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Prognostic Relevance of Tricuspid Annular Plane Systolic Excursion to Systolic Pulmonary Arterial Pressure Ratio and Its Association With Exercise Hemodynamics in Patients With Normal or Mildly Elevated Resting Pulmonary Arterial Pressure

BACKGROUND

Echocardiographic tricuspid annular plane systolic excursion (TAPSE) to systolic pulmonary arterial pressure (sPAP) ratio is a noninvasive surrogate for right ventricle (RV)-pulmonary arterial (PA) coupling. It has been related to outcome in patients with moderate to severe pulmonary hypertension (PH).

RESEARCH QUESTION

Is RV-PA coupling of prognostic relevance in patients with suspected PH, but only normal or mildly elevated mean pulmonary arterial pressure (mPAP), and is it associated with impaired exercise capacity and exercise hemodynamics?

STUDY DESIGN AND METHODS

Patients with mPAP of < 25 mm Hg who underwent echocardiography and exercise right heart catheterization in our PH clinic were analyzed retrospectively. Mild PH was defined as mPAP of 21 to 24 mm Hg and exercise PH (EPH) was defined as a mPAP to cardiac output (CO) slope of > 3 mm Hg/L/min. Multivariate analysis was performed to identify independent predictors for clinical worsening (CW), defined by disease-related hospitalization, transplantation, or death.

RESULTS

Two hundred thirty-seven patients (155 female with median age, 64 years [interquartile range (IQR), 54-73 years]; no PH: n = 147; mild PH: n = 90; EPH: n = 202) were included. During the observation time of 63 months (IQR, 29-104 months), 36 patients died and 126 clinical worsening events occurred. TAPSE to sPAP ratio was an age- and sex-independent predictor of mortality (hazard ratio [HR], 0.09; 95% CI, 0.01-0.62; P = .014) and clinical worsening (HR, 0.05; 95% CI, 0.35-0.78; P = .002). TAPSE to sPAP ratio also was correlated significantly to 6-min walk distance (r = 0.33; P < .001) and exercise hemodynamics (mPAP to CO slope: rρ = -0.56; P < .001). The best multivariate predictive model for clinical worsening in this population consisted of TAPSE to sPAP ratio (HR, 0.71; 95% CI, 0.53-0.95; P = .021), N-terminal pro-brain natriuretic peptide (HR, 1.15; 95% CI, 0.99-1.34; P = .065), and 6-min walk distance (HR, 0.998; 95% CI, 0.995-1.00; P = .042).

INTERPRETATION

Our results indicate that in patients with suspected PH, but normal or only mildly elevated resting mPAP, TAPSE to sPAP ratio is an independent predictor of outcome. In addition, it is associated significantly with exercise capacity and exercise hemodynamics and may be a helpful tool in the prediction of future clinical worsening of this patient population.

Screening and diagnosis of pulmonary hypertension associated with chronic lung disease (PH-CLD): A consensus statement from the pulmonary vascular research institute's innovative drug development initiative-group 3 pulmonary hypertension

Pulmonary hypertension (PH) is a frequent complication of chronic lung disease (CLD). However, PH is difficult to diagnose early since accompanying symptoms overlap and are similar to those of the underlying CLD. In most cases the PH is mild to moderate and therefore physical signs may be absent or subtle. This consensus paper provides insight into the clues that might suggest the presence of occult PH in patients with CLD. An overview of current diagnostic tools and emerging diagnostic technologies is provided as well as guidance for the work-up and diagnosis of PH in patients with CLD.

Definition, classification and diagnosis of pulmonary hypertension

Pulmonary hypertension (PH) is a haemodynamic condition characterised by elevation of mean pulmonary arterial pressure (mPAP) >20 mmHg, assessed by right heart catheterisation. Pulmonary arterial wedge pressure (PAWP) and pulmonary vascular resistance (PVR) distinguish pre-capillary PH (PAWP ≤15 mmHg, PVR >2 Wood Units (WU)), isolated post-capillary PH (PAWP >15 mmHg, PVR ≤2 WU) and combined post- and pre-capillary PH (PAWP >15 mmHg, PVR >2 WU). Exercise PH is a haemodynamic condition describing a normal mPAP at rest with an abnormal increase of mPAP during exercise, defined as a mPAP/cardiac output slope >3 mmHg/L/min between rest and exercise. The core structure of the clinical classification of PH has been retained, including the five major groups. However, some changes are presented herewith, such as the re-introduction of "long-term responders to calcium channel blockers" as a subgroup of idiopathic pulmonary arterial hypertension, the addition of subgroups in group 2 PH and the differentiation of group 3 PH subgroups based on pulmonary diseases instead of functional abnormalities. Mitomycin-C and carfilzomib have been added to the list of drugs with "definite association" with PAH. For diagnosis of PH, we propose a stepwise approach with the main aim of discerning those patients who need to be referred to a PH centre and who should undergo invasive haemodynamic assessment. In case of high probability of severe pulmonary vascular disease, especially if there are signs of right heart failure, a fast-track referral to a PH centre is recommended at any point during the clinical workup.