Two unique biological response-modifier glucans beneficially regulating gut microbiota and faecal metabolome in a non-alcoholic steatohepatitis animal model, with potential applications in human health and disease

Objective

The gut microbiome and its metabolites are influenced by age and stress and reflect the metabolism and health of the immune system. We assessed the gut microbiota and faecal metabolome in a static animal model of non-alcoholic steatohepatitis (NASH).

Design

This model was subjected to the following treatments: reverse osmosis water, AFO-202, N-163, AFO-202+N-163 and telmisartan treatment. Faecal samples were collected at 6 and 9 weeks of age. The gut microbiome was analysed using 16S ribosomal RNA sequences acquired by next-generation sequencing, and the faecal metabolome was analysed using gas chromatography-mass spectrometry.

Results

Gut microbial diversity increased greatly in the AFO-202+N-163 group. Postintervention, the abundance of Firmicutes decreased, whereas that of Bacteroides increased and was the highest in the AFO-202+N-163 group. The decrease in the abundance of Enterobacteriaceae and other Firmicutes and the abundance of Turicibacter and Bilophila were the highest in the AFO-202 and N-163 groups, respectively. Lactobacillus abundance was highest in the AFO-202+N-163 group. The faecal metabolite spermidine, which is beneficial against inflammation and NASH, was significantly decreased (p=0.012) in the N-163 group. Succinic acid, which is beneficial in neurodevelopmental and neurodegenerative diseases, was increased in the AFO-202 group (p=0.06). The decrease in fructose was the highest in the N-163 group (p=0.0007). Isoleucine and Leucine decreased with statistical significance (p=0.004 and 0.012, respectively), and tryptophan also decreased (p=0.99), whereas ornithine, which is beneficial against chronic immune-metabolic-inflammatory pathologies, increased in the AFO-202+N-163 group.

Conclusion

AFO-202 treatment in mice is beneficial against neurodevelopmental and neurodegenerative diseases, and has prophylactic potential against metabolic conditions. N-163 treatment exerts anti-inflammatory effects against organ fibrosis and neuroinflammation. In combination, these compounds exhibit anticancer activity.

Integrating the Synergy of the Gut Microbiome into Regenerative Medicine: Relevance to Neurological Disorders

A new paradigm of cell therapy-based approaches as a solution to several diseases caused by damage or loss of cells/tissues leading to organ failure heralded the birth of a new branch in medicine called regenerative medicine (RM), which was further fueled by in vitro cell expansion and tissue engineering (TE) technologies, including the ability to grow embryonic stem cells, induce pluripotent stem cells, and so on. RM addresses organ failure by repair, regeneration, or restoration, rejuvenation using cells, stem cells, or progenitor cells as tools having added cell-derived products also as a tool, and extracellular matrix component–based support, either direct or indirect (e.g., matrix induced autologous chondrocyte implantation) using scaffolds. Now, the main objective of RM is to solve the functional loss of cells that have evolved from cells as tools to cell-derived factors and scaffolds per se as tools. In this context, an important yet indispensable group of cells that constitute the major portion of the human body in terms of the number of cells having several essential roles to play, both directly and indirectly, starting from digestion and the immune system to the growing evidence of influencing neuronal function, aging, and carcinogenesis has been ignored. We would like to focus on these in this review as they should essentially be considered as a tool of RM, especially for neurological disorders for their vital role. What we are indicating is the second genome or the gut microbiome.

The Role of Dietary Fiber and Gut Microbiome Modulation in Progression of Chronic Kidney Disease

Nutrition is one of the fundamental approaches to promoting and preventing all kinds of diseases, especially kidney diseases. Dietary fiber forms a significant aspect of renal nutrition in treating chronic kidney disease (CKD). Dietary fiber intake influences the composition and metabolism of the gut microbiome with proven roles in reducing uremic toxin production, preserving kidney function, and retarding the progression of CKD through mechanisms of regulating metabolic, immunological, and inflammatory processes. Understanding dietary fiber’s pathogenesis and mechanistic action in modulating host and microbiome interactions provides a potential adjunct therapeutic target for preventing, controlling, and treating CKD patients. In this regard, a recommendation of adequate and appropriate dietary fiber intake to restore beneficial gut microbiota composition would reduce the risks and complications associated with CKD. This mini review summarizes current evidence of the role of dietary fiber intake in modulating the gut microbiome to improve kidney health.

