Parenting stress in mothers of children with an intellectual disability: the effects of parental cognitions in relation to child characteristics and family support

BACKGROUND

Recent theories of stress and coping in parents of children with intellectual disabilities (ID) emphasize the importance of cognitive appraisals in influencing parents' levels of stress and their adaptations to difficulties presented by the children. This study investigated the relationships between parental cognitions, child characteristics, family support and parenting stress. The aspects of cognitions studied were: parenting self-esteem (including efficacy and satisfaction) and parental locus of control.

METHODS

The group studied consisted of 46 mothers of children with ID. The Vineland Adaptive Behavior Scales and Maladaptive Behavior Domain were administered by interview. Mothers also completed four questionnaires: the Family Support Scale, the Parenting Sense of Competence Scale, a shortened form of the Parental Locus of Control Scale and the Parenting Stress Index (Short Form).

RESULTS

Data were analysed using Pearson's correlation coefficients, partial correlations and a regression analysis. The results indicated that most of the variance in parenting stress was explained by parental locus of control, parenting satisfaction and child behaviour difficulties. Whilst there was also a strong correlation between family support and parenting stress, this was mediated by parental locus of control.

CONCLUSIONS

The results demonstrate the potential importance of parental cognitions in influencing parental stress levels. It is argued that these results have implications for clinical interventions for promoting parents' coping strategies in managing children with ID and behavioural difficulties.

HIV protease inhibitors: synthesis and activity of N-aryl-N'-hydroxyalkyl hydrazide pseudopeptides

We describe the synthesis and activities of a series of pseudopeptides containing an N-aryl-N'-hydroxyalkyl hydrazide core structure to inhibit human immunodeficiency virus protease and viral replication. Of the series, compound Hmb-Leu-N(Bzl)-N(CH2-CH-OH)-rPro-Boc (24) displayed the greatest inhibitory potency (IC50 < 1 microM) and exhibited enzymatic resistance and stability in vitro.

Characterization and comparison of recombinant human and rat TRPV1 receptors: effects of exo- and endocannabinoids

BACKGROUND

TRPV1 is a ligand-gated ion channel whose activation by capsaicin increases intracellular Ca(2+) ([Ca(2+)](i)). TRPV1 and cannabinoid CB(1) receptor activation are capable of eliciting analgesia. In this study, using recombinant human (h) and rat (r) TRPV1 receptors expressed in HEK293 cells, we have performed a comparison of both TRPV1 species at 22 and 37 degrees C and compared endo- and exocannabinoid activity at both receptors.

METHODS

[Ca(2+)](i) was measured in Fura-2-loaded HEK293(hTRPV1) and HEK293(rTRPV1) cells. To assess native CB(1) receptor activity, [(35)S]GTPgammaS binding to membranes prepared from rat cerebellum was measured.

RESULTS

Both capsaicin (pEC(50) rat approximately 6.9 and pEC(50) human approximately 6.8 at 37 degrees C) and anandamide (pEC(50) rat approximately 5.3 and pEC(50) human approximately 5.8 at 37 degrees C) produced a concentration-dependent increase in [Ca(2+)](i) in rat and human systems and at 22 and 37 degrees C. In HEK293(rTRPV1) cells, anandamide appeared to be a partial agonist. Capsazepine demonstrated competitive antagonism at both human and rat TRPV1 receptors and at both temperatures studied. Capsazepine effects were not temperature dependent: pK(B) at rTRPV1 was 5.98 at 22 degrees C and 6.02 at 37 degrees C, and pK(B) at hTRPV1 was 6.76 at 22 degrees C and 6.75 at 37 degrees C. However, there was a consistent 6-fold increase in capsazepine potency for hTRPV1 relative to rTRPV1. The exocannabinoid Delta(9)-tetrahydrocannabinol failed to increase [Ca(2+)](i), although its solvent ethanol was an effective TRPV1 activator. In the [(35)S]GTPgammaS binding assay using rat cerebellar membranes, anandamide (pEC(50) approximately 5.8) and Delta(9)-tetrahydrocannabinol (pEC(50) approximately 7.1), but not capsaicin, stimulated binding. Delta(9)-tetrahydrocannabinol was a partial agonist. pEC(50) values for anandamide at rTRPV1 and rCB(1) were similar.

