Elevated serum urea-to-creatinine ratio is associated with adverse inpatient clinical outcomes in non-end stage chronic kidney disease.

To better understand the role of the urea-to-creatinine ratio in chronic kidney disease patients, we assessed the epidemiology of the urea-to-creatinine ratio among hospitalised chronic kidney disease patients, and the association between the urea-to-creatinine ratio and inpatient clinical outcomes. This retrospective cohort study (n = 11,156) included patients with at least two eGFR values < 60 mL/min/1.73m2 measured greater than 90-days apart and admitted to a tertiary hospital between 2014 and 2019. Dialysis and renal transplant patients were excluded. Adjusted odds ratios for factors associated with an elevated urea-to-creatinine ratio were calculated. Multivariate regression was conducted to identify the relationship between elevated UCR and inpatient mortality, intensive care admission, hospital readmission and hospital length-of-stay. Urea-to-creatinine ratio > 100 was present in 27.67% of hospital admissions. Age ≥ 65 years, female gender, gastrointestinal tract bleeding, heart failure, acute kidney injury and lower serum albumin were associated with elevated urea-to-creatinine ratio. Higher urea-to-creatinine ratio level was associated with greater rates of inpatient mortality, hospital readmission within 30-days and longer hospital length-of-stay. Despite this, there was no statistically significant association between higher urea-to-creatinine ratio and intensive care unit admission. Elevated urea-to-creatinine ratio is associated with poor clinical outcomes in chronic kidney disease inpatients. This warrants further investigation to understand the pathophysiological basis for this relationship and to identify effective interventions.

Evolving mortality rates in people who inject drugs: An Australian tertiary hospital observational study on infective endocarditis.

BACKGROUND: Injection drug use (IDU) associated infective endocarditis (IE) is clinically challenging due to social issues this population endures. Rates of IDU are rising globally, however, there is a lack of clear guidelines for IDU associated IE. The aim of this study is to assess the epidemiology of the IDU and non-IDU populations and compare their long-term outcomes to help guide future management. METHODS: An observational cohort study was conducted on all 350 patients treated for IE at St Vincent's Hospital Melbourne between 1999 and 2015. Follow up was performed until death or January 2021. Primary outcome was all-cause mortality. RESULTS: IDU patients are younger (p<0.001), more likely to have concurrent infections (p<0.001), and other addiction disorders (p<0.001), while non-IDU patients are older with a higher level of comorbid illnesses (p<0.001). IDU and non-IDU patients received similar management during their admissions and experienced similar levels of in-hospital outcomes, except for non-IDU patient being more likely to develop pneumonia post-surgery (p = 0.03). IDU patients are more likely to become reinfected (p = 0.034) but have better long-term survival, with survival estimates at 15-years being 64.98% (95%CI: 50.94-75.92%) for IDU patients compared to 26.67% (95%CI: 19.76-34.05%) for non-IDU patients (p<0.001). CONCLUSION: Despite having higher levels of reinfection, IDU patients have better long-term survival compared to non-IDU patients. Therefore, we suggest IDU patients should not have blanket restrictions on the management they are offered unless at the individual level there is a contraindication to therapy.

Pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension: a systematic review.

Background: Pulmonary thromboendarterectomy (PTE) is the gold standard treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, the results are poorly quantified outside a few registry reports and several individual centers. Methods: A systematic review was performed searching five electronic databases assessing the outcomes for adult patients undergoing PTE for CTEPH. All articles that reported mortality data were included. Primary outcome measures were early/inpatient mortality; secondary outcomes were survival, pulmonary haemodynamics, morbidity and functional status following PTE for CTEPH. Results were pooled via a meta-analysis of proportions and meta-regression. Results: A total of 5,717 studies were identified, yielding sixty-one relevant papers. Thirty-day mortality ranged from 0.8% to 24.4%, and on meta-analysis was 8.4% [95% confidence interval (CI): 7.2-9.6%]. Mortality was noted to decrease with increasing center volume of PTE cases (P<0.01). Residual pulmonary hypertension was reported in 8.2% to 44.5% of patients. Conclusions: CTEPH is associated with acceptable short-term mortality and an improvement in pulmonary hemodynamics. With increasing volume of experience and ongoing developments over time peri-operative mortality continues to decrease.

Multivalve infective endocarditis in intravenous drug using patients: an epidemiological study.

