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1.
Clin Case Rep ; 9(6): e04354, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34136254

ABSTRACT

Acute-onset presentation with breathlessness and calcific pericardial thickening encapsulating the heart. Extremely chylous pericardium, which is by itself rare, in combination with constriction assessed with multiple imaging modalities.

4.
Emerg Med J ; 26(7): 541-2, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19546284

ABSTRACT

A case is presented in which a 66-year-old man received thrombolysis for an acute ST elevation myocardial infarction (STEMI) within 6 minutes of developing chest pain. An ECG performed 10 minutes after thrombolysis showed complete resolution of the ST segment elevation and showed no other abnormality. An echocardiogram showed normal left ventricular function and there was no detectable myocardial necrosis, as evidenced by two negative troponin assays. The case clearly reinforces the benefits of the rapid delivery of thrombolysis when appropriate for patients with STEMI. Clinicians need to be aware of the benefits of early thrombolysis as laid out in the national service framework. Evidence for the early administration of thrombolysis, data from the Myocardial Infarction National Audit Project and the future with regard to improving thrombolysis times are discussed.


Subject(s)
Fibrinolytic Agents/therapeutic use , Myocardial Infarction/drug therapy , Myocardium/pathology , Tissue Plasminogen Activator/therapeutic use , Aged , Electrocardiography , Humans , Male , Necrosis/prevention & control , Tenecteplase
5.
Eur J Heart Fail ; 8(8): 869-73, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16714145

ABSTRACT

An interesting development in the field of heart failure has been the link between frequent premature ventricular contractions and cardiomyopathy. We report a patient whose frequent ventricular bigeminy resulted in left ventricular impairment that resolved after the use of non-contact mapping during radiofrequency ablation. A review of the literature regarding possible mechanisms is discussed. For the practicing clinician, the question of 'frequent' should be taken in context of symptoms and LV function. A single 24-h Holter monitor may not truly reflect the ectopic load. We recommend that if there is associated LV dysfunction and a causal link to frequent PVCs then suppression with radiofrequency ablation is a safe and effective treatment strategy.


Subject(s)
Cardiomyopathy, Dilated/etiology , Cardiomyopathy, Dilated/physiopathology , Ventricular Dysfunction, Left/complications , Ventricular Dysfunction, Left/physiopathology , Cardiomyopathy, Dilated/pathology , Electrocardiography , Female , Humans , Middle Aged , Time Factors
6.
Int J Cardiol ; 94(2-3): 173-6, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15093976

ABSTRACT

BACKGROUND: New generation portable super-C-arm imaging systems may offer an alternative means of performing coronary angiography at a lower cost compared with a fixed laboratory. We evaluated the use of one such system (GE-OEC 9800) in a district hospital setting. METHODS: The demographics, procedure and screening times, emitted radiation dose and diagnoses of the first 200 consecutive patients were obtained from a prospective database. Comparison between the portable and fixed systems were made by analysing results from similar cohorts of patients who underwent angiography by the same operators. Image quality was assessed in 23 patients, by an independent cardiologist, comparing the GE-OEC 9800 angiograms with repeat images using a fixed laboratory Philips (HM 3000) system within 3 months of the first study. RESULTS: The procedure time (mean (S.D.)) was 18.9 (0.8) min for the 200 cases. The screening time was 255 (15) s with an emitted radiation of 22.8 (1.4) Gy/cm(2). Comparison between the C-arm and fixed systems revealed significantly longer screening time (230.6 (14.6) vs. 157 (12.9) s, p<0.001), whilst the total radiation doses were not significantly different (21.1 (1.5) vs. 18.6 (1.11) Gy/cm(2)). Independently assessed image quality was satisfactory. The main variance in 57 lesions seen in the 23 patients using the angiograms obtained from the fixed laboratory as reference included overestimated stenosis (two lesions), underestimated stenosis (or subsequent disease progression) (four lesions), lack of appreciation of side-branch ostial involvement (two lesions) and vessel calcification (one lesion). CONCLUSIONS: Portable imaging systems can offer a reliable and cost-effective diagnostic coronary angiography service in a district hospital.


