Angiogram technique

Question 1

Complications of ventriculography

Answer 1

Arrhythmias
* Caused by mechanical stimulation of ventricular myocardium by KT/contrast jet
* Eliminated/minimized by replacing KT
* Rarely, can be sustained after removal of KT → treated w IV lidocaine bolus

Intramyocardial injections
* Deposition of contrast material w/I endocardium/myocardium
o Small stain usually benign
o Large stain → can lead to refractory ventricular arrhythmias (Vtach/fib)

Ventricular perforation
* Leakage of blood/contrast in pericardial space → cardiac tamponade
o Emergency pericardiocentesis
o Cardiothoracic surgeon

Fascicular block
* Transient L anterior fascicular block can occur during retrograde LV KT
o Proximity of anterior fascicle to LVOT
o Usually resolve in 12-24h

Embolism
* Injection of air or thrombus
* Minimized by frequent flushing w heparinized solution

Question 2

What causes intramyocardial injections

Answer 2

improper positioning of KT
o Under papillary muscle
o Side hole lies firmly against ventricular wall

Question 3

How to avoid endocardial staining

Answer 3

o Use KT with side holes + closed/tightly curved tip (NIH, Berma, Lehman’s, Pigtail)
 Allows for
* Better contrast dispersion
* Stabilization of KT tip
* Lack of recoil
o Avoid positioning under papillary muscle
o Avoid pressing against myocardium

Question 4

Appropriate settings for pressure injection during ventriculography

Answer 4

• Set to deliver a preset contrast volume over a brief period
• High pressure for small diameter KT
• Avoid air
• Settings
  o Flow rate 10-15ml/s
  o Total volume 20-50ml
  o Pressure limit 900-1200psi: 6Fr = 900psi, 4Fr = 1200psi
  o Rise time 0.2-0.5s

Question 5

Time for contrast injection determined by

Answer 5

KT type, size, flow rate, distance, volume, pressure

Question 6

Best injection site

Answer 6

injection of contrast directly into ventricular chamber
o LV: optimal position is mid cavity
 Adequate delivery of contrast material in chamber’s body/apex
 No interference w MV function
 Position of end hole away from ventricular trabeculae

o R heart:
 Usually pigtails or balloon tipped
* Straighten pigtails w guidewire before removal since can stay trapped in trabeculae
* Balloon: assisted by blood flow into RA → TV → RV → PA
o Deflate before removal

Question 7

What to do if ventricular ectopy during injection

Answer 7

reposition KT in ventricular inflow tract → in front of MV posterior leaflet

Question 8

What to do if vigorous ventricular contraction

Answer 8

no stable position found
o Can use pigtail → advanced to be in continuous contact w apex

Question 9

Injection rate and volume depends on

Answer 9

o Type and size of KT
o Size of ventricular chamber
o Ventricular SV
o Pre ventriculography hemodynamics
 If filling pressures are ↑ → LV ventriculography should be performed after nitroprusside

Question 10

Time for contrast injection depend on

Answer 10

o Length/radius of KT
o Pressure used to inject
o Rate of contrast injection

Question 11

Most common volume for contrast and preferred method of delivery

Answer 11

• Most cases: 1ml/kg
  o Side holes: 10-12ml/s
  o End hole: <7-10ml/s to ↓ recoil/staining
• Power injector: rapid delivery of adequate amount of contrast
  o Max pressure roughly 1000psi to avoid KT burst

Question 12

Contrast agents

Answer 12

• Iodine based
  o High atomic weight (↑radiodensity) → degree of opacity α to total amount of iodine in image
  o 1st generation: Salts of triiodinated benzoic acid
   High osmolality: 5-8x blood
  o 2nd generation: Non ionic monomers
   No dissolution in solution → less adverse rx
   Low osmolar agents: 2-3x blood
  o 3rd generation: Iodixanol
   Iso-osmolar dimer → not dissociate in solution
   Same osmolality of blood

Question 13

What property of contrast agent affects flow rate

Answer 13

Viscosity
o Warming contrast ↓ viscosity

Question 14

How does one distinguish significant TR from that caused by technical issues related to contrast injection during right ventriculography?

Answer 14

• RV angiography
  o Artificial TR from KT across TV: mild
   Small amount
   Clearance between beats

Question 15

Scale to classify TR severity

Answer 15

• Scale of +1 to +4 similar to MR assessment
  o +1 mild: clears in 1 beat, do not opacify entire RA
  o +2 moderate: not clear in 1 beat, faintly opacify entire RA
  o +3 moderately severe: RA completely opacified, equal opacification as RV
  o +4 severe: opacification become more dense after several beats, reflux in VC

Question 16

Causes of TR

Answer 16

• TR can functional or organic
  o Functional TR: RV dilation/failure from ↑Rv afterload
   PH, MV stenosis, CM
  o Organic TR: dz of TV/apparatus
   Bacterial endocarditis, rheumatic, RV infarction

Question 17

Hemodynamic assessment of TR

Answer 17

• RA pressure tracing: large systolic wave (v)
• Jugular venous tracing: s wave present
• Systolic wave: precedes/blend with normal venous filling (v) wave
  o Severe TR: s and v are fused forming one single regurgitant wave
• Distinction of organic vs functional: difficult
  o If systolic RVP >60mmHg → functional TR
  o If systolic RVP = 40mmHg → significant organic component