Pulmonary artery dilatation correlates with the risk of unexpected death in chronic arterial or thromboembolic pulmonary hypertension.
BACKGROUND
Right ventricular failure does not explain all cases of death in patients with chronic pulmonary hypertension. Searching for alternative explanations, we evaluated the prognostic significance of main pulmonary artery (PA) dilatation in patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH).


METHODS
A retrospective outcome analysis was made of 264 patients (aged 46 ± 17 years; women, 69%; PAH, 82%) who underwent both CT scan measurement of the PA and right-sided heart catheterization (mean PA pressure, 57.6 ± 16.5 mm Hg) at initial evaluation.


RESULTS
The diameter of the PA ranged from 28 to 120 mm (mean, 39 ± 8.6 mm; median, 38 mm) and was largest in patients with unrepaired congenital defects (42.6 ± 7.6 mm). Pulmonary pulse pressure (P = .04), lower age (P = .03), and duration of symptoms (P &lt; .001) were independently but weakly related to PA diameter. During follow-up (median, 38 months), 99 patients (37%) died. Of these 99 deaths, 73 (74%) were due to heart failure or comorbidities, and 26 (26%) were unexpected deaths (UE-Ds). PA diameter (hazard ratio [HR], 1.06 per 1 mm; 95% CI, 1.03-1.08), heart rate (HR, 1.30 per 10 beats/min; 95% CI, 1.01-1.66), and systolic pulmonary arterial pressure (HR, 1.02 per 1 mm Hg; 95% CI, 1.01-1.04) were the only independent predictors of UE-D and differed from the usual predictors found in the study group for all-cause mortality. PA diameter ≥ 48 mm had 95% specificity and 39% sensitivity and carried 7.5 times higher risk of UE-D (95% CI, 3.4-16.5; P &lt; .0001) during follow-up.


CONCLUSIONS
PA dilatation emerges as an independent risk factor for death unexplained by right ventricular failure or comorbidities in patients with PAH and CTEPH. The possible mechanisms include, but are not limited to, PA compression of the left main coronary artery, PA rupture, or dissection with cardiac tamponade.
Department of Pulmonary Circulation and Thromboembolic Diseases, Medical Center of Postgraduate Education, European Health Centre, Otwock, Poland.
Joanna
J
Żyłkowska
Department of Pulmonary Circulation and Thromboembolic Diseases, Medical Center of Postgraduate Education, European Health Centre, Otwock, Poland.
Marcin
M
Kurzyna
Department of Pulmonary Circulation and Thromboembolic Diseases, Medical Center of Postgraduate Education, European Health Centre, Otwock, Poland.
Michał
M
Florczyk
Department of Radiology, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
Barbara
B
Burakowska
I Chair and Department of Cardiology, Medical University of Warsaw, Warsaw, Poland.
Franciszek
F
Grzegorczyk
Cardio-Pulmonary Intensive Care Medicine, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
Janusz
J
Burakowski
Department of Pulmonary Circulation and Thromboembolic Diseases, Medical Center of Postgraduate Education, European Health Centre, Otwock, Poland.
Maria
M
Wieteska
Department of Radiology, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
Karina
K
Oniszh
Department of Cardiac Surgery, Praski Hospital, Warsaw, Poland.
Andrzej
A
Biederman
Department of Chest Medicine, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
Liliana
L
Wawrzyńska
I Department of Pneumonology, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
Monika
M
Szturmowicz
Department of Radiology, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
Anna
A
Fijałkowska
Department of Pulmonary Circulation and Thromboembolic Diseases, Medical Center of Postgraduate Education, European Health Centre, Otwock, Poland. Electronic address: adam.torbicki@ecz-otwock.pl.
Adam
A
Torbicki
D000328:Adult; D002908:Chronic Disease; D003645:Death, Sudden / Q000453:epidemiology*; D065627:Familial Primary Pulmonary Hypertension; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006976:Hypertension, Pulmonary / Q000401:mortality* / Q000473:pathology / Q000503:physiopathology; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011651:Pulmonary Artery / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D011655:Pulmonary Embolism / Q000401:mortality* / Q000473:pathology / Q000503:physiopathology; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D014664:Vasodilation / Q000502:physiology*