Traditionally, over the past few decades, heart surgeries were performed through sternotomy (a large cut on the chest and splitting the breast bone) to gain access to the heart. Not only does the large incision result in a long, unsightly scar, but it causes more pain, more physiological trauma, a longer hospital stay and a longer recovery period.
As heart surgery techniques and technology improved over time, surgical techniques have been improvised to reduce the pain and suffering for the patients while maintaining the safety and effectiveness of the surgery.
Minimally invasive cardiac surgery (MICS) is well developed and recognised now in most parts of the world. Following strict criteria, the length of the cut for MICS is defined as less than 4 inches.
To date, MICS has been used for coronary artery bypass surgery (CABG) and cardiac valvular surgery.
For minimally invasive direct coronary artery bypass surgery (MIDCAB), the left internal mammary artery (LIMA), which is the best path and offers the best long-term patency, can be harvested via 3 different ways:
- A small anterior thoracotomy of 6 – 8cm in length
- Video-assisted thoracoscopy (VATS)
- Robotic-assisted thoracoscopy
Each of these approaches has its own pros and cons. There is a certain learning curve and hence it is important for the surgeon to be well versed in such approaches.
Following the harvest of LIMA, the artery will then be connected to the most critical left anterior descending artery to offer patients the best long-term outcome. During the operation, because of the off-pump technique and the least handling of the heart, the patient has a more stable blood flow and reduced bleeding.
MICS is also being widely used for isolated cardiac valvular surgery, especially mitral valve repair / replacement, tricuspid valve repair / replacement and aortic valve replacement. Most commonly, this is done through a 6 – 8cm cut in the sternum. For mitral and tricuspid valve surgery, it can also be approached via a small cut through the chest or via robotic-assisted surgery.
In the hands of a trained heart surgeon, these minimally invasive approaches will offer patients the least physical and psychological trauma while preserving the aim of the surgery in utmost safety. Typically, after MICS, the patient can be discharged from the hospital in 3 – 4 days' time and resume most of their usual activities within 2 – 4 weeks.
This state-of-the-art development of MICS has continued to evolve and has also been successfully applied in other heart surgeries, including atrial septal defect closure, tricuspid valves repair, DOR procedure (chronic heart failure operation), and removal of left ventricular blood clot, arrhythmia surgery and ventricular septal rupture.
Hybrid Approach
In the current era of medicine, it may be difficult to offer perfect treatment options for a patient with complex heart disease. In a patient with ischaemic heart disease, some coronary arteries may be more suitably dealt with by angioplasty and stenting, while some coronary artery, especially the left anterior descending artery, may be better off with a CABG and LIMA connected to it. In a patient with cardiac valvular disease coupled with coronary artery disease, this patient will undergo a full sternotomy using standard methods to fix both the valve and coronary artery stenosis.
However, with the development of MICS and increasing team work between cardiologists and cardiac surgeons, the hybrid approach to a patient with cardiac conditions can now offer a new view in treatment planning and work towards the best interest of patients.
In a patient with multiple coronary artery diseases, LIMA – LAD anastomosis offers the best long-term patency and patient survival. Total artery coronary artery bypass often appears attractive in terms of clinical outcomes. However, in real life, this happens only in less than 20% of the cases.
On the other hand, although percutaneous coronary intervention (PCI) with stents is least invasive among all revascularisation interventions, and the technology of coronary stents has evolved dramatically, its outcome still cannot match LIMA – LAD, which offers a 20-years patency rate of more than 90%.