The effects of bolus isosorbide dinitrate on pulmonary hypertension with cardiopulmonary comorbidities.

Lowering mean pulmonary arterial pressure (mPAP) without reducing cardiac output is essential in treating pulmonary hypertension (PH). Isosorbide dinitrate (ISDN) potentially achieves this in post-capillary PH but can decrease cardiac output and blood pressure (BP), especially in pre-capillary PH. However, post-capillary PH and pre-capillary PH can overlap, and their clear discrimination is difficult. The aim of the study was to examine to what extent bolus ISDN injection reduces mPAP and BP, and changes mixed venous oxygen saturation (SvO2), an indicator of cardiac output in PH with various cardiopulmonary comorbidities in the context of treatment modifications. We retrospectively examined the hemodynamic effects of bolus ISDN injection in patients with PH who underwent right heart catheterization and their subsequent treatment modification. Our sample comprised 13 PH patients. In seven with pre-capillary PH, ISDN significantly lowered mPAP from the median 34 (interquartile range 32-39) to 28 (28-30) mmHg and the mean BP (mBP) from 90 (79-92) to 72 (68-87) mmHg. In six with post-capillary PH, ISDN lowered mPAP from 40 (29-44) to 27 (23-31) mmHg and mBP from 91 (87-110) to 87 (82-104) mmHg. There was a significant decrease in SvO2 from 69.8% (64.9%-78.1%) to 63.9% (60.5%-71.5%) in pre-capillary PH, but not in post-capillary PH including combined post- and pre-capillary PH and some patients showed a large increase in SvO2. In all patients showing an SvO2 increase, diuretics or hemodialysis were up-titrated or continued. Bolus ISDN injection lowered mPAP. However, in pre-capillary PH, it caused a significant decrease in SvO2 and a notable reduction in blood pressure. In post-capillary PH, including combined post- and pre-capillary PH, it clarified whether systemic preload and afterload reduction increased or decreased SvO2 in each patient, which may aid in treatment modification.

Pulmonary vascular disease in pulmonary hypertension due to left heart disease: pathophysiologic implications.

AIMS: Pulmonary hypertension (PH) and pulmonary vascular disease (PVD) are common and associated with adverse outcomes in left heart disease (LHD). This study sought to characterize the pathophysiology of PVD across the spectrum of PH in LHD. METHODS AND RESULTS: Patients with PH-LHD [mean pulmonary artery (PA) pressure >20 mmHg and PA wedge pressure (PAWP) ≥15 mmHg] and controls free of PH or LHD underwent invasive haemodynamic exercise testing with simultaneous echocardiography, expired air and blood gas analysis, and lung ultrasound in a prospective study. Patients with PH-LHD were divided into isolated post-capillary PH (IpcPH) and PVD [combined post- and pre-capillary PH (CpcPH)] based upon pulmonary vascular resistance (PVR <3.0 or ≥3.0 WU). As compared with controls (n = 69) and IpcPH-LHD (n = 55), participants with CpcPH-LHD (n = 40) displayed poorer left atrial function and more severe right ventricular (RV) dysfunction at rest. With exercise, patients with CpcPH-LHD displayed similar PAWP to IpcPH-LHD, but more severe RV-PA uncoupling, greater ventricular interaction, and more severe impairments in cardiac output, O2 delivery, and peak O2 consumption. Despite higher PVR, participants with CpcPH developed more severe lung congestion compared with both IpcPH-LHD and controls, which was associated lower arterial O2 tension, reduced alveolar ventilation, decreased pulmonary O2 diffusion, and greater ventilation-perfusion mismatch. CONCLUSIONS: Pulmonary vascular disease in LHD is associated with a distinct pathophysiologic signature marked by greater exercise-induced lung congestion, arterial hypoxaemia, RV-PA uncoupling, ventricular interdependence, and impairment in O2 delivery, impairing aerobic capacity. Further study is required to identify novel treatments targeting the pulmonary vasculature in PH-LHD.

Long-term survival outcome for pre-capillary pulmonary hypertension at a Japanese single center.