Probiotic supplements prevented oxonic acid-induced hyperuricemia and renal damage

Hyperuricemia is highly prevalent and especially common in subjects with metabolic, cardiovascular and renal diseases. In chronic kidney disease, hyperuricemia is extremely common, and uric acid (UA) excretion relies on gut uricolysis by gut microbiota. Current therapy for lowering serum UA includes drugs that may produce undesired secondary effects. Therefore, this pilot study was designed to evaluate the potential of two probiotic supplements to reduce systemic uric acid concentrations. Secondary objectives were to assess whether the hypouricemic effect related to a therapeutic benefit on the hyperuricemia-induced renal damage and hypertension. Analysis of fecal microbiota was also performed. Groups of 6 rats each were followed for 5 weeks and allocated in the following treatment groups: C = Control; HU-ND = Oxonic acid-induced hyperuricemia (HU) +regular diet; HU-P = HU+placebo; HU-F1 = HU+ probiotics formula 1 and HU-F2 = HU+ probiotics formula 2. We confirmed that oxonic acid-induced hyperuricemia produced hypertension and renal functional and structural changes, along with modest changes in the overall composition of fecal microbiota. Both probiotic-containing diets prevented HU, elevated UA urinary excretion and intrarenal UA accumulation induced by oxonic acid. The hypouricemic effect conferred by probiotic supplementation also prevented the renal changes and hypertension caused by hyperuricemia. However, probiotic treatment did not restore the fecal microbiota. In conclusion, we demonstrated for the first time the ability of probiotics containing uricolytic bacteria to lower serum uric acid in hyperuricemic animals with beneficial consequences on blood pressure and renal disease. As probiotics supplements are innocuous for human health, we recommend clinical studies to test if probiotic supplements could benefit hyperuricemic individuals.

COMPARISON OF FATIGUE CRITERIA UNDER PROPORTIONAL AND NON-PROPORTIONAL MULTIAXIAL LOADING

Owing to their interesting mechanical behavior and their diversity, rubberlike materials are more and more used in the industry. Previous works (Poisson et al.) presented an important experimental investigation on the multiaxial fatigue of polychloroprene rubber, with both proportional and non-proportional combinations of tension and torsion loads (with a large range of loads and three different phase angles: 0°; 90°, 180°). A fatigue criterion, based on the dissipated energy density (DED) was introduced. Comparing this parameter to the most important criteria available on literature—which are the strain energy density (SED), the cracking energy density (CED), and the Eshelby tensor—in their accuracy allows one to predict fatigue life of rubberlike material. All the predictors are computed with an analytical viscoelastic model based on the kinematics of a combined tension and torsion loading applied on a cylinder. This cylinder represents the central part of the axisymetric dumbbell specimen, and the model was identified with a polychloroprene rubber. It is finally shown that the DED and CED reach more conclusive results, provided the structure, the material, and the loads investigated.

Metabolic profiling of a chronic kidney disease cohort reveals metabolic phenotype more likely to benefit from a probiotic

SCOPE

Persistent reduction in Glomerular Filtration Rate (GFR) is a hallmark of Chronic Kidney Disease (CKD) and is associated with an elevation of Blood Urea Nitrogen (BUN). This metabolomics pilot study sought to identify metabolites that differentiated patients with CKD whose BUN decreased on a probiotic and possible mechanisms.

METHODS AND RESULTS

Metabolomics was used to analyze baseline plasma samples previously diagnosed with CKD Stage III-IV. Patients had participated in a dose escalation study of the probiotic Renadyl™. A total of 24 samples were categorized depending on whether BUN increased or decreased from baseline after 4 months of probiotic use. Multivariate analysis was used to analyze the data and determine the metabolites that best differentiated the phenotypic groups. The sixteen patients who had a decrease in BUN were not significantly different based on demographic and clinical measures from those whose BUN increased or did not change with the exception of age. Eleven of the fourteen metabolites that differentiated the groups were known to be modulated by gut microflora, which may eventually provide a mechanistic link between probiotic and outcomes.

CONCLUSIONS

Metabolomics revealed metabolites at baseline that may predict individuals with CKD that would most benefit from a probiotics.

