PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “atrial biopsy”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2026

Histological Determinants of Atrial Dysfunction in Patients With Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) is associated with diverse histological abnormalities, but their contributions to atrial dysfunction and functional recovery remain unclear. METHODS: In a discovery cohort of 375 patients with nonvalvular AF undergoing catheter ablation, atrial biopsy samples were quantitatively analyzed for fibrosis, intercellular space expansion, myofibrillar loss, myocardial nuclear density, and amyloid deposition. Left atrial reservoir strain (LASr) was assessed as a measure of atrial function during sinus rhythm (Group 1) or AF (Group 2) at the time of echocardiography. Functional recovery was defined as the change in LASr 12 months after ablation. Findings were validated in an independent cohort of 191 patients with AF. A subset of samples was additionally analyzed for DNA damage markers, poly(ADP-ribose), and phosphorylated histone H2A.X. RESULTS: LASr improved significantly after ablation in Group 2 but not in Group 1. Multivariable analyses identified greater fibrosis, reduced myocardial nuclear density, and advanced amyloid deposition as significant determinants of impaired atrial function in both groups and of limited postablation functional recovery in Group 2 (all P<0.01). Amyloid deposition was also significantly associated with adverse clinical outcomes. Decision-tree models incorporating LASr accurately identified advanced amyloid deposition in both cohorts (accuracy, 94%-96%). DNA damage markers were inversely associated with myocardial nuclear density and positively associated with cardiomyocyte hypertrophy. CONCLUSIONS: Fibrosis, DNA damage-associated reduction in myocardial nuclear density, and advanced atrial amyloidosis are key determinants of atrial dysfunction and impaired postablation functional recovery in patients with AF. LASr enables noninvasive identification of advanced atrial amyloidosis.

Humans↗
PubMed1977

Studies on digitalis. X. Digitoxin metabolites in human myocardium and relationship between myocardial and serum concentrations of digitoxin in patients on maintenance treatment.

The levels of digitoxin and cardioactive metabolites were measured in 42 atrial biopsies with a 86Rb method modified for analysis of myocardial samples. The mean value was 91.0 ng/gm wet weight (SD 54.4). Myocardial and serum concentrations were compared in 23 patients; there was no significant correlation. The ratio of total drug concentration in myocardium and serum ranged from 1 to 38 with a mean value of 5.4. Calculated from the free drug concentrations, the mean myocardial serum ratio was 200, which reflects the high affinity of digitoxin and cardioactive metabolites to the myocardium. The metabolic pattern of cardioactive and inactive metabolites (conjugates with glucuronic and sulfuric acid) was studied in autopsy samples from left ventricular myocardium from 7 patients. Significant differences between the myocardial and serum patterns of cardioactive and inactive metabolites were demonstrated. The myocardium contained less unchanged digitoxin (25.7%) and more hydrolyzed (55.4%) and conjugated (54.1%) metabolites than serum (57.6%, 31.0%, and 33.1%, respectively). Hydroxylated metabolites in myocardium (15.8%) were not significantly changed compared to serum (10.0%).

Adult↗
PubMedDate not supplied

[Electrophysiological studies in permanent atrial paralysis].

Permanent atrial paralysis is a very rare entity characterized by absence of electrical and mechanical activity of the atria which persists for months or years. We present a patient with congestive cardiomyopathy and chronic atrial paralysis. The phonomechanocardiographic study confirmed the absence of mechanical contraction of the atrium and did not show atrial electrical activity in the superficial electrocardiogram nor in the intracavitary tracing. In the electrophysiological study of the biopsy of the atrial myocardium an unexcitable tissue was found with an important diastolic despolarization of 30 mv. The histologic and ultrastructural studies showed nonspecific changes, with the replacement of the myocardial cells by fibrous tissue.

Heart Atria↗
PubMed1976

Technique for serial right and left ventricular endocardial biopsy in dogs.

A method is described for obtaining left and right ventricular endocardial biopsies repeatedly over a period of 3-6 mo in the dog. The left ventricular endocardial biopsy technique consists of the placement of a catheter via the venous route across the atrial septum and into the left ventricle. The biopsy catheter is in turn placed within this transseptal catheter. Tissues obtained by this method were satisfactory for both light and electron microscopic examination. At postmortem examination, only minimal and insignificant damage existed at the biopsy site. Consequently, we recommend this technique for the study of progressive pathologic changes in the endocardium that occur during the course of an experiment which can be identified and quantified in comparison to the control state.

