TAVI is feasible in non-surgical patients with pure native aortic valve regurgitation

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A new study, published ahead of print in the Journal of the American College of Cardiology, suggests that transcatheter aortic valve implantation (TAVI) is associated with acceptable results in patients with severe native aortic valve regurgitation without stenosis who are not candidates for surgical valve replacement.

David Roy, Department of Cardiology and Cardiothoracic Surgery, St George’s Hospital, London, UK, and others commented: “There are patients with severe aortic regurgitation and at high or extreme surgical risk for whom conventional aortic valve replacement may be unsuitable and who might benefit from transcatheter-based therapy.” However, they added that although there are anecdotal reports of TAVI being used in patients with severe aortic valve regurgitation without stenosis, there is no collective published data for TAVI in this group of patients. Therefore, the aim of their study was to “collect data and evaluate the anecdotal use of TAVI in pure native aortic valve regurgitation for patients who were deemed surgically inoperable.”


Patients were recruited to Roy et al’s independent, worldwide, multicentre, voluntary registry if they had severe aortic valve regurgitation without stenosis, were unsuitable for surgery because of an extreme risk of complications, and had not previously undergone any form of aortic valve surgery. Of the 43 patients recruited to the study, the mean age was 75.3±8.8 years and there was high prevalence of comorbidities. All patients were treated with Medtronic’s CoreValve TAVI device.


Roy et al stated that TAVI in patients without aortic valve calcification could be made “more difficult by the lack of fluoroscopic landmarks to outline the annulus position and root anatomy.” They added that using fixed landmarks in the thoracic anatomy (ie, pacing wires) or using two pigtail catheters could help with the procedure.


Of the 42 patients actually implanted with the CoreValve device, eight required a second valve during the index procedure because of residual aortic regurgitation. After the procedure, 34 patients (including two patients who required a second valve) were classified as having grade I or lower regurgitation. Roy et al reported: “The Value Academic Research Consortium [VARC] was 74.4% when grade II or higher residual aortic regurgitation and the need for a second valve were taken into account.” They added that the 30-day mortality rate was 9.3% and the 30-day cardiovascular mortality was 2.3%, commenting: “The 12-month all-cause mortality rate was 21.4% (six of 28 patients) and the cardiovascular mortality rate was 10.7% (n=3).”


According to Roy et al, the stroke, vascular complications, bleeding, and mortality rates observed in their study compared “favourably” with published trials and registries for TAVI in patients with aortic stenosis. But, they added: “One would expect this to be so as patients with pure aortic regurgitation are younger with fewer comorbidities. Thus, although these results are encouraging for patients who are truly ineligible for surgery, surgical valve replacement remains the gold standard for those who can undergo it even at high risk.”


Concluding their study, Roy et al stated: “Despite the variation in causes of valvular regurgitation and complexity of patient anatomy, acceptable results in the high-risk group of patients can be achieved.” However, they added that the need for two valves and significant residual aortic regurgitation in this patient population remained “important considerations.”


Roy told Cardiovascular News: “TAVI for pure native aortic valve regurgitation is feasible for patients who are poor surgical candidates, but at present should not be considered in operable patients as surgery remains the gold standard. New generation TAVI devices that are repositionable, retrievable and anatomically orientated may be ideally suited for this indication and studies with these devices are needed.”