CONCLUSIONS

There were small differences in the pharmacology of rat and human TRPV1 receptors. Whilst capsaicin activated TRPV1 and Delta(9)-tetrahydrocannabinol activated CB(1), anandamide is an endogenous agonist for both receptor systems.

Quantification of tartrate resistant acid phosphatase distribution in mouse tibiae using image analysis

Tartrate resistant acid phosphatase (TRAP) activity of bone is a suitable biochemical marker for osteoclastic bone resorption. Qualitatively, the histochemical distribution of TRAP has been used to identify osteoclasts responsible for bone resorption; however, there have been few attempts to quantify TRAP localization. We describe a method for evaluating bone resorption by quantifying area percentages of positive TRAP localization using image analysis. Mouse tibiae were paraffin embedded following demineralization in disodium ethylenediamine tetraacetic acid. Longitudinal sections of tibia were cut from 15 levels in the left and the right limbs of six mice (180 sections total) and stained for TRAP distribution. Positive TRAP localization was quantified by pixel area count and reported as a percentage of the total tissue area specified. The 1.85 mm2 region of interest was placed at the midpoint of the epiphyseal growth plate containing the provisional calcification layer and the primary spongiosa, while excluding cortical bone of each mouse tibia. The percentage of TRAP localization ranged from 0.95 to 1.31% and was not significantly different from level to level or limb to limb in each mouse (p > 0.100). Within the same region of interest, an osteoclast count along the bone perimeter also was performed. We demonstrated a strong correlation (r2 = 0.903) between the conventional histomorphometric osteoclast index and positive TRAP localization, validating the latter as an alternative method to assess bone resorption. Quantitative analysis of TRAP is significant because it allows statistical comparisons between treatment groups, promotes precise pathological diagnoses and facilitates a reference data base that may aid the study of bone related diseases involving increased bone resorption.

Respiratory syncytial virus bronchiolitis in ex-preterm infants in the Scottish highlands: review of hospital admissions and an analysis of hospital cost

Ex-preterm infants are vulnerable to respiratory syncytial virus (RSV) bronchiolitis and their hospital admission is associated with increased morbidity. Palivizumab is currently available as prophylaxis against RSV infection but its use in ex-preterm infants is controversial. A retrospective case review study was, therefore, carried out to determine the rate of readmission with RSV bronchiolitis among ex-preterm infants in the Highland Region of Scotland and to estimate the hospital cost per admission. Between 1995 and 1999, a total of 3,046 children under 2 years of age were admitted to Raigmore Hospital, 1,691 of whom (60.4%) lived outwith Inverness. 507 children had acute bronchiolitis and ex preterm infants with RSV positive bronchiolitis accounted for 3.6% of total admissions with acute bronchiolitis. 72% of these children lived outwith Inverness. The median length of hospital stay for children born at less than 30 weeks and for children who had had bronchopulmonary dysplasia (BPD) was 6 and 10.5 days respectively. The average hospital costs per admission for children of less than 30 weeks and children of more than 30 weeks were 3,376 Pounds and 2,074 Pounds respectively. It was more expensive for children with BPD (4,431 Pounds per admission) when compared with those without BPD (1,959 Pounds per admission). This study has shown that most of the children admitted to hospital lived outwith Inverness, many at some considerable distance, and this, as much as severity of illness, may have contributed to hospital admission. Further studies are required to determine productivity losses associated with RSV infection and justification of use of Palivizumab in ex preterm infants of less than 30 weeks gestation and of BPD living in remote areas of Scottish Highlands.