In recent years, several treatment options for patients with pre-capillary pulmonary hypertension (PH) have improved the short-term prognosis. However, the long-term survival for pre-capillary PH has not been well investigated. This study sought to investigate the long-term survival for pre-capillary PH in Kurume University Hospital. A total of 144 patients with pre-capillary PH (110 women, mean age 55.1 ± 17.9 years) were enrolled. The maximal duration of followup was 15 years with a mean followup of 5.77 years. The 15 year survival was 59.1% for pre-capillary PH, 68.5% for pulmonary arterial hypertension (PAH), and 44.3% for chronic thromboembolic PH. The 5 year survival was 50.9% for PH due to lung disease (PH-LD), indicating the worst in the pre-capillary PH subgroups. The survival for portopulmonary hypertension was the lowest among PAH groups, and PAH associated with connective tissue disease and congenital heart disease decreased 10 years after diagnosis. A 6 min walk distance and elevated brain natriuretic peptide were significantly associated with survival outcome in pre-capillary PH patients and diastolic pulmonary arterial pressure was related to survival for PH-LD. The survivals were different among pre-capillary PH groups in our hospital. Above all, the long-term survival was better than in previous reports.

Right Ventricular Stroke Work Index.

Recently, long-term outcomes of pre-capillary pulmonary hypertension (PH) have been improved, whereas morbidity and mortality are still high because of right-sided heart failure (HF). Right-sided HF is closely related to right ventricular (RV) function and hemodynamics such as RV stroke work index (RVSWI). However, the association between RVSWI and long-term outcomes in pre-capillary PH has not been well investigated. The aims of this study were to compare clinical characteristics between low RVSWI and high RVSWI and to investigate the association between low RVSWI and long-term outcomes in patients with pre-capillary PH. We included patients admitted to diagnose and evaluate PH by right heart catheterization between 2007 and 2015. Patients with pre-capillary PH were divided into two groups according to the median value of RVSWI (low RVSWI group: RVSWI < 19.7 g・m/m2/beat; high RVSWI group: RVSWI ≥ 19.7 g・m/m2/beat). Kaplan-Meier survival curves were applied to investigate whether the low RVSWI were associated with HF death or HF readmission in patients with pre-capillary PH. A total of 36 patients with pre-capillary PH who were diagnosed as pulmonary arterial hypertension (PAH) or chronic thromboembolic PH (CTEPH) were allocated into the low RVSWI group (n = 18) and high RVSWI group (n = 18). The event-free survival rate was significantly lower in the low RVSWI group as compared with the high RVSWI group (P = 0.02). In conclusion, lower RVSWI was significantly associated with HF death or HF readmission in patients with PAH or CTEPH.

Left heart abnormalities in connective tissue disease patients with pre-capillary pulmonary hypertension as well as borderline mean pulmonary arterial pressure.

OBJECTIVE: To describe co-existence of left heart abnormalities among case series of connective tissue disease (CTD) patients who showed pre-capillary pulmonary hypertension (PH) as well as borderline mean pulmonary arterial pressure (mPAP). METHODS: From 2010 through 2012, 49 CTD patients suspected to have PH by exercise Doppler echocardiography underwent right heart catheterization. We retrospectively searched for left heart diseases from the available data on Doppler echocardiography, cardiac magnetic resonance imaging (MRI), scintigraphy, and endomyocardial biopsy. RESULTS: Among 49 patients, 11 and 2 had pre- and post-capillary PH, respectively, and another 10 had borderline mPAP. Six of 11 patients with pre-capillary PH showed low pulmonary vascular resistance (PVR) (≤ 240 dynes•sec•cm(- 5)) and low diastolic pulmonary gradient (< 7 mmHg). Seven of 10 patients with borderline mPAP had normal PVR (< 160) suggesting the presence of left heart abnormalities. Other abnormal findings included increased left atrial volume index and E/E' on Doppler echocardiography, delayed contrast enhancement by MRI, patchy area of hypoperfusion on thallium scintigraphy, and fibrosis in endomyocardial biopsy. CONCLUSION: The present case series suggested some contribution of left heart abnormalities to the increase in mPAP among CTD patients with pre-capillary PH as well as borderline mPAP.

Association of arteriovenous fistulae with precapillary pulmonary hypertension - A single center retrospective analysis of invasive hemodynamic parameters.

