麻豆传媒

SAN ANTONIO -- In response to the opioid epidemic, a primer to treating infective endocarditis (IE) specifically related to drug use was released by the Society of Thoracic Surgeons (STS).

A workforce on the surgical management of tricuspid endocarditis in patients who inject drugs cautioned against relying on vegetation size and microbiology as criteria for surgery in these patients. Also addressed are the ethics of performing multiple redo surgeries in drug users and transcatheter debulking (TCD).

"Intensive treatment for IE, including antimicrobials and surgery, is neither effective nor advantageous without targeting the underlying substance abuse disorder," said workforce representative Joshua Goldberg, MD, of Weill Cornell Medicine/NewYork-Presbyterian Hospital in New York City, here at the STS annual meeting. "Source control of substance abuse disorder is equally important as source control of the infection," he stressed.

The statement comes during the time of a documented rise in the incidence of tricuspid valve surgeries for endocarditis, in step with the opioid epidemic of recent years.

Session co-moderator Kendra Grubb, MD, MHA, of Emory University in Atlanta, remarked on the ethical challenges in managing these patients with a substance use disorder they may or may not ever overcome. When she asked fellow panelists if they offer drug users a second chance at surgery, Goldberg said yes without hesitation.

"I've done four for a recurrent user," he said. "It's kind of ridiculous but at the same time, how many redo [coronary artery bypass graft surgeries] would one do if someone's diabetic or smoking?"

Also saying yes to a second chance was session co-moderator Mark Slaughter, MD, of University of Louisville, Kentucky.

"We give them one more time," Slaughter said. However, he noted that the rate of recidivism at his institution has reached the point where they can only follow up on 46% of patients -- meaning most died or disappeared even after successful treatment. "It's difficult to get long-term data on this population," he lamented.

Limited Evidence on Vegetation Size, Microbiology, Optimal Approach

Goldberg emphasized the meager data on surgery for drug use-associated tricuspid valve endocarditis, with most societal recommendations extrapolated from the literature on left-sided endocarditis and people who do not inject drugs. He cited, for example, the 2023 European guidelines on endocarditis that give a class I-C recommendation for surgery in patients with right-sided infective endocarditis who have large residual tricuspid vegetations (>20 mm) with recurrent septic pulmonary emboli on appropriate antibiotics.

Yet Goldberg and colleagues warned operators against basing the decision to do tricuspid valve surgery on vegetation size alone, as it hasn't been proven that increasing vegetation size causes adverse outcomes in these patients. Vegetation size without infectious burden (i.e., bacteremia, sepsis, or severe right ventricular failure) is not clearly associated with better outcomes, either, he said.

Similarly, he said that microbiological criteria for endocarditis surgery are poorly supported by evidence, being again extrapolated from the left-side literature. Tricuspid surgery should not be mandatory just because of specific organisms unless there are local or systemic manifestations such as persistent bacteremia, sepsis, or heart failure, he said, adding that persistent bacteremia may indicate uncontrolled metastatic infection independent of valvular involvement, such as septic emboli and injection site infections.

As for the specific surgical approach, Goldberg said that depends on the extent of endocarditis damage, but tricuspid valve repair is usually preferred over replacement in people who inject drugs. Outright removal of the valve is the least favorable surgical approach but may be considered in very select patients.

Goldberg mentioned TCD to reduce the vegetation burden, the goal of this being to improve antibiotic penetrance and decrease septic emboli. TCD has rapidly gained traction in recent years but is still in its infancy. More research is needed to determine the safety and efficacy of TCD in patients with drug-use associated tricuspid valve endocarditis, he said.

Nonetheless, he emphasized that any surgeon who does endocarditis surgery should be learning TCD as it is easy, and passing this off to other specialties such as interventional radiology and cardiology "is a shame."

Transcatheter Suction Debulking Outcomes at Emory

One center's early experience with TCD suggested it was safe but left behind lingering tricuspid disease requiring subsequent reintervention, according to research presented during the same session at STS.

In-hospital complications tended to be lower after suction debulking compared with tricuspid valve surgery, though patients were more likely to be left with moderate or worse tricuspid regurgitation (TR; 75% vs 3%) and need reintervention (25% vs 3%), reported Hiroki Ueyama, MD, a cardiology research fellow also at Emory.

His group conducted a small retrospective study in people with isolated tricuspid valve IE, 16 of whom had AngioVac suction debulking done and 29 who got conventional surgery. Data on midterm outcomes averaging 473 days out detected few differences in clinical outcomes between the two approaches except for reinterventions:

• All-cause readmissions: 50 readmissions for the 16 TCD patients vs 35 readmissions for 29 surgical patients (P=0.48)
• Recurrent IE: 38 cases vs 17 cases (P=0.25)
• Need for reintervention: 50 reinterventions vs 17 reinterventions (P=0.048)
• All-cause mortality: 13 deaths vs 10 deaths (P=1.0)

Ueyama noted that half of reinterventions in the suction debulking cohort occurred in the same stay, mostly due to significant TR and, in one case, persistent bacteremia.

At any rate, his institution has already shifted to a majority-suction debulking approach.

"Suction debulking may be considered as initial therapy with surgery reserved in cases with insufficient debulking or severe valvular destruction," Ueyama said. "Suction debulking may be considered as a bridge to surgery offering a chance to address addiction or achieve medical stabilization" while reducing "lifetime occurrence of sternotomy and thoracotomy."

Grubb agreed and said that the focus shouldn't be on TR in these patients. "The majority are not dying from TR, they're dying from drug addiction. AngioVac gets them to the point of treatment for addiction so they can come back for the right treatment for TR," she said.

"[TCD] should be part of your armamentarium, used in appropriately selected patients," Slaughter said.

For their study, Ueyama and colleagues compared suction debulking using partial venovenous bypass with the AngioVac device vs conventional tricuspid valve surgery. From 2010 to 2022, there were 45 patients identified for the study after excluding people who underwent concomitant cardiac surgery.

Ueyama noted that all patients received general anesthesia with transesophageal echocardiography and fluoroscopic guidance for the AngioVac procedure.

Surgery consisted of tricuspid valve replacement in 93% of cases and repair in the remaining 7%.

Overall, patients had a median age around 37 years. The proportion with prior IE was 31% in the suction debulking group and 52% in the surgical group. Severe TR was noted in 19% and 49%, respectively, for a significant between-group difference at baseline. Approximately 40% of people had septic shock in both groups.

Ueyama acknowledged that information about people who had tricuspid IE managed medically was not in their database and therefore not available for comparison.

Study senior author William Brent Keeling, MD, also of Emory, added that the investigators have not analyzed cost either, as this is "an evolving area" that "needs to be pursued further."