Subject(s)
Coronary Angiography/instrumentation , Coronary Artery Disease/diagnostic imaging , Diagnostic Imaging/instrumentation , Female , Hospitals, District , Hospitals, General , Humans , Male , Middle Aged
7.
Circulation ; 104(19): 2324-30, 2001 Nov 06.
Article in English | MEDLINE | ID: mdl-11696473

ABSTRACT

BACKGROUND: In chronic heart failure (CHF), overactivation of ergoreceptors (afferents sensitive to the metabolic effects of muscular work) may be a link between peripheral changes, sympathetic overactivation, and increased hemodynamic and ventilatory responses to exercise. The relationship between ergoreceptors, autonomic changes, and the progression of the syndrome has not yet been studied. METHODS AND RESULTS: Thirty-eight stable CHF patients (age, 57+/-1 years; ejection fraction, 26+/-2%) were compared with 12 age-matched normal control subjects. The ergoreflex contribution to the ventilatory and hemodynamic responses to exercise, together with peripheral and central chemoreceptor sensitivity, arterial baroreflex sensitivity, plasma norepinephrine, epinephrine, and heart rate variability, were measured. Enhanced ergoreflex effects on ventilation (78+/-2% versus 50+/-8%), peripheral chemosensitivity (0.6+/-0.4 versus 0.2+/-0.1 L/min per percent SaO(2)), and central chemosensitivity (2.9+/-0.2 versus 2.0+/-0.2 L. min(-1). mm Hg(-1)) and an impaired baroreflex function (4.1+/-0.6 versus 9.1+/-5.6 ms/mm Hg) were confirmed in CHF compared with control subjects (P<0.01 in all comparisons). Ergoreceptor overactivity was associated with a worse symptomatic state (NYHA class, P<0.05), lower exercise tolerance (peak VO(2), P<0.05), and pronounced exercise hyperventilation (VE/VCO(2), P<0.01). It was also a strong predictor of increased central chemosensitivity (independently of clinical parameters), baroreflex impairment, and sympathetic activation (plasma catecholamines and heart rate variability indexes; all P<0.05). In multivariate analysis, among all reflexes studied, the ventilatory component of the ergoreflex was the only independent predictor of peak VO(2) and VE/VCO(2). CONCLUSIONS: In CHF, overactivation of the ergoreflex is associated with abnormal cardiorespiratory reflex control, independently of clinical severity. Among impaired reflexes, overactivation of the ergoreflex is an important determinant of exercise hyperventilation and reduced exercise tolerance.


Subject(s)
Baroreflex , Chemoreceptor Cells/physiopathology , Energy Metabolism , Heart Failure/physiopathology , Respiration , Autonomic Nervous System/physiopathology , Chronic Disease , Disease Progression , Electrocardiography , Energy Metabolism/physiology , Epinephrine/blood , Exercise Test , Female , Heart Function Tests , Heart Rate , Hemodynamics , Humans , Male , Middle Aged , Muscles/metabolism , Neurons, Afferent , Norepinephrine/blood , Prospective Studies , Regression Analysis , Vascular Resistance
8.
Circulation ; 104(5): 544-9, 2001 Jul 31.
Article in English | MEDLINE | ID: mdl-11479251

ABSTRACT

BACKGROUND: Peripheral chemoreceptor hypersensitivity is a feature of abnormal cardiorespiratory reflex control in chronic heart failure (CHF) and may contribute to sympathetic overactivity, attenuated baroreflex sensitivity (BRS), and excessive ventilation during exercise. We studied whether augmented peripheral chemosensitivity carries independent prognostic significance. METHODS AND RESULTS: We assessed peripheral chemosensitivity (ventilatory response to hypoxia using transient inhalation of pure nitrogen) and BRS (phenylephrine and spectral methods) in 80 consecutive CHF patients (age 58+/-9 years; left ventricular ejection fraction [LVEF] 24+/-12%; peak oxygen consumption [peak VO(2)] 18+/-7 mL(-1). min(-1)). CHF patients demonstrated augmented peripheral chemosensitivity and decreased BRS (all P<0.01 versus reference values). During follow-up (median 41 months, >3 years in all survivors), 37 patients died. High peripheral chemosensitivity (>0.72 L. min(-1). %SaO(2)(-1)) predicted impaired survival (hazard ratio 3.2, 95% CI 1.6 to 6.0, P=0.0006). In the 27 patients (34%) with high peripheral chemosensitivity, 3-year survival was 41% (95% CI 22% to 60%) compared with 77% (66% to 89%) in 53 patients with normal chemosensitivity (P=0.0002). In multivariate analyses, augmented chemosensitivity independently predicted death (hazard ratio 2.8, 95% CI 1.5 to 5.5, adjusted for age, peak VO(2), and VE/VCO(2) [P=0.002]; hazard ratio 2.6, 95% CI 1.3 to 5.1, adjusted for age, LVEF, and peak VO(2) [P=0.008]). Depressed BRS was related to unfavorable prognosis in univariate analysis (P=0.05) but not in multivariate analyses. CONCLUSIONS: Hypersensitivity of the peripheral chemoreceptors independently predicts adverse prognosis in ambulatory patients with CHF. This hyperactive excitatory reflex, through its inhibitory effect on the baroreflex, may be the reason for the previously observed prognostic association of the latter.