BACKGROUND: Pulmonary hypertension (pH) is a well-known complication among patients with chronic kidney disease (CKD). Arteriovenous fistulae (AVF) have been associated with pH mainly by increasing cardiac output. However, the burden of precapillary pH in individuals with CKD and an AVF is unclear. OBJECTIVES: To better and more fully understand the mechanism and development of precapillary pH in patients with AVF, as well as the consequences of precapillary pH in these patients. METHODS: This was a large retrospective study of patients with CKD stage 4 or 5 who underwent right heart catheterization (RHC) from 2018 to 2023. The data were stratified according to the presence of AVF. To determine if AVF was independently associated with precapillary pH, we used a multivariable logistic regression analysis adjusting for demographics and potential comorbidities associated with precapillary pH, including diagnosis of chronic lung disease, obstructive sleep apnea, connective tissue disease, history of venous thromboembolism, chronic anemia, and heart failure. RESULTS: Of 651 patients with CKD4 or CKD5, 145 (22 %) had AVF and 506 (78 %) did not have AVF. Within the AVF group, the median age was 64 years (IQR 54-71), and they were predominantly males (61 %, n = 88) and African American (77 %, n = 111). A total of 31 % (n = 45) had evidence of precapillary pH, 30 % (n = 43) of combined pH, and 14 % (n = 20) of isolated postcapillary pH. Compared to the non-AVF group, precapillary pH was more likely in the AVF group (31% vs 17 %, p < 0.0001). On multivariable analysis, AVF was independently associated with precapillary pH (OR 2.47, CI 1.56-3.89; p < 0.0001). The median time from dialysis initiation to RHC date (and precapillary pH diagnosis) was 6 years (IQR 3-8). CONCLUSION: Based on RHC findings, almost one-third of patients with CKD and AVF had precapillary pH. The presence of AVF was independently associated with precapillary pH.

Clinical Characteristics and Outcomes Associated With Distinct Hemodynamic Patterns in End-stage Liver Disease: A Retrospective Cohort Analysis.

Introduction: Despite advances in the diagnosis and therapeutics strategies for pulmonary hypertension (PH) in patients with end-stage liver disease (ESLD), the impact of hemodynamic patterns among ESLD patients identified through right heart catheterization (RHC) on clinical outcomes remains poorly understood. Methods: This single-center retrospective cohort study identified patients diagnosed with ESLD who underwent RHC from August 2018 to June 2023. Demographic and clinical data, including comorbidities, transthoracic echocardiography, and RHC findings, were obtained. Our outcomes of interest were all-cause mortality and the chance of receiving orthotopic liver transplantation (OLT) within a year after RHC. Kaplan-Meier with log-rank test was employed to generate survival curves. Results: We identified 415 ESLD patients with the RHC results. The median (IQR) age was 59 years (52-66), and 62% were male. Caucasians accounted for 43%, followed by African Americans (30%). Up to 89% had a diagnosis of portal hypertension. Median MELD-Na score was 30 (19-36). The etiology of ESLD was mainly from alcohol use (55%). Patients were classified based on RHC results as pre-capillary PH (19%), post-capillary PH (28%), and non-PH (53%) groups. Overall, one-year mortality post-RHC was 22%, with no significant difference in mortality regardless of hemodynamic group. However, the pre-capillary PH group was less likely to receive OLT compared to other groups (P < 0.001). Conclusion: We observed no difference in all-cause mortality among hemodynamic groups. However, pre-capillary PH group were less likely to undergo OLT compared to others. Further investigations are necessary to determine how this should be addressed in clinical practice.

Pulmonary hypertension across the spectrum of left heart and lung disease.

AIMS: Patients with pulmonary hypertension (PH) are grouped based upon clinical and haemodynamic characteristics. Groups 2 (G2, left heart disease [LHD]) and 3 (G3, lung disease or hypoxaemia) are most common. Many patients display overlapping characteristics of heart and lung disease (G2-3), but this group is not well-characterized. METHODS AND RESULTS: Patients with PH enrolled in the prospective, NHLBI-sponsored PVDOMICS network underwent intensive clinical, biomarker, imaging, gas exchange and exercise phenotyping. Patients with pure G2, pure G3, or overlapping G2-3 PH were compared across multiple phenotypic domains. Of all patients with predominant G2 (n = 136), 66 (49%) were deemed to have secondary lung disease/hypoxaemia contributors (G2/3), and of all patients categorized as predominant G3 (n = 172), 41 (24%) were judged to have a component of secondary LHD (G3/2), such that 107 had G2-3 (combined G2/3 and G3/2). As compared with G3, patients with G2 and G2-3 were more obese and had greater prevalence of hypertension, atrial fibrillation, and coronary disease. Patients with G2 and G2-3 were more anaemic, with poorer kidney function, more cardiac dysfunction, and higher N-terminal pro-B-type natriuretic peptide than G3. Lung diffusion was more impaired in G3 and G2-3, but commonly abnormal even in G2. Exercise capacity was severely and similarly impaired across all groups, with no differences in 6-min walk distance or peak oxygen consumption, and pulmonary vasoreactivity to nitric oxide did not differ. In a multivariable Cox regression model, patients with G2 had lower risk of death or transplant compared with G3 (hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.30-0.86), and patients with G2-3 also displayed lower risk compared with G3 (HR 0.57, 95% CI 0.38-0.86). CONCLUSIONS: Overlap is common in patients with a pulmonary or cardiac basis for PH. While lung structure/function is clearly more impaired in G3 and G2-3 than G2, pulmonary abnormalities are common in G2, even when clinically judged as isolated LHD. Further study is required to identify optimal systematic evaluations to guide therapeutic innovation for PH associated with combined heart and lung disease. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT02980887.

