Pulmonary artery pressure variation in patients with connective tissue disease: 24 hour ambulatory pulmonary artery pressure monitoring

Twelve-month follow-up results from the SIRONA 2 clinical trial

AIMS

In the SIRONA 2 trial, the safety and efficacy of pulmonary artery (PA) pressure (PAP)-guided heart failure (HF) management using a novel PAP sensor were assessed at 30 and 90 days, respectively, and both endpoints were met. The current study examines the prespecified secondary endpoints of safety and accuracy of the PA sensor along with HF hospitalizations and mortality, HF symptoms, functional capacity, quality of life, and patient compliance through 12 months.

METHODS AND RESULTS

SIRONA 2 is a prospective, multi-centre, open-label, single-arm trial evaluating the Cordella™ PA Sensor System in 70 patients with New York Heart Association (NYHA) functional class III HF with a prior HF hospitalization and/or increase of N-terminal pro-brain natriuretic peptide within 12 months of enrolment. Sensor accuracy was assessed and compared with measurements obtained by standard right heart catheterization (RHC). Safety was defined as freedom from prespecified adverse events associated with use of the Cordella PA Sensor System and was assessed in all patients who entered the cath lab for PA sensor implant. HF hospitalizations and mortality, HF symptoms, functional capacity, quality of life, and patient compliance were also assessed. At 12 months, there was good agreement between the Cordella PA Sensor System and RHC, with the average difference for mean PAP being 2.9 ± 7.3 mmHg. The device safety profile was excellent with 98.4% freedom from device/system-related complications. There were no pressure sensor failures. HF hospitalizations and mortality were low with a rate of 0.33 event per patient year. Symptoms as assessed by NYHA (P < 0.0001) and functional capacity as measured by 6 min walk test (P = 0.02) were significantly improved. Patients' adherence to daily transmissions of PAP and vital signs measurements was 95%.

CONCLUSIONS

Long-term follow-up of the SIRONA 2 trial supports the safety and accuracy of the Cordella PA Sensor System in enabling comprehensive HF management in NYHA class III HF patients.

Orthostatic variation of pulmonary artery pressure in ambulatory heart failure patients

AIM

To study effect of change in position (supine and standing) on pulmonary artery pressure (PAP) in ambulatory heart failure (HF) patients.

METHODS

Seventeen patients with CardioMEMS® sensor and stable heart failure were consented and included in this single center study. Supine and standing measurements were obtained with at least 5 min interval between the two positions. These measurements included PAP readings utilizing the manufacturer handheld interrogator obtaining 10 s data in addition to the systemic blood pressure and heart rate recordings.

RESULTS

Mean supine and standing readings and their difference (Δ) were as follows respectively: Systolic PAP were 33.4 (± 11.19), 23.6 (± 10) and Δ was 9.9 mmHg (p = 0.0001), diastolic PAP were 14.2 (± 5.6), 7.9 (± 5.7) and Δ was 6.3 mmHg (p = 0.0001) and mean PAP were 21.8 (± 7.8), 14 (± 7.2) and Δ was 7.4 mmHg (p = 0.0001) while the systemic blood pressure did not vary significantly.

CONCLUSION

There is orthostatic variation of PAP in ambulatory HF patients demonstrating a mean decline with standing in diastolic PAP by 6.3 mmHg, systolic PAP by 9.9 mmHg and mean PAP by 7.4 mmHg in absence of significant orthostatic variation in systemic blood pressure or heart rate. These findings have significant clinical implications and inform that PAP in each patient should always be measured in the same position. Since initial readings at the time of implant were taken in supine position, it may be best to use supine position or to obtain a baseline standing PAP reading if standing PAP is planned on being used.

Rationale and Design of the Proactive-HF Trial for Managing Patients With NYHA Class III Heart Failure by Using the Combined Cordella Pulmonary Artery Sensor and the Cordella Heart Failure System

BACKGROUND

Optimizing guideline-directed medical therapy (GDMT) and monitoring congestion in patients with heart failure (HF) are key to disease management and preventing hospitalizations. A pulmonary artery pressure (PAP)-guided HF management system providing access to body weight, blood pressure, heart rate, blood oxygen saturation, PAP, and symptoms, may provide new insights into the effects of patient engagement and comprehensive care for remote GDMT titration and congestion management.

METHODS

The PROACTIVE-HF study was originally approved in 2018 as a prospective, randomized, controlled, single-blind, multicenter trial to evaluate the safety and effectiveness of the Cordella PAP Sensor in patients with HF and with New York Heart Association (NYHA) functional class III symptoms. Since then, robust clinical evidence supporting PAP-guided HF management has emerged, making clinical equipoise and enrolling patients into a standard-of-care control arm challenging. Therefore, PROACTIVE-HF was changed to a single-arm trial in 2021 with prespecified safety and effectiveness endpoints to provide evidence for a similar risk/benefit profile as the CardioMEMS HF System.

CONCLUSION

The single-arm PROACTIVE-HF trial is expected to further demonstrate the benefits of PAP-guided HF management of patients with NYHA class III HF. The addition of vital signs, patient engagement and self-reported symptoms may provide new insights into remote GDMT titration and congestion management.

