Mortality risk as a function of the ratio of pulmonary trunk to ascending aorta diameter in patients with suspected coronary artery disease

A composite score based on cardiovascular parameters can predict the mortality risk of patients with newly diagnosed interstitial lung disease: A prospective observational study

BACKGROUND

It is crucial to identify factors that can predict the risk of mortality in patients newly diagnosed with interstitial lung disease (ILD). This study sought to develop and assess a composite scoring system for mortality prediction among ILD patients based on cardiovascular parameters, which were previously reported as predictors of survival.

METHODS

We prospectively enrolled patients with newly diagnosed ILD and monitored their survival status for 24 months. Surviving and deceased patients were compared regarding their baseline characteristics including clinical, pulmonary, and cardiovascular parameters. A system of composite scores was established based on significant cardiovascular parameters and the Gender-Age-Physiology (GAP) score. Receiver operating characteristic curves were generated to identify their optimal cut-off values. Univariate as well as multiple multivariate regression models were built to investigate the mortality prediction of different individual and combined parameters.

RESULTS

Ninety-six patients newly diagnosed with ILD underwent cardiovascular evaluation. In univariate analysis, three cardiovascular parameters were identified as significant predictors of mortality risk in ILD patients, either individually or as a combination of composite scores: tricuspid regurgitation velocity > 3.1 m/s; N-terminal pro-B-type natriuretic peptide level > 300 pg/ml and computed tomography pulmonary artery/ascending aorta diameter ratio > 0.9. In multivariate analysis, a composite score of those parameters [hazard ratio (HR) = 2.37 (confidence interval [CI]:1.06-5.33); p = 0.037; Score 1] and GAP score [HR = 1.62 (CI: 1.11-2.36); p = 0.012] were the most significant predictors for mortality among ILD patients. Combination of Score 1 and GAP score (Score 2) can increase the accuracy of survival predictions (area under the curve 0.83; p < 0.001).

CONCLUSIONS

A composite score based on cardiovascular parameters and the GAP score can be used to predict the risk of mortality of patients with ILD. Such a score achieved better diagnostic accuracy than the GAP score alone. Nevertheless, further larger-scale randomized controlled trials are required for evaluation of the newly proposed score and confirmation of our results.

Clinical Effect of Pulmonary Artery Diameter/Ascending Aorta Diameter Ratio on Left Ventricular Reverse Remodeling in Patients With Dilated Cardiomyopathy

BACKGROUND

Many patients with dilated cardiomyopathy (DCM) progress to heart failure (HF), although some demonstrate left ventricular (LV) reverse remodeling (LVRR), which is associated with better outcomes. The pulmonary artery diameter (PAD) to ascending aortic diameter (AoD) ratio has been used as a prognostic predictor in patients with HF, although this tool's usefulness in predicting LVRR remains unknown.Methods and Results:Data from a prospective observational study of 211 patients diagnosed in 2000-2020 with DCM were retrospectively analyzed. Sixty-nine patients with New York Heart Association class I or II HF were included. LVRR was observed in 23 patients (33.3%). The mean LV ejection fraction (29%) and LV end-diastolic dimension (64.5 mm) were similar in patients with and without LVRR. The PAD/AoD ratio was significantly lower in patients with LVRR than those without (81.4% vs. 92.4%, respectively; P=0.003). The optimal PAD/AoD cut-off value for detecting LVRR was 0.9 according to the receiver operating characteristic curve analysis. Multivariate analysis identified a PAD/AoD ratio ≥0.9 as an independent predictor of presence/absence of LVRR. Cardiac events were significantly more common in patients with a PAD/AoD ratio ≥0.9 than those with a ratio <0.9, after a median follow up of 2.5 years (log-rank, P=0.007).

CONCLUSIONS

The PAD/AoD ratio can predict LVRR in patients with DCM.

Prognostic value of main pulmonary artery diameter to ascending aorta diameter ratio in patients with advanced heart failure

OBJECTIVES AND BACKGROUND

In this study we assessed the prognostic value of main pulmonary artery diameter and its ratio to ascending aorta diameter (P/Ao ratio) in advanced heart failure patients.

