A novel approach to perioperative risk assessment for patients with pulmonary hypertension.

RATIONALE: Pulmonary hypertension (PH) is associated with significant perioperative morbidity and mortality. We hypothesised that pulmonary arterial hypertension (PAH) composite risk assessment scores could estimate perioperative risk for PH patients when adjusted for inherent procedural risk. METHODS: We identified patients in the Johns Hopkins PH Center Registry that had noncardiac surgery (including endoscopies) between September 2015 and January 2020. We collected information on preoperative patient-level and procedural variables and used logistic regression to evaluate associations with a composite outcome of death within 30 days or serious postoperative complication. We generated composite patient-level risk assessment scores for each subject and used logistic regression to estimate the association with adverse surgical outcomes. We adjusted multivariable models for inherent procedural risk of major cardiovascular events and used these models to generate a numerical PH perioperative risk (PHPR) score. RESULTS: Among 150 subjects, 19 (12.7%) reached the primary outcome, including 7 deaths (4.7%). Individual patient-level and procedural variables were associated with the primary outcome (all p<0.05). A composite patient-level risk assessment score built on three noninvasive parameters was strongly associated with reduced risk for poor outcomes (OR=0.4, p=0.03). This association was strengthened after adjusting the model for procedural risk. A PHPR score derived from the multivariable model stratified patients into low (0%), intermediate (≤10%), or high (>10%) risk of reaching the primary outcome. CONCLUSION: Composite PAH risk assessment scores can predict perioperative risk for PH patients after accounting for inherent procedural risk. Validation of the PHPR score in a multicentre, prospective cohort is warranted.

Renin-Angiotensin-Aldosterone System Inhibitor Use and Mortality in Pulmonary Hypertension: Insights From the Veterans Affairs Clinical Assessment Reporting and Tracking Database.

BACKGROUND: The renin-angiotensin-aldosterone system (RAAS) contributes to pulmonary hypertension (PH) pathogenesis. Although animal data suggest that RAAS inhibition attenuates PH, it is unknown if RAAS inhibition is beneficial in PH patients. RESEARCH QUESTION: Is RAAS inhibitor use associated with lower mortality in a large cohort of patients with hemodynamically confirmed PH? STUDY DESIGN AND METHODS: We used the Department of Veterans Affairs Clinical Assessment Reporting and Tracking Database to study retrospectively relationships between RAAS inhibitors (angiotensin converting enzyme inhibitors [ACEIs], angiotensin receptor blockers [ARBs], and aldosterone antagonists [AAs]) and mortality in 24,221 patients with hemodynamically confirmed PH. We evaluated relationships in the full and in propensity-matched cohorts. Analyses were adjusted for demographics, socioeconomic status, comorbidities, disease severity, and comedication use in staged models. RESULTS: ACEI and ARB use was associated with improved survival in unadjusted Kaplan-Meier survival analyses in the full cohort and the propensity-matched cohort. This relationship was insensitive to adjustment, independent of pulmonary artery wedge pressure, and also was observed in a cohort restricted to individuals with precapillary PH. AA use was associated with worse survival in unadjusted Kaplan-Meier survival analyses in the full cohort; however, AA use was associated less robustly with mortality in the propensity-matched cohort and was not associated with worse survival after adjustment for disease severity, indicating that AAs in real-world practice are used preferentially in sicker patients and that the unadjusted association with increased mortality may be an artifice of confounding by indication of severity. INTERPRETATION: ACEI and ARB use is associated with lower mortality in veterans with PH. AA use is a marker of disease severity in PH. ACEIs and ARBs may represent a novel treatment strategy for diverse PH phenotypes.

The Association of Ambient Air Pollution with Sleep Apnea: The Multi-Ethnic Study of Atherosclerosis.

RATIONALE: Air pollution may influence sleep through airway inflammation or autonomic nervous system pathway alterations. Epidemiological studies may provide evidence of relationships between chronic air pollution exposure and sleep apnea. OBJECTIVES: To determine whether ambient-derived pollution exposure is associated with obstructive sleep apnea and objective sleep disruption. METHODS: We analyzed data from a sample of participants in MESA (Multi-Ethnic Study of Atherosclerosis) who participated in both the Sleep and Air studies. Mean annual and 5-year exposure levels to nitrogen dioxide (NO2) and particulate matter ≤ 2.5 µm in aerodynamic diameter (PM2.5) were estimated at participants' homes using spatiotemporal models based on cohort-specific monitoring. Participants completed in-home full polysomnography and 7 days of wrist actigraphy. We used multivariate models, adjusted for demographics, comorbidities, socioeconomic factors, and site, to assess whether air pollution was associated with sleep apnea (apnea-hypopnea index ≥ 15) and actigraphy-measured sleep efficiency. RESULTS: The participants (n = 1,974) were an average age of 68 (±9) years, 46% male, 36% white, 24% Hispanic, 28% black, and 12% Asian; 48% had sleep apnea and 25% had a sleep efficiency of ≤88%. A 10 ppb annual increase in NO2 exposure was associated with 39% greater adjusted odds of sleep apnea (95% confidence interval [CI], 1.03-1.87). A 5 µg/m3 greater annual PM2.5 exposure was also associated with 60% greater odds of sleep apnea (95% CI, 0.98-2.62). Sleep efficiency was not associated with air pollution levels in fully adjusted models. CONCLUSIONS: Individuals with higher annual NO2 and PM2.5 exposure levels had a greater odds of sleep apnea. These data suggest that in addition to individual risk factors, environmental factors also contribute to the variation of sleep disorders across groups, possibly contributing to health disparities.

Protocol for exercise hemodynamic assessment: performing an invasive cardiopulmonary exercise test in clinical practice.

Invasive cardiopulmonary exercise testing (iCPET) combines full central hemodynamic assessment with continuous measurements of pulmonary gas exchange and ventilation to help in understanding the pathophysiology underpinning unexplained exertional intolerance. There is increasing evidence to support the use of iCPET as a key methodology for diagnosing heart failure with preserved ejection fraction and exercise-induced pulmonary hypertension as occult causes of exercise limitation, but there is little information available outlining the methodology to use this diagnostic test in clinical practice. To bridge this knowledge gap, the operational protocol for iCPET at our institution is discussed in detail. In turn, a standardized iCPET protocol may provide a common framework to describe the evolving understanding of mechanism(s) that limit exercise capacity and to facilitate research efforts to define novel treatments in these patients.