Cost-Effectiveness of Cardiovascular Magnetic Resonance for Rejection Surveillance After Cardiac Transplantation in the Australian Health Care System.

BACKGROUND: Heart transplantation is an effective treatment for end-stage congestive heart failure, however, achieving the right balance of immunosuppression to maintain graft function while minimising adverse effects is challenging. Serial endomyocardial biopsies (EMBs) are currently the standard for rejection surveillance, despite being invasive. Replacing EMB-based surveillance with cardiac magnetic resonance (CMR)-based surveillance for acute cardiac allograft rejection has shown feasibility. This study aimed to assess the cost-effectiveness of CMR-based surveillance in the first year after heart transplantation. METHOD: A prospective clinical trial was conducted with 40 orthotopic heart transplant (OHT) recipients. Participants were randomly allocated into two surveillance groups: EMB-based, and CMR-based. The trial included economic evaluations, comparing the frequency and cost of surveillance modalities in relation to quality-adjusted life years (QALYs) within the first year post-transplantation. Sensitivity analysis encompassed modelled data from observed EMB and CMR arms, integrating two hypothetical models of expedited CMR-based surveillance. RESULTS: In the CMR cohort, 238 CMR scans and 15 EMBs were conducted, versus (vs) 235 EMBs in the EMB group. CMR surveillance yielded comparable rejection rates (CMR 74 vs EMB 94 events, p=0.10) and did not increase hospitalisation risk (CMR 32 vs EMB 46 events, p=0.031). It significantly reduced the necessity for invasive EMBs by 94%, lowered costs by an average of AUD$32,878.61, and enhanced cumulative QALY by 0.588 compared with EMB. Sensitivity analysis showed that increased surveillance with expedited CMR Models 1 and 2 were more cost-effective than EMB (all p<0.01), with CMR Model 1 achieving the greatest cost savings (AUD$34,091.12±AUD$23,271.86 less) and utility increase (+0.62±1.49 QALYs, p=0.011), signifying an optimal cost-utility ratio. Model 2 showed comparable utility to the base CMR model (p=0.900) while offering the benefit of heightened surveillance frequency during periods of elevated rejection risk. CONCLUSIONS: CMR-based rejection surveillance in orthotopic heart transplant recipients provides a cost-effective alternative to EMB-based surveillance. Furthermore, it reduces the need for invasive procedures, without increased risk of rejection or hospitalisation for patients, and can be incorporated economically for expedited surveillance. These findings have important implications for improving patient care and optimising resource allocation in post-transplant management.

Ralinepag Phase II Open-Label Extension Study in Patients with Pulmonary Arterial Hypertension.

INTRODUCTION: Ralinepag is a potent, titratable, orally administered prostacyclin (IP) receptor agonist to treat pulmonary arterial hypertension. A phase II randomized, double-blind, parallel-group, placebo-controlled, 22-week study of immediate-release (IR) ralinepag safety and efficacy met its primary endpoint, significantly reducing pulmonary vascular resistance (PVR) compared with placebo. This phase II open-label extension (OLE) study assessed long-term safety and tolerability of ralinepag. METHODS: Participants were eligible for the OLE if they completed the parent study or experienced a clinical worsening event while receiving placebo. Those previously receiving IR ralinepag remained on their current dose, and participants formerly administered placebo were titrated to the highest tolerated dose. Participants were transitioned to an extended-release ralinepag formulation toward the end of the OLE. The primary objective evaluated long-term safety and tolerability; secondary endpoints included changes in 6-min walk distance (6MWD), World Health Organization/New York Heart Association functional class, clinical worsening, and hemodynamic measures. RESULTS: In total, 45/61 participants enrolled in the OLE study, 30 from the IR ralinepag group and 15 from the placebo group. The most common adverse events (AEs) were known prostacyclin-related effects (e.g., headache, 64.4%; diarrhea, 37.8%; jaw pain, 33.3%). There was a notable decline in AEs after reaching and maintaining a stable dose. At month 24 after entering the OLE, 6MWD significantly increased by a mean of 36.3 m (P = 0.004) from OLE baseline, and most participants remained stable in their functional class (84.8%). Post-baseline PVR in 1 or 2 years decreased by a median of 52.2 dyn.s/cm5 and mean pulmonary arterial pressure decreased by a median of 2.0 mmHg (P = 0.05). CONCLUSION: Ralinepag produced sustained, durable improvements in 6MWD along with durable reductions in PVR and a manageable AE profile. Most participants continuing treatment with ralinepag maintained functional measures throughout the OLE and those switching from placebo to ralinepag often experienced functional improvements.

