Introduction

Although PT is a frequent complication in COVID-19, its consequences remain unknown. We
aimed to evaluate whether PT is associated to higher cardiopulmonary complications.

Methods
All consecutive COVID-19 patients with at least one D Dimer >/= 1000 ng/mL underwent a
computed pulmonary angiography (CPA) which classified them by the presence of PT. After 6
months, clinical and laboratory characteristics were collected, and a 2nd CPA, an
echocardiogram, pulmonary function tests, and a 6-minute walking test (WT) were performed.

Results
112 patients (46 with PT) were followed up, among which the most common symptom was
dyspnea (38%). No differences were found regarding readmission or symptoms rates. Post-
COVID condition was only found in the non-PT group (9.4%). Forced vital capacity (93-101%),
forced expiratory volume in 1 second (95-105%), DLCO (73-87%), WT distance (440-576 m)
showed no differences between groups. Persistent thrombi were found in 4 patients (10.5%),
and new clots in 2 patients without previous PT. Parenchymal lung abnormalities were
observed in 69.9% of patients (ground glass opacifications (33.7%), fibrotic bands (24.1%),
septal thickening (25.3%), bronchiectasis (20.5%)). No differences were found between groups
in CPA findings, left ventricular ejection fraction, or pulmonary systolic pressure.

Conclusions
The prevalence of persistent dyspnea, parenchymal lung sequelae and mild impairment in
DLCO following COVID-19 was high, with no differences regarding the presence of PT. A total
of 6.7% of patients with PT had PH. The persistence of these alterations should be studied in
the long term.