METHODS

Patients with advanced heart failure who were candidates for heart transplantation were retrospectively evaluated. The clinical information, cardiac catheterisation results, and computed tomography images were gathered from institutional database system. The observed and predicted probabilities for survival were analysed in a nomogram.

RESULTS

The P/Ao ratio was found to be a strong predictor for MACE both in traditional multivariable Cox proportional hazard regression modelling (increase in P/Ao ratio per 2 SD, HR:2.72, 95% CI 1.14-6.48, p = 0.024) and ridge regression analysis (increase in P/Ao ratio per 2SD, HR:3.45, 95% CI 1.53-7.74, p = 0.003). Prediction model showed statistically significant correlation between the observed and predicted probabilities for 1-year survival.

CONCLUSION

In patients with advanced heart failure, computed tomography derived P/Ao ratio might be a prognostic predictor during follow up.

Nocturnal Hypoxemia and CT Determined Pulmonary Artery Enlargement in Smokers

Background: Pulmonary artery enlargement (PAE) detected using chest computed tomography (CT) is associated with poor outcomes in chronic obstructive pulmonary disease (COPD). It is unknown whether nocturnal hypoxemia occurring in smokers, with or without COPD, obstructive sleep apnoea (OSA) or their overlap, may be associated with PAE assessed by chest CT. Methods: We analysed data from two prospective cohort studies that enrolled 284 smokers in lung cancer screening programs and completing baseline home sleep studies and chest CT scans. Main pulmonary artery diameter (PAD) and the ratio of the PAD to that of the aorta (PA:Ao ratio) were measured. PAE was defined as a PAD ≥ 29 mm in men and ≥27 mm in women or as a PA:Ao ratio > 0.9. We evaluated the association of PAE with baseline characteristics using multivariate logistic models. Results: PAE prevalence was 27% as defined by PAD measurements and 11.6% by the PA:Ao ratio. A body mass index ≥ 30 kg/m² (OR 2.01; 95%CI 1.06–3.78), lower % predicted of forced expiratory volume in one second (FEV₁) (OR 1.03; 95%CI 1.02–1.05) and higher % of sleep time with O₂ saturation < 90% (T90) (OR 1.02; 95%CI 1.00–1.03), were associated with PAE as determined by PAD. However, only T90 remained significantly associated with PAE as defined by the PA:Ao ratio (OR 1.02; 95%CI 1.01–1.03). In the subset group without OSA, only T90 remains associated with PAE, whether defined by PAD measurement (OR 1.02; 95%CI 1.01–1.03) or PA:Ao ratio (OR 1.04; 95%CI 1.01–1.07). Conclusions: In smokers with or without COPD, nocturnal hypoxemia was associated with PAE independently of OSA coexistence.

Pulmonary artery to ascending aorta ratio by echocardiography: A strong predictor for presence and severity of pulmonary hypertension

BACKGROUND

The pulmonary artery (PA) to ascending aorta diameter ratio (PA:A) has been evaluated in numerous studies analyzing cardiac magnetic resonance (CMR) and computed tomography (CT) data. Previously, no transthoracic echocardiography (TTE) cutoffs have been published. We sought to evaluate (1) the feasibility to image the pulmonary trunk in a prospective cohort, and (2) the ability of PA:A derived by TTE to predict pulmonary hypertension (PH).

METHODS

We performed a post-hoc analysis of a prospectively recruited consecutive cohort of patients referred to our tertiary center cardiology department due to suspicion for PH. Invasive hemodynamic assessment and quasi-simultaneous TTE was performed in all participants.

RESULTS

A total of 84 patients were included in the analysis, median age was 70.5 years (IQR 58-75), 46 (55%) were female. The PA was significantly wider in the PH group (28mm vs. 22.5mm, p<0.001) with a resulting median PA:A of 0.84 vs. 0.66 (p<0.001). Both PA diameter (r = 0.524 and r = 0.44, both p<0.001) and PA:A (r = 0.652 and 0.697, both p<0.001) significantly correlated with mPAP and with PVR, respectively. Area under the curve for the detection of PH was 0.853 (95%CI 0.739-0.967, p<0.001).

