A WANDERING CROWN Rami Khouzam, MD

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A WANDERING CROWN
Rami Khouzam, MD
Case presentation
• 56 yo AAF with no significant PMHx
• 2-3 months h/o episodic substernal chest
pressure to L arm
• Usually related to activity. Resolves with
rest or SL NTG
• + DOE
• One episode at night woke her up
• Has been told in the past that her EKG
is normal and that the pain is d.t. anxiety
Medications:
• SL NTG (recently started)
• ASA & CaCO3
Family Hx:
• No h / o heart disease
• + for HTN, DM
Social Hx:
• Remote tobacco user
• Denies drugs
PE
• Neck: No JVD. No bruits
• CVS: RR, normal S1 & S2; +S4; no S3 , m
or r ; PMI non-displaced
• Lungs: CTA bilaterally
• Ext: No e, c, c
• Labs: Normal
• CXR: Normal
• EKG: NSR; flattened T’s in III, aVF and
V3-V6
EKG
Echocardiogram
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Normal chamber size & dimension
Normal LV Systolic fn. EF: 55-60%
Mild concentric LVH
Trace MR, Mild TR
Normal IVC
No pulmonary HTN
Cardiac catheterization
• L Main: Normal
• LAD: Normal
• L Cx: Normal
• RCA: Unsuccessful engagement. Aortic root
angiogram: probable anomalous origin from
left coronary cusp
Cath
ETT
• Exercise time: 7:06 min, Mets: 8.7
• Chest Pain
• 1 mm inferolateral ST depression
• Clinically & EKG’ly positive
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Anatomy of Normal Coronary Arteries
Anomalous origin of Coronary Arteries
Embryology
Pathophysiologic mechanisms
Clinical presentation
Diagnostic modalities
Treatment
Definitions of the word
“Corona”
in Webster’s Dictionary
Corona: (latin) A
crown or something
like a crown
In Anatomy
• “The Upper part of
tooth”
• “A Skull”
In Astronomy
“A circle of light
around the sun or
the moon; the halo
around the sun
during a total
eclipse”
In Botany
“The cuplike part
of the inner side
of the corolla of
certain flowers”
In Electricity
“A sometime
visible electric
discharge around a
conductor at high
potential”
In my fellowship
And the MOST famous Corona
of them all...
Number and size of coronary
ostia
• Normally an individual has 2 or sometimes
3 coronary ostia
• Conal branch of the RCA may arise
separately from the right sinus
• The Cx or LAD may, on occasion, arise
directly from the aortic root/ Absent Lt. Main
 Anomalous pulmonary origins of the
coronaries (APOC)
 Anomalous aortic origins of the coronaries
(AAOC)
 Congenital atresia of the left main
coronary artery (CALM)
 Coronary arteriovenous fistulae (CAVF)
 Coronary artery bridging (CB)
 Coronary artery aneurysm
 Coronary stenosis
Frequency
• In the US: Coronary arteries anomalies
are observed in:
– 0.3-1.3% of patients undergoing diagnostic
coronary angiography
– 1% of routine autopsy examinations
– in 4-15% of young people who experience
sudden death
Coronary Artery Anomalies
A review of more than 10,000 patients from
the Clayton Cardiovascular Labs
Charles Wilkins, et al. Texas Heart Institute
Journal 1988;15:166-73
Aanomalous Origin & Course…
Incidence
1- Cx from RCA or right sinus of Valsalva:
the most common: 0.48 %
2- Both coronary arteries from left sinus
of Valsalva: 0.28 %: reported in 1982 by
Roberts et al
3- Both coronary arteries from right sinus of
Valsalva: 0.06-0.19 %
4- Single coronary artery: 0.06 %
5- LAD from RCA or right sinus of Valsalva:
first reported in 1966 by Jokl et al.
