Prognostic value of comprehensive intracoronary physiology assessment early after heart transplantation.

AIMS: We evaluated the long-term prognostic value of invasively assessing coronary physiology after heart transplantation in a large multicentre registry. METHODS AND RESULTS: Comprehensive intracoronary physiology assessment measuring fractional flow reserve (FFR), the index of microcirculatory resistance (IMR), and coronary flow reserve (CFR) was performed in 254 patients at baseline (a median of 7.2 weeks) and in 240 patients at 1 year after transplantation (199 patients had both baseline and 1-year measurement). Patients were classified into those with normal physiology, reduced FFR (FFR ≤ 0.80), and microvascular dysfunction (either IMR ≥ 25 or CFR ≤ 2.0 with FFR > 0.80). The primary outcome was the composite of death or re-transplantation at 10 years. At baseline, 5.5% had reduced FFR; 36.6% had microvascular dysfunction. Baseline reduced FFR [adjusted hazard ratio (aHR) 2.33, 95% confidence interval (CI) 0.88-6.15; P = 0.088] and microvascular dysfunction (aHR 0.88, 95% CI 0.44-1.79; P = 0.73) were not predictors of death and re-transplantation at 10 years. At 1 year, 5.0% had reduced FFR; 23.8% had microvascular dysfunction. One-year reduced FFR (aHR 2.98, 95% CI 1.13-7.87; P = 0.028) and microvascular dysfunction (aHR 2.33, 95% CI 1.19-4.59; P = 0.015) were associated with significantly increased risk of death or re-transplantation at 10 years. Invasive measures of coronary physiology improved the prognostic performance of clinical variables (χ2 improvement: 7.41, P = 0.006). However, intravascular ultrasound-derived changes in maximal intimal thickness were not predictive of outcomes. CONCLUSION: Abnormal coronary physiology 1 year after heart transplantation was common and was a significant predictor of death or re-transplantation at 10 years.

Patient perceptions of the re-usable Respimatt® Soft Mist™ inhaler in current users and those switching to the device: A real-world, non-interventional COPD study.

PLAIN LANGUAGE SUMMARY: Inhalers are often used to treat patients with chronic obstructive pulmonary disease (COPD). However, there are many available, which can lead to confusion and poor inhaler technique. It is important for a patient to be happy with their inhaler. This study looked at how patients liked the re-usable Respimat® Soft Mist™ inhaler vs. their previous inhaler. It also asked whether they would be willing to continue using the device at the end of the study period.After 4-6 weeks of using the re-usable device, patients reported that they were happy with the inhaler and most would be willing to carry on using it.Overall, these results show that doctors can prescribe Respimat re-usable to patients, even if the patient has not used the inhaler before.

Invasive haemodynamics in de novo everolimus vs. calcineurin inhibitor heart transplant recipients.

AIMS: Invasive haemodynamic profiles at rest and during exercise after heart transplantation (HTx) have never been described in a randomized trial where de novo everolimus (EVR)-based therapy with early calcineurin inhibitor (CNI) withdrawal has been compared with conventional CNI treatment. We report central invasive haemodynamic parameters at rest and exercise during a 3 year follow-up after HTx in a sub-study of the SCandiavian Heart transplant Everolimus De novo stUdy with earLy calcineurin inhibitor avoidancE trial. We hypothesized that the nephroprotective properties, the less development of cardiac allograft vasculopathy (CAV), and the antifibrotic properties of EVR, in comparison with CNI-based immunosuppression, would demonstrate favourable invasive haemodynamic profiles in patients at rest and during exercise. METHODS AND RESULTS: Ninety of 115 HTx recipients randomized to EVR or CNI treatment performed right heart catheterization at rest and 68 performed right heart catheterization at exercise up to 3 years after HTx. Haemodynamic profiles were compared between EVR and CNI treatment groups. Resting haemodynamics improved in both groups from pre-HTx to the first follow-up at 7-11 weeks post-HTx and thereafter remained unchanged up to 3 years of follow-up. During follow-up, cardiac reserve during exercise increased with higher levels of maximum heart rate (118 to 148 b.p.m., P < 0.001), mean arterial pressure (103 to 128 mmHg, P < 0.001), and cardiac output (10.3 to 12.2 l/min, P < 0.001). No significant differences in haemodynamic parameters were observed between the EVR and CNI groups at rest or exercise. Isolated post-capillary pulmonary hypertension (mean pulmonary arterial pressure > 20 mmHg, pulmonary arterial wedge pressure ≥ 15 mmHg, and pulmonary vascular resistance <3) were measured in 11% of the patients at 7-11 weeks, 5% at 12 months, and 6% at 36 months after HTx. The EVR group had significantly better kidney function (76 mL/min/1 vs. 60 mL/min/1, P < 0.001) and reduced CAV (P < 0.01) but an increased rate of early biopsy-proven treated rejections (21.2% vs 5.7%, P < 0.01) compared with the CNI group at any time point. The differences in renal function, CAV, or early biopsy-proven treated acute rejections were not associated with altered haemodynamics. CONCLUSIONS: De novo EVR treatment with early CNI withdrawal compared with conventional CNI therapy did not result in differences in haemodynamics at rest or during exercise up to 3 years after HTx despite significant differences in renal function, reduced CAV, and number of early biopsy-proven treated rejections.