MULTIAXIAL FATIGUE CRITERIA APPLIED TO A POLYCHLOROPRENE RUBBER

Due to their interesting mechanical behavior and their diversity, rubber materials are more and more used in industry. Indeed, formulating a multiaxial fatigue criterion to predict fatigue lives of rubber components constitutes an important objective to conceive rubber products. An experimental campaign is developed here to study the multiaxial fatigue behavior of polychloroprene rubber. To reproduce multiaxial solicitations, combined tension–torsion tests were carried out on a dumbbell-type specimen (an axisymmetric rubber part bonded to metal parts with a reduced section at mid-height), with several values of phase angles between tension and torsion. A constitutive model is needed to calculate multiaxial fatigue criteria, and then analyze fatigue results. A large strain viscoelastic model, based on the tension–torsion kinematics, is then used to determine the material's stress–strain law. Dissipated energy density is introduced as a multiaxial fatigue criterion, and compared with those usually used in the literature. A multiaxial Haigh diagram is then built to observe the influence of Rd-ratio (ratio of the axial displacement's minimum to the axial displacement's maximum) on the multiaxial fatigue lives of polychloroprene rubber.

Pilot study of probiotic dietary supplementation for promoting healthy kidney function in patients with chronic kidney disease

INTRODUCTION

Uremic syndrome consists of nitrogenous waste retention, deficiency in kidney-derived hormones, and reduced acid excretion, and, if untreated, may progress to coma and eventual death. Previous experience suggests that oral administration of a probiotic formulation of selected microbial strains may extend renoprotection via intraintestinal extraction of toxic waste solutes in patients with chronic kidney disease (CKD)stages 3 and 4. This report presents preliminary data from a pilot study.

METHODS

This was a 6-month prospective, randomized, double-blind, placebo-controlled crossover trial of a probiotic bacterial formulation conducted in four countries, at five institutions, on 46 outpatients with CKD stages 3 an nd 4: USA (n=10), Canada (n=113), Nigeria (n=115), and Argentina (n=8). Outcomes were compared using biochemical parameters:blood urea nitrogen (BUN), serum creatinine, and uric acid. General well-being was assessed as a secondary parameter by a quality of life (QQOL) questionnaire on a subjective scale of 1-10.

RESULTS

Oral ingestion of probiotics (90 billion colony forming units [CFUs]/day) was well tolerated and safe during the entire trial period at all sites. BUN levels decreased in 29 patients (63%, P<0.05), creatinine levels decreased in 20 patients (43%, no statistical significance), and uric acid levels decreased in 15 patients (33%, no statistical significance). Almost all subjects expressed a perceived substantial overall improvement in QOL (86%, P<0.05).

CONCLUSION

The main outcomes of this preliminary trial include a significant reduction of BUN, enhanced well-being, and absence of serious adverse effects, thus supporting the use of the chosen probiotic formulation for bowel-based toxic solute extraction. QOL and BUN levels showed statistically significant differences in outcome (P<0.05) between placebo and probiotic treatment periods at all four sites (46 patients). A major limitation of this trial is the small sample size nd elated inconsistencies.

Probiotic dietary supplementation in patients with stage 3 and 4 chronic kidney disease: a 6-month pilot scale trial in Canada

AIM

This was a pilot clinical trial to assess biochemical and clinical effects of an oral probiotic dietary supplement in chronic kidney disease (CKD) patients (stages 3 and 4).

METHODS

A prospective, randomized, double-blind, crossover, placebo-controlled, 6-month trial of probiotic bacteria was conducted in 16 outpatients in Ontario, Canada. Primary endpoints included effect on hematologic, biochemical, and fecal variables, and on general well-being as assessed by quality of life (QOL). These outcomes were evaluated from biochemical parameters, mainly blood urea nitrogen (BUN), creatinine, uric acid, and C-reactive protein (CRP) as a general inflammatory marker. QOL was assessed on a subjective scale of 1 to 10 as the secondary parameter.

TRIAL REGISTRATION

This pilot study forms part of registered trial NCT00760162.

RESULTS

A total of 13 patients completed the study. Three patients dropped out: one was the receiver of a transplant. The second dropped out for unknown reasons and the third died of myocardial infarction (unrelated to probiotic bacteria or the protocol). Among the 13 patients who completed the trial, the mean change in BUN concentration during the probiotic treatment period (-2.93 mmol/L) differed significantly (p = 0.002) from the mean change in BUN concentration during the placebo period (4.52 mmol/L). In addition, the mean changes in uric acid concentration were moderate during the KB period (24.70 micromol/L) versus during the placebo period (50.62 micromol/L, p = 0.050), and the changes in serum creatinine concentration were insignificant. Neither gastrointestinal nor infectious complications were noted in any subject with improved QOL.

