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Anderson JR, Harrington D. Re: The management of interim analyses in drug development by Karen M. Facey and John A. Lewis, Statistics in Medicine, 17, 1801-1809 (1998). Stat Med 1999; 18:2063-5. [PMID: 10440887 DOI: 10.1002/(sici)1097-0258(19990815)18:15<2063::aid-sim189>3.0.co;2-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Fenelon M, Ryan M, Rea M, Guinee T, Ross R, Hill C, Harrington D. Elevated Temperature Ripening of Reduced Fat Cheddar Made with or Without Lacticin 3147-Producing Starter Culture. J Dairy Sci 1999. [DOI: 10.3168/jds.s0022-0302(99)75203-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Lawless F, Murphy JJ, Harrington D, Devery R, Stanton C. Elevation of conjugated cis-9, trans-11-octadecadienoic acid in bovine milk because of dietary supplementation. J Dairy Sci 1998; 81:3259-67. [PMID: 9891271 DOI: 10.3168/jds.s0022-0302(98)75890-4] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cows on pasture were fed full fat soybeans (toasted, flaked, and pelleted) or ground full fat rapeseeds to investigate effects on cis-9, trans-11-octadecadienoic acid in milk. Three herds of 16 cows each that were on pasture were fed 3.1 kg/d of unmolassed beet pulp (control), 3.0 kg/d of rapeseed concentrate, or 3.1 kg/d of a soybean supplement. The concentration of cis-9, trans-11-octadecadienoic acid in the milk of cows fed the rapeseed and soybean supplements was significantly higher than in the milk of cows fed the control diet during the feeding trial. Over the trial, the cis-9, trans-11-octadecadienoic acid concentration in the milk of individual cows varied from 6.8 to 25.7 mg/g of fat in the control herd, from 10.6 to 33.5 mg/g of fat in the herd fed the rapeseed concentrate, and from 8.8 to 30.5 mg/g of fat in the herd fed the soybean supplement. The concentration of cis-9, cis-12-octadecadienoic acid, the substrate for cis-9, trans-11-octadecadienoic acid synthesis in the rumen, was 4.9 g/100 g of fatty acid methyl esters in the milk fat of cows fed the soybean supplement, 2.5 g/100 g of fatty acid methyl esters in the milk fat of cows fed the rapeseed concentrate, and 2.3 g/100 g of fatty acid methyl esters in the milk fat of the control cows. Milk yield and milk constituent yields were not affected by supplementation of either full fat soybeans or rapeseeds compared with controls, but milk protein concentration was significantly reduced by both oilseed supplements.
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Turner LF, Kaddoura S, Harrington D, Cooper JM, Poole-Wilson PA, Schapira AH. Mitochondrial DNA in idiopathic cardiomyopathy. Eur Heart J 1998; 19:1725-9. [PMID: 9857927 DOI: 10.1053/euhj.1998.1125] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIMS To investigate the frequency of pathogenic mitochondrial DNA mutations in idiopathic cardiomyopathy. METHODS AND RESULTS We investigated the occurrence of seven previously reported pathogenic mitochondrial DNA point mutations in 52 patients with idiopathic dilated cardiomyopathy (blood n=33, myocardium n=19), 10 patients with hypertrophic cardiomyopathy (blood n=7, myocardium n=3), 67 controls with ischaemic heart disease (blood n=53, myocardium n=14) and eight controls with no overt cardiac disease (blood n=4, myocardium n=4). Total DNA or cell lysates were studied by polymerase chain reaction amplification and restriction fragment length polymorphism analysis for the identification of the following mitochondrial DNA point mutations: A3243G, A3252G, A3260G, A4269G, A8344G, T8993G/C and T9997C. None of these point mutations were detected in the blood or myocardium of any of the individuals with dilated or hypertrophic cardiomyopathy or in the controls. In addition we investigated the occurrence of major deletions of mitochondrial DNA in eight patients with dilated cardiomyopathy (myocardium n=7, skeletal muscle n=1), three patients with ischaemic heart disease (myocardium n=3) and one control myocardium by Southern blot analysis. Deletions were not detected in any of the patients. CONCLUSION The results suggest that although these mutations are known to be associated with specific cardiomyopathies, they are not a common feature of idiopathic cardiomyopathy.