Mild acute cellular rejection and development of cardiac allograft vasculopathy assessed by intravascular ultrasound and coronary angiography in heart transplant recipients-a SCHEDULE trial substudy.

To evaluate the association between mild acute cellular rejection (ACR) and the development of cardiac allograft vasculopathy (CAV) after heart transplantation (HTx). Substudy of the SCHEDULE trial (n = 115), where de novo HTx recipients were randomized to (i) everolimus with early CNI elimination or (ii) CNI-based immunosuppression. Seventy-six patients (66%) were included based on matched intravascular ultrasound (IVUS) examinations at baseline and year 3 post-HTx. Biopsy-proven ACR within year 1 post-HTx was recorded and graded (1R, 2R, 3R). Development of CAV was assessed by IVUS and coronary angiography at year 3 post-HTx. Median age was 53 years (45-61), and 71% were male. ACR was recorded in 67%, and patients were grouped by rejection profile: no ACR (33%), only 1R (42%), and ≥2R (25%). Median ∆MIT (maximal intimal thickness)BL-3Y was not significantly different between groups (P = 0.84). The incidence of CAV was 49% by IVUS and 26% by coronary angiography with no significant differences between groups. No correlation was found between number of 1R and ∆MITBL-3Y (r = -0.025, P = 0.83). The number of 1R was not a significant predictor of ∆MITBL-3Y (P = 0.58), and no significant interaction with treatment was found (P = 0.98). The burden of mild ACR was not associated with CAV development.

Everolimus Initiation With Early Calcineurin Inhibitor Withdrawal in De Novo Heart Transplant Recipients: Long-term Follow-up From the Randomized SCHEDULE Study.

BACKGROUND: A calcineurin inhibitor (CNI)-free immunosuppressive regimen has been demonstrated to improve renal function early after heart transplantation, but long-term outcome of such a strategy has not been well described. METHODS: In the randomized SCHEDULE trial, de novo heart transplant recipients received (1) everolimus with reduced-exposure CNI (cyclosporine) followed by CNI withdrawal at week 7-11 posttransplant or (2) standard-exposure cyclosporine, both with mycophenolate mofetil and corticosteroids; 95/115 randomized patients were followed up at 5-7 years posttransplant. RESULTS: Mean measured glomerular filtration rate was 74.7 mL/min and 62.4 mL/min with everolimus and CNI, respectively. The mean difference was in favor of everolimus by 11.8 mL/min in the intent-to-treat population (P = 0.004) and 17.2 mL/min in the per protocol population (n = 75; P < 0.001). From transplantation to last follow-up, the incidence of biopsy-proven acute rejection (BPAR) was 77% (37/48) and 66% (31/47) (P = 0.23) with treated BPAR in 50% and 23% (P < 0.01) in the everolimus and CNI groups, respectively; no episode led to hemodynamic compromise. Coronary allograft vasculopathy (CAV) assessed by coronary intravascular ultrasound was present in 53% (19/36) and 74% (26/35) of everolimus- and CNI-treated patients, respectively (P = 0.037). Graft dimensions and function were similar between the groups. Late adverse events were comparable. CONCLUSIONS: These results suggest that de novo heart transplant patients randomized to everolimus and low-dose CNI followed by CNI-free therapy maintain significantly better long-term renal function as well as significantly reduced CAV than patients randomized to standard CNI treatment. Increased BPAR in the everolimus group during year 1 did not impair long-term graft function.