Subject(s)
Chemoreceptor Cells/physiopathology , Heart Failure/physiopathology , Aged , Blood Pressure/physiology , Chronic Disease , Exercise Test , Female , Follow-Up Studies , Heart Failure/mortality , Heart Rate/physiology , Humans , Hypoxia/physiopathology , Male , Middle Aged , Multivariate Analysis , Oxygen Consumption , Prognosis , Survival Analysis , Survival Rate
9.
Circulation ; 103(7): 967-72, 2001 Feb 20.
Article in English | MEDLINE | ID: mdl-11181471

ABSTRACT

BACKGROUND: In patients with chronic heart failure (CHF) and preserved exercise tolerance, the value of cardiopulmonary exercise testing for risk stratification is not known. Elevated slope of ventilatory response to exercise (VE/VCO(2)) predicts poor prognosis in advanced CHF. Derangement of cardiopulmonary reflexes may trigger exercise hyperpnea. We assessed the relationship between cardiopulmonary reflexes and VE/VCO(2)and investigated the prognostic value of (VE/VCO(2)) in CHF patients with preserved exercise tolerance. METHODS AND RESULTS: Among 344 consecutive CHF patients, we identified 123 with preserved exercise capacity, defined as a peak oxygen consumption (PEAK VO(2)) >/=18 mL. kg(-1). min(-1) (age 56 years; left ventricular ejection fraction 28%; peak VO(2) 23.5 mL. kg(-1). min(-1)). Hypoxic and hypercapnic chemosensitivity (n=38), heart rate variability (n=34), baroreflex sensitivity (n=20), and ergoreflex activity (n=20) were also assessed. We identified 40 patients (33%) with high VE/VCO(2) (ie, >34.0). During follow-up (49+/-22 months, >3 years in all survivors), 34 patients died (3-year survival 81%). High VE/VCO(2) (hazard ratio 4.3, P<0.0001) but not peak f1.gif" BORDER="0">O(2) (P=0.7) predicted mortality. In patients with high VE/VCO(2), 3-year survival was 57%, compared with 93% in patients with normal VE/VCO(2) P<0.0001). Patients with high VE/VCO(2) demonstrated impaired reflex control, as evidenced by augmented peripheral (P=0.01) and central (P=0.0006) chemosensitivity, depressed low-frequency component of heart rate variability (P<0.0001) and baroreflex sensitivity (P=0.03), and overactive ergoreceptors (P=0.003) compared with patients with normal VE/VCO(2). CONCLUSIONS: In CHF patients with preserved exercise capacity, enhanced ventilatory response to exercise is a simple marker of a widespread derangement of cardiovascular reflex control; it predicts poor prognosis, which VO(2) does not.


Subject(s)
Exercise Tolerance , Heart Failure/physiopathology , Respiratory Function Tests/statistics & numerical data , Ventilation/statistics & numerical data , Chronic Disease , Exercise Test/statistics & numerical data , Follow-Up Studies , Heart Failure/diagnosis , Heart Function Tests/statistics & numerical data , Humans , Middle Aged , Multivariate Analysis , Oxygen Consumption , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Risk Assessment , Survival Rate
10.
Int J Cardiol ; 74(2-3): 215-24, 2000 Jul 31.
Article in English | MEDLINE | ID: mdl-10962124

ABSTRACT

We looked at the benefits and complications of a home-based exercise programme in patients with ischaemic and idiopathic dilated cardiomyopathy. Twenty-four patients with left ventricular end-diastolic dimension >6.5 cm and fractional shortening <25% entered a cross-over trial of 8 weeks training versus 8 weeks rest. Echocardiography, electrocardiogram and cardiopulmonary exercise testing were performed at baseline, after training and after detraining. Training resulted in a higher peak oxygen consumption (26.5 versus 21.3 ml/kg/min, P=0.004), a higher peak heart rate (161 versus 152 bpm, P=0.02) and improved well-being. Patients with idiopathic dilated cardiomyopathy showed a significant increase in exercise time (879 versus 828 s, P=0.03) and peak oxygen consumption (31.3 versus 24.3 ml/kg/min, P=0.02) and a decrease in left ventricular end-diastolic dimension (6.4 versus 6.9 cm, P=0.01) and end-systolic dimension (5.3 versus 5.8 cm, P=0.04) in contrast to those with coronary artery disease, who developed a reduction in septal excursion and shortening rate following training. Complications of training were more common in those patients with ischaemic cardiomyopathy, greater left ventricular dimensions, poorer exercise tolerance and greater ventilation drive at baseline, and included fluid retention and exercise-induced ventricular tachycardia. We found that this group of patients with a dilated, poorly functioning left ventricle can safely derive benefit from a home-based exercise programme, particularly those of idiopathic origin, but they should be closely monitored for the development of complications.


