51
|
Steinfort DP, Russell PA, Tsui A, White G, Wright G, Irving LB. Interobserver agreement in determining non-small cell lung cancer subtype in specimens acquired by EBUS-TBNA. Eur Respir J 2012; 40:699-705. [PMID: 22323573 DOI: 10.1183/09031936.00109711] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) may diagnose suspected lung cancer. Determination of non-small cell lung cancer (NSCLC) subtype may guide therapy in select patients. Small-volume biopsies may be subject to significant interobserver variability in subtype determination. Three pathologists independently reviewed specimens from 60 patients who underwent EBUS-TBNA for diagnosis/staging of suspected/known NSCLC. Smear, haematoxylin and eosin (H&E) and immunohistochemistry (IHC) specimens were reviewed without reference to other specimen types obtained from the same patient. Final diagnoses, and degree of confidence in the diagnosis, were recorded for each specimen. Almost perfect agreement was seen for distinguishing between small cell lung cancer and NSCLC for all specimen types. Agreement in determination of NSCLC subtype for smear, H&E and IHC specimens was slight (κ=0.095, 95% CI -0.164-0.355), fair (κ=0.278, 95% CI 0.075-0.481) and moderate (κ=0.564, 95% CI 0.338-0.740), respectively. Perfect agreement was seen when all three observers were confident of diagnoses made on IHC specimens. Interobserver agreement in interpretation of EBUS-TBNA specimens is moderate for determination of NSCLC subtype. Agreement is highest following examination of IHC specimens. Clinicians should be aware of the degree of pathologist confidence in the tissue diagnosis prior to commencement of subtype-specific therapy for NSCLC.
Collapse
|
52
|
Blombery PA, Russell PA, Daffy JR. An unusual case of recurrent fever, jaundice and right upper quadrant pain. Med J Aust 2009; 191:396-7. [PMID: 19807633 DOI: 10.5694/j.1326-5377.2009.tb02849.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2009] [Accepted: 06/10/2009] [Indexed: 11/17/2022]
|
53
|
Hengel CL, Russell PA, Gould PA, Kaye DM. Subacute Anthracycline Cardiotoxicity. Heart Lung Circ 2006; 15:59-61. [PMID: 16473794 DOI: 10.1016/j.hlc.2005.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 03/09/2005] [Accepted: 06/13/2005] [Indexed: 11/19/2022]
Abstract
We describe the case of 25-year-old man, with acute myeloid leukaemia, who presented with a myopericarditis syndrome 17 days post consolidation chemotherapy with high dose cytarabine and idarubicin. Transthoracic echocardiography showed marked transient increased left ventricular wall thickness associated with normal systolic contraction. In conjunction, pulsed tissue Doppler analysis revealed low early diastolic annular velocities, consistent with diastolic dysfunction. Endomyocardial biopsy showed severe interstitial myocardial oedema in the absence of a cellular infiltrate or myofibre damage. We believe this is the first case of subacute anthracycline toxicity described with the pathological findings of isolated myocardial oedema.
