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PubMed1984

Reflex constriction of significant coronary stenosis as a mechanism contributing to ischemic left ventricular dysfunction during isometric exercise.

To study the mechanisms of myocardial ischemia during isometric exercise, handgrip was sustained, for 4.5 min at 25% of maximum by 11 patients with at least one significant coronary stenosis each, during cardiac catheterization. After recovery, the handgrip that was repeated with simultaneous infusion of nitroglycerin (50 micrograms over 4 min) directly into the diseased vessel. The cardiovascular response was assessed by hemodynamic and by computer-assisted measurements of stenosis. During the first handgrip test pulmonary capillary wedge pressure rose 56% (15 to 23 mm Hg; p less than .001), the heart rate-systolic pressure product rose 33% (p less than .01), and the diseased epicardial arteries constricted. Luminal area in the stenotic segment was reduced by 35% (p less than .01), resulting in a 243% increase in estimated stenotic flow resistance (30 to 103 mm Hg/ml/sec; p less than .001). During handgrip with intracoronary nitroglycerin, the pressure-rate product again increased 33%, but relative to resting control, capillary wedge pressure fell 4 mm Hg in association with a 32% increase in luminal area of the stenosis and a 28% reduction in flow resistance (all significantly different from the response to handgrip alone: p less than .001, .01, and .005, respectively). Thus, coronary vasoconstriction, not increased pressure-rate product, is the dominant mechanism for ischemic left ventricular dysfunction during isometric exercise in patients with significant coronary stenoses.

Adult↗
PubMed1987

Leukotriene C4- and D4-induced diffuse peripheral constriction of swine coronary artery accompanied by ST elevation on the electrocardiogram: angiographic analysis.

Effects of leukotriene (LT) C4 and LTD4 on coronary artery spasm in atherosclerotic miniature pigs were examined angiographically. Endothelial balloon denudation of the left circumflex coronary artery was performed in 15 Göttingen miniature pigs; 11 were fed a 2% cholesterol diet and four were fed a regular diet for 3 months. Three months after this denudation, the area of the coronary artery was reduced by 94 +/- 2% and 43 +/- 5% (p less than .01) in the denuded and nondenuded areas by the intracoronary administration of 10 micrograms/kg histamine after pretreatment with 60 mg/kg iv cimetidine. The effects of LTC4 and LTD4 on coronary diameter and the preventive effects of FPL-55712, a LTC4 and LTD4-receptor blocker, or diphenhydramine, a histamine H1-receptor blocker, on histamine-induced coronary spasm were then examined angiographically. Administration of LTC4 or LTD4 in doses of 1 and 10 micrograms into the left coronary artery, or selectively into the left circumflex and left anterior descending coronary arteries in a dose of 5 micrograms, led to the elevations in the ST segment on the electrocardiogram and there was delayed filling of the contrast medium in the peripheral coronary artery. However, these LTs provoked no augmented constrictions at any site on the epicardial coronary arteries (n = 15). Diphenhydramine, 1 mg/kg (n = 6), abolished the histamine-induced coronary spasm FPL-55712, 0.1 mg/kg, with which the LT-induced myocardial ischemia was abolished, did not prevent the histamine-induced coronary artery spasm.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗
PubMed1996

Value of dynamic respiratory changes in left and right ventricular pressures for the diagnosis of constrictive pericarditis.

BACKGROUND: Conventional cardiac catheterization criteria for the diagnosis of constrictive pericarditis (CP) rely on equalization of intracardiac pressures and have many recognized limitations. Recently, Doppler echocardiographic methods have been used to examine dynamic respiratory changes of increased ventricular interdependence and dissociation of intrathoracic and intracardiac pressures for the diagnosis of CP. These pathophysiological features may be best delineated by cardiac catheterization. Therefore, we studied the accuracy of these dynamic respiratory changes in left ventricular and right ventricular pressure for the diagnosis of CP at cardiac catheterization. METHODS AND RESULTS: High-fidelity manometric catheters and respirometry were used to study 36 patients: 15 patients with surgically proven CP (group 1) and 21 patients with other causes of heart failure (group 2). Conventional cardiac catheterization variables used to establish the diagnosis of CP lacked sensitivity and specificity and failed to distinguish between these groups. However, the finding of discordance between right ventricular and left ventricular pressures during inspiration, a sign of increased ventricular interdependence, accurately distinguished patients in group 1 from those in group 2 (P < .05). CONCLUSIONS: Examination of dynamic respiratory changes indicating increased ventricular interdependence may be helpful in the diagnosis of CP in the cardiac catheterization laboratory.

