INTRODUCTION:Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder with important cardiovascular implications. Left atrial abnormality can be identified by electrocardiographic P-wave morphology and is considered an important risk for atrial fibrillation (AF) and stroke, both of which have been associated with OSA. We hypothesized that severity of OSA would be associated with more abnormal electrocardiographic P-wave morphology as indicated by P-wave terminal force in V1 (PTFV1 ) and P-wave area in V1 (PWAV1 ).METHODS:Patients who underwent clinically indicated polysomnography and had 12-lead ECG were identified through medical record review. Logistic regression was used to determine the associations between the measures of OSA severity (apnea hypopnea index [AHI] and mean nocturnal oxygen [O2 ] saturation) and abnormal PTFV1 and PWAV1 (defined by >75% percentile value of the studied cohort) adjusting for age, sex, body mass index, and hypertension.RESULTS:A total of 261 patients (mean age: 57 years old, male: 52%) were included in the study. Multivariate analysis showed that AHI was associated with abnormal PTFV1 (>7,280 µV ms) and PWAV1 (>1,000 µV ms; OR: 1.5; 95% CI [1.1, 2.0], p = 0.008; OR: 1.5 [1.1, 2.1], p = 0.005 per 1 SD increase in AHI, respectively). Mean O2 saturation was associated with abnormal PWAV1 (OR: 0.72 [0.54, 0.98], p = 0.03). Results remained unchanged after excluding patients taking AV nodal blocking agents.CONCLUSION:In a sleep clinic cohort, there was significant association between OSA severity and ECG-defined left atrial abnormality.

Background Pulmonary artery (PA) pulsitility index (PAPi) is a novel haemodynamic index shown to predict right ventricular failure in acute inferior myocardial infarction and post left ventricular assist device surgery. We hypothesised that PAPi calculated as [PA systolic pressure - PA diastolic pressure]/right atrial pressure (RAP) would be associated with mortality in the National Institutes of Health Registry for Primary Pulmonary Hypertension (NIH-RPPH). Methods The impact of PAPi, the Pulmonary Hypertension Connection (PHC) risk score, right ventricular stroke work, pulmonary artery capacitance (PAC), other haemodynamic indices, and demographic characteristics was evaluated in 272 NIH-RPPH patients using multivariable Cox proportional hazards (CPH) regression and receiver operating characteristic (ROC) analysis. Results In the 272 patients (median age 37.7 +/- 15.9 years, 63% female), the median PAPi was 5.8 (IQR 3.7-9.2). During 5 years of follow-up, 51.8% of the patients died. Survival was markedly lower (32.8% during the first 3 years) in PAPi quartile 1 compared with the remaining patients (58.5% over 3 years in quartiles 2-4; p < 0.0001). The best multivariable CPH survival model included PAPi, the PHC-Risk score, PAC, and body mass index (BMI). In this model, the adjusted hazard ratio for death with increasing PAPi was 0.946 (95% CI 0.905-0.989). The independent ROC areas for 5-year survival based on bivariable logistic regression for PAPi, BMI, PHC Risk, and PAC were 0.63, 0.62, 0.64, and 0.65, respectively (p < 0.01). The ROC area for 5-year survival for the multivariable logistic model with all four covariates was 0.77 (p < 0.0001). Conclusions Pulmonary artery pulsatility index was independently associated with survival in PAH, highlighting the utility of PAPi in combination with other key measures for risk stratification in this population.

BackgroundPulmonary hypertension (PH) is characterized by increased pulmonary vascular resistance leading to right heart failure. Elevated right atrial (RA) pressure reflects right ventricular (RV) pressure overload and is an established risk factor for mortality in PH. We hypothesized that PH patients with an increased ratio of RA to LA volume index (RAVI/LAVI), would have increased mortality.MethodsWe evaluated the association of RAVI/LAVI with mortality in 124 patients seen at a single academic center's PH clinic after adjusting for the REVEAL risk score, an established risk score in PH. LA and RA volume indices were measured in the four‐and two‐chamber views by two independent researchers. Multivariable logistic regression was used to model the independent association of RAVI/LAVI with survival.ResultsAmong 124 patients (mean age 62 ± 12.7 years, 68.6% female), each unit increase in RAVI/LAVI was associated with a nearly twofold increase in mortality (OR: 1.91, 95% CI: 1.20–3.04). In a multivariable logistic regression, each unit increase in RAVI/LAVI was associated with a nearly twofold increase in mortality (OR: 1.73, 95% CI: 1.003–2.998). Furthermore, RAVI/LAVI in the highest quartile (>1.42) was significantly associated with elevated right atrial pressure (RAP) to pulmonary artery wedge pressure ratio (RAP/PAWP) (0.76 ± 0.41, P = 0.02) compared with the lowest quartile (<0.77), suggesting an interaction between invasive hemodynamic data, atrial structural changes, and mortality in PH.ConclusionsIncreased RAVI/LAVI in PH is associated with decreased survival and accounts for atrial structural remodeling related to invasive hemodynamics. These findings support further study of this index in predicting outcomes in PH.