Course is important
- Anterior to pulmonary trunk
- Posterior to aorta
- Within intraventricular septum
- Between aorta & pulmonary trunk
Development of the coronary
vessel system
Circ. Res. 2002;91:761-768
David E. Reese
Not everyone has coronary vessels
• Not all organisms with a heart have coronary
vessels
• Invertebrates DO NOT have coronaries (seastar,
jellyfish, worms…)
• Among the vertebrates: Most amphibians; newts,
salamanders and bullfrogs have no coronary
vessels
• In fish (the last vertebrate class), the
presence of coronary vessels is variable
• Larger fast-swimming fish have extensive
coronary vessels
• Most other vertebrates; mammals,
reptiles and avians have complete
coronary systems
• Dependance on pulmonic respiration
and the lack of cutaneous respiration
• Complete anatomical separation of left
(oxygenated) and right (deoxygenated) sides of
the heart 
– The use of circulating luminal blood to deliver oxygen
to the right ventricle is impossible
– Thick-walled ventricle that can’t be served by simple
gas diffusion from the myocardium to the heart lumen
• An alternative method of delivery, presumably
the coronary system was necessitated
Development of the coronary
vessels
• Complex vasculogenic process that
begins after heart looping
• Coronary vasculogenesis: regulated by
myocardium, but also dependent on
epicardium and its precursor, the
proepicardial organ, for the provision of
coronary vascular progenitor cells
Origin of Cells that make up the Heart
•
•
•
•
•
Cardiac myocytes
Endocardial endothelium
Fibroblasts
Vascular smooth muscle
Vascular endothelium
The Decision to make Arteries & Veins, Remodeling,
and Making the final connection to systemic circulation
• Several molecules play a role in the
diversification of vessels
• Further growth ; complex process of
angiogenesis, vascular remodeling, and
arterialization of specific branches gives
rise to the definitive coronary system
• The initial phases of coronary
vasculogenesis proceed in the absence
of blood flow  caliber governed by
forces other than blood flow
• The final connection to the Aorta
involves local apoptotic events that
eventually lead to the melding of
coronary endothelia with that of the
aorta (Unique)
• The origins of the coronary arteries to
the aorta and the connection of the
coronary sinus to the right atrium occur
in different regions of the heart
• How do these 2 vessel systems run
parallel on the surface of the heart but
diverge to make connections to the
systemic circulation?
• Considering the acrobatic nature of this
developmental system, it should not be
surprising that errors occur
Cellular precursors of the
coronary arteries
• EPDCs (Epicardial derived cells) might be
found to have a competence similar to that
shown by the recently discovered
bipotential vascular progenitors cells,
which are able to differentiate into
endothelium or smooth muscle depending
on their exposure to VEGF or PDGF-BB
Tex Heart Inst J. 2002; 29 (4): 243-249
• Vascular endothelial growth factor
(VEGF)
• Both VEGFR-2 and R-3 may play a role
in the formation of the coronary artery
roots
Tomanek RJ - Dev Dyn - 01-NOV-2002;225(3):233-40
Intimal preatherosclerosis
thickening of the coronary
arteries in human fetuses of
smoker mothers
J Thromb Haemost. 2003
Oct;1(10):2234-8
Matturri L
Preatherosclerotic intimal alterations of
the coronary arteries are already
detectable in the prenatal period and
are significantly associated with
maternal cigarette smoking
Anomalous Coronary Artery
from the opposite sinus:
Pathophysiologic Mechanisms
as documented by IVUS
The Journal of Invasive Cardiology,
Sept 2003
Paolo Angelini, et al.
1- Tangential origination with a proximal
intramural course  lateral compression of
the lumen  outward displacement of the
inner (more than the outer) layer of the
aortic wall.
Phasically accentuated during late systole
and early diastole.