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Rewerts JM, McCaw DL, Cohn LA, Wagner-Mann C, Harrington D. Recombinant human granulocyte colony-stimulating factor for treatment of puppies with neutropenia secondary to canine parvovirus infection. J Am Vet Med Assoc 1998; 213:991-2. [PMID: 9776994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVE To determine the effect of treatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF) for puppies with neutropenia secondary to canine parvovirus infection. DESIGN Randomized controlled clinical trial. ANIMALS 23 puppies. PROCEDURE Diagnosis was confirmed by use of an ELISA for detection of canine parvovirus antigen in feces, and all puppies received standard treatment for parvoviral enteritis. All puppies had neutropenia (< 1,000 neutrophils/microliter) at the time of admission to the hospital or within 4 days afterward. Eleven puppies were treated with rhG-CSF daily until neutrophil count was > 1,500 cells/microliter; the remaining 12 puppies were not treated with rhG-CSF. RESULTS We did not detect any significant differences between groups regarding duration of hospitalization, neutrophil count when neutropenia was first detected, lowest neutrophil count, or time until neutrophil count was > 1,500 cells/microliter. CLINICAL IMPLICATIONS Results suggest that treatment with rhG-CSF may not be beneficial in puppies with neutropenia secondary to canine parvovirus infection.
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Liang Z, Ye J, Cheng J, Li J, Harrington D. Quantitative cardiac SPECT in three dimensions: validation by experimental phantom studies. Phys Med Biol 1998; 43:905-20. [PMID: 9572514 DOI: 10.1088/0031-9155/43/4/018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A mathematical framework for quantitative SPECT (single photon emission computed tomography) reconstruction of the heart is presented. An efficient simultaneous compensation approach to the reconstruction task is described. The implementation of the approach on a digital computer is delineated. The approach was validated by experimental data acquired from chest phantoms. The phantoms consisted of a cylindrical elliptical tank of Plexiglass, a cardiac insert made of Plexiglass, a spine insert of packed bone meal and lung inserts made of styrofoam beads alone. Water bags were added to simulate different body characteristics. Comparison between the quantitative reconstruction and the conventional FBP (filtered backprojection) method was performed. The FBP reconstruction had a poor quantitative accuracy and varied for different body configurations. Significant improvement in reconstruction accuracy by the quantitative approach was demonstrated with a moderate computing time on a currently available desktop computer. Furthermore, the quantitative reconstruction was robust for different body characteristics. Therefore, the quantitative approach has the potential for clinical use.
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Alvarez FJ, Pearson JC, Harrington D, Dewey D, Torbeck L, Fyffe RE. Distribution of 5-hydroxytryptamine-immunoreactive boutons on alpha-motoneurons in the lumbar spinal cord of adult cats. J Comp Neurol 1998; 393:69-83. [PMID: 9520102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent studies have shown that at least some of the functional effects of serotonin (5-HT) on motoneuron excitability are direct and are mediated via postsynaptic 5-HT receptors on motoneurons. To determine the spatial distribution of direct inputs from the serotonin system on the proximal and distal dendrites of individual motoneurons, we examined identified motoneurons in vivo with a combination of immunohistochemical localization of 5-HT-immunoreactive boutons and intracellular staining with horseradish peroxidase. Seventeen intracellularly stained motoneurons from 12 adult cats were analyzed with light microscopy. Quantitative analysis of 5-HT boutons apposed to dendrites of five representative motoneurons that were entirely reconstructed in three dimensions (each from the lumbosacral spinal cord of a different animal) revealed a total of 7,848 contacts (1,570+/-487 contacts/postsynaptic neuron; mean +/- SD) over the dendrites of these cells. Analysis of contacts on the soma of two of these cells, and on the somas of an additional 12 intracellularly stained motoneurons, revealed a wide range of somatic contacts (11-211 contacts/cell) on motoneuron cell bodies, with an average of 52 contacts/cell. These results indicate that the vast majority of 5-HT-immunoreactive boutons are apposed to dendritic branches rather than to the somatic surface of motoneurons. The spatial distribution of contacts essentially matched the distribution of surface membrane area of the postsynaptic neuron, resulting in a relatively uniform density of contacts (<1/100 microm2) on proximal and distal dendrites. Consequently, the frequency of contacts was higher on the proximal dendritic compartments where available membrane area is greater. There was no preferential distribution of contacts to particular dendrites. Light/electron microscopic correlations were performed on 21 boutons that contacted dendrites (n = 7) of three motoneurons from different animals. At the electron microscope level, most appositions (18/21; 85.7%) selected by our light microscopic criteria were confirmed as direct contacts when the 5-HT boutons were examined through serial sections. Synaptic junctions, generally small and symmetric, were positively identified in only a subset of these cases (n = 6; 28.6%), in part due to the obscuring effects of the peroxidase histochemical precipitate present in both pre- and postsynaptic profiles. A few 5-HT boutons (3/21; 14.3%) selected as contacts by our light microscopic criteria were in fact separated from the adjacent labeled dendrites; in two of these three cases, the separation was due to intrusion of very thin glial lamellae (<0.3 microm in cross section). These results indicate that the bulbospinal serotonergic system(s) provide a significant, direct synaptic input to spinal motoneurons that innervate hindlimb muscles. The nature of the modulatory actions exerted by such widespread synaptic inputs will affect all regions of the somatodendritic membrane and will ultimately depend on the nature of the 5-HT receptors present over different parts of the postsynaptic neuron's dendritic tree.
