A noninvasive algorithm to exclude pre-capillary pulmonary hypertension

NT-proBNP <95 ng/l can exclude pulmonary hypertension on echocardiography at diagnostic workup in patients with interstitial lung disease

Background

Pulmonary hypertension (PH) is a serious complication to interstitial lung disease (ILD) and has a poor prognosis. PH is often diagnosed by screening with echocardiography followed by right heart catheterisation. A previous study has shown that a value of NT-pro-brain natriuretic peptide (NT-proBNP) <95 ng/l could be used to rule out PH in patients with ILD.

Aim

To evaluate this rule-out test for PH in a new cohort of incident patients with ILD.

Methods

An established database with data from 148 consecutive patients referred from January 2012 to October 2014 was used to identify patients and obtain data from echocardiography, NT-proBNP, diagnosis and lung function. Signs of PH on echocardiography were defined as a tricuspid pressure gradient (TR) ≥40 mmHg, decreased right ventricular systolic function or dilatation. Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of NT-proBNP >95 ng/l for signs of PH on echocardiography were calculated. The study was approved by the Danish Health Authority.

Results

In 118 patients, data from both echocardiography and measurements of NT-proBNP were available. Eleven of these were screened positive for PH on echocardiography. Sensitivity, specificity, NPV and PPV of NT-proBNP <95 ng/l for PH were 100, 44, 16 and 100%, respectively. Furthermore, no patients with left heart failure as the cause of dyspnoea were missed using this cut-off value.

Conclusion

NT-proBNP <95 ng/l precludes a positive echocardiographic screen for PH in ILD patients at referral for diagnostic workup.

Who should be referred to a specialist pulmonary -hypertension centre - a referrer's guide

The introduction of pulmonary hypertension (PH)-specific drugs has allowed certain forms of PH to become more treatable. However, patients with these diseases can present to a number of medical specialties and can be challenging to identify, particularly in a non-specialist setting. This article provides guidance on who should be investigated and referred on to a specialist centre, highlighting the potential pitfalls during assessment.

2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension

Guidelines summarize and evaluate all available evidence on a particular issue at the time of the writing process, with the aim of assisting health professionals in selecting the best management strategies for an individual patient with a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines and recommendations should help health professionals to make decisions in their daily practice. However, the final decisions concerning an individual patient must be made by the responsible health professional(s) in consultation with the patient and caregiver as appropriate.

Noninvasive identification of left-sided heart failure in a population suspected of pulmonary arterial hypertension

Exclusion of pulmonary hypertension secondary to left-sided heart disease (left heart failure (LHF)) is pivotal in the diagnosis of pulmonary arterial hypertension (PAH). In case of doubt, invasive measurements are recommended. The aim of the present study was to investigate whether it is possible to diagnose LHF using noninvasive parameters in a population suspected of PAH.300 PAH and 80 LHF patients attended our pulmonary hypertension clinic before August 2010, and were used to build the predictive model. 79 PAH and 55 LHF patients attended our clinic from August 2010, and were used for prospective validation.A medical history of left heart disease, S deflection in V1 plus R deflection in V6 in millimetres on ECG, and left atrial dilation or left valvular heart disease that is worse than mild on echocardiography were independent predictors of LHF. The derived risk score system showed good predictive characteristics: R(2)=0.66 and area under the curve 0.93. In patients with a risk score ≥72, there is 100% certainty that the cause of pulmonary hypertension is LHF. Using this risk score system, the number of right heart catheterisations in LHF may be reduced by 20%.In a population referred under suspicion of PAH, a predictive model incorporating medical history, ECG and echocardiography data can diagnose LHF noninvasively in a substantial percentage of cases.

Response to pulmonary arterial hypertension drug therapies in patients with pulmonary arterial hypertension and cardiovascular risk factors

The age at diagnosis of pulmonary arterial hypertension (PAH) and the prevalence of cardiovascular (CV) risk factors are increasing. We sought to determine whether the response to drug therapy was influenced by CV risk factors in PAH patients. We studied consecutive incident PAH patients (n = 146) between January 1, 2008, and July 15, 2011. Patients were divided into two groups: the PAH-No CV group included patients with no CV risk factors (obesity, systemic hypertension, type 2 diabetes mellitus, permanent atrial fibrillation, mitral and/or aortic valve disease, and coronary artery disease), and the PAH-CV group included patients with at least one. The response to PAH treatment was analyzed in all the patients who received PAH drug therapy. The PAH-No CV group included 43 patients, and the PAH-CV group included 69 patients. Patients in the PAH-No CV group were younger than those in the PAH-CV group (P < 0.0001). In the PAH-No CV group, 16 patients (37%) improved on treatment and 27 (63%) did not improve, compared with 11 (16%) and 58 (84%) in the PAH-CV group, respectively (P = 0.027 after adjustment for age). There was no difference in survival at 30 months (P = 0.218). In conclusion, in addition to older age, CV risk factors may predict a reduced response to PAH drug therapy in patients with PAH.

Electrocardiographic differences between COPD patients evaluated for lung transplantation with and without pulmonary hypertension

INTRODUCTION

Pulmonary hypertension (PH) is an indicator of poor prognosis in COPD patients; particularly in those with mean pulmonary artery pressure ≥ 40 mm Hg. Electrocardiography (ECG) might be useful for screening of this condition.

METHODS

Retrospective study of COPD patients evaluated for lung transplantation in whom we analyzed the 12-lead ECG performed closest to the time of right heart catheterization.