The carnitine-butyrobetaine-TMAO pathway after cardiac transplant: Impact on cardiac allograft vasculopathy and acute rejection.

BACKGROUND: Alterations in the partly microbiota-dependent carnitine-γ-butyrobetaine (γBB)-trimethylamine N-oxide (TMAO) pathway have been linked to the progression of heart failure and atherosclerotic disease. We evaluated if circulating γBB, TMAO, and their common precursors carnitine and trimethyllysine (TML) were dysregulated after heart transplantation and associated with development of cardiac allograft vasculopathy (CAV) and acute rejection. METHODS: We measured these metabolites in plasma from heart transplant recipients with everolimus-based (n = 32) and standard cyclosporine-based immunosuppression (n = 30) at different time-points and accompanied by assessment of CAV by intravascular ultrasound. RESULTS: Baseline levels of carnitine, TMAO, and TML were elevated in heart transplant recipients compared with controls, and TML remained elevated throughout the observation period. The microbiota-dependent metabolite γBB increased steadily during 3 years of follow-up, with a similar decrease in its endogenous precursor TML. The increase in γBB and the change in TML were associated with a change in total atheroma volume from baseline to 3 years. Increases in γBB and carnitine levels from baseline to 1 year were associated with an increased frequency of acute rejection within the first year after heart transplant. CONCLUSIONS: Our study reveals alterations of the carnitine-γBB-TMAO pathway after heart transplant, with increasing levels of γBB being associated with acute rejection and increase in total atheroma volume during 3 years of follow-up. Future studies should clarify whether interactions between dietary factors, immunosuppressive drugs, and the gut microbiota could influence acute rejection and CAV development to delineate mechanisms and potential novel treatment targets.

Asymptomatic coronary artery disease in a Norwegian cohort with type 2 diabetes: a prospective angiographic study with intravascular ultrasound evaluation.

AIMS: The prevalence of asymptomatic coronary artery disease (CAD) in type 2 diabetes (T2D) is unclear. We investigated the extent and prevalence of asymptomatic CAD in T2D patients by utilizing invasive coronary angiography (ICA) and intravascular ultrasound (IVUS), and whether CAD progression, evaluated by ICA, could be modulated with a multi-intervention to reduce cardiovascular (CV) risk. METHODS: Fifty-six T2D patients with ≥ 1 additional CV risk factor participated in a 2 year randomized controlled study comparing hospital-based multi-intervention (multi, n = 30) versus standard care (stand, n = 26), with a pre-planned follow-up at year seven. They underwent ICA at baseline and both ICA and IVUS at year seven. ICA was described by conventional CAD severity and extent scores. IVUS was described by maximal intimal thickness (MIT), percent and total atheroma volume and compared with individuals without T2D and CAD (heart transplant donors who had IVUS performed 7-11 weeks post-transplant, n = 147). RESULTS: Despite CV risk reduction in multi after 2 years intervention, there was no between-group difference in the progression of CAD at year seven. Overall, the prevalence of CAD defined by MIT ≥ 0.5 mm in the T2DM subjects was 84%, and as compared to the non-T2DM controls there was a significantly higher atheroma burden (mean MIT, PAV and TAV in the T2D population were 0.75 ± 0.27 mm, 33.8 ± 9.8% and 277.0 ± 137.3 mm3 as compared to 0.41 ± 0.19 mm, 17.8 ± 7.3% and 134.9 ± 100.6 mm3 in the reference population). CONCLUSION: We demonstrated that a 2 year multi-intervention, despite improvement in CV risk factors, did not influence angiographic progression of CAD. Further, IVUS revealed that the prevalence of asymptomatic CAD in T2D patients is high, suggesting a need for a broader residual CV risk management using alternative approaches. Trial registration Clinical trials.gov id: NCT00133718 ( https://clinicaltrials.gov/ct2/show/NCT00133718 ).