Adult↗
PubMed1989

Change of residual strains in arteries due to hypertrophy caused by aortic constriction.

The stress and strain that remain in an organ when the external load is removed are called residual stress and strain. They can be revealed by cutting up the organ in such a way as to reveal the zero-stress configuration. The function of the organ depends on the residual strain. For a blood vessel, the zero-stress configuration is very different from that of the no-load condition, and it changes over time when the physical stress acting on the vessel is changed. Data on rat aorta are presented. Physical changes were obtained by constricting the aorta at the celiac trunk level with a band of metal. Banding causes an increase of blood pressure and hypertrophy of the vessel in the upper body and a transient decrease of blood pressure in the lower body. If the aorta is cut transversely into rings and each ring is cut radially, it will open up into a noncircular arc, which may be characterized by its opening angle. It is shown that the opening angle varies systematically along the aorta and that it changes significantly together with changes of blood pressure and hypertrophy. In the ascending aorta, the opening angle increased from 171 degrees and to 214 degrees in 4 days after banding, then decreased gradually to an asymptotic value of 126 degrees in 40 days. At other sections, the swing of opening angle is smaller. The implications are discussed.

Animals↗
PubMed2001

Annulus paradoxus: transmitral flow velocity to mitral annular velocity ratio is inversely proportional to pulmonary capillary wedge pressure in patients with constrictive pericarditis.

BACKGROUND: The early diastolic velocity of the mitral annulus (E') is reduced in patients with diastolic dysfunction and increased filling pressures. Because transmitral inflow early velocity (E) increases progressively with higher filling pressures, E/E' has been shown to have a strong positive relationship with pulmonary capillary wedge pressure (PCWP) and left ventricular end-diastolic pressure. However, previous studies have primarily involved patients without a pericardial abnormality. In constrictive pericarditis (CP), E' is not reduced, despite increased filling pressures. This study evaluated the relationship between E/E' and PCWP in patients with CP. METHODS AND RESULTS: We studied 10 patients (8 men; mean age, 64+/-7 years) with surgically confirmed CP. Doppler echocardiography was performed to measure early and late diastolic transmitral flow velocities. Tissue Doppler echocardiography was performed to measure E'. PCWP was measured with right heart catheterization. All patients were in sinus rhythm. Mean E and E' were 91+/-15 cm/s and 11+/-4 cm/s, respectively. Mean PCWP was 25+/-6 mm Hg. E' was positively correlated with PCWP (r=0.69, P=0.027). There was a significant inverse correlation between E/E' and PCWP (r=-0.74, P=0.014). Despite high left ventricular filling pressures, E/E' (mean, 9+/-4) was <15 in all but 1 patient. CONCLUSIONS: Paradoxical to the positive correlation between E/E' and PCWP in patients with myocardial disease, an inverse relationship was found in patients with CP.

Aged↗
PubMed1990

Oxygen radicals produce airway constriction and hyperresponsiveness in anesthetized cats.

Using 30 anesthetized cats, we examined whether oxygen radicals produce airway constriction or hyperresponsiveness. In one group, we administered aerosolized xanthine (0.1%) for 3 min followed by aerosolized xanthine oxidase (XO) (1 U/ml) for 5 min in order to generate oxygen radicals enzymatically in the airways. Pulmonary resistance (RL) instantaneously increased from 14.8 +/- 0.9 to 30.8 +/- 1.4 cm H2O/L/s (p less than 0.01). The increase in RL was significantly depressed by prior administration of polyethylene glycol-superoxide dismutase (PEG-SOD) or polyethylene glycolcatalase (PEG-CAT). In a second group, in order to examine changes in airway responsiveness, we studied acetylcholine (ACh) challenge before and 30, 60, and 120 min after inhalations of xanthine and XO. After xanthine-XO, the airways were hyperresponsive to ACh at 30 and at 60 min (p less than 0.05) but not at 120 min. The geometric means of ACh provocative concentrations that caused an increase in RL of 10 cm H2O/L/s above the baseline value before and 30, 60, and 120 min after xanthine-XO were 0.25, 0.045, 0.073, and 0.15%, respectively. The increase in responsiveness to ACh was significantly correlated with the increase in RL after xanthine-XO inhalation (r = 0.88, p less than 0.05). These data support the concept that oxygen radicals generated by xanthine-XO inhalation may induce bronchoconstriction and airway hyperresponsiveness.

