Aneurysms and pseudoaneurysms of saphenous vein coronary artery bypass grafts

Aneurysms of saphenous vein grafts to coronary arteries are unusual complications of coronary artery bypass graft (CABG) surgery. Three patients (men aged 47, 62, and 68 years) are presented with spontaneous chest pains 10, 21, and 17 years after CABG surgery. In one case, the saphenous vein graft had eroded into the right atrium and had established a fistula between the graft and the right atrium. Diagnosis of saphenous vein graft aneurysms was confirmed by echocardiography, computed tomography or magnetic resonance imaging, and by arteriography. Two patients were treated surgically, the third by percutaneous coil embolisation followed by balloon angioplasty of the right coronary artery.

Keywords: aneurysm;  pseudoaneurysm;  saphenous vein grafts;  coronary artery bypass graft     

Long term results of reoperations for recurrent angina with internal mammary artery versus saphenous vein grafts

Objective—To evaluate the long term results of coronary reoperations for recurrent angina with internal mammary (thoracic) arteries versus vein grafts.
Design—Inception cohort of 103 patients with a mean follow up of 7.1 years (range 1.0-11.6).
Setting—Regional cardiothoracic centre.
Patients—Among 103 consecutive patients, mean (SD) age 61.8 (9.7) years, who were reoperated for recurrent angina between January 1982 and December 1991, 53 patients had unilateral or bilateral internal mammary artery (IMA) grafting supplemented or not with saphenous vein (SV) grafts (group A), and 50 patients underwent reoperative coronary surgery using SV grafts only (group B). The two groups were comparable in terms of demographic and clinicopathological data.
Measurements and results—Operative mortality was 5.6% (95% confidence interval 4.6 to 6.6) for group A, and 10% (8.2 to 11.8) for group B (p > 0.05). Probability of freedom from new recurrence of angina was 86% at 5 and 10 years in group A, compared with 56% and 25% respectively in group B (p = 0.005). Freedom from cardiac events was estimated to be 81% at 5 and 10 years in group A, v 52% and 20% for group B, respectively. Actuarial survival was 95% v 93% at 3 years, 95% v 85% at 5 years, and 88% v 71% at 10 years after reoperation (p > 0.05).
Conclusions—The long term results of IMA are superior to SV grafts in terms of freedom from new recurrence of angina and other cardiac events. The IMA is thus the conduit of choice in coronary revascularisation.

Keywords: coronary artery bypass;  coronary reoperation;  recurrent angina;  internal thoracic (mammary) artery     

Ten year follow up of patients referred for coronary artery bypass grafting from a single district general hospital

Objective—To determine the status of patients 10 years after referral for coronary artery bypass graft (CABG) surgery.
Design—Retrospective analysis of case notes from all patients referred between 1 April 1981 and 31 March 1985. Full information gathered from hospital notes, GP records, and Registrar General for Scotland.
Setting—District General Hospital, West Lothian, Scotland.
Patients—102 patients referred for CABG during study period. Cardiac surgery was undertaken in Brompton Hospital, London, Royal Infirmary, Edinburgh, and Western Infirmary, Glasgow.
Results—At 10 years after operation 32 patients had died (27 cardiac, five non-cardiac causes). Full data were not available for five patients. Of the 65 remaining patients 24 had no angina, 13 had had a repeat procedure (CABG or angioplasty), and 28 had angina.
Conclusions—Long term benefits of CABG surgery is disappointing. Further steps are required to reduce progression of disease in this population.

Keywords: coronary artery bypass surgery;  repeat procedure;  survival;  audit     

Endoluminal vessel reconstruction by stent placement in patients with obstructive coronary artery disease who are poor surgical candidates