Collapse
|
54
|
McWilliams TJ, Levvey BJ, Russell PA, Milne DG, Snell GI. Interstitial pneumonitis associated with sirolimus: a dilemma for lung transplantation. J Heart Lung Transplant 2003; 22:210-3. [PMID: 12581772 DOI: 10.1016/s1053-2498(02)00564-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Rapamycin/sirolimus (SR), trade named Rapammune (Wyeth-Ayerst, Sydney, Australia), is a potent immunosuppressive drug associated with myelosuppression, hypertension, hyperlipidemia, and infection. Rapamycin/sirolimus-induced pneumonitis has been described previously in renal transplant recipients, and this report describes a stable heart-lung transplant recipient who developed a pulmonary infiltrate that reversed after ceasing SR therapy. We believe that immunosuppression-induced pneumonitis in a lung allograft is a serious dilemma for lung transplant physicians
Collapse
|
55
|
Abstract
The aesthetic significance of the golden-section rectangle was tested in two studies designed to obviate some of the criticisms of earlier experiments. In the first, employing the method of use, the mean sides-ratios of samples of paintings from five subject-matter categories (landscape, still life, head-and-shoulders portrait, upper-body portrait, full-length portrait) provided no evidence for the significance of the golden section. However, the sides ratio of portraits varied between categories in ways that were consistent with the requirements of the proportions of the subject matter. In the second study, using the method of production, participants produced the most pleasing four-sided shape, under four instruction conditions. Under a 'portrait painting' condition and a 'landscape painting' condition, the mean sides-ratios differed significantly from the golden section. Under two 'context free' geometric shape conditions--horizontal rectangle and vertical rectangle--the mean sides-ratio approximated the golden section. The results are discussed in terms of the methodological requirements for a valid test of the aesthetic significance of the golden section and the possibility that this ratio may indeed have special significance.
Collapse
|
56
|
Kenmuir SVJ, Challis LJ, Heraud AP, Russell PA. The role of surface phonon scattering in the growth and decay of frequency-crossing signals. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/20/23/024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
57
|
Russell PA, Pharoah PD, De Foy K, Ramus SJ, Symmonds I, Wilson A, Scott I, Ponder BA, Gayther SA. Frequent loss of BRCA1 mRNA and protein expression in sporadic ovarian cancers. Int J Cancer 2000; 87:317-21. [PMID: 10897034 DOI: 10.1002/1097-0215(20000801)87:3<317::aid-ijc2>3.0.co;2-b] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Germline mutations in the BRCA1 gene cause inherited susceptibility to breast and ovarian cancers. However, somatic mutations of BRCA1 are rare in sporadic breast and ovarian tumours. To establish whether BRCA1 is altered during the development of sporadic ovarian cancer by mechanisms other than somatic mutation, we have analysed 57 sporadic epithelial ovarian tumours for BRCA1 protein and RNA expression. Reduced or absent protein expression was observed in 90% of tumours. Decreased protein expression was significantly associated with a reduction in the levels of RNA expression. Somatic mutations of BRCA1 and LOH at the BRCA1 locus were detected in 3.5% and 44% of informative tumours, respectively; there was no significant correlation between the levels of protein and RNA expression and the DNA mutation and/or LOH status. Together, these data suggest that expression of BRCA1 is down-regulated at the level of transcription during the development of sporadic ovarian cancers.
Collapse
|
58
|
Russell PA. The aesthetics of rectangle proportion: effects of judgment scale and context. AMERICAN JOURNAL OF PSYCHOLOGY 2000; 113:27-42. [PMID: 10742842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Two experiments examined preference for rectangle proportion, using a method that allowed participants to adjust 1 dimension of a rectangle to achieve the most preferred proportion. Instructing participants to use an interestingness response scale resulted in a preference for rectangles having more extreme sides ratios, compared with pleasingness or preferability scales. Instructing participants to produce a rectangle representing the preferred proportions of a painting or a kitchen tile shifted the preferred sides ratio toward a less extreme value than did a no-context rectangle instruction. Implications of the results for the findings of experiments that seek evidence for the special significance of particular ratios, such as the golden section, are discussed.
Collapse
|
59
|
Hosie JA, Russell PA, Gray CD, Scott C, Hunter N, Banks JS, Macaulay MC. Knowledge of display rules in prelingually deaf and hearing children. J Child Psychol Psychiatry 2000; 41:389-98. [PMID: 10784086] [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: 02/16/2023]
Abstract
Deaf children of elementary and secondary school age participated in a study designed to examine their understanding of display rules, the principles governing the expression and concealment of emotion in social situations. The results showed that deaf children's knowledge of display rules, as measured by their reported concealment of emotion, was comparable to that of hearing children of the same age. However, deaf children were less likely to report that they would conceal happiness and anger. They were also less likely to produce reasons for concealing emotion and a smaller proportion of their reasons were prosocial, that is, relating to the feelings of others. The results suggest that the understanding of display rules (which function to protect the feelings of other people) may develop more gradually in deaf children raised in a spoken language environment than it does in hearing children.