CONCLUSION

The PA can be visualized in almost all echocardiographic exams, especially when it is dilated. A view showing the pulmonary trunk should be included in every routine TTE. An increased PA:A should raise suspicion for PH and prompt further evaluation and follow-up examinations of these patients.

Pulmonary artery enlargement is associated with pulmonary hypertension and decreased survival in severe cystic fibrosis: A cohort study

BACKGROUND

Pulmonary artery (PA) enlargement, defined as pulmonary artery to ascending aorta diameter ratio (PA:A)>1 on computed tomography (CT), is a marker of pulmonary vascular disease in chronic lung diseases. PA enlargement is prevalent in cystic fibrosis (CF), but its relationship to hemodynamics and prognostic utility in severe CF are unknown. We hypothesized that the PA:A would have utility in identifying pulmonary hypertension (PH) in severe CF and that PA enlargement would be associated with reduced transplant-free survival.

METHODS

We conducted a retrospective study of adults with CF undergoing lung transplant evaluation at a single center between 2000 and 2015. CT, right heart catheterization (RHC), and clinical data were collected. The PA:A was measured from a single CT slice. We measured associations between PA:A and invasive hemodynamic parameters including PH defined as a mPAP ≥25mmHg using adjusted linear and logistic regression models. Kaplan-Meier and adjusted Cox regression models were used to measure associations between PA:A>1, RHC-defined PH, and transplant-free survival in severe CF.

RESULTS

We analyzed 78 adults with CF that had CT scans available for review, including 44 that also had RHC. RHC-defined PH defined as a mPAP ≥25mmHg was present in 36% of patients with CF undergoing transplant evaluation. The PA:A correlated with mPAP (r = 0.73; 95% CI 3.87-7.80; p<0.001) and PVR (r = 0.42, p = 0.005) and the PA:A>1 was an independent predictor of PH (aOR 4.50; 95% CI 1.05-19.2; p = 0.042). PA:A>1 was independently associated with increased hazards for death or transplant (aHR 2.69; 95% CI 1.41-5.14; P = 0.003). The presence of mPAP ≥25mmHg was independently associated with decreased survival in this cohort.

CONCLUSIONS

PA enlargement is associated with pulmonary hemodynamics and PH in severe CF. PA enlargement is an independent prognostic indicator of PH and decreased survival in this population.

Clinical and prognostic relationships of pulmonary artery to aorta diameter ratio in patients with heart failure: a cardiac magnetic resonance imaging study

BACKGROUND

The pulmonary artery (PA) distends as pressure increases.

HYPOTHESIS

The ratio of PA to aortic (Ao) diameter may be an indicator of pulmonary hypertension and consequently carry prognostic information in patients with chronic heart failure (HF).

METHODS

Patients with chronic HF and control subjects undergoing cardiac magnetic resonance imaging were evaluated. The main PA diameter and the transverse axial Ao diameter at the level of bifurcation of the main PA were measured. The maximum diameter of both vessels was measured throughout the cardiac cycle and the PA/Ao ratio was calculated.

RESULTS

A total of 384 patients (mean age, 69 years; mean left ventricular ejection fraction, 40%; median NT-proBNP, 1010 ng/L [interquartile range, 448-2262 ng/L]) and 38 controls were included. Controls and patients with chronic HF had similar maximum Ao and PA diameters and PA/Ao ratio. During a median follow-up of 1759 days (interquartile range, 998-2269 days), 181 patients with HF were hospitalized for HF or died. Neither PA diameter nor PA/Ao ratio predicted outcome in univariable analysis. In a multivariable model, only age and NT-proBNP were independent predictors of adverse events.

CONCLUSIONS

The PA/Ao ratio is not a useful method to stratify prognosis in patients with HF.

Pulmonary artery to aorta ratio and risk of all-cause mortality in the general population: the Rotterdam Study

A pulmonary artery to aorta ratio (PA:A) >1 is a proxy of pulmonary hypertension. It is not known whether this measure carries prognostic information in the general population and in individuals with chronic obstructive pulmonary disease (COPD).