Faith and health self-management of rural older adults

This analysis uses in-depth interview data collected from 145 African American, European American and Native American men and women aged 70 and older who reside in two rural North Carolina counties to understand the role of religious faith and prayer in the health self-management of these older adults. The analysis addresses three specific questions: how do these older adults use religion to help them manage their health; are there ethnic and gender differences in the use of religion; and are differences in health status related to differences in the use of religion? The integral role of religion in the lives of these older rural adults is an overarching theme present in the interview texts. Six major themes link religion and health self-management: (1) prayer and faith in health self-management, (2) reading the Bible, (3) church services, (4) mental and spiritual health, (5) stories of physical healing, and (6) ambivalence. Faith and religious activities provide an anchor in the lives of these older adults. There is little variation in the use of religion for health self-management by gender, ethnicity or health status. These results suggest that the strength of religion in rural culture may limit the effectiveness of general religiosity scales to discern the relationship of religion to health and health behavior in rural populations.

Pharmacological profile of the cyclic nociceptin/orphanin FQ analogues c[Cys10,14]N/OFQ(1-14)NH2 and c[Nphe1,Cys10,14]N/OFQ(1-14)NH2

In this study we describe the activity of two cyclic nociceptin/orphanin FQ (N/OFQ) peptides; c[Cys(10,14)]N/OFQ(1-14)NH(2) (c[Cys(10,14)]) and its [Nphe(1)] derivative c[Nphe(1),Cys(10,14)]N/OFQ(1-14)NH(2) (c[Nphe(1),Cys(10,14)]) in native rat and mouse and recombinant human N/OFQ receptors (NOP). Cyclisation may protect the peptide from metabolic degradation. In competition binding studies of rat, mouse and human NOP the following rank order pK(i) was obtained: N/OFQ(1-13)NH(2)(reference agonist)>N/OFQ=c[Cys(10,14)]>>c[Nphe(1)Cys(10,14)]. In GTPgamma(35)S studies of Chinese hamster ovary cells expressing human NOP (CHO(hNOP)) c[Cys(10,14)] (pEC(50) 8.29) and N/OFQ(1-13)NH(2) (pEC(50) 8.57) were full agonists whilst c[Nphe(1)Cys(10,14)] alone was inactive. Following 30 min pre-incubation c[Nphe(1)Cys(10,14)] competitively antagonised the effects of N/OFQ(1-13)NH(2) with a pA(2) and slope factor of 6.92 and 1.01 respectively. In cAMP assays c[Cys(10,14)] (pEC(50) 9.29, E(max) 102% inhibition of the forskolin stimulated response), N/OFQ(1-13)NH(2) (pEC(50) 10.16, E(max) 103% inhibition) and c[Nphe(1)Cys(10,14)] (~80% inhibition at 10 microM) displayed agonist activity. In the mouse vas deferens c[Cys(10,14)] (pEC(50) 6.82, E(max) 89% inhibition of electrically evoked contractions) and N/OFQ(1-13)NH(2) (pEC(50) 7.47, E(max) 93% inhibition) were full agonists whilst c[Nphe(1)Cys(10,14)] alone was inactive. c[Nphe(1)Cys(10,14)] (10 microM) competitively antagonised the effects of N/OFQ(1-13)NH(2) with a pK(B) of 5.66. In a crude attempt to assess metabolic stability, c[Cys(10,14)] was incubated with rat brain membranes and then the supernatant assayed for remaining peptide. Following 60 min incubation 64% of the 1 nM added peptide was metabolised (compared with 54% for N/OFQ-NH(2)). In summary, we report that c[Cys(10,14)] is a full agonist with a small reduction in potency but no improvement in stability whilst c[Nphe(1)Cys(10,14)] displays tissue (antagonist in the vas deferens) and assay (antagonist in the GTPgamma(35)S assay and agonist in cAMP assay) dependent activity.

