When performing a minimally invasive AVR or MVR via a right mini-thoracotomy approach, assessing whether you are in the right interspace is sometimes questionable.  Even after performing thousands of cases, I question this at times. I have come to the conclusion that there is one landmark that I need to see in order to confirm that I have entered the correct interspace.  That structure is the Right Superior Pulmonary Vein.

During a mini AVR, after instituting CPB and opening the pericardium, if I see the RSPV directly in line with interspace that I entered, I know that I should be able to perform the operation, even if the aorta is displaced. It is key to then take your time and place as many pericardial stay sutures as needed to develop the exposure. This is crucial to optimizing the exposure. (TOP picture)

During a mini MVR, after instituting CPB and opeing the pericardium, if I see the RSPV directly in line with the interspace that I entered, or one interspace above the site that I entered, I know that I am in the correct interspace. I don’t what to be in line with the IVC. This will be very low and if this were the case, I would move to the next higher interspace. Again, use the pericardial stay sutures to optimize exposure. (BOTTOM picture)