Florian Lüders

Peripheral arterial disease and critical limb ischaemia: still poor outcomes and lack of guideline adherence

AIMS Only few and historic studies reported a bad prognosis of peripheral arterial disease (PAD) and critical limb ischaemia (CLI). The contemporary state of treatment and outcomes should be assessed. METHODS AND RESULTS From the largest public health insurance in Germany, all in- and outpatient diagnosis and procedural data were retrospectively obtained from a cohort of 41 882 patients hospitalized due to PAD during 2009-2011, including a follow-up until 2013. Patients were classified in Rutherford categories 1-3 (n = 21 197), 4 (n = 5353), 5 (n = 6916), and 6 (n = 8416). The proportions of patients with classical risk factors such as hypertension, dyslipidaemia, and smoking declined with higher Rutherford categories (each P < 0.001) while diabetes, chronic kidney disease, and chronic heart failure increased (each P < 0.001). Angiographies and revascularizations were performed less often in advanced PAD (each P < 0.001). In-hospital amputations increased continuously from 0.5% in Rutherford 1-3 to 42% in Rutherford 6, as also myocardial infarctions, strokes, and deaths (each P < 0.001). Among 4298 amputated patients with CLI, 37% had not received any angiography or revascularization neither during index hospitalization nor the 24 months before. During follow-up (mean 1144 days), 7825 patients were amputated and 10 880 died. Kaplan-Meier models projected 4-year mortality risks of 18.9, 37.7, 52.2, and 63.5% in Rutherford 1-3, 4, 5, and 6, and for amputation of 4.6, 12.1, 35.3, and 67.3%, respectively. In multivariable Cox regression models, PAD categories were significant predictors of death, amputation, myocardial infarction, and stroke (each P < 0.001). Length of in-hospital stay (5.8 ± 6.7 days, 10.7 ± 11.1days, 15.2 ± 13.8 days and 22.1 ± 20.3 days; P < 0.001) and mean case costs (3662 ± 3186 €, 5316 ± 6139 €, 6021 ± 4892 €, and 8461 ± 8515 €; P < 0.001) increased continuously in Rutherford 1-3, 4, 5, and 6. While only 49% of the patients suffered from CLI, these produced 65% of in-hospital costs (141 million €), and 56% during follow-up (336 million €). CONCLUSION Regardless of recent advances in PAD treatment, current outcomes remain poor especially in CLI. Despite overwhelming evidence for reduction of limb loss by revascularization, CLI patients still received significantly less angiographies and revascularizations.

Recent trends in morbidity and in-hospital outcomes of in-patients with peripheral arterial disease: a nationwide population-based analysis

AIMS The prevalence of peripheral arterial disease (PAD) and especially of critical limb ischaemia (CLI) is announced to rise dramatically worldwide, with a considerable impact on the health care and socio-economic systems. We aimed to characterize the recent trends in morbidity and in-hospital outcome of PAD among all hospitalized patients in the entire German population between 2005 and 2009. METHODS AND RESULTS Nationwide data of all hospitalizations in Germany in 2005, 2007, and 2009 were analysed regarding the prevalence of PAD, comorbidities, endovascular (EVR) and surgical revascularizations (SR), major and minor amputations, in-hospital mortality, and associated costs. From 2005 to 2009, total PAD cases increased by 20.7% (from 400 928 to 483 961), with an increase of CLI subset from 40.6 to 43.5%. Total EVR increased by 46%, while thromb-embolectomy, endarterectomy, and patch plastic increased by 67, 42, and 21%, respectively. Peripheral bypasses decreased by 2%. Major amputation decreased from 4.6 to 3.5%, while minor amputation slightly increased from 4.98 to 5.11%. The crude overall in-hospital mortality remained unchanged in claudicants (2.2%), while it decreased from 9.8 to 8.4% in CLI patients. However, mortality rate according to the Poisson model (n/1000 hospital residence days) increased significantly in claudicants (P < 0.001). Total reimbursement costs for PAD in-patient care increased by 21% with an average per case costs in 2009 of €4506 in a claudicant and €6791 in a CLI patient. CONCLUSION This population-based analysis documents the significant rise of PAD, particularly of the CLI subset, and highlights the malign prognosis associated with PAD as indicated by high amputation and in-hospital mortality rates.