[Diagnostic Application of Invasive Cardiopulmonary Exercise Test in Patients with Unexplained Dyspnea]

OBJECTIVE

To explore the clinical diagnostic application of invasive cardiopulmonary exercise test (iCPET) in patients with unexplained dyspnea.

METHODS

A retrospective analysis was conducted, covering patients with a chief complaint of exertional dyspnea between May 5, 2017 and October 1, 2020. Right cardiac catheterization examination was performed on patients whose cause had not been identified through routine examination, and further iCPET was performed on patients if no clear etiology was identified through right cardiac catheterization. According to the results and the diagnostic criteria of iCPET, patients showing no obvious abnormalities in the right cardiac catheterization examination were divided into four subgroups: exercise-induced pulmonary arterial hypertension (eiPAH), exercise-induced heart failure with preserved ejection fraction (eiHFpEF), preload failure, and oxidative myopathy. By comparing the lab test, echocardiography, right heart catheter and iCPET peak exercise data of the subgroups, the disease distribution and exercise hemodynamic characteristics of patients with unexplained dyspnea examined by iCPET were described.

RESULTS

Of the 1 046 patients with exertional dyspnea, 771 were diagnosed with routine examination, while among the remaining 275 patients, 131 (47.6%) were diagnosed with right cardiac catheterization and 144 (52.4%) showed no clear etiology after routine examination and right cardiac catheterization. Of these 144 patients, 49 (34.0%) received iCPET with a median exercise time of 375 s. A total of 47 patients completed the examination, with a male-to-female ratio of 0.27∶1 and an average age of (47.9±14.4) years old. Among the 47 patients, 76.6% (36/47) aged between 20 and 59 and 78.7% (36/47) lived in urban areas. The preload failure group ( n=27) showed low right atrium pressure at peak exercise intensity. The eiHFpEF group ( n=9) showed high wedge pressure of pulmonary capillaries at peak of exercise intensity. The eiPAH group ( n=8) showed high average pulmonary artery pressure at peak exercise intensity. The oxidative myopathy group ( n=3) was characterized by impairment of tissue uptake and/or utilization of oxygen during exercise. According to the comparison among the three subgroups of the preload failure, eiHFpEF and eiPAH, the eiPAH group had the highest blood K + level in routine examination, while the preload failure group had the lowest blood K + level ( P=0.014). The iCPET of the three subgroups showed statistically significant ( P=0.001) difference in right atrial pressure increase during exercise. Among the three, the eiHFpEF group had the highest increase and the preload failure group had the lowest increase. Conclusion 　In unexplained dyspnea patients showing no abnormal results in right cardiac catheterization examination, the main cause was preload failure, which manifested as low right atrial pressure at peak exercise intensity. The study showed that iCPET was of important value for dyspnea cases when the cause of the condition was not revealed with right cardiac catheterization.

A review of exercise pulmonary hypertension in systemic sclerosis

In general, pulmonary vascular disease has important negative prognostic implications, regardless of the associated condition or underlying mechanism. In this regard, systemic sclerosis is of particular interest as it is the most common connective tissue disease associated with pulmonary hypertension, and a well-recognized at-risk population. In the setting of systemic sclerosis and unexplained dyspnea, the concept of using exercise to probe for underlying pulmonary vascular disease has acquired significant interest. In theory, a diagnosis of systemic sclerosis-associated exercise pulmonary hypertension may allow for earlier therapeutic intervention and a favorable alteration in the natural history of the pulmonary vascular disease. In the context of underlying systemic sclerosis, the purpose of this article is to provide a comprehensive review of the evolving definition of exercise pulmonary hypertension, the current role and methodologies for non-invasive and invasive exercise testing, and the importance of the right ventricle.

Complementary role of cardiovascular imaging and laboratory indices in early detection of cardiovascular disease in systemic lupus erythematosus

Background

Cardiovascular disease (CVD) has been documented in >50% of systemic lupus erythematosus (SLE) patients, due to a complex interplay between traditional risk factors and SLE-related factors. Various processes, such as coronary artery disease, myocarditis, dilated cardiomyopathy, vasculitis, valvular heart disease, pulmonary hypertension and heart failure, account for CVD complications in SLE.

Methods

Electrocardiogram (ECG), echocardiography (echo), nuclear techniques, cardiac computed tomography (CT), cardiovascular magnetic resonance (CMR) and cardiac catheterization (CCa) can detect CVD in SLE at an early stage. ECG and echo are the cornerstones of CVD evaluation in SLE. The routine use of cardiac CT and nuclear techniques is limited by radiation exposure and use of iodinated contrast agents. Additionally, nuclear techniques are also limited by low spatial resolution that does not allow detection of sub-endocardial and sub-epicardial lesions. CCa gives definitive information about coronary artery anatomy and pulmonary artery pressure and offers the possibility of interventional therapy. However, it carries the risk of invasive instrumentation. Recently, CMR was proved of great value in the evaluation of cardiac function and the detection of myocardial inflammation, stress-rest perfusion defects and fibrosis.

Results

An algorithm for CVD evaluation in SLE includes clinical, laboratory, ECG and echo assessment as well as CMR evaluation in patients with inconclusive findings, persistent cardiac symptoms despite normal standard evaluation, new onset of life-threatening arrhythmia/heart failure and/or as a tool to select SLE patients for CCa.

Conclusions

A non-invasive approach including clinical, laboratory and imaging evaluation is key for early CVD detection in SLE.

