A new day has come: Sotatercept for the treatment of pulmonary arterial hypertension.

Despite increasing therapeutic options and evolving treatment strategies, including targeting three therapeutic pathways, in the management of pulmonary arterial hypertension (PAH), morbidity and mortality have remained unacceptably high. Sotatercept is a first-in-class, novel activin signaling inhibitor approved for treating PAH based on evolving efficacy and safety evidence. This state-of-the-art review summarizes the current understanding of the mechanism of action, the impact on outcomes that improve how patients feel, function, and survive, and the safety and adverse event profile to inform readers of this breakthrough novel therapy.

Clinical trial design, end-points, and emerging therapies in pulmonary arterial hypertension.

Clinical trials in pulmonary arterial hypertension (PAH) have led to the approval of several effective treatments that improve symptoms, exercise capacity and clinical outcomes. In phase 3 clinical trials, primary end-points must reflect how a patient "feels, functions or survives". In a rare disease like PAH, with an ever-growing number of treatment options and numerous candidate therapies being studied, future clinical trials are now faced with challenges related to sample size requirements, efficiency and demonstration of incremental benefit on traditional end-points in patients receiving background therapy with multiple drugs. Novel clinical trial end-points, innovative trial designs and statistical approaches and new technologies may be potential solutions to tackle the challenges facing future PAH trials, but these must be acceptable to patients and regulatory bodies while preserving methodological rigour. In this World Symposium on Pulmonary Hypertension task force article, we address emerging trial end-points and designs, biomarkers and surrogate end-point validation, the concept of disease modification, challenges and opportunities to address diversity and representativeness, and the use of new technologies such as artificial intelligence in PAH clinical trials.

Prognosis Communication in Heart Failure: Experiences and Preferences of End-Stage Heart Failure Patients and Care Partners.

BACKGROUND: Patients with heart failure (HF) overestimate survival compared with model-predicted estimates, but the reasons for this discrepancy are poorly understood. We characterized how patients with end-stage HF and their care partners understand prognosis and elicited their preferences around prognosis communication. METHODS: We conducted in-depth, semistructured interviews with patients with end-stage HF and their care partners between 2021 and 2022 at a tertiary care center in Michigan. Participants were asked to describe barriers they faced to understanding prognosis. All interviews were coded and analyzed using an iterative content analysis approach. RESULTS: Fifteen patients with end-stage HF and 15 care partners participated, including 7 dyads. The median patient age was 66.5 years (range, 31-80) and included 9 of 15 (60%) White participants and 9 of 15 (60%) were males. Care partners included 10 of 15 (67%) White participants and 6 of 15 (40%) were males. Care partners were partners (n=7, 47%), siblings (n=4, 27%), parents (n=2, 13%), and children (n=2, 13%). Most patients demonstrated a poor understanding of their prognosis. In contrast, care partners commonly identified the patient's rapidly declining trajectory. Patients and care partners described ineffective prognosis communication with clinicians, common barriers to understanding prognosis, and similar suggestions on improving prognosis communication. Barriers to understanding prognosis included (1) conversation avoidance by physicians, (2) information inconsistency across different physicians, (3) distractions during prognosis communication due to emphasis on other conditions, and (4) confusion related to the use of medical jargon. Most patients and care partners wanted discussions around prognosis to begin early in the course of the disease, repeated routinely using layperson's terms, incorporating both quality of life and survival assessments, and involving care partners. Both patients and care partners did not expect precise survival estimates. CONCLUSIONS: Patients with end-stage HF demonstrate a poor understanding of their prognosis compared with their care partners. Patients and care partners are open to discussing prognosis early, using direct and patient-centered language.

Gastrointestinal bleeding following Heartmate 3 left ventricular assist device implantation: The Michigan Bleeding Risk Model.