Acetylcholine↗
PubMed1991

Impaired inotropic responses to adrenergic stimulation following aortic constriction: role of oxidation product of catecholamines.

In order to support the hypothesis that oxygen free radicals derived from persistent sympathetic drive play an important role in the modulation of receptor-mediated effect in cardiac hypertrophy, rat hearts subjected to aortic banding-induced pressure overload were assessed on postoperative days 3, 14, and 28. Sham-operated rats without aortic banding were used as a control group. Cardiac alpha-adrenoceptors were increased at day 3 whereas beta-adrenoceptors were increased at postoperative days 14 and 28; these results were associated with increased amount of circulating norepinephrine and adrenolutin, one of the oxidation products of catecholamines. The hearts of these animals were also perfused by Langendorff technique in the presence and absence of adrenergic agonists. Banded animals had a diminished inotropic response to alpha agonists in addition to their reduced inotropic responsiveness to beta-adrenergic stimuli. These changes were however, reversible in animals pretreated with alpha-tocopherol, a powerful antioxidant. Furthermore, the circulating level of adrenolutin was normalized by such treatment. These results indicate that an oxidation product of catecholamines may be responsible for impaired inotropic responses to adrenergic stimulation following aortic constriction.

Animals↗
PubMed2003

Acquired constriction ring syndrome.

A case of "acquired constriction ring" or "toe-tourniquet" syndrome is presented to increase awareness of the condition in the orthopaedic community. If treated promptly, this condition has a very good prognosis and, if the diagnosis is missed, may lead to amputation. We also discuss the potential causes and presentation of this condition, along with the need for urgent surgical exploration if there are doubts over tissue viability.

Constriction↗
PubMed2026

Disseminated meningococcal infection presenting with constrictive pericarditis and bilateral septic arthritis without meningitis: A case report.

Invasive meningococcal disease is a life-threatening infection that classically presents as meningitis or meningococcemia. Extra-meningeal manifestations, including pericarditis and septic arthritis, are uncommon and may complicate diagnosis, particularly in the absence of meningeal involvement. A previously healthy vaccinated man in his 50s presented with acute bilateral knee pain and swelling following a short history of fever, productive cough, fatigue, and dyspnea. Blood cultures grew Neisseria meningitidis serogroup W, whereas cerebrospinal fluid, synovial fluid, and pericardial fluid cultures remained negative. Cardiac magnetic resonance imaging demonstrated constrictive pericarditis with circumferential pericardial enhancement and pericardial effusion. The patient was successfully treated with intravenous ceftriaxone, colchicine, ibuprofen, pericardiocentesis, and bilateral knee washout, followed by oral ciprofloxacin. This case adds to the limited literature describing concurrent cardiac and musculoskeletal manifestations of invasive meningococcal disease without meningitis and shows the importance of early recognition, comprehensive investigation and multidisciplinary management of these uncommon presentations.

Neisseria meningitidis↗
PubMed1991

A case of effusive constrictive pericarditis caused by Streptococcus milleri.

A 55-year-old male presented with hypotension and marked elevation of jugular venous pressure suggesting impaired ventricular filling. Echocardiography demonstrated a moderate amount of pericardial effusion and dense and shaggy fibrinous strands attached to the pericardia. Pericardiocentesis was performed under the diagnosis of cardiac tamponade, but normal ventricular filling could not be restored even after pericardiocentesis. Hemodynamic evaluation after pericardiocentesis revealed persisting low cardiac output, elevation and equilibration of right atrial, right ventricular end-diastolic and pulmonary capillary wedge pressures, and deep y descent. Later, surgical removal of the thickened pericardium was required. This case appeared to be typical effusive-constrictive pericarditis. Regarding etiology, a rare organism, Streptococcus milleri, proved to be responsible, while the case history and clinical situation were suggestive of a tuberculous or tumorous origin.

Hemodynamics↗
PubMed1996

Pericardiectomy and coronary artery bypass grafting for constrictive pericarditis after heart surgery.

A 63-year-old male was operated on for chronic heart failure due to myocardial ischemia and constrictive pericarditis after heart surgery. He was in New York Heart Association (NYHA) class III under a large dose of diuretics. He underwent a pericardiectomy and coronary bypass surgery without cardiopulmonary bypass. His cardiac function improved with a patent graft. He is now, 1 year after surgery, in NYHA class I under a tapering dose of diuretics.