Between 2003 and 2006, 2197 participants from the population-based Rotterdam Study (mean±sd age 69.7±6.7 years; 51.3% female), underwent cardiac computed tomography (CT) scanning with PA:A quantification, defined as the ratio between the diameters of the pulmonary artery and the aorta. COPD was diagnosed based on spirometry or clinical presentation and obstructive lung function measured by a treating physician. Cox regression was used to investigate the risk of mortality.

We observed no association between 1-sd increase of PA:A and mortality in the general population. Larger PA:A was associated with an increased risk of mortality in individuals with COPD, particularly in moderate-to-severe COPD (hazard ratio 1.36, 95% CI 1.03–1.79). We demonstrated that the risk of mortality in COPD was driven by severe COPD, and that this risk increased with decreasing diffusing capacity.

Larger PA:A is not associated with mortality in an older general population, but is an independent determinant of mortality in moderate-to-severe COPD. Measuring PA:A in CT scans obtained for other indications may yield important prognostic information in individuals with COPD.

Pulmonary artery to aorta ratio is associated with cardiac structure and functional changes in mild-to-moderate COPD

Background

The ratio of the diameter of the pulmonary artery (PA) to the diameter of the aorta (PA:A) on computed tomography (CT) imaging is associated with both COPD exacerbation and pulmonary hypertension. The mechanisms of PA enlargement in COPD are poorly understood.

Methods

In this retrospective, single center study we evaluated pulmonary function, CT scans, right heart catheterizations, and echocardiography in 88 subjects with mild-to-moderately severe COPD. A sensitivity analysis was performed in 43 subjects in whom CT scan and echocardiogram were performed within 50 days of each other. To evaluate the association between PA:A ratio and echocardiographic parameters and hemodynamics, we performed simple correlations and multivariable linear regression analysis adjusting for lung function, age, sex, race, and diastolic function.

Results

All subjects had preserved left ventricular (LV) systolic function (LV ejection fraction 62.7%±5.5%). Among them, 56.8% had evidence of diastolic dysfunction. There was no association between PA:A ratio and the presence of diastolic dysfunction. In a multivariable model, PA:A ratio was associated with right ventricular (RV) chamber size (β=0.015; P<0.003), RV wall thickness (β=0.56; P<0.002), and RV function (−0.49; P=0.05). In the subgroup of subjects with testing within 50 days, the association with RV chamber size persisted (β=0.017; P=0.04), as did the lack of association with diastolic function. PA:A ratio was also associated with elevated PA systolic pressures (r=0.62; P=0.006) and pulmonary vascular resistance (r=0.46; P=0.05), but not pulmonary arterial wedge pressure (r=0.17; P=0.5) in a subset of patients undergoing right heart catheterization.

Conclusion

In patients with mild-to-moderately severe COPD and preserved LV function, increased PA:A ratio occurs independent of LV diastolic dysfunction. Furthermore, the PA:A ratio is associated with right heart structure and function changes, as well as pulmonary hemodynamics. These findings indicate that PA:A ratio is a marker of intrinsic pulmonary vascular changes rather than impaired LV filling.

Functional and Prognostic Implications of the Main Pulmonary Artery Diameter to Aorta Diameter Ratio from Chest Computed Tomography in Korean COPD Patients

BACKGROUND

The ratio of the diameter of the main pulmonary artery (mPA) to the diameter of the aorta (Ao) on chest computed tomography is associated with diverse clinical conditions. Herein, we determined the functional and prognostic implications of the mPA/Ao ratio in Korean chronic obstructive pulmonary disease (COPD) patients.

METHODS

The study population comprised 226 chronic obstructive pulmonary disease patients from the Korean Obstructive Lung Disease cohort who underwent chest computed tomography. We analyzed the relationships between the clinical characteristics, including pulmonary function, echocardiography findings, St. George's Respiratory Questionnaire, 6-minute walking (6MW) distance, and exacerbation with the mPA, Ao, and mPA/Ao ratio.