BackgroundThis study evaluated the utility of a novel index, pulmonary arterial (PA) proportional pulse pressure (PAPP; range 0–1, defined as [PA systolic pressure – PA diastolic pressure] / PA systolic pressure), in predicting mortality in patients with World Health Organization group 1 pulmonary hypertension (PH).HypothesisLow PAPP is associated with increased 5‐year mortality independent of a validated contemporary risk‐prediction equation (Pulmonary Hypertension Connection [PHC] equation).MethodsIn a group of 262 patients in the National Institutes of Health Primary Pulmonary Hypertension (NIH‐PPH) Registry, PAPP and the PHC risk equation were used to predict mortality during 5 years of follow‐up using Cox proportional hazards models. Kaplan–Meier survival curves were used to compare mortality among PAPP quartiles, and significance was tested using the log‐rank test.ResultsPatients in the lowest quartile (PAPP ≤0.47) had a significantly higher 5‐year mortality than did patients in higher quartiles (log‐rank P = 0.016). In a Cox model adjusted for the PHC equation, PAPP remained significantly associated with 5‐year mortality (hazard ratio: 0.74 per 0.10 increase in PAPP, 95% confidence interval: 0.61‐0.90). The χ2 statistic for the single PAPP covariate in this model was 8.8 (P = 0.003), which compared favorably with the χ2 statistic of 15.2 (P < 0.0001) for the multivariable PHC equation.ConclusionsPAPP, an index of ventricular‐arterial coupling, is independently associated with survival in World Health Organization group 1 PH. The use of this easily measurable index for guiding risk stratification needs further investigation.

Introduction: Pulmonary hypertension (PH) is a progressive disease with significant morbidity and mortality if specialized care is delayed. We sought to evaluate contemporary referral patterns and patient functional status at the time of initial referral to PH specialty clinic. Methods: We evaluated patient functional status and clinical characteristics at initial referral in the University of Virginia PH clinic. The relationship of PH groups based on World Health Organization (WHO) groups, functional capacity as measured by the 6-minute walk (6MW), and REVEAL risk score was assessed using the Kruskal-Wallis test. Results: Among 239 patients (age 62.3 ± 13.6 years, 31% female), there were similar number of low (n = 81, Reveal 0–7), intermediate (n = 74, Reveal 8–9), and high-risk (n = 77, Reveal ≥ 10) patients. The median Reveal scores among WHO groups were similar: Group 1: 6 (IQR 6–10); Group 2: 8 (IQR 7–10); Group 3: 8 (IQR 6–11); Group 4: 9 (8–10); Group 5: 8.5 (7–11); Multiple Groups: 9 (7–11) (P = .69). In contrast, the 6MW time decreased with increasing Reveal score (P < .0001): 281 m (IQR 228–339 m) in low-risk patients, 250m (IQR 185–305 m) in intermediate-risk patients, and 150 m (IQR 100-255m) in high risk patients. Conclusions: Early referral to PH specialty care remains low in the contemporary era. Concerted efforts should be aimed at raising awareness and care of PH patients.

Background: There is paucity of data addressing interventricular interactions and outcomes in heart failure (HF). Pulmonary to systemic pulse pressure ratio [(PS-PPR) = (pulmonary artery systolic pressure—pulmonary diastolic pressure)/(systemic systolic pressure—systemic diastolic pressure)] is an integrated index of interventricular contractile efficiency that we recently showed to be predictive of mortality in group 1 pulmonary hypertension. We tested the hypothesis that PS-PPR is associated with adverse outcomes in advanced HF using data from the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial. Methods: This was a retrospective analysis of 165 patients with complete variables for the calculation of PS-PPR at the end of hemodynamically guided therapy. We evaluated the association between PS-PPR and the composite outcome of death, need for left ventricular assist device (LVAD) and heart transplantation (Death + LVAD + Tx), or Death + LVAD + Tx plus heart failure hospitalization (Death + LVAD + Tx + HFH). Multivariable Cox proportional hazards regression and Kaplan-Meier analysis with the log-rank statistic were used to model PS-PPR and 6 month outcomes. Results: Among 165 patients (mean age 56.6 ± 13.7, 28.5% female), the median PS-PPR was 0.60 (IQR, 0.42–0.82). In the multivariable logistic regression analysis, increase in PS-PPR was associated with more than a two-fold increase in composite outcome of Death + LVAD + Tx (HR 2.41, 95% CI 0.99–5.84, P = .052), as well as composite of Death + LVAD + Tx + HFH (HR 1.97, 95% CI 1.03–3.76, P = .039). Kaplan-Meier curve evaluating the freedom from death/LVAD/heart transplant, stratified by PS-PPR above and below median (0.60), approached significance with log-rank statistic as demonstrated in figure. Conclusions: Pulmonary to systemic pulse pressure ratio, a marker of biventricular contractile efficiency, was independently associated with death, need for LVAD or heart transplant, and HF hospitalization. These findings support further study of this index for guiding risk stratification in advanced HF.

Background: Pulmonary hypertension (PH) is classified into 5 World Health Organization (WHO) groups based on clinical, pathological, hemodynamic and treatment characteristics. There is however overlap with some patients having multiple categories. We hypothesized that patients with multiple WHO groups will have higher costs. Methods: We evaluated hospital costs of care based on WHO groups during the one-year period from the initial referral to the University of Virginia PH clinic. Costs between groups were compared with the Kruskall-Wallis test, and multivariable linear regression was used to evaluate the relationship between 1-year costs and WHO group classification adjusted for age. Results: Among 239 patients (age 62.3 ± 13.6 years, 31% female), 199 were classified into a single WHO Group (Group 1: n = 45.7%; Group 2: 24.6%; Group 3: 14.6%; Group 4: 6.5%; Group 5: 8.6%), while 40 were classified into more than one WHO group. In the unadjusted analysis, median costs were higher in patients with multiple WHO classifications versus those with a single WHO classification ($5,469 versus $4,677), but the difference was not statistically significant (P = .57). However, in an age-adjusted linear regression model, there was a significant association between 1-year costs and whether patients were classified into multiple WHO groups or a single WHO group (standardized coefficient 0.15; P = .04). Conclusions: Age-adjusted one-year costs for patients followed in a pulmonary hypertension clinic in a tertiary academic medical center were significantly associated with whether patients had multiple WHO group classifications or a single WHO group classification.