Right ventricular thickness as predictor of global myocardial performance in systemic sclerosis: A Doppler tissue imaging study

BACKGROUND

Cardiopulmonary involvement in systemic sclerosis (SSc) is a poor prognostic factor, due to pulmonary hypertension and right ventricular dysfunction. We assessed the echocardiographic parameters of right ventricular (RV) function in SSc and correlated echocardiographic findings to clinical features of the disease.

METHODS

Thirty patients with SSc (cases) and 30 healthy, age-matched subjects (controls) were studied. Echocardiography, including tissue Doppler imaging, was used to evaluate cardiac function.

RESULTS

Pulmonary hypertension could be documented in only 5 cases by Doppler echo, using Bernoulli principle. RV diastolic function was significantly deranged in cases. RV systolic function and left ventricle (LV) diastolic function were also significantly deranged in the cases. RV thickness was increased in patients with SSc. There were no significant differences in the echocardiographic variables between diffuse and limited subtypes of SSc. Myocardial performance index (MPI) of both ventricles were increased in cases. We could demonstrate RV thickness as the single most important predictor of MPI of both ventricles with sensitivity of 82% and specificity of 72% for RV-MPI and 63% for LV-MPI. Diastolic function was not found to be affected by disease duration or Rodnan skin score.

CONCLUSION

Patients with SSc exhibit abnormal RV and LV diastolic functions as well as abnormal RV systolic function. RV wall thickness was found to be simple and the single best predictor of global myocardial performance. RV dysfunction may be a response to intermittent pulmonary arterial hypertension, lung parenchymal involvement, or secondary to LV diastolic dysfunction in SSc.

Endpoints in PAH clinical trials in the era of combination therapy: how do we decide whether something is working without going bankrupt?

There has been substantial progress in the treatment of pulmonary arterial hypertension using specific disease-targeted therapies. As the number of agents available grows, and as new treatment strategies emerge, it is essential that the endpoints we use to assess efficacy are sufficiently meaningful and sensitive enough to detect changes that are often subtle. Although the six-minute walk has been the traditional primary endpoint in clinical trials, there is now a move towards more patient-centred composite endpoints such as time to clinical worsening. These endpoints need to be more clearly defined and universally applied so as to make direct comparison between new drugs and new combinations possible.

[Targeted therapies in severe asthma: the discovery of new molecules]

The pathophysiological mechanisms involved in the chronicity and phenotypic heterogeneity of asthma offer the prospect of new therapeutic opportunities. A better clinical and biological characterisation of selected patients has led to the development of targeted therapies. Studies are under way to demonstrate their efficacy and tolerance and also their impact on the natural history of the disease. This revue aims to examine the therapies, developed during the last ten years, that are based on the immunological mechanisms involved in the pathophysiology of asthma, essentially in its severe form. The rapid expansion of human monoclonal antibodies has allowed testing of various immunological pathways. Anti-IgE, anti- IL-5, and anti-IL-13 strategies seem the most promising. Antagonists to TNF-alpha and I'IL-4 have not succeeded in reducing the events related to severe asthma in a convincing manner. Molecules targeted against thymic stromal lymphopoietin (TSLP) and I'IL-9 are under development. These approaches are involved in the development of therapeutic programmes adapted to the patient's phenotype, that is to say a personalised approach to care.

Detection of exercise-induced pulmonary arterial hypertension by cardiopulmonary exercise testing

BACKGROUND

The pulmonary arterial pressure (PAP) response to exercise may provide a tool for the early detection of pulmonary arterial hypertension (PAH). Therefore, an accurate noninvasive method for evaluating exercise-induced PAH (EIPAH) is desirable.

HYPOTHESIS

We sought to examine if cardiopulmonary exercise testing (CPET) is able to indicate EIPAH.

METHODS

Fifty-three patients aged 67.1 ± 1.7 years (37 female, 16 male) with borderline PAH (resting mean PAP 21-24 mm Hg) performed CPET and right heart catheterization at rest and during handgrip testing.

RESULTS

When comparing patients with an exercise-induced mean PAP ≥ mm Hg (group A, n = 24) and subjects with an exercise-induced mean PAP <35 mm Hg (group B, n = 29), group A had a significantly lower mean aerobic capacity (15.2 ± 1.2 vs 19.7 ± 1.2 mL/min/kg; P = 0.02), higher ventilatory equivalents for oxygen at the anaerobic threshold (34.3 ± 1.5 vs 29.9 ± 1.1; P = 0.02), a widening of the mean alveolar-arterial oxygen difference (37.8 ± 3.0 vs 26.8 ± 2.4 mm Hg; P = 0.007), an elevated mean functional dead space ventilation (29.5 ± 2.7 vs 21.2 ± 1.7%; P = 0.008), and a higher mean arterial to end-tidal carbon dioxide gradient at peak exercise (3.7 ± 0.9 vs 0.4 ± 0.8 mm Hg; P = 0.007).

CONCLUSIONS

EIPAH is characterized by a decreased ventilatory efficiency due to ventilation to perfusion inequalities. CPET may be useful for the identification of EIPAH and serve to diagnose PAH at an early stage.

