Viehman, Jason K.

Background Little is known about the prognostic significance of monoclonal gammopathy of undetermined and renal significance (MGUS and MGRS) in patients with CKD. The objective of this study was to determine the clinical and kidney outcomes of patients with CKD with either MGUS or MGRS compared with those with CKD without MGUS or MGRS. Methods We conducted a retrospective cohort study from 2013 to 2018. Patients who had both CKD diagnosis and monoclonal testing were identified. Patients were divided into MGRS, MGUS, and no monoclonal gammopathy groups. Cumulative incidence functions and Cox proportional hazards regression were used to model time to event data and to evaluate the association between monoclonal gammopathy status and risk of kidney failure, with death treated as a competing risk. Results Among 1535 patients, 59 (4%) had MGRS, 648 (42%) had MGUS, and 828 (54%) had no monoclonal gammopathy. Unadjusted analysis showed that compared with no monoclonal gammopathy patients, patients with MGRS were at higher risk of kidney failure (hazard ratio [HR] [95% confidence interval]: 2.5 [1.5 to 4.2] but not patients with MGUS (HR [95% confidence interval]: 1.3 [0.97 to 1.6]), after taking death into account as a competing risk. However, in the multivariable analysis, after adjusting for age, sex, eGFR, proteinuria, and Charlson Comorbidity Index, the risk of progression to kidney failure (with death as competing risk) in the MGRS group was no longer statistically significant (HR: 0.9 [0.5 to 1.8]). The same was also true for the MGUS group compared with the group with no monoclonal gammopathy (HR: 1.3 [0.95 to 1.6]). When evaluating the association between MGUS/MGRS status and overall survival, MGRS was significantly associated with mortality in fully adjusted models compared with the group with no monoclonal gammopathy, while MGUS was not. Conclusions After adjusting for traditional risk factors, MGUS/MGRS status was not associated with a greater risk of kidney failure, but MGRS was associated with a higher risk of mortality compared with patients with no monoclonal gammopathy.

Background The impact of changes in Doppler‐derived kidney venous flow in heart failure (HF) is not well studied. We aimed to investigate the association of Doppler‐derived kidney venous stasis index (KVSI) and intrakidney venous‐flow (IKVF) patterns with adverse cardiorenal outcomes in patients with HF. Methods and Results In this observational cohort study, consecutive inpatients with HF referred to a nephrologist because of a history of diuretic resistance and abnormal kidney function (n=216) underwent spectral kidney assessments after admission (Doppler 1) and 25 to 35 days later (Doppler 2) to identify IKVF patterns (continuous/pulsatile/biphasic/monophasic) and KVSI levels. Cox proportional hazard regression models were used to evaluate the associations between KVSI/IKVF patterns at Doppler 1 as well as changes from Doppler 1 to Doppler 2 and risk of cardiorenal events up to 18 months after admission. Worsening HF or death occurred in 126 patients. Both baseline KVSI (hazard ratio [HR], 1.49 [95% CI, 1.37–1.61] per 0.1‐unit increase) and baseline IKVF pattern (HR, 2.47 [95% CI, 2.01–3.04] per 1 pattern severity increase) were significantly associated with worsening HF/death. Increases in both KVSI and IKVF pattern severity from Doppler 1 to 2 were also associated with an increased risk of worsening HF/death (HR, 3.00 [95% CI, 2.08–4.32] per 0.1‐unit increase change; and HR, 6.73 [95% CI, 3.27–13.86] per 1 pattern increase in severity change, respectively). Similar results were observed for kidney outcomes. Conclusions Baseline kidney venous flow predicted adverse cardiorenal events, and inclusion of serial kidney venous flow in cardiorenal risk stratification could facilitate clinical decision‐making for patients with HF. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03039959.