Circulating delta-like Notch ligand 1 is correlated with cardiac allograft vasculopathy and suppressed in heart transplant recipients on everolimus-based immunosuppression.

Cardiac allograft vasculopathy (CAV) causes heart failure after heart transplantation (HTx), but its pathogenesis is incompletely understood. Notch signaling, possibly modulated by everolimus (EVR), is essential for processes involved in CAV. We hypothesized that circulating Notch ligands would be dysregulated after HTx. We studied circulating delta-like Notch ligand 1 (DLL1) and periostin (POSTN) and CAV in de novo HTx recipients (n = 70) randomized to standard or EVR-based, calcineurin inhibitor-free immunosuppression and in maintenance HTx recipients (n = 41). Compared to healthy controls, plasma DLL1 and POSTN were elevated in de novo (P < .01; P < .001) and maintenance HTx recipients (P < .001; P < .01). Use of EVR was associated with a treatment effect for DLL1. For de novo HTx recipients, a change in DLL1 correlated with a change in CAV at 1 (P = .021) and 3 years (P = .005). In vitro, activation of T cells increased DLL1 secretion, attenuated by EVR. In vitro data suggest that also endothelial cells and vascular smooth muscle cells (VSMCs) could contribute to circulating DLL1. Immunostaining of myocardial specimens showed colocalization of DLL1 with T cells, endothelial cells, and VSMCs. Our findings suggest a role of DLL1 in CAV progression, and that the beneficial effect of EVR on CAV could reflect a suppressive effect on DLL1. Trial registration numbers-SCHEDULE trial: ClinicalTrials.gov NCT01266148; NOCTET trial: ClinicalTrials.gov NCT00377962.

Effect of Everolimus Initiation and Calcineurin Inhibitor Elimination on Cardiac Allograft Vasculopathy in De Novo Heart Transplant Recipients.

Background Cardiac allograft vasculopathy (CAV) limits survival after heart transplantation, and the effect of different immunosuppressive regimens on CAV is not fully understood. The randomized SCHEDULE trial (Scandinavian Heart Transplant Everolimus De Novo Study With Early Calcineurin Inhibitors Avoidance) evaluated whether initiation of the proliferation signal inhibitor everolimus and early cyclosporine elimination can reduce CAV development. Methods and Results The SCHEDULE trial was a multicenter Scandinavian trial, where 115 de novo heart transplantation recipients were randomized to everolimus with complete cyclosporine withdrawal 7 to 11 weeks after heart transplantation or standard cyclosporine-based immunosuppression. Seventy-six (66%) patients had matched intravascular ultrasound examinations at baseline and 12 and 36 months. Intravascular ultrasound analysis evaluated maximal intimal thickness, percent atheroma volume, and total atheroma volume. Qualitative plaque analysis using virtual histology assessed fibrous, fibrofatty, and calcified tissue as well as necrotic core. Serum inflammatory markers were measured in parallel. The everolimus group (n=37) demonstrated significantly reduced CAV progression as compared with the cyclosporine group (n=39) at 36 months (Δ maximal intimal thickness, 0.09±0.05 versus 0.15±0.16 mm [ P=0.03]; Δ percent atheroma volume, 5.3±2.8% versus 7.6±5.9% [ P=0.03]; and Δ total atheroma volume, 33.9±71.2 versus 54.2±96.0 mm3 [ P=0.34], respectively]. At 36 months the number of everolimus patients with rejection graded ≥2R was 15 (41%) as compared with 5 (13%) in the cyclosporine group ( P=0.01). Everolimus did not affect CAV morphology or immune marker activity during the follow-up period. Conclusions The SCHEDULE trial demonstrates that everolimus initiation and early cyclosporine elimination significantly reduces CAV progression at 12 months, and this beneficial effect is clearly sustained at 36 months. Clinical trial registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT01266148.

