Abstract
Background and aim
In this study we evaluated the impact of the updated pulmonary hypertension (PH) definitive criteria proposed in 6th World PH Symposium (WSPH) on numbers and frequencies of and pre- versus post-capillary PH as compared to those in European Society of Cardiology (ESC) 2015 PH Guidelines.
Methods
Study group comprised the retrospectively evaluated 1299 patients (pts) (age 53.1±18.8 years, female 807, 62.1%) who underwent right heart catheterisation (RHC) with different indications between 2006 and 2018. For ESC and WSPH PH definitions, pulmonary arterial mean pressure (PAMP) ≥25 mmHg (definition-A) and PAMP >20 mmHg (definition-B) RHC criteria were used, respectively. For pre-capillary PH definitions, pulmonary artery wedge pressure (PAWP) ≤15 mmHg and pulmonary vascular resistance (PVR) ≥3 Wood units criteria were included in the both definitions.
Results
In RHC assessments, PAMP ≥25 mmHg and >20 mmHg were noted in 891 (68.6%) and 1051 (80.9%) of overall pts, respectively. Moreover, pre-capillary PH was diagnosed in 284 (21.8%) and 298 (22.9%) with definition-A and B, respectively. Although updated WSPH definition was associated with a net 12.3% and a relative 18% increase in the overall PH diagnosis, net and relative changes in the frequency of the pre-capillary PH were only 1% and 4.9%. Increase in the overall PH with updated WSPH criterias compared to previous ESC definitions was associated with increase in the number of pre-capillary PH (n=298, 22.9%) but not in the overall frequency of post-capillary PH (688, 52.9%). Because PVR was the product of the transpulmonary gradient (PAMP minus PAWP) divided by cardiac output, this measure was found to keep specificity for distinction between pre- versus post-capillary PH even after lowering thetreshold diagnostic for PAMP from 25 to 20 mmHg.
Conclusions
Although updated WSPH definition was associated with net 12.3% and relative 18% increase in the overall PH diagnosis, its impact on frequencies of pre- versus post-capillary PH within overall PH population was negligible.These seem to be due to critical role of PVR ensuring specificity in pre-capillary PH diagnosis even after lowering the definitive PAMP treshold to 20 mmHg.