Abstract
BackgroundTo investigate if acute pulmonary vasodilation by sildenafil improves right ventricular function in patients with acute intermediate-high risk pulmonary embolism (PE).MethodsSingle center, explorative trial. Patients with PE were randomized to a single oral dose of sildenafil 50 mg (n = 10) or placebo (n = 10) as add-on to conventional therapy. The time from hospital admission to study inclusion was 2.3 ± 0.7 days. Right ventricular function was evaluated immediately before and shortly after (0.5–1.5 h) randomization by right heart catheterization (RHC), trans-thoracic echocardiography (TTE), and cardiac magnetic resonance (CMR). The primary efficacy endpoint was cardiac index measured by CMR.ResultsPatients had acute intermediate-high risk PE verified by computed tomography pulmonary angiography, systolic blood pressure of 135 ± 18 (mean ± SD) mmHg, increased right ventricular/left ventricular ratio 1.1 ± 0.09 and increased troponin T 167 ± 144 ng/L. Sildenafil treatment did not improve cardiac index compared to baseline (0.02 ± 0.36 l/min/m2, p = 0.89) and neither did placebo (0.00 ± 0.34 l/min/m2, p = 0.97). Sildenafil lowered mean arterial blood pressure (− 19 ± 10 mmHg, p < 0.001) which was not observed in the placebo group (0 ± 9 mmHg, p = 0.97).ConclusionA single oral dose of sildenafil 50 mg did not improve cardiac index but lowered systemic blood pressure in patients with acute intermediate-high risk PE. The time from PE to intervention, a small patient sample size and low pulmonary vascular resistance are limitations of this study that should be considered when interpreting the results.Trial Registration: The trial was retrospectively registered at www.clinicaltrials.gov (NCT04283240) February 2nd 2020, https://clinicaltrials.gov/ct2/show/NCT04283240?term=NCT04283240&draw=2&rank=1.
Highlights
To investigate if acute pulmonary vasodilation by sildenafil improves right ventricular function in patients with acute intermediate-high risk pulmonary embolism (PE)
Patients Patients with acute pulmonary embolism confirmed by contrast enhanced computed tomography (CT) were eligible for inclusion if they had symptom duration of less than 14 days, were older than 18 years and had a right ventricular/left ventricular ratio (RV/LV) > 1 measured by trans-thoracic echocardiography (TTE, 1 cm above the atrio-ventricular valves in the four-chamber view at end-diastole)
Patients were excluded if they were pregnant, had cardiac arrest that required cardiopulmonary resuscitation, a life expectancy < 120 days, systolic blood pressure < 90 mmHg, metal implants, obesity or claustrophobia that excluded the patient from cardiac magnetic resonance (CMR), altered mental status making the patient unable to provide informed consent, recent use of drugs with influence on the nitric oxide (NO)-cyclic guanosine mono phosphate (cGMP) pathway, known or suspected chronic thromboembolic pulmonary hypertension, inability to perform study protocol < 72 h after conventional PE treatment was instituted or active bleeding after thrombolysis
Summary
To investigate if acute pulmonary vasodilation by sildenafil improves right ventricular function in patients with acute intermediate-high risk pulmonary embolism (PE). Acute pulmonary embolism (PE) is a potentially fatal disease with a broad spectrum of clinical presentations. It may vary from subtle changes in functional capacity to hemodynamic collapse and death depending on the thromboembolic mass obstructing the pulmonary circulation and the associated vasoactive response of the Andersen et al BMC Pulm Med (2021) 21:72 pulmonary arteries. The treatment of choice is based on the severity of hemodynamic changes and the degree of right ventricular dysfunction. PE is still a fatal disease with a high risk of death in patients with intermediate or high-risk PE [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
