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MCI (P) 050/02/2013 THURSDAY MARCH 7 2013 Your Life. Live it well. ONLY ONE CUT Singapore doctor develops less invasive heart valve operation pages12-14 WIN! Health supplements worth more than $700 and skin care products worth $500 2 DRINK TEA, LOSE FAT Tea can keep your weight under control 10 FRIED RICE PARADISE Make the classic dish using brown rice 22 12 THE STRAITS TIMES MARCH 7 2013 Cover Story Heart surgery with smaller scars Doctors now tackle defective heart valves through smaller JOAN CHEW incisions that hasten recovery I t used to be that patients who had heart valves repaired or replaced would come out of surgery with a scar that stretched the entire length of the sternum or breastbone. It would start right below the neck’s hollow, run down the centre of the chest and end above the abdomen. Patients would carry a 15 to 20cm long scar for the rest of their lives. This traditional method of heart surgery, called full median sternotomy, separates the sternum to expose the fist-sized heart muscle for surgeons to work on. While this is still the standard approach in cardiac surgery, less invasive techniques have been used in recent years by a handful of doctors here, with one even developing his own method. There is no formal consensus on what constitutes minimally invasive cardiothoracic surgery. It is understood that the term refers to operations performed through incisions other than the traditional full median sternotomy. They usually involve smaller incisions, which reduce body trauma, hence potentially reducing pain, scarring and recovery time. Minimally invasive cardiothoracic surgery was first introduced during the 1990s, driven by major improvements in technology. Associate Professor Theodoros Kofidis, head of the division of adult cardiac surgery at the department of cardiac, thoracic and vascular surgery at National University Heart Centre, Singapore (NUHCS), said the move was also a response to changing patient expectations. He said patients used to be grateful for coming out of open heart surgery alive, but soon also expected to have the least possible complications. Improved cosmetic results were later added to their wishlist, which prompted surgeons to adapt to those needs, he said. He set up the minimally invasive cardiac surgery programme in NUHCS three years ago. Since then, he has been using the minimally invasive approach for four in every 10 patients who require surgery on a single heart valve. He has also developed his own method (see page 14). The National Heart Centre Singapore (NHCS) has been using the minimally invasive approach in heart valve surgery since 2007. SMALLER INCISIONS Minimally invasive heart surgery can be used to fix faulty heart valves, a hole in the heart, irregular heartbeats and for coronary artery bypass graft surgery to improve blood supply to the heart. However, this technique is not used when many defects occur at the same time. During heart valve surgery, sternotomy can be done with a smaller incision which cuts through half the sternum, said Dr Lim Yeong Phang, a cardiovascular and thoracic surgeon at Gleneagles Hospital and Mount Elizabeth Novena Hospital. The scar would be 6 to 8cm long. The operation, known as upper sternotomy, still involves cutting the breastbone and joining it back with steel wires. Dr Lim said any bone fracture requires six weeks to heal properly, during which patients should not drive or lift anything heavier than a newborn baby. Thus, another approach which does not involve bones but cuts through just soft tissue and muscles would speed up the healing process. Prof Kofidis said a patient may be in hospital for 10 days after undergoing full median sternotomy and eight or nine days after upper sternotomy. A procedure called right minithoracotomy could further reduce the stay to about five days, he said. In this procedure, the surgeon makes a 4 to 10cm incision between the ribs on the right chest and another three to five incisions, or portholes, near the area for the passage of surgical instruments. Each porthole is between 5 and 10mm. No bone is involved. The operation also requires a 4cm incision in the groin, through which doctors insert tubes, called cannulas, to be connected to a heart-lung machine that takes over the functions of the patient’s heart and lungs during the operation. This approach has been used on patients at NUHCS since 2009 and with robot-guided instruments since 2010. Eleven patients of NHCS have also had robot-assisted mitral valve repair through minithoracotomy. The mitral valve is one of four heart valves which should open one way only to allow blood through. Businessman Craig Andrew McEvoy, 49, was lucky to benefit from less invasive surgery. The Australian is the only patient at NUHCS who has undergone Prof Kofidis’ modified minithoracotomy. His leaky mitral valve was repaired through a single 6cm incision in his right chest. For three months last year, he was hospitalised when a streptococcus infection affected his brain and heart. He also had other problems such as water collecting in his abdomen, inflammation of the pancreas and a fatty liver. Mr McEvoy, who is moving to Bangkok after living here for 20 years, said he used to drink and smoke heavily while entertaining customers at his pub. Prof Kofidis said the bacteria had perforated Mr McEvoy’s mitral valve