Abstract OBJECTIVES This study analyzes the safety and outcomes of mitral valve repair for degenerative mitral valve regurgitation in patients 75 years of age or older. METHODS We retrospectively reviewed the clinical results of 343 patients aged ≥75 years who underwent mitral valve repair for degenerative mitral valve regurgitation as a primary indication between January 1998 and June 2017. RESULTS The median (interquartile range) age of the patients was 79.4 (76.9, 82.9) years, and 132 (38.5%) patients were women. Concomitant procedures were performed in 123 patients: tricuspid surgery in 68 (19.8%) and a maze procedure or pulmonary vein isolation in 55 (16.0%). Operative mortality was 1.2%. Operative complications included atrial fibrillation in 37.9%, prolonged ventilation in 7.0%, pacemaker implantation in 3.8, renal failure requiring dialysis in 1.5 and stroke in 3 (0.9%). The median follow-up was 7.4 years (interquartile range, 3.5–14.1 years). The cumulative incidence rates of mitral valve reoperation were 2.2%, 3.2% and 3.2% at 1, 5 and 10 years, respectively. Overall survival at 1, 5 and 10 years were 95%, 83% and 51%, respectively. Older age, smoking and over and underweight were associated with increased risk of mortality, while higher left ventricular ejection fraction and hypertension were associated with reduced risk. CONCLUSIONS Mitral valve repair in elderly patients can be accomplished with low operative mortality and complications. Mitral valve repair in the elderly remains the preferred treatment for degenerative mitral regurgitation.

Background Pericardiectomy for post-radiation constrictive pericarditis has been reported to generally have unfavorable outcomes. This study sought to evaluate surgical outcomes in a large cohort of patients undergoing pericardiectomy for radiation-associated pericardial constriction. Methods A retrospective analysis of all patients (≥18years) who underwent pericardiectomy for a diagnosis of constrictive pericarditis with a prior history of mediastinal irradiation from June 2002 to June 2019 was conducted. There were 100 patients (mean age 57.2±10.1 years, 49% females) who met the inclusion criteria. Records were reviewed to look at surgical approach, extent of resection, early mortality and late survival. Results The overall operative mortality was 10.1% (n=10). The rate of operative mortality decreased over the study period; however, the test of trend was not statistically significant (P=0.062). Hodgkin’s disease was the most common malignancy (64%) for which mediastinal radiation had been received. Only 27% patients had an isolated pericardiectomy, and concomitant pericardiectomy and valve surgery was performed in 46% patients. Radical resection was performed in 50% patients, whereas 47% patients underwent a subtotal resection. Prolonged ventilation (26%), atrial fibrillation (21%) and pleural effusion (16%) were the most common post-operative complications. The overall 1,5- and 10-years survival was 73.6%, 53.4% and 32.1% respectively. Increasing age (HR 1.044, 95%CI 1.017-1.073) appeared to have a significant negative effect on overall survival in the univariate model. Conclusion Pericardiectomy performed for radiation associated constrictive pericarditis has poor long-term outcomes. The early mortality, though high (~10%), has been showing a decreasing trend in the test of time.

Abstract Background Primary hyperoxaluria (PH) type 3 (PH3) is caused by mutations in the hydroxy-oxo-glutarate aldolase 1 gene. PH3 patients often present with recurrent urinary stone disease in the first decade of life, but prior reports suggested PH3 may have a milder phenotype in adults. This study characterized clinical manifestations of PH3 across the decades of life in comparison with PH1 and PH2. Methods Clinical information was obtained from the Rare Kidney Stone Consortium PH Registry (PH1, n = 384; PH2, n = 51; PH3, n = 62). Results PH3 patients presented with symptoms at a median of 2.7 years old compared with PH1 (4.9 years) and PH2 (5.7 years) (P = 0.14). Nephrocalcinosis was present at diagnosis in 4 (7%) PH3 patients, while 55 (89%) had stones. Median urine oxalate excretion was lowest in PH3 patients compared with PH1 and PH2 (1.1 versus 1.6 and 1.5 mmol/day/1.73 m2, respectively, P < 0.001) while urine calcium was highest in PH3 (112 versus 51 and 98 mg/day/1.73 m2 in PH1 and PH2, respectively, P < 0.001). Stone events per decade of life were similar across the age span and the three PH types. At 40 years of age, 97% of PH3 patients had not progressed to end-stage kidney disease compared with 36% PH1 and 66% PH2 patients. Conclusions Patients with all forms of PH experience lifelong stone events, often beginning in childhood. Kidney failure is common in PH1 but rare in PH3. Longer-term follow-up of larger cohorts will be important for a more complete understanding of the PH3 phenotype.