Partial agonist behaviour depends upon the level of nociceptin/orphanin FQ receptor expression: studies using the ecdysone-inducible mammalian expression system

(1) Partial agonism is primarily dependent upon receptor density and coupling efficiency. As these parameters are tissue/model dependent, intrinsic activity in different tissues can vary. We have utilised the ecdysone-inducible expression system containing the human nociceptin/orphanin FQ (N/OFQ) peptide receptor (hNOP) expressed in Chinese hamster ovary cells (CHOINDhNOP) to examine the activity of a range of partial agonists in receptor binding, GTPgamma35S binding and inhibition of adenylyl cyclase studies. (2) Incubation of CHOINDhNOP cells with ponasterone A (PON) induced hNOP expression ([leucyl-3H]N/OFQ binding) of 24, 68, 191 and 1101 fmol mg-1 protein at 1, 2, 5 and 10 microm PON, respectively. At 191 fmol mg-1, protein hNOP pharmacology was identical to that reported for other traditional expression systems. (3) pEC50 values for GTPgamma35S binding ranged from 7.23 to 7.72 (2-10 microm PON) for the partial agonist [Phe1psi(CH2-NH)Gly2]N/OFQ(1-13)-NH2 ([F/G]N/OFQ(1-13)-NH2) and 8.12-8.60 (1-10 microm PON) for N/OFQ(1-13)-NH2 and Emax values (stimulation factor relative to basal) ranged from 1.51 to 3.21 (2-10 microm PON) for [F/G]N/OFQ(1-13)-NH2 and 1.28-6.95 (1-10 microm) for N/OFQ(1-13)-NH2. Intrinsic activity of [F/G]N/OFQ(1-13)-NH2 relative to N/OFQ(1-13)-NH2 was 0.3-0.5. [F/G]N/OFQ(1-13)-NH2 did not stimulate GTPgamma35S binding at 1 microm PON, but competitively antagonised the effects of N/OFQ(1-13)-NH2 with a pKB=7.62. (4) pEC50 values for cAMP inhibition ranged from 8.26 to 8.32 (2-10 microm PON) for [F/G]N/OFQ(1-13)-NH2 and 9.42-10.35 for N/OFQ(1-13)-NH2 and Emax values (% inhibition) ranged from 19.6 to 83.2 for [F/G]N/OFQ(1-13)-NH2 and 40.9-86.0 for N/OFQ(1-13)-NH2. The intrinsic activity of [F/G]N/OFQ(1-13)-NH2 relative to N/OFQ(1-13)-NH2 was 0.48-0.97. (5) In the same cellular environment with receptor density as the only variable, we show that the profile of [F/G]N/OFQ(1-13)-NH2 can be manipulated to encompass full and partial agonism along with antagonism.

Assessment of the activity of a novel nociceptin/orphanin FQ analogue at recombinant human nociceptin/orphanin FQ receptors expressed in Chinese hamster ovary cells

The neuropeptide nociceptin/orphanin FQ (N/OFQ) is the endogenous ligand for the nociceptin receptor (NOP). In an attempt to identify high potency NOP agonists for use in the brain we have compared the activity of a novel N/OFQ analogue [Phe(1)Psi(CH(2)-O)Gly(2)]N/OFQ(1-13)NH(2) ([F/G-O]) with the existing [Phe(1)Psi(CH(2)-NH)Gly(2)]N/OFQ(1-13)NH(2) ([F/G]). Both peptides are modified between the first two N-terminal amino acids and are further compared with the agonist template N/OFQ(1-13)NH(2) in [(3)H]N/OFQ binding, GTPgamma[(35)S] binding and cAMP inhibition studies using Chinese hamster ovary cells expressing the recombinant human NOP. All peptides displaced [(3)H]N/OFQ, stimulated GTPgamma[(35)S] binding and inhibited cAMP formation. In [(3)H]N/OFQ binding and GTPgamma[(35)S] binding the rank order affinity and potency was N/OFQ(1-13)NH(2)>[F/G-O]>[F/G]. In GTPgamma[(35)S] binding [F/G] was a clear partial agonist with intrinsic activity (E(max) stimulation factor, mean+/-SEM, n=4) of 7.75+/-1.02 compared with N/OFQ(1-13)NH(2) of 11.13+/-1.76. The efficacy of [F/G-O] (10.17+/-1.88) approached that of the full agonist N/OFQ(1-13)NH(2). Downstream, at the level of cAMP formation, all peptides were full agonists with the following rank order potency: N/OFQ(1-13)NH(2)>[F/G-O]=[F/G]. The enhanced potency and intrinsic activity of the novel [F/G-O] modification makes this an interesting peptide for further in vivo analysis.

