Clinical Trial: Imaging Silent Brain Infarct And Thrombosis in Acute Myocardial Infarction

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: A Prospective, Observational Study to Assess the Efficacy of New Quantitative Imaging Methods to Assess the Risk of Acute and Subacute Thromboembolic Complications of Myocardial Infarction

Brief Summary: This project aims to assess the ability of cardiac imaging (cardiac MRI and Doppler-echocardiography) post-processing tools to predict a combined end-point of intraventricular thrombosis, silent brain infarcts, clinical stroke and peripheral arterial embolism in patients with first acute myocardial infarction and ventricular dysfunction.

Detailed Summary: An acute myocardial infarction (AMI) is a clinical situation that entails an increased risk of both subclinical and clinically devastating cardioembolic events. This increased risk of embolic phenomena may be related to blood stasis caused by alterations in the blood flow inside the left ventricle (LV) after AMI. Using flow velocity measurements obtained by cardiac MRI and Doppler-echocardiography it is possible to quantify the stasis in the LV and assess its relation to the risk of embolic events. The ability of cardiac imaging (cardiac MRI and Doppler-echocardiography) post-processing tools to predict embolic events in a cohort of 92 patients with a first AMI and left ventricular dysfunction shall be addressed. The potential confusion generated by the possible existence of paroxysmal AF will be controlled by implanting cardiac monitoring devices in random order in a subset of patients.
Sponsor: Hospital General Universitario Gregorio Marañon

Current Primary Outcome: Combined binary variable consisting of one of the following: ventricular thrombosis assessed by cardiac MRI, silent brain infarct detected by brain MRI, peripheral acute arterial embolism or ischemic stroke within the 6 months after a first STEMI [ Time Frame: 6 months ]

Individual outcome measurements as described in Secondary Outcome Measures Section


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Left ventricle mural thrombosis assessed by cardiac MRI performed one week and 6 months after STEMI [ Time Frame: 6 months ]
    Left ventricle mural thrombosis will be assessed by contrast cardiac MRI. Early after gadolinium contrast administration (3 min), two dimensional T1-weighted fast-field-echo sequences with an inversion-recovery prepulse will be used. A long inversion time (520 ms) will be used to identify intraventricular thrombus as a LV mass with low-signal intensity surrounded by high-signal intensity structures
  • Silent brain infarcts (SBI) within the 6 months following a first STEMI [ Time Frame: 6 months ]
    SBIs diagnosis entails the presence of a focal lesion > 3 mm that meets one of the three following criteria: 1) high signal on DWI isotropic images and low signal on the map of apparent diffusion coefficient (ADC). DWI sequence allows to detecting ischemic lesions (4 hours) and assessing their chronology. (2) cavitary lesion hyperintense on T2, with no signal (or low) in the FLAIR sequence usually surrounded by a ring gliotic hyperintense, hypointense on T1). (3) hyperintense lesion on T2 / T1 hypointense with prior distribution defect known or new in a follow-up study. The studies will be interpreted by a neuroradiologist blinded to clinical and echocardiographic information. For the assessment of whether the brain infarct is clinically silent, a medical history and physical examination focused on neurological symptoms will be performed including for that purpose the National Institute of Health (USA) questionnaire
  • Peripheral acute arterial embolism (limb or visceral) within the 6 months following a first STEMI [ Time Frame: 6 months ]
    Incidence of acute limb ischemia (characterized by pain, pallor, pulselessness, poikilothermia, paresthesias, paralysis) and/or acute visceral ischemia (renal or mesentheric acute isquemia) within the 6 months following a first STEMI, as confirmed by clinically-indicated imaging technique.
  • Ischemic stroke within the 6 months after STEMI [ Time Frame: 6 months ]
    An episode of neurological dysfunction caused by focal cerebral, spinal, or retinal infarction within the 6 months following a first STEMI, confirmed by clinically-indicated imaging technique (CT or MRI).
  • High Intensity Transient Signals (HITs) detected by transcranial Doppler monitoring of both middle cerebral arteries during 30 minutes within the 24-72 hours after STEMI [ Time Frame: 24-72 hours ]
  • Neuropsychiatric and cognitive impact of SBIs within the 6 months after STEMI assessed by Beck and Minimental questionnaire [ Time Frame: 6 months ]


Original Secondary Outcome: Same as current

Information By: Hospital General Universitario Gregorio Marañon

Dates:
Date Received: September 20, 2016
Date Started: September 2016
Date Completion: December 2020
Last Updated: October 3, 2016
Last Verified: October 2016