Objective—To investigate the safety and efficacy of endoluminal vessel reconstruction by intracoronary stenting in patients with single or multivessel disease who have been turned down for surgical revascularisation.
Design—An observational, single centre trial of consecutive patients being followed up clinically.
Setting—Tertiary referral centre.
Patients—43 patients treated between 1995 and 1996 with a clinical follow up period of at least six months.
Main outcome measures—Acute procedural success following intervention (defined as a residual stenosis of < 30% with normal antegrade flow and without acute clinical complications); major adverse clinical events (death, myocardial infarction, repeat intervention, clinical restenosis); and functional status during follow up.
Results—Acute procedural success was achieved in 39 patients. Failures resulted from a refractory no reflow phenomenon with Q wave myocardial infarction (two patients), and from subacute stent thrombosis (one patient) and saphenous vein graft rupture at stent site (one patient), both manifesting by non-Q wave myocardial infarction. During a follow up period of 17 (8) months (mean (SD)), three of these patients died. Clinical restenosis was treated by repeat percutaneous intervention in 11 patients, while 28 patients remained asymptomatic. On a Kaplan-Meier estimate, the proportion of patients without adverse clinical events at two years was 65%.
Conclusions—Percutaneous reconstruction of diseased coronary arteries in patients with single or multivessel disease turned down for surgical revascularisation may be considered as a valuable treatment option. On follow up, more events seem to be encountered than after elective de novo stenting of discrete coronary lesions. This is probably related to higher clinical restenosis rates.

Keywords: coronary artery disease;  stents;  restenosis     

Platelet aggregation and incident ischaemic heart disease in the Caerphilly cohort

BACKGROUND: Platelets are involved in myocardial infarction but evidence of prediction of infarction by measures of platelet function are sparce. METHODS: Platelet aggregation to thrombin and to ADP in platelet rich plasma was recorded for 2176 men aged 49-65 years in the Caerphilly cohort study. RESULTS: Results from 364 men were excluded, 80 of whom had not fasted before venepuncture; most of the others were excluded because antiplatelet medication had been taken shortly before the platelet tests. During the five years following the platelet tests 113 ischaemic heart disease (IHD) events which fulfilled the World Health Organisation criteria were identified--42 fatal and 71 non-fatal. No measure of platelet aggregation was found to be significantly predictive of incident IHD. The possibility that platelet function is predictive for only a limited time after it is characterised, and that prediction falls off with time, was tested. When IHD events are grouped by their time of occurrence after aggregation had been measured, the test results show a gradient suggestive of prediction of early IHD events. Thus, 24% of the men who had an event within 500 days of the test had had a high secondary response to ADP while only 12% of those whose IHD event had been 1000 or more days after the test had shown a high platelet response at baseline. The trend in these proportions is not significant. CONCLUSIONS: Platelet aggregation to thrombin and ADP in platelet rich plasma was recorded in the Caerphilly cohort study. No measure of aggregation was found to be predictive of IHD.     

Restenosis after elective coronary balloon angioplasty in patients with end stage renal disease: a case-control study using quantitative coronary angiography

Objective—To assess the rate of angiographic restenosis in patients with end stage renal disease after elective coronary angioplasty.
Design—A retrospective case-control study of 20 patients with end stage renal disease and 20 sex and age matched controls without renal disease, who had undergone primarily successful coronary angioplasty. Control coronary angiography was performed regardless of worsening or renewed incidence of anginal symptoms.
Main outcome measures—Group comparison of coronary morphology, as evaluated by quantitative coronary angiography, and of cardiovascular risk factors.
Results—The rate of angiographic restenosis was 60% in patients with renal disease and 35% in controls. In patients with end stage renal disease the following differences (mean (SD) were found versus controls: raised plasma fibrinogen (483 (101) v 326 (62) mg/dl, p < 0.001); raised plasma triglyceride (269 (163) v 207 (176) mg/dl, p < 0.01); smaller diameter of the coronary reference segment (2.59 (0.87) v 2.90 (0.55) mm, p < 0.10); smaller minimum luminal diameter of the dilated stenosis (0.77 (0.46) v 0.97 (0.27) mm, p < 0.05). Discriminant analysis showed that minimum luminal diameter before angioplasty (r = −0.79) and fibrinogen (r = +0.34) had the highest statistical association with restenosis.
Conclusions—The high rate of angiographic restenosis in patients with end stage renal disease seems to be related to the size of the vessel dilated and to an increased prothrombotic risk, as indicated by higher fibrinogen concentrations.

