The utility of myocardial perfusion imaging before renal transplantation: a retrospective analysis.

Background: Renal transplantation (RT) reduces morbidity and mortality in patients with end-stage renal failure. Myocardial perfusion imaging provides prognostic information in patients with renal failure, but its role before transplantation remains unclear. We performed a retrospective review assessing the prognostic value of technetium-99m sestamibi myocardial perfusion imaging at a tertiary UK centre.

Renal artery stenosis: an innocent bystander or an independent predictor of worse outcome in patients with chronic heart failure? A magnetic resonance imaging study.

Aims: To investigate the prognostic impact of atherosclerotic renovascular disease in patients with chronic heart failure.

Methods And Results: Patients with heart failure due to left ventricular systolic dysfunction underwent cardiac magnetic resonance imaging and contrast-enhanced magnetic resonance angiography. Renal artery stenosis (RAS) was defined as a luminal narrowing >50%.

Atherosclerotic disease of the abdominal aorta and its branches: prognostic implications in patients with heart failure.

Aortic atherosclerosis reduces compliance in the systemic circulation and increases peripheral resistance, afterload and left ventricular wall stress. In patients with heart failure, these changes can impair left ventricular systolic function and energy efficiency, which could reduce exercise capacity. Though the interaction and the impact of aortic atherosclerosis on left ventricular function have been investigated, its prognostic implications in patients with heart failure are unclear.

Prevalence of scarred and dysfunctional myocardium in patients with heart failure of ischaemic origin: a cardiovascular magnetic resonance study.

Background: Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) can provide unique data on the transmural extent of scar/viability. We assessed the prevalence of dysfunctional myocardium, including partial thickness scar, which could contribute to left ventricular contractile dysfunction in patients with heart failure and ischaemic heart disease who denied angina symptoms.

Methods: We invited patients with ischaemic heart disease and a left ventricular ejection fraction < 50% by echocardiography to have LGE CMR.

Relationship between right ventricular volumes measured by cardiac magnetic resonance imaging and prognosis in patients with chronic heart failure.

Aims: The aim of this study was to investigate the prognostic impact of right ventricular (RV) size in patients with chronic heart failure.

Methods And Results: Normal volunteers (n = 80) and patients (n = 380) with left ventricular (LV) ejection fraction <45% on echocardiography and on optimal treatment for heart failure underwent cardiac magnetic resonance imaging with measurement of LV and RV volumes, mass and ejection fraction. The mean and the standard deviation (SD) of the RV end-systolic volume index in normal subjects were used to define the normal range as: mean RV end-systolic volume index +2 SD.

Comparison of quantitative coronary angiography with intracoronary ultrasound. Can quantitative coronary angiography accurately estimate the severity of a luminal stenosis?

In this study we investigated the accuracy of monoplane and biplane quantitative coronary angiography in estimating the luminal dimensions, using intracoronary ultrasound as gold standard. Biplane angiography and intracoronary ultrasound were performed in 24 arterial segments. The end-diastolic intracoronary ultrasound frames were manually selected and segmented.

ANGIOCARE: an automated system for fast three-dimensional coronary reconstruction by integrating angiographic and intracoronary ultrasound data.

Objectives: The development of an automated, user-friendly system (ANGIOCARE), for rapid three-dimensional (3D) coronary reconstruction, integrating angiographic and, intracoronary ultrasound (ICUS) data.

Methods: Biplane angiographic and ICUS sequence images are imported into the system where a prevalidated method is used for coronary reconstruction. This incorporates extraction of the catheter path from two end-diastolic X-ray images and detection of regions of interest (lumen, outer vessel wall) in the ICUS sequence by an automated border detection algorithm.

The effect of altering heart rate on ventricular function in patients with heart failure treated with beta-blockers.

Background: Beta-blockers are effective for the treatment of heart failure, but their mechanism of action is unresolved. Heart rate reduction may be a central mechanism or a troublesome side effect.

Methods: A randomized, double-blind, parallel group study comparing chronic higher-rate (80 pulses per minute) with lower-rate (60 pulses per minute) pacing in pacemaker-dependent patients with symptomatic left ventricular (LV) systolic dysfunction, receiving beta-blockers.