Long-term outcome of patients with combined post- and pre-capillary pulmonary hypertension.

Aims: Pulmonary hypertension (PH) is a complex clinical condition, and left heart disease is the leading cause. Little is known about the epidemiology and prognosis of combined post- and pre-capillary PH (CpcPH). Methods and results: This retrospective analysis of the Swiss PH Registry included incident patients with CpcPH registered from January 2001 to June 2019 at 13 Swiss hospitals. Patient baseline characteristics [age, sex, mean pulmonary artery pressure (mPAP), pulmonary artery wedge pressure (PAWP), pulmonary vascular resistance (PVR), and risk factors, including World Health Organization (WHO)-functional class (FC), 6 min walk distance (6MWD), and N-terminal pro-brain natriuretic peptide (NT-proBNP), treatment, days of follow-up, and events (death or loss to follow-up) at last visit] were analysed by Kaplan-Meier and Cox regression analyses. Two hundred and thirty-one patients (59.3% women, age 65 ± 12 years, mPAP 48 ± 11 mmHg, PAWP 21 ± 5 mmHg, PVR 7.2 ± 4.8 WU) were included. Survival analyses showed a significantly longer survival for women [hazard ratio (HR) 0.58 (0.38-0.89); P = 0.01] and a higher mortality risk for mPAP > 46 mmHg [HR 1.58 (1.03-2.43); P = 0.04] but no association with age or PVR. Patients stratified to high risk according to four-strata risk assessment had an increased mortality risk compared with patients stratified to low-intermediate risk [HR 2.44 (1.23-4.84); P = 0.01]. A total of 46.8% of CpcPH patients received PH-targeted pharmacotherapy; however, PH-targeted medication was not associated with longer survival. Conclusion: Among patients with CpcPH, women and patients with an mPAP ≤46 mmHg survived longer. Furthermore, risk stratification by using non-invasively assessed risk factors, such as WHO-FC, 6MWD, and NT-proBNP, as proposed for pulmonary arterial hypertension, stratified survival in CpcPH, and might be helpful in the management of these patients.

MRI Feature Tracking Strain in Pulmonary Hypertension: Utility of Combined Left Atrial Volumetric and Deformation Assessment in Distinguishing Post- From Pre-capillary Physiology.

Aims: Pulmonary hypertension (PH) is dichotomized into pre- and post-capillary physiology by invasive catheterization. Imaging, particularly strain assessment, may aid in classification and be helpful with ambiguous hemodynamics. We sought to define cardiac MRI (CMR) feature tracking biatrial peak reservoir and biventricular peak systolic strain in pre- and post-capillary PH and examine the performance of peak left atrial strain in distinguishing the 2 groups compared to TTE. Methods and Results: Retrospective cross-sectional study from 1 Jan 2015 to 31 Dec 2020; 48 patients (22 pre- and 26 post-capillary) were included with contemporaneous TTE, CMR and catheterization. Mean pulmonary artery pressures were higher in the pre-capillary cohort (55 ± 14 vs. 42 ± 9 mmHg; p < 0.001) as was pulmonary vascular resistance (median 11.7 vs. 3.7 WU; p < 0.001). Post-capillary patients had significantly larger left atria (60 ± 22 vs. 25 ± 9 ml/m2; p < 0.001). There was no difference in right atrial volumes between groups (60 ± 21 vs. 61 ± 29 ml/m2; p = 0.694), however peak RA strain was lower in post-capillary PH patients (8.9 ± 5.5 vs. 18.8 ± 7.0%; p < 0.001). In the post-capillary group, there was commensurately severe peak strain impairment in both atria (LA strain 9.0 ± 5.8%, RA strain 8.9 ± 5.5%). CMR LAVi and peak LA strain had a multivariate AUC of 0.98 (95% CI 0.89-1.00; p < 0.001) for post-capillary PH diagnosis which was superior to TTE. Conclusion: CMR volumetric and deformation assessment of the left atrium can highly accurately distinguish post- from pre-capillary PH.

Beneficial Effects of Pulmonary Vasodilators on Pre-Capillary Pulmonary Hypertension in Patients with Chronic Kidney Disease on Hemodialysis.

