Everolimus Prevents Coronary Microvasculopathy in Heart Transplant Recipients With Normal Coronary Angiograms: An Anatomo-Functional Study

Coronary Flow Velocity Reserve by Echocardiography: Beyond Atherosclerotic Disease

Coronary flow velocity reserve (CFVR) is defined as the ratio between coronary flow velocity during maximal hyperemia and coronary flow at rest. Gold-standard techniques to measure CFVR are either invasive or require radiation and are therefore inappropriate for large-scale adoption. More than 30 years ago, echocardiography was demonstrated to be a reliable tool to assess CFVR, and its field of application rapidly expanded. Although initially validated to assess the hemodynamic relevance of a coronary stenosis, CFVR by echocardiography was later used to investigate coronary microcirculation. Microvascular dysfunction was detected in many different conditions, ranging from organ transplantation to inflammatory disorders and from metabolic diseases to cardiomyopathies. Moreover, it has been proven that CFVR by echocardiography not only detects coronary microvascular involvement but is also an effective prognostic factor that allows a precise risk stratification of the patients. In this review, we will summarize the many applications of CFVR by echocardiography, focusing on the coronary involvement of systemic diseases.

Long-Term Effects of the Replacement of Calcineurin Inhibitors With Everolimus and Mycophenolate in Patients With Calcineurin Inhibitor-Related Nephrotoxicity

BACKGROUND

There is little evidence on the long-term effects of calcineurin inhibitor (CNI) withdrawal and substitution with everolimus and mycophenolate mofetil in maintenance therapy of patients who have received heart transplants and have concurrent CNI nephrotoxicity. Aims of this study were to evaluate the progression of renal dysfunction after discontinuation of CNIs and to monitor for major adverse events after therapy change.

METHODS

Data from 41 patients who underwent heart transplant and have different degrees of renal dysfunction (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m²), without evidence of proteinuria, and in whom CNI therapy was replaced by everolimus, were analyzed. At the time of CNI withdrawal, clinical parameters, echocardiographic data, blood tests of renal function, and monitoring of adverse events were recorded. The median follow-up period was 5 years ± 28 months.

RESULTS

In 52% of patients, there was a clear improvement in renal function (10.5 mL/min/1.73 m² of extra eGFR on average). The former were characterized by less advanced age and a short time from the heart transplant. The echocardiographic parameters showed a significant reduction in septum thickness (11.58 ± 2 mm vs 10.29 ± 2 mm; P = .0001) and in left ventricle posterior wall thickness (10.74 ± 1 mm vs 9.74 ± 1 mm; P = .0004). The incidence of late acute rejection and cardiac allograft vasculopathy was similar in our population compared to literature data.

CONCLUSIONS

A therapeutic switch from CNIs to everolimus and mycophenolate mofetil can improve renal function in patients with CNI nephrotoxicity, especially in those with a shorter time period from transplantation, without exposing them to a higher incidence of late acute rejection and cardiac allograft vasculopathy.

The Landscape of Digital Pathology in Transplantation: From the Beginning to the Virtual E-Slide

Background

Digital pathology has progressed over the last two decades, with many clinical and nonclinical applications. Transplantation pathology is a highly specialized field in which the majority of practicing pathologists do not have sufficient expertise to handle critical needs. In this context, digital pathology has proven to be useful as it allows for timely access to expert second-opinion teleconsultation. The aim of this study was to review the experience of the application of digital pathology to the field of transplantation.

Methods

Papers on this topic were retrieved using PubMed as a search engine. Inclusion criteria were the presence of transplantation setting and the use of any type of digital image with or without the use of image analysis tools; the search was restricted to English language papers published in the 25 years until December 31, 2018.

Results

Literature regarding digital transplant pathology is mostly about the digital interpretation of posttransplant biopsies (75 vs. 19), with 15/75 (20%) articles focusing on agreement/reproducibility. Several papers concentrated on the correlation between biopsy features assessed by digital image analysis (DIA) and clinical outcome (45/75, 60%). Whole-slide imaging (WSI) only appeared in recent publications, starting from 2011 (13/75, 17.3%). Papers dealing with preimplantation biopsy are less numerous, the majority (13/19, 68.4%) of which focus on diagnostic agreement between digital microscopy and light microscopy (LM), with WSI technology being used in only a small quota of papers (4/19, 21.1%).

Conclusions

Overall, published studies show good concordance between digital microscopy and LM modalities for diagnosis. DIA has the potential to increase diagnostic reproducibility and facilitate the identification and quantification of histological parameters. Thus, with advancing technology such as faster scanning times, better image resolution, and novel image algorithms, it is likely that WSI will eventually replace LM.