Defining hospitalizations
One of the surgeons’ biggest concerns is that VARC-3 now defines hospitalization or rehospitalization as “any admission after the index hospitalization or study enrollment” for at least 24 hours, including an ED stay.
VARC-2 and SURTAVI defined hospitalizations as those for valve-related symptoms or worsening heart failure, whereas the newly reformulated definition of hospitalization was part of the main composite endpoint in the PARTNER-3 trial, along with stroke and mortality, that drove the superiority of TAVR over SAVR at 1 year for low-risk patients, Dr. Dayan noted.
“It’s not uncommon for patients who have cardiac surgery to come back for issues related to wound healing or mild pulmonary edema for a day or 2, and if you include these hospitalizations in the primary endpoint, it will dilute the real benefit of SAVR versus TAVR, which is mortality and stroke,” he added.
In choosing the broader definition, Dr. Généreux said they borrowed from heart failure studies that take a granular approach and account for every hospitalization, be it for a medication change or adjustment. “We cannot pick and choose which hospitalization we are going to consider or ignore.”
VARC-3 proposes criteria for identifying and diagnosing hypoattenuated leaflet thickening (HALT) and reduced leaflet motion and features a detailed chart of the new classification scheme for bioprosthetic valve dysfunction and failure.
Bioprosthetic valve dysfunction includes structural valve deterioration, nonstructural valve dysfunction (including abnormalities not intrinsic to the valve such as paravalvular regurgitation or prosthesis-patient mismatch), thrombosis, and endocarditis. VARC-3 proposes a five-class grading system for paravalvular regurgitation (mild, mild-moderate, moderate, moderate-severe, severe).
The document updates what the authors called a “previously vague definition” of valve thrombosis proposed in 2011 to now include “clinically significant” prosthetic valve thrombosis. This requires clinical sequelae of a thromboembolic event (stroke, transient ischemic attack, retinal occlusion, or other evidence of thromboembolism) or worsening valve stenosis/regurgitation and either hemodynamic valve deterioration stage 2 or 3 or confirmatory imaging (CT evidence of HALT or transesophageal echocardiographic findings). In the absence of symptoms/clinical sequelae, valve thrombosis (subclinical) can be diagnosed if there is hemodynamic valve deterioration stage 3 and confirmatory imaging.
Bioprosthetic valve failure is divided into three stages, with stage 1 taking into account clinical factors along with valve dysfunction, stage 2 being reintervention, and stage 3 being valve-related death.
“For us, bioprosthesis valve failure is not only the need for reintervention, but it’s also mortality, it’s also a significant increase in gradient or the occurrence of paravalvular leak,” said Dr. Généreux, of the Morristown (N.J.) Medical Center. “So it’s much more clinical.”
Stroke, myocardial infarction
VARC-3 provides detailed definitions of neurologic events and, in an attempt to harmonize with the Neurologic Academic Research Consortium, recommends combining assessment of neurologic symptoms with tissue-based criteria (pathology or neuroimaging, ideally diffusion-weighted MRI) to define stroke and other central nervous system injury.
It also recommends that assessment be performed 30-90 days after a neurologic event and that assessment of neurologic deficits for cerebral embolic protection trials be performed by a neurologist.
VARC-3 endorses the fourth Universal Definition of Myocardial Infarction for MI types 1-3, 4B, and 4C.
For periprocedural MI after percutaneous coronary intervention (PCI), coronary bypass graft surgery, TAVR, and SAVR, however, it endorses the modified Society for Cardiovascular Angiography and Interventions and Academic Research Consortium-2 definition, which uses troponin or creatine kinase-MB thresholds.
“Given that most current and future studies related to AVR strategies will involve long-term follow-up, with patients frequently suffering from coronary artery disease, VARC-3 believes that these definitions will allow the most appropriate characterization and classification of types of MI occurring in this population,” the committee wrote.
The decision comes after last year’s controversy surrounding the Abbott-sponsored EXCEL trial, which used a modified version of the SCAI definition for periprocedural MI as part of its primary composite endpoint of death, stroke, and MI.
Initial reports showed nearly twice the rate of periprocedural MI with cardiac surgery as with PCI, but after a BBC investigation involving leaked data and an onslaught of criticism from surgeons, later results using the third universal definition showed surgery had the advantage.
The debacle frayed relations between surgeons and interventionalists and prompted EACTS to withdraw its support for treatment recommendations for left main coronary artery disease.
Dr. Dayan applauded VARC-3 for incorporating more detailed information on stroke and neurologic events, but said the use of the SCAI definition in the final published document is in “total disregard” to the controversy generated among surgeons and interventionalists.
“The main concern for surgeons is defining periprocedural MI just by biochemical definitions, without any additional criteria like ECG, angiographic,” he said. “This is totally new and goes against what surgeons have been advocating for years around EXCEL.”
Dr. Sádaba was troubled by the definitions of MI and hospitalization, but also questioned other changes, like lumping vascular complications together with access-related complications. “The sense is a lot of what they’ve put here favors one type of intervention over the other.”
Dr. Généreux reported receiving consultant fees from Abbott Vascular, Abiomed, Boston Scientific, Cardinal Health, Cardiovascular System, Edwards Lifesciences, Medtronic, Opsens, Siemens, SoundBite Medical Solutions, Sig.Num, Saranas, Teleflex, Tryton Medical, and has equity in Pi-Cardia, Sig.Num, SoundBite Medical Solutions, Saranas, and Puzzle Medical. Dr. Crea reported receiving personal fees from Novartis, Bristol-Myers Squibb, Amgen, and AstraZeneca, and is a member of the advisory board of GlyCardial Diagnostics. Dr. Dayan and Dr. Sádaba reported no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.