Pulmonary arterial hypertension is a rare disease caused by elevated pressure in the blood vessels connecting the heart to the lungs. A previous phase 2 study found that ralinepag significanlty reduced pulmonary vascular resistance (the force or resistance that blood encounters as it flows through the blood vessels in the lungs) compared with placebo. This clinical study of 45 patients investigated whether ralinepag was safe and effective for long-term use to treat people with pulmonary arterial hypertension. All participants received ralinepag twice daily until a new once daily pill was available later in the study. The primary endpoints were long-term safety and tolerability, and secondary endpoints included exercise capacity, impact on daily life (functional class), clinical worsening, and hemodynamic measures (metrics to measure how well the heart is working). The study found that ralinepag had a manageable side effect profile, with a decrease in side effects for patients who continued taking ralinepag over time. Moreover, the study showed that ralinepag improved the ability to exercise, maintained functional measures, and helped to reduce pressure in the blood vessels connecting the heart to the lungs over a 24-month period for participants with pulmonary arterial hypertension.

Impact of Left Heart Disease Risk Factors on Outcomes in Pulmonary Arterial Hypertension Therapy.

BACKGROUND: Current guidelines recommend initial monotherapy for pulmonary arterial hypertension (PAH) with cardiopulmonary comorbidities, despite limited available evidence to guide management. RESEARCH QUESTION: Do left heart disease (LHD) risk factors have an impact on treatment response and influence applicability of risk assessment in a real-world cohort of patients with PAH? STUDY DESIGN AND METHODS: The Ambrisentan and Tadalafil in Patients with Pulmonary Arterial Hypertension (AMBITION) trial criteria was used to define the phenotype of patients with PAH with risk factors for LHD. Treatment strategy, functional outcome, long-term survival, and risk discrimination were compared with a reference PAH cohort using the Pulmonary Hypertension Society of Australia and New Zealand Registry. RESULTS: A total of 487 incident patients with PAH diagnosed between 2011 and 2020 were included. Of these, 103 (21.1%) fulfilled the definition of PAH with LHD risk factors, with 384 (78.9%) remaining as the reference group. Patients in the PAH with LHD risk factors group were older (66 ± 13 vs 58 ± 19 years; P < .001), had lower pulmonary vascular resistance (393 ± 266 vs 708 ± 391 dyn.s/cm5; P = .031), and had worse 6-min walk distance (286 ± 130 vs 327 ± 136 m; P = .005) at diagnosis. The PAH with LHD risk factors group was less likely to receive initial combination therapy (27% vs 44%; P = .02). Changes in 6-min walk distance at 12 months were similar in both groups (43 ± 77 m in the PAH with LHD risk factors group and 50 ± 90 m in the reference group; P = .50), including when stratified by initial treatment strategy (PAH with LHD risk factors group vs reference PAH group: monotherapy: 40 ± 81 vs 38 ± 95 m, P = .87; combination therapy: 53 ± 78 vs 64 ± 106 m, P = .511). Functional class improvements were also similar in both groups. REVEAL Registry 2.0 risk score effectively discriminated risk in both populations (C statistic = 0.756 for the PAH with LHD risk factors group and C statistic = 0.750 for the reference PAH group). There was no difference in survival between the two groups (log-rank test, P = .29). INTERPRETATION: In a real-world cohort, patients with PAH with LHD risk factors were less likely to be exposed to initial combination therapy. Nevertheless, selected patients with PAH with LHD risk factors who were treated with initial combination therapy derived similar functional response compared with the reference group. Further studies are needed to phenotype patients with PAH with cardiopulmonary comorbidities who may benefit from initial combination therapy.

DMD-Associated Dilated Cardiomyopathy: Genotypes, Phenotypes, and Phenocopies.

