Multicenter Evaluation of Volumetric Intravascular Ultrasound Early After Heart Transplantation and Long-Term Prognosis

Abstract

<h3>Purpose</h3> Previous studies found an increase in maximal intimal thickness (MIT) ≥0.5 mm during the first year after heart transplantation (HTx), based on 3-7 select cross-sectional intravascular ultasound (IVUS) images, predicts outcome. Consensus recommendations advise against select image analysis and long vessel (40-50 mm) volumetric evaluation is preferred. However, the prognostic utility of such assessment in HTx is unclear. This study determined the relationship between long vessel volumetric IVUS evaluation early after HTx and long-term outcome. <h3>Methods</h3> HTx recipients from four institutions underwent IVUS at 12 weeks and one year post-HTx and long vessel volumetric IVUS evaluation was performed. All-cause mortality was the primary and major adverse cardiac events (MACE i.e. composite of cardiac death, re-HTx, myocardial infarction, heart failure or coronary revascularization) was the secondary endpoint. <h3>Results</h3> Of 243 HTx recipients (mean follow-up 8.1±3.1 years) those with Percent Atheroma Volume (PAV) increase ≥7.0% (absolute percentage units) had a significantly increased risk of all-cause mortality (34% vs 14%, p=0.01; adjusted hazard ratio (HR) 2.60 (95% CI 1.37-4.93, p<0.01)) and MACE (40% vs 21%, p=0.04; adjusted HR 1.99 (95% 1.15-3.45, p=0.01)). MIT increase ≥0.5 mm was not associated with increased risk of all-cause mortality or MACE. <h3>Conclusion</h3> With long-vessel IVUS analysis, PAV increase≥7.0% (absolute percentage units) during the first year post-HTx predicts subsequent all-cause mortality and MACE, whereas the previously established threshold of MIT increase ≥0.5 mm does not.