Amputations and mortality in in-hospital treated patients with peripheral artery disease and diabetic foot syndrome

AIMS The prevalence of diabetes mellitus (DM) and its associated complications such as peripheral artery disease (PAD) and diabetic foot syndrome (DFS) are increasing worldwide. We aimed to determine the contemporary acute and long-term outcome of patients with PAD and DFS in Germany. METHODS Nationwide, anonymized data of 40,335 patients hospitalized for PAD and/or DFS from the years 2009-2011 were analyzed and followed up until 2013. Patients were classified into 3 groups: DFS, PAD+DM and PAD without DM. In-hospital and long-term outcome (1156days, 95% CI 1.151-1.161) regarding major and minor amputation and mortality was assessed. Cumulative amputation-free survival and overall survival rates were calculated using Kaplan-Meier analysis. RESULTS The proportion of DFS, PAD+DM and PAD only was 17.3%, 21.5% and 61.2%, respectively. At index-hospitalization, DFS patients had the highest amputation (31.9% vs. 11.1% vs. 6.0%), yet the lowest revascularization rate (18.2% vs. 67.8% vs. 71.6%) compared to patients with PAD only and PAD+DM (P<0.001). Cumulative 4-year survival (57.4%, 60.8% and 70.0%) and amputation-free-survival (45.4%, 74.4% and 86.5%) were lowest for DFS followed by PAD+DM and PAD only (P<0.001). CONCLUSIONS Patients with diabetes, particularly those with DFS, have persistent high rates of limb amputation and of mortality in a real-world setting. Our data emphasize the need for further dedicated research to identify and target the underlying causes of the extraordinary poor outcome in this high risk population.

Low Rates of Revascularization and High In-Hospital Mortality in Patients With Ischemic Lower Limb Amputation: Morbidity and Mortality of Ischemic Amputation.

Background: To assess the nationwide contemporary burden of cardiovascular risk factors, comorbidities, and in-hospital mortality in patients with lower limb amputation (LLA) due to peripheral arterial disease and critical limb ischemia (CLI) in Germany. Methods: German nationwide data for 2005 and 2009 were analyzed regarding in-hospital rates of major and minor ischemic LLA, risk factors, comorbidities, surgical and endovascular revascularizations, and in-hospital mortality. Results: In 2005, a total of 22 479 major (7.8%) and 28 262 minor (9.8%) LLAs were performed with a relative decrease of −21.8% in major LLA, yet with a relative increase of +2% in minor LLA rate in 2009. The overall revascularization rate before amputation was 46% in 2005 and 57% in 2009. In-hospital mortality for non-CLI, minor, and major amputees was 3.3%, 4.6%, and 19.8%, respectively (P < .001 for major vs minor LLA and non-CLI). Conclusion: The total number of ischemic LLA and amputation-related in-hospital mortality remains high in Germany in the 21st century. The poor outcome of patients with CLI might in part be due to underuse of revascularizations prior to amputation.

CKD and Acute and Long-Term Outcome of Patients with Peripheral Artery Disease and Critical Limb Ischemia

BACKGROUND AND OBJECTIVES Despite the many studies showing an association between CKD and a high risk of ischemic events and mortality, the association of CKD with peripheral arterial disease (PAD) still has not been well described. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This large cohort study assessed the association of CKD, even in the earlier stages, with morbidity, short- and long-term outcome, and costs among patients with PAD. RESULTS We identified 41,882 patients with PAD who had an index hospitalization between January 1, 2009, and December 31, 2011. Of these, 8470 (20.2%) also had CKD (CKD stage 2: n=2158 [26%]; stage 3: n=3941 [47%]; stage 4: n=935 [11%]; stage 5: n=1436 [17%]). The ratio of women to men was 1:1.2. Compared with patients without known CKD, those with CKD had higher frequencies of coronary artery disease (1.8-fold higher; P<0.001), chronic heart failure (3.3-fold higher; P<0.001), and Rutherford PAD categories 5 and 6 (1.8-fold higher; P<0.001); underwent significantly fewer revascularizations (0.9-fold fewer; P<0.001); had a nearly two-fold higher amputation rate (P<0.001); had higher frequencies of in-hospital infections (2.1-fold higher; P<0.001), acute renal failure (2.8-fold higher; P<0.001), and sepsis (1.9-fold higher; P<0.001); had a 2.5-fold higher frequency of myocardial infarction (P<0.001); and had a nearly three-fold higher in-hospital mortality rate (P<0.001). In an adjusted multivariable Cox regression model, CKD remained a significant predictor of long-term outcome of patients with PAD during follow-up for up to 4 years (until December 31, 2012; median, 775 days; 25th-75th percentiles, 469-1120 days); the hazard ratio was 2.59 (95% confidence interval, 2.21 to 2.78; P<0.001). The projected mortality rates after 4 years were 27% in patients without known CKD and 46%, 52%, 72%, and 78% in those with CKD stages 2, 3, 4, and 5, respectively. Lengths of hospital stay and reimbursement costs were on average nearly 1.4-fold higher (P<0.001) in patients who also had CKD. CONCLUSIONS This analysis illustrates the significant and important association of CKD with in-hospital and long-term mortality, morbidity, amputation rates, duration and costs of hospitalization, in-hospital treatment, and complications in patients with PAD.