CONCLUSION

Orally administered probiotic bacteria selected to metabolize nitrogenous wastes may be tolerated for as long as 6 months. A major limitation of this trial is its small size that may have precluded detection of changes in other biochemical or hematologic parameters that would be evident in larger cohorts. Extension of the evaluation of this probiotic bacterial mixture will include a dose escalation trial in a similar prospective, placebo-controlled, and double-blind study site.

Probiotic amelioration of azotemia in 5/6th nephrectomized Sprague-Dawley rats

The present study was to test the hypothesis that selected bacteria instilled into the gastrointestinal tract could help in converting nitrogenous wastes accumulated due to renal insufficiency into nontoxic compounds; thereby, ameliorating the biochemical imbalance. Herein we describe a prospective, blinded, placebo-controlled pilot study, using 5/6^th nephrectomized Sprague Dawley rat as a chronic renal failure model. The study group consisted of 36 nephrectomized and 7 non-nephrectomized (control) rats. After two-week nephrectomy stabilization, cohorts of six nephrectomized rats were fed casein-based diet plus one of the following regimens: (A) Control, (B) Placebo (casein-based diet without probiotics), (C) Bacillus pasteurii, (D) Sporolac®, (E) Kibow cocktail, (F) CHR Hansen Cocktail, and (G) ECONORM^TM. Subsequently, blood (retro-orbital) and urine (collected for measurements of blood urea-nitrogen and creatinine respectively), body weight and bacterial counts (feces) were obtained at regular intervals. The study end-points were to determine if any of the probiotic dietary supplements facilitated, (1) decreased blood concentrations of uremic toxins, (2) altered renal function, and (3) prolonged survival. After 16 weeks of treatment, regimens C and D significantly prolonged the life span of uremic rats, in addition to showing a reduction in blood urea-nitrogen levels, concluding that supplementation of probiotic formulation to uremic rats slows the progression of azotemia, which may correlate with prolonged life span of uremic rats. Derivative trials of probiotic treatment of larger animals and humans will further assess the potential role of probiotic formulations in delaying the onset and clinical severity of clinical illness at different stages of renal failure.

In Vitro and In Vivo Assessment of Intraintestinal Bacteriotherapy in Chronic Kidney Disease

Chronic kidney disease may progress to end-stage renal disease, which requires dialysis or kidney transplantation. No generally applicable therapies to slow progression of renal disease are available. Bacteriotherapy affords a promising approach to mitigate uremic intoxication by ingestion of live microbes able to catabolize uremic solutes in the gut. The present study evaluates the nonpathogenic soil-borne alkalophilic urease-positive bacterium Sporosarcina pasteurii (Sp) as a potential urea-targeted component for such "enteric dialysis" formulation. Data presented herein suggest that Sp survives through exposure to gastric juice retaining the ability to hydrolyze urea. In vitro, 10 cfu (colony forming units) of Sp removed from 21 +/- 4.7 mg to 228 +/- 6.7 mg urea per hour, depending on pH, urea concentration, and nutrient availability. Beneficial effects of Sp on fermentation parameters in the intestine were demonstrated in vitro in the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) inoculated with fecal microbiota. Enumeration of marker organisms suggested that presence of Sp does not disturb microbial community of the SHIME. Additionally, a pilot study in 5/6th nephrectomized rats fed 10 cfu of live Sp daily throughout the study demonstrated that the tested regimen reduced blood urea-nitrogen levels and significantly prolonged the lifespan of uremic animals.

The accuracy and interobserver agreement in detecting the 'gallop sounds' by cardiac auscultation

STUDY OBJECTIVES

To determine the observer accuracy and interobserver agreement in identifying S4 and S3 by cardiac auscultation and whether they improve with increasing observer experience.

DESIGN

Prospective, blinded study.

SETTING

Cardiology and general internal medicine wards in a university-affiliated teaching hospital.

PATIENTS

Forty patients with a cardiac diagnosis and 6 patients without were studied.