Subject(s)
Cardiomyopathy, Dilated/rehabilitation , Exercise , Myocardial Ischemia/rehabilitation , Adult , Cardiomyopathy, Dilated/diagnosis , Cross-Over Studies , Echocardiography , Electrocardiography , Exercise Test , Exercise Tolerance , Female , Follow-Up Studies , Humans , Male , Middle Aged , Myocardial Ischemia/diagnosis , Oxygen Consumption , Patient Compliance , Probability , Treatment Outcome
11.
Int J Cardiol ; 73(3): 257-65, 2000 May 31.
Article in English | MEDLINE | ID: mdl-10841968

ABSTRACT

We performed a randomised placebo-controlled trial to investigate the effects of the anabolic drug salbutamol on skeletal muscle and exercise capacity in chronic heart failure. Twelve patients received salbutamol slow-release 8 mg twice daily or placebo for 3 weeks. We assessed the effect of treatment on exercise capacity, quadriceps muscle bulk, maximal isometric strength and fatigue, respiratory muscle strength, spirometry and 24-h ECG (electrocardiogram). There was no significant change in the muscle indices, exercise time or peak oxygen consumption. The frequency of ventricular arrhythmias and spirometric measurements were also unchanged. Maximal expiratory mouth pressure, measured at total lung capacity and functional residual capacity, increased significantly (+29.7+/-10.6 vs. -0. 5+/-7.5 cm H(2)O [mean+/-S.E.M., change over 3 weeks treatment salbutamol vs. placebo] and +31.2+/-5.4 vs. +0.2+/-4.0 cm H(2)O both P<0.05). Maximal inspiratory pressures showed a trend towards increasing with treatment when measured from either lung volume (-22. 8+/-9.5 vs. -6.2+/-3.6 cm H(2)O, P=0.14 and -21.5+/-7.5 vs. -3.5+/-3. 4 cm H(2)O, P=0.054). Treatment with 3 weeks of salbutamol increases respiratory muscle strength in chronic heart failure but does not improve quadriceps abnormalities or exercise capacity. Salbutamol is unlikely to have a role in treating the muscle abnormalities in chronic heart failure.


Subject(s)
Albuterol/pharmacology , Bronchodilator Agents/pharmacology , Exercise Tolerance/drug effects , Heart Failure/physiopathology , Albuterol/administration & dosage , Bronchodilator Agents/administration & dosage , Double-Blind Method , Female , Humans , Male , Middle Aged , Respiratory Muscles/drug effects , Respiratory Muscles/physiopathology
12.
Int J Cardiol ; 72(3): 281-6, 2000 Feb 15.
Article in English | MEDLINE | ID: mdl-10716139

ABSTRACT

BACKGROUND: There are limited studies on gender differences in patients with unstable angina. We investigated the influence of gender in these patients in a tertiary referral centre. METHODS AND RESULTS: Three hundred and thirteen consecutive patients (210 men and 103 women) with unstable angina were studied over a 42-month period. Patient characteristics, cardiovascular risk factors and subsequent management including coronary artery bypass graft (CABG) operation and percutaneous transluminal coronary angioplasty (PTCA) were investigated. There was no difference in age [61.6 (11.0) (S.D.) years for men vs. 63.5 (10.5) years for women]. Diabetes mellitus and hypertension were more common in women (diabetes, 11% vs. 23%, P = 0.007; hypertension, 32% vs. 52%; P = 0.001). The number of smokers was greater in men (73% vs. 46%, P = 0.00001). There was no difference in the prevalence of hypercholesterolaemia or in the incidence of previous myocardial infarction, previous history of angina and family history of ischaemic heart disease. The duration of unstable angina before presentation to the referring hospital was similar in both sexes. The use of aspirin, intravenous heparin and antianginal drugs was also comparable in the two genders. The number of coronary arteries involved in men and women appeared similar (one vessel, 22% vs. 27%; two vessels, 26% vs. 21%; three vessels, 52% vs. 52% in men and women, respectively). The proportion of men and women who underwent subsequent revascularisation was also similar (CABG, 31% vs. 33%; PTCA, 42% vs. 40%). The overall in-hospital mortality was higher in women (6.8% vs. 2.8%), but was not statistically significant (P = 0.18). CONCLUSIONS: Gender differences in unstable angina manifest in the preponderance of selected risk factors including diabetes mellitus and hypertension in women and smoking in men. There is no difference in age, the degree of coronary artery involvement and the subsequent management in a tertiary referral centre.