Flow-mediated changes in pulse wave velocity: a new clinical measure of endothelial function.

Aims: To test whether measuring hyperaemic changes in pulse wave velocity (PWV) could be used as a new method of assessing endothelial function for use in clinical practice.

Methods And Results: Flow-mediated changes in vascular tone may be used to assess endothelial function and may be induced by distal hyperaemia, while endothelium-mediated changes in vascular tone can influence PWV. These three known principles were combined to provide and test a novel method of measuring endothelial function by the acute effects of distal hyperaemia on upper and lower limb PWV (measured by a recently developed method).

The effect of ventricular pacing on measurements of left ventricular function: a comparison between echocardiographic methods and with radionuclide ventriculography.

Aims: Different methods exist for measuring left ventricular function echocardiographically; each may be error prone due to the abnormal pattern of ventricular activation during pacing.

Methods And Results: Echocardiography was undertaken on 307 patients with permanent pacemakers; a subset of 57 underwent radionuclide ventriculography. Intrinsic and paced beats were analysed for left ventricular function by: Simpson's bi-plane, Teicholz M-mode, wall-motion scoring and 'eyeball' assessment.

"Pure" diastolic dysfunction is associated with long-axis systolic dysfunction. Implications for the diagnosis and classification of heart failure.

Aims: To investigate regional systolic function of the left ventricle, to test the hypothesis that "pure" diastolic dysfunction (impaired global diastolic filling, with a preserved ejection fraction > or = 50%) is associated with longitudinal systolic dysfunction.

Methods And Results: One hundred thirty subjects (31 patients with asymptomatic diastolic dysfunction, 30 with diastolic heart failure, 30 with systolic heart failure; and 39 age-matched normal volunteers) were studied by conventional and tissue Doppler echocardiography. Global diastolic function was assessed using the flow propagation velocity, and by estimating left ventricular filling pressure from the ratio of transmitral E and mitral annular E(TDE) velocities (E/E(TDE)); and global systolic function by measurement of ejection fraction.

Myocardial perfusion scintigraphy: the evidence.

This review summarises the evidence for the role of myocardial perfusion scintigraphy (MPS) in patients with known or suspected coronary artery disease. It is the product of a consensus conference organised by the British Cardiac Society, the British Nuclear Cardiology Society and the British Nuclear Medicine Society and is endorsed by the Royal College of Physicians of London and the Royal College of Radiologists. It was used to inform the UK National Institute of Clinical Excellence in their appraisal of MPS in patients with chest pain and myocardial infarction.

Subclinical left ventricular dysfunction in asymptomatic patients with Type II diabetes mellitus, related to serum lipids and glycated haemoglobin.

The aim of the present study was to measure regional ventricular function at rest and during stress in order to assess if patients with Type II diabetes have subclinical myocardial dysfunction and if it is related to risk factors. Seventy subjects (35 patients with Type II diabetes with no symptoms, signs or history of heart disease, and 35 age- and sex-matched healthy controls) had echocardiography at rest and during dobutamine stress. Myocardial velocities were measured off-line from digital loops of colour tissue Doppler.

Arterial distensibility: acute changes following dynamic exercise in normal subjects.

The time course of acute changes in large artery distensibility immediately and for 60 min following maximum treadmill exercise in normal subjects was characterized by simultaneously measuring upper and lower limb pulse wave velocity (PWV). A new oscillometric technique was used, which has proven to be sensitive to changes in distensibility induced by acute changes in vascular tone independently of blood pressure. The observed changes in PWV are attributable to changes in vascular tone corresponding to recovery from a systemic net constrictor response and a local net dilator response to exercise with persisting postexercise vasodilatation.

Left ventricular long-axis diastolic function is augmented in the hearts of endurance-trained compared with strength-trained athletes.

In order to determine left ventricular global and regional myocardial functional reserve in endurance-trained and strength-trained athletes, and to identify predictors of exercise capacity, we studied 18 endurance-trained and 11 strength-trained athletes with left ventricular hypertrophy (172+/-27 and 188+/-39 g/m(2) respectively), and compared them with 14 sedentary controls. Global systolic (ejection fraction) and diastolic (transmitral flow) function, and regional longitudinal and transverse myocardial velocities [tissue Doppler echocardiography (TDE)], were measured at rest and immediately after exercise. In endurance-trained compared with strength-trained athletes, resting heart rate was lower (59+/-11 and 76+/-9 beats/min respectively; P<0.

