VASCULAR AND INTERVENTIONAL

ANKLE BRACHIAL INDEX:

ABI 1.0 normal
0.6-0.9 exercise claudication
< or = 0.5 rest pain 
< 0.3 tissue loss

AXILLARY ARTERY BRANCHES:

SALSAP (superior thoracic, acromiothoracic, lateral thoracic, subscapular, anterior circumflex humeral, posterior circumflex humeral). The thoracodorsal and circumflex scapular are branches of the subscapular.

The axillary artery originates at the level of the clavicle proximal to the pectoralis minor muscle. The first branch of the axillary artery is the superior thoracic artery, next is the thoracoacromial artery which arises under the pectoralis minor muscle. The lateral thoracic artery is the next branch, in the axilla the subscapular artery is the next branch that gives off the circumflex scapular and the thoracodorsal artery. The circumflex humeral is the last branch of the axillary artery.

ANGIO OF ILIAC AND FEMORALS:

best projection for iliac is ipsilateral oblique and for femorals is contralateral oblique

REVIEW OF ARTERIAL ANATOMY IN AP PROJECTION:

CONCERNING BRONCHIAL ARTERY EMBOLIZATION:

The embolic agents chosen for bronchial artery embolization reflect the site of desired arterial occlusion. Absolute alcohol, boiling contrast or particulate powders produce occlusion at the level of the smallest vessels and accomplish tissue necrosis. This is to be avoided in bronchial artery embolization because of the risk of bronchial or esophageal infarction or spinal cord damage. Coils produce focal arterial occlusion at the large vessel level and invite peripheral collateralization and are therefore also inappropriate for bronchial artery embolization.

Particulate emboli such as polyvinyl alcohol particles or Gelfoam in the 350 to 500 m size range are most appropriate for bronchial artery embolization. These agents will provide hemostasis without tissue necrosis. Particles of this size will likely be too large to enter small spinal radicular branches. Polyvinyl alcohol particles provide more long-term occlusion than Gelfoam particles which will be at least partially resorbed in 30 days. (ref: direct quote from: http://rwj-rad.rwjuh.edu/newcases.d/bron.html)

ANATOMY OF THE BRONCHIAL ARTERIES (They originate most commonly from the proximal descending thoracic aorta anterolaterally between the level of the fourth and sixth thoracic vertebral bodies. In terms of their appearance, there are frequently multiple left and right bronchial arteries arising from the aorta, and often there is a common trunk from the anterior aspect of the thoracic aorta giving rise to both right and left branches). Single individual left and right  bronhial arteries are the most common (30%). The next most common appearance (25%) is a common trunk giving rise to both right and left together with a single right (which results in 2 on the right and one on the left):

COMPARISON OF ANGIOPLASTY WITH SURGERY FOR FEM POP DISEASE

Claudicants have 3 year patency 60%, patients with critical ischemia have 3 year patency of 40%. Restenosis secondary to intimal hyperplasia occurs months (early) after PTA, progression of arteriosclerotic disease is important cause of stenosis > 9 months. Most clinical failures are reported < one year. Surgery and PTA have shown to have identical results for patients with chronic limb ischemia for patients who are candidates for either. Surgery, however, is more effective in treating patients with long segment, diffuse stenosis or occlusions involving the origin of the SFA or distal popliteal artery or the trifurcation.

ACUTE COMPARTMENT SYNDROME:

pressure in the compartment should not be > than 30mm. If you have normal blood pressure, than 40-45 mm is diagnostic.

CONTRAINDICATIONS TO ENZYMATIC FIBRINOLYSIS:

recent intracranial, thoracic or abdominal surgery

recent GI bleeding

recent stroke or intracranial neoplasm

recent major trauma

pregnancy

severe htn

bleeding diathesis

infected thrombus

ANOMALIES OF THE MESENTERIC ARTERIES:

COLLATERAL CIRCULATION:

VENOUS COLLATERALS (there are quite a few of these):

occlude suprarenal IVC: common iliac go to lumbars go to azygous go to SVC

occlude SVC near junction with RA: azygous go to lumbar go to IVC

occlude PV: SMV go to splenic v go to IMV go to hemorroidal go to internal iliac go to common iliac go to IVC

TRAUMATIC AORTIC RUPTURE:

#1: isthmus (88-90%)

#2: avulsion of arch just proximal to takeoff of brachiocepalic trunk (4-5%)