Impact of Peripheral Arterial Occlusive Disease on the Development of Contrast Medium-Induced Acute Kidney Injury

Background/Aims: Contrast medium-induced acute kidney injury (CI-AKI) is an important complication following the use of iodinated contrast media. It accounts for a significant number of hospital-acquired acute kidney injuries and is associated with increased in-hospital and long-term mortality and immense health care costs. We evaluated whether the presence of peripheral arterial occlusive disease (PAD) affects the incidence of CI-AKI following heart catheterization. Methods: The impact of PAD on the frequency of CI-AKI after heart catheterization was analysed in the prospective single-centre Dialysis-versus-Diuresis trial (January 2001 to July 2004). The patients were retrospectively divided into 3 subgroups: patients with coronary heart disease (CHD), patients with PAD and patients without PAD or CHD. Results: 412 patients were included (83.5% men, 29.1% diabetes mellitus, 4.9% ejection fraction <35%). Of these, 251 (60.9%) suffered from CHD but not from PAD, 77 (18.7%) from PAD and 84 (20.4%) had neither CHD nor PAD. After heart catheterization, 49 (11.9 %) patients developed CI-AKI. Patients with PAD suffered significantly more often from CI-AKI than those without PAD (32.7 vs. 16.8%, p = 0.008). Multivariate analyses by logistic regression confirmed PAD to be an independent predictor of a CI-AKI (odds ratio 2.013, 95% confidence interval 1.009-4.016, p = 0.047). The CHD was not significantly associated with CI-AKI. Conclusion: Patients with PAD significantly more often develop a CI-AKI after heart catheterization than those without PAD.

Association of CKD with Outcomes Among Patients Undergoing Transcatheter Aortic Valve Implantation

BACKGROUND AND OBJECTIVES Despitethe multiple depicted associations of CKD with reduced cardiovascular and overall prognoses, the association of CKD with outcome of patients undergoing transcatheter aortic valve implantation has still not been well described. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Data from all hospitalized patients who underwent transcatheter aortic valve implantation procedures between January 1, 2010 and December 31, 2013 in Germany were evaluated regarding influence of CKD, even in the earlier stages, on morbidity, in-hospital outcomes, and costs. RESULTS A total of 28,716 patients were treated with transcatheter aortic valve implantation. A total of 11,189 (39.0%) suffered from CKD. Patients with CKD were predominantly women; had higher rates of comorbidities, such as coronary artery disease, heart failure at New York Heart Association 3/4, peripheral artery disease, and diabetes; and had a 1.3-fold higher estimated logistic European System for Cardiac Operative Risk Evaluation value. In-hospital mortality was independently associated with CKD stage ≥3 (up to odds ratio, 1.71; 95% confidence interval, 1.35 to 2.17; P<0.05), bleeding was independently associated with CKD stage ≥4 (up to odds ratio, 1.82; 95% confidence interval, 1.47 to 2.24; P<0.001), and AKI was independently associated with CKD stages 3 (odds ratio, 1.83; 95% confidence interval, 1.62 to 2.06) and 4 (odds ratio, 2.33; 95% confidence interval, 1.92 to 2.83 both P<0.001). The stroke risk, in contrast, was lower for patients with CKD stages 4 (odds ratio, 0.23; 95% confidence interval, 0.16 to 0.33) and 5 (odds ratio, 0.24; 95% confidence interval, 0.15 to 0.39; both P<0.001). Lengths of hospital stay were, on average, 1.2-fold longer, whereas reimbursements were, on average, only 1.03-fold higher in patients who suffered from CKD. CONCLUSIONS This analysis illustrates for the first time on a nationwide basis the association of CKD with adverse outcomes in patients who underwent transcatheter aortic valve implantation. Thus, classification of CKD stages before transcatheter aortic valve implantation is important for appropriate risk stratification.