Cardiopulmonary exercise testing in the assessment of pulmonary hypertension

The assessment of patients with suspected or confirmed pulmonary arterial hypertension (PAH) and secondary pulmonary hypertension (PH) continues to evolve and, in recent years, evidence demonstrating that cardiopulmonary exercise testing (CPX) provides valuable information has grown at an impressive rate. The key premise supporting the use of CPX is that certain variables obtained provide insight into the degree of ventilation/perfusion mismatching secondary to altered pulmonary hemodynamics. In this article, we discuss the pathophysiology of PAH and secondary PH and its impact on cardiac function, review the clinical presentation of patients with elevated pulmonary pressures and outline a case for the use of CPX as an integral assessment technique, discuss CPX technology and testing procedures, and review the current state of available evidence and provide clinical recommendations for CPX in the setting of known or suspected PAH and secondary PH.

Prediction of pulmonary hypertension in patients with or without interstitial lung disease: reliability of CT findings

PURPOSE

To study the reliability of pulmonary vascular measurements based on computed tomography (CT) in the prediction of pulmonary hypertension (PH) in patients with advanced interstitial lung disease (ILD) compared with those without ILD.

MATERIALS AND METHODS

The study was approved by the Institutional Review Board. All patients gave written informed consent. A prospective study of 134 patients who underwent right-sided heart catheterization and chest CT scanning within 72 hours of admission was conducted. Patients were divided into two groups-one with ILD (group A, n = 100) and one without ILD (group B, n = 34). CT measurements of the main pulmonary artery diameter (PAD), the ratio of PAD to the ascending aorta diameter (AAD), right pulmonary artery diameter (RPAD), and left pulmonary artery diameter (LPAD) were obtained. Univariate logistic regression analysis was performed, and receiver operating characteristic curves were constructed to assess the predictive ability of vascular measurements obtained by using CT in the identification of PH.

RESULTS

Main PAD was significantly greater in patients with PH than in those without PH in both groups (group A, P = .008; group B, P = .02). A PAD greater than 25 mm in patients with ILD was predictive of PH, with a sensitivity of 86.4% (32 of 37), a specificity of 41.2% (26 of 63), a positive predictive value of 46.3% (32 of 69), and a negative predictive value of 83.8% (26 of 31). In patients without ILD, a PAD greater than 31.6 mm and an LPAD greater than 21.4 mm were predictive of PH (sensitivity, 47.3% [nine of 19]; specificity, 93.3% [14 of 15]; positive predictive value, 90.0% [nine of 10]; and negative predictive value, 58.3% [14 of 24]).

CONCLUSION

CT-derived vascular measurements were of limited utility in the prediction of PH in patients with ILD compared with those without ILD.

Pulmonary Vascular Response Patterns to Exercise: Is there a Role for Pulmonary Arterial Pressure Assessment during Exercise in the Post-Dana Point Era?

Pulmonary hypertension (PH) is often diagnosed late in its course when it purports a particularly poor prognosis. Exercise effectively unmasks early forms of several cardiopulmonary diseases but the role of performing pulmonary arterial pressure measurements during exercise in the evaluation of PH remains unclear. Whether pulmonary arterial pressure-flow relationships during exercise may provide a window into earlier diagnosis of functionally significant pulmonary arterial hypertension and left ventricular dysfunction,¹ or add incrementally to our armentarium of diagnostic tests and prognostic indicators in PH, is the topic of active ongoing investigation. Evidence is emerging that abnormal pulmonary arterial pressure response patterns to exercise, when properly indexed to increased blood flow, may help to identify early forms of heart failure and pulmonary arterial hypertension. This article will discuss approaches to performing hemodynamic measurements during exercise as well as the potential clinical utility of identifying normal and abnormal pulmonary vascular response patterns to exercise.

Early right ventricular systolic dysfunction in patients with systemic sclerosis without pulmonary hypertension: a Doppler Tissue and Speckle Tracking echocardiography study

Background

Isovolumetric acceleration (IVA) is a novel tissue Doppler parameter for the assessment of systolic function. The aim of this study was to evaluate IVA as an early parameter for the detection of right ventricular (RV) systolic dysfunction in patients with systemic sclerosis (SSc) without pulmonary hypertension.

Methods

22 patients and 22 gender- and age-matched healthy subjects underwent standard echocardiography with tissue Doppler imaging (TDI) and speckle tracking strain to assess RV function.

Results

Tricuspid annular plane systolic excursion (TAPSE) (23.2 ± 4.1 mm vs. 26.5 ± 2.9 mm, p < 0.006), peak myocardial systolic velocity (Sm) (11.6 ± 2.3 cm/s vs. 13.9 ± 2.7 cm/s, p = 0.005), isovolumetric contraction velocity (IVV) (10.3 ± 3 cm/s vs. 14.8 ± 3 cm/s, p < 0.001) and IVA (2.3 ± 0.4 m/s² vs. 4.1 ± 0.8 m/s², p < 0.001) were significant lower in the patient group. IVA was the best parameter to predict early systolic dysfunction with an area under the curve of 0.988.

Conclusion

IVA is a useful tool with high-predictive power to detect early right ventricular systolic impairment in patients with SSc and without pulmonary hypertension.

