Julian Wright

Left Ventricular Morphology and Function in Patients with Atherosclerotic Renovascular Disease

Atherosclerotic renovascular disease (ARVD) is associated with heart disease. There has been no systematic study of cardiac structure and function in patients with this condition. In this study, the epidemiology of cardiac changes and their relationship to renal function, renovascular anatomy, and BP are delineated. With the use of a cross-sectional design, 79 patients with ARVD and 50 control patients without ARVD underwent echocardiography and 24-h ambulatory BP monitoring. Clinical and biochemical data were collected. Results were analyzed according to renal function, residual renal artery patency, and unilateral or bilateral ARVD. Only 4 (5.1%) patients with ARVD had normal cardiac structure and function. Patients with ARVD (age 70.7 +/- 7.5 yr; estimated GFR 36 +/- 19 ml/min) had significantly more cardiovascular comorbidity (77.2 versus 42.0%; P < 0.001), greater prevalence of left ventricular (LV) hypertrophy (78.5 versus 46.0%; P < 0.001) and LV diastolic dysfunction (74.6 versus 40.0%; P < 0.001), and greater LV mass index (183 +/- 74 versus 116 +/- 33 g/m2; P < 0.001) and LV end-diastolic volume index (82 +/- 35 versus 34 +/- 16 ml/m2; P < 0.001) than control subjects. BP was similar for both patient groups. For patients with ARVD, neither renal function nor renal artery patency predicted a difference in echocardiographic or ambulatory BP monitoring parameters. Patients with bilateral ARVD had greater LV mass index and LV dilation than patients with unilateral disease. Patients with ARVD exhibit a high prevalence of cardiac morphologic and functional abnormalities at early stages of renal dysfunction. Such patients must be identified early in their disease course to allow risk factor modification.

Cardiovascular disease in patients with chronic kidney disease

Patients with chronic kidney disease have a high burden of cardiovascular morbidity and mortality. The vast majority of patients with chronic kidney disease do not progress to end stage renal failure, but do have a significantly higher incidence of all cardiovascular co-morbidities. Traditional cardiovascular risk factors only partially account for this increased incidence of cardiovascular disease. In patients with kidney disease the basic biology underlying cardiovascular disease may be similar to that in patients without kidney disease, but it would seem many more risk factors are involved as a consequence of renal dysfunction. Although emphasis is placed on delaying the progression of chronic kidney disease, it must be appreciated that for many patients it is vital to address their cardiovascular risk factors at an early stage to prevent premature cardiovascular death. This review examines available epidemiological evidence, discusses common cardiovascular risk factors in patients with chronic kidney disease, and suggests possible treatment strategies. Potential areas for important research are also described.

Progression of cardiac dysfunction in patients with atherosclerotic renovascular disease

BACKGROUND Patients with atherosclerotic renovascular disease (ARVD) are at increased risk of heart disease because of the association with hypertension, coronary artery disease, cardiac failure and chronic kidney disease (CKD). A previous echocardiographic cross-sectional study showed that only 5% of patients with ARVD had normal cardiac structure and function at baseline. In this longitudinal study of the same patient cohort the progression of cardiac dysfunction and factors which predict declining cardiac function in patients with ARVD were delineated. METHODS Seventy-nine patients were available for baseline analysis, but 16 withdrew from follow-up during the study. Forty-three patients (27M and 16F, age at study entry [mean +/- SD] 69.7 +/- 8.0 years) who were managed conservatively and 8 (age 69.8 +/- 5.7) who were managed with renal revascularization underwent echocardiography and 24 h ambulatory blood pressure investigations at baseline and 12 months thereafter. The two data sets were interrogated to determine changes in blood pressure and cardiac status (morphological and functional); baseline factors which predicted such changes were ascertained. Twelve patients underwent baseline investigation but did not complete follow-up because of death (nine patients) or requirement of dialysis (three patients). RESULTS Conservatively managed patients: At 12 months eGFR, (38.6 +/- 18.3 vs 35.0 +/- 18.5 ml/min; P = 0.001) had fallen whilst proteinuria had increased (0.3 +/- 0.4 vs 0.6 +/- 0.8 g/24 h; P = 0.001). Despite no increase in the number of blood pressure medications there was a fall in blood pressure between baseline and follow-up investigations (140.0 +/- 16.5/75.3 +/- 11.8, MAP 98.6 +/- 12.3 mmHg vs 135.7 +/- 16.1/69.6 +/- 9.1, MAP 92.5 +/- 10.2 mmHg; P < 0.001 for diastolic blood pressure and MAP). At 12 months, there was an increase in the number of patients with LVH (72.9% vs 81.4%). There were increases in left ventricular dimensions [left ventricular end diastolic diameter (5.1 +/- 0.8 vs 5.5 +/- 0.8 cm; P = 0.009), and left ventricular end diastolic volume (140.9 +/- 39.5 vs 163.3 +/- 61.0 ml; P = 0.01)]. There was no significant relationship of these changes in cardiac parameters to anatomical severity of renal artery disease but patients with severe renal dysfunction at baseline had an increase in left ventricular dilatation at follow-up. Linear regression analysis revealed an association between elevated time-averaged PTH and LV dilatation [beta-coefficient and 95% confidence intervals, 0.18 (0.04, 0.32); P = 0.01]. Revascularization: No significant changes in any biochemical or echocardiographic parameters were seen between baseline and 1 year investigations in this small sub-group. CONCLUSION Patients with ARVD exhibit a high prevalence of LVH at diagnosis and progressive left ventricular dilatation over the first year after diagnosis. This dilatation is associated with severe renal impairment at baseline and not associated with anatomical severity of renal artery disease.

