Introduction
The Ross operation, also known as the switch procedure, is a cardiac surgical method in which the patient's own pulmonary valve is used to replace the damaged aortic valve, followed by the use of a pulmonary homograft to replace the pulmonary valve.
Aortic valve replacement is occasionally required in some kids and babies for a number of reasons. A prosthetic valve cannot be inserted since there are no small-sized aortic valves, and because the kid will grow, the prosthetic valve will stay the same size and cause symptoms of left ventricular outflow tract blockage.
Additionally, some patients prefer a Ross operation because they do not want to take oral anticoagulant drugs for the rest of their lives.
The Ross method, in contrast to a prosthetic valve, offers excellent hemodynamics and almost little risk of embolic consequences. Finally, the valve develops along with the infant. Sadly, it is now understood that the Ross method has drawbacks as well; the pulmonary homograft will get regurgitation or stenosis after 15-20 years, requiring a different treatment.
The Ross technique was created in the late 1960s and has subsequently been applied several times. It is still the only procedure that enables the replacement of the aortic valve with a live valve substitute.
The fundamental ideas guiding the initial approach have been continually updated over time to improve the surgical result. The anatomy of the aortic valve, indications, contraindications, supplies, people, readiness, method, complications, and clinical importance of the Ross surgery are all covered in depth in this chapter.
Complications
The following are some possible Ross procedure side effects:
- Aortic dysfunction
- blockage of the right ventricular outlet
- Autograft aortic dilatation
- Allograft stenosis in the lungs
- brain-vascular incident
- Ischemia and myocardial infarction
- Hemorrhage
- discomfort in the lungs
- responses to drugs
- blood changes
- Arrhythmias
- Disease Death
Surgery-related complications affect 3-5% of patients, and early death is 1%. The fatality rates are quite low in places with experience. At 10 years, long-term survival was reported to be 80–90%, and at 20 years, it was 70–80%.
Although it is uncommon, early autograft failure might happen during the first six months. The majority of the time, technical issues like leaflet damage or distortion brought on by the valve harvesting are at blame. In most series, the pulmonary homograft lasts for 15 to 20 years until calcific degradation causes regurgitation or stenosis. In contrast, open heart surgery is no longer used in the percutaneous installation of pulmonary valves.
There is no question that the Ross method is better than artificial valves. Aortic regurgitation can, unfortunately, occur in certain patients after the Ross operation due to progressive growth of the new aortic root, especially when the aortic and pulmonary roots were mismatched during the first surgery.
Patients who undergo the Ross surgery have little lifestyle limitations and do not need to take anticoagulation. Additionally, they get unrestricted access to fitness programs. The Ross treatment is difficult, and patients must be monitored for the rest of their lives. Reoperations have been rare, and the morbidity of REDO open heart surgery will be minimized with the advent of percutaneous valve implantation procedures.
Biology and Anatomy
The heart has four chambers. Right and left atria and right and left ventricles are the names of the top two chambers, respectively. The atria and ventricles are divided by atrioventricular valves. There are two semilunar valves: the aortic valve separates the left ventricle and aorta, and the pulmonic valve divides the right ventricle and the pulmonary artery.
Blood that has to be oxygenated is pumped by the right side of the heart into the pulmonary artery at a lower pressure. Blood is pumped into the systemic circulation by the left side of the heart at a significantly greater pressure. As a result, the heart's left side valves are under more pressure.
It is crucial to understand the left major coronary artery's architecture and its take-off throughout the Ross operation. The surgeon should also be familiar with the left coronary artery's path, its proximal septal branches, and how they connect to the aortic root and the right ventricular outflow tract.
In order to make the dissection of the pulmonary autograft easier, the surgeon should be aware of the subpulmonary conal musculature before collecting the tissue. Finally, the surgeon has to be conversant with the location of the conduction system if the left ventricular outflow tract needs to be enlarged (a Ross Konno surgery).
Procedure or Therapy
The Ross method starts with the conventional exposure of the heart and aorta after a median sternotomy, then establishes cardioplegia and starts cardiopulmonary bypass. A centimeter or so above the right coronary artery's (RCA) origin, the ascending aorta opens transversely. The aortic valve is examined once the aorta is opened.
The valve could be fixed in various circumstances. In the event that repair is not feasible, the pulmonary artery is opened and the pulmonary valve is examined to make sure it has a normal anatomical structure. The defective aortic valve is removed, the coronary buttons are prepped, and the aorta is split from the aorta if the Ross surgery is chosen to be performed. The pulmonary valve is then removed.
The primary pulmonary artery (PA) is opened transversely proximal to the bifurcation if there are no anomalies. Next, the pulmonary valve (PV) is examined for flaws. Again, if there are no problems, the complete root technique is used to replace the valve.
90% of the time, the complete root technique is preferred since it has the lowest chance of lung autograft failure. Occasionally, alternative methods, such as the sub-coronary, sub-coronary with retained noncoronary sinus, or cylinder approaches, maybe a preferable option based on the anatomy.
We discuss the complete root approach in this post because it is the most widely applied technique. Pushing the root away from the surgical plane and starting the complete root approach are the first steps.
We discuss the complete root approach in this post because it is the most widely applied technique. The root is first pushed upward and out of the surgical plane to begin the whole root approach. The right ventricular outflow tract (RVOT) is then visible via the incision after the posterior PA root is severed from the muscle.
Following the PA's detachment from the aorta, the portion closest to the pulmonary valve is marked with a clamp. While dissecting on the lateral side, the surgeon must be cognizant of the left anterior descending coronary artery and the first septal.
The anterior right ventricle is divided and the posterior right ventricular muscle is partly scored after creating an opening into the RVOT. The pulmonary artery root is then cut out and separated. After gently removing the Ostia with buttons from the original aorta, the aortic valve and root are removed next.
After the pulmonary valve has been taken out, the aortic root implant is sized and prepped.
The pulmonic autograft is now anastomosed to the LVOT, the right and left coronary arteries are reimplanted onto the autograft, the pulmonic autograft is then anastomosed at its proximal end, and hemostasis is established.
The pulmonary root is then implanted with a cryopreserved pulmonary homograft that has been appropriately trimmed. Transesophageal echocardiography is performed to evaluate the function of the autograft and the homograft after weaning from cardiopulmonary bypass.
To confirm that the aortic and pulmonary valves are both operating correctly before discharge, an echocardiography is performed once more. After that, echos are used to check on patients every 4-6 weeks. Prior to any surgery, it's critical to give patients antibiotics.
Clinical Relevance
Numerous investigations have demonstrated that this technique has a very low death rate and long-term therapeutic success.
This method avoids the requirement for oral anticoagulation, which would have been required for this specific set of patients since they would have required mechanical valves because it employs biological valves instead of those.
Additionally, the Ross surgery can delay aortic valve replacement by up to 20 years. There are likely two causes for this. One is that the pulmonary valve used to replace the aortic valve can expand as the patient grows, and the other is that the right side of the heart has lower pressures, which puts less strain on the pulmonary valve replacement and, as a result, lowers the failure rate.
Overall, this technique is a great way for kids and young people to increase survival. It is still the only procedure that enables the replacement of the aortic valve with a live valve substitute.
other information: Click hear
Comments
Post a Comment