so it could not close tightly and caused blood to flow back wrongly into the heart. Mr McEvoy and his 48-year-old Thai wife, Mrs Bunsri McEvoy, were sold on the prospect of a faster recovery, as he was in poor health and had lost 20kg during the Fixing faulty valves ST PHOTOS: NG SOR LUAN, AZIZ HUSSIN Mr Craig Andrew McEvoy (left), who had a minimally invasive procedure on his heart valve, has a smaller scar compared with Mr Choo Kok Weng (above), who had conventional surgery. three months when he was hospitalised. He was admitted to NUH for 17 days after the heart valve surgery – longer than if he had been a healthier patient. The businessman, who has cut down on his smoking, recalled: “With me pushing 50 years of age, I was not too bothered by the size of the scar. But as I love going to the beach, the small scar was definitely an added bonus for me.” NOT FOR EVERYONE Despite the appeal of smaller scars, not everyone is suitable for less invasive techniques. Dr Tan Teing Ee, a senior consultant at the department of cardiothoracic surgery in NHCS, said patients who are unstable, have other serious medical conditions or lung disease, have a small rib cage or require other cardiac procedures, such as a bypass, at the same time are not suitable. One such patient is church worker Choo Kok Weng, 50, who was diagnosed with coronary artery disease and mitral regurgitation last December. He had an operation on Jan 25 to repair his mitral valve, which did not close as tightly as it should, and also had a coronary bypass to replace a blocked heart vessel with one taken from the chest wall. He was hospitalised for five days at Gleneagles Hospital and now has an 18cm scar, but he is not too bothered. Instead, he is thankful his ailments were detected before a heart attack endangered his life. Sometimes, surgeons have to revert to the traditional approach in the event of complications during surgery. In one study published in the European Journal Of Cardio-Thoracic Surgery in 2008, four out of 1,339 patients who went in for minimally invasive mitral valve repair for mitral regurgitation had to have the surgery converted to sternotomy because of problems such as excessive bleeding and tears in the aorta, the main artery arising from the heart. The authors found that 83 per cent of patients reached the five-year survival rate, while 96 per cent did not require another mitral valve-related operation in that same period. A drawback of this study was that there was no control group to compare against as the Leipzig Heart Center of the University of Leipzig in Germany had made minimally invasive mitral valve surgery its procedure of choice since the late 1990s. In other studies, 92 per cent of patients who underwent sternotomy survived for at least 10 years, while 93 per cent of patients did not require another operation in the five years afterwards. Another study published in The Journal Of Thoracic And Cardiovascular Surgery last April compared early outcomes from 138 patients who had minimally invasive aortic valve surgery by minithoracotomy and matched them to a control group of 138 with conventional full sternotomy. Overall, 0.7 per cent of patients died in hospital, with no difference between the two groups. The incidences of stroke, renal failure and wound infection were similar. Those who were operated on using the less invasive approach also had a lower incidence of post-operative irregular heartbeat and blood transfusion and shorter ventilation time and hospital stay. CHALLENGES AND COMPLICATIONS At least three cardiothoracic surgeons said they did not think minimally invasive approaches would become the standard of care for heart valve surgery yet. They said the promising results from overseas studies are difficult to replicate here as surgeons do not have a large pool of heart valve patients to hone their expertise in this technique. Dr Lim has performed thoracotomy only once, in 2009, on a patient whose “unique anatomy” made him unsuitable for sternotomy. His heart was displaced to the right side of his chest as his right lung had been removed earlier, so the right thoracotomy was optimal. Dr Sriram Shankar, a consultant cardiothoracic and vascular surgeon at Gleneagles Medical Centre, said he offers thoracotomy only to patients who have had sternotomy previously. Scar tissue forming on organs after the first operation would make it complicated to do another operation at the same spot in the sternum, he said. He said complications, such as internal bleeding, can be more easily tackled if a patient has had sternotomy, as doctors can simply remove the steel wires on the sternum to access the heart in intensive care, which takes five minutes. On the other hand, a patient who had thoracotomy would have to be wheeled back into the operating theatre to have his chest cracked open using sternotomy. [email protected] Improving technology has enabled more people with defective heart valves to have them repaired instead of replaced, which preserves heart function better and has a lower risk of complications. The mitral valve separates the two left chambers of the heart – left atrium and left ventricle – while the aortic valve lies between the left ventricle and the aorta, which pumps oxygen-rich blood from the heart to the rest of the body. Among the four valves, the mitral valve and the aortic valve are more vulnerable to damage. The