BACKGROUND: Variants in the DMD gene, that encodes the cytoskeletal protein, dystrophin, cause a severe form of dilated cardiomyopathy (DCM) associated with high rates of heart failure, heart transplantation, and ventricular arrhythmias. Improved early detection of individuals at risk is needed. METHODS: Genetic testing of 40 male probands with a potential X-linked genetic cause of primary DCM was undertaken using multi-gene panel sequencing, multiplex polymerase chain reaction, and array comparative genomic hybridization. Variant location was assessed with respect to dystrophin isoform patterns and exon usage. Telomere length was evaluated as a marker of myocardial dysfunction in left ventricular tissue and blood. RESULTS: Four pathogenic/likely pathogenic DMD variants were found in 5 probands (5/40: 12.5%). Only one rare variant was identified by gene panel testing with 3 additional multi-exon deletion/duplications found following targeted assays for structural variants. All of the pathogenic/likely pathogenic DMD variants involved dystrophin exons that had percent spliced-in scores >90, indicating high levels of constitutive expression in the human adult heart. Fifteen DMD variant-negative probands (15/40: 37.5%) had variants in autosomal genes including TTN, BAG3, LMNA, and RBM20. Myocardial telomere length was reduced in patients with DCM irrespective of genotype. No differences in blood telomere length were observed between genotype-positive family members with/without DCM and controls. CONCLUSIONS: Primary genetic testing using multi-gene panels has a low yield and specific assays for structural variants are required if DMD-associated cardiomyopathy is suspected. Distinguishing X-linked causes of DCM from autosomal genes that show sex differences in clinical presentation is crucial for informed family management.

Pre-operative pulmonary artery pulsatility index does not predict mortality post-cardiac transplantation.

AIMS: The pulmonary artery pulsatility index (PAPi) is a novel haemodynamic marker that has previously been shown to predict right ventricular dysfunction and mortality in patients with pulmonary hypertension and advanced heart failure. Utility of the PAPi in predicting outcomes post-cardiac transplantation is unknown. The aim of this study was to compare the prognostic significance of PAPi against pulmonary vascular resistance (PVR) for the predication of morbidity and all-cause mortality post-transplantation. METHODS AND RESULTS: All patients who underwent cardiac transplantation over a 6 year period were studied. Pre-operative right heart catheter data was obtained. The PAPi was calculated as follows: (systolic pulmonary artery pressure [sPAP] - diastolic pulmonary artery pressure [dPAP])/right atrial (RA) pressure. One hundred fifty-eight patients with a mean age of 49 ± 14 years were studied (43 with a pre-transplant left ventricular assist device [LVAD]). Three patients were excluded due to missing data. In the non-LVAD group, there was no significant difference in PAPi or PVR, nor was there any association with post-operative outcome (including stratification by natural history sub-type; all P > 0.05). In the LVAD group, there was no association with PAPi and post-operative outcome; however, PVR was predictive of post-operative mortality (mortality: 2.8 ± 1.3 WU vs. alive: 1.7 ± 0.7 WU; P = 0.005). CONCLUSIONS: The PAPi was not able to discriminate mortality outcomes for patients post-cardiac transplantation. Pulmonary vascular resistance remains a marker of mortality in an LVAD cohort bridged to transplant (central illustration).

Tricuspid Regurgitation After Heart Transplantation: The Cause or the Result of Graft Dysfunction?

BACKGROUND: Tricuspid regurgitation (TR) is common following heart transplantation and has been shown to adversely influence patient outcomes. The aim of this study was to identify causes of progression to moderate-severe TR in the first 2 y after transplantation. METHODS: This was a retrospective, single-center study of all patients who underwent heart transplantation over a 6-y period. Transthoracic echocardiogram (TTE) was performed at month 0, between 6 and 12 mo, and 1-2 y postoperatively to determine the presence and severity of TR. RESULTS: A total of 163 patients were included, of whom 142 underwent TTE before first endomyocardial biopsy. At month 0, 127 (78%) patients had nil-mild TR before first biopsy, whereas 36 (22%) had moderate-severe TR. In patients with nil-mild TR, 9 (7%) progressed to moderate-severe TR by 6 mo and 1 underwent tricuspid valve (TV) surgery. Of patients with moderate-severe TR before first biopsy, by 2 y, 3 had undergone TV surgery. The use of postoperative extracorporeal membrane oxygenation (ECMO) in the latter group was significant (78%; P < 0.05) as was rejection profile ( P = 0.02). Patients with late progressive moderate-severe TR had a significantly higher 2-y mortality than those who had moderate-severe TR immediately. CONCLUSIONS: Overall, our study has shown that in the 2 main groups of interest (early moderate-severe TR and progression from nil-mild to moderate-severe TR), TR is more likely to be the result of significant underling graft dysfunction rather than the cause of it.