Receptor-Mediated Basic Fibroblast Growth Factor Signaling Regulates Cyclic Pressure–Induced Human Endothelial Cell Proliferation

Vascular endothelial cells sense and respond to pressure by molecular mechanism(s) which, to date, remain poorly understood. The present study investigated basic fibroblast growth factor (bFGF) signaling as a putative mechanotransduction pathway involved in the proliferative responses of human umbilical vein endothelia cells (HUVECs) to 60/20 mm Hg cyclic pressure at 1 Hz for 24 h. Under these conditions, the enhanced proliferative response of these HUVECs was not associated with an increased synthesis/release of bFGF, but involved rapid (within 30 min from the onset of exposure to pressure) tyrosine phosphorylation of the bFGF receptor, FGFR-2. Furthermore, monoclonal antibodies to either bFGF or FGFR-2 attenuated the increased proliferation of HUVECs exposed to 60/20 mm Hg cyclic pressure. HUVECs proliferation under 60/20 mm Hg at 1 Hz cyclic pressure is, therefore, dependent upon bFGF and involves FGFR-2 activation.

Exercise-induced pulmonary arterial hypertension

BACKGROUND

The clinical relevance of exercise-induced pulmonary arterial hypertension (PAH) is uncertain, and its existence has never been well studied by direct measurements of central hemodynamics. Using invasive cardiopulmonary exercise testing, we hypothesized that exercise-induced PAH represents a symptomatic stage of PAH, physiologically intermediate between resting pulmonary arterial hypertension and normal.

METHODS AND RESULTS

A total of 406 consecutive clinically indicated cardiopulmonary exercise tests with radial and pulmonary arterial catheters and radionuclide ventriculographic scanning were analyzed. The invasive hemodynamic phenotype of exercise-induced PAH (n=78) was compared with resting PAH (n=15) and normals (n=16). Log-log plots of mean pulmonary artery pressure versus oxygen uptake (V(.)o(2)) were obtained, and a "join-point" for a least residual sum of squares for 2 straight-line segments (slopes m1, m2) was determined; m2<m1="plateau," and m2>m1="takeoff" pattern. At maximum exercise, V(.)o(2) (55.8+/-20.3% versus 66.5+/-16.3% versus 91.7+/-13.7% predicted) was lowest in resting PAH, intermediate in exercise-induced PAH, and highest in normals, whereas mean pulmonary artery pressure (48.4+/-11.1 versus 36.6+/-5.7 versus 27.4+3.7 mm Hg) and pulmonary vascular resistance (294+/-158 versus 161+/-60 versus 62+/-20 dyne x s x cm(-5), respectively; P<0.05) followed an opposite pattern. An exercise-induced PAH plateau (n=32) was associated with lower o(2)max (60.6+/-15.1% versus 72.0+/-16.1% predicted) and maximum cardiac output (78.2+/-17.1% versus 87.8+/-18.3% predicted) and a higher resting pulmonary vascular resistance (247+/-101 versus 199+/-56 dyne x s x cm(-5); P<0.05) than takeoff (n=40). The plateau pattern was most common in resting PAH, and the takeoff pattern was present in nearly all normals.

CONCLUSIONS

Exercise-induced PAH is an early, mild, and clinically relevant phase of the PAH spectrum.

The relationship between the components of pulmonary artery pressure remains constant under all conditions in both health and disease

BACKGROUND

The relationships among systolic pulmonary artery pressure (SPAP), diastolic pulmonary artery pressure (DPAP), and mean pulmonary artery pressure (MPAP) have been found to be constant in humans breathing air, at rest, while supine. It would be important for those studying the pulmonary circulation if this relationship were maintained under other circumstances, such as change in posture, during exercise, or after pharmacologic manipulation. In particular, it would be useful if the relationship were maintained when treating pulmonary hypertension because this would allow different methods of measurement to be compared, such as SPAP from echocardiography and MPAP from right heart catheterization.

METHODS

Data were reviewed from both healthy subjects and those with pulmonary hypertension (n = 65) who had a micromanometer-tipped, high-fidelity pulmonary artery catheter inserted for between 6 and 36 h in the Scottish Pulmonary Vascular Unit between 1997 and 2003. The 5-min averages, while the patient was supine at rest, were analyzed by linear regression to compare the response of SPAP and DPAP with MPAP.

RESULTS

There were linear relationships (measured in millimeters of mercury) of SPAP with MPAP (SPAP = 1.50 MPAP + 0.46), and DPAP with MPAP (DPAP = 0.71 MPAP - 0.66). These were maintained with a high degree of accuracy following changes in posture and activity.

CONCLUSIONS

SPAP, MPAP, and DPAP were strongly related, and these relationships were maintained under varying conditions. This finding will allow comparison between invasive and noninvasive descriptions of pulmonary hemodynamics found in the literature.