Cardiac Output, Low↗
PubMed2000

Primary pericardial mesothelioma presenting as constrictive pericarditis: a case report.

Primary malignant pericardial mesothelioma is a rare tumor and the case reported here presented as constrictive pericarditis. The patient's symptoms progressed day by day despite treatment with digitalis, diuretics and catecholamines. Although a computed tomographic scan of the chest, echocardiography and pericardiocentesis were performed, a preoperative definitive diagnosis could not be obtained. Emergency pericardiectomy and partial resection of the tumor were carried out with the aid of a percutaneous cardiopulmonary supporting system, but the patient died of cardiac failure on postoperative day 3. The tumor appeared to be the biphasic type of diffuse malignant mesothelioma. The prognosis for pericardial mesothelioma is extremely poor due to its late presentation and difficulty in completely removing it surgically and, unfortunately, there still is not a radical therapy for this tumor.

Diagnosis, Differential↗
PubMed2001

Clinical characteristics of patients with constrictive pericarditis after coronary bypass surgery.

Constrictive pericarditis (CP) is an unusual sequela of cardiac surgery, so the present study evaluated the clinical characteristics of patients with CP after coronary artery bypass grafting (CABG). Four hundred and sixty-three patients who underwent isolated CABG between January 1989 and March 1999 were examined retrospectively. The first choice of treatment for postoperative pericardial effusion was non-steroid anti-inflammatory agents, and an increased dose of diuretics. The second treatment choice was corticosteroids or pericardial drainage. When CP was suspected during the follow-up period (mean, 54+/-31 months), cardiac catheterization was carried out to establish the diagnosis. Of the 463 patients undergoing CABG, there were 11 (2.4%) who developed CP after surgery. The median time to the onset of symptoms after CABG was 4 weeks (range, 3-96 weeks). On univariate and multivariate analysis, normal left ventricular ejection fraction, warfarin administration, and early postoperative pericardial effusion were significantly associated with a greater potential of postoperative CP. The effusion was bloody in all cases of pericardial drainage despite warfarin therapy. Not draining the postoperative effusive pericardial effusion was a risk factor for the development of CP. Pericardial drainage for patients with significant effusion after CABG is important for the prevention of subsequent CP, especially in those patients being treated with warfarin or with normal left ventricular function.

Aged↗
PubMed2002

Pericardial constriction: diagnosis and management.

The diagnosis of pericardial constriction is challenging and elusive. It is a postinflammatory condition that occurs when a thickened, fibrotic, scarred and sometimes calcified pericardium firmly encases the cardiac chambers and restricts filling of the heart, causing venous overload and diminished cardiac output. This review includes the diagnosis and management of this condition.

Biopsy↗
PubMed1992

Functional upper airway obstruction. Psychogenic pharyngeal constriction.

A 15-year-old boy, known to have asthma, developed acute inspiratory airway obstruction with marked stridor. Spirometry indicated extrathoracic airway obstruction and a bronchofiberoptic examination disclosed narrowing in the hypopharynx. After administration of sedatives, the stridor suddenly disappeared. Psychotherapy decreased the frequency of subsequent stridor attacks. It is suggested that psychogenic pharyngeal constriction may have caused the upper airway obstruction with respiratory distress.

Adolescent↗
PubMed1977

False-positive echocardiographic diagnosis of pericardial effusion. Result of tumor encasement of the heart simulating constrictive pericarditis.

A 46-year-old man had advanced squamous cell carcinoma of the lung and apparent constrictive pericarditis. Echocardiographic studies twice demonstrated apparent pericardial effusions, but pericardiocenteses were unsuccessful. Tumor encasement of the heart was diagnosed clinically and at necropsy. This entity is yet another cause of a false-positive echocardiographic diagnosis of pericardial effusion.

Autopsy↗
PubMed1989

Constrictive pericarditis with electrocardiographic evidence of right ventricular hypertrophy.

We report the findings in a patient with constrictive pericarditis who had ECGs resembling right ventricular hypertrophy without right ventricular pressure overload, and we provide a possible explanation for the cause of this abnormality. Right ventriculography demonstrated a dilated and hyperkinetic outflow tract and compressed free wall with calcified pericardium. The derangement of the configuration of the right ventricle was considered to be the genesis of this electrocardiographic abnormality.

Adolescent↗