Rapid triage and transition to telehealth for heart transplant patients in the COVID-19 pandemic setting.

BACKGROUND: In the setting of the COVID-19 pandemic, a rapid uptake of telehealth services was instituted with the aim of reducing the spread of disease to vulnerable patient populations including heart transplant recipients. METHODS: Single-center, cohort study of all heart transplant patients seen by our institution's transplant program during the first 6 weeks of transition from in-person consultation to telehealth (23 March - 5 June 2020). RESULTS: Face-to-face consultation allocation strongly favored patients in the early post-operative period (34 vs. 242 weeks post-transplant; p < 0.001). Telehealth consultation dramatically reduced patient travel and wait times (80 min per visit saved in telehealth patients). No apparent excess re-hospitalization or mortality was seen in telehealth patients. CONCLUSIONS: With appropriate triage, telehealth was feasible in heart transplant recipients, with videoconferencing being the preferred modality. Patients seen face-to-face were those triaged to be higher acuity based on time since transplant and overall clinical status. These patients have the expected higher rates of hospital re-admission, and therefore should continue to be seen in person.

Acute Vasoreactivity Testing and Outcomes in Pulmonary Arterial Hypertension: A Call for Increased Testing.

BACKGROUND: Pulmonary arterial hypertension (PAH) has a progressive, unremitting clinical course. Vasoreactivity testing (VdT) during right heart catheterisation (RHC) identifies a subgroup with excellent long-term response to calcium channel blockade (CCB). Reporting on these patients is limited. Established in 2011, the Pulmonary Hypertension Society of Australia and New Zealand (PHSANZ) registry offers the opportunity to assess the frequency of VdT during RHC, treatment and follow up of PAH patients. METHODS: Registry data from 3,972 PAH patients with index RHC revealed 1,194 VdT appropriate patients. Data was analysed in three groups: 1) VdT+CCB+: VdT positive, CCB treated; 2) VdT+CCB-: VdT positive, no CCB prescribed, 3) VdT-/noVdT: VdT negative, or VdT not tested. Data was reviewed for adherence to guidelines, clinical response (World Health Organization functional class [WHO FC], 6-minute-walk-distance [6MWD], RHC), and outcomes (survival or lung transplantation). RESULTS: Patients included had idiopathic (IPAH=1,087), heritable (HPAH=67) and drug or toxin-induced PAH (DPAH=40). A VdT was performed in 22% (268/1,194), with incomplete data in 26% (70/268); 28% (55/198) were VdT+. Analysis group allocation was: VdT+CCB+ (33/55), VdT+CCB- (22/55), VdT- (143)/noVdT (996). From patients with 1-year data VdT+CCB+ and VdT-/noVdT patients improved WHO FC, 6MWD and cardiac index (CI); VdT+CCB- data remained similar. Within the VdT+CCB+ group, 30% (10/33) were long-term CCB responders with a 100% 5-year survival; non-responders had a 61% survival at 5.4 years. Long-term responders were younger at diagnosis (40 yrs vs 54 yrs). CONCLUSION: Use of VdT testing and documentation is poor in this contemporary patient cohort. Nonetheless, survival in VdT+CCB+ patients from the PHSANZ registry is excellent, supporting guidelines promoting VdT testing. Strategies to promote the use of VdT are warranted.

Heart Transplantation From DCD Donors in Australia: Lessons Learned From the First 74 Cases.