mitral valve is prone to leakage and infections, while the aortic valve endures high blood pressure to prevent the backflow of blood leaving the heart. Associate Professor Theodoros Kofidis, head of the division of adult cardiac surgery at the department of cardiac, thoracic and vascular surgery at National University Heart Centre, Singapore (NUHCS), said problems with these two types of valves – mitral and aortic – make up more than seven in 10 of all heart valve diseases. The National Heart Centre Singapore (NHCS) handles 250 cases of heart valve surgery a year, of which about half are related to faulty mitral valves. In 2005, 46 per cent of patients who had mitral valve surgery had their valves repaired rather than replaced, a number that has gone up to 69.8 per cent in 2011. At NUHCS, 48.6 per cent of patients who underwent mitral valve operations last year had repairs done, up from 30 per cent in 2010. Valves control the flow of blood into and out of the ventricles in only one, correct direction. They can fail due to age-related degeneration, rheumatic heart disease, endocarditis (infection of heart valves) and heart attacks. When a valve is unable to close properly and tightly, some of the blood that has already been pumped through it can leak back in what is known as regurgitation. This forces the heart to work harder and, over time, can damage the heart. If a valve becomes narrowed, sometimes due to the accumulation of calcium deposits with age, blood flow through it is restricted and again, puts a strain on the heart. Such problems give rise to symptoms such as fatigue, chest pain, shortness of breath and heart palpitations, which may eventually lead to heart failure, when there is insufficient blood flow throughout the body. Patients may be treated with medication first to relax the heart and relieve their symptoms. Dr Tan Teing Ee, a senior consultant at the department of cardiothoracic surgery in NHCS, said surgery is used if symptoms become severe or if a two-dimensional echocardiogram (ultrasound of the heart) shows that the heart is unable to maintain adequate blood circulation. NATURAL IS BEST Less than 20 years ago, it was conventional to replace faulty valves with biological or mechanical replacements, said Dr Sriram Shankar, a consultant cardiothoracic and vascular surgeon in private practice at Gleneagles Medical Centre. But increasing understanding of valves means the different parts – such as the leaflets (cusps of the valve), their surrounding papillary muscles and chords (string-like structures that attach the leaflets to the papillary muscles) – can be repaired. Dr Lim Yeong Phang, a cardiovascular and thoracic surgeon in private practice at Gleneagles and Mount Elizabeth Novena hospitals, said it was only in the last five years that surgeons here have begun to do repair work on valves more routinely. This is preferable to valve replacements, as people who have had such surgery are required to take blood thinners to reduce their risk of blood clots forming on the replaced valve, which can lead to strokes and death. Dr Shankar said mechanical valves made of titanium and pyrolitic carbon are known to last 80 years but require patients to be on blood thinners for life. On the other hand, biological valves made of cow or pig tissue require up to three months of blood thinners but last only 10 to 12 years, so additional operations would be needed for younger patients. Dr Shankar added that any type of artificial valve replacement would not be able to pump as much blood out of the heart as the patient’s natural valve could. As a result, his heart function can drop by 20 per cent. Valve repair is generally preferred now, unless the valve is so severely damaged that it has to be replaced. Only aortic valves are replaced more often than they are repaired. Dr C. Sivathasan, a consultant cardiothoracic and vascular surgeon at Mount Elizabeth Medical Centre, said problematic aortic valves are usually calcified or hardened, so it is not ideal to repair them. Doctors note that valve disorders are set to rise with a growing and ageing population. Prof Kofidis said overseas studies have shown that in industrialised countries such as Singapore, 3 per cent of the population have heart valve disease, of whom half will need surgery. The prevalence rises to 11 per cent for those aged 75 and above. By Joan Chew 14 THE STRAITS TIMES MARCH 7 2013 FROM SIX CUTS TO ONE Current method: Two incisions, four portholes ATRIAL RETRACTOR Device with three large ar ticulated ar ms holds the incision in the hear t open for the surgeon to reach the valves inside. It is clamped to the bed to prevent movement. AORTIC CROSS-CLAMP This clamps the aor ta to stop the flow of blood. Its handles protrude from the body . CAMERA CARBON DIOXIDE AND SUCTION TUBES Carbon dioxide, which is denser than air , is pumped around the hear t to pre vent air from entering the bloodstream. An air bubble trapped in a blood vessel can block an ar tery and cause a stroke or hear t attack. Blood is constantly suck ed out to k eep the surgical vie w clear for the surgeon. MAIN SURGICAL INCISION The surgeon gains access to the hear t through this incision, which is betw een 4 and 10cm. New method: One incision, no portholes This new technique, a world-first, eliminates all portholes occupied by the camera, clamp and tubes. FEMORAL INCISION Through this 3 to 