Orthostatic hypotension in precapillary pulmonary hypertension: prevalence, clinical profile and hemodynamic mechanisms
Notice bibliographique
Résumé
Precapillary Pulmonary Hypertension (PreCapPH) is a rare condition that progresses with impaired right ventricular (RV) function due to elevated RV afterload. Current PreCapPH pharmacological treatments often produce undesirable systemic vasodilatory effects. Furthermore, patients with PreCapPH exhibit reduced arterial baroreflex sensitivity and effectiveness. Collectively, these factors may compromise the regulation of systemic arterial pressure in PreCapPH, particularlyin response to sudden postural changes such as transitioning from lying to standing. However, orthostatic hypotension (OH) has only been indirectly interpreted via the Valsalva maneuver in a small cohort of patients with PreCapPH. Furthermore, evidence from other patient groups shows that OH occurrence is often poorly correlated with resting systemic arterial pressure and may be asymptomatic in up to 50% of cases. These findings suggest that OH could be an underrecognized yet clinically relevant issue in PreCapPH. The present study, therefore, sought to: 1) investigate the prevalence of OH and its subtypes (initial, delayed, and sustained OH) in patients with PreCapPH; 2) characterize the clinical profile of patients with PreCapPH who experience OH and its subtypes; and 3) explore hemodynamic mechanisms underlying the different OH subtypes in this patient population. Sixty outpatients with PreCapPH participated in the study. OH was verified by an active standing maneuver. Beat-by-beat heart rate and arterial pressure were measured by electrocardiography and volume clamp finger photoplethysmography, respectively. Stroke volume (SV) was estimated from the arterial pressure waveform, and cardiac output (CO) and total peripheral resistance (TPR) were calculated considering heart rate (HR), SV, and mean arterial pressure data. Initial OH was defined as a decrease in systolic arterial pressure (SAP) or diastolic arterial pressure (DAP) exceeding 40 or 20 mmHg within the first 15 seconds of standing. Delayed OH was defined as SAP or DAP decreases greater than 20 or 10 mmHg within 30 to 40 seconds, and sustained OH was identified as SAP or DAP decreases exceeding 20 or 10 mmHg between 60 and 600 seconds. Thirty-one patients had some type of OH (i.e., prevalence = 51.6%), with 19 presenting more than one OH subtype. Among these 31 patients with OH, 23 presented initial, 18 delayed, and 13 sustained OH. No significant differences were found between patients with and without OH regarding sex, age, resting pulmonary hemodynamics, resting arterial pressure, medications, functional class, and aerobic exercise capacity (P > 0.05). HR, SV, CO, and TPR responses (% change from supine baseline) were not different between groups with initial OH and without OH from the beginning to the end of standing (P > 0.05). However, SV decay was greater in the group with delayed OH than without OH (-31 ± 21 vs. -19 ± 14%; P = 0.033). Additionally, TPR compensatory increase was attenuated in the group with sustained OH than without OH (-6 ± 21 vs. 7 ± 15%; P = 0.023). In sum, patients with PreCapPH frequently experience OH when transitioning from a supine to a standing position, with initial OH being the most common subtype. Notably, no specific clinical characteristic was associated with OH occurrence. Initial OH did not appear to result from a single, identifiable hemodynamic mechanism. In contrast, delayed OH was linked to an exaggerated SV decay, while sustained OH was associated with insufficient TPR increase. CAPES; FAPESP, Numbers: 17/17027-0, 22/12176-5; CNPq, Numbers: 307610/2022-5, 313284/2021-0; NSERC Canada; Foundation Institut Universitaire Cardiologie Pneumologie This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».