Incidence of Chronic Thromboembolic Pulmonary Hypertension after Pulmonary Embolism

Pengo, Vittorio
Lensing, Anthonie W.A.
Prins, Martin H.
Marchiori, Antonio
Davidson, Bruce L.
Tiozzo, Francesca
Albanese, Paolo
Biasiolo, Alessandra
Pegoraro, Cinzia
Iliceto, Sabino
Prandoni, Paolo

For the Thromboembolic Pulmonary Hypertension Study Group*
From the Department of Clinical and Experimental Medicine, Division of Clinical Cardiology (V.P., A.B., C.P., S.I.) and the Department of Medical and Surgical Sciences, Clinica Medica II (A.M., P.P.), and the Division of Geriatric Medicine (F.T., P.A.), University Hospital of Padua, Padua, Italy; the Department of Vascular Medicine, Academic Medical Center, Amsterdam, the Netherlands (A.W.A.L.); the Department of Clinical Epidemiology and Medical Technology Assessment, Academic Hospital, University of Maastricht, Maastricht, the Netherlands (M.H.P.); and the Division of Pulmonary and Critical Care Medicine, University of Washington and Swedish Medical Center, Seattle (B.L.D.). Address reprint requests to Dr. Lensing at the Department of Vascular Medicine, Academic Medical Center F4-211, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands, or at [email protected].
*Other members of the Thromboemolic Pulmonary Hypertension Study Group are listed in the Appendix.

New England Journal of Medicine 350(22):p 2257-2264, May 27, 2004. | DOI: 10.1056/NEJMoa032274

Background

Chronic thromboembolic pulmonary hypertension (CTPH) is associated with considerable morbidity and mortality. Its incidence after pulmonary embolism and associated risk factors are not well documented.

Methods

We conducted a prospective, long-term, follow-up study to assess the incidence of symptomatic CTPH in consecutive patients with an acute episode of pulmonary embolism but without prior venous thromboembolism. Patients with unexplained persistent dyspnea during follow-up underwent transthoracic echocardiography and, if supportive findings were present, ventilation-perfusion lung scanning and pulmonary angiography. CTPH was considered to be present if systolic and mean pulmonary-artery pressures exceeded 40 mm Hg and 25 mm Hg, respectively; pulmonary-capillary wedge pressure was normal; and there was angiographic evidence of disease.

Results

The cumulative incidence of symptomatic CTPH was 1.0 percent (95 percent confidence interval, 0.0 to 2.4) at six months, 3.1 percent (95 percent confidence interval, 0.7 to 5.5) at one year, and 3.8 percent (95 percent confidence interval, 1.1 to 6.5) at two years. No cases occurred after two years among the patients with more than two years of follow-up data. The following increased the risk of CTPH: a previous pulmonary embolism (odds ratio, 19.0), younger age (odds ratio, 1.79 per decade), a larger perfusion defect (odds ratio, 2.22 per decile decrement in perfusion), and idiopathic pulmonary embolism at presentation (odds ratio, 5.70).

Conclusions

CTPH is a relatively common, serious complication of pulmonary embolism. Diagnostic and therapeutic strategies for the early identification and prevention of CTPH are needed.

N Engl J Med 2004;350

2257-64.