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At least 1,027 records · Page 57Linked to original sources
PubMed1996

Dual chamber pacing with a single lead system: initial clinical results.

A new mode of biphasic pacing was used in 26 patients to assess the feasibility of atrial pacing by means of the floating atrial ring electrodes of a single lead VDD permanent pacing system. During implantation, atrial pacing was possible in 25 patients with a 1-ms total pulse duration, a mean atrial threshold of 1.70 +/- 0.60 V (range, 0.6-3.0), and a mean diaphragmatic threshold of 6.7 +/- 2.5 V (range, 2.5-10.0). At 3 months, the atrial threshold had increased beyond 4.8 V in three patients. In the 22 other patients, the mean atrial threshold was 2.2 +/- 0.5 V (range, 1.50-3.50) in the supine position and 2.5 +/- 0.8 V (range, 1.5-4.8) in the sitting position. Stable atrial capture without diaphragmatic stimulation was achieved in 76% of patients.

Adult↗
PubMedDate not supplied

[Hernia hiatal. Detection of gastroesophageal reflux with the telemetric Heidelberg capsule].

120 patients with upper gastrointestinal symptoms were studied and submitted to gastric secretory tests, upper gastrointestinal X-rays and endoscopy. Gastroesophageal reflux was assessed by means of a Heidelberg telemetric capsule. 60 patients had hiatal hernia. Gastroesophageal reflux was present in 63.33%. 76% of the patients with hiatal hernia had gastroesophageal reflux, especially on those with small hernias and on the 5th and 6th decade of life. Gastric hiperacidity facilitates the incidence and presence of reflux. X-rays and endoscopy allowed us to diagnose diseases at the gastroesophageal junction. The correlation between these 2 methods and the presence or not of reflux, allowed differentiation between patients with organic diseases and patients with "functional" symptoms.

Age Factors↗
PubMed2006

[Adeno-associated viral gene transfer of SERCA2a improves heart function in chronic congestive heart failure rats].

OBJECTIVE: To study the therapy effect of adeno-associated viral gene transfer of sarcoplasmic reticulum Ca(2+)-ATPase 2a (SERCA2a) on chronic congestive heart failure (HF) in 30 days, and the possible mechanism of the therapy effect. METHODS: The rats were divided into four groups: control group, HF group, Group HF + EGFP, and Group HF + SERCA2a. HF rats were obtained by creating descending aortic constriction. 0.9% sodium chloride solution, recombinant adeno-associated virus carrying enhanced green fluorescent protein gene (rAAV2.eGFP) and recombinant adeno-associated virus carrying SERCA2a gene (rAAV2.SERCA2a), were respectively delivered to pericardium of HF rats in different groups by intrapericardial injection with a trans-diaphragmatic approach. 30 days after gene transfer, hemodynamic parameters, SERCA2a protein expression and SERCA2a activity were analyzed. The proteome difference from rat hearts between Groups HF + SERCA2a and HF was detected by expression proteomics. Electrophoretic separation and quantitation of cardiac myosin heavy chain isoforms of hearts in different groups were performed at 30 days. RESULTS: At 30 days, left ventricular function improved significantly in HF rats infected with rAAV2.SERCA2a (LVSP 146.52 +/- 13.86 vs 97.91 +/- 12.13, LVEDP 7.88 +/- 2.88 vs 21.15 +/- 3.57, LV +dp/dt 11 206.16 +/- 1730.11 vs 5948.93 +/- 1283.43, LV -dp/dt -8249.54 +/- 1076.09 vs -4497.50 +/- 652.12; P < 0.05). The recovered cardiac function in Group HF + SERCA2a rats was comparable to control rats, and had lower LV-weight/Body-weight ratio (2.46 +/- 0.17 vs 2.71 +/- 0.24, P < 0.05). Overexpression of SERCA2a increased both the protein content (0.39 +/- 0.11 vs 1.11 +/- 0.18, P < 0.05) and activity (228.62 +/- 25.11 vs 82.55 +/- 14.13, P < 0.05) up to nonfailing levels. Expressions of some energy metabolic enzymes in hearts of Group HF + SERCA2a were much higher than those of HF group. They included creatine kinase-muscle, enolase beta, fructose-bisphosphate aldolase, mitochondrial H(+)-ATP synthase alpha subunit, electron transfer flavoprotein alpha-subunit, H(+)-transporting ATP synthase and heart fatty acid binding protein. Downregulation of alpha-MHC and upregulation of beta-MHC in failing hearts were observed. Gene transfer of SERCA2a could increase the expression of alpha-MHC [(74.48 +/- 3.74)% vs (53.57 +/- 2.30)%, P < 0.05], and decrease the expression of beta-MHC [(25.52 +/- 3.74)% vs (46.43 +/- 2.30)%, P < 0.05] in HF rats. The expression profiles of alpha-MHC and beta-MHC and the ratio of alpha-MHC/beta-MHC were similar to those in controls. CONCLUSIONS: Adeno-associated viral gene transfer of SERCA2a can enhance SERCA2a functions, maintain calcium homeostasis, improve cardiac energy metabolism, and normalize the expression of cardiac myosin heavy chain isoforms in HF rats. As a result, the ventricular systolic and diastolic functions can be improved significantly, and the hypertrophy of the heart may be reduced in clinic. Adeno-associated viral gene transfer of SERCA2a demonstrated good therapy effects on HF rats.