Heart transplantation from donation after circulatory death (DCD) donors has the potential to substantially increase overall heart transplant activity. The aim of this report is to review the first 8 y of our clinical heart transplant program at St Vincent's Hospital Sydney, to describe how our program has evolved and to report the impact that changes to our retrieval protocols have had on posttransplant outcomes. Since 2014, we have performed 74 DCD heart transplants from DCD donors utilizing a direct procurement protocol followed by normothermic machine perfusion. Changes to our retrieval protocol have resulted in a higher retrieval rate from DCD donors and fewer rejections of DCD hearts during normothermic machine perfusion. Compared with our previously reported early experience in the first 23 transplants, we have observed a significant reduction in the incidence of severe primary graft dysfunction from 35% (8/23) to 8% (4/51) in the subsequent 51 transplant recipients ( P < 0.01). The only withdrawal time interval significantly associated with severe primary graft dysfunction was the asystolic warm ischemic time: 15 (12-17) versus 13 (11-14) min ( P < 0.05). One- and 5-y survival of DCD heart transplant recipients was 94% and 88%, comparable to that of a contemporary cohort of donation after brain death recipients: 87 and 81% ( P -value was not significant). In conclusion, heart transplantation from DCD donors has become a major contributor to our overall transplant activity accounting for almost 30% of all transplants performed by our program in the last 2 y, with similar DCD and donation after brain death outcomes.

Efficacy of bortezomib, cyclophosphamide and dexamethasone in cardiac AL amyloidosis.

Cardiac light chain (AL) amyloidosis is a condition with a very poor prognosis. We report a retrospective analysis comparing the traditional melphalan and dexamethasone protocol with cyclophosphamide, bortezomib and dexamethasone in late-stage cardiac AL amyloidosis. The primary end points were overall survival and haematological response. Both regimens provided meaningful responses in this difficult to treat patient group.

Cardiovascular Magnetic Resonance for Rejection Surveillance After Cardiac Transplantation.

BACKGROUND: Endomyocardial biopsy (EMB) is the gold standard method for surveillance of acute cardiac allograft rejection (ACAR) despite its invasive nature. Cardiovascular magnetic resonance (CMR)-based myocardial tissue characterization allows detection of myocarditis. The feasibility of CMR-based surveillance for ACAR-induced myocarditis in the first year after heart transplantation is currently undescribed. METHODS: CMR-based multiparametric mapping was initially assessed in a prospective cross-sectional fashion to establish agreement between CMR- and EMB-based ACAR and to determine CMR cutoff values between rejection grades. A prospective randomized noninferiority pilot study was then undertaken in adult orthotopic heart transplant recipients who were randomized at 4 weeks after orthotopic heart transplantation to either CMR- or EMB-based rejection surveillance. Clinical end points were assessed at 52 weeks. RESULTS: Four hundred one CMR studies and 354 EMB procedures were performed in 106 participants. Forty heart transplant recipients were randomized. CMR-based multiparametric assessment was highly reproducible and reliable at detecting ACAR (area under the curve, 0.92; sensitivity, 93%; specificity, 92%; negative predictive value, 99%) with greater specificity and negative predictive value than either T1 or T2 parametric CMR mapping alone. High-grade rejection occurred in similar numbers of patients in each randomized group (CMR, n=7; EMB, n=8; P=0.74). Despite similarities in immunosuppression requirements, kidney function, and mortality between groups, the rates of hospitalization (9 of 20 [45%] versus 18 of 20 [90%]; odds ratio, 0.091; P=0.006) and infection (7 of 20 [35%] versus 14 of 20 [70%]; odds ratio, 0.192; P=0,019) were lower in the CMR group. On 15 occasions (6%), patients who were randomized to the CMR arm underwent EMB for clarification or logistic reasons, representing a 94% reduction in the requirement for EMB-based surveillance. CONCLUSIONS: A noninvasive CMR-based surveillance strategy for ACAR in the first year after orthotopic heart transplantation is feasible compared with EMB-based surveillance. REGISTRATION: HREC/13/SVH/66 and HREC/17/SVH/80. AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY: ACTRN12618000672257.

Impact of frailty on mortality and morbidity in bridge to transplant recipients of contemporary durable mechanical circulatory support.