Keywords: renal disease;  coronary artery disease;  coronary angioplasty;  restenosis     

Brachial approach directional coronary atherectomy of a left coronary artery saphenous vein bypass graft

Directional coronary atherectomy (DCA) of a saphenous vein bypass graft to the left coronary artery was performed percutaneously from the brachial artery approach using a 7F endomyocardial biopsy sheath. Initial positioning was accomplished with a left bypass graft catheter inserted in the sheath. This technique permits use of smaller catheters than usual for DCA in patients in whom larger guides cannot be used. © 1993 Wiiey-Liss, Inc.     

Bradykinin induced dilatation of human epicardial and resistance coronary arteries in vivo: effect of inhibition of nitric oxide synthesis

Objective—To clarify whether endothelium derived nitric oxide contributes to exogenous bradykinin induced dilatation of human epicardial and resistance coronary arteries in vivo.
Design—Quantitative coronary angiography and Doppler flow velocity measurements were used to determine the effects of the nitric oxide synthesis inhibitor, N^G-monomethyl-L-arginine (L-NMMA), on bradykinin induced dilatation of the epicardial and resistance coronary arteries.
Setting—Hiroshima University Hospital.
Patients—20 patients (16 men and four women, mean (SD) age 56 (9) years) with angiographically normal smooth epicardial coronary arteries.
Interventions—Serial infusions of bradykinin (0.5, 1.5, and 2.5 µg/min) were given into the left coronary ostium before and after L-NMMA infusion (60 µmol/min).
Main outcome measures—Epicardial coronary diameter, coronary blood flow, and coronary vascular resistance.
Results—Bradykinin-induced epicardial coronary vasodilatation after L-NMMA (dilatation by 2.5 µg/min, 3.8(1.4)% in the proximal and 5.9(1.8)% in the distal segments, mean (SEM)) was less (p < 0.001, respectively) than before L-NMMA (11.7(2.5)% and 15.1(2.0)%, respectively). In contrast, L-NMMA did not affect the bradykinin induced increase in coronary blood flow and decrease in coronary vascular resistance.
Conclusions—Endothelium derived nitric oxide contributes to bradykinin induced dilatation of epicardial coronary arteries, but may be less important in coronary resistance vasodilatation.

Keywords: bradykinin;  nitric oxide;  coronary artery;  coronary blood flow     

冠状动脉严重病变的高龄患者的非体外循环冠状动脉旁路移植术

目的　总结冠状动脉严重病变的高龄患者行非体外循环冠状动脉旁路移植术 (OPCAB)的治疗经验。方法　回顾性分析 5 3例 ,年龄在 75～ 82 (77± 2 )岁 ,冠状动脉严重病变的患者行OPCAB的临床资料。 3支病变 4 4例 ,左主干病变 2 1例 ,前降支近端 90 %～ 10 0 %狭窄 2 5例 ,右冠状动脉近端 90 %～ 10 0 %狭窄 17例 ,急诊冠状动脉旁路移植术 13例。 5 3例OPCAB手术全部成功。平均远端吻合口数目 (3.0± 0 .8)个 ,移植物取乳内动脉 2 9例 ,大隐静脉 5 1例。结果　术后并发症 4例 :其中新发脑卒中 1例 ,2次开胸止血 1例 ,恶性心律失常 1例 ,多脏器功能衰竭 1例 ;主动脉内球囊反搏 7例 ;住院死亡 2例。随访时间 1～ 2 4 (10± 7)个月 ,均无急性心血管事件发生 ,非心脏性死亡 1例。结论　OPCAB对冠状动脉严重病变的高龄患者是安全可行而且有效的血运重建方式     

Coronary flow reserve in the contralateral artery increases after successful coronary angioplasty in patients with spontaneously visible collateral vessels

