condition of unknown etiology that produces digital constricting rings, most commonly on the small fingers. A thorough discussion of pseudoainhum in the plastic surgical literature is apparently lacking at this time. The authors describe the gross morphology, radiographic and laboratory features, and surgical pathology of the disease, and provide well-defined guidelines for its treatment.

Adult↗

PubMed1999

Ectopic purinergic sensitivity develops at sites of chronic nerve constriction injury in rat.

The possibility that ectopic purinergic sensitivity develops following peripheral nerve injury was investigated in chronic constriction injury (CCI). Spontaneous firing of A-fibers originated from the injury site or from sensory endings of afferents in the contralateral sciatic nerve. ATP injected intravenously excited most of the injured fibers whereas none of the contralateral afferents responded to ATP. The ATP-induced effect was blocked by the P2 receptor antagonist reactive blue 2, but not the P1 receptor antagonist aminophylline. Neither the alpha-adrenoreceptor antagonist phentolamine nor the cyclooxygenase inhibitor indomethacin attenuated the ATP-evoked effect. We conclude that a novel ectopic purinergic sensitivity mediated by P2 receptors develops at sites of the CCI of nerves in the rat, which may contribute to neuropathic pain.

Adenosine Triphosphate↗

PubMed1990

Constrictive pericarditis causing a positive TI-201 SPECT stress test for myocardial ischemia.

A case of constritive pericarditis was demonstrated by a positive thallium SPECT stress test for myocardial ischemia. After pericardiectomy, the repeat thallium stress test was normal. The disappearance of the criteria for a positive test suggests that constrictive pericarditis can cause myocardial ischemia, which can be demonstrated by thallium SPECT stress testing.

Coronary Disease↗

PubMed1990

Chylous ascites should suggest constrictive pericarditis even in a patient with cirrhosis.

Chylous ascites, a milky, high triglyceride fluid is usually found in patients with lymphatic obstruction from malignancy. We describe a patient with cirrhosis who developed constrictive pericarditis and chylous ascites. Long-standing portal hypertension compounded by elevated central venous pressure provided several pathophysiologic contributions to the formation of the chylous ascites. Chylous ascites even in a cirrhotic requires prompt assessment for conditions leading to elevated central venous pressure.

Chylous Ascites↗

PubMed1991

Constrictive pericarditis masquerading as Budd-Chiari syndrome.

Budd-Chiari syndrome (BCS) and constrictive pericarditis (CP) share many common clinical features. Over the last year we encountered three patients in whom CP clinically mimicked BCS. Two of the three did not even have raised jugular venous pressure. One patient with severe jaundice and hepatic coma ultimately died. Liver biopsy features were not discriminating. The final diagnosis of CP was established by echocardiography, chest computed tomography (CT), or cardiac catheterization. We conclude that in all patients with apparent BCS and atypical features, a noninvasive test like echocardiography or chest CT should be done to rule out treatable illness like CP before embarking on such invasive procedures as liver biopsy for diagnosis.

Adolescent↗

PubMed1980

Severe adhesive constrictive pericarditis after coronary artery bypass.

The patient described presented with typical clinical symptoms of constrictive pericarditis nine months after triple saphenous vein bypass. No cause could be found. Cardiac catheterization confirmed the clinical diagnosis. At pericardiectomy a severely thickened pericardium which was intimately adherent to the heart and great vessels made its resection technically impossible.

Coronary Artery Bypass↗