BACKGROUND: Frailty is associated with adverse outcomes in advanced heart failure. We studied the impact of frailty on postoperative outcomes in bridge to transplant (BTT) durable mechanical circulatory support (MCS) recipients. METHODS: Patients undergoing left ventricular assist device (LVAD, n = 96) or biventricular support (BiV, n = 11) as BTT underwent frailty assessment. Frailty was defined as ≥ 3 physical domains of the Fried's Frailty Phenotype (FFP) or ≥ 2 physical domains of the FFP plus cognitive impairment on the Montreal Cognitive Assessment (MoCA). RESULTS: No difference in mortality at 360 days was observed in frail (n = 6/38, 15.8%) vs non-frail (n = 4/58, 6.9%) LVAD supported patients, p = 0.19. However, there was a significant excess mortality in frail BiV (n = 4/5) vs non-frail BiV (n = 0/6) supported patients, p = 0.013. In all patients, frail patients compared to non-frail patients experienced longer intensive care unit stay, 12 vs 6 days (p < 0.0001) and hospital length of stay, 48 vs 27 days (p < 0.0001). There was no difference in hemocompatibility and infection related adverse events. The majority (n = 22/29, 75.9%) of frail patients became non-frail following MCS; contrastingly, a minority (n = 3/42, 7.1%) became frail from being non-frail (p = 0.0003). CONCLUSIONS: Abnormal markers of frailty are common in patients undergoing BTT-MCS support and those used herein predict mortality in BiV-supported patients, but not in LVAD patients. These findings may help us better identify patients who will benefit most from BiV-BTT therapy.

Interplay of sex hormones and long-term right ventricular adaptation in a Dutch PAH-cohort.

BACKGROUND: To investigate the association between altered sex hormone expression and long-term right ventricular (RV) adaptation and progression of right heart failure in a Dutch cohort of Pulmonary Arterial Hypertension (PAH)-patients across a wide range of ages. METHODS: In this study we included 279 PAH-patients, of which 169 females and 110 males. From 59 patients and 21 controls we collected plasma samples for sex hormone analysis. Right heart catheterization (RHC) and/or cardiac magnetic resonance (CMR) imaging was performed at baseline. For longitudinal data analysis, we selected patients that underwent a RHC and/or CMR maximally 1.5 years prior to an event (death or transplantation, N = 49). RESULTS: Dehydroepiandrosterone-sulfate (DHEA-S) levels were reduced in male and female PAH-patients compared to controls, whereas androstenedione and testosterone were only reduced in female patients. Interestingly, low DHEA-S and high testosterone levels were correlated to worse RV function in male patients only. Subsequently, we analyzed prognosis and RV adaptation in females stratified by age. Females ≤45years had best prognosis in comparison to females ≥55years and males. No differences in RV function at baseline were observed, despite higher pressure-overload in females ≤45years. Longitudinal data demonstrated a clear distinction in RV adaptation. Although females ≤45years had an event at a later time point, RV function was more impaired at end-stage disease. CONCLUSIONS: Sex hormones are differently associated with RV function in male and female PAH-patients. DHEA-S appeared to be lower in male and female PAH-patients. Females ≤45years could persevere pressure-overload for a longer time, but had a more severe RV phenotype at end-stage disease.

Validation of Cognitive Impairment in Combination With Physical Frailty as a Predictor of Mortality in Patients With Advanced Heart Failure Referred for Heart Transplantation.

BACKGROUND: The aim of this study was to validate our previous finding that frailty predicts early mortality in patients with advanced heart failure (AHF) and that including cognition in the frailty assessment enhances the prediction of mortality. METHODS: Patients with AHF referred to our Transplant Unit between November 2015 and April 2020 underwent physical frailty assessment using the modified Fried physical frailty (PF) phenotype as well as cognitive assessment using the Montreal Cognitive Assessment to identify patients who were cognitively frail (CogF). We assessed the predictive value of the 2 frailty measures (PF ≥ 3 of 5 = frail; CogF ≥ 3 of 6 = frail) for pretransplant mortality. RESULTS: Three hundred thirteen patients (233 male and 80 female; age 53 ± 13 y) were assessed. Of these, 224 patients (72%) were nonfrail and 89 (28%) were frail using the PF. The CogF assessment identified an additional 30 patients as frail: 119 (38%). Frail patients had significantly increased mortality as compared to nonfrail patients. Ventricular assist device and heart transplant-censored survival at 12 mo was 92 ± 2 % for nonfrail and 69 ± 5% for frail patients (P < 0.0001) using the CogF instrument. CONCLUSIONS: This study validates our previously published findings that frailty is prevalent in patients with AHF referred for heart transplantation. PF predicts early mortality. The addition of cognitive assessment to the physical assessment of frailty identifies an additional cohort of patients with a similarly poor prognosis.