Effect of everolimus vs calcineurin inhibitors on quality of life in heart transplant recipients during a 3-year follow-up: Results of a randomized controlled trial (SCHEDULE).

The Scandinavian heart transplant everolimus de novo study with early calcineurin inhibitors avoidance (SCHEDULE) trial was a 12 month, randomized, open-label, parallel-group trial that compared everolimus (EVR; n=56) to conventional CsA (n=59) immunosuppression. Previously, we reported that EVR outperformed CsA in improving renal function and coronary artery vasculopathy, despite a higher rejection rate with EVR. This study aimed to compare the effects of these treatments on quality of life (QoL). Within five post-operative days, patients (mean age 50±13 years, 27% women) were randomized to EVR or a standard CsA dosage (CsA group). This study assessed quality of life (QoL), based on the Short Form-36, EuroQol-5D, and Beck Depression Inventory (BDI). Assessments were performed pre-HTx and 12 and 36 months post-HTx. At 12 and 36 months, the groups showed similar improvements in Short Form-36 measures (at pre-HTx, 12 and 36 months the values were as follows: Physical component summary: EVR: 31.5±110.9, 49.1±9.7, and 47.9±10.6; P<.01; CsA: 32.5±8.2, 48.4±8.5, and 46.5±11.5; P<.01; mental component summary: EVR: 46.0±12.0, 51.7±11.9, and 52.1±13.0; P<.01; CsA: 38.2±12.5, 53.4±7.1, and 54.3±13.0; P<.01); similar decrease in mean BDI (EVR: 10.9±10.2, 5.4±4.7, and 8.1±9.0; P<.01; CsA: 11.8±7.1, 6.3±5.4, and 6.2±6.5; P<.01); and similar Euro Qol-improvements. Thus, in this small-sized study, EVR-based and conventional CsA immunosuppressive strategies produced similar QoL improvements.

Cognitive function after heart transplantation: Comparing everolimus-based and calcineurin inhibitor-based regimens.

BACKGROUND: Studies have shown conflicting results concerning the occurrence of cognitive impairment after successful heart transplantation (HTx). Another unresolved issue is the possible differential impact of immunosuppressants on cognitive function. In this study, we describe cognitive function in a cohort of HTx recipients and subsequently compare cognitive function between subjects on either everolimus- or calcineurin inhibitor (CNI)-based immunosuppression. METHODS: Cognitive function, covering attention, processing speed, executive functions, memory, and language functions, was assessed with a neuropsychological test battery. Thirty-seven subjects were included (everolimus group: n=20; CNI group: n=17). The extent of cerebrovascular pathology was assessed with magnetic resonance imaging. RESULTS: About 40% of subjects had cognitive impairment, defined as performance at least 1.5 standard deviations below normative mean in one or several cognitive domains. Cerebrovascular pathology was present in 33.3%. There were no statistically significant differences between treatment groups across cognitive domains. CONCLUSIONS: Given the high prevalence of cognitive impairment in the sample, plus the known negative impact of cognitive impairment on clinical outcome, our results indicate that cognitive assessment should be an integrated part of routine clinical follow-up after HTx. However, everolimus- and CNI-based immunosuppressive regimens did not show differential impacts on cognitive function.

Long-term effects of high-intensity interval training in heart transplant recipients: A 5-year follow-up study of a randomized controlled trial.