Visceral manifestations in hereditary haemorrhagic telangiectasia type 2

Hereditary haemorrhagic telangiectasia (HHT) is a genetic vascular disorder characterised by epistaxis, telangiectases, and visceral manifestations. The two known disease types, HHT1 and HHT2, are caused by mutations in the endoglin (ENG) and ALK-1 genes, respectively. A higher frequency of pulmonary arteriovenous malformations (AVMs) has been reported for HHT1 while HHT2 is thought to be associated with a lower penetrance and milder disease manifestations. In this study, we present 10 families with an ALK-1 genotype. Visceral manifestations were detected in 24 (26%) of the 93 HHT2 patients from nine of the families and included gastrointestinal bleeding (14%), intrahepatic shunts (6%), and AVMs in the lung (4%) and brain (3%). Gastrointestinal bleeding, the most frequent visceral manifestation, was reported in six of the 10 families, mostly in patients over the age of 50. These patients also had frequent epistaxis and suffered from anaemia, often requiring blood transfusions. The identification of ALK-1 mutations in subjects with a suspected diagnosis and without clinical signs of HHT argue in favour of a molecular diagnosis. We also analysed the data published on 44 families with HHT2 and conclude that visceral manifestations occur in 26 of these families and affect 30% of HHT2 patients. This is considered an underestimate given incomplete and variable screening for lung, brain, and/or liver involvement in different clinical centres. These findings, however, stress the need for an early diagnosis of HHT that can be useful for the early control of associated visceral involvement.

Induction interferon and ribavirin for re-treatment of chronic hepatitis C patients unresponsive to interferon alone

BACKGROUND

The optimal treatment for hepatitis C patients unresponsive to interferon is unclear. High-dose induction interferon may enhance early viral clearance, whilst ribavirin reduces relapse; in combination, they may improve sustained virological response rates.

AIM

To compare the efficacy and safety of re-treatment with interferon induction, with or without ribavirin, in interferon non-responders.

METHODS

We randomized 218 biochemical interferon non-responders to 10 MU interferon alpha 2b daily for 4 weeks, followed by 5 MU thrice weekly for 48 weeks plus ribavirin (II + R), or to the same interferon regimen plus placebo (II + P). All patients were viraemic at entry.

RESULTS

The sustained virological response in the II + R group was 39%[95% confidence interval (CI), 30-48%], compared with 16% (95% CI, 9-23%) in the II + P group (P < 0.002). The study drug was discontinued for intolerable symptoms during induction in 9% of the II + R group and in 5% of the II + P group. By logistic regression, a sustained virological response was more likely following II + R treatment (odds ratio, 4.4; 95% CI, 2.1-9.7) and less likely in patients with genotype 1 or 4 (odds ratio, 0.16; 95% CI, 0.07-0.36).

CONCLUSION

High-dose induction interferon plus ribavirin is well tolerated and effective for patients unresponsive to interferon alone.