MEASUREMENTS AND RESULTS

Two cardiologists, one general internist, three senior and two junior postgraduate internal medicine trainees, blinded to the patients' characteristics, examined the patients and documented their findings on a questionnaire. Computerized phonocardiogram was obtained in all patients as a gold standard and was interpreted by a blinded, independent cardiologist. The mean positive predictive values for S4 and S3 were 51% (range, 24 to 100%) and 71% (range, 50 to 88%), respectively. The mean negative predictive values for S4 and S3 were 82% (range, 67 to 94%) and 64% (range, 56 to 85%), respectively. The overall interobserver agreements for detecting S4 was K = 0.05 (95% confidence interval [CI], 0.01 to 0.09) and S3 was K = 0.18 (95% CI, 0.13 to 0.24). There was no apparent trend in the accuracy or interobserver agreement with regard to the level of observer experience.

CONCLUSION

The agreement between observers and the phonocardiographic gold standard in the correct identification of S4 and S3 was poor and the lack of agreement did not appear to be a function of the experience of the observers. The overall interobserver agreement for the detection of either S4 or S3 was little better than chance alone.

Adaptive VBR video traffic management for higher utilization of ATM networks

The VBR video traffic exhibits high burstiness and correlation properties that are quite complex to be captured by a single traffic model. Efficient resource management based on few parameters of the source traffic is highly desirable. The real-time VBR video traffic has stringent quality of service (QoS) requirements such as delay (few milliseconds) and cell loss (1 in 10 -5 ) that are difficult to achieve with good utilization (&gt; 0.6) by static bandwidth allocation schemes. In order to satisfy such QoS constraints with good utilization, proper adaptive mechanisms have to be devised. This paper presents a dynamic bandwidth allocation scheme for VBR video traffic based on buffer monitoring and a simple LMS (least mean square) traffic prediction system. The goal is to reduce the frequency of the bandwidth reallocations and at the same time reduce the Cell-loss Ratio (CLR) with increased utilization. Simulation results indicate that utilization up to 0.8 can be achieved by the proposed scheme even under high source alignment [26] for bursty VBR video traffic. It is found that the proposed adaptive scheme outperforms the static FCFS allocation scheme with lower buffer requirements and fewer (&lt; 5%) bandwidth reallocations.

A lossless image compression algorithm using variable block size segmentation

The redundancy in digital image representation can be classified into two categories: local and global. In this paper, we present an analysis of two image characteristics that give rise to local and global redundancy in image representation. Based on this study, we propose a lossless image compression scheme that exploits redundancy both at local and global levels in order to obtain maximum compression efficiency. The proposed algorithm segments the image into variable size blocks and encodes them depending on the characteristics exhibited by the pixels within the block. The proposed algorithm is implemented in software and its performance is better than other lossless compression schemes such as the Huffman, the arithmetic, the Lempel-Ziv and the JPEG.

Changes in jugular venous flow velocity after coronary artery bypass grafting

The factors underlying postoperative jugular venous flow velocity and pulse contour changes were studied in 25 patients undergoing coronary artery bypass grafting. Before operation, all patients had normal right-sided cardiac hemodynamics, normal jugular pulse contours and normal jugular venous flow velocity patterns, i.e., systolic flow (SF) velocity greater than diastolic flow (DF) velocity. After operation, jugular venous flow velocity was abnormal in 24 patients (SF = DF in 14 and SF less than DF in 10). Neither the right-sided cardiac pressures after the operation nor any of the perioperative factors examined had any bearing on these flow alterations. Postoperative right ventricular ejection fraction was normal in all 5 patients with SF greater than DF and SF = DF flow patterns (mean +/- standard error of the mean 48 +/- 3%). It was significantly depressed in all 6 patients with SF less than DF flow pattern (34 +/- 1%, 2p less than 0.001). These findings suggest that the right atrium behaves as a conduit rather than a capacitance chamber. However, the postoperative abnormal flow pattern of SF less than DF as opposed to SF = DF indicates the additional presence of right ventricular dysfunction. The implications of these observations for the clinical assessment of right ventricular function in the postoperative patients are discussed.