BACKGROUND: Gastrointestinal bleeding (GIB) results in frequent hospitalizations and impairs quality of life in durable left ventricular assist device (LVAD) recipients. Anticipation of these events before implantation could have important implications for patient selection and management. METHODS: The study population included all adult HeartMate 3 (HM3) primary LVAD recipients enrolled in the STS Intermacs registry from January 2017 to December 2020. Using multivariable modeling methodologies, we investigated the relationships between preimplantation characteristics and postimplant bleeding, bleeding and death, and additional bleeding episodes on subsequent bleeding episodes and created a risk score to predict the likelihood of post-LVAD GIB based solely on preimplantation factors. RESULTS: Of 6,425 patients who received an HM3 LVAD, 1,010 (15.7%) patients experienced GIB. Thirteen preimplantation factors were independent predictors of post-LVAD GIB. A risk score was created from these factors and calculated for each patient. By 3 years postimplant, GIB occurred in 11%, 26%, and 43% of low-, medium- and high-risk patients, respectively. Experiencing 1 post-LVAD GIB event was associated with an increased risk for further GIB events, with 33.9% of patients experiencing at least 1 recurrence. While post-LVAD GIB was associated with mortality, there was no relationship between number of GIB events and death. CONCLUSIONS: The Michigan Bleeding Risk Model is a simple tool, which facilitates the prediction of post-LVAD GIB in HM3 recipients using 13 preimplant variables. The implementation of this tool may help in the risk stratification process and may have therapeutic and clinical implications in HM3 LVAD recipients.

Pulmonary Rehabilitation for Adults with Chronic Respiratory Disease: An Official American Thoracic Society Clinical Practice Guideline.

Background: Despite the known benefits of pulmonary rehabilitation (PR) for patients with chronic respiratory disease, this treatment is underused. Evidence-based guidelines should lead to greater knowledge of the proven benefits of PR, highlight the role of PR in evidence-based health care, and in turn foster referrals to and more effective delivery of PR for people with chronic respiratory disease. Methods: The multidisciplinary panel formulated six research questions addressing PR for specific patient groups (chronic obstructive pulmonary disease [COPD], interstitial lung disease, and pulmonary hypertension) and models for PR delivery (telerehabilitation, maintenance PR). Treatment effects were quantified using systematic reviews. The Grading of Recommendations, Assessment, Development and Evaluation approach was used to formulate clinical recommendations. Recommendations: The panel made the following judgments: strong recommendations for PR for adults with stable COPD (moderate-quality evidence) and after hospitalization for COPD exacerbation (moderate-quality evidence), strong recommendation for PR for adults with interstitial lung disease (moderate-quality evidence), conditional recommendation for PR for adults with pulmonary hypertension (low-quality evidence), strong recommendation for offering the choice of center-based PR or telerehabilitation for patients with chronic respiratory disease (moderate-quality evidence), and conditional recommendation for offering either supervised maintenance PR or usual care after initial PR for adults with COPD (low-quality evidence). Conclusions: These guidelines provide the basis for evidence-based delivery of PR for people with chronic respiratory disease.

Periprocedural Complications With Balloon Pulmonary Angioplasty: Analysis of Global Studies.

BACKGROUND: Balloon pulmonary angioplasty (BPA) was introduced as a treatment modality for patients with inoperable, medically refractory chronic thromboembolic pulmonary hypertension decades ago; however, reports of high rates of pulmonary vascular injury have led to considerable refinement in procedural technique. OBJECTIVES: The authors sought to better understand the evolution of BPA procedure-related complications over time. METHODS: The authors conducted a systematic review of original articles published by pulmonary hypertension centers globally and performed a pooled cohort analysis of procedure-related outcomes with BPA. RESULTS: This systematic review identified 26 published articles from 18 countries worldwide from 2013 to 2022. A total of 1,714 patients underwent 7,561 total BPA procedures with an average follow up of 7.3 months. From the first period (2013-2017) to the second period (2018-2022), the cumulative incidence of hemoptysis/vascular injury decreased from 14.1% (474/3,351) to 7.7% (233/3,029) (P < 0.01); lung injury/reperfusion edema decreased from 11.3% (377/3,351) to 1.4% (57/3,943) (P < 0.01); invasive mechanical ventilation decreased from 0.7% (23/3,195) to 0.1% (4/3,062) (P < 0.01); and mortality decreased from 2.0% (13/636) to 0.8% (8/1,071) (P < 0.01). CONCLUSIONS: Procedure-related complications with BPA, including hemoptysis/vascular injury, lung injury/reperfusion edema, mechanical ventilation, and death, were less common in the second period (2018-2022), compared with first period (2013-2017), likely from refinement in patient and lesion selection and procedural technique over time.

Greater geographic sharing and heart transplantation waitlist outcomes following the 2018 heart allocation policy.