UFP-101, a high affinity antagonist for the nociceptin/orphanin FQ receptor: radioligand and GTPgamma(35)S binding studies

Studies of the pharmacology of nociceptin/orphanin FQ (N/OFQ) and its receptor (NOP) have been hampered by the lack of a range of high potency antagonists. In this study we have examined the effects of a novel N/OFQ analogue [Nphe(1),Arg(14),Lys(15)]N/OFQ NH(2) hereafter referred to as UFP-101. [(3)H]N/OFQ competition binding and GTPgamma(35)S binding assays were performed using CHO cells expressing the human NOP receptor (CHO(hNOP)). UFP-101 (pK(i) of 10.14+/-0.09) and a range of NOP selective agonists displaced [(3)H]N/OFQ binding with the following rank order of affinity: [Arg(14),Lys(15)]N/OFQ>[( pF)Phe(4)]N/OFQ(1-13)NH(2)>N/OFQ(1-13)NH(2)>UFP-101>N/OFQ>Ro64-6198>[Nphe(1)]N/OFQ(1-13)NH(2). N/OFQ, N/OFQ(1-13)NH(2), [( pF)Phe(4)]N/OFQ(1-13)NH(2), [Arg(14),Lys(15)]N/OFQ and Ro64-6198 also produced a concentration dependent (pEC(50) values of 8.75+/-0.11, 9.28+/-0.15, 9.69+/-0.04, 9.12+/-0.11 and 8.09+/-0.07 respectively) and saturable stimulation of GTPgamma(35)S binding and all were full agonists. UFP-101 did not stimulate GTPgamma(35)S binding per se, but produced a concentration dependent and parallel rightward shift in the concentration response curves to all agonists. UFP-101 yielded pA(2) values in the range 8.4-9.0. For comparison a pA(2) for [Nphe(1)]N/OFQ(1-13)NH(2) (the template for UFP-101) against N/OFQ of 7.33+/-0.08 was obtained. Slope factors for the Schild regression lines were approximately 1 indicating competitivity. When UFP-101 is compared with its template molecule [Nphe(1)]N/OFQ(1-13)NH(2), Arg(14),Lys(15) substitution produced approximately 1 log greater potency. We suggest that due to its high potency UFP-101 should prove a further useful tool in the evaluation of the N/OFQ-NOP receptor system.

Search for nu(mu)-->nu(e) and nu(mu)-->nu(e) oscillations at NuTeV

Limits on nu(mu)-->nu(e) and nu(mu)-->nu(e) oscillations are extracted using the NuTeV detector with sign-selected nu(mu) and nu(mu) beams. In nu(mu) mode, for the case of sin(2)2alpha = 1, Delta(m)(2)>2.6 eV(2) is excluded, and for Delta(m)(2)>>1000 eV(2), sin(2)2alpha>1.1 x 10(-3). The NuTeV data exclude the high Delta(m)(2) end of nu(mu)-->nu(e) oscillation parameters favored by the LSND experiment without the need to assume that the oscillation parameters for nu and nu are the same. We present the most stringent experimental limits for nu(mu)(nu(mu))-->nu(e)(nu(e)) oscillations in the large Delta(m)(2) region.

End-stage renal disease in liver transplants

Renal dysfunction is one of the most significant problems following orthotopic liver transplantation (OLTx). Since the major risk factor for delayed renal dysfunction following OLTx is presumed to be cyclosporine (CsA) nephrotoxicity, it has been suggested that CsA is the most probably cause of end-stage renal disease (ESRD) in this population of patients. To test this hypothesis the records of OLTx patients in our center who developed ESRD requiring dialysis were reviewed. There were 132 consecutive adult patients with end-stage liver disease (ESLD) who received 146 OLTxs between 1990 and 2000. Five patients (3.4%) developed ESRD requiring dialysis. Four of the five patients developed nephrotic range proteinuria prior to reaching ESRD. Renal biopsy in four patients showed focal segmental glomerulosclerosis, diabetic nephropathy, membranous nephropathy and cyclosporine toxicity. The underlying hepatic and metabolic disease may have played a role in the genesis of glomerular diseases in these OLTx patients. Perhaps if more renal biopsies are performed in OLTx patients with chronic renal failure, we might discover that, although CsA/tacrolimus therapy is a definite risk factor for post-transplantation chronic renal failure, other disease processes may also play a significant role.