BACKGROUND: Previous studies have demonstrated that high-intensity interval training (HIT) is superior to moderate-continuous exercise in general and in cardiovascular diseases. Recently, we also found HIT safe and efficient after heart transplantation (HTx). This study reports the 5-year long-term effects. DESIGN AND METHODS: Forty-one HTx patients who had completed the previous 12-month randomized controlled trial, comparing HIT intervention with usual care, were eligible. In particular, we measured VO2peak , muscular capacity, intravascular ultrasound, and questionnaires measuring physical and mental health. RESULTS: The baseline mean±SD values were as follows: age; 49.1±16.5 years, men; 68%, time since HTx: 4.1±2.2 years. Within the HIT group, initial VO2peak increased significantly from 27.7±5.7 to 31.2±5.3 mL/kg/min. However, during the next 4 years, VO2peak decreased to 26.0±6.2 mL/kg/min. The control group showed slightly decreasing VO2peak values during the entire 5-year period. The HIT group reported significantly less anxiety symptoms, but there were no long-term differences in VO2peak , muscular capacity, or cardiac allograft vasculopathy between the groups. The similar VO2peak values correspond to our findings of similar everyday activity. CONCLUSION: Our findings suggest that intermittent periods of HIT may be necessary to maintain the initial benefits gained from the intervention. However, HIT probably reduces the burden of anxiety, which is a frequent health issue following HTx.

Effect of everolimus initiation and early calcineurin inhibitor withdrawal on myocardial FOXP3+ regulatory T cells in heart transplantation.

BACKGROUND: Through immunosuppression CD4+FoxP3+ regulatory T-cells (Tregs) play an indispensable role in allograft rejection. Post-HTx treatment with everolimus is associated with slower progression of cardiac allograft vasculopathy (CAV) - chronic rejection - than CNI based therapy. We hypothesized treatment with everolimus reduced the risk of CAV by modulating myocardial FoxP3 levels. METHODS: 15 patients from the Schedule trial comparing everolimus, MMF, steroid and early CNI (Everolimus, n=8) withdrawal to conventional CNI based immunosuppression (Controls, n=7) after de novo HTx were included and FoxP3+ cells were quantified in 56 endomyocardial biopsies, and compared in the two patient groups. CAV was evaluated invasively using coronary intravascular ultrasound (IVUS). RESULTS: Baseline FoxP3 biopsy levels were similar in the two groups. The Everolimus group showed a significant increase in Foxp3 densities from baseline to time of one-year follow-up (median (IQR)=4.8×10(-7)(20.4) Tregs/µm(2), P=0.046) while Controls showed no significant change (median (IQR)=3.1×10(-7)(6.5) Tregs/µm(2), P=0.116). At 1-month follow-up FoxP3 densities correlated with the observed change in TAV from baseline to time of 1-year follow-up (r=0.641, P=0.034). FoxP3 densities at 1-week predicted acute cellular rejection (ACR) levels at 1month (P=0.026). No other correlations with ACR were found. CONCLUSION: Everolimus treatment combined with early CNI elimination is associated with increased densities of Tregs 12-months post-HTx compared to patients receiving CNI based regimen. Furthermore, the density of myocardial FoxP3+ cells early after transplantation appears to predict at least one measure of CAV burden after one year.

Index of microvascular resistance after early conversion from calcineurin inhibitor to everolimus in heart transplantation: A sub-study to a 1-year randomized trial.

BACKGROUND: Microvascular function in transplanted hearts can be evaluated by methods used in routine left heart catheterization follow-up after heart transplantation (HTx). This sub-study of a randomized study compared the effects of everolimus (EVR) and calcineurin inhibitor (CNI) treatment on microvascular function as expressed by the index of microvascular resistance (IMR) at 1 year after HTx. A secondary objective was to compare the change in IMR from 7-11 weeks to 1 year after HTx between randomized groups. METHODS: There were 70 HTx recipients included and randomly assigned to combination therapy (EVR and CNI with early CNI withdrawal) vs conventional CNI treatment. Coronary physiologic assessment was performed 7-11 weeks and 1 year after HTx. A linear mixed model was used to assess the group difference at 1 year and the difference in IMR change between 7-11 weeks and 1 year after HTx. RESULTS: At 1 year, there was no significant difference in IMR between the EVR group (17.5 mm Hg∙sec ± 8.9) (mean ± SD) and the CNI group (14.9 mm Hg∙sec ± 6.6, p = 0.17). The difference in IMR change between the 2 treatment arms was 1.6 mm Hg∙sec (95% confidence interval, -2.8 to 5.9; p = 0.49). Spearman's rank correlation coefficient at 1 year after HTx between IMR and maximal intimal thickness as assessed with intravascular ultrasound in the left anterior descending artery was -0.13 (p = 0.28). CONCLUSIONS: In this prospective, open, randomized study comparing early CNI withdrawal with mammalian target of rapamycin inhibitors immunosuppression during the first year after HTx, early transition from CNI-based immunosuppression to EVR-based treatment did not result in differences in microvascular function as assessed by the IMR.