Abnormalities in jugular venous flow velocity in pulmonary hypertension

Doppler recordings of jugular venous flow velocity previously performed in this laboratory in patients with pulmonary hypertension had shown variations from the normal dominant systolic flow (SF) greater than diastolic flow (DF), to SF = DF, SF less than DF or DF alone. The mechanisms underlying these flow alterations were studied in 25 patients and correlated with hemodynamics. The patients with abnormal flow patterns had increased right atrial V-wave pressures. This was associated with an increased right ventricular early diastolic pressure. The incidence of clinical heart failure was higher in patients with SF less than DF or DF alone (8 of 11) compared with 5 of 10 patients with SF = DF. Thus, in patients with pulmonary hypertension, the abnormal jugular venous flow patterns appear to be caused by both an increased DF velocity and a decrease in SF velocity. Because the right atrial V-wave pressures were similar in patients with both SF = DF and SF less than DF or DF alone and the incidence of heart failure was higher in the latter, the decrease in SF must be a later phenomenon. Serial observations confirmed this temporal sequence. The applicability of these observations to bedside evaluation of patients with pulmonary hypertension is emphasized.

Prophylaxis of post-myocardial infarction dysrhythmias by long-term timolol therapy

The antiarrhythmic efficacy of timolol maleate was assessed in 94 patients with acute myocardial infarction. No significant differences were noted between early treatment with timolol and placebo in the mean and peak hourly ventricular premature complex rates, ventricular premature complex couplets, or runs. However, compared to the placebo treatment, there was a significant (p less than 0.001) 66% reduction in the relative fraction of early-cycle ventricular premature complexes 7 to 9 days after initiation of timolol therapy and a more prolonged significant (p less than 0.001) 73% reduction in the fraction of early-cycle supraventricular complexes throughout the 28-day timolol and placebo comparison period. The frequency distribution of QRS duration was significantly different between the placebo- and timolol-treated patients, with the mean duration 8 msec longer in the placebo-treated patients (p = 0.008). Adverse effects from early administration of timolol did not differ from those in the placebo-treated patients.

Sarcoidosis simulating pulmonary veno-occlusive disease

We describe a young woman who presented with a 6-month history of progressive pulmonary hypertension. At autopsy she was found to have noncaseating granulomas obliterating pulmonary veins, without granulomatous involvement of pulmonary arteries. Noncaseating granulomas were also present in the liver and hilar lymph nodes, confirming the diagnosis of sarcoidosis. To our knowledge this is the first reported case of pulmonary hypertension caused by sarcoidosis simulating pulmonary veno-occlusive disease.

The apical impulse in coronary heart disease

Forty patients (36 with coronary artery disease), who had angiographic assessment of left ventricular function were studied using apexcardiography with a new method of standardization, the objective being to define the parameters of the apical impulse which reflect changes in the left ventricular function and correlate them with clinical assessment of the apical impulse. Based on measurements from patients with normal left ventricular function, abnormalities in apexcardiograms were identified. An increase in amplitude of percent A wave alone (greater than 13.3%) (palpable as an atrial kick in approximately half of these patients) was not associated with significant left ventricular dysfunction. An isolated abnormality in isovolumic slopes, although associated with mild left ventricular dysfunction, could not be detected clinically. Moderate to severe left ventricular dysfunction was always associated with abnormal ejection phase slopes and all had sustained apical impulses. The additional presence of a palpable atrial kick or an increased percent A wave on the apexcardiogram was more indicative of moderate rather than severe dysfunction. Thus this study clearly establishes that left ventricular function does in fact affect the nature of the apical impulse in patients with coronary artery disease and these can be easily defined.

Management of a malignant hyperthermia patient during cardiopulmonary bypass

The anaesthetic management of cardiopulmonary bypass (CPB) for a patient with biopsy-proven malignant hyperthermia is reported. Specific changes in the technique used, such as venting the oxygenator before use, monitoring mixed venous PO2 and PCO2, as well as the safety of cold hyperkalaemic cardioplegia are described. Controversial aspects of malignant hyperthermia management such as the safety of calcium and catechol inotropes are discussed in relationship to the successful use of cardio-pulmonary bypass in our patient. We chose to treat left ventricular dysfunction by aggressive vasodilator (nitroglycerine) therapy. We detected no myocardial or respiratory depression secondary to dantrolene therapy either before or after operation.

