Effect of Distal Embolisation on

1
Effect of Distal Embolisation on Myocardial
Perfusion Reserve Following Percutaneous Coronary
Intervention A Quantitative MR Perfusion Study
Selvanayagam JB MBBS, DPhil Cheng ASH MBBS
Jerosch-Herold M PhD Rahimi K MDPorto I MD
Neubauer S MD Banning AP MD
From the University of Oxford Centre for Clinical
Magnetic Resonance Research, University of
Oxford, UK Department of Cardiovascular
Medicine, Flinders Medical Centre, Adelaide,
Australia and Advanced Imaging Research Center,
Oregon Health Science University, Portland, OR,
USA
2
Background

• Studies using intra-coronary Doppler have shown
  that a proportion of patients demonstrate
  persistent impairment in microcirculatory
  function after PCI,
• even after substantial conduit area enlargement
• using high resolution quantitative CMR, we sought
  to investigate this by evaluating PCI-induced
  changes in myocardial perfusion reserve index
  (MPRI) and procedure-related myonecrosis
• HYPOTHESES
• MPRI is impaired in segments with new distal
  PCI-induced injury
• myocardial segments upstream to the injury in
  the territory of the culprit vessel would not
  demonstrate persistent microvascular dysfunction
  after PCI

3
Methods
4
Results
5
Results
3
5
.
2
2
Mean MPRI Score (95 CI)
6 months FU
Pre PCI
24h Post PCI
Control
Distal HE
Upstream
6
Table 1
Results


MPRI



No of
z
-
Pre
-
PCI
24h post
-
PCI
Change after 24h
value
p
-
value

segments






1. Affected segments in all 40 patients






2.06
2.52
0.46
No HE

322

(1.99, 2.13)

(2.42, 2.62)

(0.36, 0.56)

-
4.82

lt0.001

HE (distal)

82

2.16
(1.95, 2.37)

2.00
(1.82, 2.1
9)

-
0.16
(
-
0.29,
-
0.02)


2. Affected segments in 21 patients with distal
new injury

No HE

170

2.18
(2.07, 2.30)

2.35
(2.22, 2.47)

0.17
(0.04, 0.29)

-
6.85

lt0.001

HE (distal)

82

2.16
(1.95, 2.37)

2.00
(1.82, 2.19)

-
0.16
(
-
0.29,
-
0.02)


3. All seg
ments in 21 patients with distal new injury

Upstream (reference group)

141

2.18
(2.05, 2.30)

2.31
(2.17, 2.44)

0.13
(0.03, 0.23)

-

-

2.22
2.05
-
0.17
Distal

70

(1.98, 2.45)

(1.84, 2.26)

(
-
0.32,
-
0.02)

-
4.88

lt0.001

Remote

90

2.22
(2.08, 2.37)

2.43
(2.2
5, 2.60)

0.20
(0.02, 0.39)

0.68

0.50

No PCI

146

2.24
(2.08, 2.39)

2.42
(2.31, 2.54)

0.19
(0.04, 0.33)

0.70

0.48









HE denotes hyperenhancement, MPRI myocardial
perfusion reserve index, PCI percutaneous
coronary intervention. Upstreammyocardial
segments supplied by the culprit vessel proximal
to the distal HE Remotesegments that underwent
PCI in a second vessel in the same patients but
not displaying new injury distal HEsegments
demonstrating new distal injury No PCISegments
that are subtended by arteries that did not
undergo PCI
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Table 2
Results
Rest MBF (ml/min/g)
Stress MBF (ml/min/g)
P value
Pre PCI (HE negative)
2.2 (2.0, 2.4)
1.0 (0.9, 1.1)
1.0 (0.9, 1.1)
Pre PCI (HE positive)
2.2 (1.9, 2.5)
0.01
1.0 (0.9, 1.1)
2.8 (2.3, 3.3)
Early Post PCI (HE negative)
1.9 (1.7, 2.1)
0.03
Early post PCI (HE positive)
1.0 (0.9, 1.2)
2.7 (2.3, 3.0)
Late post PCI (HE negative)
0.8
1.1 (0.9, 1.3)
0.03
Late Post PCI (HE positive)
1.2 (0.9, 1.4)
2.8 (2.3, 3.3)
HE denotes hyperenhancement, MBF myocardial blood
flow, PCI percutaneous coronary intervention.
when compared with pre-PCI value, when
compared with 24 hour post-PCI value
8
Results
Remote segments in the same patients subtended
by a vessel that was intervened upon and which
had no new HE Upstream segments supplied by
the culprit vessel, proximal to the distal HE
Distal HE segments demonstrating new distal
HE
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Conclusions

• MPRI is reduced in segments demonstrating new
  distal irreversible injury at 24 hours after
  PCI
• These reductions are transient and confined to
  the segments with injury
• Microcirculatory impairment early after PCI may
  be due to both new myonecrosis and transitory
  macro/microvascular plugging of the vascular bed