The importance of associated extra-renal vascular disease on the outcome of patients with atherosclerotic renovascular disease

Atherosclerotic renovascular disease (ARVD) is a disease of ageing. It is usually a manifestation of widespread vascular disease and although it may be symptomless, many patients with ARVD present with the effects of extra-renal vascular disease, such as peripheral vascular (PVD), coronary heart (CHD) and cerebrovascular disease. ARVD is a common cause of hypertension and chronic renal failure (CRF), and it is one of the most common renal diagnoses in elderly patients accepted on to dialysis programmes with end-stage renal failure (ESRF). The cause of renal impairment in these patients is still a matter of debate. Patients with ARVD have a high mortality, especially those with renal failure. In this review we examine the relationships between ARVD and co-morbid extra-renal vascular disease, and the impact of these associated vascular pathologies upon renal functional and mortality outcomes is considered. The latest evidence concerning the likely pathogenesis of renal dysfunction in patients with ARVD is also reviewed.

Review: The problem of diabetic nephropathy and practical prevention of its progression

In common with all countries in the developed world, the United Kingdom is experiencing a dramatic increase in the incidence of diabetes and chronic kidney disease. The most common cause of renal impairment is diabetes. The evolution of diabetic nephropathy is usually predictable with evidence-based interventions available at each stage. This review examines this evidence and gives practical advice on the management of patients with diabetic nephropathy. Br J Diabetes Vasc Dis , 2008; 8: 272‐277

Role of renal function and cardiac biomarkers (NT-proBNP and Troponin) in determining mortality and cardiac outcome in atheromatous renovascular disease

Background and Aims: Patients with atheromatous renovascular disease (ARVD) have high cardiovascular morbidity and mortality. The cardiac markers N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin (cTnT) are easily measured, yet not widely used in renal patients as they are thought to be inaccurate in renal disease. We aimed to see if these markers could be used as prognostic indicators of cardiovascular events (CVEs) and death in ARVD. Methods: Subjects with ARVD treated in 1 renal center in 2003 were prospectively followed up. NT-proBNP and cTnT at baseline were correlated with CVEs and death, echocardiographic findings and degree of renal artery stenosis. Cutoff levels of 0.03 ng/ml (cTnT) and 43 pmol/l (NT-proBNP) were used. Results: Eighty-two patients (mean ± SD age 69 ± 8 years, mean follow-up 40.2 ± 16.6 months) were suitable for analysis. Twenty-nine percent of patients suffered new CVEs, and 37.8% died. Renal function was a significant predictor of CVEs and death. Patients with a raised NT-proBNP were more likely to die than those in the same chronic kidney disease (CKD) category with normal levels (p < 0.0001) even after adjusting for multivariate factors (hazard ratio 8.3 for high proBNP vs. 3.6 for low proBNP in CKD stage 4–5). Conclusion: No study to our knowledge has looked at both NT-proBNP and cTnT as outcome markers in ARVD. Our study shows that renal function is more important as a marker of suffering a CVE. However, raised NT-proBNP is associated with a greater likelihood of death when subdivided by CKD stage. Early risk stratification by simple measurement of these biomarkers may aid in intensifying management in high-risk patients, although further studies to assess the value of this approach are warranted.

Mentoring as a retention strategy to sustain the rural and remote health workforce

OBJECTIVE To propose a model of mentoring suitable for rural and remote health professionals. DESIGN Given the rural and remote health workforce shortage, mentoring is proposed as a workforce retention strategy. Mentoring literature was reviewed; aspects of mentoring highlighted in the literature were considered to ascertain their suitability for rural and remote health professionals. METHOD A total of 39 mentoring papers were reviewed to outline key factors in mentoring rural and remote health professionals. Using this literature, key ways that rural and remote practice enhance or are barriers to mentoring were identified. From this, a model for mentoring rural and remote health practitioners, students and academics was developed. RESULTS Four models of mentoring were identified: the cloning, nurturing, friendship and apprenticeship models. The apprenticeship model was identified as suitable for students, the nurturing model as suited to new health professionals to rural and remote settings and the friendship model for senior practitioners/academics. Factors more likely to enable mentoring in rural and remote settings were identified as feelings of obligation by senior practitioners, strong relationships between staff, blurred work/social boundaries, lack of hierarchy, inter-professional practice and technology. The barriers identified included workloads, access to mentors, fee-for-service system for some practitioners, conflicts which could jeopardise working and business relationships, and feelings of being judged. CONCLUSIONS A model of mentoring for rural and remote health professionals was presented. Given the potential to strengthen and increase the rural and remote health workforce, trialling such a model is worthwhile and evaluation would identify its impact.