Adenoviridae↗
PubMed2004

Spontaneous bilateral diaphragmatic paralysis: a rare cause of respiratory failure.

Bilateral diaphragmatic paralysis (BDP) can occur in the course of motor neuron disease, myopathy, or from mechanical damage or the use of "ice slush" during cardiac surgery. BDP has been observed during and after infections, associated with systemic lupus erythematosus and mediastinal tumors, or may have idiopathic etiology. It is a serious and life-threatening condition. A 62-yr-old man presented with slowly progressive dyspnoea that worsened in the supine position and on bending forward. Chest X-rays, fluoroscopy, lung-function parameters and blood-gas analysis revealed respiratory failure. BDP was confirmed from a phrenic nerve stimulation test and measurement of transdiaphragmatic pressure (Pdi). Since there was no evidence of an obvious etiology, BDP was considered idiopathic. Other muscles were not involved. The pathological basis was probably focal demyelination in segments of the phrenic nerve. Because of increasing diaphragmatic muscle fatigue, the patient was treated with a nasal mask providing bi-level positive airway pressure (BiPAP) ventilation during the night. Clinical suspicion of BDP should always be raised in patients suffering slowly progressive dyspnoea without any obvious cardiac, metabolic or traumatic predisposing factors, and orthopnoea and dyspnoea on bending forward. Electromyographic tests and measurement of Pdi can reveal the correct diagnosis.

Dyspnea↗
PubMed2006

Ablation of diaphragmatic annular ureteral valve with holmium laser.

We report laser ablation of a diaphragmatic ureteral valve. Annular diaphragmatic ureteral valves are a rare cause of ureteral obstruction. We believe this to be the first reported case of laser ablation of a ureteral valve. Follow-up at 2 years revealed preserved renal function and unobstructed drainage.

Humans↗
PubMed1998

An early onset muscular dystrophy with diaphragmatic involvement, early respiratory failure and secondary alpha2 laminin deficiency unlinked to the LAMA2 locus on 6q22.

We present four subjects from one family and one subject (with an affected sibling who had died) from a second, unrelated family, with early onset, Duchenne-like, muscular dystrophy who presented with proximal girdle weakness, calf and generalized muscle hypertrophy, selective wasting of the sternomastoid muscles, rigidity of the spine and contractures of the tendo Achilles. Intellect was normal. Serum creatine kinase was grossly elevated and the muscle biopsies showed a dystrophic picture. All five subjects have developed early respiratory failure due to severe diaphragmatic involvement; two have already died aged 4 and 7 years of age and the remaining three are dependent on night time ventilation. There has been very little deterioration over time in the skeletal muscle function, and the survivors remain ambulant, the oldest being 11 years. Immunocytochemical studies of the muscle biopsy showed a normal pattern for dystrophin and the dystrophin-associated glycoproteins, but a reduction of the laminin alpha2 chain of merosin. Magnetic resonance imaging of the brain was normal. The disease did not link to the LAMA2 locus for laminin alpha2 on chromosome 6q, so that these families seem to represent a new form of autosomal recessive muscular dystrophy with a secondary merosin deficiency. The primary protein deficiency has not yet been identified.

Age Factors↗
PubMed1990

Diagnosis of congenital cystic adenomatoid malformation of the lung in newborn infants and children.

Seventeen patients were diagnosed as having congenital cystic adenomatoid malformation of the lung during 1970-88. One case was associated with congenital diaphragmatic hernia and the child died before operation. The other 16 children underwent successful surgery. The patients presented in one of three ways--with neonatal respiratory impairment (12 cases) requiring urgent diagnosis and treatment, with recurrent respiratory tract infections (3), and with pneumothorax (1). Diagnostic problems arose with the neonatal presentation. In four of the children laparotomy was performed for presumed diaphragmatic hernia; three of these children had right sided lesions. Congenital diaphragmatic hernia was excluded by contrast studies in a further two patients. Histological examination confirmed the diagnosis in all cases. The postoperative course was uneventful in all 16 patients. No long term impairment of pulmonary function was noted.

