Independent prognostic value of high-risk ventricular premature complexes during exercise or recovery in asymptomatic patients: A meta-analysis of observational studies.

INTRODUCTION: Ventricular premature contractions (VPCs) are a common finding during cardiac stress tests. The independent prognostic value of these findings in patients in asymptomatic patients is unclear. METHODS: We conducted a systematic review and meta-analysis of observational studies exploring the independent prognostic value of VPCs to predict all-cause mortality. The secondary outcome was cardiovascular (CV) mortality. We excluded studies that did not report outcomes after adjusting for ≥1 confounder. Random effect meta-analyses were used to predict cumulative hazard ratios. We stratified results based on VPC during exercise or recovery. RESULTS: We found 7 studies with 24,518 patients that met our inclusion criteria. Two studies reported all-cause mortality only, 1 study reported CV mortality only, rest 4 reported both. There was significant heterogeneity in the baseline population, definition of high-risk VPCs, and variables used in adjusted models. Using multivariable summary estimates from individual studies, only VPCs during exercise were associated with a higher risk of all-cause mortality (HR 1.27, 95 % CI 1.07, 1.48). Both VPCs during exercise and recovery were associated with a higher risk CV mortality (HR 1.69, 95 % CI 1.19, 2.20, I2 = 17.6 % and 1.62, 95 % CI 1.25, 2.00, p < 0.001 for both). CONCLUSION: High-risk VPCs during exercise is associated with increased risk of all-cause and CV mortality, while those during recovery are associated with an increased risk of CV mortality only.

Investigation of ventriculoperitoneal shunt disconnection for hydrocephalus treatment.

OBJECTIVE: This investigation is aimed at gaining a better understanding of the factors that lead to mechanical failure of shunts used for the treatment of hydrocephalus, including shunt catheter-valve disconnection and shunt catheter fracture. METHODS: To determine the root cause of mechanical failure, the authors created a benchtop mechanical model to mimic mechanical stressors on a shunt system. To test shunt fracture, cyclical loading on the catheter-valve connection site was tested with the shunt catheter held perpendicular to the valve. Standard methods were used to secure the catheter and valves with Nurolon. These commercial systems were compared to integrated catheters and valves (manufactured as one unit). To test complete separation/disconnection of the shunt catheter and valve, a parallel displacement test was conducted using both Nurolon and silk sutures. Finally, the stiffness of the catheters was assessed. All mechanical investigations were conducted on shunts from two major shunt companies, assigned as either company A or company B. RESULTS: Cyclical loading experiments found that shunts from company B fractured after a mean of 4936 ± 1725 cycles (95% CI 2990-6890 cycles), while those of company A had not failed after 8000 cycles. The study of parallel displacement indicated complete disconnection of company B's shunt catheter-valve combination using Nurolon sutures after being stretched an average 32 ± 5.68 mm (95% CI 25.6-38.4 mm), whereas company A's did not separate using either silk or Nurolon sutures. During the stiffness experiments, the catheters of company B had statistically significantly higher stiffness of 13.23 ± 0.15 N compared to those of company A, with 6.16 ± 0.29 N (p < 0.001). CONCLUSIONS: Mechanical shunt failure from shunt catheter-valve disconnection or fracture is a significant cause of shunt failure. This study demonstrates, for the first time, a correlation between shunt catheters that are less mechanically stiff and those that are less likely to disconnect from the valve when outstretched and are also less likely to tear when held at an angle from the valve outlet. The authors propose an intervention to the standard of care wherein less stiff catheters are trialed to reduce disconnection.

Procedural outcomes of deep brain stimulation (DBS) surgery in rural and urban patient population settings.

Presently, disparities exist between race, sex, socioeconomic status, hospitals, income, comorbidities, and insurance profiles of patients undergoing DBS surgery. Here, we aim to highlight several variables and their predictive powers of DBS surgery outcomes as measured by dischargelocation, length of hospital stays, and total hospital charges. A retrospective cohort study using discharge data from NIS and HCUP for analyses and regression model statistics is performed. Comparative analyses demonstrate urban patients were more often non-routinely discharged, possessed private insurance, and accrued greater hospital costs compared to rural patients. Moreover, regression analyses predicts urban patients have 70% lower odds of routine discharge while those with a major loss of function prior to surgery also have 81% lower odds of routine discharge compared to those with minor loss of function. Ultimately, our study found urban patients or patients with major illnesses have higher hospital charges, longer hospitalization, and more often non-routinely discharged.