Physicians who perform a variety of device implant procedures face a difficult choice in determining whether a patient should be treated. A new article in the Journal of the American College of Cardiology (JACC) recommends that patients who ordinarily would be candidates for surgical aortic valve replacement (SAVR) might instead be referred for the transcatheter alternative. However, the authors also said, “Mitraclip cases should generally be avoided” aside from a few instances. The net effect would be to significantly suppress utilization for the duration of a pandemic that brings with it an uncertain expiration date.
The article, which is in press in JACC, points to a susceptibility to the SARS-CoV-2 virus among those who suffer from underlying cardiovascular disease, although these patients are also at risk of poorer outcomes after infection. Among the cardiac complications of COVID-19 are biventricular heart failure and “malignant arrhythmias,” and the objective in drafting the “crisis-driven” recommendations is to treat patients appropriately without creating undue exposure to the virus.
Triage if outcomes unaffected over two to three months
One of the recommendations is to avoid any care that would not “directly impact clinical care or outcomes” in the next two to three months, a list that includes treatment of patent foramen ovale and atrial septal defect. Among the devices that would be affected by this recommendation are products from Abbott Laboratories, of Abbott Park, Ill., whose structural heart division is headquartered in Santa Clara, Calif. Another company that is likely to take a hit on volumes is W.L. Gore & Associates Inc., of Flagstaff, Ariz., whose Cardioform occluder won an FDA nod in June 2019.
In contrast, patients with severe aortic stenosis with cardiogenic shock would present the physician with a clear-cut argument for treatment and possible admission. The problem for these patients is that the poor hemodynamic performance of the aorta threatens multiple organs enough to raise the prospect of single or even multiple organ failure. The authors said severe mitral valve regurgitation with refractory heart failure also might fall into this category.
Among the aortic stenosis patients who would be candidates for immediate admission and/or treatment (tier 1 patients) are those who might suffer from decompensation, such as aortic stenosis patients with recurrent syncope. The authors also said this group of patients should be treated during hospitalization or within a week of diagnosis, although some aortic and mitral valve patients “can be triaged for treatment over the subsequent months.” The authors added that triage can be handled via telemedicine. This recommendation is more likely to be followed, given recent expansions of Medicare telemedicine coverage.
Tier 2 patients, including those with severe aortic stenosis with rapidly progressive or worsening stage III heart failure symptoms, would have to be monitored “at weekly intervals,” and the intervention might wait as long as two months. Tier 3 patients for aortic stenosis would be subject to a postponement of at least two months, despite suffering from severe stenosis and symptoms of class I or II heart failure. Patients with severe tricuspid regurgitation also would fall into tier 3, assuming their stage II/III heart failure symptoms are being managed via medical therapy.
The two major companies in the U.S. with a substantial footprint in the aortic valve replacement space are Edwards Lifesciences Inc., of Irvine, Calif., and Dublin-based Medtronic plc. They are on the third iteration of their transcatheter aortic valve replacement (TAVR) devices, both of which have been approved by the U.S. FDA for patients at low risk of poor surgical outcomes.
On the other hand, Jenavalve Technologies Inc., of Irvine, Calif., won a breakthrough device designation at the beginning of this year, although the company indicated that it would not seek a humanitarian device exemption until the second half of 2020. Boston Scientific Corp., of Marlborough, Mass., is positioned in the TAVR market with its Lotus Edge device, although that approval is for high-risk patients only. That suggests that sales of the Lotus might not be as affected by the pandemic as the Edwards and Medtronic units.
There is more than one technology in the med-tech space for mitral valve regurgitation, including Abbott’s Tendyne for mitral valve replacement. The device snared a CE mark at the beginning of 2020 and is indicated for mitral valves that are beyond repair. This device is not approved in the U.S., however, although the Mitraclip registered global sales of roughly $700 million last year. The FDA only recently gave Abbott the go-ahead to study the Mitraclip in patients at moderate surgical risk, and thus the impact on sales of the device will not be as severe as might otherwise be the case.
The authors noted that patient fear of exposure to the SARS-CoV-2 virus still may be driving reluctance, even among those with ST segment-elevated infarct.
The choice of TAVR vs. SAVR may be dictated to some extent by occupancy rates in intensive care units. However, patients with “reasonable anatomy” also might be referred for TAVR over SAVR in this predicament. This is particularly so when the aortic stenosis patient presents with a low risk of surgical complications and a low risk for pacemaker need.