Objective—To test the hypothesis that coronary flow reserve could increase in the angiographically normal contralateral artery after successful coronary angioplasty of an ipsilateral coronary artery.
Design—Coronary flow reserve was estimated using a Doppler flow guide wire, by giving intracoronary adenosine in the contralateral artery, before and 15 minutes after the end of angioplasty.
Setting—Tertiary referral centre.
Patients—31 patients, mean (SD) age 56 (11) years, with stable angina and single vessel disease, undergoing angioplasty of the right coronary or the left anterior descending artery.
Results—In the contralateral artery baseline average peak velocity was 21 (9) cm/s before angioplasty and decreased to 12 (6) cm/s after (p < 0.005), while hyperaemic average peak velocity was 47 (19) cm/s before and decreased to 34 (15) cm/s after (p < 0.005). However, coronary flow reserve in the contralateral artery was 2.4 (0.7) before angioplasty and increased to 2.9 (0.6) after (p < 0.05). The contralateral coronary flow reserve after angioplasty increased by 0.8 (0.4) in 11 patients with visible collaterals before angioplasty and by 0.3 (0.6) in the remaining patients without visible collaterals (p < 0.05). Blood pressure and heart rate were unchanged after the procedure.
Conclusions—Coronary flow reserve in an angiographically normal contralateral artery increases after successful coronary angioplasty of the ipsilateral artery in patients with spontaneously visible collateral vessels before the procedure.

Keywords: coronary flow reserve; contralateral coronary artery; angioplasty     

Hibernating myocardium caused by isolated, radiation induced left main stem coronary artery stenosis

A 45 year old man presented with a five week history of worsening exertional dyspnoea and orthopnoea. He had also noted mild, bilateral ankle swelling. The patient had been diagnosed with stage III Hodgkin's lymphoma in 1968 at the age of 21. During the same year he underwent total nodal irradiation followed by chemotherapy in 1971. He had remained entirely asymptomatic over the course of the next 24 years with no evidence of relapse. Cardiac catheterisation undertaken soon after admission revealed a tight left main stem stenosis with a left dominant system. Left ventriculogram showed severe, global hypokinesia, and raised left ventricular end diastolic pressure (22 mm Hg). Urgent coronary artery bypass graft surgery was carried out. He made an uncomplicated recovery and his condition improved sufficiently to allow discharge eight days following the procedure. His heart failure slowly resolved and repeat transthoracic echocardiogram performed six months after surgery showed an unequivocal improvement in left ventricular function. Left ventricular ejection fraction continued to improve and increased from 23% at two months to 42% at two years. He currently remains entirely asymptomatic off all medication.

Keywords: left main stem stenosis;  radiation induced coronary artery disease;  hibernating myocardium     

Tyrosine phosphorylation of platelet derived growth factor β receptors in coronary artery lesions: implications for vascular remodelling after directional coronary atherectomy and unstable angina pectoris

Background—Growth factors such as platelet derived growth factor (PDGF) have been postulated to be important mediators of neointimal proliferation observed in atherosclerotic plaques and restenotic lesions following coronary interventions. Binding of PDGF to its receptor results in intrinsic receptor tyrosine kinase activation and subsequent cellular migration, proliferation, and vascular contraction.
Aims—To investigate whether the concentration of PDGF β receptor tyrosine phosphorylation obtained from directional coronary atherectomy (DCA) samples correlate with atherosclerotic plaque burden, the ability of diseased vessels to remodel, coronary risk factors, and clinical events.
Methods—DCA samples from 59 patients and 15 non-atherosclerotic left internal thoracic arteries (LITA) were analysed for PDGF β receptor tyrosine phosphorylation content by receptor immunoprecipitation and antiphosphotyrosine western blot. The amount of PDGF β receptor phosphorylation was analysed in relation to angiographic follow up data and clinical variables.
Results—PDGF β receptor tyrosine phosphorylation in the 59 DCA samples was greater than in the 15 non-atherosclerotic LITA (mean (SD) 0.84 (0.67) v 0.17 (0.08) over a control standard, p < 0.0001). As evaluated by stepwise regression analysis, incorporation of both PDGF β receptor tyrosine phosphorylation and immediate gain correlated strongly (adjusted r² = 0.579) with late loss, although PDGF β receptor tyramine phosphorylation alone correlated poorly with late loss. Multivariate regression analysis of coronary risk factors and clinical events revealed unstable angina as the most significant correlate of PDGF β receptor tyrosine phosphorylation (F value 20.009, p < 0.0001).
Conclusions—PDGF β receptor tyrosine phosphorylation in atherosclerotic lesions is increased compared with non-atherosclerotic arterial tissues. The association of PDGF β receptor tyrosine phosphorylation with immediate gain strongly correlates with vascular remodelling. PDGF β receptor tyrosine phosphorylation correlates with unstable angina pectoris.

