4-((1,4,8,11-tetraazacyclotetradec-1-yl)methyl)benzoic acid

The Pulmonary Embolism Registry of Goettingen (PERGO) prospectively includes consecutive patients with objectively confirmed PE ≥ 18 years of age admitted to the University Medical Center Goettingen, Germany. The study protocol has been described in detail previously [16 (link), 17 (link)]. The present analysis included patients enrolled in PERGO between September 2008 and August 2016. Patients withdrawing previously given consent for participation in PERGO and patients included twice in PERGO because of recurrent PE were excluded from analysis. All patients were followed for the in-hospital stay and 1-year survival status was assessed by contacting the responsible registration offices.
Diagnostic and therapeutic management was in accordance with the ESC 2008 (09/2008–08/2014) and 2014 (09/2014–08/2016) guidelines [1 (link), 18 (link)] and local standard operating procedures. All related decisions were left to the discretion of the treating physicians and were not influenced by the study protocol. Treating physicians were not informed about study results, thus any influence of the study on patient management or monitoring of treatment effects during the follow-up period can be excluded.
Complete data on baseline characteristics, VTE risk factors and comorbidities, results from diagnostic examinations including imaging (CTPA and transthoracic echocardiography) and laboratory testing, treatment and in-hospital outcomes were obtained using a standardised questionnaire case report form. Acute reperfusion treatment was defined as systemic thrombolysis, surgical thrombectomy and interventional approaches. Early discharge was defined as discharge from hospital within 48 h. Further definitions used in the present study are provided in the Online Resource. Patients were classified to risk classes according to the algorithm proposed by the ESC 2014 guidelines [1 (link)], the simplified Pulmonary Embolism Severity Index (sPESI), the modified FAST score [19 (link)] and the Bova score [20 (link)]. For calculation of algorithms and scores, missing values were considered to be normal [19 (link)].
An in-hospital adverse outcome was defined as PE-related death, need for mechanical ventilation, cardiopulmonary resuscitation or administration of catecholamines. Further study outcomes include in-hospital all-cause death, duration of the in-hospital stay (days) and 1-year all-cause mortality. Death was determined to be PE-related if either confirmed by autopsy or following a clinically severe episode of acute PE in absence of an alternative diagnosis. All events and causes of death were independently adjudicated by two of the authors (M.E. and K.K.) and disagreement was resolved by a third author (M.L.).

The following data were collected from RIS‐PACS (radiology information systems and picture archiving and communication systems): type of thoracic CT performed which include CT Chest, CTPA or HRCT, clinical indication, positive or negative for pulmonary embolism (PE) if CTPA was performed and whether patient was urgently scanned. Normally, CT scans for COVID‐19 patients were scheduled to be performed after normal hours. We defined a scan urgent if the time of investigation was within 2 h of the CT request time by the ward clinician.
Electronic medical records were also reviewed to record the following data: demographic data including patient sex and age, days post‐COVID‐19 positive on PCR, length of admission at time of scan, if patient was staying in the intensive care unit (ICU) at time of scan and management plan pre‐ and post‐CT chest. A change in management was defined as when a medication was initiated or ceased, the patient was admitted to ICU, or a procedure was performed.
Western Sydney Local Health District (WSLHD) Human Research Ethics Committee approval for this study was obtained.