59Y Female with
Thermal Mapping in RCA Using Pressure Wire
# of Measurements
39 y male with
Thermal Mapping of LCX using Pressure Wire
1 126 251 376 501 626 751 876 1001 1126
# of Measurements
Temperature Mapping in LAD
No of Measurements
LAD:100% PROXIMAL OCCLUSION
LCA:70% MID STENOSIS
RCA:SMALL ,NON DOMINANT
RANGE OF TEMPERATURE
1 2 3 4 5 6 7 8 9 10
of Atherosclerotic Plaques and its Correlation with
•Morteza Naghavi MD,
•Reji John MD, Said Siadaty MD,
•Sameh Naguib MD, Roxana Grasu MD,
•KC Kurian MD, Mohammad Madjid MD,
•James T. Willerson MD, Ward Casscells
The University of Texas-HoustonTexas Heart Institute
pH HeterogeneitypH Heterogeneity
Temperature HeterogeneityTemperature Heterogeneity
pH Distribution in 48 Human Carotid Plaques
This histogram demonstrates distribution of pH measured in 858
points in 48 carotid plaques of 48 patients. A marked variation
ranging from 6.5 to 8.9 is seen.
pH in Lipid Rich Yellow Areas vs. Calcified areas
Areas with large lipid core exhibit higher temperature and lower pH
p < 0.01
Correlation of pH and Temperature in Human Carotid Plaques Varied by the Areas
We see a marked inverse correlation between temperature and pH of
plaques that varies by macroscopic characteristics of plaques.
p < 0.01
Fluorescence Single-Emission Imaging Microscopy
of a Predominantly Lipid Rich Plaque Shows
Significant Microscopic pH Heterogeneity Mostly
Catheter Tipped with a Side Looking Silvered Conical
0.5 mm Mirror
1.1. Temperature at the lumen of living carotid plaquesTemperature at the lumen of living carotid plaques
correlates with density of inflammatory cells, andcorrelates with density of inflammatory cells, and
inversely with cap thickness.inversely with cap thickness.
2.2. Differences of more than 0.3 C were seen in allDifferences of more than 0.3 C were seen in all
specimens but only a minority had differences of 2specimens but only a minority had differences of 2oo
C orC or
3.3. Large differences in temperatures were more oftenLarge differences in temperatures were more often
found in patients who were younger, symptomatic,found in patients who were younger, symptomatic,
female, and not taking aspirin.female, and not taking aspirin.
4.4. These temperature differences can be detectedThese temperature differences can be detected
by infrared cameras.by infrared cameras.
5.5. Compared to normal arteries, inflamed andCompared to normal arteries, inflamed and
lipid-rich plaques are acidic, while calcified andlipid-rich plaques are acidic, while calcified and
thrombosed plaques are alkaline.thrombosed plaques are alkaline.
6.6. Plaque pH correlates moderately and inverselyPlaque pH correlates moderately and inversely
with plaque temperature.with plaque temperature.
7.7. Stefanadis and colleagues have reported that hotStefanadis and colleagues have reported that hot
plaques confer higher risk; it will be important toplaques confer higher risk; it will be important to
determine whether plaque prognosis is best determineddetermine whether plaque prognosis is best determined
by T,by T, ∆∆T, pH,T, pH, ∆∆pH or a combination.pH or a combination.
8.8. Heating to 41Heating to 41oo
C decreases expression of pro-C decreases expression of pro-
inflammatory genes.inflammatory genes.
9.9. Heating to 42-43Heating to 42-43oo
C causes apoptosis, mainly ofC causes apoptosis, mainly of
10.10. Near-IR Spectroscopy can estimate plaqueNear-IR Spectroscopy can estimate plaque
protein/lipid ratios and may also provideprotein/lipid ratios and may also provide
inferences as to concentrations of plaque Hinferences as to concentrations of plaque H++
NO, glucose, ONO, glucose, O22 and oxidants.and oxidants.
11.11. IR and near IR may predict plaque behaviourIR and near IR may predict plaque behaviour
alone or in combination with ultrasound,alone or in combination with ultrasound,
angioscopy, magnetic resonance orangioscopy, magnetic resonance or