Impact of the updated hemodynamic definitions on diagnosis rates of pulmonary hypertension

Remembering the Occam's Razor: Could Simple Electrocardiographic Findings Provide Relevant Predictions for Current Hemodynamic Criteria of Pulmonary Hypertension?

BACKGROUND

We evaluated the predictive value of electrocardiographic (ECG) findings for pulmonary hemodynamics assessed by right heart catheterization (RHC).

METHODS

Our study population comprised 562 retrospectively evaluated patients who underwent RHC between 2006 and 2022. Correlations between ECG measures and pulmonary arterial systolic and mean pressures (PASP and PAMP) and pulmonary vascular resistance (PVR) were investigated. Moreover, receiver operating characteristic (ROC) curve analysis assessed the predictive value of ECG for pulmonary hypertension (PH) and precapillary PH.

RESULTS

The P-wave amplitude (Pwa) and R/S ratio (r) in V1 and V2, Ra in augmented voltage right (aVR), right or indeterminate axis, but not P wave duration (Pwd) or right bundle branch block (RBBB) significantly correlated with PASP, PAMP, and PVR (P <.001 for all). The partial R2 analysis revealed that amplitude of R wave (Ra) in aVR, R/Sr in V1 and V2, QRS axis, and Pwa added to the base model provided significant contributions to variance for PASP, PAMP, and PVR, respectively. The Pwa > 0.16 mV, Ra in aVR > 0.05 mV, QRS axis > 100° and R/Sr in V1 > 0.9 showed the highest area under curve (AUC) values for PAMP > 20 mm Hg. Using the same cutoff value, Ra in aVR, Pwa, QRS axis, and R/Sr in V1 showed highest predictions for PVR > 2 Wood Units (WU).

CONCLUSION

In this study, Pwa, Ra in aVR, right or indeterminate axis deviations, and R/Sr in V1 and V2 showed statistically significant correlations with pulmonary hemodynamics, and Ra in aVR, R/Sr in V2 and V1, QRS axis, and Pwa contributed to variance for PASP, PAMP, and PVR, respectively. Moreover, Pwa, Ra in aVR, QRS axis, and R/Sr in V1 seem to provide relevant predictions for PH and precapillary PH.

Significance of Hypocapnia in the Risk Assessment of Patients with Pulmonary Hypertension

Blood gas analysis is part of the diagnostic work-up for pulmonary hypertension (PH). Although some studies have found that the partial pressure of carbon dioxide (PaCO2) is an independent marker of mortality in individuals with pulmonary arterial hypertension (PH Group 1), there is a lack of data regarding the significance of PaCO2 in individuals with different types of PH based on the new 2022 definitions. Therefore, this study analyzed data from 157 individuals who were undergoing PH work-up, including right heart catheterization, using PH definitions from the 2022 European Society of Cardiology/European Respiratory Society guidelines. At diagnosis, N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels were significantly higher, but the time-course of NT-pro-BNP levels during treatment was significantly more favorable in individuals with pulmonary arterial hypertension (PH Group 1) who did versus did not have hypocapnia (p = 0.026 and p = 0.017, respectively). These differences based on the presence of hypocapnia were not seen in individuals with PH Groups 2, 3, or 4. In conclusion, using the new definition of PH, hypocapnia may correlate with worse risk stratification at diagnosis in individuals with pulmonary arterial hypertension. However, hypocapnic individuals with pulmonary arterial hypertension may benefit more from disease-specific therapy than those without hypocapnia.

The definition of pulmonary hypertension: history, practical implications and current controversies

The definition of pulmonary hypertension (PH) is based on a growing body of evidence and represents the result of ongoing discussions within the PH community over the past 50 years. In 2018, the most recent World Symposium on Pulmonary Hypertension introduced significant changes in the definition of PH by lowering the mean pulmonary arterial pressure threshold to >20 mmHg and (re)introducing the pulmonary vascular resistance ≥3 WU cut-off for all forms of pre-capillary PH. These changes and their potential clinical impact have been the subject of lively discussions in the community and some important questions and controversies have been identified.

