Weighing up the Ross procedure

One of the world's top cardiologists has paid tribute to SA-born heart surgeon Donald Ross at the Sixth World Congress of Paediatric Cardiology and Cardiac Surgery, currently held in Cape Town.

Describing Ross, who performed the first pulmonary autograft operation in 1967 in the UK, as “Kimberley's most brilliant gem”, Professor Frank Hanley critically assessed the relevance of the so-called Ross procedure which he said remains an important development in the field of cardiac surgery.

The exact procedure involves the replacement of the patient's diseased aortic valve with his or her pulmonary valve. A pulmonary allograft which is taken from a cadaver then replaces the patient's own pulmonary valve.

Paul Stelzer, one of the strongest proponents of the Ross procedure in the US, describes the operation as the “extensive reconstruction of the high-pressure 'plumbing' of the aortic root using the delicate material of the pulmonary artery”.

“For aortic disease, the Ross procedure at first placed a strong emphasis on maintaining the native aortic root,” said Hanley. “There was the benefit of living tissue, but no mention was made of possible growth of the valve, for example, in child patients.”

However, since then the technique has evolved considerably. “There have been a total of 652 academic publications in the 46 years since the first pulmonary autograft was performed,” said Hanley. “This is partly due to an expansion of the concept and the technical variations to the procedure.”

Aortic root replacement techniques

One of the unanticipated developments of the Ross procedure has been the wide adaption of aortic root replacement techniques. “This is something that Ross himself does not approve of,” said Hanley, referring to the aortic root replacement technique which many surgeons prefer because it is easier to perform. Ross, however, favours the original inclusion technique which has fewer negative side effects.

“Currently, the feeling among surgeons is divided equally when it comes to whether they should perform the Ross procedure on adult patients or not,” said Hanley. “The long-term risks of the operation include the development of neo-root dilation and aortic insufficiency (AI), specifically in male patients with dilated aortic annulus who suffered from preoperative AI.”

While cardiac surgeon Nicholas Kouchoukos and others have called for a moratorium on the Ross procedure, Hanley believes the operation has its merits, particularly for young patients.

“When dealing with critical aortic stenosis in the neonate, there is a need for something other than balloon valvotomy, where the only real patient selection is whether the infant is a hypoplast or not,” he said.

Benefits

Explaining the benefits of the so-called Ross-Konno procedure, Hanley said the question was not whether it should be used for neonatal aortic stenosis, but why it wasn't being used more often. “Young children have the greatest potential to benefit from the growth of the graft,” he said. “As opposed to adults, the root replacement technique is well suited in this patient population: infants have a tiny left ventricular outflow tract, the pulmonary root is prepared, while the extension to a Konno operation adds minimal risk.”

In conclusion, Hanley said that despite its detractors, the Ross procedure is likely to continue to be performed for many years to come. “He was a courageous pioneer who added massively to the body of knowledge of cardiac surgery. Clearly the Ross principle will stay with us, but it does need to be modified.”

- (Written by Katherine Graham, Press office of WCPCCS2013)