- To compare relative myocardial mass distribution (i.e. mass of the respective territories of LAD, LCX and RCA) by CT scanning to normalized hyperemic blood flow in the three major myocardial territories as assessed by absolute flow measurements…
ID
Source
Brief title
Condition
- Coronary artery disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Het is rondom coronaire interventies zoals PCI of CABG van klinisch belang om
het risico voor de patient in te schatten. Er is tot op heden geen
non-invasieve methode beschikbaar om het gebied van necrose in te schatten na
een myocardinfarct of procedure. Vooral bij een percutane coronaire interventie
(PCI) zou het erg waardevol zijn om informatie te hebben omtrend de absolute en
relatieve myocardiale massa distaal van het 'interventie gebied'. Deze
informatie kan helpen bij de risico inschatting en tevens bij het bepalen van
de beste revascularisatie methode bij meervatslijden. Het primaire
onderzoeksdoel is dan ook het quantificeren van de hartmassa en bloedflow per
coronairgebied.
Secondary outcome
not applicable
Background summary
Although knowledge about the myocardial mass (in grams) of the different
territories belonging to the major coronary arteries, is of clinical importance
to estimate risk of coronary interventions (PCI, CABG) and to determine area of
necrosis after myocardial infarction, no invasive methodology has been
available so far for reliable assessment of mass. Especially in the setting of
percutaneous coronary intervention (PCI), it would be valuable to have
information about the absolute and relative myocardial mass distal to the
location where the intervention is planned. Such information is valuable for
risk estimation and can also be helpful in multivessel disease to determine the
most adequate way of revascularization. Both MRI and CT scanning have claimed
to be able to estimate myocardial mass non-invasively, but by the lack of any
gold standard, none of these methods could be validated in vivo so far. A
relatively new development in CT technology is the calculation of fractional
flow reserve (FFR) by CT scanning, according to a sophisticated algorithm
developed by Heartflow Inc. One of the baseline assumptions in that algorithm
is that myocardial mass is proportional to resting blood flow, which seems a
plausible assumption from a rational physiological point of view. More
recently, invasive calculation of absolute blood flow has become possible as
well as resistance measurement of the (microcirculation of the) myocardium.
Using that invasive technology (explained in the appendix to this protocol), it
can be assumed that measuring absolute maximum blood flow in a coronary artery
as well as fractional flow reserve for different territories or for different
spots within one major coronary artery, provides a basis for relative mass
calculation. The background for performing the present study is to compare
these mass calculations by CT scanning and by invasive measurements, thereby
corroborating both methods.
Study objective
- To compare relative myocardial mass distribution (i.e. mass of the respective
territories of LAD, LCX and RCA) by CT scanning to normalized hyperemic blood
flow in the three major myocardial territories as assessed by absolute flow
measurements and FFR in patients with an indication for multivessel FFR
measurement.
- To compare relative myocardial mass belonging to a proximal or a mid segment
of one of the major coronary arteries measured by CT scanning to invasive
absolute flow and FFR measurement in that particular proximal or mid coronary
artery in patients undergoing single or multivessel PCI.
Study design
Because from a scientific point of view, no reason is present to set-up this
mechanistic study as a merely prospective study, also the *retrospective arm*
is included. This saves money, time, and unnecessary exams in prospective
patients.
Consequently, connected with this study protocol there is a regular informed
consent form (for the *prospective* patients) as well as a *simple* informed
consent form for anonymous use of data only (for the retrospective patients).
Study burden and risks
As the invasive procedure is not fundamentally different from a routine
procedure with FFR/physiologic measurements, and the procedure is prolonged by
20-30 minutes at the average only, the risk of the procedure compared to a
regular procedure is neglectable.
There is no direct benefit for the patient but the absolute flow measurements
provide an index of the microcirculation of the heart which might contribute to
a better understanding of his/her disease.
As for the coronary CT, the radiation exposure is equivalent to 3 mSv. For
comparison, radiation exposure due to the invasive procedure is generally in
the range between 10-15 mSv. For reasons of radiation safety, preferably
patients will be included in whom a coronary CT scan has already been made or
is indicated for clinical reasons, as is increasingly common in these patients.
In patients in whom no coronary CT is available, permission will be asked to
perform such CT scan as yet. Except for contrast allergy and decreased kidney
function, both exclusion criteria for this study, no direct risks are
associated with the CT scan performance.
Michelangelolaan 2
Eindhoven 5623EJ
NL
Michelangelolaan 2
Eindhoven 5623EJ
NL
Listed location countries
Age
Inclusion criteria
1) Presence of multivessel coronary disease with an indication for multivessel FFR and/or PCI
or Patients with single vessel disease scheduled for FFR/PCI of that single coronary artery
2) Availability of a coronary CT scan performed prior to the scheduled invasive investigation. The time difference between the CT scan and the invasive exam should be less than 3 months.
3) Focal lesions only
4) Normal left ventricular function
5) Age < 75 years
Exclusion criteria
1) Inability to give informed consent
2) Diffuse coronary disease
3) Tortuous or calcified arteries interfering with reliable invasive FFR assessment
4) Previous myocardial infarction or ejection fraction less than 60% by echocardiography or ventriculography or less than 50% by nuclear methods
5) Atrial fibrillation interfering with high quality coronary CT scanning
6) Age > 75 years
7) Other contra-indications for CT scanning
8) Pregnancy or admired pregnancy in the future
9) Left main stenosis
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL62884.100.17 |