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Alvarez F, Pearson J, Harrington D, Dewey D, Torbeck L, Fyffe R. Distribution of 5-hydroxytryptamine-immunoreactive boutons on ?-motoneurons in the lumbar spinal cord of adult cats. J Comp Neurol 1998. [DOI: 10.1002/(sici)1096-9861(19980330)393:1<69::aid-cne7>3.0.co;2-o] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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84
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Guinee TP, Mulholland EO, Mullins C, Corcoran MO, Connolly JF, Beresford T, Mehra R, O'Brien BJ, Murphy JJ, Stakelum G, Harrington D. Effect of altering the daily herbage allowance to cows in mid lactation on the composition, ripening and functionality of low-moisture, part-skim Mozzarella cheese. J DAIRY RES 1998; 65:23-30. [PMID: 9513053 DOI: 10.1017/s0022029997002665] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Milk was collected from three spring-calving herds, on different daily herbage allowances (DHA) of perennial rye-grass (16, 20 or 24 kg dry matter (DM)/cow for a 17 week period. On five occasions, at weekly intervals in the middle of the period, the three different milks were converted into low-moisture part-skim Mozzarella cheese. Increasing the DHA resulted in significant increases in the concentrations of protein in the cheesemilk (P < 0.05) and cheese whey (P < 0.02). The moisture-adjusted cheese yield increased significantly (P < 0.01) on raising the DHA from 16 to 24 kg grass DM/cow. DHA had no significant effects on any of the gross compositional values of the cheese (although moisture and fat-in-DM levels tended to decrease and increase respectively with increasing DHA). The hardness of the uncooked cheese and functionality of cooked cheese (i.e. melt time, flowability, stretch and viscosity) were not significantly influenced by DHA over the 115 d ripening period at 4 degrees C.
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Harrington D. Similarities Between Exercise Capacity and Ventilation in Patients With Mitochondrial Myopathy and Chronic Heart Failure. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(97)85155-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Harrington D, Black MM, Starr RH, Dubowitz H. Child neglect: relation to child temperament and family context. THE AMERICAN JOURNAL OF ORTHOPSYCHIATRY 1998; 68:108-116. [PMID: 9494647 DOI: 10.1037/h0080275] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Relationships among neglect and child and family characteristics were examined in a sample of 121 urban, low-income families with a child under 30 months. Maternal reports of more difficult child temperament predicted emotional neglect; family context was indirectly related, as mothers in well functioning families with more support reported their children as being less difficult. Neither child temperament nor family context was related to physical neglect.
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Harrington D, Chambers J, Anker S, Morgan-Hughes J, Poole-Wilson P, Coats A. Similarities between exercise capacity and ventilation in patients with mitochondrial myopathy and chronic heart failure. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(98)82087-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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88
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Glick JH, Young ML, Harrington D, Schilsky RL, Beck T, Neiman R, Fisher RI, Peterson BA, Oken MM. MOPP/ABV hybrid chemotherapy for advanced Hodgkin's disease significantly improves failure-free and overall survival: the 8-year results of the intergroup trial. J Clin Oncol 1998; 16:19-26. [PMID: 9440718 DOI: 10.1200/jco.1998.16.1.19] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE To compare the efficacy of sequential mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) followed by doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) versus the MOPP/ABV hybrid regimen in advanced-stage Hodgkin's disease. PATIENTS AND METHODS A total of 737 patients with previously untreated stages III2A, IIIB, IVA, or IVB Hodgkin's disease and patients in first relapse after radiotherapy were prospectively randomized to sequential MOPP-ABV or MOPP/ABV hybrid. Of 691 eligible patients, 344 received the sequential regimen and 347 received the hybrid. RESULTS The overall response rate was 95%, with complete responses (CRs) in 79%: 83% on the MOPP/ABV hybrid and 75% on the sequential MOPP-ABVD arm (P = .02). With a median follow-up time of 7.3 years, the 8-year failure-free survival (FFS) rates were 64% for MOPP/ABV hybrid and 54% far sequential MOPP-ABVD (P = .01; 0.69 relative risk of failure, comparing MOPP/ABV hybrid v MOPP-ABVD). The 8-year overall survival rate was significantly better for the MOPP/ABV hybrid (79%) as compared with sequential MOPP-ABVD (71%) (P = .02; relative risk, 0.65). MOPP/ABV hybrid had significantly more life-threatening or fatal neutropenia and pulmonary toxicity than the sequential MOPP-ABVD arm, which was associated with significantly greater thrombocytopenia. Nine cases of acute myelogenous leukemia or myelodysplasia were reported on the sequential regimen as compared with only one on the hybrid (P = .01). CONCLUSION MOPP/ABV hybrid chemotherapy was significantly more effective than sequential MOPP-ABVD. FFS and overall survival were significantly improved on the hybrid arm, which was also associated with a lower incidence of acute leukemia or myelodysplasia.