#3: at diaphragmatic hiatus (1.8%)

the pretest book (Hovespin) says that the most common place for traumatic aortic rupture is the isthmus and aortic root

SOME CEREBRAL ANGIOGRAPHY

note: ICA angio requires 6cc/s for 8 cc total volume

ECA angio requires 3cc/s for 8 cc total

here is the ap and lateral projections of internal carotid artery injections (taken from http://user.shikoku.ne.jp/tobrains/exam/Angio/Angio-e.html):

you can can check out the dynamic angios by clicking on the above link

these 2 images represent ap and lateral projections of vertebral artery injections (taken from: http://user.shikoku.ne.jp/tobrains/exam/Angio/Angio-e.html). You can ckeck out the angios by clicking on the link:

H. Posterior Cerebral Artery I. Superior Cerebellar Artery J. Basilar Artery K. Antero-inferior Cerebellar Artery L. Postero-inferior Cerebellar Artery M. Vertebral Artery

MORE CEREBRAL ANATOMY (quoted from http://www.meddean.luc.edu/lumen/MedEd/Neuro/neurovasc/navigation/nvhome.htm):

ANTERIOR CEREBRAL TERRITORY:

the Heubner originates from the A1 one quarter and the A2 three quarters of the time. It is one of the important medial lenticulostriate branches. Note that the A1 supplies the medial lenticulostriates and the A2 supplies the recurrent artery of Heubner most of the time. Note also that the MCA supplies the lateral lenticulostriates

The anterior cerebral artery supplies most of the medial surface of the cerebral cortex (anterior three fourths), frontal pole (via cortical branches), and anterior portions of the corpus callosum.

Perforating branches (including the recurrent artery of Heubner and Medial Lenticulostriate Arteries) supply the anterior limb of the internal capsule, the inferior portions of head of the caudate and anterior globus pallidus.

Bilateral occlusion of Anterior Cerebral Arteries at their stems results in infarction of the anteromedial surface of the cerebral hemispheres:

Paraplegia affecting lower extremities and sparing face/hands.

Incontinence

Abulic and motor aphasia

Frontal lobe Symptoms: personality change, contralateral grasp reflex.

Unilateral occlusion (distal to Ant. Comm. origin) of Anterior Cerebral Artery produces contralateral sensorimotor deficits mainly involving the lower extremity with sparing of face and hands (think of the humunculus).

MCA TERRRITORY:

The MCA supplies most of the temporal lobe, anterolateral frontal lobe, and parietal lobe.

Unilateral occlusion of Middle Cerebral Arteries at the stem (proximal M1 segment) results in: Contralateral hemiplegia affecting face, arm, and leg (lesser). Homonymous hemianopia - Ipsilateral head/eye deviation. If on left: global aphasia. Usually occlusion is embolic in nature - thrombotic occlusion more common in carotids.

BASILAR ARTERY BRANCHES:

INTERNAL CAROTID ARTERY TERRITORY:

LATERAL INTERNAL CAROTID  (http://www.t2star.com/angio/Neuro2.htm):

1. Cervical ICA 2. Meningohypophyseal Trunk 3. Lateral Mainstem Artery 4. Opthalmic artery 5. PCOM ( Posterior Communicating Artery) 6. PCA (Posterior Cerebral Artery)

ICA OCCLUSION:

in a pt with complete proximal ica occlusion, distal ica perfusion can occur via retrograde flow in the ipsilateral ophthalmic artery.

SUPRACLINOID CAROTID BRANCHES:

the pnemonic for supraclinoid carotid segments is OPA (ophthalmic, posterior communicating and anterior choroidal)

CAROTID BASILAR ANASTOMOSES:

Note that the carotid basilar pathway is through carotid-basilar anastomoses which develop during fetal life between the internal carotid and basilar arterial systems for the supply of the posterior cranial circulation. These include the trigeminal, hypoglossal, otic and pro-atlantal segmental arteries. With the development of the posterior communicating artery, these channels get obliterated but may rarely persist into adult life. The persistent trigeminal artery is the most common anomaly among the four, followed by the hypoglossal artery

MORE ON CAROTID-BASILAR ANASTAMOSES:

persistent primitive trigeminal>primitive hypoglossal>persistant otic, proatlantal intersegmental artery

FRONTAL INTERNAL CAROTID (http://www.t2star.com/angio/Neuro2.htm):