RESULTS

We included 142 patients. PH was present in 90 patients (63%) and 16 (11%) had a mean PAP ≥ 40 mmHg. The PR interval was longer in PH patients (151 (29) versus 139 (22) ms, p = 0.01) and T wave axis had a left shift (56.9 (32) versus 68.7 (19) degrees, p = 0.006). PR interval was longer (178.5 (35) versus 142.2 (23) ms, p = 0.001), T wave axis had a leftward deflection (63.6 (24) versus 42.8 (46) degrees, p = 0.005) and S wave in lead I was larger (0.19 (0.13) versus 0.12 (0.12) mV, p = 0.03) in patients with mean PAP ≥ 40 mmHg. A PR interval > 137 ms and S wave in DI > 0.02 mV had a sensitivity of 100% and a specificity of 59.5% to identify COPD patients with a mean PAP ≥ 40 mmHg.

CONCLUSION

There are significant ECG differences between advanced COPD patients with and without PH; however the ECG is an inadequate tool to differentiate between the groups. A prolonged PR interval suggests the presence of severe PH.

Electrocardiography at diagnosis and close to the time of death in pulmonary arterial hypertension

BACKGROUND

Scarce information exits on the electrocardiographic (ECG) characteristics of pulmonary arterial hypertension (PAH) patients close to their death and whether observed abnormalities progress from the time of PAH diagnosis.

METHODS

We analyzed the characteristics of the ECG performed at initial diagnosis, during the course of the disease and close to the time of death on consecutive PAH patients followed at our institution between June 2008 and December 2010.

RESULTS

We included 50 patients with PAH (76% women) with mean (SD) age of 58 (14) years. Median heart rate (83 vs 89 bpm, P = 0.001), PR interval (167 vs 176 ms, P = 0.03), QRS duration (88 vs 90 ms, P = 0.02), R/S ratio in lead V1 (1 vs 2, P = 0.01), and QTc duration (431 vs 444 ms, P = 0.02) significantly increased from the initial to the last ECG. In addition, the frontal QRS axis rotated to the right (97 vs 112 degrees, P = 0.003) and we more commonly observed right bundle branch block (5% vs 8%, P = 0.03) and negative T waves in inferior leads (31% vs 60%, P = 0.004). No patient had normal ECG at the time of death.

CONCLUSIONS

Significant changes progressively occur in a variety of ECG parameters between the time of the initial PAH diagnosis and close to death.

Predictors of diastolic-to-wedge gradient in patients evaluated for pulmonary hypertension

Background

Differentiation of pulmonary arterial hypertension (PAH) and pulmonary venous hypertension (PVH) often requires right heart catheterization (RHC). We sought to determine whether a combination of clinical and echocardiographic variables could predict the pulmonary diastolic to wedge (PAd-PWP) gradient and thus differentiate patients with PAH and PVH.

Methods

We prospectively enrolled 108 patients presenting for PH evaluation. We developed a multivariate model to predict PAd-PWP gradient and validated this model using bootstrapping technique.

Results

PAH patients had worse hemodynamics and were more likely to have evidence of right ventricular dilation and dysfunction whereas patients with PVH were older and more likely to have features of the metabolic syndrome. PAd-PWP gradient of ≥ 6mmHg accurately discriminated patients with PAH compared to PVH. Our model including clinical and echocardiographic variables was highly accurate for the prediction of PAd-PWP gradient with a slope 0.89 (slope of 1 represents perfect prediction).

Conclusions

In this prospective study of patients referred for PH evaluation, a model of readily available clinical parameters and simple echocardiographic measurements accurately predicted the PAd-PWP gradient, allowing discrimination of patients with PAH and PVH. This model requires validation in a larger cohort, but may afford clinicians more parsimony with referral for invasive testing in the evaluation of PH.

Diagnostic value of echocardiography in the diagnosis of pulmonary hypertension

AIMS

To determine the value of echocardiography including tissue Doppler imaging (TDI) and right ventricular (RV) speckle tracking analysis for the diagnosis of pulmonary hypertension (PH) and discrimination between pre- and postcapillary PH.

METHODS AND RESULTS

155 consecutive patients (mean age 70.5±13.0 years, 81 [52%] male gender, BMI 27.2±6.1 kg/m(2)) with PH undergoing right heart catheterization (RHC) and transthoracic echocardiography (TTE) with TDI between January 2008 and December 2009 were retrospectively evaluated including offline speckle tracking analysis of RV contractility. After RHC 23.2% of patients (36) were diagnosed with precapillary PH. Invasive results from RHC were significantly correlated to TTE measurements (E/é, postcapillary wedge pressure [PCWP], r=0.61, P<0.001; mean, systolic pulmonary arterial pressure [mPAP, sPAP], r=0.43, P<0.001). Single echocardiographic parameters were of good predictive value for final PH-diagnosis (sPAP, area under the curve [AUC] 0.63, P=0.025; lateral apical RV longitudinal strain [RVaSl)], AUC 0.76, P=0.001; E/é, AUC 0.84, P<0.001) which could be increased by combining most predictive parameters after receiver operating curves (ROC) cut off analysis (sPAP>69 mmHg, E/é<12, RVaSl ≥-8.4%). TTE had a sensitivity of 33.33% and a specificity of 100% to identify patients with precapillary PH, and a negative predictive value of 84.72% to rule out precapilary PH.

CONCLUSION

Echocardiography allows feasible and reliable estimation of PH and seems helpful to distinguish between pre-and postcapillary PH. Further prospective studies on patients with different manifestations of PH must validate the predictive value of echocardiography in this clinical setting.