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Clark AL, Harrington D, Chua TP, Coats AJ. Exercise capacity in chronic heart failure is related to the aetiology of heart disease. Heart 1997; 78:569-71. [PMID: 9470872 PMCID: PMC1892326 DOI: 10.1136/hrt.78.6.569] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE To assess whether the underlying aetiology of chronic heart failure is a predictor of exercise performance. SETTING Tertiary referral centre for cardiology. PATIENTS AND OUTCOME MEASURES Retrospective study of maximum exercise testing with metabolic gas exchange measurements in 212 patients with chronic heart failure who had undergone coronary angiography. Echocardiography and radionucleide ventriculography were used to determine indices of left ventricular function, and coronary arteriography was used to determine whether the cause of chronic heart failure was ischaemic heart disease (n = 122) or dilated cardiomyopathy (n = 90). RESULTS The cardiomyopathy group was younger (mean (SD) age 58.45 (11.66) years v 61.49 (7.42); p = 0.02) but there was no difference between the groups in ejection fraction or fractional shortening. Peak oxygen consumption (VO2) was higher in the dilated group, while the slope relating carbon dioxide production and ventilation (VE/VCO2 slope) was the same in both groups. Both groups achieved similar respiratory exchange ratios at peak exercise, suggesting that there was near maximum exertion. There was a relation between peak VO2 and age (peak VO2 = 33.9-0.267*age; r = 0.36; p < 0.001). After correcting for age, the peak achieved VO2 was still greater in the cardiomyopathy group than in the ischaemic group (p < 0.002). CONCLUSIONS Exercise performance for a given level of cardiac dysfunction appears to vary with the aetiology of heart failure. Thus the two diagnostic categories should be considered separately in relation to abnormalities of exercise physiology. The difference may in part account for the worse prognosis in ischaemic patients.
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Harrington D, Anker SD, Chua TP, Webb-Peploe KM, Ponikowski PP, Poole-Wilson PA, Coats AJ. Skeletal muscle function and its relation to exercise tolerance in chronic heart failure. J Am Coll Cardiol 1997; 30:1758-64. [PMID: 9385904 DOI: 10.1016/s0735-1097(97)00381-1] [Citation(s) in RCA: 269] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES This study sought to define the relation between muscle function and bulk in chronic heart failure (HF) and to explore the association between muscle function and bulk and exercise capacity. BACKGROUND Skeletal muscle abnormalities have been postulated as determinants of exercise capacity in chronic HF. Previously, muscle function in chronic HF has been evaluated in relatively small numbers of patients and with variable results, with little account being taken of the effects of muscle wasting. METHODS One hundred male patients with chronic HF and 31 healthy male control subjects were studied. They were matched for age (59.0 +/- 1.0 vs. 58.7 +/- 1.7 years [mean +/- SEM]) and body mass index (26.6 +/- 0.4 vs. 26.3 +/- 0.7 kg/m2). We assessed maximal treadmill oxygen consumption (VO2), quadriceps maximal isometric strength, fatigue (20-min protocol, expressed in baseline maximal strength) and computed tomographic cross-sectional area (CSA) at midthigh. RESULTS Peak VO2 was lower in patients (18.0 +/- 0.6 vs. 33.3 +/- 1.4 ml/min per kg, p < 0.0001), although both groups achieved a similar respiratory exchange ratio at peak exercise (1.15 +/- 0.01 vs. 1.19 +/- 0.03, p = 0.13). Quadriceps (582 vs. 652 cm2, p < 0.05) and total leg muscle CSA (1,153 vs. 1,304 cm2, p < 0.005) were lower in patients with chronic HF. Patients were weaker than control subjects (357 +/- 12 vs. 434 +/- 18 N, p < 0.005) and also exhibited greater fatigue at 20 min (79.1% vs. 92.1% of baseline value, p < 0.0001). After correcting strength for quadriceps CSA, significant differences persisted (5.9 +/- 0.2 vs. 7.0 +/- 0.3 N/cm2, p < 0.005), indicating reduced strength per unit muscle. In patients, but not control subjects, muscle CSA significantly correlated with peak absolute VO2 (R = 0.66, p < 0.0001) and is an independent predictor of peak absolute VO2. CONCLUSIONS Patients with chronic HF have reduced quadriceps maximal isometric strength. This weakness occurs as a result of both quantitative and qualitative abnormalities of the muscle. With increasing exercise limitation there is increasing muscle weakness. This progressive weakness occurs predominantly as a result of loss of quadriceps bulk. In patients, this muscular atrophy becomes a major determinant of exercise capacity.