Exercise Doppler echocardiography identifies preclinic asymptomatic pulmonary hypertension in systemic sclerosis

In systemic sclerosis (SSc), the involvement of the interstitium or vascular system of the lung may lead to pulmonary arterial hypertension (PAH). PAH is often asymptomatic or oligosymptomatic in early SSc and, when it becomes symptomatic, pulmonary vascular system is already damaged. Exercise echocardiography (ex-echo), measuring pulmonary artery pressure (PAP) during exercise and allowing to differentiate physiologic from altered PAP responses, may identify subclinical PAH. Our aims were (a) to evaluate by ex-echo the change of PAP in patients with SSc without lung involvement; and (b) to correlate PAP during exercise (ex-PAP) values to clinical and biohumoral parameters of PAH. Twenty-seven patients with limited SSc (ISSc) without interstitial lung involvement were studied. Patients underwent rest and exercise two-dimensional and Doppler echocardiography by supine cycloergometer. Systolic PAP was calculated using the maximum systolic velocity of the tricuspid regurgitant jet at rest and during exercise values of systolic PAP exceeding 40 mmHg at ex-echo were considered as abnormal, and biohumoral markers potentially related to PAH were assessed. Eighteen of 27 SSc patients presented an ex-PAP > 40 mmHg, while in 9 of 27 patients ex-PAP values remained < 40 mmHg (48.8 +/- 4.5 mmHg versus 36.2 +/- 3.1 mmHg; P < 0.001). Other echocardiographic and ergometric parameters, clinical tests, and biohumoral markers were not different in the two groups. Ex-PAP significantly correlated with D-dimer (P = 0.0125; r2 = 0.2029). Ex-echo identifies a cluster of SSc patients with subclinical PAH that may develop PAH. This group should be followed up and may be considered for specific therapies to prevent disease evolution.

Diagnosis of pulmonary arterial hypertension

Accurate diagnosis of pulmonary arterial hypertension is a challenging and complex process that requires a high index of clinical suspicion from even the most astute clinician. This article discusses the use of a variety of noninvasive tests that can help define the population of patients in whom invasive cardiac catheterization should be pursued. It points out the vagaries and limitations of electrocardiography and the radiographic and echocardiographic clues to the diagnosis. Ultimately, right- and, often, concomitant left-heart catheterization is required to establish the diagnosis and distinguish pulmonary arterial hypertension from pulmonary venous hypertension.

Echocardiography versus right-sided heart catheterization among lung transplantation candidates

BACKGROUND

Right-heart-catheterization and transthoracic echocardiography are routine tests to measure pulmonary artery systolic pressure among lung transplantation candidates. Echocardiography may be as accurate as right-heart-catheterization, without the inherent risks of an invasive test.

METHODS

We examined the correlation between pulmonary pressures estimated by echocardiography versus right-heart-catheterization among lung transplantation candidates and their correlation to measurements during lung transplantation. Our cohort included all lung transplantation candidates during 1997 through 2004 who initially underwent pulmonary pressure evaluation by right-heart-catheterization and echocardiography, as well as measurements during lung transplantation.

RESULTS

Of the 106 candidates, evaluation by transthoracic echocardiography was possible in 79 (74.5%). Median pulmonary systolic pressures by right-heart-catheterization was 44.0 [33.2-50.0] mm Hg and by echocardiography 40.0 [32.5-51.5] mm Hg (r = 0.80, p < 0.0001). In 14 (17.7%) patients the difference between the 2 methods was > 20 mm Hg. The median time interval between echocardiography and right-heart-catheterization was 65 [40-155] days. The median value of pulmonary systolic pressure measured during lung transplantation in 44 (70.1%) of 62 patients was 39.5 [31.0-50.0] mm Hg. The time interval right-heart-catheterization-to-lung transplantation was 143 [87-339] days and echocardiography-to-lung transplantation 229 [130-367] days. The correlation between measurements during lung transplantation and initial measurements by right-heart-catheterization and echocardiography were r = 0.50 and r = 0.31, respectively, with corresponding p values of p = 0.001 and p = 0.07.

CONCLUSIONS

For lung transplantation candidates and a suitable transthoracic echocardiography estimate of pulmonary systolic pressure, the need for right-heart catheterization, with its inherent risks for complications, may be foregone. The weak correlation between the initial and intraoperative measurements, probably stemming from the significant time interval, suggests that serial measurements may be needed.

Incidence of Pulmonary Hypertension and Its Clinical Relevance in Patients With Sarcoidosis

OBJECTIVE

To investigate the frequency of pulmonary hypertension (PH) and clinical parameters associated with PH in sarcoidosis patients.

METHODS

A prospective, observational study was performed on 246 consecutive Japanese sarcoidosis patients followed up at the outpatient sarcoidosis clinic in the Central Clinic of Kyoto. The patients were evaluated for PH by Doppler echocardiography. Among these patients, 192 underwent pulmonary function tests. In addition, high-resolution CT of the lung was evaluated for the presence of lymph node enlargement, lung opacity, and thickening of bronchovascular bundles in 122 patients. PH was defined as estimated systolic pulmonary artery pressure (sPAP) > or = 40 mm Hg. The frequency of PH was evaluated, and clinical parameters were compared between patients with PH and those without PH.

RESULTS

Among 212 patients who were successfully evaluated for sPAP, 12 patients (5.7%) had PH. Patients with PH had the following clinical characteristics: advanced chest radiographic stage, decreased oxygen saturation, predominantly male gender, and decreased percentage of predicted vital capacity, percentage of predicted FVC, percentage of predicted FEV1, percentage of predicted functional residual capacity, and percentage of predicted total lung capacity (%TLC). Multivariate logistic regression analysis showed that decreased %TLC was independently associated with PH. There was a weak negative correlation between sPAP and %TLC (p < 0.05).

CONCLUSIONS

The frequency of PH in Japanese sarcoidosis patients was 5.7% evaluated with Doppler echocardiography. Decreased lung volume increases the risk of PH developing in patients with sarcoidosis.