Chronic thromboembolic pulmonary hypertension in Australia and New Zealand: An analysis of the PHSANZ registry.

BACKGROUND AND OBJECTIVE: Chronic thromboembolic pulmonary hypertension (CTEPH) is a serious condition occurring in 2%-4% of patients after acute pulmonary embolism. Pulmonary endarterectomy (PEA) is a potential cure for technically operable disease. The epidemiology and long-term outcomes of CTEPH have not been previously described in Australia and New Zealand. METHODS: Data were extracted from the Pulmonary Hypertension Society of Australia and New Zealand (PHSANZ) registry for patients diagnosed with CTEPH between January 2004 and March 2020. Baseline characteristics, treatment strategies, outcome data and long-term survival are reported. RESULTS: A total of 386 patients were included with 146 (37.8%) undergoing PEA and 240 (62.2%) in the non-PEA group. PEA patients were younger (55 ± 16 vs. 62 ± 16 years, p < 0.001) with higher baseline 6-min walk distance (6MWD; 405 ± 122 vs. 323 ± 146 m, p = 0.021), whilst both groups had similar baseline pulmonary haemodynamics. Pulmonary hypertension-specific therapy was used in 54% of patients post-PEA and 88% in the non-PEA group. The 1-, 3- and 5-year survival rates were 93%, 87% and 84% for the PEA group compared to 86%, 73% and 62%, respectively, for the non-PEA group (p < 0.001). Multivariate survival analysis showed baseline 6MWD was an independent predictor of survival in both operated and medically managed patients. CONCLUSION: In this first multicentre report of CTEPH in Australia and New Zealand, long-term survival is comparable to that in other contemporary CTEPH registries. However, PEA was only performed in a minority of CTEPH patients (37.8%) and significantly less than overseas reports. Greater awareness of PEA and improved patient access to experienced CTEPH centres are important priorities.

Waitlist and post-transplant outcomes for eisenmenger syndrome: A comparison of transplant strategies.

BACKGROUND: End-stage Eisenmenger syndrome (ES) due to unrepaired atrial septal defect (ASD) or ventricular septal defect (VSD) is an indication for lung transplantation (LTx) or heart-lung transplantation (HLTx). Limited evidence exists as to the optimal transplant strategy for this unique population. AIM: To describe waitlist characteristics and post-transplant outcomes in patients with ES-ASD or ES-VSD. METHODS: Using the ISHLT Registry, data were extracted for all ES-ASD or ES-VSD patients who underwent transplantation between 1987 and 2018. Additional data were sought for patients listed for LTx or HLTx in the OPTN Registry during the same period. Early era was defined as 1987-2004, and current era was defined as 2005-2018. RESULTS: In the current era, patients with ES-ASD or ES-VSD represented a lessening proportion of all LTx and HLTx. Compared to LTx for other indications, the odds of transplantation were significantly less for both ES-ASD 0.18 [0.07-0.50] and ES-VSD 0.03 [0.004-0.22]. In the early era, an equivalent survival was observed for ES-ASD who underwent HLTx versus LTx (p = 0.47), and superior survival for ES-VSD (p = 0.015). In contrast, ES-ASD patients who underwent LTx from the current era displayed better survival compared with HLTx, 10-year survival 52% vs 30% p = 0.036. Similar survival were observed for ES-VSD for both transplant strategies (p = 0.68). CONCLUSION: LTx shows superior survival outcomes in the current era for ES ASD patients, and equivalent outcomes for ES-VSD. In the current era, ES-ASD or ES-VSD patients were less likely to be transplanted than other candidates for LTx.

Everolimus for the Prevention of Calcineurin-Inhibitor-Induced Left Ventricular Hypertrophy After Heart Transplantation (RADTAC Study).

