CARDIAC CASE SERIES RAMUS INTERMEDIUS

An over view

MERCURY IMAGING INSTITUTE SCO 172-173 SEC 9C CHANDIGARHMERCURY IMAGING CENTRE SCO 16-17 SEC 20D CHANDIGARH

Trifurcation of the left main coronary artery..................................

• The left main coronary artery instead of bifurcating into two , sometimes trifurcates into three vessels.(LAD, LCX, Ramus)

• The real incidence of trifurcations could vary between 10% to 30%.

What course ramus intermedius takes ?

• It generally goes in the angle between the LAD and the LCX.It may either behave like a large OM or a diagonal branch.It supplies the lateral free wall of the LV .The peculiarity of this vessel is it does not run in a anatomical groove .It simply slides over the free surface of LV.Rarely, a very abnormal course of ramus, criss cross the aorta and pulmonary artery .

What is the significance of ramus for an interventional cardiologist ?

PCI in ramus is a rare opportunity for a cardiologist .If the ramus is involved adjacent LAD and LCX is also likely to be involved .So it would logically be a multivessel , complex angioplasty.Isolated ramus lesion could be tackled easily.Another issue here could be ,since this vessel is not within any anatomical groove stent deployment would have a poor support and prone for mobilisation and migration .

LEFT MAIN

LAD

LCX RAMUS INTERMEDIUS

RAMUS DOES NOT MOVE IN THE GROOVE

RAMUS INTERMEDIUS

RAMUS INTERMEDIUS

Base image -Ramus intermedius originating

from the left main

Some facts about coronary circulation......

• Left and Rt coronary arteries carry about 250ml of blood per minute .

• Atleast one artery follows all the grooves of the heart .

• In the left side ,  left main coronary artery (LM) originates in the left coronary sinus (Size varying between 1mm -20mm)  and usually bifurcates into LAD and LCX.

• The left anterior descending artery (LAD) runs in anterior interventricular  groove while , 

• The right atrio ventriculo groove carries the right coronary artery(RCA) .

• Left  circumflex artery (LCX) traverses the  left atrio ventricular groovegroove

• The most inconstant branch is the posterior descending artery (PDA) which runs in the posterior interventricular  groove.PDA  can arise from either RCA, LCX or both or even from LAD.The major branches of LAD are called diagonal and septal  while the branches of LCX are called obtuse marginal(OM).There can be two to three diagonal and OMs.