Subject(s)
Angina, Unstable/epidemiology , Coronary Angiography , Diabetes Mellitus/epidemiology , Female , Humans , Hypercholesterolemia/epidemiology , Hypertension/epidemiology , Male , Middle Aged , Retrospective Studies , Risk Factors , Sex Factors , Smoking/epidemiology
13.
Circulation ; 100(24): 2418-24, 1999 Dec 14.
Article in English | MEDLINE | ID: mdl-10595954

ABSTRACT

BACKGROUND: Oscillatory breathing patterns characterized by rises and falls in ventilation with apnea (Cheyne-Stokes respiration [CSR]) or without apnea (periodic breathing [PB]) commonly occur during the daytime in chronic heart failure (CHF). We have prospectively characterized patients with cyclical breathing in terms of clinical characteristics, indices of autonomic control, prognosis, and the role of peripheral chemosensitivity. METHODS AND RESULTS: To determine cyclical breathing pattern, power spectral analysis was applied to 30-minute recordings of respiration in 74 stable CHF patients. Analyses of heart rate variability and baroreflex sensitivity were used to assess autonomic balance. Peripheral chemosensitivity was assessed with the transient hypoxia method. We also determined whether the suppression of peripheral chemoreceptor activity (hyperoxia or dihydrocodeine) would influence the respiratory pattern. Cyclical respiration was found in 49 (66%) patients (22 [30%] CSR, 27 [36%] PB) and was associated with more advanced CHF symptoms, impaired autonomic balance, and increased chemosensitivity (0.80 and 0.75 versus 0.34 L. min(-1). %SaO(2)(-1), P<0.001, for CSR and PB versus normal breathing, respectively). Transient hyperoxia abolished oscillatory breathing in 7 of 8 patients. Dihydrocodeine administration decreased chemosensitivity by 42% (P=0.05), which correlated with improvement in respiratory pattern. Cyclical breathing predicted poor 2-year survival (relative risk 9.41, P<0.01, by Cox proportional hazards analysis), independent of peak oxygen consumption (P=0.04). CONCLUSIONS: An oscillatory breathing pattern during the daytime is a marker of impaired autonomic regulation and poor outcome. Augmented activity of peripheral chemoreceptors may be involved in the genesis of this respiratory pattern. Modulation of peripheral chemosensitivity can reduce or abolish abnormal respiratory patterns and may be an option in the management of CHF patients with oscillatory breathing.


Subject(s)
Cheyne-Stokes Respiration/physiopathology , Heart Failure/physiopathology , Pressoreceptors/physiology , Aged , Analgesics, Opioid/administration & dosage , Autonomic Nervous System/physiology , Chronic Disease , Codeine/administration & dosage , Codeine/analogs & derivatives , Female , Follow-Up Studies , Heart Rate , Humans , Male , Middle Aged , Oxygen/administration & dosage , Oxygen Consumption , Periodicity , Postural Balance , Pressoreceptors/drug effects , Prognosis , Prospective Studies , Respiratory Mechanics/drug effects , Respiratory Mechanics/physiology , Wakefulness
14.
Eur Heart J ; 20(22): 1667-75, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10543930

ABSTRACT

BACKGROUND: The mechanism of persistent neurohormonal and cardiorespiratory reflex abnormalities in chronic heart failure remain unclear. Also, why chronic heart failure patients who develop cachexia demonstrate a particularly abnormal neurohormonal profile and have a high risk of death is not known. Impaired reflex control within the cardiac and respiratory systems, and abnormal heart rate variability have both been linked to a poor outcome. Muscle reflexes may contribute to persistent neurohormonal overactivity in wasted patients. Thus, we hypothesized that patients with cardiac cachexia might exhibit particularly profound abnormalities in cardiorespiratory reflexes and heart ratevariability. METHODS AND RESULTS: We investigated 39 chronic heart failure patients: 13 with cardiac cachexia (non-intentional, non-oedematous, documented weight loss of >7.5% of previous normal weight over more than 6 months), and 26 non-cachectic chronic heart failure patients matched according to the severity of chronic heart failure (all men, mean age: 59 vs 60 years, NYHA functional class: 2.6 vs 2.5, peak O(2)consumption: 16.2 vs 16.8 ml. kg(-1). min(-1), left ventricular ejection fraction: 23 vs 24%, all P>0.2 for cachectic vs non-cachectic). In the assessment of the cardiorespiratory reflex control we investigated: cardiac sympathovagal balance (using spectral analysis of heart rate variability to derive low (LF, 0. 04-0.15Hz) and high frequency (HF, 0.15-0.4Hz) components), baroreflex sensitivity (using the phenylephrine method), and peripheral chemosensitivity (using the transient hypoxic method). There was a severely abnormal pattern of cardiorespiratory reflex control in patients with cachexia compared with non-cachectic patients. The former group exhibited severely impaired autonomic reflex control, characterized by an abnormal profile of heart rate variability (reduced LF component), and depressed baroreflex sensitivity (P=0.0001 and P=0.02, respectively, vs non-cachectics). Patients with cachexia also demonstrated an increased peripheral chemosensitivity (0.91 vs0.46 l. min(-1). %SaO(2)(-1), P<0.001, cachectic vs non-cachectic, respectively). In the correlation analyses the degree of impairment in the reflex control was more closely related to wasting, and to the level of neurohormonal activation (as measured by the levels of epinephrine and norepinephrine) than to conventional markers of the severity of heart failure. CONCLUSIONS: Chronic heart failure patients who developed cardiac cachexia demonstrate an abnormal reflex control within the cardiovascular and respiratory systems. The nature of the link between this phenomenon and hormonal changes and the poor prognosis of cachectic chronic heart failure patients warrants further investigation.


