COMPression of Left Main coRonary artEry in patientS With Pulmonary Arterial Hypertension aSymptomatIc fOr aNgina

Study Purpose

The prevalence of critical ab extrinsic compression of left main coronary artery (LMCA) is very high in patients with pulmonary arterial hypertension (PAH) symptomatic for angina (up to 40% according to a recent study of 121 patients with PAH). The element that most of all correlates with the degree of coronary stenosis is the diameter of the pulmonary artery (PA). In particular, a diameter ≥ 40 mm has a sensitivity of 83% and a specificity of 70% in patients with angina. Critical stenosis of LMCA is a risk factor for sudden death and in these condition percutaneous coronary angioplasty with stent implantation has proven to be a safe and effective long-term procedure. Preliminary data from a retrospective analysis of the registry of patients with PAH in Bologna (ARCA registry, 109/2016/U/Oss) highlights that even in PAH patients asymptomatic for angina, compression of LMCA can occur in up to 13% of patients and the main predictive parameter of compression was found to be a diameter ≥ 42 mm (with a sensitivity of 87% and a specificity of 77%). Performing a screening test by coronary-CT scan in all subjects suffering of PAH with a PA diameter ≥ 40 mm even if asymptomatic for angina could therefore help to identify patients with PAH at increased risk for sudden death at an early stage.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

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Eligible Ages 18 Years and Over
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - Patients with PAH (group 1 of World Health Organization pulmonary hypertension classification) who have undergone at least one pulmonary CT angiography with a PA trunk diameter ≥ 4 cm.
  • - Age ≥18 years.
  • - Asymptomaticity for angina pectoris or anginal equivalent.

Exclusion Criteria:

  • - Severe chronic kidney disease [Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) estimated glomerular filtration rate <30 ml/min) or need for dialysis.
  • - Major allergy to iodinated contrast agent.
  • - Intolerance or allergy to acetylsalicylic acid or clopidogrel.
  • - History of stroke or transient ischemic attack in the last 6 months or a history of intracranial haemorrhage.
  • - Known cerebral arteriovenous malformation or aneurysm.
  • - Known moderate or severe hepatic insufficiency (Child Pugh B or C) - Thrombocytopenia (<100.000/μL) or anemia (hemoglobin <10 g/dL) - Active bleeding or factors which, in the investigator's judgment, significantly increase the risk of bleeding.
  • - Major surgery in the past 30 days.
  • - Cancer in the active phase.
  • - Pregnancy or breastfeeding.
  • - Patient prognosis <1 year in the opinion of the investigator.
  • - Any condition that increases the risk of non-compliance or of being lost to follow-up.
  • - Patients who have already undergone a LMCA angioplasty.
- Failure to obtain informed consent

Trial Details

Trial ID:

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Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

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Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

IRCCS Azienda Ospedaliero-Universitaria di Bologna
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Fabio Dardi, PhD, MD
Principal Investigator Affiliation IRCCS Azienda Ospedaliero-Universitaria di Bologna (Italy)
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Recruiting
Countries Italy

The disease, disorder, syndrome, illness, or injury that is being studied.

Pulmonary Arterial Hypertension
Arms & Interventions


Experimental: Coronary-CT

Patients with PAH, asymptomatic for angina, with a PA trunk diameter ≥ 4 cm that undergo a coronary-CT scan examination


Radiation: - Coronary CT angiography

A coronary CT angiography will be used to study the relationship between the PA and the LMCA and 4 radiological patterns will be considered: "Normal": minimum distance between the two vessels> 1 mm; "Proximity": distance between the two vessels ≤1 mm without displacement or stenosis of the LMCA; "Dislocation": dislocation of the LMCA by the main branch of the PA with a take-off angle <60 ° (the take-off angle is defined by the angle formed by the perpendicular to the aortic valve ring and the longitudinal axis of the LMCA); "Compression": stenosis of the LMCA ≥50% due to extrinsic compression by the PA.

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International Sites

Bologna, Italy




IRCCS Azienda Ospedaliero-Universitaria di Bologna

Bologna, , 40138

Site Contact

Fabio Dardi, MD, PhD


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