Design and rationale of the HITTS randomized controlled trial: Effect of High-intensity Interval Training in de novo Heart Transplant Recipients in Scandinavia.

There is no consensus on how, when, and at what intensity exercise should be performed and organized after heart transplantation (HTx). Most rehabilitation programs are conducted in HTx centers, which might be impractical and costly. We have recently shown that high-intensity interval training (HIT) is safe, well tolerated, and efficacious in maintenance HTx recipients, but there are no studies among de novo patients, and whether HIT is feasible and superior to moderate training in HTx recipients is unclear. A total of 120 clinically stable HTx recipients older than 18 years will be recruited from 3 Scandinavian HTx centers. Participants are randomized to HIT or moderate training, shortly after surgery. All exercises are supervised in the patients' local communities. Testing at baseline and follow-up includes the following: VO2peak (primary end point), muscle strength, body composition, quality of life, myocardial performance, endothelial function, biomarkers, and progression of cardiac allograft vasculopathy. A subgroup (n = 90) will also be tested at 3-year follow-up to assess long-term effects of exercise. So far, the HIT intervention is well tolerated, without any serious adverse events. We aim to test whether decentralized HIT is feasible, safe, and superior to moderate training, and whether it will lead to significant improvement in exercise capacity and less long-term complications.

The challenge of allograft vasculopathy in cardiac transplantation.

PURPOSE OF REVIEW: Cardiac allograft vasculopathy (CAV) is a unique form of accelerated atherosclerosis occurring in heart transplant recipients and this complication has a major negative impact on long-term survival. An understanding of recent advances in the understanding of CAV pathogenesis, accurate diagnosis and effective treatment is important given the increasing number of heart transplant procedures being performed annually. RECENT FINDINGS: This review article will discuss the complex immunological and nonimmunological processes that are likely to contribute to endothelial activation and the chronic inflammatory response causing intimal hyperplasia that is characteristic of CAV. Accurate diagnosis of CAV is essential, and both current and emerging imaging modalities will be reviewed. Finally, current treatment of CAV, together with future therapeutic strategies, will be discussed. SUMMARY: CAV is an important complication-limiting survival after heart transplant, and a clear understanding of the underlying pathophysiological processes is important. The diagnosis of CAV can be difficult, but it is possible with the appropriate imaging modalities. Effective treatment of CAV remains an important clinical challenge, and current immunosuppressive therapy has limited efficacy. However, newer immunosuppressive agents have demonstrated promising results in clinical trials, and this will hopefully allow more effective disease management in the near future.

Effect of high-intensity interval training on progression of cardiac allograft vasculopathy.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is a progressive form of atherosclerosis occurring in heart transplant (HTx) recipients, leading to increased morbidity and mortality. Given the atheroprotective effect of exercise on traditional atherosclerosis, we hypothesized that high-intensity interval training (HIIT) would reduce the progression of CAV among HTx recipients. METHODS: Forty-three cardiac allograft recipients (mean ± SD age 51 ± 16 years; 67% men; time post-HTx 4.0 ± 2.2 years), all clinically stable and >18 years old, were randomized to either a HIIT group or control group (standard care) for 1 year. The effect of training on CAV progression was assessed by intravascular ultrasound (IVUS). RESULTS: IVUS analysis revealed a significantly smaller mean increase [95% CI] in atheroma volume (PAV) of 0.9% [95% CI -;0.3% to 1.9%] in the HIIT group as compared with the control group, 2.5% [1.6% to 3.5%] (p = 0.021). Similarly, the mean increase in total atheroma volume (TAV) was 0.3 [0.0 to 0.6] mm(3)/mm in the HIT group vs 1.1 [0.6 to 1.7] mm(3)/mm in the control group (p = 0.020), and mean increase in maximal intimal thickness (MIT) was 0.02-0.01 to 0.04] mm in the HIIT group vs 0.05 [0.03 to 0.08] mm in the control group (p = 0.054). Qualitative plaque progression (virtual histology parameters) and inflammatory activity (biomarkers) were similar between the 2 groups during the study period. CONCLUSIONS: HIIT among maintenance HTx recipients resulted in a significantly impaired rate of CAV progression. Future larger studies should address whether exercise rehabilitation strategies should be included in CAV management protocols.