Estimation of global left ventricular function from the velocity of longitudinal shortening.

Aims: To determine if global ventricular function can be assessed from the long-axis contraction of the left ventricle, we compared pulsed-wave Doppler myocardial imaging of mitral annular motion to radionuclide ventriculography.

Methods And Results: We studied 51 patients (56 +/- 10 years, 11 women) with a radionuclide ejection fraction of 52 +/- 13% (15%-70%). Peak systolic velocities of medial and lateral mitral annular motion correlated with ejection fraction (0.

Fractal dimensions of laser doppler flowmetry time series.

Laser Doppler flowmetry (LDF) provides a non-invasive method of assessing cutaneous perfusion. As the microvasculature under the probe is not defined the measured flux cannot be given absolute units, but the technique has nevertheless proved valuable for assessing relative changes in perfusion in response to physiological stress. LDF signals normally show pronounced temporal variability, both as a consequence of the pulsatile nature of blood flow and local changes in dynamic vasomotor activity.

Relatively low red cell folate levels and acute coronary syndromes.

Background: Low folate levels are related to increased risk for coronary artery disease in humans, while experimental work has shown that folate deficiency is thrombogenic. We hypothesized that relatively low folate levels are related to the development of acute coronary syndromes in patients with previously stable coronary artery disease.

Methods: One hundred and forty-one men were studied: 53 consecutive patients with acute coronary syndromes, 41 with stable coronary artery disease and 47 control participants.

Adenosine provokes diastolic dysfunction in microvascular angina.

Adenosine stress echocardiography was performed in nine patients (58 (+/-3) years, eight women) with documented microvascular angina. Global ventricular function was assessed by Tc(99m) blood pool imaging and Doppler, whereas longitudinal ventricular function was assessed by simultaneous tissue Doppler echocardiography of the lateral mitral annulus. Adenosine was infused incrementally to onset of chest pain in all patients.

Differentiation between pathologic and physiologic left ventricular hypertrophy by tissue Doppler assessment of long-axis function in patients with hypertrophic cardiomyopathy or systemic hypertension and in athletes.

To identify new echocardiographic indexes of long-axis function that might differentiate between pathologic and physiologic left ventricular (LV) hypertrophy, we compared 60 subjects with different types of LV hypertrophy (group I: 15 patients with hypertrophic cardiomyopathy, group II: 15 patients with systemic hypertension, and group III: 30 athletes) with 20 normal subjects (group IV). The peak velocities of mitral annular motion at 4 sites were measured from the apex by tissue Doppler echocardiography. There were no differences in mean age and global ejection fraction between groups.

Syndrome X and endothelial dysfunction.

Objective: Syndrome X (angina, normal coronary arteriogram and positive exercise test) remains an enigma with unexplained features and apparent conflicts of evidence. The present study addressed whether (i) the Syndrome is characterised by generalised flow-related endothelial dysfunction, (ii) myocardial thallium201 defects reflect myocardial or microvascular dysfunction, (iii) endothelial dysfunction and its consequences can be improved by oral L-arginine.

Methods: Flow-mediated brachial artery dilatation was measured by ultrasonic 'wall-tracking' in 7 Syndrome X patients, further characterised as having thallium201 defects and no known cause of endothelial dysfunction, and a normal control group.

Nuclear cardiology in the UK 1994: activity relative to Europe, USA, and British Cardiac Society targets.

Objective: To survey practice in nuclear cardiology in the UK in 1994.

Design: A questionnaire was sent to 219 centres performing nuclear imaging asking for details of current practice in nuclear cardiology. Replies were received from 192 centres (88%).

Nuclear cardiology in the UK: British Nuclear Cardiology Society survey 1994.

This study surveyed practice in nuclear cardiology in the UK in 1994. A questionnaire was sent to 219 centres performing nuclear imaging asking for details of current practice in nuclear cardiology. Replies were received from 192 centres (88%).