RESULTS

The mean age was 65.8 years, and 219 (96.9%) patients were male. The mean FEV1% predicted and FEV1/FVC ratio were 61.2% and 47.3%, respectively. The mean mPA and Ao were 23.7 and 36.4 mm, respectively, and the mPA/Ao ratio was 0.66. The mPA/Ao ratio correlated negatively with the 6MW distance (G = -0.133, P = 0.025) and positively with the right ventricular pressure (G = 0.323, P = 0.001). After adjustment for potential confounders, the mPA/Ao ratio was significantly associated with 6MW distance (β = -107.7, P = 0.017). Moreover, an mPA/Ao ratio >0.8 was a significant predictor of exacerbation at the 1-year (odds ratio 2.12, 95% confidence interval 1.27-3.52) and 3-year follow-ups (odds ratio 2.04, 95% confidence interval 1.42-2.90).

CONCLUSIONS

The mPA/Ao ratio is an independent predictor of exercise capacity and an mPA/Ao ratio >0.8 is a significant risk factor of COPD exacerbation.

Biomarkers of World Trade Center Particulate Matter Exposure: Physiology of Distal Airway and Blood Biomarkers that Predict FEV₁ Decline

Biomarkers can be important predictors of disease severity and progression. The intense exposure to particulates and other toxins from the destruction of the World Trade Center (WTC) overwhelmed the lung's normal protective barriers. The Fire Department of New York (FDNY) cohort not only had baseline pre-exposure lung function measures but also had serum samples banked soon after their WTC exposure. This well-phenotyped group of highly exposed first responders is an ideal cohort for biomarker discovery and eventual validation. Disease progression was heterogeneous in this group in that some individuals subsequently developed abnormal lung function while others recovered. Airflow obstruction predominated in WTC-exposed patients who were symptomatic. Multiple independent disease pathways may cause this abnormal FEV1 after irritant exposure. WTC exposure activates one or more of these pathways causing abnormal FEV1 in an individual. Our hypothesis was that serum biomarkers expressed within 6 months after WTC exposure reflect active disease pathways and predict subsequent development or protection from abnormal FEV1 below the lower limit of normal known as WTC-Lung Injury (WTC-LI). We utilized a nested case-cohort control design of previously healthy never smokers who sought subspecialty pulmonary evaluation to explore predictive biomarkers of WTC-LI. We have identified biomarkers of inflammation, metabolic derangement, protease/antiprotease balance, and vascular injury expressed in serum within 6 months of WTC exposure that were predictive of their FEV1 up to 7 years after their WTC exposure. Predicting future risk of airway injury after particulate exposures can focus monitoring and early treatment on a subset of patients in greatest need of these services.

Comparison of CT-Determined Pulmonary Artery Diameter, Aortic Diameter, and Their Ratio in Healthy and Diverse Clinical Conditions

BACKGROUND

The main pulmonary artery diameter (mPA), aortic diameter (Ao), and the mPA/Ao ratio, easily measured using chest computed tomography (CT), provide information that enables the diagnosis and evaluation of cardiopulmonary diseases. Here, we used CT to determine the sex- and age-specific distribution of normal reference values for mPA, Ao, and mPA/Ao ratio in an adult Korean population.

METHODS

Data from non-contrast, ECG-gated, coronary-calcium-scoring CT images of 2,547 individuals who visited the Health Screening Center of the Severance Hospital were analyzed. Healthy individuals (n = 813) included those who do not have hypertension, diabetes, asthma, obstructive lung disease, ischemic heart disease, stroke, smoking, obesity, and abnormal CT findings. Both mPA and Ao were measured at the level of bifurcation of the main pulmonary artery.

RESULTS

The mean mPA and Ao were 25.9 mm and 30.0 mm in healthy participants, respectively, while the mean mPA/Ao ratio was 0.87. Medical conditions associated with a larger mPA were male, obesity, smoking history, hypertension, and diabetes. A larger mPA/Ao ratio was associated with female, the obese, non-smoker, normotensive, and normal serum level of lipids, while a smaller mPA/Ao ratio was associated with older age. In healthy individuals, the 90th percentile sex-specific mPA, Ao, and mPA/Ao ratio were, 31.3 mm (95% CI 29.9-32.2), 36.8 mm (95% CI 35.7-37.5), and 1.05 (95% CI 0.99-1.07) in males, and 29.6 mm (95% CI 29.1-30.2), 34.5 mm (95% CI 34.1-34.9), and 1.03 (95% CI 1.02-1.06) in females, respectively.