Collapse
|
60
|
Russell PA, Hosie JA, Gray CD, Scott C, Hunter N, Banks JS, Macaulay MC. The development of theory of mind in deaf children. J Child Psychol Psychiatry 1998; 39:903-10. [PMID: 9758198] [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: 02/08/2023]
Abstract
Deaf children aged 4 to 16 years were given a false-belief test of theory of mind. Although the children experienced difficulty with the test, relative to hearing children, confirming a report by Peterson and Siegal (1995), performance was age-related, with a significantly higher proportion of 13- to 16-year-olds passing the test. It was concluded that deaf children raised in a spoken language environment show a developmental delay in theory of mind acquisition. This delay is consistent with the assumption that their early opportunities for learning about mental states are relatively restricted and that the normal development of theory of mind is dependent upon such opportunities.
Collapse
|
61
|
Clarke DM, Russell PA, Polglase AL, McKenzie DP. Psychiatric disturbance and acute stress responses in surgical patients. THE AUSTRALIAN AND NEW ZEALAND JOURNAL OF SURGERY 1997; 67:115-8. [PMID: 9068552 DOI: 10.1111/j.1445-2197.1997.tb01914.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND A number of reports have appeared of post-traumatic stress symptoms occurring in physically ill patients. This study sought to measure the extent of psychiatric disturbance and acute post-traumatic stress reactions occurring in surgical inpatients, and to examine their relationship with the stress of illness and hospitalization and the personal coping style of the patient. METHODS Thirty-seven admissions to a general surgical unit were assessed on admission and immediately prior to discharge. Measures were made of depression, anxiety, cognitive impairment, post-traumatic stress symptoms, severity of illness, level of physical functioning, degree of hospital stress and coping style. RESULTS There was a significant reduction in anxiety scores postoperatively. Twenty-seven per cent of patients developed high levels of acute post-traumatic stress symptoms and these correlated with depression at admission and intra-hospital stress. Depression at discharge was related to depression at admission, physical functioning and coping style. In general, avoidance and acceptance-resignation were associated with a poorer psychiatric outcome. CONCLUSIONS Postoperative psychiatric disturbance, including acute stress symptoms, can be understood as a reaction to the 'trauma' of illness and hospitalization, predisposed to by pre-existing depression. Interventions could be directed at screening for at-risk patients, minimizing stress, and encouraging adaptive mechanisms of coping in patients.
Collapse
|
62
|
Russell PA. Integration in the South African Medical Service. JOURNAL OF THE ROYAL NAVAL MEDICAL SERVICE 1996; 82:18-24. [PMID: 8776933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
63
|
Gayther SA, Warren W, Mazoyer S, Russell PA, Harrington PA, Chiano M, Seal S, Hamoudi R, van Rensburg EJ, Dunning AM, Love R, Evans G, Easton D, Clayton D, Stratton MR, Ponder BA. Germline mutations of the BRCA1 gene in breast and ovarian cancer families provide evidence for a genotype-phenotype correlation. Nat Genet 1995; 11:428-33. [PMID: 7493024 DOI: 10.1038/ng1295-428] [Citation(s) in RCA: 368] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mutations in the BRCA1 gene, discovered in 1994, are associated with an 80-90% lifetime risk of breast cancer. We have analysed 60 families with a history of breast and/or ovarian cancer for germline mutations in BRCA1. Twenty-two different mutations were detected in 32 families (53%), of which 14 are previously unreported. We observed a significant correlation between the location of the mutation in the gene and the ratio of breast to ovarian cancer incidence within each family. Our data suggest a transition in risk such that mutations in the 3' third of the gene are associated with a lower proportion of ovarian cancer. Haplotype analysis supports previous data which suggest some BRCA1 mutation carriers have common ancestors; however, we have found at least two examples where recurrent mutations appear to have arisen independently.
