Primary graft dysfunction does not lead to increased cardiac allograft vasculopathy in surviving patients

Recurrent acute cellular rejection graded ISHLT 1R early after heart transplantation negatively affects long-term outcomes: The prognostic significance of 1990 ISHLT grades 1B and 2

PURPOSE

We investigated the implications of early recurrent 1R rejections for long-term outcomes after heart transplantation (HT) and evaluated the prognostic significance of 1990 ISHLT grading 1B/2 versus 1A.

METHODS

Data on all patients who underwent HT between 1992 and 2017 were reviewed. Patients with ≥2 endomyocardial biopsies graded 1R in the first 3 months were classified as "recurrent 1R." Those patients were further categorized according to 1A vs. 1B/2. Outcomes (>3 months) were long-term rejections and the combined endpoint of cardiac allograft vasculopathy (CAV) and cardiovascular (CV) mortality.

RESULTS

Sixty-nine out of 228 patients were classified as recurrent grade 1R. In the recurrent 1R group, 2R rejection rate was significantly higher (2.6 ± 0.6 vs 1.2 ± 0.4, p = 0.03), while survival free of rejections was lower (5-year: 57.1% vs. 72.3%, p = 0.022). Multivariate analysis showed that early recurrent 1R rejection was associated with a 30% increased risk for subsequent major rejection. Among 28 patients classified as 1B/2 of the recurrent group, rejection scores were higher, while survival free of rejections was lower, compared to 37 patients of the recurrent group classified as 1A (5-year: 57.1% vs. 72.7%, p = 0.013). Kaplan-Meier analysis showed that CAV/CV mortality at 10 years of follow-up was significantly higher among the recurrent 1R group (38% vs. 18% p < 0.05). Multivariate analysis showed that early recurrent 1R rejections were associated with a 2.5-fold increased risk for CAV/CV mortality.

CONCLUSION

Early recurrent grade 1R rejections negatively affect long-term outcomes. The adverse outcomes are experienced mainly by 1R patients subcategorized as1B/2 and not 1A.

Short- and Long-Term Outcomes of Live Donor Renal Allografts From Older and Younger Donors

BACKGROUND

The rising demand for living renal donors has led to the recruitment of older donors. Findings vary, but these grafts appear to survive as long as grafts from standard criteria deceased and expanded criteria deceased donors. We investigated the effects of donor age ≥65 years and the presence or absence of donor antihypertensive therapy on patient condition 1 year after transplantation, and retrospectively examined 1-year (273 patients), 3-year (217 patients), and 5-year (140 patients) patient and graft survival.

METHODS

We divided 273 donor-recipient pairs into Group Y (donor age <65 years, n = 224) and Group O (donor age ≥65 years, n = 49). Group O was subdivided into donors receiving treatment for hypertension (subgroup O-1, n = 16) and those not receiving treatment for hypertension (subgroup O-2, n = 33). We compared results of 1 hour post-transplant biopsies and looked at a small number of 1 year post-transplant biopsies.

RESULTS

Although a significantly larger percentage of recipients from younger donors were undergoing preemptive transplantation, and the incidence of arteriosclerosis was significantly higher in the Group O kidneys, there were no significant differences between the 2 groups in terms of patient or graft survival at 1, 3, or 5 years; serum creatinine levels; or number of episodes of acute rejection. The presence or absence of donor antihypertensive treatment had no effect.

CONCLUSIONS

We found that donor age ≥65, with or without antihypertensive treatment, had no effect on graft or patient survival.

Postoperative management of heart transplantation patients

Heart transplant recipients are at risk for a number of post-transplantation complications such as graft dysfunction, rejection, and infection. The rates of many complications are decreasing over time, and prognosis is improving. However, these patients continue to experience significant morbidity and mortality. This review focuses on the optimal management of heart transplant recipients in the postoperative period, based on current knowledge. More information is needed about the best ways to predict, prevent, and treat primary graft dysfunction, right ventricular failure, and cellular and antibody-mediated rejection.

Interacting mechanisms in the pathogenesis of cardiac allograft vasculopathy

Cardiac allograft vasculopathy is the major cause of late graft loss in heart transplant recipients. Histological studies of characteristic end-stage lesions reveal arterial changes consisting of a diffuse, confluent, and concentric intimal expansion containing graft-derived cells expressing smooth muscle markers, extracellular matrix, penetrating microvessels, and a host mononuclear cell infiltrate concentrated subjacent to an intact graft-derived luminal endothelial cell lining with little evidence of acute injury. This intimal expansion combined with inadequate compensatory outward remodeling produces severe generalized stenosis extending throughout the epicardial and intramyocardial arterial tree that causes ischemic graft failure. Cardiac allograft vasculopathy lesions affect ≥50% of transplant recipients and are both progressive and refractory to treatment, resulting in ≈5% graft loss per year through the first 10 years after transplant. Lesions typically stop at the suture line, implicating alloimmunity as the primary driver, but pathogenesis may be multifactorial. Here, we will discuss 6 potential contributors to lesion formation (1) conventional risk factors of atherosclerosis; (2) pre- or peritransplant injuries; (3) infection; (4) innate immunity; (5) T-cell-mediated immunity; and (6) B-cell-mediated immunity through production of donor-specific antibody. Finally, we will consider how these various mechanisms may interact with each other.