Comparing a longitudinal integrated clerkship with traditional hospital-based rotations in a rural setting

Abstract Context: Longitudinal integrated clerkships (LIC) are widely used as an educational method, particularly in rural areas. They are good for facilitating hands-on learning and deep relationships between student, patients, and supervisors. Objectives: This study sought to examine and compare learning experience of third-year rural medical students studying specialties (women’s health, aged care, child and adolescent heath, mental health, general practice) by either a traditional hospital-based rotation or a LIC in a rural general practice setting. Methods: Data was collected from two groups of rural students (LIC; traditional hospital-based) over two academic years, utilizing focus groups to investigate general experiences of living and learning rurally, within the different educational models. Results: Results reaffirmed that there was no perceived academic disadvantage to studying medicine rurally. Studying medicine in a rural area provides increased access to patients, more hands-on experience, and close relationships with patients and colleagues. LIC students reported increased confidence in clinical skills, felt better prepared for internship, however experienced more social isolation than students in hospital-based rotations. Conclusions: Students undergoing a rural LIC feel more confident in their clinical skills and preparedness for practice than other rural students. This study supports the use of LICs as a powerful educational tool.

Integrated and consumer-directed care: a necessary paradigm shift for rural chronic ill health

Chronic ill health has recently emerged as the most important health issue on a global scale. Rural communities are disproportionally affected by chronic ill health. Many health systems are centred on the management of acute conditions and are often poorly equipped to deal with chronic ill health. Cardiovascular disease (CVD) is one of the most prominent chronic ill health conditions and the principal cause of mortality worldwide. In this paper, CVD is used as an example to demonstrate the disparity between rural and urban experience of chronic ill health, access to medical care and clinical outcomes. Advances have been made to address chronic ill health through improving self-management strategies, health literacy and access to medical services. However, given the higher incidence of chronic health conditions and poorer clinical outcomes in rural communities, it is imperative that integrated health care emphasises greater collaboration between services. It is also vital that rural GPs are better supported to work with their patients, and that they use consumer-directed approaches to empower patients to direct and coordinate their own care.

Effect of renal artery revascularization upon cardiac structure and function in atherosclerotic renal artery stenosis: cardiac magnetic resonance sub-study of the ASTRAL trial

Background Cardiac abnormalities are frequent in patients with atherosclerotic renovascular disease (ARVD). The Angioplasty and Stenting for Renal Artery Lesions (ASTRAL) trial studied the effect of percutaneous renal revascularization combined with medical therapy compared with medical therapy alone in 806 patients with ARVD. Methods This was a pre-specified sub-study of ASTRAL (clinical trials registration, current controlled trials number: ISRCTN59586944), designed to consider the effect of percutaneous renal artery angioplasty and stenting on change in cardiac structure and function, measured using cardiac magnetic resonance (CMR) imaging. Fifty-one patients were recruited from six selected ASTRAL centres. Forty-four completed the study (medical therapy n = 21; revascularization n = 23). Full analysis of CMR was possible in 40 patients (18 medical therapy and 22 revascularization). CMR measurements of left and right ventricular end systolic (LV and RVESV) and diastolic volume (LV and RVEDV), ejection fraction (LVEF) and mass (LVM) were made shortly after recruitment and before revascularization in the interventional group, and again after 12 months. Reporting was performed by CMR analysts blinded to randomization arm. Results Groups were well matched for mean age (70 versus 72 years), blood pressure (148/71 versus 143/74 mmHg), degree of renal artery stenosis (75 versus 75%) and comorbid conditions. In both randomized groups, improvements in cardiac structural parameters were seen at 12 months, but there were no significant differences between treatment groups. Median left ventricular changes between baseline and 12 months (medical versus revascularization) were LVEDV -1.9 versus -5.8 mL, P = 0.4; LVESV -2.1 versus 0.3 mL, P = 0.7; LVM -5.4 versus -6.3 g, P = 0.8; and LVEF -1.5 versus -0.8%, P = 0.7. Multivariate regression also found that randomized treatment assignment was not associated with degree of change in any of the CMR measurements. Conclusions In this sub-study of the ASTRAL trial, renal revascularization did not offer additional benefit to cardiac structure or function in unselected patients with ARVD.