BACKGROUND: In patients with chronic kidney disease (CKD) on hemodialysis, comorbid pulmonary hypertension (PH) aggravates exercise tolerance and eventually worsens the prognosis. The treatment strategy for pre-capillary PH, including combined pre- and post-capillary PH (Cpc-PH), has not been established. OBJECTIVES: This study aimed to evaluate the impact of pulmonary vasodilators on exercise tolerance and pulmonary hemodynamics in patients with CKD on hemodialysis. METHODS AND RESULTS: The medical records of 393 patients with suspected PH who underwent right heart catheterization were reviewed. Of these, seven patients had isolated pre-capillary PH and end-stage CKD on hemodialysis. Pulmonary vasodilators decreased pulmonary vascular resistance from 5.9 Wood units (interquartile range (IQR), 5.5-7.6) at baseline to 3.1 Wood units (IQR, 2.6-3.3) post-treatment (p = 0.02) as well as increased pulmonary capillary wedge pressure from 10 mmHg (IQR, 7-11) to 11 mmHg (IQR, 8-16) (p = 0.04). Pulmonary vasodilators increased the World Health Organization functional class I or II from 0% to 100% (p = 0.0002) and the 6 min walk distance from 273 m (IQR, 185-365) to 490 m (IQR, 470-550) (p = 0.03). CONCLUSIONS: Pulmonary vasodilators for PH in patients with CKD on hemodialysis decrease pulmonary vascular resistance and eventually improve exercise tolerance. Pulmonary vasodilators may help hemodialysis patients with pre-capillary PH, although careful management considering the risk of pulmonary edema is required.

Diagnosis and management of combined post- and precapillary pulmonary hypertension in a patient with multiple comorbidities.

Diagnosis of pulmonary hypertension requires a laborious investigation that must be performed in accordance with international guidelines. Right-heart catheterization is the gold standard examination to assess the degree of hemodynamic impairment of post- or precapillary origin, guiding management. The presence of comorbidities is becoming rather frequent in real-life pulmonary hypertension cases, thus creating diagnostic and therapeutic complexity. We present a case of combined post- and precapillary pulmonary hypertension in a patient with ischemic heart disease and combined pulmonary fibrosis and emphysema, in order to describe the diagnostic algorithm for pulmonary hypertension and elucidate the problematic aspects of managing this debilitating disease in a patient with several comorbidities. Current guidelines do not support the use of specific vasodilator treatment in group II - due to heart disease and group III-due to lung disease pulmonary hypertension, unless the patient presents with severe pulmonary hypertension (mean pulmonary artery pressure > 35 mm Hg or cardiac index < 2.0 L/min) with right ventricular dysfunction and is treated in an expert center and preferably in the context of a randomized control trial. In the case presented, therapeutic management focused, firstly, on treatment of the underlying heart and lung disease and, subsequently, on specific vasoactive therapy, due to severe hemodynamic deterioration.

Impact of the new definition of pulmonary hypertension according to world symposium of pulmonary hypertension 2018 on diagnosis of post-capillary pulmonary hypertension.

BACKGROUND: The World Symposium on Pulmonary Hypertension (WSPH) in 2018 recommended new definitions of pulmonary hypertension (PH). We investigated the impact of the updated definition on prevalence of PH due to left heart disease (PH-LHD). METHODS: The data of right heart catheterizations in patients with suspected PH-LHD between January 2008 and July 2015 was retrospectively analyzed applying different definitions. The number of patients diagnosed by the updated WSPH hemodynamic criteria of a mean pulmonary artery pressure (mPAP) > 20 mmHg was compared to the number of patients using mPAP ≥ 25 mmHg. The differentiation between patients with isolated post-capillary (Ipc) and combined post-capillary and pre-capillary (Cpc) PH was analyzed comparing the ESC/ERS guidelines, the recommendation of Cologne Consensus Conference (CCC) and WSPH. RESULTS: Of the 726 patients with a suspected PH, 58 patients met the diagnostic criteria of the ESC/ERS guidelines for PH-LHD with 32.8% Ipc-cases, 34.4% Cpc-PH-cases and 32.8% unclassifiable cases. Overall, 58 patients were diagnosed by the CCC criteria, with 34.5% classified as Cpc-PH and 65.5% as Icp-PH. Using the criteria of WSPH, the number of PH-LHD rose by one patient. According to the new definition, 64.4% of the patients were classified as Cpc-PH and had a significantly higher right to left atrial area (RA/LA) ratio than Ipc-PH patients. CONCLUSION: Applying the new recommendation, the number of diagnosed patients with PH-LHD increases marginally. There is, however, a relevant shift in the number of Cpc-PH cases. An elevated RA/LA ratio might help to identify patients for invasive diagnostic work-up.