Collapse
|
64
|
Kent AJ, Hardy GA, Hawker P, Rampton VW, Newton MI, Russell PA, Challis LJ. Detection of heat pulses by the two-dimensional electron gas in a silicon device. PHYSICAL REVIEW LETTERS 1988; 61:180-182. [PMID: 10039053 DOI: 10.1103/physrevlett.61.180] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
65
|
Denniss AR, Ross DL, Cody DV, Russell PA, Young AA, Richards DA, Uther JB. Randomized controlled trial of prophylactic antiarrhythmic therapy in patients with inducible ventricular tachyarrhythmias after recent myocardial infarction. Eur Heart J 1988; 9:746-57. [PMID: 3169044 DOI: 10.1093/eurheartj/9.7.746] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Survivors of acute myocardial infarction who had inducible sustained ventricular tachyarrhythmias at programmed stimulation 1-4 weeks after infarction were recruited to a randomized pilot trial of Class I antiarrhythmic drugs, in an attempt to determine whether their mortality and risk of spontaneous ventricular tachycardia and fibrillation could be reduced by treatment. Of 136 eligible patients, 96 (71%) joined the trial and 47 were randomized to 'no treatment' and 49 were randomized to 'treatment' (quinidine, disopyramide or mexiletine given to attain 'therapeutic' serum levels). During follow-up, the two groups fared similarly. For the 'treatment' and 'no treatment' groups, the respective 3-year probabilities of remaining incident-free were:cardiac death, 0.91 vs 0.89; instantaneous death + non-fatal ventricular tachyarrhythmias, 0.87 vs 0.87; cardiac death + non-fatal ventricular tachyarrhythmias, 0.83 vs 0.85. The highest risk patients with inducible ventricular tachycardia fared similarly in the 'treatment' and 'no treatment' groups. The respective probabilities of remaining incident-free were: cardiac death, 0.89 vs 0.88; instantaneous death + non-fatal ventricular tachyarrhythmias, 0.79 vs 0.84; cardiac death + non-fatal ventricular tachyarrhythmias, 0.76 vs 0.77. We conclude that prophylactic Class I antiarrhythmic drug therapy with quinidine, disopyramide or mexiletine given to achieve a 'therapeutic' serum level does not appear to alter the prognosis of patients with inducible ventricular tachyarrhythmias after myocardial infarction.
Collapse
|
66
|
Denniss AR, Richards DA, Cody DV, Russell PA, Young AA, Ross DL, Uther JB. Correlation between signal-averaged electrocardiogram and programmed stimulation in patients with and without spontaneous ventricular tachyarrhythmias. Am J Cardiol 1987; 59:586-90. [PMID: 3825898 DOI: 10.1016/0002-9149(87)91174-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
This study examined the incidence of delayed ventricular activation on signal-averaged electrocardiograms and the incidence of inducible sustained ventricular tachycardia (VT) at programmed stimulation (1 or 2 extrastimuli) in patients with and patients without spontaneous ventricular tachyarrhythmias. The correlation between delayed ventricular activation and inducible VT was investigated in 371 patients with acute myocardial infarction (AMI). In 32 patients with no ventricular disease and no spontaneous arrhythmias (group I), ventricular activation time averaged 115 +/- 2 ms, compared with 166 +/- 3 ms (p less than 0.001) for 65 patients with spontaneous ventricular tachyarrhythmias late after AMI (group II). In AMI patients with no spontaneous arrhythmias, ventricular activation time averaged 133 +/- 2 ms for 306 patients studied 1 to 4 weeks after AMI (group III) and 130 +/- 2 ms for 67 patients studied 3 to 12 months after AMI (group IV). The values for group III and group IV patients were each significantly higher than for group I (p less than 0.001), but lower than that for group II (p less than 0.001). The incidence of delayed ventricular activation was 89% for group II, 26% for group III and 18% for group IV. Sustained VT was not inducible in group I patients, but was inducible in 78% of group II (p less than 0.001 vs group I) and 20% of group III (p less than 0.05 vs group I; p less than 0.001 vs group II) (group IV was not studied).(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