4cm incision, tubes are inser ted into the femoral vein and femoral ar tery and connected to the heart-lung machine during surger y. After surger y is completed, the vessels and incision are stitched closed. Note: Drawings have been simplified for ease of representation. ONE SURGICAL INCISION The new technique pro vides the surgeon access to the hear t from just one 6cm incision on the side of the chest. Aortic cross-clamp with handles that can be detached FEMORAL HOLES The two tubes connected to the hear t-lung machine are now passed through two 5mm holes in the skin. After surger y, a de vice deliver s sutures through these holes to close the cuts in the blood vessels. The holes do not need to be stitched later . Getting inside the heart 3 Aorta distributes oxygenrich blood to the rest of the body. 2 DETACHABLE AORTIC CROSSCLAMP After the clamp is in place, the handles can be remo ved so they will not tak e up space around the incision in the chest. Needles Incision Holes 2cm 8cm 1 Sutures MODIFIED ATRIAL RETRACTOR A newly developed flexible steel plate is used to hold the incision in the hear t open, without the need for a bulk y retractor. 1 T wo sutures and their needles are passed through the holes of the retractor. The y are either 2 pulled out of the 6cm incision or , more frequently, 3 passed through the skin of the chest, before the y are clamped to hold the plate in place. If the y are pulled through the skin of the chest, each hole is less than 1mm, so it does not cause an y wound that needs to be stitched later . Source: Associate Professor Theodoros Kofidis, head of the division of adult cardiac surgery at the department of cardiac, thoracic and vascular surgery at National University Heart Centre, Singapore ST GRAPHICS: MIKE M DIZON O ne doctor here has entered the race to make surgery on faulty heart valves less invasive – using modified surgical tools to reduce the number of cuts made in the body from five or six to one. Associate Professor Theodoros Kofidis, senior consultant and head of adult cardiac surgery at National University Heart Centre, Singapore (NUHCS) successfully repaired 49-year-old businessman Craig Andrew McEvoy’s valve through a single cut on the chest last December. Prof Kofidis, 43, calls the procedure the single incision minimally invasive cardiac surgery. Most patients with mitral and tricuspid heart valve disease, estimated to exceed 200 here each year, may benefit from the new operation, he said. The mitral valve separates the two left chambers of the heart, while the tricuspid valve separates the two right chambers. They can become torn or leaky because of ageing, heart failure and congenital defects and need to be surgically repaired. His main innovations include modifying the atrial retractor, a tool which holds the incision in the heart open to expose the valves inside; and the aortic cross-clamp, which is used to stop blood flowing through the aorta during surgery. The atrial retractor, which occupies a porthole in the chest wall, is a bulky instrument with three arms which takes up standing space in the operating theatre. Prof Kofidis’ replacement is a malleable steel plate that is inserted through the single incision. It is flexed to hold the incision in the heart open and clamped outside the body to hold it in place. No porthole is required. After the operation, it is simply removed. A paper on this was published in The Annals Of Thoracic Surgery in 2011. The aortic cross-clamp occupies another porthole in the chest wall. Prof Kofidis used one invented by an Italian surgeon, which has handles that can be detached and removed while it is in use. This means that it can be passed through the single 6cm incision between the ribs and will not require a separate porthole. Another innovation involves the incisions that are made in the thigh. They allow blood to be pumped out and in through the femoral vein and artery respectively and passed through a heart-lung machine, which takes over the function of the patient’s heart and lungs during the operation. In the conventional minithoracotomy, the blood vessels are accessed through a 4cm skin incision. After the surgery, the cuts in the vessels are stitched closed before the skin incision is also closed. In Prof Kofidis’ procedure, the tubes to connect these two blood vessels to the heart-lung machine are passed through holes smaller than 5mm in the skin, which do not require stitching. Prof Kofidis then uses a special device that delivers sutures through the skin to close the vessels, without the need for any skin incisions. This device is already used in less major heart procedures such as the insertion of a stent to keep a partially blocked blood vessel open, he said. Besides the improved cosmetic outcome, the new technique may also help cut complications from surgery, though this will have to be shown in clinical studies. Patients who cannot have the procedure are those who are severely obese, have aortic valve leakage or have less conventional heart anatomy. A thick layer of fat in the body can obstruct a surgeon’s view during minimally invasive, single incision surgery, Prof Kofidis said. A subsidised patient at NUHCS pays between $3,100 and $13,200 for the new procedure. This is $2,000 more than what he would pay for full median sternotomy, which costs between $1,100 and $11,200, depending on the level of subsidies. By Joan Chew