Child↗
PubMed1980

Mechanism of hemoglobin desaturation during rapid-eye-movement sleep in normal subjects and in patients with cystic fibrosis.

To assess the mechanism of the decrease in hemoglobin O2 saturation during rapid-eye-movement sleep, we studied 5 normal subjects 22 to 30 yr of age and 20 patients with cystic fibrosis 9 to 29 yr of age. The largest decrease in arterial O2 saturation, as monitored with an ear oximeter during sleep, occurred during rapid-eye-movement sleep, with a mean +/- SEM decrease of 2 +/- 0.31% in the normal subjects and 7.4 +/- 1.3% in the patients in both groups. Rapid-eye-movement sleep was associated with a significant loss of intercostal and diaphragmatic tonic muscle activity (p < 0.01), as monitored with surface electrodes, and a decrease in the baseline position of the rib cage and abdomen, as recorded by magnetometers (p < 0.01). This suggests a decrease in functional residual capacity, which was accompanied by a consistently lower arterial O2 saturation during rapid-eye-movement sleep. Short periods (< 20 s) of inhibition of phasic respiratory muscle activity during rapid-eye-movement sleep were followed by further decreases in arterial O2 saturation. We conclude that the desaturation during rapid-eye-movement sleep in all subjects was mainly due to a decrease in functional residual capacity, leading to airway closure in the dependent lung regions. The hemoglobin desaturation was further aggravated by transient periods of hypoventilation.

Adolescent↗
PubMed2004

Long-term pulmonary sequelae in children who were treated with extracorporeal membrane oxygenation for neonatal respiratory failure.

OBJECTIVE: Extracorporeal membrane oxygenation (ECMO) is a life-saving therapy for neonates with intractable respiratory failure, but the long-term pulmonary outcome is unknown. Our aim was to investigate the long-term pulmonary sequelae of these children. STUDY DESIGN: We studied 50 children at 11.1 +/- 1.1 years (mean +/- SD) who had been treated with neonatal ECMO for meconium aspiration syndrome (38%), sepsis (18%), sepsis with pneumonia (12%), congenital diaphragmatic hernia (12%), congenital heart disease (8%), persistent pulmonary hypertension of the newborn (6%), and respiratory distress syndrome (4%) and 27 healthy controls (10.8 +/- 1.6 years). All subjects completed a respiratory questionnaire and performed pulmonary function and graded cardiopulmonary exercise testing. RESULTS: Neonatal ECMO survivors had hyperinflation (median residual volume: 131%), airway obstruction (median forced expired volume in 1 second: 79%), lower oxygen saturation with exercise, and lower peak oxygen consumption than controls. The ECMO group achieved similar exercise minute ventilation to controls, with more rapid and shallow breathing. ECMO survivors had an increased frequency of exercise-induced bronchospasm. Those who required higher inspired oxygen tension and ventilator pressures after weaning from ECMO had lower forced expired volume in 1 second and oxygen saturation values. CONCLUSION: Neonatal ECMO survivors experience lung injury lasting into later childhood. Lung dysfunction correlates with the extent and duration of barotrauma and oxygen exposure as neonates.

Adolescent↗
PubMedDate not supplied

[The effect of rehabilitation procedures on pulmonary function in patients with chronic obstructive bronchitis].

Modern treatment of patients with chronic obstructive bronchitis consists of a parallel and simultaneous carrying out of medicinal treatment and appropriate rehabilitation. The authors studied the effect of rehabilitation on the pulmonary function in 31 patients (rehabilitation group A-1) with chronic obstructive bronchitis within three weeks (position drainage on the oscillation table and vibro-message for 15-30 min. after aerosol-therapy, and respiratory diaphragmatic exercises). The control group was composed of 30 patients (medical group A-2) with chronic obstructive bronchitis treated with medicaments only. On the basis of the results before and after the treatment, the authors established that only group A-1 patients showed, at the end of treatment, a statistically greater forsed expiratory volume in the first second, reduced thoracic gas volume, reduced specific resistance and increased lung conduction in airways.

Bronchitis↗
PubMed2002

Correlation of high signal intensity of the pituitary stalk in macroadenoma and postoperative diabetes insipidus.

