Feeds:
Posts
Comments

Posts Tagged ‘unroofed coronary sinus’

All left to right shunts are  acyanotic heart disease to begin with. Cyanosis appears if there is progressive PHT and reversal of shunt .We know this happens late in ASD.(third decade)

It is important to remember some of the  patients  with large ASD  can show significant desaturation without severe pulmonary HT.  This should not be mistaken for Eisenmenger reaction.

How ?

In  any large ASD ,

  • IVC blood can stream into LA by hitting preferentially the lower part of IAS.( It is the old fetal route that heart does not forget  and indulges whenever the  local hemo-dynamics permits !)
  • During straining , (Valsalva and equivalents)  right atrial pressure can exceed LA and small amount of shunts occur across RA.
  • ASD is often (15%) associated with systemic venous anomaly. The common one is persistent LSVC.  LSVC  is usually connected to coronary sinus . If it has a communication with LA (Un-roofed CS) , there can be significant cyanosis .
  • Further , a large ASD can act as a single atrium and considerable mixing happens and cyanosis results.

Finally ,two conditions should always be considered

  • ASD if associated with VPS auguments R-L shunt .
  • TAPVC can be mistaken for Eisenmengerisation of  ASD in bedside which presents as clinical signs of ASD + Cyanosis

* It is useful to recall ,even PFOs can shunt right to left at times of extreme RA pressures like during PEEP ventilation and orthostatic  deoxia in sick ICU patients are reported (If PFO can shunt R-L , why not huge ASD ?)

Final message

Cyanosis  in ASD is not always  an ominous sign .There are few important causes other than Eisenmenger. Though it  occurs intermittently , persistent mild desaturation is also possible.

Read Full Post »

A related article in this blog

Un-roofed coronary sinus

Further reading :

A rare comprehensive review article on Thoracic venous anomalies

Fr0m American journal of  Roentgenology


Read Full Post »

                                               The superior aspect of   coronary sinus and a portion of the left atrium share a common wall .Embryological defects in this area result in a communication between left atrium and coronary sinus. This defect  descriptively called as unroofed coronary sinus .This entity is most commonly associated with persistent left SVC. Extreme form of unroofing is some times termed as absent coronary sinus.

How to diagnose it ?

A high degree of anticipation is necessary in all patients with ASD or LSVC. A dilated coronary sinus in routine echocardiography warrants full investigation. A contrast echocardiography with agitated saline injection in left cubital vein will clinch the diagnosis as contrast enters LA after opacifying the dilated coronary sinus. During  right heart catheterisation catheter course entering coronary sinus and  advancing into LA through the fenestrations (Unroofing)  will confirm the defect.

How do you classify unroofed coronary sinus ?

The morphologic type of URCS was classified as Kirklin and Barratt-Boyes

 Type   I, completely unroofed with LSVC;

 Type II, completely unroofed without LSVC;

 Type III, partially unroofed midportion;

 Type IV, partially unroofed terminal portion

What is the clinical relevance of this entity ?

This entity should be suspected in every patient with persistent LSVC, ( and LSVC should be suspected in every patient with ASD). The hemodynamics is that of an ASD but if sufficient mixing of LSVC blood and LA blood takes place the child will have mild cyanosis.Some times when the coronary sinus is totally absent it will present as a typical dusky ASD picture which can closely mimic a TAPVC clinically.

Surgeons have a greater role in recognising and treating this entity. A typical repair will be done like this

 

Links to some of interesting articles on this topic

Raghib circulation 1965

Read Full Post »