On IVUS: intramural segment: area
reduction of 22 % to 69 %
• Young athletes  CO from 5
L/min at rest (HR 70, SV 71)
to ~ 25 L/min during exercise
(HR 200, SV 125)
 significantly  aortic wall
stress while expanding aortic
dimensions
• As the aorta and pulmonary artery
become larger with late childhood,
compression obstructs the blood flow in
this aberrant coronary
• The expected  in aortic compliance with
aging could contribute to ACAOS more
benign prognosis in older patients
2- Spasm of ostium and/or proximal ectopic
coronary artery (slit-like or hypoplastic ostium)
3- Clot formation
4- Aortopulmonary scissors effect:
Influence exerted entirely by aorta ? (pulmonary
a. pressure much lower than c.a pressure, &
less or not likely to cause coronary luminal
collapse)
5- Aortic hinge effect (acute angle of take-off)
• 68 % had associated CAD (> 50 %
luminal stenosis of 1 or more vs. )
• 19 % had cardiac abnormalities other
than CAD
Symptoms & Signs:
• Asymptomatic
• Symptoms in < 30 %:
- Palpitation
- DOE
- Angina ( in older patients)
- Syncope
- Fatigue
- Sudden death (in younger patients)
Imaging Studies
(non-invasive)
• Transthoracic echocardiography TTE
• Transesophageal echocardiography TEE
• Electron beam computed tomography EBCT
• Multidetector computer tomography MDCT
• Magnetic resonance imaging MRI
TEE
• Intermediate course between the aorta &
PA:
- Predominant systolic flow pattern
• Anomalous LM coursed anterior to the
pulmonary trunk:
- Predominant diastolic flow pattern
J Am Soc Echocardiogr 2003;16(12)
Visualization of coronary artery
anomalies and their anatomic
course by contrast-enhanced
electron beam tomography and
three-dimensional reconstruction
The American Journal of Cardiology
(Volume 87. Number 2. Jan.15, 2001)
Dieter Ropers, MD
Germany
EBCT
• Very high temporal resolution
• No mechanical parts are involved in image
acquisition
• Instead, X-ray are created by an electron
beam, which sweeps across fixed
tungesten targets arranged in a
semicircular manner around the patient
Dieter Ropers,Germany Am J Cardiology 2001;87(2)
• One high resolution image acquired in
50 to 100 ms
• Slice thickness is 1.5 or 3.0 mm,
(triggered by the EKG images acquired
up to 5 times within one cardiac cycle) 7
to 9 line pairs per cm
MDCT
• X-ray gantry rotation time of 500 ms or less
• Images free of motion artifact
• Stimultaneous data acquisition in 16 parallel
cross-sections with collimations of less than
1 mm
• 9 line pairs per cm
• Sensitivity of EBCT: 74% - 92% with
specificities 66% - 94%
• Sensitivity of MDCT: 72% - 95% with
specificities 84% - 97%
• Slow heart rate is a prerequisite 60 - 65
• ß-receptor-blocking
• Definitive diagnosis: selective arterial
angiography
• (Swan-Ganz) catheter to guide
assessment of the course of the
anomalous vessels is recommended
Treatment
Surgery is the only definitive treatment
of coronary artery anomalies
• The surgical techniques evolved over the
last 5 decades
• 178 patients, Texas Heart Institute from
December 1963 through June 2001
• 15 patients underwent surgery for AAOC
A ) RCA from the left sinus of Valsalva
• Reimplantatoin of the anomalous
coronary artery to the ipsilateral sinus of
Valsalva
• Ligation of the anomalous artery and
bypass with a saphenous vein graft
• (RIMA) without ligation of the RCA
2 ) LCA or circumflex branch originated from the
right sinus of Valsalva
• Bypass grafting with anastomosis od the LIMA
to the LAD artery
• RIMA graft to the circumflex branch
• Saphenous vein graft to the circumflex branch
• No deaths, follow-up coronary angiography
showed no graft failure
• Surgical indications for AAOC are more
controversial
• Some authors advocate the use of
internal mammary arteries because of
their long-term patency advantage over
vein grafts
• Others advocate the use of vein grafts
to avoid the early occlusion and
stenosis that can occur in arterial grafts
that are used to bypass vessels with
competetive flow
• Another difficult decision whether to
ligate a patent anomalous artery in
order to eliminate competitive flow
• Many efforts have been made to noninvasively image the coronary arteries
using magnetic resonance, electron
beam computed tomography, and
recently multidetector computed
tomography (MDCT)
• A new generation of MDCT scanners
with arrays of detectors, a higher
temporal an spatial resolution
Monarchies of the World
• There are ~ 225
inhabited countries
and territories in the
world
• 47 countries (~ < 1/4)
are monarchies
Moral of the Story
Well-deserved Royalty:
Not just to have a
crown….but to have a
well-fitting ONE!
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