Right ventricular myocardial isovolumic relaxation time and pulmonary pressure. Pulsed Doppler tissue imaging in resurrection of Burstin's nomogram

AIMS

Non-invasive assessment of pulmonary artery systolic pressure (PASP) has several limitations. As previously described by Burstin, the right ventricular (RV) isovolumic relaxation time (IVRt) is sensitive to changes in PASP. We therefore compared RV myocardial IVRt, derived by Doppler tissue imaging (DTI), with simultaneously measured invasive PASP.

METHODS AND RESULTS

Twenty-six consecutive patients (18 males, mean age 52 +/- 12 years, range 23-75) underwent a simultaneous Doppler echocardiography, including DTI, and cardiac catheterization examination for measurement of PASP and right atrial mean pressures. IVRt was measured using the myocardial velocities by pulsed DTI at both basal and mid cavity segments of the RV free wall. As diastolic time intervals are influenced by heart rate IVRt was corrected for heart rate (IVRt/RR%). A significant correlation was found between PASP and regional IVRt/RR% at both the basal (r = 0.42, P<0.05) and mid cavity segment (r = 0.71, P<0.001). Furthermore, when only patients with normal right atrial pressures (<7 mmHg) were taken into account, the correlation coefficient improved at both basal and mid cavity segments (r = 0.74, P<0.05 and r = 0.83, P<0.01).

CONCLUSION

Pulsed Doppler-derived IVRt correlates well with PASP. The use of pulsed DTI for measurement of IVRt is simple, reproducible and easy to obtain. We propose this method as an additional non-invasive tool in the assessment of PASP.

Disturbed Right Ventricular Diastolic Function in Patients With Systemic Sclerosis

BACKGROUND

Cardiopulmonary involvement in patients with systemic sclerosis (SSc) carries a poor prognosis, mainly due to pulmonary hypertension and right-heart failure. To date, right ventricular (RV) involvement has not been studied in detail. We therefore assessed RV function in patients with SSc and related the findings to the clinical features of the disease.

METHOD

Twenty-six consecutive patients (21 women) with SSc (mean age, 56 +/- 15 years [+/- SD]) and 25 healthy, age-matched control subjects (21 women) were studied. Doppler echocardiography including Doppler tissue imaging was used to evaluate cardiac function. Pulmonary function was also studied.

RESULTS

Compared with control subjects, RV free wall thickness (5.8 +/- 1.7 mm vs 3.7 +/- 1.1 mm, p < 0.001) and right atrial (RA) systolic area (15.9 +/- 3.7 cm2 vs 13.0 +/- 2.3 cm2, p < 0.01) were increased in patients with SSc, while the global early diastolic/atrial component velocity ratio was reduced (1.2 +/- 0.4 vs 1.7 +/- 0.6, p < 0.01). The global isovolumic relaxation time (IVRT) [64 +/- 23 ms vs 39 +/- 13 ms, p < 0.001] and regional IVRT (83 +/- 40 ms vs 46 +/- 24 ms, p < 0.001) were prolonged in patients vs control subjects, whereas the RV global filling time was reduced (454 +/- 122 ms vs 548 +/- 104 ms, p < 0.01). RV systolic function and pulmonary pressures at rest were similar in the two groups, but the pulmonary artery acceleration time was reduced (119 +/- 34 ms vs 141 +/- 29 ms, p < 0.05) in patients compared to control subjects. Left ventricular function did not differ between the two groups.

CONCLUSION

Patients with SSc exhibit altered RV diastolic function together with an increase in RV wall thickness and RA area. These findings appear to be early markers of RV disturbance, probably in response to intermittent pulmonary arterial hypertension.

Screening, early detection, and diagnosis of pulmonary arterial hypertension: ACCP evidence-based clinical practice guidelines

Pulmonary arterial hypertension (PAH) occurs as an idiopathic process or as a component of a variety of disease processes, including chronic thromboembolic disease, connective tissue diseases, congenital heart disease, and exposure to exogenous factors including appetite suppressants or infectious agents such as HIV. This article reviews evidence for screening in susceptible patient groups and the approach to diagnosing PAH when it is suspected, and provides specific recommendations for applying this evidence to clinical practice.

VEGF-C mediates cyclic pressure-induced endothelial cell proliferation

Mechanical forces modulate endothelial cell functions through several mechanisms including regulation of gene transcription. In the present study, gene transcription by human umbilical vein endothelial cells (HUVEC) either maintained under control pressure (that is, standard cell culture conditions equivalent to 0.15 mmHg sustained hydrostatic pressure) or exposed to 60/20 mmHg sinusoidal pressures at 1 Hz were compared using Affymetrix GeneChip microarrays to identify cellular/molecular mechanisms associated with endothelial cell responses to cyclic pressure. Cyclic pressure selectively affected transcription of 14 genes that included a set of mechanosensitive proteins involved in hemostasis (tissue plasminogen activator), cell adhesion (integrin-alpha2), and cell signaling (Rho B, cytosolic phospholipase A2), as well as a unique subset of cyclic pressure-sensitive genes such as vascular endothelial growth factor (VEGF)-C and transforming growth factor (TGF)-beta2. The present study also provided first evidence that VEGF-C, the most highly induced gene under 60/20 mmHg, mediated HUVEC proliferation in response to this cyclic pressure. Cyclic pressure is, therefore, a mechanical force that modulates endothelial cell functions (such as proliferation) by activating a specific transcriptional program.