Subject(s)
Cachexia/physiopathology , Heart Failure/physiopathology , Heart Rate/physiology , Pulmonary Ventilation/physiology , Reflex/physiology , Cachexia/mortality , Chemoreceptor Cells/physiopathology , Heart Failure/mortality , Humans , Male , Middle Aged , Neurotransmitter Agents/physiology , Pressoreceptors/physiopathology , Prognosis , Reflex, Abnormal/physiology , Survival Rate
15.
Heart ; 82(3): 348-51, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10455087

ABSTRACT

OBJECTIVE: To explore whether the anaerobic threshold, a measure of the balance between aerobic and anaerobic cellular metabolism, is related to whole body insulin sensitivity in healthy individuals and in patients with chronic heart failure, which involves is an imbalance of aerobic and anaerobic metabolism. DESIGN: Case-control study. SETTING: A teaching hospital department specialising in heart failure. PATIENTS: 20 healthy individuals (mean (SEM) age 55.2 (2.7) years) and 36 patients with chronic heart failure (59.1 (2.0) years, New York Heart Association class I-IV, anaerobic threshold 11.8 (0. 7) ml/kg/min, left ventricular ejection fraction 26 (2)%). INTERVENTIONS: An intravenous glucose tolerance test for assessment of insulin sensitivity (minimal model analysis) and a maximum treadmill exercise test for assessment of the anaerobic threshold, derived from measurement of oxygen consumption and carbon dioxide output. MAIN OUTCOME MEASURES: Relation between insulin sensitivity and the anaerobic threshold in patients with chronic heart failure. RESULTS: While anaerobic threshold was positively correlated with insulin sensitivity in healthy controls (r = 0.72, p < 0.001), no such relation was observed in patients with chronic heart failure. In stepwise multiple linear regression analyses of variables in healthy individuals, insulin sensitivity emerged as the only predictor of anaerobic threshold (standardised coefficient = 0.72, p < 0.001), while fasting insulin, incremental insulin area, and total body fat (dual photon x ray absorptiometry) failed to enter into final models (joint R = 0.52, p < 0.001). CONCLUSIONS: In healthy individuals, whole body insulin sensitivity is related, or "coupled, " to the anaerobic threshold. The absence of such metabolic coupling in patients with chronic heart failure provides further evidence of disturbed cellular metabolism in patients with this condition.


Subject(s)
Anaerobic Threshold/physiology , Heart Failure/physiopathology , Insulin Resistance/physiology , Aged , Analysis of Variance , Case-Control Studies , Exercise Test , Glucose Tolerance Test , Humans , Middle Aged
16.
Int J Cardiol ; 66(1): 55-8, 1998 Sep 01.
Article in English | MEDLINE | ID: mdl-9781788

ABSTRACT

We report the successful long-term use of an implantable left ventricular assist device in a 42-year old patient who suffered cardiogenic shock after an acute anterior myocardial infarction unresponsive to recanalisation of the infarct-related artery and intra-aortic balloon counterpulsation. Attempts to wean our patient from the assist device were not successful and the patient underwent cardiac transplantation after 35 weeks on device assistance. The intermediate and long-term use of an implantable left ventricular assist device may be lifesaving in post-myocardial infarction cardiogenic shock and may allow sufficient time for any stunned myocardium to recover. Should there be no recovery, the device acts as a bridge to cardiac transplantation.