Role of 3D echocardiography-determined atrial volumes in distinguishing between pre-capillary and post-capillary pulmonary hypertension.

AIMS: The current guidelines on pulmonary hypertension (PH) recommend the use of invasive examination for differentiating between left-sided heart disease-related (post-capillary) and pre-capillary PH. However, atrial sizes are considered markers of ventricular filling pressures. Therefore, we aimed to test the clinical applicability of atrial volumes measured by transthoracic three-dimensional echocardiography (3DE) in differentiating between pre-capillary and post-capillary PH. METHODS AND RESULTS: Seventy-five consecutive patients with PH were prospectively examined with transthoracic 3DE. After less than 24 h, the patients underwent right heart catheterization and 3DE and were classified as pre-capillary or post-capillary PH according to the recommendations of the ESC guidelines. The atrial volumes were measured offline with dedicated commercial software. Thirty-eight patients (13 men, age 65 ± 18 year) had pre-capillary PH, and 37 (23 men, age 62 ± year) had post-capillary PH. The mean pulmonary artery pressures were similar in patients with pre-capillary and post-capillary PH (38 [IQR 26, 54] mmHg vs. 41 [IQR 33, 48] mmHg, respectively, P = 0.49). The left atrial indexed maximum (LAVi max) and minimum (LAVi min) volumes were significantly larger in the post-capillary PH patient group than in the pre-capillary PH patient group (LAVi max: 64 ± 32 mL/m2 vs. 41 ± 25 mL/m2 , P = 0.001; LAVi min: 50 ± 22 mL/m2 vs. 26 ± 24 mL/m2 , P < 0.0001). The indexed right atrial minimum volume (RAVi min) was also higher in patients with post-capillary PH (51 ± 27 mL/m2 vs. 38 ± 26 mL/m2 ; P = 0.02). Both the left atrial (LA) and right atrial (RA) volumes, especially the LA minimum volume, correlated with the pulmonary artery wedge pressure (PAWP) (r = 0.62 (P < 0.0001) for LAV min vs. r = 0.49 (P < 0.0001) for LAV max; r = 0.32 (P = 0.005) for RAV min vs. r = 0.24 (P = 0.04) for RAV max). Multivariate logistic regression analysis showed that LAVi min was an independent predictor of post-capillary PH. In the receiver operating characteristic (ROC) curves of parameters predicting the post-capillary PH, the areas under the curve (AUC) for LAVi min, LAVi max, and RAVi min were 0.86 (95% CI, 0.76-0.95), 0.78 (95% CI, 0.67-0.89), and 0.66 (0.53-0.78), respectively. Concerning the performance of the atrial volume ratio for differentiating post-capillary PH, the AUC of the atrial volume ratio was significantly lower [AUC: 0.66 (95% CI, 0.53-0.78)]. The ROC analysis indicated a possible cutoff value of 27.7 mL/m2 for LAVi min to predict post-capillary PH (AUC = 0.86; sensitivity = 86%, specificity = 76%). CONCLUSIONS: The BSA-indexed left atrial minimum volume measured by transthoracic 3DE is a useful parameter for differentiating pre-capillary from post-capillary pulmonary hypertension.

Pulmonary Vascular Resistance Estimated by Echocardiography in Dogs With Myxomatous Mitral Valve Disease and Pulmonary Hypertension Probability.

Post-capillary pulmonary hypertension (PH) is a life-threatening complication in dogs with myxomatous mitral valve disease (MMVD). An increase in pulmonary vascular resistance (PVR) is associated with post-capillary PH progression. In humans, PVR estimated by echocardiography (PVRecho) enables the non-invasive assessment of PVR in patients with PH. This study aimed to evaluate the clinical utility of PVRecho in dogs with MMVD, PH probability, and right-sided congestive heart failure (R-CHF). Dogs with MMVD and detectable tricuspid valve regurgitation were included in the study. Dogs were classified into three PH probability groups (low/intermediate/high) and according to the presence or absence of R-CHF. All dogs underwent echocardiographic measurements for right ventricular (RV) morphology and function. PVRecho was calculated by two methods using tricuspid valve regurgitation velocity and velocity-time integral of the pulmonary artery flow (PVRecho and PVRecho2). RV size indicators were significantly higher with a higher probability of PH. RV strain and velocity-time integral of the pulmonary artery flow in the high probability group were significantly lower than those in the other groups. Tricuspid valve regurgitation velocity, PVRecho, and PVRecho2 were significantly higher with an increase in PH probability. Logistic regression analysis revealed a significant association between the presence of R-CHF and increased PVRecho2 and end-diastolic RV internal dimension normalized by body weight. PVRecho and PVRecho2 showed significant differences among the PH probability groups. These non-invasive variables may be useful for the diagnosis and stratification of PH and the determination of the presence of R-CHF in dogs with MMVD.

