CHICAGO – Ten times as many papers were published on the mitral valve as were published on the tricuspid valve during the 1990s, based on a literature review.
Things have picked up over the past decade, however, for the “forgotten,” little-respected “Rodney Dangerfield” valve, with surgeons writing more about tricuspid regurgitation and doing more tricuspid surgery than ever before, Dr. Patrick McCarthy said at Heart Valve Summit 2014.
Dr. Patrick McCarthy
Tricuspid interventions more than doubled from 1999 to 2008, although overall hospital mortality was substantial at 10.6%. (J. Thorac. Cardiovasc. Surg. 2012;143:1043-9).
A Society of Thoracic Surgeons risk model containing intraoperative variables showed that multiple-valve surgery mortality is more than twice that of single-valve surgery, but that performance of arrhythmia ablation and atrioventricular valve repair are protective for mortality (Ann. Thorac. Surg. 2013;95:1484-90).
“There isn’t any data that the tricuspid per se is actually the reason that the operation is higher risk,” said Dr. McCarthy, director of the Bluhm Cardiovascular Institute and chief of cardiac surgery, Northwestern University in Chicago.
The new American Heart Association/American College of Cardiology (AHA/ACC) guideline on valvular heart disease, published earlier this year, reflects the changing attitudes about mitral valve surgery and the need for earlier intervention.
A class I indication for surgery remains in place for severe tricuspid regurgitation (TR) with mitral valve disease. However, what had been a class IIb indication in the 2006 guidelines for primary TR with symptoms is now a class I indication in the 2014 guidelines.
“Don’t wait for right ventricular failure in primary TR. Plan for earlier intervention, and think of it more like we do mitral regurgitation,” Dr. McCarthy said.
The recommendation for more moderate TR has also changed. The class IIb recommendation for patients with less than severe TR during mitral valve repair with pulmonary hypertension, right heart failure, or tricuspid dilation is now class IIa, indicating a lower threshold for surgery for these patients, he said.
Asymptomatic primary TR with right ventricle dilation or reoperations for TR with symptoms and prior left heart surgery had been a class III indication against surgery in 2006, but are now in sync with the European valvular guidelines with a class IIb indication, suggesting surgery may be considered.
The move toward earlier surgery is supported by results showing that TR only gets worse if left untreated, Dr. McCarthy said. Among patients with annular dilation greater than 70 mm as the only criterion for tricuspid valve repair (TVR), TR was shown to increase by more than 2 grades after 2 years in just 2% of patients who underwent TVR during mitral valve repair (MVR), versus 48% without TVR (Ann. Thorac. Surg. 2005;79:127-32).
Another study showed that prophylactic tricuspid annuloplasty in patients with dilated tricuspid annulus undergoing MVR reduces the rate of TR progression, improves right ventricular remodeling, and improves functional outcomes on the 6-minute walk test (J. Thorac. Cardiovasc. Surg. 2012;143:632-8).
Not all data, however, have been viewed through the same lens, with the “Mayo Clinic and Cleveland Clinic finding the same thing but drawing different conclusions,” Dr. McCarthy observed.
A Cleveland Clinic analysis involving 1,833 patients with degenerative mitral valve disease reported that MVR alone improved TR and right ventricular function in patients with severe TR (grade 3+/4+), but that improvements were incomplete and temporary. In contrast, MVR with concomitant TVR eliminated severe TR and improved RV function toward normal, “supporting an aggressive approach to important functional tricuspid regurgitation” (J. Cardiovasc Surg. 2013;146:1126-32).
An 11-year review by the Mayo Clinic in Rochester, Minn., involving 699 patients with functional TR and degenerative mitral valve leaflet prolapse also showed that MVR alone significantly reduced TR within the first year in all patients and produced significant decreases until the third year in those with severe regurgitation. Only one patient required tricuspid reoperation 4.5 years after mitral repair. The authors argued for a selective approach to TR, concluding that “tricuspid valve surgery is rarely necessary for most patients undergoing repair of isolated mitral valve prolapse.”
“While both Cleveland and Mayo Clinic found that untreated TR persisted, Mayo interpreted the rare need for reoperation and no decrease in 5-year survival as evidence that it need not be repaired, while Cleveland suggested with the evidence of improved RV function that it should be repaired,” Dr. McCarthy said in an interview. “The European Society of Cardiology and AHA/ACC guidelines would support the approach from the Cleveland Clinic.”
Dr. McCarthy disclosed inventing the Edwards MC3 tricuspid valve repair ring.