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Harrington D, Coats AJ. Skeletal muscle abnormalities and evidence for their role in symptom generation in chronic heart failure. Eur Heart J 1997; 18:1865-72. [PMID: 9447313 DOI: 10.1093/oxfordjournals.eurheartj.a015194] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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92
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Ponikowski P, Chua TP, Piepoli M, Ondusova D, Webb-Peploe K, Harrington D, Anker SD, Volterrani M, Colombo R, Mazzuero G, Giordano A, Coats AJ. Augmented peripheral chemosensitivity as a potential input to baroreflex impairment and autonomic imbalance in chronic heart failure. Circulation 1997; 96:2586-94. [PMID: 9355898 DOI: 10.1161/01.cir.96.8.2586] [Citation(s) in RCA: 181] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The precise mechanisms responsible for the sympathetic overactivity and blunted baroreflex control in chronic heart failure (CHF) remain obscure. Augmented peripheral chemosensitivity has recently been demonstrated in CHF. We evaluated the relation between peripheral chemoreflex sensitivity and autonomic activity in patients with CHF. METHODS AND RESULTS We studied in 26 stable patients with CHF the peripheral chemosensitivity (ventilatory response to hypoxia using transient inhalations of pure nitrogen), autonomic balance (spectral analysis of heart rate variability [HRV]), and baroreflex sensitivity (bolus phenylephrine method and alpha index). To determine whether transient inactivation of peripheral chemoreceptors might influence autonomic balance, 12 patients underwent a second study during which they breathed 100% O2. Peripheral chemosensitivity correlated inversely with HRV power within the low-frequency band (0.04 to 0.15 Hz) (r=-.52, P=.006) and inversely with baroreflex sensitivity (r=-.60, P=.005). When the patients were divided into two groups according to the chemosensitivity of age-matched normal controls (above and below mean+2 SDs of chemosensitivity of control subjects), those above the normal range revealed more impaired autonomic balance, ie, lower baroreflex sensitivity (1.4 +/- 1.3 versus 5.0 +/- 1.5 ms/mm Hg, P<.0001) and depressed values of low-frequency power (2.5 +/- 1.8 versus 4.1 +/- 0.8 ln ms2, P<.005) compared with those with normal chemosensitivity. Transient hyperoxia did not alter heart rate or systolic pressure but resulted in an increase in HRV and an improvement in baroreflex sensitivity. CONCLUSIONS A link between increased peripheral chemosensitivity and impaired autonomic control, including baroreflex inhibition, is demonstrated. The clinical importance of this phenomenon warrants further investigation.
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Anker SD, Chua TP, Ponikowski P, Harrington D, Swan JW, Kox WJ, Poole-Wilson PA, Coats AJ. Hormonal changes and catabolic/anabolic imbalance in chronic heart failure and their importance for cardiac cachexia. Circulation 1997; 96:526-34. [PMID: 9244221 DOI: 10.1161/01.cir.96.2.526] [Citation(s) in RCA: 549] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The role of hormonal and cytokine abnormalities in the development of cardiac cachexia remains obscure. METHODS AND RESULTS Healthy control subjects (n=16) and patients with chronic heart failure (CHF), classified clinically as cachectic (8% to 35% weight loss over > or = 6 months before study, n=16) or noncachectic (n=37), were assessed for markers of disease severity (maximal oxygen consumption, left ventricular ejection fraction, NYHA functional class). These markers were compared with plasma concentrations of potentially important anabolic and catabolic factors. The degree of neurohormonal activation and catabolic/anabolic imbalance was closely related to wasting but not to conventional measures of the severity of heart failure. Compared with control subjects and noncachectic patients, cachectic patients had reduced plasma sodium and increased norepinephrine, epinephrine (all P<.0001), cortisol, tumor necrosis factor (TNF)-alpha (both P<.002), and human growth hormone (P<.05). Insulin-like growth factor-1, testosterone, and estrogen were similar in all groups. Insulin was increased only in the noncachectic patients (P<.005 versus control subjects). Dehydroepiandrosterone was reduced in the cachectic patients (P<.02 versus control subjects). Insulin, cortisol, TNF-alpha, and norepinephrine correlated independently with wasting in CHF (P<.05; multiple regression of these four factors versus percent ideal weight, R2=.50, P<.0001). CONCLUSIONS Cachexia is more closely associated with hormonal changes in CHF than conventional measures of the severity of CHF. This study suggests that the syndrome of heart failure progresses to cardiac cachexia if the normal metabolic balance between catabolism and anabolism is altered.