Animals↗
PubMedDate not supplied

Production of experimental atrial septal defects.

Atrial septal defects (ASDs) were successfully created by punch biopsy technique in 67 dogs. The technique is simple, effective and provides an ideal model for the study of ASDs, either for testing closure devices or physiological experiments. The position and size of the defects may be varied according to preference. Of 45 animals subjected to cardiac catheterization, 39 (87 percent) has a patent atrial septal defect.

Animals↗
PubMed1978

Advances in invasive cardiac diagnosis and management.

Cardiac catheterization is now a relatively safe procedure when performed by an experienced pediatric cardiology team in a medical center with full ancillary pediatric services as well as cardiac surgery available on a 24 hour basis. Advances in equipment and techniques such as improved radiological equipment, newer catheters, and angled angiocardiographic views have improved diagnostic studies such that intraoperative changes in the preoperative diagnoses fortunately are rare. The use of prostaglandin E1 in neonates with either pulmonary atresia or the coarctation syndrome to achieve ductal dilatation with resultant marked clinical improvement preoperatively is a major advance that should become a standard method of therapy over the next few years. Newer catheterization techniques include devices for enlarging atrial septal defects (balloons and blades), closing atrial septal defects, closing a patent ductus, and performing myocardial biopsies in infants. All of these latter techniques hold promise for extending the pediatric cardiologist's role in providing newer diagnostic as well as therapeutic techniques in the care of infants and children with heart disease.

Adolescent↗
PubMed1979

Cardiac abnormalities in myotonic dystrophy. Electrophysiologic and histopathologic studies.

Eight young adult male patients with myotonic dystrophy, mean age 26 years, underwent 24-hour Holter electrocardiographic monitoring and intracardiac electrophysiologic study. Right ventricular endomyocardial biopsies were performed at the end of the electrophysiologic study in five of them. The atrial to His[A-H] interval was 155 msec in one case and less than or equal to 55 msec in all patients. Twenty-four hour Holter electrocardiographic monitoring demonstrated more than 4 premature ventricular contractions per minute in two patients and marked cyclical sinus arrhythmia during sleep in two others. Electron microscopic analysis of the endomyocardial biopsy specimens disclosed no prominent sarcoplasmic reticulum abnormalities but prominent I bands compared to previously obtained controls. Myofibrillar degeneration was seen in all cases and was associated with abnormal mitochondria in two. Cardiac abnormalities can be detected very early in the evolution of myotonic dystrophy, even prior to the onset of cardiac symptoms. The reported abnormalities appear closely related to the pathologic process affecting other skeletal muscles.

Adolescent↗
PubMed1976

Spherical microparticles in human myocardium: an ultrastructural study.

Clusters of spherical microparticles (SMP) that averaged 500 A in diameter and were composed of dense cores surrounded by single trilaminar membranes were found in operatively obtained myocardial biopsies from 29 of 70 patients with various types of heart diseases including: left atrial myocardium (14 patients) and right atrial myocardium (four patients) of 14 patients with mitral valvular disease; left ventricular myocardium of three of 16 patients with aortic valvular disease, three of 16 patients with hypertrophic cardiomyopathy, and two of four patients with combined mitral and aortic valvular disease; and crista supraventricularis muscle of seven of 20 patients with congenital heart diseases associated with muscular obstruction to right ventricular outflow. SMP were consistently associated with interstitial fibrosis and with degeneration of the muscle cells. SMP occurred along the outer surfaces on the sides and free ends of muscle cells in areas of fibrosis, in the widened spaces between membranes of partially dissociated intercellular junctions, and within cytoplasmic vesicles considered to be phagocytic. SMP frequently were joined together by minute nexuses that were structurally identical with those forming parts of intercellular junctions of muscle cells. Evidence is presented to show that SMP occur commonly in tissues other than myocardium. It is concluded that SMP form in the heart as part of a process that mediates the remodeling of cellular surfaces, especially those of intercellular junctions undergoing dissociation.