CONCLUSION

In the Korean population, the mean mPA reference values in male and female were 26.5 mm and 25.8 mm, respectively, while the mean mPA/Ao ratio was 0.87. These values were influenced by a variety of underlying medical conditions.

Enlarged pulmonary artery is predicted by vascular injury biomarkers and is associated with WTC-Lung Injury in exposed fire fighters: a case-control study

OBJECTIVES

We hypothesise that there is an association between an elevated pulmonary artery/aorta (PA/A) and World Trade Center-Lung Injury (WTC-LI). We assessed if serum vascular disease biomarkers were predictive of an elevated PA/A.

DESIGN

Retrospective case-cohort analysis of thoracic CT scans of WTC-exposed firefighters who were symptomatic between 9/12/2001 and 3/10/2008. Quantification of vascular-associated biomarkers from serum collected within 200 days of exposure.

SETTING

Urban tertiary care centre and occupational healthcare centre.

PARTICIPANTS

Male never-smoking firefighters with accurate pre-9/11 forced expiratory volume in 1 s (FEV1)≥75%, serum sampled ≤200 days of exposure was the baseline cohort (n=801). A subcohort (n=97) with available CT scans and serum biomarkers was identified. WTC-LI was defined as FEV1≤77% at the subspecialty pulmonary evaluation (n=34) and compared with controls (n=63) to determine the associated PA/A ratio. The subcohort was restratified based on PA/A≥0.92 (n=38) and PA/A<0.92(n=59) to determine serum vascular biomarkers that were predictive of this vasculopathy.

OUTCOME MEASURES

The primary outcome of this study was to identify a PA/A ratio in a cohort of individuals exposed to WTC dust that was associated with WTC-LI. The secondary outcome was to identify serum biomarkers predictive of the PA/A ratio using logistic regression.

RESULTS

PA/A≥0.92 was associated with WTC-LI, OR of 4.02 (95% CI 1.21 to 13.41; p=0.023) when adjusted for exposure, body mass index and age at CT. Elevated macrophage derived chemokine and soluble endothelial selectin were predictive of PA/A≥0.92, (OR, 95% CI 2.08, 1.05 to 4.11, p=0.036; 1.33, 1.06 to 1.68, p=0.016, respectively), while the increased total plasminogen activator inhibitor 1 was predictive of not having PA/A≥0.92 (OR 0.88, 0.79 to 0.98; p=0.024).

CONCLUSIONS

Elevated PA/A was associated with WTC-LI. Development of an elevated PA/A was predicted by biomarkers of vascular disease found in serum drawn within 6 months of WTC exposure. Increased PA/A is a potentially useful non-invasive biomarker of WTC-LI and warrants further study.

Pathophysiology and clinical implications of pulmonary arterial enlargement in COPD

Chronic obstructive pulmonary disease (COPD) is a complex condition defined by progressive airflow limitation in response to noxious stimuli, inflammation, and vascular changes. COPD exacerbations are critical events in the natural history of the disease, accounting for the majority of disease burden, cost, and mortality. Pulmonary vascular disease is an important risk factor for disease progression and exacerbation risk. Relative pulmonary artery enlargement on computed tomography scan, defined by a pulmonary artery to aortic (PA:A) ratio >1, has been evaluated as a marker of pulmonary vascular disease. The PA:A ratio can be measured reliably independent of electrocardiographic gating or the use of contrast, and in healthy patients a PA:A ratio >0.9 is considered to be abnormal. The PA:A ratio has been compared with invasive hemodynamic parameters, primarily mean pulmonary artery pressure in various disease conditions and is more strongly correlated with mean pulmonary artery pressure in obstructive as compared with interstitial lung disease. In patients without known cardiac or pulmonary disease, the PA:A ratio is predictive of mortality, while in COPD, an elevated PA:A ratio is correlated with increased exacerbation risk, outperforming other well established predictors of these events. Future studies should be aimed at determining the stability of the metric over time and evaluating the utility of the PA:A ratio in guiding specific therapies.