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Harrington D, Clark AL, Chua TP, Anker SD, Poole-Wilson PA, Coats AJ. Effect of reduced muscle bulk on the ventilatory response to exercise in chronic congestive heart failure secondary to idiopathic dilated and ischemic cardiomyopathy. Am J Cardiol 1997; 80:90-3. [PMID: 9205030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Changing the exercising muscle group alters the ventilatory response to exercise in chronic heart failure. The recognized muscle abnormalities in congestive heart failure may thus contribute to the ventilatory abnormalities of this condition.
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Ponikowski P, Anker SD, Chua TP, Szelemej R, Piepoli M, Adamopoulos S, Webb-Peploe K, Harrington D, Banasiak W, Wrabec K, Coats AJ. Depressed heart rate variability as an independent predictor of death in chronic congestive heart failure secondary to ischemic or idiopathic dilated cardiomyopathy. Am J Cardiol 1997; 79:1645-50. [PMID: 9202356 DOI: 10.1016/s0002-9149(97)00215-4] [Citation(s) in RCA: 304] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
After acute myocardial infarction, depressed heart rate variability (HRV) has been proven to be a powerful independent predictor of a poor outcome. Although patients with chronic congestive heart failure (CHF) have also markedly impaired HRV, the prognostic value of HRV analysis in these patients remains unknown. The aim of this study was to investigate whether HRV parameters could predict survival in 102 consecutive patients with moderate to severe CHF (90 men, mean age 58 years, New York Heart Association [NYHA] class II to IV, CHF due to idiopathic dilated cardiomyopathy in 24 patients and ischemic heart disease in 78 patients, ejection fraction [EF], 26%; peak oxygen consumption, 16.9 ml/kg/min) after exclusion of patients in atrial fibrilation with diabetes or with chronic renal failure. In the prognostic analysis (Cox proportional-hazards model, Kaplan-Meier survival analysis), the following factors were investigated: age, CHF etiology, NYHA class, EF, peak oxygen consumption, presence of ventricular tachycardia on Holter monitoring, and HRV measures derived from 24-hour electrocardiography monitoring, calculated in the time (standard deviation of all normal RR intervals [SDNN], standard deviation of 5-minute RR intervals [SDANN], mean of all 5-minute standard deviations of RR intervals [SD], root-mean-square of difference of successive RR intervals [rMSSD], and percentage of adjacent RR intervals >50 ms different [pNN50]) and frequency domain (total power [TP], power within low-frequency band [LF], and power within high-frequency band [HF]). During follow-up of 584 +/- 405 days (365 days in all who survived), 19 patients (19%) died (mean time to death: 307 +/- 315 days, range 3 to 989). Cox's univariate analysis identified the following factors to be predictors of death: NYHA (p = 0.003), peak oxygen consumption (p = 0.01), EF (p = 0.02), ventricular tachycardia on Holter monitoring (p = 0.05), and among HRV measures: SDNN (p = 0.004), SDANN (p = 0.003), SD (p = 0.02), and LF (p = 0.003). In multivariate analysis, HRV parameters (SDNN, SDANN, LF) were found to predict survival independently of NYHA functional class, EF, peak oxygen consumption, and ventricular tachycardia on Holter monitoring. The Kaplan-Meier survival curves revealed SDNN < 100 ms to be a useful risk factor; 1-year survival in patients with SDNN < 100 ms was 78% when compared with 95% in those with SDNN > 100 ms (p = 0.008). The coexistence of SDNN < 100 ms and a peak oxygen consumption < 14 ml/kg/min allowed identification of a group of 18 patients with a particularly poor prognosis (1-year survival 63% vs 94% in the remaining patients, p <0.001). We conclude that depressed HRV on 24-hour ambulatory electrocardiography monitoring is an independent risk factor for a poor prognosis in patients with CHF. Whether analysis of HRV could be recommended in the risk stratification for better management of patients with CHF needs further investigation.