Subject(s)
Heart-Assist Devices , Myocardial Infarction/complications , Shock, Cardiogenic/therapy , Adult , Female , Heart Transplantation , Humans , Intra-Aortic Balloon Pumping , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/therapy , Shock, Cardiogenic/diagnostic imaging , Shock, Cardiogenic/etiology , Treatment Failure , Ultrasonography
17.
Metabolism ; 47(9): 1156-9, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9751248

ABSTRACT

The anaerobic threshold (AT) is a measure of the balance between aerobic and anaerobic cellular metabolism. Hyperuricemia occurs in conditions that involve an imbalance between cellular oxygen consumption and carbon dioxide production, such as chronic heart failure (CHF). We therefore hypothesized that in CHF, serum uric acid might be related to the AT. Patients with CHF (n=40, aged 58.7+/-1.9 years; New York Heart Association Class I-IV; maximal oxygen consumption [MVO2], 18.7+/-01.1 mL/kg/min; left ventricular ejection fraction, 26%+/-2%) and 10 age-matched healthy controls underwent measurement of the serum uric acid level at rest and assessment of the AT. This was derived from MVO2 and the regression slope relating minute ventilation to carbon dioxide output (VE - VCO2) during a maximal treadmill exercise test. Compared with the healthy controls, patients with CHF had a lower AT (11.8+/-0.7 v 16.9+/-1.1 mL/kg/min, P < .001) and a higher serum uric acid concentration (493.8+/-22.4 v 308.7+/-21.5 micromol/L, P < .001). In univariate analyses of the CHF group, the AT correlated with serum uric acid (r=-.56, P < .001; AT=19.93 - (0.016 x uric acid), R2=.31, P < .001) and plasma creatinine (r=-.43, P < .01), but not with the diuretic dose. In stepwise regression analyses of the CHF group, serum uric acid emerged as a predictor of the AT (standardized coefficient=-.56, P < .001), whereas the diuretic dose and plasma creatinine failed to enter into the final models (multiple R2=.31, P < .001). In conclusion, in CHF there is an inverse relationship between the AT and the resting serum uric acid concentration. This is consistent with the known links between uric acid production and the imbalance in aerobic/anaerobic metabolism that occur in CHF. These findings provide the basis for using the simple measurement of the serum uric acid level as a surrogate measure of the AT.


Subject(s)
Heart Failure/metabolism , Uric Acid/blood , Anaerobiosis , Blood Pressure , Chronic Disease , Humans , Middle Aged , Multivariate Analysis
18.
Am J Cardiol ; 82(3): 338-44, 1998 Aug 01.
Article in English | MEDLINE | ID: mdl-9708664

ABSTRACT

In chronic congestive heart failure (CHF) an overactivity of muscle ergoreceptors and peripheral chemoreceptors may lead to an increased ventilatory response to exercise and contribute to the autonomic imbalance. The analysis of heart rate variability (HRV), which is a reliable method of studying autonomic regulations within the cardiovascular system, showed depressed HRV indexes in CHF, but predictors of abnormal HRV pattern in CHF remain controversial. Considering a common mechanism involved in generation of both abnormal ventilation and autonomic dysfunction in CHF, we hypothesized that impaired ventilation may be better than other variables of CHF severity in determining HRV parameters. Seventy-two patients with CHF (57+/-9 years, ejection fraction: 28+/-11%) underwent cardiopulmonary exercise testing; the relation between ventilation and carbon dioxide production (VE/VCO2) was used as an index of the ventilatory response to exercise. Time and frequency-domain measurements of HRV were derived from 24-hour electrocardiographic monitoring. Patients had reduced exercise tolerance with abnormal ventilatory response (peak oxygen consumption [VO2max]: 17.8+/-5.5 ml/kg/min, VE/VCO2: 36.0+/-9.8). Correlations were found between HRV measures and etiology, New York Heart Association (NYHA) functional class, and VO2max, but the strongest relation was observed for VE/VCO2 slope (r values from -0.33 to -0.65, p <0.01). In the multiple regression analysis only VE/VCO2 was found to correlate independently with all HRV measurements. To investigate the role of peripheral chemoreceptor overactivity as the mechanism of autonomic imbalance and the increased ventilatory response to exercise, we assessed peripheral chemosensitivity in 22 patients (mean value of peripheral chemosensitivity: 0.62+/-0.34 L/min/%SaO2, significantly higher than in normal controls, mean value: 0.29+/-0.20 L/min/%SaO2 in our laboratory). The activity of the peripheral chemoreflex inversely correlated with all parameters of HRV. Increased ventilatory response to exercise correlated with depressed HRV measures in patients with CHF better than other clinical variables. An important role of the increased peripheral chemosensitivity in this relation may be relevant, being also a potential link between functional severity and sympathovagal imbalance in CHF.