1. Internal Carotid. 2. Middle Cerebral Artery. 3. Horizontal (A1) segment of the (ACA). 4. Anterior Communicating Artery (ACOM). 5. Small ACOM branch to Basal ganglia, Corpus Callosum. 6. Medial Lenticulostriate Arteries. 7. Recurrent Artery Hebner. 8. A2 segment of ACA. 9. ACA Bifurcation. 10. Pericallosal Artery. 11. Calloosalmarginal Artery (ie at the marrgin of the brain)

TERRITORY OF THE ECA (http://www.t2star.com/angio/Neuro2.htm) (ASLEOPS):

LATERAL PROJECTION OF ICA AND ITS BRANCHES (http://www.t2star.com/angio/Neuro2.htm):

1. External carotid artery. 2. Occipital artery.  3. Superficial temporal artery. 4. Maxillary artery.  5. Middle meningeal artery. 6. Ascending pharyngeal artery. 7. Vidian artery.  8. Artery of foramen rotundum. 9. Infraorbital artery.  10. Descending palatine artery. 11. Buccal artery

STENTING FOR BENIGN AND MALIGNANT BILIARY STRICTURES:

Various types of biliary stents are commercially available. The plastic stents have two major problems: migration and occlusion. The metallic stents come in either balloon-expandable (ie, Palmaz stent, Strecker stent), or self-expanding types (ie, Wallstent, Gianturco stent). Metallic stents can be introduced in a contracted state through a small caliber tract. The gianturco stent is better for benign biliary strictures as tumor can grow in between the wires resulting in stent occlusion. Note that restenosis occurs in 20-30% of benign biliary strictures and requires re-ballooning

This is what Valjii has to say on stents: 

They can be self expanding or balloon expandable

the palmaz is a balloon expandable stent made of stainless steel. it shortens slightly as the balloon inflates. the device has minimal elastic deformation and has some longtidudinal flexibility and permanent plastic deformation. It should not be placed where intrinsic force could crush the stent

the wallstent (Boston Scientific) is a flexible self-expanding stent composed of stainless steel filaments woven in a cross hatched pattern. It is available in a variety of fully deployed lengths and diameters. Its expanded length is considerably shorter than its compressed length. Placement is less precise than with other devices. It has almost no plastic deformity but considerable elastic deformity and longitudinal flexibility. These properties make it easy to pass through tortuous vessels and tight curves.

the strecker stent i(Denmark) is made of tantalum monofilament woven into a mesh. the stent is deployed from a specially fashioned balloon and is very flexible and elastic.

the Gianturco Rosch Z stent (Bloomington IN) is made of stainless steel wire in a zig zag pattern. It is self expanding and quite elastic. the Z stent is used primarily for esophageal strictures and long central venous stenoses.

HOW TO GO FROM THE IVC TO THE AORTA WITHOUT PASSING TROUGH THE LEFT VENTRICLE:

first of all this question keeps on showing up on those dreaded boards: this is the official list: truncus arteriosus, tetralogy of Fallot, transposition, hypoplastic left heart, DORV. In hypoplastic L heart, the catheter has to pass through a patent PDA, which is  necessary to maintain life. 

EFFECT OF PULMONARY CAPILLARY WEDGE PRESSURE ON APPEARANCE OF THE LUNGS:

PCWP: 8-12 normal
12-18 redistribution
19-25 interstitial pulmonary edema
> 25 alveolar flooding

CONTRAINDICATION TO PULM ARTERIOGRAPHY:

main one is pulm htn as this can lead to sudden death. a relative one is LBBB as manipulation of a catheter in the RV can cause RBBB leading to total heart block!

DRUGS IN VASCULAR IMAGING:

vasodilators:

papaverine: mesenteric ischemia. sm muscle relaxant, long acting

tolazoline: peripheral spasm, direct sm muscle relaxant

ntg: peripheral spasm, direct sm muscle relaxant, short acting

nifedipine: peripheral spasm, for htn

vasoconstrictors:

vasopressin, used for GIB, contraindicated in CAD, HTN, arrthymia

epinephrine: renal vasoconstriction, used to differentiate tumor vessels from NL vessels

PTA SUCCESS RATES:

iliac: 95% initial, 70-80% 5 year

femoral: 90% initial, 70% five year

renal: 95% initial, 70-90% five year

CYSTIC MEDIAL NECROSIS:

tulip bulb appearance due to cystic medial necrosis. The causes are htn, marfans, ehlers danlos. There is involvement of the aortic sinuses and sinotubular junction which causes AI. Dissection is a frequent complication and Ca++ is rare. 