Transcutaneous doppler jugular venous flow velocity recording

Transcutaneous bidirectional Doppler jugular venous flow velocity patterns were classified and correlated in 82 patients with right heart hemodynamics. The normal forward flow pattern was biphasic with systolic flow (Sf) greater than the diastolic flow (Df). With rare exceptions, flow patterns of Sf = Df, Sf is less than Df and Df alone indicated abnormal right heart hemodynamics. Abnormal flow patterns (Sf = Df and Sf is less than Df) seen in post cardiac surgery states, and in some rare patients with severe mitral regurgitation despite normal right-sided pressures, were probably secondary to postoperative change in right atrial compliance in the former and to a Bernheim effect in the latter. The most common cause of retrograde systolic flow in the absence of atrioventricular dissociation was tricuspid regurgitation. Persistent retrograde end-diastolic flow with normal forward flow was associated with high right atrial "a" wave pressures, indicating significant decrease in right ventricular compliance with a vigorous atrial contraction. The study clearly established that the jugular venous flow velocity pattern truly reflected derangements in the right heart hemodynamics, irrespective of the underlying etiology. The applicability to bedside evaluation of the jugular venous pulse and the right heart hemodynamics is emphasized.

Congenital intracardiac band: a rare cause of nonrheumatic combined aortic and mitral regurgitation

A patient had a congenital intracardiac band lying across the aortic valve that caused combined aortic and mitral valvular regurgitation. The band was excised, and the damaged aortic valve was replaced with a prosthesis. The case illustrates that not all congenital intracardiac bands are completely asymptomatic and not all bivalvular incompetence is rheumatic in origin.

Idiopathic prolapsed mitral leaflet syndrome. Angiographic-clinical correlations

Angiographic clinical correlations were made in 59 patients with prolapsed mitral leaflet syndrome. Eight had nonejection systolic clicks (group I), 20 had early, mid or late systolic murmurs with or without a systolic click (group II), and 31 had pansystolic murmurs (group III). Isolated prolapse of posterior leaflet (PL) scallops occurred in 42 and 17 had combined leaflet prolapse. The study demonstrated the following: (I) Group II patients usually had isolated PL prolapse with a predominant biscallop involvement while a high incidence of triple scallop prolapse and combined mitral leaflet prolapse occurred in group III. (II) Severe mitral regurgitation and a greater incidence of atrial fibrillation were seen in patients with triscallop prolapse and combined mitral leaflet prolapse. Mitral regurgitation was milder in patients with single and biscallop prolapse and, when severe, was associated with ruptured chordae. (III) ST-T wave abnormalities in the inferior leads were most frequent in patients with isolated PL prolapse. (IV) Systolic and diastolic asynergy occurred in 41 patients, most frequently in group II but also relatively frequently in group III (19 of 31). Segmental anterior dysfunction with normal ejection fraction was found in 18 patients, of whom 13 had early anterior wall relaxation. (V) Patients without asynergy were slightly older than those with it. More in the former group had severe mitral regurgitation and were clinically disabled from it.

Mitral valve prolapse

Mitral valve prolapse is a condition that is being recognized with increased frequency. It is not known whether its incidence is increasing, or whether we are better able to diagnose it today. In the idiopathic or familial variety, the mitral valve pathology is almost always that of myxomatous degeneration. Some authors have suggested the presence of a cardiomyopathy because of significant left ventricular dysfunction in many cases. Idiopathic prolapse occurs predominantly in females, often at a young age, and may be associated with chest pain, dyspnea, fatigue, presyncope, syncope, and/or sudden death. The clinical findings are variable and typically consist of a nonejection click and/or late systolic murmur, heard best at the cardiac apex. Diagnosis can be confirmed by echocardiography and/or ventricular cineangiography, the latter permitting accurate recognition of the anatomy of the prolapsed leaflets. The complications of infective endocarditis, severe mitral insufficiency, and life-threatening ventricular arrhythmias represent the major problems of management. It is important to distinguish the idiopathic form of mitral valve prolapse from that due to coronary artery disease and to realize that mitral valve prolapse may occur in Marfan's syndrome, Turner's syndrome, or in association with secundum atrial septal defect or ruptured chordae tendineae. Typical clicks and/or murmurs have also been described in patients with a history of rheumatic fever and in hypertrophic cardiomyopathy. Although much descriptive knowledge has accumulated over the past 15 years, many unanswered questions remain regarding the idiopathic type of prolapse. What is the nature and cause(s) of myxomatous degeneration? What is the relation of the valve pathology to the left ventricular dysfunction? What is the relation of both of these factors to disabling chest pain, electrocardiographic changes, and life-threatening arrhythmias? Hopefully, answers to these and other important questions regarding mitral valve prolapse will be forthcoming.