Early postoperative left ventricular function by echocardiographic strain is a predictor of 1-year mortality in heart transplant recipients.

BACKGROUND: Left ventricular (LV) function can be accurately assessed using two-dimensional speckle-tracking echocardiography. The association between reduced LV global longitudinal strain (LVGLS) magnitude and risk for mortality in heart transplant recipients is unclear. The aim of this study was to test the hypothesis that LVGLS could predict 1-year mortality in heart transplant recipients. METHODS: A total of 176 consecutive adult primary single-organ orthotopic heart transplant recipients were retrospectively evaluated. Of these, 167 had acceptable echocardiographic image quality and were included in the study. N-terminal pro-B-type natriuretic peptide, creatinine, C-reactive protein, and invasive hemodynamic parameters were measured, and echocardiography was performed 1 to 3 weeks after heart transplantation. LVGLS was averaged from regional strain in 16 LV segments. RESULTS: During the first year, 15 patients (9%) died 86 ± 72 days after heart transplantation. LVGLS and LV ejection fraction were decreased in magnitude in nonsurvivors (P < .05). They were older and had higher donor ages. Mean pulmonary capillary wedge pressures were similar in the two groups, while all other hemodynamic parameters were increased in nonsurvivors (P < .05). LVGLS was the only significant (P = .02) noninvasive independent predictor, with a hazard ratio of 1.42 (95% confidence interval, 1.07-1.88; P = .02) per 1% decrease in strain magnitude, while pulmonary vascular resistance was a significant (P < .001) invasive predictor, with a hazard ratio of 3.98 (95% confidence interval, 2.01-7.87) of 1-year mortality in multivariate Cox regression analysis. CONCLUSIONS: Reduced LV function and increased pulmonary vascular resistance are related to poor prognosis in heart transplant recipients. Early assessment of LVGLS might be a noninvasive predictor of 1-year mortality in these patients.

Peak oxygen uptake during cardiopulmonary exercise testing determines response to cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an established treatment modality for advanced heart failure (HF) but 20-30% of patients treated with CRT do not experience clinical improvement. Hence, in this study we aimed to investigate whether baseline cardiopulmonary exercise testing (CPX) can help improve the prediction of a positive functional CRT response. METHODS: This prospective observational study included 76 HF patients undergoing elective CRT implantation and clinical CPX and echocardiographic assessment were performed at baseline, 6, and 12 months. RESULTS: Peak VO2 increased from 11.0±2.5 ml/min/kg to 12.0±4.1 ml/min/kg and 12.2±3.5 ml/min/kg at 6 and 12 months after CRT, respectively. The number of patients classified as "CRT-responders" (Δ peak VO2≥1 ml/kg/min) was 33 (46%) and 36 (52%) at 6 and 12 months after CRT, respectively. Patients with baseline peak VO2<40% of predicted (lowest tertile) demonstrated a 68% and 69% response rate at 6 and 12 months, respectively, as compared to a 35% and 42% response rate among patients with baseline peak VO2≥40% of predicted (p=0.01 and p=0.02, respectively). In multivariate analysis patients with baseline peak VO2<40% of predicted had an adjusted odds ratio of 4.4 (95% CI 1.6-12.5; p<0.01) and 3.1 (95% CI 1.1-8.8; p=0.03) for positive CRT response at 6 and 12 months, respectively. CONCLUSIONS: Treatment with CRT improves exercise capacity but this increase is most substantial among patients with a lower baseline peak VO2 (% of predicted). Baseline CPX can, therefore, be utilized to identify patients more likely to exhibit a functional improvement after CRT.