The predictive value of minute ventilation versus carbon dioxide production in pulmonary hypertension associated with left heart disease.

BACKGROUND: The aim of the present study was to investigate the role of key cardiopulmonary exercise testing (CPET) parameters in the identification of pre-capillary components in patients with pulmonary hypertension associated with left heart disease (PH-LHD), and to evaluate their correlations with hemodynamic parameters. METHODS: Ninety patients with PH-LHD underwent right-heart catheterization, echocardiography, and CPET. The differences in related indexes between a combined post- and pre-capillary PH (Cpc-PH) group (n=47) and an isolated post-capillary PH (Ipc-PH) group (n=43) were compared. Correlation analysis was performed. Logistic regression and receiver operator characteristic (ROC) analyses were performed to assess the ability of CPET variables to distinguish patients with Cpc-PH from those with Ipc-PH. RESULTS: The hemodynamics, hyperventilation and right ventricular function of Cpc-pH group were worse than those of Ipc-pH group. The parameters related to minute ventilation versus carbon dioxide production (VE/VCO2) played a significant role in the differentiation of Cpc-PH and Ipc-PH, and had a moderate positive correlation with pulmonary vascular resistance (PVR). Univariate and multivariate logistic analyses showed that lowest percentage of VE/VCO2 in predicted value (VE/VCO2%pred) was the single best predictor of Cpc-PH, and the area under ROC curve also confirmed that lowest VE/VCO2%pred (≥137%) could serve as a novel diagnostic marker for Cpc-PH. On the basis of this lowest VE/VCO2%pred threshold, patients were divided into two groups. Most hemodynamic parameters were worse in patients with a lowest VE/VCO2%pred ≥137%. CONCLUSIONS: VE/VCO2-related parameters are powerful prognosticators for the presence of pre-capillary components in patients with PH-LHD, especially lowest VE/VCO2%pred.

Ventilatory power, a cardiopulmonary exercise testing parameter for the prediction of pulmonary hypertension at right heart catheterization.

BACKGROUND: Several cardiopulmonary exercise test (CPET) parameters (peak VO2, PetCO2 and VE/VCO2) emerged as tools for the prediction of pulmonary arterial hypertension (PAH). Less is known on ventilatory power (VP) in patients with suspect PAH. AIM: To ascertain possible correlations between VP derived at CPET and hemodynamic parameters at right heart catheterization (RHC) indicative of PH. METHODS: Forty-seven consecutive outpatients with suspect of PAH were assessed by CPET and RHC; VP was defined as peak SBP divided by the minute ventilation-CO2 production slope at CPET and Diastolic Pressure Gradient (DPG), Trans-pulmonary Pressure Gradient (TPG), mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) at RHC were also assessed and compared with VP. RESULTS: VP values were inversely related to mPAP (r -0.427, p 0.003), DPG (r -0.36, p 0.019), TPG (r: -0.43, p 0.004), and PVR (r -0.52, p 0.001). Correlations remained significant even after correction at multivariate analysis for age and gender. VP values below median identified subjects with mPAP ≥ 25 mmHg with an odds ratio of 4.5 (95% confidence interval 1.05-19.36, p < 0.05), an accuracy of 0.712 at ROC curve analysis (95% confidence interval 0.534-0.852, p < 0.05) and a positive predictive power 82%. CONCLUSIONS: In patients with suspected PAH, VP assessed at CPET might provide further information in predicting PAH at RHC. Correlations with PVR and DPG may be helpful in differentiating patients with isolated post-capillary PH from those with combined post-capillary and pre-capillary.

The additive value of echocardiographic pulmonary to left atrial global strain ratio in the diagnosis of pulmonary hypertension.