Angiographic-morphologic correlation in patients with severe mitral regurgitation due to prolapse of the posterior mitral valve leaflet

Angiographic-morphologic correlation was done on findings in 16 patients with proven prolapse of the posterior mitral leaflet and severe mitral regurgitation. A triscalloped bulge into the left atrium in the left ventriculogram taken in the right anterior oblique projection is caused by prolapse of all three scallops of the posterior mitral leaflet. The prolapsed middle scallop produces a central bulge, the prolapsed posteromedial commissural scallop a posteroinferior bulge ih tne area of the posteromedial commissure, and the prolapsed anterolateral commissural scallop an anterosuperior bulge in the anterolateral commissural area. The latter is often overlapped by the aortic root but if prominent, juts beyond it. Correlation proved that the diagnosis of individual scallop prolapse in this syndrome can be made accurately despite gross mitral regurgitation.

His Bundle electrogram in bundle-branch block

Because a great majority of patients with chronic complete heart block have bilateral bundle-branch lesions, it becomes important to recognize earlier degrees of bilateral bundle-branch block. The H-V interval in the His bundle electrogram during unilateral bundle-branch block reflects the conduction primarily through the contralateral bundle branch, and thus the His bundle electrogram in bundle-branch block (BBB) provides information regarding the functional status of the contralateral bundle branch in addition to helping in the localization of defects elsewhere in the conduction system.

His bundle electrograms were obtained in 20 patients with BBB and 13 patients without BBB. The following results were obtained from this study: (1) Prolonged P-R interval in the absence of BBB indicated delayed conduction through the A-V node. (2) Prolonged P-R interval in the presence of BBB indicated delayed conduction through the contralateral bundle branch or through the A-V node, or both. (3) Delayed conduction through the contralateral bundle branch in BBB occurred in the presence of a normal P-R interval and could only be detected by demonstrating a prolonged H-V time in the His recording. (4) In alternating BBB the His recording clearly demonstrated that the changing P-R interval was related to varying conduction through the bundle branches. (5) Finally, it has been demonstrated that the Wenckebach (Mobitz type I) type of decremental conduction can occur in the bundle branches or Purkinje system as well as in the A-V node.

It is concluded that His bundle electrograms provide valuable information concerning the nature and management of conduction disturbances in patients with bundle-branch disease.

Morphology of the human tricuspid valve

The morphology of 50 normal tricuspid valves was studied. The surface of the leaflets was divided into three zones: (1) the rough zone, into which most of the chordae tendineae are inserted, (2) the basal zone, and (3) the clear zone, which lies between the rough and basal zones.

Five types of chordae were distinguished by their morphology and mode of insertion: fan-shaped, rough zone, basal, free edge, and deep chordae. The last two types are unique to the tricuspid valve.

If fan-shaped chordae, used to define the commissures between the leaflets, are absent, other landmarks may be used for commissural definition. Once defined, all tissue between the commissures was regarded as part of the anterior, posterior, or septal leaflet. The recognition that the free edges of the anterior and septal leaflets contain notches, that rough zone chordae insert into them, and that the posterior leaflet has scallops further aids identification of a leaflet's components. Thus, structures formerly regarded as accessory leaflets were incorporated into one of the three leaflets.

Morphology of the human mitral valve. I. Chordae tendineae: a new classification

Chordae tendineae from 50 normal mitral valves were studied. Four main types can be distinguished by their mode of insertion. Commissural chordae insert into and define the commissures between the anterior and posterior leaflets. Rough zone chordae insert into the ventricular aspect of the distal rough portion of the anterior and posterior leaflets. Such rough zone chordae typically split into three cords before inserting into the leaflet. Two of the anterior leaflet rough zone chordae are thicker than the others and are called strut chordae. They insert at 4 and 8 o'clock positions on the semicircular anterior leaflet. Cleft chordae insert into and define the clefts between the scallops of the posterior leaflet. Basal chordae are single strands that arise from the posterior ventricular wall and insert into the basal zone of the posterior leaflet. This classification permits a clear definition of mitral valve anatomy and forms a sound basis for functional studies of chordae tendineae.