Cardiomegaly↗
PubMed1979

[Disorders of myocardial contractile capacity in patients with an interatrial septal defect complicated by bacterial endocarditis].

After performing 242 operations on patients with secondary atrial septal defects under conditions of moderate hypothermia, the authors studied the contractile capacity of the myocardium by means of long-term catheterization of the heart chambers in 56 patients. In 35 patients of this group intravital biopsy of the right ventricle was carried out. The bioptic material was subject to light and electron microscopy and histochemical examination. Considerable changes in intracardiac hemodynamics were revealed in patients with bacterial endocarditis. In such cases the diastole changes most sharply: the phase of isometric relaxation was prolonged, and there was a sharp rise in the maximum rate of intraventricular pressure decrease and in the relaxation index, which indicated to disorders of metabolic processes in the myocardium, conducive to the manifestation of myocardial insufficiency.

Adolescent↗
PubMed2025

Horse model of spontaneous atrial fibrillation share proteomic changes with humans.

Horses and humans are among the few mammals susceptible to spontaneous atrial fibrillation (AF), both suffering from high recurrence rates after treatment. Treatment resistance is often attributed to progressive atrial remodeling, but current treatment options fail to effectively address this aspect. Here, we introduce a novel horse model of spontaneous AF to investigate the biological pathway changes in early stages of the disease. Through data-independent acquisition mass spectrometry on biopsies from the right and left atrium and left ventricular chamber of horses with early-stage persistent AF (n&#x2009;=&#x2009;8) and controls (n&#x2009;=&#x2009;8), we identify several differentially regulated proteins across all three chambers. Pathway enrichment analyses and histological stainings highlight a significant role of atrial extracellular matrix (ECM) remodeling in early AF. Other key proteomic changes relate to metabolism, contractility, and protein-folding, and overlap with findings from publicly available human datasets. Our results demonstrate that horses and humans share several AF-related proteomic changes, providing translational insights into the early atrial remodeling processes that are likely to contribute to treatment resistance. These protein-level changes could serve as biomarkers or pharmacological targets for preventing AF-associated atrial remodeling and improve treatment outcomes across species.

Atrial Fibrillation↗
PubMed1976

[Plasma level of complement fractions C3 and C4 in children with glomerular nephropathies. Correlations with morphological and immunopathological studies of renal biopsies].

The measurement of the plasmatic level of C3 may easily be included in the record of all glomerular nephropathies. Its decrease is an important argument for the diagnosis of post-infectious acute glomerulonephritis, or renal involvement in sepsis supervening to a ventriculo-atrial diversion. Variations of C3 level are of major importance in the management of the nephropathies in systemic lupus. Besides these special etiological circumstances, a persisting low level of C3 most often cooresponds to a membrano-proliferative glomerulonephritis especially of the type characterized by intra-membranous dense deposits.

Adolescent↗
PubMed1977

Right atrial myxoma with right to left shunting and mitral valve prolapse.

A 58 year old black man presented with progressive dyspnea and persistent systemic arterial hypoxemia. Initial hemodynamic evaluation revealed mitral valve prolapse and evidence for isolated right to left shunting, presumed to be extracardiac. A detailed pulmonary evaluation disclosed normal volume and flow parameters with a mild reduction of the single breath carbon monoxide diffusing capacity. An open lung biopsy disclosed no abnormalities. Radionuclide studies of the heart, however, suggested the possibility of a filling defect in the right atrium, and echocardiography enforced the impression of a mass in the right atrium, subsequently demonstrated by superior vena cava angiography. Our report outlines the use of multiple diagnostic tools in difficult situations and stresses the importance of right atrial myxoma in the differential diagnosis of isolated right to left shunting

Echocardiography↗
PubMed1975

Cardiac features of an unusual X-linked humeroperoneal neuromuscular disease.

To characterize an unusual, sex-linked recessive neuromuscular disease, we studied two families with 37 males who had involvement of distal leg and proximal arm muscle groups. Electromyography and muscle biopsy in five subjects showed features of both neuropathy and myopathy. Bradycardia and syncope in 15 involved subjects were associated with early death (before the age of 50 years). Electrocardiograms in 15 others showed a spectrum of atrial abnormalities that ranged from abnormal P waves to permanent atrial paralysis and from first-degree atrioventricular block to complete heart block. No patient exhibited clinical muscle disease without electrocardiographic atrial disease. Dilated, hypertrophied left ventricles with normal indexes of function were found in three cases with permanent atrial paralysis and chronic junctional bradycardia. Cardiomegaly and cardiac failure were not present in the other cases. We conclude that permanent ventricular pacing (instituted four patients) is indicated in many of these patients to prevent serious sequelae.