BACKGROUND AND PURPOSE: High signal intensity (HSI) at the pituitary stalk is reported in pituitary adenomas. Our purpose was to clarify how and when this HSI formed, its long-term fate, and its relation to the function of infundibuloneurohypophyseal (INH) system. METHODS: Twenty-two patients with pituitary adenoma and supradiaphragmatic extension underwent 1.5-T MR imaging. Patients were assigned to two groups A (n = 18; those with stalk tip HSI) and B (n = 4; those without HSI) on postoperative T1-weighted images. Endocrine status was postoperatively evaluated and compared in both groups. RESULTS: Group A patients did not have postoperative permanent diabetes insipidus (DI). Preoperative images in 17 patients revealed linear or ovoid HSI on the adenoma surface immediately above the diaphragma sellae. Of these, two with a poorly developed diaphragma sellae had HSI near the median eminence and inside the sella turcica. HSI was not apparent in the remaining patient with a giant, irregularly shaped adenoma. In group B, three patients had permanent DI. No patient had HSI on preoperative images. CONCLUSION: Postoperative pituitary stalk HSI is derived from preoperative supradiaphragmatic HSI on the adenoma surface. The suspected mechanism is blockage of the hypophyseal-pituitary axis, with an accumulation of neurosecretory granules at the diaphragmatic level. Diaphragmatic shape may influence the location of HSI. The shape and location of HSI are essentially stable for years after surgery. No patients with permanent DI had HSI before or after surgery. HIS at the pituitary stalk tip is a useful landmark for predicting functional integrity of the INH system in patients with a large pituitary adenoma.

Adenoma↗
PubMed1997

Long-term pulmonary sequelae in children with congenital diaphragmatic hernia.

Neonates with congenital diaphragmatic hernia (CDH) often suffer from respiratory insufficiency due to lung hypoplasia and pulmonary hypertension. Artificial ventilation is frequently required, and this leads to a high incidence of bronchopulmonary dysplasia. Long-term follow-up studies have shown persisting airway obstruction. To evaluate the long-term pulmonary sequelae in CDH, we studied 40 CDH patients of age 7 to 18 yr (median 11.7 yr) and 65 age-matched controls without CDH and lung hypoplasia who underwent similar neonatal treatment. Mild airway obstruction was found in both groups with more peripheral airway obstruction in CDH patients than in control subjects. Both groups had normal TLC and single-breath carbon monoxide diffusion capacity (DLCO). CDH patients had increased residual volume (RV) and RV/TLC compared with controls. Increased airway responsiveness to methacholine (MCH) was common but bronchoconstriction to inhaled metabisulfite (MBS) was rare both in CDH and control subjects. We conclude that this group of CDH patients has minor residual lung function impairment. Mild airway obstruction and increased airway responsiveness to inhaled MCH but not to MBS suggest that structural changes in distal airways are involved and not autonomic nerve dysfunction. Both artificial ventilation in the neonatal period and residual lung hypoplasia seem important determinants of persistent lung function abnormalities in CDH patients.

Adolescent↗
PubMed1994

Three-dimensional reconstruction of the in vivo human diaphragm shape at different lung volumes.

The ability of the diaphragm to generate pressures at different lung volumes (VLs) in humans may be determined by the following factors: 1) its in vivo three-dimensional shape, radius of curvature, and tension according to Laplace law; 2) the relative degree to which it is apposed to the rib cage (i.e., zone of apposition) and lungs (i.e., diaphragm dome); and 3) its length-force properties. To gain more insight into these factors we have reconstructed from nuclear magnetic images the three-dimensional shape of the diaphragm of four normal subjects under supine relaxed conditions at four different VLs: residual volume, functional residual capacity, functional residual capacity plus one-half of the inspiratory capacity, and total lung capacity. Under our experimental conditions the shape of the diaphragm changes substantially in the anteroposterior plane but not in the coronal one. Multivariate regression analysis indicates that the zone of apposition is dependent on both diaphragm shortening and lower rib cage widening with lung inflation, although much more on the first of these two factors. Because of the changes in anteroposterior shape and expansion of the insertional origin at the costal margin with lung inflation, the data therefore suggest that the diaphragm may be more accurately modeled by a "widening piston" (Petroll's model) than a simple "piston in a cylinder" model. A significant portion of the muscular surface is lung apposed, suggesting that diaphragmatic force has radial vectors in the dome and vectors along the body axis in the zone of apposition. The muscular surface area of the diaphragm decreased linearly by approximately 41% with VL from residual volume to total lung capacity. Diaphragmatic fibers may shorten under physiological conditions more than any other skeletal muscle. The large changes in fiber length combined with limited shape changes with lung inflation suggest that the length-twitch force properties of the diaphragm may be the most important factor for the pressure-generating function of this respiratory muscle in response to bilateral phrenic shocks at different VLs.

Diaphragm↗