BACKGROUND: In 2018, a new heart allocation policy was introduced to reduce variability in access to and outcomes after transplantation, in part, through attempts at broader geographic sharing of donor hearts. We evaluated how this policy affected geographic sharing and waitlist outcomes by donation service area (DSA). METHODS: This retrospective study of the Scientific Registry of Transplant Recipients database included adult patients waitlisted between October 2016 and October 2020, stratified by policy period. Our primary outcomes were mean proportion of imported and exported hearts aggregated by DSA as well as time to transplant. RESULTS: Following the policy change, there was substantial evidence of sharing across DSAs. The mean proportion of imported hearts transplanted by a DSA increased from 32% (95% CI: 27%-36%) to 74% (95% CI: 71%-78%; p < 0.001), and the mean proportion of exported hearts increased from 37% (95% CI: 33%-42%) to 75% (95% CI: 71%-79%; p < 0.001). The mean sharing ratio, defined as the log-transformed ratio of imported to exported hearts per DSA, shifted from 1.15 (95% CI: 0.88-1.42) to 1.02 (95% CI: 0.96-1.07), with a 76% decline in the variance across DSAs. As sharing increased, time to transplant per DSA declined from 153.9 days (95% CI, 143.4-164.4 days) pre-policy to 89.6 days (95% CI, 83.1-96.1 days) post-policy (p < 0.001). A larger decrease in waitlist time was associated with a higher proportion of exported hearts. CONCLUSIONS: The 2018 heart allocation policy was associated with more uniform access to heart transplantation and improved waitlist outcomes.

Racial Inequities in Access to Ventricular Assist Device and Transplant Persist After Consideration for Preferences for Care: A Report From the REVIVAL Study.

BACKGROUND: Racial disparities in access to advanced therapies for heart failure (HF) patients are well documented, although the reasons remain uncertain. We sought to determine the association of race on utilization of ventricular assist device (VAD) and transplant among patients with access to care at VAD centers and if patient preferences impact the effect. METHODS: We performed an observational cohort study of ambulatory chronic systolic HF patients with high-risk features and no contraindication to VAD enrolled at 21 VAD centers and followed for 2 years in the REVIVAL study (Registry Evaluation of Vital Information for VADs in Ambulatory Life). We used competing events cause-specific proportional hazard methodology with multiple imputation for missing data. The primary outcomes were (1) VAD/transplant and (2) death. The exposures of interest included race (Black or White), additional demographics, captured social determinants of health, clinician-assessed HF severity, patient-reported quality of life, preference for VAD, and desire for therapies. RESULTS: The study included 377 participants, of whom 100 (26.5%) identified as Black. VAD or transplant was performed in 11 (11%) Black and 62 (22%) White participants, although death occurred in 18 (18%) Black and 36 (13%) White participants. Black race was associated with reduced utilization of VAD and transplant (adjusted hazard ratio, 0.45 [95% CI, 0.23-0.85]) without an increase in death. Preferences for VAD or life-sustaining therapies were similar by race and did not explain racial disparities. CONCLUSIONS: Among patients receiving care by advanced HF cardiologists at VAD centers, there is less utilization of VAD and transplant for Black patients even after adjusting for HF severity, quality of life, and social determinants of health, despite similar care preferences. This residual inequity may be a consequence of structural racism and discrimination or provider bias impacting decision-making. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01369407.

Failure to rescue: A candidate quality metric for durable left ventricular assist device implantation.

OBJECTIVE: Failure to rescue (FTR), defined as death after a complication, is recognized as a principal driver of variation in mortality among hospitals. We evaluated FTR as a quality metric in patients who received durable left ventricular assist devices (LVADs) using the Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support. METHODS: Data on 13,617 patients who received primary durable LVADs from April 2012 to October 2017 at 131 hospitals that performed at least 20 implants were analyzed from the Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support. Rates of major complications and FTR were compared across risk-adjusted in-hospital mortality terciles (low, medium, high) and hospital volume. Logistic regression was used to estimate expected FTR rates on the basis of patient factors for each major complication. RESULTS: The overall unadjusted in-hospital mortality rate was 6.96%. Risk-adjusted in-hospital mortality rates varied 3.1-fold across terciles (low, 3.3%; high, 10.3%; P trend <.001). Rates of major complications varied 1.1-fold (low, 34.0%; high, 38.8%; P < .0001). Among patients with a major complication, 854 died in-hospital for an FTR rate of 17.7%, with 2.8-fold variation across mortality terciles (low, 8.5%; high, 23.9%; P < .0001). FTR rates were highest for renal dysfunction requiring dialysis (45.3%) and stroke (36.5%). Higher average annual LVAD volume was associated with higher rates of major complications (<10 per year, 26.7%; 10-20 per year, 34.0%; 20-30 per year, 34.0%; >30 per year, 40.1%; P trend <.0001) whereas hospitals implanting <10 per year had the highest FTR rate (<10 per year, 23.5%; 10-20 per year, 16.5%; 20-30 per year, 17.0%; >30 per year, 17.9%; P = .03). CONCLUSIONS: FTR might serve as an important quality metric for durable LVAD implant procedures, and identifying strategies for successful rescue after complications might reduce hospital variations in mortality.

