The Expanding Role of Minimally Invasive Cardiac Surgery: The NYU Experience
The NYU Department of Cardiothoracic Surgery began research in less invasive forms of cardiac surgery in 1994 and introduced the Port Access approach for mitral valve surgery in an FDA sponsored trial in 1996. Since that time the use of minimally invasive cardiac surgery has expanded dramatically, and NYU surgeons now have experience in 1196 patients using these techniques (Table I).
In reviewing this experience, several trends have been observed. First, in the treatment of coronary artery disease, several less invasive forms of surgery have become available and are used in selected populations. Techniques include (1) minimally invasive direct coronary artery bypass (MIDCAB), which is preformed through a mini-thoracotomy incision without cardiopulmonary bypass, (2) off-pump coronary artery bypass (OPCAB), which is preformed through a sternotomy incision without cardiopulmonary bypass, and (3) Port Access, which uses a balloon catheter system to perfuse the patient and protect the heart, allowing multi-vessel bypass (and valve surgery) through a mini-thoracotomy incision.
Each technique has its advantages. In a comparative trial between Port Access and conventional surgery formulti-vessel coronary bypass, Port Access patients had less pain, less systemic stress response, and recovered in approximately one-half the time, based on the Duke activity index score. Similarly, important advantages were seen in patients having either form of off-pump surgery (OPCAB and MIDCAB). Since these techniques avoid cardiopulmonary bypass, the risk of stroke and other bypass related complications is diminished. A NYU comparison in high risk patients who have atheromatous disease of the aortic arch and required coronary bypass demonstrated that patients who received OPCAB or MIDCAB had one-half the risk of stroke and death compared to conventional surgery. Currently at NYU approximately 25-30% of patients requiring CABG receive a less invasive operative approach, either Port Access, MIDCAB or OPCAB. This strategy, which allows "risk stratefication" based on anatomy and risk factors such as severe vascular disease or renal failure, has led to improved overall results and a lower risk.
Even more striking than the results with coronary bypass surgery has been the impact of minimally invasive approaches on valvular surgery. The minimally invasive approach has become the standard of care for most patients requiring isolated valve repair or replacement, with the Port Access approach is used for virtually all mitral valve surgery (Fig 1).
Results have been exceedingly good (Table 2), with an extremely low operative risk, less bleeding, less risk of infection, and shorter overall recovery. Follow-up studies have shown that valve repair durability is equivalent to that achieved with conventional surgery. Thus, the short term risks are reduced, with equivalent long term results.
In summary, the large and extremely favorable NYU experience with minimally invasive cardiac surgery suggests that this form of less traumatic surgery is now preferred for most patients requiring aortic or mitral valve surgery, for ASD repair and for atrial myxoma excision. Patients requiring coronary artery bypass are risk stratified using either conventional surgery, Port Access, MIDCAB or OPCAB, which has lowered the overall risk significantly. Patients having minimally invasive cardiac surgery require less blood, have fewer infections and recover more quickly. These emerging new technologies are having a dramatic impact on patient care, lowering the overall morbidity, pain and suffering associated with heart surgery in the year 2000. Further improvements, ranging from robotics to gene therapy, hold promise for future breakthroughs in the upcoming years.
Aubrey C. Galloway, MD
Professor of Surgery
Director, Surgical Research
The NYU Department of Cardiothoracic Surgery began research in less invasive forms of cardiac surgery in 1994 and introduced the Port Access approach for mitral valve surgery in an FDA sponsored trial in 1996. Since that time the use of minimally invasive cardiac surgery has expanded dramatically, and NYU surgeons now have experience in 1196 patients using these techniques (Table I).
In reviewing this experience, several trends have been observed. First, in the treatment of coronary artery disease, several less invasive forms of surgery have become available and are used in selected populations. Techniques include (1) minimally invasive direct coronary artery bypass (MIDCAB), which is preformed through a mini-thoracotomy incision without cardiopulmonary bypass, (2) off-pump coronary artery bypass (OPCAB), which is preformed through a sternotomy incision without cardiopulmonary bypass, and (3) Port Access, which uses a balloon catheter system to perfuse the patient and protect the heart, allowing multi-vessel bypass (and valve surgery) through a mini-thoracotomy incision.
Each technique has its advantages. In a comparative trial between Port Access and conventional surgery formulti-vessel coronary bypass, Port Access patients had less pain, less systemic stress response, and recovered in approximately one-half the time, based on the Duke activity index score. Similarly, important advantages were seen in patients having either form of off-pump surgery (OPCAB and MIDCAB). Since these techniques avoid cardiopulmonary bypass, the risk of stroke and other bypass related complications is diminished. A NYU comparison in high risk patients who have atheromatous disease of the aortic arch and required coronary bypass demonstrated that patients who received OPCAB or MIDCAB had one-half the risk of stroke and death compared to conventional surgery. Currently at NYU approximately 25-30% of patients requiring CABG receive a less invasive operative approach, either Port Access, MIDCAB or OPCAB. This strategy, which allows "risk stratefication" based on anatomy and risk factors such as severe vascular disease or renal failure, has led to improved overall results and a lower risk. Even more striking than the results with coronary bypass surgery has been the impact of minimally invasive approaches on valvular surgery. The minimally invasive approach has become the standard of care for most patients requiring isolated valve repair or replacement, with the Port Access approach is used for virtually all mitral valve surgery (Fig 1).
Results have been exceedingly good (Table 2), with an extremely low operative risk, less bleeding, less risk of infection, and shorter overall recovery. Follow-up studies have shown that valve repair durability is equivalent to that achieved with conventional surgery. Thus, the short term risks are reduced, with equivalent long term results.
In summary, the large and extremely favorable NYU experience with minimally invasive cardiac surgery suggests that this form of less traumatic surgery is now preferred for most patients requiring aortic or mitral valve surgery, for ASD repair and for atrial myxoma excision. Patients requiring coronary artery bypass are risk stratified using either conventional surgery, Port Access, MIDCAB or OPCAB, which has lowered the overall risk significantly. Patients having minimally invasive cardiac surgery require less blood, have fewer infections and recover more quickly. These emerging new technologies are having a dramatic impact on patient care, lowering the overall morbidity, pain and suffering associated with heart surgery in the year 2000. Further improvements, ranging from robotics to gene therapy, hold promise for future breakthroughs in the upcoming years.
Aubrey C. Galloway, MD
Professor of Surgery
Director, Surgical Research