Keywords: PDGF receptors;  atherosclerosis;  directional coronary atherectomy;  restenosis     

The falling mortality from coronary heart disease: a clinicopathological perspective

Objective—(1) To compare mortality estimates based on clinicopathological diagnoses of death from acute coronary heart disease with official estimates of coronary heart disease mortality; (2) to compare present day mortality figures with those from earlier reports.
Design—Prospective community study over the two years 1994 and 1995.
Setting—The health districts of Brighton, South Glamorgan, and York.
Subjects—1589 men and women under 75 years of age who, based on our study criteria, died from acute coronary events were compared with certified cases of coronary death in the same age group.
Main outcome measures—(1) Comparison of the underlying cause recorded on death certificates with the diagnosis of acute coronary death defined by our study criteria; (2) comparison of age specific mortality figures of the present with earlier studies.
Results—Up to age 65, age specific mortality for coronary heart disease, using study criteria, was similar to official estimates. However, at ages 65-74 years there was a shortfall in study deaths of about 20% compared with official figures. One reason for this was that many death certificates in elderly people attributed death to coronary disease in the absence of confirmatory evidence. Despite this, deaths in the under 65 age group in the 1990s appear to be occurring in people who are about 10 years older than was the case during the 1970s.
Conclusions—There are differences, most noticeable in elderly subjects, between estimates of coronary mortality made according to strict clinical and pathological definitions and official rates based on death certification. Recognition of these differences will be important for future epidemiological studies.

Keywords: mortality;  coronary heart disease;  clinicopathological diagnosis;  epidemiology     

Right ventricular dysfunction during coronary artery occlusion: pressure-volume analysis using conductance catheters during coronary angioplasty

Objective—To study the effects of coronary artery occlusion on the pressure-volume relations of the right ventricle.
Design—Right ventricular pressure-volume cycles were studied using conductance catheters and micromanometers in 19 subjects undergoing coronary angioplasty in a tertiary referral cardiac centre.
Results—Catheter occlusions of either the left anterior descending coronary artery or the right coronary artery were associated with a decline in stroke work (mean change (SD): left −13.3(15.8)%, p = 0.008; right −13.5(16.5)%, p = 0.04). Two patterns of change were evident: an upward shift usually associated with occlusion in the left coronary artery, and a rightward shift in the right coronary artery. In the former there was an increase in maximum ventricular volume (mean change: 3.0(2.7)%, p = 0.004) and in minimum ventricular volume (mean change: 2.3(2.7)%, p = 0.01) and a fall in peak pressure (mean change: −4.8(5.1)%, p = 0.04). In the latter there was an increase in peak pressure (mean change 9.9(16.3)%, p = 0.04) and an increase in minimum ventricular volume (mean change 3.7(5.0)%, p = 0.02) leading to a fall in stroke volume (mean change −13.3(15.8)%, p = 0.008).
Conclusions—Occlusion of the left anterior descending coronary artery or the right coronary artery is associated with a decline in right ventricular work. However, different patterns of change in indices of preload and afterload lead to different effects on overall right ventricular pump function.

Keywords: right ventricle;  pressure-volume relations;  coronary angioplasty;  conductance catheter     