Long-Term Mortality After Invasive Angiography and Endovascular Revascularization in Patients With PAD Having Chronic Kidney Disease

Peripheral arterial disease (PAD) and chronic kidney disease (CKD) are associated with increased mortality rates. We assessed long-term outcomes of patients with PAD and CKD. Patients with PAD undergoing invasive angiography and/or endovascular revascularization between 2005 and 2010 were retrospectively classified into 5 CKD stages. A follow-up was performed and 572 patients were included, 116 patients (20%) had normal renal function, 245 were in CKD stage 2 (43%), 156 in CKD stage 3 (27%), and 55 in CKD stages 4 + 5 (10%). Diabetes mellitus, hypertension, and anemia were more frequent in higher CKD stages (P < .03). During follow-up (mean 1135 days; 95% confidence interval 1159-1259), cumulative mortality was 21% and increased with advanced CKD stages (9%, 16%, 29%, and 47%, respectively, P < .001). In multivariate Cox regression models, higher CKD stages were significantly associated with poor survival. Medication adherence for secondary prevention was significantly lower than recommended but irrespective of CKD stages. Kidney function is an independent predictor of worse long-term survival in patients with PAD. While standard medications were used less often than recommended, no differences between CKD stages were noted.

Prevalence and impact of critical limb ischaemia on in-hospital outcome in transcatheter aortic valve implantation in Germany

AIMS Peripheral artery disease (PAD) is common in patients with aortic valve stenosis (AS). This study sought to assess the prevalence of critical limb ischaemia (CLI) and its impact on in-hospital outcome in patients undergoing transcatheter aortic valve implantation (TAVI) for severe AS. METHODS AND RESULTS All isolated TAVI procedures for AS in Germany between 2007 and 2013 were analysed regarding the stage-specific prevalence of PAD, comorbidities, in-hospital complications and mortality using diagnostic and procedural codes. Among 32,044 patients with TAVI, 3,375 (10.5%) had PAD and 654 (2.0%) CLI. TAVI patients with PAD, particularly those with CLI, had a higher incidence of periprocedural stroke, bleeding and acute kidney injury (p<0.001). The overall in-hospital mortality among TAVI without PAD, non-CLI PAD and CLI was 6.1%, 8.4% and 14.7%, respectively (p<0.001). In a multivariate logistic regression analysis, CLI was an independent predictor of in-hospital mortality (odds ratio 1.96, 95% confidence interval 1.56-2.47; p<0.001). CONCLUSIONS In patients undergoing TAVI, the presence of PAD is associated with an increased risk of periprocedural complications, while only CLI independently predicts increased in-hospital mortality. Whether CLI represents a marker of general poor health status resulting in poor outcome or is a modifiable risk factor whose treatment prior to TAVI can improve the outcome requires prospective studies.

The Impact of Chronic Kidney Disease on Hospitalized Patients With Peripheral Arterial Disease and Critical Limb Ischemia

Peripheral arterial disease (PAD) and chronic kidney disease (CKD) are major public health problems worldwide. Evaluations of large-scale data on morbidity, outcome, and costs in patients having PAD with CKD are essential. Cross-sectional nationwide population-based analysis of all hospitalizations for PAD during 2009 in Germany focused on the stage-related impact of CKD on morbidity, in-hospital mortality, amputations, length of hospital stay, and health-related expenditure. The total number of hospitalizations was 483 961. Of those, 132 993 (27.5%) had CKD. Chronic kidney disease caused 1.8-fold higher amputation rate (P < .001) with a stepwise increasing rate with higher CKD stage. Chronic kidney disease doubled in-hospital mortality of patients with PAD (7.8%; n = 10 421) versus 4.0% (n = 14 174, P < .001) with a stepwise increasing risk with higher CKD stage (P < .001). The highest in-hospital mortality occurred in patients with coprevalence of CKD stage 4 and Fontaine stage IV (16.4%, n = 1176, P < .001). Chronic kidney disease caused 15% higher costs and 21% increased length of stay compared to the whole PAD cohort. This analysis demonstrates the stage-related influence of CKD on morbidity, in-hospital mortality, amputations, length of hospital stay, and reimbursement costs of hospitalized patients with PAD.