Minimally Invasive Valve Surgery

The term "minimally invasive" for valve surgery refers to incision size and approach, rather than limiting crossclamp and perfusion times, since cardiopulmonary bypass is necessary. Several years ago alternative approaches to a standard median sternotomy were introduced as an improvement based on presumed decreased pain and shortened hospital stays. The initial approach introduced was a right parasternal approach to gain access to the aortic, mitral and tricuspid valves. Pain, because of the thoracotomy and excision of costal cartilages, as well as limitation of exposure if a problem arose limits the usefulness of this parasternal approach. The procedure evolved to a sternal transection to approach the aortic valve with transection of both internal mammary arteries. The reported justification for transection of both internal mammary arteries was that patients requiring aortic valve replacement alone rarely presented later for coronary revascularization. In terms of sternal devascularization, it was felt that retrograde and collateral flow via the distal internal mammary would be sufficient to not increase the risk of infection. This further evolved into a partial upper median sternotomy for aortic, mitral and tricuspid valves, with hemi-transection of the sternum into the right 3rd or 4th interspace, or a "j" type of sternotomy (Fig 9.1). An alternative approach is the "J" incision made from the right 1st interspace to the midline of the sternum, and then down to the right 4th or 5th interspace.

These partial sternotomy incisions are superior to the right thoracotomy because of decreased pain and the ease with which the partial sternotomy can be converted to a full sternotomy should the need arise. It remains unresolved whether indeed these minimal incisions truly decrease patient morbidity or hospital stays. Cardiopulmonary bypass times are generally at least as long as their full sterno-tomy counterparts.

Another approach adopted several years ago involves Port-Access technology, wherein a very small thoracic incision is constructed to perform valve (or coronary) surgery. Fully endoscopic heart surgery has been possible with the technique. CPB is achieved via the femoral artery and vein route. A balloon catheter retrogradely placed from the femoral artery and inflated in the ascending aorta serves as a functional crossclamp and antegrade cardioplegia delivery device. Coronary sinus cannulation for retrograde cardioplegia is endovascularly achieved via a central vein under transesophageal echocardiography guidance. Port-Access has

Fig. 9.1. Minimal "j" sternal incision for exposure of cardiac valves.

made possible the feat of completely endoscopic valve (and coronary) surgeries. Again, the benefit remains primarily incision size, since the bypass and ischemic times generally exceed their more standard counterparts. Furthermore, another incision is required in the groin to access the femoral vessels. The complexity of the various cannulations and need for fluoroscopy limit wide applicability as well.

Herbal Remedies For Acid Reflux

Herbal Remedies For Acid Reflux

Gastroesophageal reflux disease is the medical term for what we know as acid reflux. Acid reflux occurs when the stomach releases its liquid back into the esophagus, causing inflammation and damage to the esophageal lining. The regurgitated acid most often consists of a few compoundsbr acid, bile, and pepsin.

Get My Free Ebook

Post a comment