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Chua TP, Ponikowski P, Harrington D, Anker SD, Webb-Peploe K, Clark AL, Poole-Wilson PA, Coats AJ. Clinical correlates and prognostic significance of the ventilatory response to exercise in chronic heart failure. J Am Coll Cardiol 1997; 29:1585-90. [PMID: 9180123 DOI: 10.1016/s0735-1097(97)00078-8] [Citation(s) in RCA: 392] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES This study sought to investigate the clinical characteristics of patients with chronic heart failure and an increased ventilatory response to exercise and to examine the prognostic usefulness of this response. BACKGROUND The ventilatory response to exercise is increased in many patients with chronic heart failure and may be characterized by the regression slope relating minute ventilation to carbon dioxide output (VE-VCO2 slope) during exercise. METHODS One hundred seventy-three consecutive patients (155 men; mean [+/-SD] age 59.8 +/- 11.5 years; radionuclide left ventricular ejection fraction [LVEF] 28.4 +/- 14.6%) underwent cardiopulmonary exercise testing (peak oxygen consumption 18.5 +/- 7.3 ml/kg per min; VE-CO2 slope 34.8 +/- 10.6) over a 2-year period. Using 1.96 standard deviations above the mean VE-VCO2 slope of 68 healthy age-matched subjects (mean slope 26.3 +/- 4.1), we defined a high ventilatory response to exercise as a slope >34. RESULTS Eighty-three patients (48%) had an increased VE-VCO2 slope (mean 43.1 +/- 8.9). There was a difference in age (62.2 vs. 57.3 years, p = 0.005), New York Heart Association functional class (2.9 vs. 2.1, p < 0.001), LVEF (24.7 vs. 31.9%, p = 0.0016), peak oxygen consumption (14.9 vs. 21.7 ml/kg per min, p < 0.0001) and radiographic cardiothoracic ratio (0.58 vs. 0.55, p = 0.002) between these patients and those with a normal slope. In the univariate Cox proportional hazards model, the E-VCO2 slope was an important prognostic factor (p < 0.0001). In the multivariate Cox analyses using several variables (age, peak oxygen consumption, VE-VCO2 slope and LVEF), the VE-VCO2 slope gave additional prognostic information (p = 0.018) beyond peak oxygen consumption (p = 0.022). Kaplan-Meier survival curves at 18 months demonstrated a survival rate of 95% in patients with a normal VE-VCO2 slope compared with 69% in those with a high slope (p < 0.0001). CONCLUSIONS A high VE-VCO2 slope selects patients with more severe heart failure and is an independent prognostic marker. The VE-VCO2 slope may be used as a supplementary index in the assessment of patients with chronic heart failure.
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Gunning MG, Chua TP, Harrington D, Knight CJ, Burman E, Pennell DJ, Pepper J, Fox K, Underwood SR. Hibernating myocardium: clinical and functional response to revascularisation. Eur J Cardiothorac Surg 1997; 11:1105-12. [PMID: 9237595 DOI: 10.1016/s1010-7940(97)01211-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE We assessed the effects of coronary bypass grafting on left ventricular (LV) function, exercise capacity and symptom profile in patients with LV impairment and evaluated the role of identifying myocardial hibernation in a prospective non-randomised study. METHODS Of 120 patients screened, 47 patients with LV ejection fraction < 35% and three vessel coronary artery disease were studied. All underwent stress/redistribution and separate day rest/redistribution T1-201 imaging together with cine MRI at enrolment, and cine MRI at follow-up. Group 1, 30 patients undergoing bypass surgery, underwent symptom limited treadmill exercise testing with peak VO2 measurement, and symptom profile evaluation less than 3 months before, and 3-6 months after operation. Revascularisation was assessed by post-operative T1-201 imaging and repeat coronary angiography. Group 2, 17 patients treated on medical therapy alone underwent symptom profile assessment at enrolment and follow-up for those who survived. Segmental hibernation was defined as the equivalent of greater than 50% of maximal T1-201 uptake where wall motion was severely impaired on resting imaging. Patients were considered to be hibernating where two of nine LV segments fulfilled these criteria. RESULTS In group 1, five patients died (17%), peri-or post-operatively, two defaulted and 23 attended follow-up studies. In group 2, three patients died prior to follow-up (18%). In the surgical group there was an increase in mean LVEF from 24.0 +/- 8% to 29.7 +/- 11% (P < 0.05) while in the medical group there was a fall from 25.7 +/- 10% to 20.6 +/- 8% (P < 0.05). In group 1, the mean NYHA dyspnoea grade improved from 2.7 to 1.4 while in the medical group it was unchanged, 2.6 to 2.5. In patients with myocardial hibernation identified pre-operatively, 18/19 (95%) improved LVEF after CABG compared with 2/4 (50%) of patients without hibernation. 17/19 (86%) patients with hibernation improved NYHA dyspnoea class compared with 2/4 (50%) of patients without. 60/93 (65%) of hibernating segments improved function after revascularisation while 47/53 (89%) hibernating segments showed no improvement on medical therapy alone. CONCLUSION In patients with severe LV impairment with myocardial hibernation, coronary artery bypass grafting improves both global and regional systolic LV function, and symptom profile. Medical treatment of patients with LV impairment and myocardial hibernation does not improve LV contractile function or symptoms. Both surgical and medical therapy carry a high mortality rate.
