Hyperspectral near-infrared spectroscopy assessment of the brain during hypoperfusion

Two-thirds of out-of-hospital cardiac arrest patients, who survive to hospital admission, die in the hospital from neurological injuries related to cerebral hypoperfusion. Therefore, noninvasive real-time monitoring of the cerebral oxygen metabolism in cardiac arrest patients is extremely important. Hyperspectral near-infrared spectroscopy (hNIRS) is a noninvasive technique that measures concentrations of the key chromophores in the brain, such as oxygenated hemoglobin, deoxygenated hemoglobin, and cytochrome C oxidase (CCO), an intracellular marker of oxygen consumption. We tested hNIRS on 10 patients undergoing transcatheter aortic valve insertion, where rapid ventricular pacing (RVP) is required to temporarily induce sudden hypotension and hypoperfusion that mimic cardiac arrest. Using multidistance hNIRS, we found that tissue oxygen saturation changes in the cerebral tissue were lower than those in the scalp during RVP. CCO redox changes were detected in cerebral tissue but not in the scalp during RVP. We have demonstrated that hNIRS is feasible and can detect sudden changes in cerebral oxygenation and metabolism in patients during profound hypotension.

Aortic valve replacement in patients with amyloidosis

BACKGROUND

Outcome data on aortic valve replacement in patients with amyloidosis are limited. To address this issue, we reviewed our experience of patients with amyloidosis who underwent aortic valve replacement.

METHODS

We retrospectively reviewed the records of 16 patients with amyloidosis who underwent aortic valve replacement between May 2000 and February 2017.

RESULTS

The cohort comprised 11 males (69%) and 5 females (31%). The median patient age was 76 years (interquartile range [IQR], 71-82 years), and Society of Thoracic Surgeons predicted rate of mortality was 5.0% (IQR, 2.4%-8.7%). Amyloidosis type was immunoglobulin light chain in 6 patients (38%), age-related in 6 (38%), and localized in 4 (25%). The operation was surgical aortic valve replacement in 11 patients (69%) and balloon-expandable transfemoral transcatheter aortic valve insertion in the other 5. There was no procedure-related stroke, need for new-onset dialysis or pacemaker, or death within 30 days of surgery. The median length of hospital stay was 1 day (IQR, 1-2 days) in the transcatheter valve insertion group and 6 days (IQR, 6-8 days) in the surgical group (P = .002). Follow-up was available for all patients at a median of 1.9 years (IQR, 1.2-4.8 years). During the follow-up period, there were 4 deaths, all occurring >1 year after surgery.

CONCLUSIONS

Aortic valve replacement can be performed with low risk of operative morbidity and mortality in patients with amyloidosis. Transcatheter valve insertion has the advantage of reduced hospital length of stay. The 1-year survival is excellent.

Assisted care as a baseline patient risk characteristic affecting the outcome of transcatheter aortic valve insertion

BACKGROUND

Objective measures of frailty have not been well defined as risk factors for a poor outcome after transcatheter aortic valve insertion. We hypothesized that assisted care as a baseline patient characteristic was a simple objective measure of frailty. We reviewed our experience to assess for an association between assisted care and outcome of operation.

METHODS

We retrospectively reviewed the records of 597 patients operated with transcatheter aortic valve insertion from November 2008 through July 2015. The study cohort included patients with a dichotomous baseline characteristic of receiving assisted care (AC group, n = 60, 10.1%) or not receiving assisted care (NC group, n = 537, 89.9%). The endpoints of the study were operative stroke/death and 1-year survival.

RESULTS

The age of the patients was 80.6 ± 9.0 years, male sex was present in 349 (58.5%), and STS predicted risk of mortality was 9.2 ± 6.2%. Alternate access was used in 26 (43.3%) patients in the AC care group and in 220 (41.0%) in the NC group (P = 0.724). Operative stroke/death occurred in 4 (6.7%) patients in the AC group and in 25 (4.7%) in the NC group (P = 0.492). Mortality at 1 year in the AC group was 14.8 ± 5.2% and in the NC group was 12.9 ± 1.7%; (P = 0. 250).

CONCLUSIONS

Assisted care as a baseline patient characteristic does not result in increased operative stroke/death or 1-year mortality in patients following transcatheter aortic valve insertion. Assisted care should not by itself preclude operation. © 2016 Wiley Periodicals, Inc.