Direct search for charged higgs bosons in decays of top quarks

We present a search for charged Higgs bosons in decays of pair-produced top quarks in pp collisions at sqrt[s] = 1.8 TeV recorded by the D0 detector at the Fermilab Tevatron collider. With no evidence for signal, we exclude most regions of the ( M(H+/-),tan(beta)) parameter space where the decay t--> H(+)b has a branching fraction >0.36 and B(H+/--->tau(nu)(tau)) is large.

Precise determination of electroweak parameters in neutrino-nucleon scattering

The NuTeV Collaboration has extracted the electroweak parameter sin(2)theta(W) from the measurement of the ratios of neutral current to charged current nu and (-)nu cross sections. Our value, sin(2)theta((on-shell))(W) = 0.2277 +/- 0.0013(stat) +/- 0.0009(syst), is 3 standard deviations above the standard model prediction. We also present a model independent analysis of the same data in terms of neutral-current quark couplings.

Evidence-based health care and community nursing: issues and challenges

This paper examines the implications of the movement towards evidence-based health care for community-based, primary health care nursing in Australia. While both aim to improve health status, we argue that they are antithetical in many respects. Community nurse practitioners draw upon primary health care principles and adopt a holistic, preventive, empowering approach to working with and in communities. By contrast, evidence-based approaches utilise systematic reviews of primarily quantitative research to inform decisions about health at three levels: public health, the health care system, and individual patients. In response to this challenge, community nurses must reiterate their philosophies and practice models. Moreover, it is imperative to produce verifiable evidence of the effectiveness of their approach while mounting a thorough critique of the evidence-based movement.

Office design and technology placement: fundamental foundations

Build technology infrastructure on a solid foundation. Outline the technology vision, determine the budget, research products and vendors, plan a practical installation and support your investment with training. Reap the rewards of today's dental technologies by establishing your practice as high technology yet soft touch.

Morphologic features of the rheumatic mitral regurgitant valve by three-dimensional echocardiography

BACKGROUND

Rheumatic fever remains a significant worldwide cause of mitral regurgitation (MR). We describe morphologic features of the rheumatic MR valve by quantitative 3-dimensional (3D) echocardiography.

METHODS

Eight healthy subjects and 16 patients with less than moderate (n = 7) or more than or equal to moderate (n = 9) rheumatic MR underwent 3D echocardiography by use of freehand transthoracic scanning. Left ventricular (LV) borders, mitral chordae, papillary muscles and annuli were traced at end-diastole (ED) and end-systole (ES) with LV surfaces and mitral annulus reconstructed in 3D. Regional LV function was quantified by myocardial thickening. Regional LV shape was assessed by alignment of diseased ED endocardial surfaces to a reference normal surface.

RESULTS

In the diseased group, LVs were more spheric and had regional shape abnormality in the area of anterior papillary muscle attachment. LV volumes, ejection fraction, and regional function in the areas of papillary attachment were not different. Mitral annular length and area were increased and correlated with LVED volume but were no different in height, sphericity, or beat-to-beat deformity. Chordal and papillary muscle lengths were not reduced. The interchordal angle (between the anterior and posterior chordae) was more acute in MR.

CONCLUSION

Alterations in LV geometry and mitral apparatus morphologic features contribute to rheumatic regurgitant disease. Consequent changes include malalignment of the papillary muscles and a narrowed interchordal angle that is opposite to the widening seen in MR from dilated cardiomyopathy. We hypothesize that leaflet involvement with retraction causes increased tension on the chordae, a reduction in the interchordal angle, and a consequent coaptation defect.