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Abstract
A major aim in treating patients with chronic heart failure is to improve exercise capacity and quality of life. Experimental evidence does not support the view that central hemodynamic disturbance is the sole determinant of exercise capacity. Rather, multiple other factors including abnormalities of ventilatory control, the lungs, the peripheral circulation, and skeletal muscle appear to combine to generate symptoms and limit exercise.
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Knight C, Kurbaan AS, Seggewiss H, Henein M, Gunning M, Harrington D, Fassbender D, Gleichmann U, Sigwart U. Nonsurgical septal reduction for hypertrophic obstructive cardiomyopathy: outcome in the first series of patients. Circulation 1997; 95:2075-81. [PMID: 9133518 DOI: 10.1161/01.cir.95.8.2075] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Some patients with hypertrophic obstructive cardiomyopathy may gain symptomatic relief from a reduction in the extent of obstruction to left ventricular outflow. We present the outcome of the first series of patients treated with an alternative method of gradient reduction using catheter techniques. METHODS AND RESULTS Eighteen patients were treated with selective intracoronary alcohol injection to induce localized septal infarction. Patients underwent echocardiographic measurement of left ventricular dimensions and Doppler echocardiographic evaluation of left ventricular outflow tract gradients before the procedure, on the first postoperative day, and at a median follow-up of 3 months after the procedure. In addition, patients underwent exercise testing and symptom evaluation before and 3 months after nonsurgical septal reduction. There was a significant reduction in left ventricular outflow tract obstruction after the procedure (preprocedure, 67 mm Hg [95% CI, 48 to 87 mm Hg]; postprocedure, 25 mm Hg [95% CI, 16 to 34 mm Hg]; P=.0006), which persisted at 3-month follow-up (22 mm Hg [95% CI, 12 to 32 mm Hg]; P=.001). This was associated with a significant improvement in symptoms. There was a small but not significant increase in exercise capacity (n=10; preprocedure, 418 seconds [95% CI, 273 to 563 seconds]; postprocedure, 452 seconds [95% CI, 283 to 621 seconds). Left ventricular dimensions were not significantly altered by nonsurgical septal reduction. CONCLUSIONS Nonsurgical septal reduction significantly reduces left ventricular outflow tract obstruction and improves symptoms in some patients with hypertrophic obstructive cardiomyopathy. The technique may provide an alternative to surgical myomectomy in selected patients.
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Anker SD, Ponikowski P, Varney S, Chua TP, Clark AL, Webb-Peploe KM, Harrington D, Kox WJ, Poole-Wilson PA, Coats AJ. Wasting as independent risk factor for mortality in chronic heart failure. Lancet 1997; 349:1050-3. [PMID: 9107242 DOI: 10.1016/s0140-6736(96)07015-8] [Citation(s) in RCA: 1011] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Wasting in chronic heart failure (CHF) has long been known but is little investigated. We sought to find out whether the cachectic state in CHF provides additional prognostic information about all-cause mortality. METHODS Between June, 1993, and May, 1995, we studied 171 consecutive patients with CHF (mean age 60 years [SD 11; range 27-86]; 17 female). We assessed exercise capacity (peak oxygen consumption; mean 17.5 mL kg-1 min-1 [6.7]), functional status (New York Heart Association [NYHA] class: 21 class I, 63 class II, 68 class III, 19 class IV), and left-ventricular ejection fraction (mean 30% [SD 15]; n = 115). The cachectic status was defined prospectively as a non-intentional documented weight loss of at least 7.5% of previous normal weight (28 patients; range 9-36% or 6-30 kg) during at least 6 months. The Cox proportional-hazards model was used to assess the association of variables with survival, and Kaplan-Meier cumulative survival plots were constructed to estimate the influence of risk factors. FINDINGS At the end of follow-up in November, 1996, 49 patients had died (after a mean 324 days [SD 283]). The mean follow-up of the survivors was 834 days (SD 186; range 549-1269). The cachectic state was predictive of 18-month mortality independent of age, NYHA class, left-ventricular ejection fraction, and peak oxygen consumption. Mortality in the cachectic patients (n = 28) was 18% at 3 months, 29% at 6 months, 39% at 12 months, and 50% at 18 months. Patients who had a peak oxygen consumption below 14 mL kg-1 min-1 (n = 53) had mortality at 3, 6, 12, and 18 months of 19%, 30%, 40%, and 51%. 18-month survival was 23% (95% CI 0-46) for the 13 patients with both of these risk factors (cachexia and low peak oxygen consumption) compared with 93% (88-98) in those (n = 103) with neither risk factor (p < 0.0001). INTERPRETATION The cachectic state is a strong independent risk factor for mortality in patients with CHF. Combined with a low peak oxygen consumption, it identifies a subset of patients at extremely high risk of death. Assessment of cachexia should be included in transplant programmes and studies that investigate the effect of interventions by survival analyses.
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