BACKGROUND: The distinction between pre-capillary and post-capillary pulmonary hypertension (PH) is central to accurate diagnosis and appropriate therapy. We aimed to investigate the ability of the novel echocardiographic pulmonary to left atrial global strain ratio (ePLAGS) to distinguish pre-capillary from post-capillary PH and compare its discriminatory strength with the echocardiographic pulmonary to left atrial ratio (ePLAR). METHODS: Consecutive subjects with unexplained dyspnea or heart failure underwent echocardiography immediately followed by right heart catheterization. Subjects who did not satisfy the ESC/ERS criteria for PH, in atrial fibrillation or under pacemaker therapy, or with significant concomitant valvular disease were excluded. ePLAGS was calculated as peak tricuspid regurgitation velocity divided by left atrial global reservoir strain. RESULTS: One hundred and thirty PH subjects, as defined by right heart catheterization, were included in the analysis (pre-capillary: n = 64, post-capillary: n = 66). ePLAGS was lower in pre-capillary compared with post-capillary PH (0.19 ±â€¯0.14 vs. 0.45 ±â€¯0.58 m/s/%; p = 0.02) and significantly different between combined post- and pre-capillary PH (Cpc-PH) and isolated post-capillary PH (Ipc-PH) (0.62 ±â€¯0.85 vs. 0.32 ±â€¯0.19 m/s/%; p = 0.04). ePLAR was higher in pre-capillary as compared with post-capillary PH (0.37 ±â€¯0.16 vs. 0.20 ±â€¯0.08; p < 0.001) but did not differ between Ipc-PH and Cpc-PH. ePLAGS demonstrated stronger discriminating power than ePLAR to distinguish pre-capillary from post-capillary PH (AUC = 0.80 vs. 0.70). In the setting of post capillary PH, ePLAGS showed reasonable ability to distinguish Ipc-PH from Cpc-PH (AUC = 0.65). ePLAR, however, did not differentiate these two groups (AUC = 0.49; p > 0.05). CONCLUSIONS: ePLAGS accurately differentiates pre-capillary from post-capillary PH and demonstrates higher diagnostic ability than ePLAR.

Evaluation of the right ventricle by echocardiography: particularities and major challenges.

INTRODUCTION: Compared with the left ventricle (LV), the right ventricle (RV) is less suited for evaluation by echocardiography (ECHO). Nevertheless, RV ECHO-assessment has currently emerged as an important diagnostic tool with meaningful prognostic value and essential contribution to therapeutic decisions. Although significant progress has been made, including generation of higher-quality normative data, validation of several two-dimensional measurements and improvements in three-dimensional ECHO-techniques, many challenges in RV ECHO-assessment still persist. Areas covered: This review discusses the particular challenges and limits in obtaining accurate measurements of RV anatomical and functional parameters and focuses primarily on the difficulties in proper interpretation of the highly load dependent RV ECHO-parameters which complicates the use of this valuable diagnostic and surveillance technique. Expert commentary: There is increasing evidence that RV assessment in relation with its actual loading conditions by ECHO-derived composite variables, which either incorporate a certain functional parameter and load, or incorporate measures which reflect the relationship between RV dilation and RV load, considering also the right atrial pressure (i.e. 'load adaptation index'), is particularly suited for clinical decision-making. Load dependency of RV ECHO-parameters must be taken into consideration especially in patients with advanced RV dysfunction scheduled for LV assist device implantation or lung transplantation.

Chronic thromboembolic pulmonary hypertension: Reversal of pulmonary hypertension but not sleep disordered breathing following pulmonary endarterectomy.

BACKGROUND: It has been hypothesized that pre-capillary pulmonary hypertension (PH) may trigger sleep disordered breathing (SDB). In patients with chronic thromboembolic PH (CTEPH), pulmonary endarterectomy (PEA) is potentially effective to improve PH. We assessed the pre- and post-operative prevalence of SDB in CTEPH patients submitted to PEA and the relationship between SDB and clinical, pulmonary and hemodynamic factors. METHODS: Unattended cardiorespiratory recording was performed the night before and one month after elective PEA in 50 patients. RESULTS: Before the intervention SDB prevalence (obstructive or central AHI ≥ 5/h) was 64%: 18 patients (66% female) had No-SDB, 22 (68% female) had dominant obstructive (dOSA), and 10 (20% female) had dominant central sleep apnea (dCSA). There were no differences in risk factors and the need for supplemental oxygen. Mean right atrial (mRAP) and pulmonary artery pressures (mPAP) showed a more compromised profile from No-SDB to dOSA and dCSA (mRAP: 5.5 ±â€¯3.9 vs 7.0 ±â€¯4.5 vs 9.7 ±â€¯4.3 mm Hg (p = 0.054), mPAP: 39 ±â€¯12 vs 48 ±â€¯11 vs 51 ±â€¯16 mm Hg (p = 0.0.47)). By contrast, cardiac index did not differ. At post-intervention, the prevalence of SDB was 68%: 16 patients had No-SDB, while 30 had dOSA and 4 dCSA, with no relationship with the relief from PH. Interestingly, 5 patients with previous CSA moved to the OSA group and 2 normalized. CONCLUSIONS: Prevalence of SDB is high in patients with CTEPH even after resolution of PH. Our data support the hypothesis that pre-capillary PH may trigger CSA but not OSA, and suggest that OSA may play a role in the development of CTEPH.