Optical Coherence Tomography in the Assessment and Management of Cardiac Allograft Vasculopathy.

PURPOSE OF REVIEW: Cardiac Allograft vasculopathy (CAV) is a major barrier to improving outcomes after heart transplantation. Coronary angiography has very low sensitivity to detect early CAV and intravascular ultrasound (IVUS) only improves it to some extent. In this article, we detail the current evidence surrounding use of Optical Coherence tomography (OCT) in patients with CAV. RECENT FINDINGS: OCT has the ability to recognize CAV at earlier stages with intimal thickness < 150 µm, can characterize CAV in almost pathologic / microscopic detail - plaque characteristics are better visualized and novel early features such as layered fibrotic plaques and microchannels have been identified. Progression of CAV can be monitored also, with promise shown in automated serial measurements also. OCT has significantly advanced our understanding of the pathophysiology-as well as permits precise monitoring and surveillance of the disease. Potential treatment options could also be evaluated using OCT.

Increased disparities in waitlist and post-heart transplantation outcomes according to socioeconomic status with the new heart transplant allocation system.

BACKGROUND: The study objective was to assess disparities in outcomes in the waitlist and post-heart transplantation (HT) according to socioeconomic status (SES) in the old and new U.S. HT allocation systems. METHODS: Adult HT candidates in the United Network for Organ Sharing database from 2014 through 2021 were included. Old or new system classification was according to listing before or after October 18, 2018. SES was stratified by patient ZIP code and median household income via U.S. Census Bureau and classified into terciles. Competing waitlist outcomes and post-transplantation survival were compared between systems. RESULTS: In total, 26,450 patients were included. Waitlisted candidates with low SES were more frequently younger, female, African American, and with higher body mass index. Reduced cumulative incidence (CI) of HT in the old system occurred in low SES (53.5%) compared to middle (55.7%, p = 0.046), and high (57.9%, p < 0.001). In the new system, the CI of HT was 65.3% in the low SES vs middle (67.6%, p = 0.002) and high (70.2%, p < 0.001), and SES remained significant in the adjusted analysis. In the old system, CI of death/delisting was similar across SES. In the new system, low SES had increased CI of death/delisting (7.4%) vs middle (6%, p = 0.012) and high (5.4%, p = 0.002). The old system showed similar 1-year survival across SES. In the new system, recipients with low SES had decreased 1-year survival (p = 0.041). CONCLUSIONS: SES affects waitlist and post-transplant outcomes. In the new system, all SES had increased access to HT; however, low SES had increased death/delisting due to worsening clinical status and decreased post-transplant survival.

Performance of Noninvasive Assessment in the Diagnosis of Right Heart Failure After Left Ventricular Assist Device.

Right heart failure (RHF) after left ventricular assist device (LVAD) is associated with poor outcomes. Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) defines RHF as elevated right atrial pressure (RAP) plus venous congestion. The purpose of this study was to examine the diagnostic performance of the noninvasive Intermacs criteria using RAP as the gold standard. We analyzed 108 patients with LVAD who underwent 341 right heart catheterizations (RHC) between January 1, 2006, and December 31, 2013. Physical exam, echocardiography, and laboratory data at the time of RHC were collected. Conventional two-by-two tables were used and missing data were excluded. The noninvasive Intermacs definition of RHF is 32% sensitive (95% cardiac index (CI), 0.21-0.44) and 97% specific (95% CI, 0.95-0.99) for identifying elevated RAP. Clinical assessment failed to identify two-thirds of LVAD patients with RAP > 16 mm Hg. More than half of patients with elevated RAP did not have venous congestion, which may represent a physiologic opportunity to mitigate the progression of disease before end-organ damage occurs. One-quarter of patients who met the noninvasive definition of RHF did not actually have elevated RAP, potentially exposing patients to unnecessary therapies. In practice, if any component of the Intermacs definition is present or equivocal, our data suggest RHC is warranted to establish the diagnosis.

Assessment and management of right ventricular failure in left ventricular assist device patients.

Mechanical circulatory support devices, including ventricular assist devices (VADs) and the total artificial heart, have evolved to become accepted therapeutic options for patients with severe congestive heart failure. Continuous-flow left VADs are the most prevalent option for mechanical circulatory assistance and reliably provide years of support. However, problems related to acute and chronic right heart failure in patients with left VADs continue to cause important mortality and morbidity. This review discusses the assessment and management of right ventricular failure in left VAD patients. The goal is to summarize current knowledge and suggest new approaches to managing this problem.

Use of gated cardiac computed tomography angiography in the assessment of left ventricular assist device dysfunction.

The purpose of this study is to describe the utility and limitations of gated contrast-enhanced cardiac computed tomography angiography in assessing left ventricular assist device function. Computed tomography angiography (CTA) was used in 14 patients with left ventricular assist devices (LVADs) who had persistent heart failure symptoms, hemodynamic instability, or potential problems with LVAD flows. Retrospectively gated contrast-enhanced CTA was performed on 64-detector scanner, and the CTA images were postprocessed in multiple curved projections on TeraRecon workstation. This study describes the use of CTA to identify LVAD-related issues that altered clinical management and explores the role of CTA and other techniques in evaluating LVAD function. Six of 14 LVAD patients who demonstrated no abnormality on CTA remained stable with medical management. In the remaining eight patients, CTA was abnormal, including abnormalities specifically related to the LVAD cannula. As a result of findings detected by CTA, six patients underwent surgical intervention, including device exchange and heart transplant. Computed tomography angiography is a noninvasive method that enhances diagnostic evaluation of patients with suspected LVAD dysfunction and can lead to changes in patient management.