67
|
Denniss AR, Richards DA, Cody DV, Russell PA, Young AA, Cooper MJ, Ross DL, Uther JB. Prognostic significance of ventricular tachycardia and fibrillation induced at programmed stimulation and delayed potentials detected on the signal-averaged electrocardiograms of survivors of acute myocardial infarction. Circulation 1986; 74:731-45. [PMID: 3757187 DOI: 10.1161/01.cir.74.4.731] [Citation(s) in RCA: 366] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The relative prognostic significance of ventricular tachycardia and ventricular fibrillation inducible at programmed stimulation within 1 month of acute myocardial infarction was compared in a prospective study of 403 clinically well survivors of transmural infarction who were 65 years old or younger. The prognostic significance of delayed potentials on the signal-averaged electrocardiogram was also examined in a subset of 306 patients without bundle branch block. Among the study patients, 20% had inducible ventricular tachycardia, 14% had inducible ventricular fibrillation, and 66% had no inducible arrhythmias. The 2 year probability of remaining free from cardiac death or nonfatal ventricular tachycardia or fibrillation was 0.73 for those with inducible ventricular tachycardia, 0.93 for those with inducible ventricular fibrillation, and 0.92 for those with no inducible arrhythmias. The cycle length of inducible ventricular tachycardia was 230 msec or more in 70% of the patients with inducible tachycardia who died. Of the patients studied by signal-averaged electrocardiography, 26% had delayed potentials. At 2 years, the probability of remaining free from cardiac death or nonfatal ventricular tachycardia or fibrillation was 0.73 for patients with delayed potentials and 0.95 for patients with no delayed potentials. There was a significant correlation (p less than .001) between the presence of delayed potentials and the ability to induce ventricular tachycardia. In conclusion, in survivors of recent infarction who have not had spontaneous ventricular tachycardia or fibrillation, inducible tachycardia (but not inducible fibrillation) at programmed stimulation predicts a significant risk of death or spontaneous tachycardia or fibrillation. A similar risk is found for patients with delayed potentials on the signal-averaged electrocardiogram.
Collapse
|
68
|
Denniss AR, Ross DL, Richards DA, Cody DV, Russell PA, Young AA, Uther JB. Effect of antiarrhythmic therapy on delayed potentials detected by the signal-averaged electrocardiogram in patients with ventricular tachycardia after acute myocardial infarction. Am J Cardiol 1986; 58:261-5. [PMID: 3739914 DOI: 10.1016/0002-9149(86)90059-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The ability of class I and class II antiarrhythmic drugs to either abolish delayed potentials or modify their timing was investigated in 39 patients with spontaneous ventricular tachycardia (VT) after myocardial infarction. Before the study all patients had delayed potentials on the signal-averaged electrocardiogram and inducible VT with programmed stimulation. These investigations were repeated during 67 trials of oral antiarrhythmic therapy (mexiletine 25, quinidine 24, metoprolol 13, disopyramide 2, procainamide 1, drug combinations 2). Delayed potentials were abolished in only 5 trails (7%), which was within the baseline variability of 8.5% for detection of delayed potentials. In the 7 trials in which VT inducibility was suppressed, delayed potentials persisted in 6 and mean ventricular activation time was virtually unchanged (151 ms before drug therapy, 152 ms after). Quinidine, mexiletine and metoprolol caused no consistent change in ventricular activation time. There was also no change in mean ventricular activation time (164 ms before and 163 ms after drug treatment) in patients in whom spontaneous VT did not recur with drug therapy during follow-up. Thus, the tested antiarrhythmic drugs had no consistent effects on presence or timing of delayed potentials on the signal-averaged electrocardiogram, even when VT inducibility was suppressed or recurrence of spontaneous VT was prevented.