Ambulatory pulmonary artery pressure monitoring during sleep and exercise in normal individuals and patients with COPD

BACKGROUND

Pulmonary hypertension is a common complication of chronic obstructive airways disease (COPD) and its presence implies a poor prognosis. However, it is difficult to measure and its specific contribution to symptoms is difficult to quantify. A micromanometer tipped pulmonary artery catheter was used to measure pulmonary artery pressure (PAP) during sleep and on exercise.

METHODS

Ten patients (five with COPD receiving long term oxygen therapy and five normal individuals) were studied. Pulmonary artery pressure was recorded continuously during two periods of sleep (breathing oxygen followed by air for the COPD group) and during exercise.

RESULTS

In the COPD group PAP during sleep on oxygen was significantly lower than PAP during sleep breathing air (mean (SD) difference 9.6 (5.3) mm Hg, 95% CI 4.9 to 14.3, p= 0.016). PAP during exercise was not significantly different from PAP during sleep breathing air (mean (SD) difference 0.8 (8.9) mm Hg, 95% CI -7.0 to 8.6, p= 0.851). In normal individuals the group mean (SD) PAP was 15 (5.9) mm Hg for the first nocturnal period and 15 (5.7) mm Hg for the second nocturnal period. PAP during exercise was not significantly different from PAP during sleep breathing air (mean (SD) difference 3.3 (2.2) mm Hg, 95% CI 1.1 to 5.5, p= 0.061).

CONCLUSION

In patients with COPD, PAP rose significantly during sleep to levels similar to those measured during exercise, but this could be reversed with oxygen.

Utility of echocardiography in assessment of pulmonary hypertension secondary to COPD

Studies have confirmed the close correlation of echocardiographically estimated pulmonary arterial pressure with invasive measurements in patients with chronic obstructive pulmonary disease (COPD), but there are few data on utility of echocardiographic measurement in assessing pulmonary arterial hypertension (PH) in COPD and correlation with pulmonary function tests. Presence or absence of tricuspid regurgitation (TR) was determined by Doppler echocardiography in 73 consecutive COPD patients attending a hospital outpatient clinic. Transtricuspid pressure gradient (TTPG) was calculated. PH was defined as TTPG > or =30 mmHg. Patients also underwent spirometry, forced expiratory volume in one second (FEV1), single breath gas transfer (carbon monoxide transfer coefficient; (K(CO)) and carbon monoxide diffusing capacity of the lung; D(L,CO)) and arterial blood gas measurement. Measurable TR was observed in 56/73 patients (77%). There were no differences between the group in which TR was observed compared to that in which it was absent, with regard to age, smoking history nor pulmonary function variables. PH was seen in 31/56 cases (55%), with good reproducibility. There were statistically significant correlations of TTPG with FEV1 (r=-0.26, p=0.05), Kco (r=-0.31, p=0.04) and D(L,CO) (r = -0.42, p = 0.006) expressed as % pred. Stepwise regression analysis showed that age and K(CO) combined provide a multivariate model for prediction of TTPG. It is concluded the presence and degree of pulmonary arterial hypertension is readily and reliably determined by echocardiography in the majority of chronic obstructive pulmonary disease patients. Pulmonary arterial hypertension is common in severe chronic obstructive pulmonary disease and transtricuspid pressure gradient correlates with spirometry and indices of gas transfer, similar to previous invasive studies. In view of the adverse effects of pulmonary arterial hypertension on morbiditv and mortality routine echocardiography in patients with severe chronic obstructive pulmonary disease may be warranted.

Hemodynamic effects of epoprostenol in patients with systemic sclerosis and pulmonary hypertension

STUDY OBJECTIVES

To determine the cause of pulmonary hypertension (PH) in systemic sclerosis (SSc) patients since PH can occur because of pulmonary arteriopathy, pulmonary parenchymal destruction, and left ventricular cardiac dysfunction.

DESIGN AND SETTING

Consecutive case series in a university hospital.

PATIENTS

Nine SSc patients with PH (mean pulmonary artery pressure, 41 mm Hg), with (n = 6) or without (n = 3) concomitant interstitial lung disease (ILD).

METHODS

Acute infusion of epoprostenol was begun at 2 ng/kg/min and was titrated upward at a rate of 2 ng/kg/min every 30 min until symptomatic complications developed or pulmonary artery vascular resistance (PVR) was reduced by 50%.

RESULTS

Eight of nine patients demonstrated a reduction of > or = 20% in PVR, suggesting that vasoreactivity is common despite the presence of significant ILD. A single patient had no response to infusion with unchanged hemodynamics and oxygenation. One patient developed hypoxemia as cardiac output increased, suggesting a worsening of ventilation/perfusion matching or the presence of an anatomic shunt. Acute pulmonary edema developed in one patient at an infusion rate of 6 ng/kg/min. The results of cardiac catheterization suggested that pulmonary edema was caused by SSc heart disease.

CONCLUSION

SSc patients with ILD have diverse and sometimes multiple causes of PH that can be determined by short-term epoprostenol infusion. Beneficial effects can be obtained from epoprostenol despite extensive ILD.