Association Between Vegetation Size and Outcome in the Partial Oral Antibiotic Endocarditis Treatment Trial.

Step-down oral antibiotic therapy is associated with a non-inferior long-term outcome compared with continued intravenous antibiotic therapy in the treatment of left-sided infective endocarditis. We aimed to analyze whether step-down oral therapy compared with continued intravenous antibiotic therapy is also associated with a non-inferior outcome in patients with large vegetations (vegetation length ≥ 10 mm) or among patients who underwent surgery before step-down oral therapy. We included patients without presence of aortic root abscess at diagnosis from the POET (Partial Oral Antibiotic Endocarditis Treatment) study. Multivariable Cox regression analyses were used to find associations between large vegetation, cardiac surgery, step-down oral therapy, and the primary end point (composite of all-cause mortality, unplanned cardiac surgery, embolic event, or relapse of positive blood cultures during follow-up). A total of 368 patients (age 68 ± 12, 77% men) were included. Patients with large vegetations (n = 124) were more likely to undergo surgery compared with patients with small vegetations (n = 244) (65% vs 20%, p <0.001). During a median 1,406 days of follow-up, 146 patients reached the primary end point. Large vegetations were not associated with the primary end point (hazard ratio 0.74, 95% confidence interval 0.47 to 1.18, p = 0.21). Step-down oral therapy was non-inferior to continued intravenous antibiotic in all subgroups when stratified by the presence of a large vegetation at baseline and early cardiac surgery. Step-down oral therapy is safe in the presence of a large vegetation at diagnosis and among patients who underwent early cardiac surgery.

The importance of nonobstructive plaque characteristics in symptomatic and asymptomatic coronary artery disease.

BACKGROUND: We examined obstructive and nonobstructive plaque volumes in populations with subclinical and clinically manifested coronary artery disease (CAD) using quantitative computed tomography (QCT). METHODS: 855 participants with CAD (274 asymptomatic individuals, 254 acute chest pain patients without acute coronary syndrome (ACS), and 327 patients with ACS) underwent QCT of proximal coronary segments to assess participant-level plaque volumes of dense calcium, fibrous, fibrofatty, and necrotic core tissue. RESULTS: Nonobstructive (<50% stenosis) plaque volumes were greater than obstructive plaque volumes, irrespective of population (all p<0.0001): Asymptomatic individuals (mean (95% CI)): 218 [190-250] vs. 16 [12-22] mm3; acute chest pain patients without ACS: 300 [263-341] vs. 51 [41-62] mm3; patients with ACS: 370 [332-412] vs. 159 [139-182] mm3. After multivariable adjustment, nonobstructive fibrous and fibrofatty tissue volumes were greater in acute chest pain patients without ACS compared to asymptomatic individuals (fibrous tissue: 122 [107-139] vs. 175 [155-197] mm3, p<0.01; fibrofatty tissue: 44 [38-50] vs. 71 [63-80] mm3, p<0.01. Necrotic core tissue was greater in ACS patients (29 [26-33] mm3) compared to both asymptomatic individuals (15 [13-18] mm3, p<0.0001) and acute chest pain patients without ACS (21 [18-24] mm3, p<0.05). Nonobstructive dense calcium volumes did not differ between the three populations: 29 [24-36], 29 [23-35], and 41 [34-48] mm3, p>0.3 respectively. CONCLUSION: Nonobstructive CAD was the predominant contributor to total atherosclerotic plaque volume in both subclinical and clinically manifested CAD. Nonobstructive fibrous, fibrofatty and necrotic core tissue volumes increased with worsening clinical presentation, while nonobstructive dense calcium tissue volumes did not.