Adult↗
PubMed1979

Sarcoma obstructing right ventricular cavity: clinical, echocardiographic, haemodynamic and angiographic features.

Right atrial hypertension and pericardial effusion developed 2 years after mastectomy for fibrosarcoma. Clinical and echocardiographic features suggested right ventricular tumour. At catheterization the right ventricular cavity was almost obliterated, with an infundibular gradient of 13 mmHg, and biopsy of the mass was attempted. Post-mortem revealed extensive infiltrating and intracavitary right ventricular fibrosarcoma without extracardiac tumour.

Echocardiography↗
PubMed1977

The protective effect of propranolol on ischemic myocardium: an electron microscopic study.

The protective effect of propranolol on ischemic myocardium was studied experimentally and clinically by electron microscope. In an animal experiment, ischemic changes were produced in the posterior papillary muscle of the rabbit following 3, 15, 30 minutes of occlusion of the circumflex coronary artery. Propranolol (0.25 mg/kg) was injected into the left atrial cavity before occlusion of the artery. The posterior papillary muscle was excised and examined by electron microscope. In clinical experience, propranolol (20 microng/kg) was given intravenously to 6 patients who underwent open heart surgery. Transmural left ventricular myocardial biopsy was performed after the anoxic cardic arrest and the material, particularly the subendocardium, was examined by electron microscope. It was shown that propranolol was effective, both in the experiment and in the clinical experience, in preserving ischemic myocardium. The possible mechanisms through which propranolol might act were considered to be (1) indirect effect of altered oxygen supply vs. demand, effect by reducing heart rate and reducing cardiac output due to the drug's function as a beta blocker, (2) direct cellular effect, i.e., reducing myocardial substrate metabolism along with stabilization of cellular structure, and (3) increase collateral circulation to the subendocardium.

Adolescent↗
PubMed1977

[Systemic lupus erythematosus and congestive heart failure. Heart histological and ultrastructural study (author's transl)].

Histological and ultrastructural studies were performed on myocardial biopsies and aortic and mitral valve leaflets obtained during an operation on a patient with Systemic Lupus Erythematosus (S.L.E.). Congestive heart failure and valvular dysfunction appeared five years after the diagnosis of S.L.E. was made. On histological study, aortic and mitral valve leaflets are uniformly thickened by fibrous tissue with a nodular appearance. No active endocarditis was associated with the fibrous scarring. Atrial myocardium and papillary muscle countain a fibrous net-work discret in the former, extensive in the latter. The scattered foci of fibrosis in the papillary muscle surround vessels without obliteration or parietal necrosis. Ultrastructurally their lumina appears narrowed by prominent endothelial cells with cytoplasmic aggregates of tubuloreticular structures (T.R.S.). These tubules are also present in some endocardial endothelial cells but are rare in the normal intrapapillary or atrial vessels that are not associated with a scar. Myocardial fibrous foci enclose atrophic and severely degenerated cardiac muscle cells; other cells situated at the periphery of the foci are normal in size or hypertrophic and moderately degenerated. The most altered muscle cells show an important loss of myofibrils, a proliferation of sarcoplasmic reticulum in myofibril free spaces, or necrosis with macrophagic resorption. Focal changes with loss of myofilaments, Z material streaming and concentric lamellar bodies are found in moderately degenerate cardiac muscle cells. The remaining papillary muscle cells and the atrial cells are all hypertrophied without degeneration. These changes suggest that focal myocardial fibrosis and associated cardiac muscle cell degeneration may be responsible for impaired cardiac performance in some patients with S.L.E. According to the constant topographic relation between the narrowed vessels whose endothelial cells contain T.R.S. and the surrounding fibrous foci, we believe that the myocardial fibrous patches may correspond to scarring of microinfarcts related to active S.L.E. vascularitis.

Aortic Valve↗