Subject(s)
Exercise/physiology , Heart Failure/physiopathology , Heart Rate/physiology , Respiration/physiology , Administration, Inhalation , Autonomic Nervous System/physiopathology , Chemoreceptor Cells/physiopathology , Chronic Disease , Electrocardiography, Ambulatory , Female , Humans , Male , Middle Aged , Multivariate Analysis , Nitrogen/administration & dosage , Predictive Value of Tests , Respiratory Function Tests
19.
Int J Cardiol ; 63(3): 245-50, 1998 Feb 28.
Article in English | MEDLINE | ID: mdl-9578351

ABSTRACT

OBJECTIVE: To audit the practice of ultrasound-guided compression of femoral pseudoaneurysm in a specialist cardiac hospital. BACKGROUND: Femoral pseudoaneurysm is an important complication of invasive cardiac procedures. This may require surgical repair but more recently ultrasound-guided compression for ablating pseudoaneurysms has been described. We investigated the success of such a procedure. METHODS AND RESULTS: In a 26-month period, 56 patients were referred for ultrasound scanning to exclude the formation of a femoral pseudoaneurysm following transfemoral cardiac procedures. During this period, 5756 diagnostic cardiac catherisations and 1165 coronary angioplasties were performed in our hospital (total of 6921 procedures). Of the 56 patients, 20 patients (0.3% of 6921) were found to have a pseudoaneurysm. Ultrasound-guided compression was attempted in 11 patients and was successful in 7 patients (64%). Of the patients who had failed ultrasound-guided compression, 2 proceeded to surgical closure and 2 were treated conservatively with compression stockings to facilitate thrombosis of the pseudoaneurysm. Of those who did not have an attempted ultrasound-guided compression of the pseudoaneurysm (n=9), a conservative approach consisting of resting the leg was adopted to facilitate spontaneous thrombosis of the pseudoaneurysm; repeat ultrasound scanning was needed for follow-up and 1 patient required surgical closure in this group. CONCLUSIONS: In patients with a femoral pseudoaneurysm following an invasive cardiac procedure, ultrasound-guided compression may be useful as an immediate step to ablate the pseudoaneurysm. This avoids either prolonged leg rest and repeated ultrasound scanning or surgical intervention. However, ultrasound-guided compression is not always successful; in these patients, a period of conservative management with repeat ultrasound scanning is appropriate to allow for the possible spontaneous thrombosis of the pseudoaneurysm. Surgical closure is needed in those patients whose pseudoaneurysm is enlarging, painful or remain patent.


Subject(s)
Aneurysm, False/diagnostic imaging , Aneurysm, False/surgery , Femoral Artery , Adult , Aged , Aged, 80 and over , Aneurysm, False/etiology , Angioplasty, Balloon, Coronary/adverse effects , Cardiac Catheterization/adverse effects , Female , Humans , Male , Medical Audit , Middle Aged , Treatment Outcome , Ultrasonography
20.
Int J Cardiol ; 67(3): 247-9, 1998 Dec 31.
Article in English | MEDLINE | ID: mdl-9894706

ABSTRACT

There are clear benefits in treating hypercholesterolaemia in patients with ischaemic heart disease, especially those with previous myocardial infarction. Following publication of trial evidence and treatment guidelines for hypercholesterolaemia, we investigated the current practice of the management of hypercholesterolaemia in patients with coronary artery disease referred for coronary angiography by general physicians. We prospectively reviewed 156 consecutive patients (117 men; mean age 61.5+/-9.6 [S.D.] years) with a history of angina pectoris who attended the day case unit for coronary angiography in a 10 week period. Nearly a tenth of these patients had not been screened for hypercholesterolaemia in this study. Of those patients with a cholesterol level > or =5.5 mmol/l, almost a quarter were not on a statin or any other cholesterol-lowering therapy. Continued effort should be given to the screening and effective management of hypercholesterolaemia in patients with coronary artery disease.


Subject(s)
Coronary Disease/complications , Hypercholesterolemia/drug therapy , Aged , Anticholesteremic Agents/therapeutic use , Cholesterol/blood , Cohort Studies , Coronary Angiography , Coronary Disease/diagnostic imaging , Data Interpretation, Statistical , Diabetes Complications , Female , Follow-Up Studies , Humans , Hypercholesterolemia/complications , Hypertension/complications , Male , Middle Aged , Pravastatin/therapeutic use , Risk Factors , Simvastatin/therapeutic use , Smoking , Treatment Outcome
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