OBJECTIVES: This study aimed to determine the safety and efficacy of combined low-dose everolimus and low-dose tacrolimus compared with standard-dose tacrolimus in attenuating left ventricular hypertrophy (LVH) after orthotopic heart transplantation (OHT). BACKGROUND: Calcineurin inhibitors (CNIs) such as tactrolimus are important in preventing cardiac allograft rejection and reducing mortality after OHT. However CNIs are causatively linked to the development of LVH, and are associated with nephrotoxicity and vasculopathy. CNI-sparing agents such as everolimus have been hypothesized to inhibit adverse effects of CNIs. METHODS: In this prospective, randomized, open-label study, OHT recipients were randomized at 12 weeks after OHT to a combination of low-dose everolimus and tacrolimus (the RADTAC group) or standard-dose tacrolimus (the TAC group), with both groups coadministered mycophenolate and prednisolone. The primary endpoint was LVH indexed as the change in left ventricular mass (ΔLVM) by cardiovascular magnetic resonance (CMR) imaging from 12 to 52 weeks. Secondary endpoints included CMR-based myocardial performance, T1 fibrosis mapping, blood pressure, and renal function. Safety endpoints included episodes of allograft rejection and infection. RESULTS: Forty stable OHT recipients were randomized. Recipients in the RADTAC group had significantly lower tacrolimus levels compared with the TAC group (6.5 ± 3.5 µg/l vs. 8.6 ± 2.8 µg/l; p = 0.02). The mean everolimus level in the RADTAC group was 4.2 ± 1.7 µg/l. A significant reduction in LVM was observed in the RADTAC group compared with an increase in LVM in the TAC group (ΔLVM = -13.0 ± 16.8 g vs. 2.1 ± 8.4 g; p < 0.001). Significant differences were also noted in secondary endpoints measuring function and fibrosis (Δ circumferential strain = -2.9 ± 2.8 vs. 2.1 ± 2.3; p < 0.001; ΔT1 mapping values = -32.7 ± 51.3 ms vs. 26.3 ± 90.4 ms; p = 0.003). No significant differences were observed in blood pressure (Δ mean arterial pressure = 4.2 ± 18.8 mm Hg vs. 2.8 ± 13.8 mm Hg; p = 0.77), renal function (Δ creatinine = 3.1 ± 19.9 µmol/l vs. 9 ± 21.8 µmol/l; p = 0.31), frequency of rejection episodes (p = 0.69), or frequency of infections (p = 0.67) between groups. CONCLUSIONS: The combination of low-dose everolimus and tacrolimus compared with standard-dose tacrolimus safely attenuates LVH in the first year after cardiac transplantation with an observed reduction in CMR-measured fibrosis and an improvement in myocardial strain.

Impact of lung morphology on clinical outcomes with riociguat in patients with pulmonary hypertension and idiopathic interstitial pneumonia: A post hoc subgroup analysis of the RISE-IIP study.

BACKGROUND: Riociguat in Patients with Symptomatic Pulmonary Hypertension associated with Idiopathic Interstitial Pneumonias (RISE-IIP), a randomized, controlled, phase 2b trial of riociguat for pulmonary hypertension associated with idiopathic interstitial pneumonia, was terminated early due to increased mortality in riociguat-treated patients. Baseline characteristics of enrolled patients demonstrated a low diffusing capacity of the lung for carbon monoxide (DLCO) with preserved lung volumes at baseline, suggesting the presence of combined pulmonary fibrosis and emphysema (CPFE) in some patients. This post hoc analysis of RISE-IIP was undertaken to explore lung morphology, assessed by high-resolution computed tomography, and associated clinical outcomes. METHODS: Available baseline/pre-baseline high-resolution computed tomography scans were reviewed centrally by 2 radiologists. The extent of emphysema and fibrosis was retrospectively scored and combined to provide the total CPFE score. RESULTS: Data were available for 65/147 patients (44%), including 15/27 fatal cases (56%). Of these, 41/65 patients (63%) had CPFE. Mortality was higher in patients with CPFE (12/41; 29%) than those without (3/24; 13%). Fourteen patients with CPFE had emphysema > fibrosis (4 died). No relationship was observed between CPFE score, survival status, and treatment assignment. A low DLCO, short 6-min walking distance, and high forced vital capacity:DLCO ratio at baseline also appeared to be risk factors for mortality. CONCLUSIONS: High parenchymal lung disease burden and the presence of more emphysema than fibrosis might have predisposed patients with pulmonary hypertension associated with idiopathic interstitial pneumonia to poor outcomes in RISE-IIP. Future studies of therapy for group 3 pulmonary hypertension should include centrally adjudicated imaging for morphologic phenotyping and disease burden evaluation during screening.