Collapse
|
69
|
Denniss AR, Baaijens H, Cody DV, Richards DA, Russell PA, Young AA, Ross DL, Uther JB. Value of programmed stimulation and exercise testing in predicting one-year mortality after acute myocardial infarction. Am J Cardiol 1985; 56:213-20. [PMID: 4025159 DOI: 10.1016/0002-9149(85)90837-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The ability of programmed ventricular stimulation and exercise testing to predict 1-year mortality after acute myocardial infarction (AMI) was investigated in 228 clinically well survivors of AMI. Patients with inducible ventricular tachycardia (VT) or ventricular fibrillation (VF) had a higher mortality rate than those without inducible arrhythmias (26% vs 6%, p less than 0.001). Exercise-induced ST-segment change of 2 mm or more was associated with a higher mortality rate than ST change of less than 2 mm (11% vs 4%, 0.05 less p less than 0.10). Of patients who had both tests, 62% had no inducible ventricular tachycardia or ventricular fibrillation and ST change of less than 2 mm, and only 1% died during the first year. Thus, in clinically well survivors of AMI, programmed stimulation is a powerful predictor of first-year mortality; programmed stimulation and exercise testing together predict virtually all deaths within the first year, and they can identify a large group of patients with a very low mortality rate.
Collapse
|
70
|
Richards DA, Cody DV, Denniss AR, Russell PA, Young AA, Uther JB. A new protocol of programmed stimulation for assessment of predisposition to spontaneous ventricular arrhythmias. Eur Heart J 1983; 4:376-82. [PMID: 6617683 DOI: 10.1093/oxfordjournals.eurheartj.a061483] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We have devised a simple method for identifying predisposition to spontaneous sustained ventricular fibrillation (VF) and tachycardia (VT). A standardized protocol of programmed stimulation was applied to 111 control subjects without ventricular disease and with no history of VF or VT (Group I) and to 27 patients with previous myocardial infarction and documented spontaneous (in the absence of evidence of further acute myocardial ischaemia) VF or VT (Group II). The stimulation protocol consisted of single and paired ventricular extra stimuli introduced during ventricular drive at the right ventricular apex and outflow tract, at twice diastolic threshold current intensity and at 20 mA. None of the Group I subjects exhibited VF or sustained (more than 10 s) VT. In contrast sustained arrhythmias were induced in 24 (89%) of Group II patients. We conclude: In our study population, initiation of a sustained ventricular tachyarrhythmia at programmed stimulation was both a sensitive (89%) and specific (100%) indicator for predisposition to spontaneous VF and VT.
