Diagnosing pulmonary hypertension: is there a revival of the electrocardiogram?

Even in the most recent and largest series of patients with pulmonary arterial hypertension (PAH), the time interval between the onset of symptoms and eventual diagnosis was a mean of 27 months 1. This represents an absolutely unacceptable delay, which is tragically even longer than the mean of 2 yrs in the first series of the US National Institutes of Health (NIH) registry about 20 yrs ago 2. Nowadays, three-quarters of patients are in World Health Organization (WHO) functional classes III or IV, have a 6-min walk distance of ∼330 m and a pulmonary vascular resistance of almost 1,000 dyn·s·cm−5 at the time of diagnosis 1. The mean pulmonary artery pressure ( P pa) of patients included in large randomised studies remains at values >50 mmHg, with 60 mmHg in the epoprostenol trial in 1996 3 and 52 mmHg in the Endothelin Antagonist Trial in Mildly Symptomatic Pulmonary Arterial Hypertension Patients (EARLY) study in 2008 4. Remarkably, the latter intended to include only patients in WHO class II, which implies that even patients with a clinically early form of the disease in fact suffer from an advanced stage of PAH, comparable to those in WHO functional class III–IV. Hence, despite advances in therapeutic options, there is no faint hope of improvement in diagnosing PAH during the past decades. Not unexpectedly, the overall 3-yr survival is still only ∼60% 5, 6, a modest 20% better than our ancestors’ empirical observations. Our poor diagnostic performance with respect to the two forms of pre-capillary pulmonary hypertension (PH), i.e. PAH and chronic thromboembolic PH, is even more surprising if one considers the obviousness of the clinical presentation. Although PH symptoms are nonspecific, there are hardly any differential diagnoses for the classical triad of 1) dyspnoea or fatigue on …