Purpose
The purpose of this study was to measure left ventricular myocardial perfusion quantitatively (in ml/100g/min) in patients with clinical indication for coronary dilatation/stenting,
coronary bypass surgery or aortic valve replacement before and after therapeutic procedures to determine alterations in myocardial perfusion (primary outcome measure).
The secondary outcome measure was the assessment and correlation analysis of physiological parameters possibly influencing myocardial perfusion such as heart rate (HR),
systolic blood pressure (SBP) and rate pressure product (RPP) and the examination of ventricular parameters that may show an...
Methods and Materials
The study was prospectively conducted to evaluate myocardial blood flow (MBF) before and after surgery in patients with indication for coronary dilatation/stenting,
coronary bypass surgery or aortic valve replacement.
CT-Examinations
All CT studies were performed with ECG-gating triggered at 40 % of the R-R-interval,
i.
v.
contrast agent with a concentration of 210 mgIodine/ml and 80,
100 or 120 KV (Rienmüller et al.
2013) depending on the patient’s weight using a 256 row volume CT.
The images were acquired every heart beat and reconstructed with...
Results
12 patients have been included in the study so far: 4 with indication for aortic valve replacement and 8 with indication for coronary bypass surgery.
There were no patients undergoing coronary dilatation/stenting.
Physiological Parameters
The measured physiological parameters of the patients are listed in Tab.
1 (mean±SD (range)).
We could observe an increase in heart rate (HR,
see Fig.
3) and rate pressure product (RPP,
see Fig.
5),
and a non statistically significant decrease in systolic/diastolic blood pressure (SBP/DBP,
see Fig.
4) comparing before and...
Conclusion
Our preliminary results demonstrate that we can approve the general feasibility of quantitatively measuring myocardial blood flow (MBF) on a routine basis.
We could show a statistically significant increase in MBF in both patient groups together (aortic valve replacement and coronary bypass,
n=12) after surgical treatment of the patient (primary outcome).
Part of this increase may be attributable to a significant increase of the patients' heart rate.
As known from physiology,
the rate pressure product (RPP) is a good indicator for the oxygen consumption of...
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