Collapse
|
71
|
Richards DA, Cody DV, Denniss AR, Russell PA, Young AA, Uther JB. Ventricular electrical instability: a predictor of death after myocardial infarction. Am J Cardiol 1983; 51:75-80. [PMID: 6129796 DOI: 10.1016/s0002-9149(83)80014-9] [Citation(s) in RCA: 193] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The results of a prospective study of ventricular electrical instability after myocardial infarction (MI) are presented. Ventricular electrical stability was assessed using a standardized protocol of programmed stimulation in 165 hemodynamically stable patients 6 to 28 days after acute MI. Ventricular electrical instability was defined as induction at programmed stimulation of ventricular fibrillation (VF) or ventricular tachycardia (VT) lasting at least 10 seconds. Of 165 MI survivors, 38 (23%) had ventricular electrical instability. No significant differences were noted between stable and unstable patients in terms of coronary prognostic index, elevation of serum creatine phosphokinase, coronary anatomy, site of MI, or frequency of VT within 48 hours of MI. The mean follow-up period was 8 months (range 0 to 12). There were 7 deaths in stable patients (5 from cardiogenic shock, 1 from septicemia, and 1 unwitnessed) and 10 deaths in unstable patients (8 instantaneous, 1 from cardiogenic shock, and 1 unwitnessed) during the subsequent year. In addition, 2 of 127 stable patients and 4 of 38 unstable patients had spontaneous VT from which they were satisfactorily resuscitated. Thus, the sensitivity of ventricular electrical instability as a predictor of instantaneous death or spontaneous VT was 86% and the specificity 83%. The predictive accuracy of the absence of ventricular electrical instability as an indicator for the absence of instantaneous death or spontaneous VT was 98%. The predictive accuracy of the presence of ventricular electrical instability as a predictor of instantaneous death or spontaneous VT was 32%. Thus, patients with ventricular electrical instability after MI have a high risk of instantaneous death within 1 year; patients without ventricular electrical instability after MI have a low risk of instantaneous death within 1 year; prospective studies of antiarrhythmic therapy and measures to prevent reinfarction and optimize left ventricular performance are required to determine whether instantaneous death can be prevented in unstable patients; and therapy to prevent reinfarction and optimize left ventricular performance may offer the best chance to improve prognosis in stable patients.
Collapse
|
72
|
Predecki P, Life L, Russell PA, Newman MM. Measurement of the activation time for platelet adhesion to foreign surfaces. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1980; 14:417-26. [PMID: 7400195 DOI: 10.1002/jbm.820140408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An apparatus is described which permitted a perfusant (lactated Ringer's solution) to be passed through a porous sample in a pulsatile manner with a square wave pressure profile. The "on" time, "off" time, number of cycles and pressure amplitude were separately controllable. Using this apparatus and immersing the sample in stirred, heparinized, human blood, there was a certain "off" time below which platelet adhesion to the sample abruptly ceased. The values of this "off" time, termed the activation time ta for platelet adhesion were approximately 0.5 sec for 0.2 micrometers pore size cellulose diacetate/nitrate (millipore filter) and approximately 0.3 sec for 0.2 micrometers polycarbonated (nuclepore filter). After a single cycle with a 5 sec "off" time, adhered platelets on both these materials showed pseudopodia, varying degrees of spreading and membrane perforation.
Collapse
|
73
|
Predecki P, Russell PA. Blood-compatible materials by fluid perfusion. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1977; 11:767-86. [PMID: 893493 DOI: 10.1002/jbm.820110511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The feasibility of preventing platelet adhesion to porous foreign surfaces in contact with blood by passing (perfusing) a physiologic fluid through the pores into the blood was tested. Porous-walled tubes of Teflon (Gore-tex) and aluminosilicate ceramic were perfused with lactated Ringer's solution at rates between 3.13 and 0.3 cc/min per cm2 of perfused surfaced and exposed to heparinized and unheparinized flowing human whole blood for periods of 3-6 min. Under these conditions, with 0.159 cm I.D. tubes and a mean blood flow rate of 8.3 cm/sec, the adhesion of all blood cells was prevented, compared with the adhesion of 1 to 8 X 10(6) platelets/cm2 on the nonperfused controls. The adhesion of plasma proteins was also markedly reduced as determined by bromophenol blue staining. The critical perfusion rate to prevent platelet adhesion to Gore-tex (0.5 micron pore size, 60% pore volume) was found to be between 0.04 and 0.3 cc/(min-cm2). The boundary layer produced by a perfused segment of porous tubing prevented platelet adhesion for several centimeters downstream from the perfusing segment under experimental conditions used.
Collapse
|
74
|
|
75
|
Russell PA, Williams DI. Effects of repeated testing on rats' locomotor activity in the open-field. Anim Behav 1973; 21:109-11. [PMID: 4706760 DOI: 10.1016/s0003-3472(73)80047-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|