Changes in pulmonary artery size before and after total cavopulmonary connection

Objective—To assess changes in size of the central pulmonary arteries following a total cavopulmonary connection (TCPC).
Design—A retrospective analysis of the angiographic diameters of the central pulmonary arteries, expressed as z scores, in infancy before the TCPC and 3.5 (0.9) years (mean (SD)) later. Analysis of the relation between the pulmonary arteriolar resistance and the z scores at follow up.
Setting—Tertiary referral centre.
Patients—32 patients who had TCPC from February 1990 to July 1993.
Results—The patients were divided into two groups (n = 16) depending on their preoperative flow ratio: group I, Qp/Qs  1; group II, Qp/Qs > 1. At the initial study in infancy the mean z scores in group I were −6.0 for the right pulmonary artery (RPA) and −9.6 for the left pulmonary artery (LPA); in group II the respective values were −2.7 and −3.0. Before the TCPC the values increased to 0.5 (RPA) and −0.5 (LPA) in group I, and to 8.8 (RPA) and 8.2 (LPA) in group II. At follow up the z scores decreased to −2.4 (RPA) and −4.9 (LPA) in group I, and to 2.2 (RPA) and −0.7 (LPA) in group II. The changes in pulmonary artery diameters were significant for both groups (p < 0.02). Following the TCPC, no significant difference in pulmonary arteriolar resistance index was found between patients with relatively small pulmonary arteries (z score RPA+LPA  0) and those with relatively large pulmonary arteries (z score RPA+LPA > 0).
Conclusions—Creation of a TCPC results in a significant reduction in size of the central pulmonary arteries. At a mean interval of 3.5 years following the TCPC, however, there was no significant difference in pulmonary arteriolar resistance index between patients with smaller and larger central pulmonary arteries.

Keywords: total cavopulmonary connection;  congenital heart disease;  pulmonary artery size;  pulmonary arteriolar resistance     

Myocardial ischaemia in a case of a solitary coronary ostium in the right aortic sinus with retroaortic course of the left coronary artery: documentation of the underlying pathophysiological mechanisms of ischaemia by intracoronary Doppler and pressure measurements

Only a few cases of a single coronary ostium and retroaortic course of the coronary artery have been described. Almost all cases reported so far had additional coronary artery or valvar disease. However, myocardial ischaemia may be caused by the coronary malformation alone. A 40 year old woman with severe myocardial ischaemia in the absence of clinically relevant coronary atherosclerosis is described. To clarify the origin and mechanisms of ischaemia, intracoronary Doppler, pressure and ultrasound studies were performed using microtransducers. In its outer portion along the course behind the ascending aorta, coronary blood flow velocities were increased, there was an external elliptical compression, and distal coronary flow reserve was reduced. Furthermore, an overshoot in diastolic pressure above aortic pressure was detectable within this portion. Dobutamine stimulation exaggerated the observed intracoronary haemodynamics and induced myocardial ischaemia. The intracoronary diagnostic procedures performed were helpful in clarifying the pathophysiological mechanisms of functional coronary obstruction and ischaemia in this malformation. Bypass surgery was successfully performed with symptomatic improvement.

Keywords: coronary anomaly;  Doppler;  intravascular ultrasound;  single coronary ostium;  congenital disorders     

Coronary artery bypass graft surgery in dialysis patients

Objective—To examine the short term results and long term survival of patients on long term dialysis undergoing coronary artery bypass graft surgery.
Methods—A retrospective analysis of 19 patients on established dialysis who underwent coronary revascularisation between 1983 and 1995; 14 patients (73%) had class IV angina and five (25%) had unstable angina requiring heparin and nitrate infusions before surgery.
Results—The 30 day mortality was 5%. Follow up was completed in the remaining 18 patients. The mean follow up time was 34 months (range eight to 61). During the follow up period four patients died of cardiac causes. The actuarial survival at one, two, and three years was 87%, 78%, and 59%, respectively. The overall functional status was significantly improved compared to preoperative levels, with a mean Karnofsky score of 76% (p < 0.01) at three years.
Conclusions—Coronary artery bypass graft surgery can be performed with increased but acceptable morbidity and mortality in chronic dialysis patients. It results in considerable improvement in symptoms and functional status. However, long term survival is limited and this requires further investigation.

     

Exercise capacity in chronic heart failure is related to the aetiology of heart disease

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 (O₂) was higher in the dilated group, while the slope relating carbon dioxide production and ventilation (E/CO₂ 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 O₂ and age (peak O₂ = 33.9 − 0.267*age; r = 0.36; p < 0.001). After correcting for age, the peak achieved O₂ 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.

Keywords: exercise performance;  heart failure;  ischaemic heart disease;  dilated cardiomyopathy