SYPHILITIC ANEURYSM:

In contrast to the above, syphilitic aneurysm has a tree bark appearance. Ca++ is common and dissection is rare

AORTIC GRAFT COMPLICATIONS:

Endovascular stent grafting is an alternative to surgical repair. Generally, aneurysms will decrease in size following successful endograft repair. Complications of endovascular stent graft include:

1- Endoleak (peri-implant leakage into the aneurysm) is the most common complication. Leak can occur in up to 45% of patients (8% to 45%) and is is more consistently identified by helical CT than conventional angiography . The leak most commonly occurs at the proximal or distal end of the stent due to incomplete fixation to the aortic wall. Retrograde flow via patent arteries can result in mid-graft endoleaks. There are 4 types of endoleaks:

Type 1 occurs at the graft insertion site due to an inadequate seal between the stent graft and the aortic wall. These leaks result in elevated sac pressure and a continued risk for rupture.

Type 2 occurs when there is retrograde inflow in a patent branch vessel. Retrograde endoleaks are unavoidable with current endovascular techniques. The risk for type 2 endoleak is increased with increasing patent side branch vessels. The clinical importance of Type 2 endoleaks is not clear. Small leaks can be associated with a stable sac size and can spontaneously resolve. However, this type of leak (even small leaks) is often associated with failure of the aneurysm to decrease in size and it may actually increase.

Type 3 occur due to graft degeneration including component disconnection, fabric tears, and disintigrationl

Type 4 leaks occur due to transgraft flow due to graft wall porosity

There is another type of leak referred to as "endotension"- no leak is visible radiographically, but the aneurysm continues to grow. Scanning the graft in both the arterial and delayed phases is important. About 18% of leaks will only be seen on arterial phase images, while about 3% will only be seen on delayed exams. Note that gas may be seen in the aneurysm sac immediately following stent deployment and should not be considered pathologic when scans are performed at that time.

2- Graft thrombosis: Partial, peripheral, semicirular thrombosis is seen in 3-19% of stents. Graft occlusion is rare.

3- Graft kinking: Kinking occurs when large aneurysms shrink/shorten after stent grafting. The kinking may not be detected on transaxial images, but can be demonstrated on MIP or MPR images.

4- Shower embolism: Shower embolism occurs in 4-17% of cases and is generally fatal.

5- Colonic necrosis (abdominal aortic stent grafting)

6- Aortic dissection

7- Vascular perforation

8- Pseudoaneurysm associated with graft infection

ANATOMY OF ILIAC ARTERY AND FEMORAL ARTERY RELATIVE TO THE INGUINAL LIGAMENT:

Schematic of Common femoarl artery from Gray;'s anatomy

Another schematic showing the relation to the inguinal ligament (also from Gray's)

Anatomy of the inguinal ligament and relation of the great vessels to it. Quoted from wheelers online (http://www.wheelessonline.com/05/300.htm):

Anatomy: - common iliac bifurcates at the L5-S1 disc; - external iliac artery passes obliquely down medial border of psoas & anterior and lateral to external iliac vein; - external iliac artery becomes the common femoral artery as it passes below the inguinal ligament; - common femoral artery is approximately 4 cm in length and divides into superficial femoral & profunda femoris arteries; - in upper thigh, this artery lies between femoral vein & nerve in femoral triangle, space roofed by fascia lata and bounded by inguinal ligament above, satorius muscle laterally, & adductor longus medially; - largest branch of the femoral artery in femoral triangle is profunda femoris, which arises on lateral side of the femoral artery, arches posteriorly, and continues downward near the middle of the thigh; - descending genicular artery arises from femoral artery; - at the distal apex of the femoral triangle, above the knee, it passes thru opening in adductor magnus to enter popliteal space as popliteal artery; - after providing genicular arteries at level of knee joint, it passes deep to soleus, where it transverses thru another fibrous tunnel; (hence, artery remains vulnerable during dislocation of knee because of tethering); - popliteal artery then sends paired sural arteries to gastrocnemius & soleus & ends by dividing into anterior & posterior tibial arteries;