In this review we aim to present the development of the definition of PH over the past decades and discuss the main arguments that led to relevant modifications. In addition, we address the practical implications of the most recent changes and controversies that still exist.

The definitions of PH and PAH reflect the upper limit of normal haemodynamic values, their prognostic relevance and practical considerations. With appropriate clinical context they represent the cornerstone of PH diagnosis and clinical decision making.https://bit.ly/3gRSyWz

Impact of the revised hemodynamic definition on the diagnosis of precapillary pulmonary hypertension: a retrospective single-center study in China

Background

In the 6^th World Symposium on Pulmonary Hypertension (PH), the hemodynamic definition of PH was reduced from a mean pulmonary artery pressure (mPAP) ≥25 to >20 mmHg. This study aimed to evaluate the impact of the revised hemodynamic definition on the diagnosis of precapillary PH.

Methods

We retrospectively enrolled patients who underwent right heart catheterization from January 2012 to December 2018. All included patients were reassessed according to the revised hemodynamic definition.

Results

A total of 1,251 patients were included for analysis, of whom 1,044 patients had precapillary PH and 182 patients had mPAP <25 mmHg. After applying the revised definition, 33 (18.1%) of 182 patients with mPAP <25 mmHg were reclassified as having PH. However, only 7 of these 33 patients had a pulmonary vascular resistance ≥3 wood units and could be considered to have precapillary PH, accounting for 0.7% of the existing precapillary PH population. More importantly, 12 patients with mPAP ≥25 mmHg were delisted from precapillary PH for pulmonary vascular resistance <3 wood units (5 patients from Group III, 4 patients from Group IV, 3 patients from Group V). Overall, there was a net 0.5% decrease [(12-7)/1044×100%] in the population with precapillary PH.

Conclusions

The revised hemodynamic definition had a minor impact on the diagnosis of precapillary PH. It should be noted that the revised definition would influence not only patients with mPAP =21-24 mmHg, but also patients with mPAP ≥25 mmHg.

Effect of Group 2 Pulmonary Hypertension Subgroups on Outcomes: Impact of the Updated Definition of Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is a common complication of end-stage heart failure (ESHF) and associated with increased mortality. The definition of PH has recently been changed from a mean pulmonary arterial pressure (PAPm) ≥25 mmHg to a PAPm >20 mmHg. Since this change, there are no data evaluating group 2 PH subgroups on outcomes. The purpose of this study was to determine the impact of updated group 2 PH subgroups on outcomes, as well as to evaluate the clinical, echocardiographic, and haemodynamic characteristics of subgroups, and determine predictors of PH in patients with ESHF.

METHOD

A total of 416 patients with ESHF with left ventricle ejection fraction (LVEF) ≤25% were divided into three groups. Pulmonary hypertension was defined as PAPm >20 mmHg. Primary outcome was defined as left ventricular assist device (LVAD) implantation, urgent heart transplantation (HT), or death. Secondary outcome was defined as LVAD implantation and HT.

RESULTS

Over a median follow-up of 503.5 days, combined pre- and postcapillary PH (Cpc-PH) displayed greater risk of primary outcome than those with isolated postcapillary (Ipc-PH) (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.29-1.91; p<0.001) and those with no PH (HR, 2.47; 95% CI, 1.68-3.63; p<0.001). Patients with Ipc-PH demonstrated greater risk than those with no PH (HR, 1.57; 95% CI, 1.57-1.90; p<0.001). Likelihood ratios of updated PH criteria and old PH criteria (PAPm ≥25 mmHg) in identifying primary outcome were 75.6 (R²=0.179) and 72.09 (R²=0.164). Patients with PAPm 21-24 mmHg had a higher primary outcome than those with PAPm ≤20 mmHg. Severe mitral regurgitation, LVEF, grade 3 diastolic dysfunction, diabetes, and cardiac output were predictors of PH.

CONCLUSIONS

Pulmonary hypertension increases the risk of LVAD, urgent HT, or death, and Cpc-PH further increases risk in patients with ESHF. Compared to the previous definition, a new PH definition better discriminates death, going to urgent HT, or LVAD implantation for PH subgroups.