Die frühe Diagnose und Therapie der pulmonalen Hypertonie – Aspekte einer Vision

Zusammenfassung

Im Rahmen einer zusammenfassenden Darstellung der Ergebnisse eines Expertentreffens wird zu ausgewählten Problemen bei der Frühdiagnostik der Patienten mit pulmonaler Hypertonie (PH), den ersten Daten bei frühzeitigem Behandlungsbeginn und den vorliegenden Erfahrungen bei der Ableitung von Prognose- bzw. Zielkriterien Stellung genommen.

Die aktuelle Definition einer manifesten PH anhand eines mittleren pulmonalarteriellen Druckes ≥ 25 mmHg in Ruhe stellt für die meisten PH-Formen kein frühes Stadium der Erkrankung dar. Es gibt zunehmende Evidenz dafür, dass sich eine frühe PH durch die Überschreitung eines niedrigen Grenzwertes des pulmonalarteriellen Druckes oder einen überproportionalen Anstieg des Druckes in Beziehung zum Herzzeitvolumen unter körperlicher Belastung manifestiert. Neben dem als Goldstandard geltenden Rechtsherzkatheter werden in der Praxis mehrere diagnostische Methoden zur Erfassung einer frühen PH genutzt, von denen der Echokardiografie besondere Bedeutung beigemessen wird.

Die gezielte medikamentöse Behandlung ist aktuell nur für PH-Patienten der WHO-Gruppe I (Pulmonale Arterielle Hypertonie, PAH) überwiegend ab einer funktionellen Klasse (FC) II zugelassen. Erste Pilotstudien legen den Einsatz der zur Verfügung stehenden Substanzen in kontrollierten Therapiestudien schon bei Patienten in der FC I nahe.

In der klinischen Praxis werden zur Beschreibung von „Therapiezielen“ bei der Behandlung der PH überwiegend Faktoren mit relevanter prognostischer Bedeutung gewählt, wobei der Analyse meist retrospektive Daten zugrunde lagen, die oft nicht prospektiv geprüft wurden. Die für ein solches Vorgehen eigentlich notwendigen Studien fehlen bisher. Für die Patienten in der FC I existieren nicht einmal retrospektive Daten. Vor diesem Hintergrund ist verständlich, dass spezifische Zielkriterien für die Behandlung von frühen Formen der PH derzeit (noch) nicht zur Verfügung stehen.

Abstract

In patients with pulmonary hypertension progressive vascular changes in the lung precede the clinical and hemodynamic manifestations of the disease. Therefore, early diagnosis and timely treatment of the disease are crucial. This has been the topic of an expert meeting in Greifswald, Germany in June 2012.

The current definition of pulmonary hypertension requires a mean pulmonary artery pressure ≥ 25 mmHg at rest, a hemodynamic abnormality already reflecting pulmonary vascular changes beyond early disease. There is increasing evidence supporting the concept that a lower pressure threshold at rest or an abnormal pressure response with exercise better characterize early disease. While right heart catheterization at rest remains the diagnostic gold standard other methods for detecting early disease are explored with echocardiography being the most frequently used technique.

Targeted therapy has been approved for patients with pulmonary arterial hypertension (PAH, WHO-group I) in functional class II-IV. Preliminary data in functional class I patients suggest therapeutic potential of theses drugs in early disease as well.

Current guidelines propose therapeutic goals based on parameters with prognostic importance. However, these recommendations are based on mostly retrospective analyses of pre-treatment data obtained in patients with pulmonary hypertension in functional class II–IV. Therefore, evidence-based therapeutic goals for early interventions in functional class I patients are lacking.

^* im Namen der Teilnehmer der Greifswald Konferenz für frühe pulmonale Hypertonie.

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