Anatomical Variations in Pulmonary Arterial Branches in Patients Undergoing Evaluation for Chronic Thromboembolic Pulmonary Hypertension.

Background: Catheter-based interventions have emerged for both acute and chronic pulmonary thromboembolic disease. With this development and the need for segmental cannulation, anatomic understanding of pulmonary arterial segmental branch origination is important. We aim to describe the prevalence of different pulmonary arterial segmental branch origination patterns. Methods: This study included 179 consecutive patients who underwent bilateral nonselective invasive pulmonary angiography for the evaluation of chronic thromboembolic pulmonary hypertension. Results: In our study population (age, 59.0 ± 14.8 years, 55.3% female, 71% White), we found several anatomic variations of branches to the different lobes. These included 7 branching patterns in the right upper lobe, 3 in the right middle lobe, and 10 in the right lower lobe (4 patterns for the origin of the superior segmental artery and 6 for the origin of the basilar segmental arteries). On the left side, we found 8 patterns in the left upper lobe, with 5 involving lingular branches, and 9 in the left lower lobe (5 for the origin of the superior segmental artery and 4 for the basilar segmental pulmonary arteries). Although there were many variations, only 2-3 variations for each individual lobe accounted for >90% of the angiograms. Conclusions: Up to 3 anatomic branching patterns per lobe were noted to account for >90% of pulmonary artery branching variations in this study. This knowledge is not only useful for the interventionalist performing catheter-directed therapies but also for future research efforts that aim to standardize reporting of pulmonary angiographic findings.

Patient reported outcomes measures are infrequently used in clinical studies of heart transplant recipients.

BACKGROUND: Clinical trials in heart transplantation (HT) recipients have largely focused on objective outcomes such as survival; however, there is a paucity of data regarding the use of patient-reported outcome measures (PROMs) in these studies. We aimed to characterize the use of PROMs in registered clinical studies of HT recipients. METHODS: All clinical studies of adult HT recipients were queried from ClinicalTrials.gov and stratified by inclusion of PROMs. Studies reporting PROMs were identified via specific search terms using the "outcomes measures" field. Summary statistics compared characteristics of studies with and without PROMs. RESULTS: Between November 1999 and August 2022, 227 studies of HT recipients were registered on ClinicalTrials.gov. PROMs were included in 11% (n = 24/227) of studies. Studies reporting PROMs were more likely to be conducted outside of the United States (91.7% vs 54.2%, p < 0.001) and report a greater number of primary/secondary outcomes (PROMs: median 7 [interquartile ranges (IQR): 4, 9] vs no PROMs: median 3 [IQR: 2, 6]; p < 0.001). The majority of studies reporting PROMs (58.3%) were initiated after 2020. Twenty-one distinct PROM tools/domains were reported as outcome measures, with the Short Form Health Survey 36 being most frequently used (n = 10/24). Thirteen of the 21 PROMs included questions assessing mental health, whereas only 3 PROM tools were cardiac-specific. CONCLUSIONS: About 1 in 10 registered clinical trials of HT recipients includes PROMs, and mental health is the most commonly assessed PROM domain. Development and validation of PROM tools is needed to fully assess health-related quality of life in HT recipients.

Role of the mitral valve in left ventricular assist device pathophysiology.

Functional mitral regurgitation (MR) in the setting of heart failure results from progressive dilatation of the left ventricle (LV) and mitral annulus. This leads to leaflet tethering with posterior displacement. Contrary to common assumptions, MR often does not resolve with LVAD decompression of the LV alone. The negative impact of significant (moderate-severe) mitral regurgitation in the LVAD setting is becoming better recognized in terms of its harmful effect on right heart function, pulmonary vascular resistance and hospital readmissions. However, controversies remain regarding the threshold for intervention and management. At present, there are no consensus indications for the repair of significant mitral regurgitation at the time of LVAD implantation due to the conflicting data regarding potential adverse effects of MR on clinical outcomes. In this review, we summarize the current understanding of MR pathophysiology in patients supported with LVAD and potential future management strategies.