BACKGROUND: Infective endocarditis (IE) remains a life-threatening condition. Intravenous drug use (IVDU) adds to the clinical challenge associated with IE due to clinical aberrations caused by the social issues associated with this population. AIM: To improve survival, this study aimed to characterize the contemporary IVDU-associated IE population seen at our tertiary hospital, determine their long-term outcomes and find risk factors associated with mortality. DESIGN: Retrospective observational cohort study. METHODS: A total of 79 patients accounting for 89 presentations were treated for IVDU-associated IE at St Vincent's Hospital Melbourne (SVHM) between 1999 and 2015. Patients were followed-up until death or January 2021. The primary outcome was all-cause mortality and Kaplan-Meier survival analysis was used to calculate long-term survival estimates. Cox proportional hazards analysis was used to examine risk factors for mortality. RESULTS: The IVDU population treated at SVHM had a high rate of multivalvular IE, at 18.98%. Multivariate analysis revealed that multivalvular IE is significantly associated with an increased risk of mortality in a dose-dependent relationship (two valves affected: HR = 4.73, P = 0.006, three valves affected: HR = 14.19, P = 0.014). The IVDU population has survival estimates of 83.78% (95%CI: 73.21-90.45%) at 1-year and 64.98% (95%CI: 50.94-75.92%) at 15-years. CONCLUSION: IVDU patients have high rates of multivalvular endocarditis, which is associated with increased risk of mortality and difficult to identify on echocardiography. Clinicians should be suspicious of multivalve involvement in the IVDU population and decisions related to medical management/intervention should be made with the understanding that these patients are at a higher risk of death.

Serum potassium abnormalities in chronic kidney disease: prevalence, patient characteristics and clinical outcomes.

BACKGROUND: Abnormalities in serum potassium are a well known complication of chronic kidney disease (CKD), but little is known about their impact on inpatient outcomes. AIMS: To better understand the role of dyskalaemia in hospital in-patients, we assessed the epidemiology of potassium disorders among CKD patients, and the association between admission potassium and inpatient mortality or intensive care unit (ICU) requirement. METHODS: This retrospective hospital-based cohort study (n = 11 156) included patients with an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 admitted to Austin Health between 2014 and 2018 and who had an admission potassium value. Dialysis patients or those with a renal transplant were excluded. Multivariate logistic analysis was conducted to identify factors associated with hyperkalaemia (≥5.5 mmol/L) and hypokalaemia (<3.5 mmol/L). Odds ratios for inpatient mortality and ICU admission between potassium categories were obtained by multivariate regression with adjustments for demographics, renal function and comorbidities. RESULTS: Hyperkalaemia and hypokalaemia were present in 6.86% and 2.94% of hospital admissions respectively. In multivariate regression male sex, lower eGFR, diabetes and cardiac failure were associated with higher odds of hyperkalaemia. Thiazide diuretics, loop diuretics, infectious disease and endocrine pathology were associated with higher odds of hypokalaemia. A U-shaped association was noted between potassium and inpatient mortality. Potassium <4.0 mmol/L and ≥5.0 mmol/L was associated with increased mortality. Only patients with potassium ≥5.5 mmol/L had increased ICU admission risk. CONCLUSION: Derangements in potassium frequently occur in CKD inpatients and are independently associated with higher mortality and ICU requirement. Further studies are required to determine whether interventions to maintain normokalaemia improve outcomes in this population.

Predictors of Pacemaker Insertion Post-Sutureless (Perceval) Aortic Valve Implantation.

INTRODUCTION: The use of rapid deployment sutureless aortic valve replacement (AVR) has become a viable alternative to conventional AVR especially in intermediate and high-risk patients. However, sutureless AVR has been associated with increased rates of permanent pacemaker (PPM) implantation compared with conventionally implanted aortic valve prostheses. The aim of this study was to determine predictive factors for complete heart block requiring insertion of a PPM post-AVR with a Perceval S sutureless valve (LivaNova, London, UK). Such knowledge will help to improve patient counselling, selection and management of patients undergoing sutureless AVR. METHODOLOGY: A retrospective cohort study assessed all patients who underwent insertion of the Perceval sutureless aortic valve prosthesis between July 2015 and September 2019. Medical records were reviewed for demographic, preoperative electrocardiograph (ECG), and operative features related to postoperative PPM implantation and follow-up in the electrophysiology clinic. RESULTS: One hundred and thirty (130) patients without pre-existing PPM underwent sutureless AVR (66.9% male, average age 74.4±6.6 years). Fifty-seven (57) underwent concomitant cardiac surgical procedures. Eight (8) patients underwent redo cardiac surgery. Nineteen (19) of the 130 (14.6%) patients required insertion of a PPM during their postoperative course. Factors associated with PPM insertion were right bundle branch block (overall n=15, PPM vs No PPM: 8/19 vs 7/111 [42.1 % vs. 6.31 %; p<0.01]), longer QRS duration 113.32ms±22.24 ms vs 100.52±20.96 ms (p=0.017) and longer PR Interval 185.166±42.38 ms vs 169.23±25.70 ms (p=0.03). CONCLUSION: Insertion of rapid deployment sutureless aortic valves in the setting of pre-existing right bundle branch block, prolonged QRS complex and longer PR intervals is associated with increased risk of postoperative PPM requirement. These factors should be considered when preoperatively counselling and postoperatively managing patients when balloon expandable sutureless valves are used.