Vasoreactivity and inhaled treprostinil response in interstitial lung disease pulmonary hypertension.

Introduction: Despite shared features with pulmonary arterial hypertension, acute vasoreactivity in pulmonary hypertension with interstitial lung disease (PH-ILD) is not well characterised, including its potential ability to predict therapeutic outcomes. We sought to determine whether acute vasoreactivity in PH-ILD to oxygen (O) and inhaled nitric oxide (iNO) predicts inhaled treprostinil (iTre) outcomes.

Materials And Methods: In this retrospective cohort analysis, we identified treatment-naive PH-ILD patients with vasoreactivity testing using O and O+iNO.

Prognostic relevance of exercise pulmonary hypertension: results of the multicentre PEX-NET Clinical Research Collaboration.

Background: Exercise pulmonary hypertension (PH) was defined by a mean pulmonary arterial pressure (mPAP)/cardiac output (CO) slope >3 mmHg·min·L between rest and exercise in the 2022 European Society of Cardiology/European Respiratory Society PH guidelines. However, large, multicentre studies on the prognostic relevance of exercise haemodynamics and its added value to resting haemodynamics are missing.

Patients And Methods: The PEX-NET (Pulmonary Haemodynamics during Exercise Network) registry enrolled patients who underwent clinically indicated right heart catheterisations both at rest and ergometer exercise from 23 PH centres worldwide.

Orthostatic intolerance with tachycardia (postural tachycardia syndrome) and without (hypocapnic cerebral hypoperfusion) represent a spectrum of the same disorder.

Background: Spectrum of chronic orthostatic intolerance without orthostatic hypotension includes postural tachycardia syndrome (POTS), with orthostatic tachycardia and hypocapnic cerebral hypoperfusion (HYCH), without orthostatic tachycardia. This study compared autonomic, cerebrovascular, and neuropathic features of POTS and HYCH.

Methods: This retrospective study evaluated patients with orthostatic intolerance referred for autonomic testing.

Mismatch between subjective and objective dysautonomia.

Autonomic symptom questionnaires are frequently used to assess dysautonomia. It is unknown whether subjective dysautonomia obtained from autonomic questionnaires correlates with objective dysautonomia measured by quantitative autonomic testing. The objective of our study was to determine correlations between subjective and objective measures of dysautonomia.

Deep learned representations of the resting 12-lead electrocardiogram to predict at peak exercise.

Aims: To leverage deep learning on the resting 12-lead electrocardiogram (ECG) to estimate peak oxygen consumption (V˙O2peak) without cardiopulmonary exercise testing (CPET).

Methods And Results: V ˙ O 2 peak estimation models were developed in 1891 individuals undergoing CPET at Massachusetts General Hospital (age 45 ± 19 years, 38% female) and validated in a separate test set (MGH Test, n = 448) and external sample (BWH Test, n = 1076). Three penalized linear models were compared: (i) age, sex, and body mass index ('Basic'), (ii) Basic plus standard ECG measurements ('Basic + ECG Parameters'), and (iii) basic plus 320 deep learning-derived ECG variables instead of ECG measurements ('Deep ECG-V˙O2').

Myalgic Encephalomyelitis-Chronic Fatigue Syndrome Common Data Element item content analysis.

Introduction: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a multisystem chronic disease estimated to affect 836,000-2.5 million individuals in the United States. Persons with ME/CFS have a substantial reduction in their ability to engage in pre-illness levels of activity.

Exercise Pathophysiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Postacute Sequelae of SARS-CoV-2: More in Common Than Not?

Topic Importance: Postacute sequelae of SARS-CoV-2 (PASC) is a long-term consequence of acute infection from COVID-19. Clinical overlap between PASC and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) has been observed, with shared symptoms including intractable fatigue, postexertional malaise, and orthostatic intolerance. The mechanistic underpinnings of such symptoms are poorly understood.

Perfusion imaging heterogeneity during NO inhalation distinguishes pulmonary arterial hypertension (PAH) from healthy subjects and has potential as an imaging biomarker.

Background: Without aggressive treatment, pulmonary arterial hypertension (PAH) has a 5-year mortality of approximately 40%. A patient's response to vasodilators at diagnosis impacts the therapeutic options and prognosis. We hypothesized that analyzing perfusion images acquired before and during vasodilation could identify characteristic differences between PAH and control subjects.

Network autonomic analysis of post-acute sequelae of COVID-19 and postural tachycardia syndrome.

Background: The autonomic nervous system (ANS) is a complex network where sympathetic and parasympathetic domains interact inside and outside of the network. Correlation-based network analysis (NA) is a novel approach enabling the quantification of these interactions. The aim of this study is to assess the applicability of NA to assess relationships between autonomic, sensory, respiratory, cerebrovascular, and inflammatory markers on post-acute sequela of COVID-19 (PASC) and postural tachycardia syndrome (POTS).

Orthostatic and Exercise Intolerance in Recreational and Competitive Athletes With Long COVID.

Post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (PASC) infection is particularly concerning to athletes who place a high premium on cardiovascular performance and competition. This initial case series shows the overlap between PASC and orthostatic intolerance in athletes, reveals the diagnostic challenges, and highlights the role of graded exercise training in this population. ().

Neurovascular Dysregulation and Acute Exercise Intolerance in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Randomized, Placebo-Controlled Trial of Pyridostigmine.

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is characterized by intractable fatigue, postexertional malaise, and orthostatic intolerance, but its pathophysiology is poorly understood. Pharmacologic cholinergic stimulation was used to test the hypothesis that neurovascular dysregulation underlies exercise intolerance in ME/CFS.

Research Question: Does neurovascular dysregulation contribute to exercise intolerance in ME/CFS, and can its treatment improve exercise capacity?

Study Design And Methods: Forty-five subjects with ME/CFS were enrolled in a single-center, randomized, double-blind, placebo-controlled trial.

Multisystem Involvement in Post-Acute Sequelae of Coronavirus Disease 19.

Objective: The purpose of this study was to describe cerebrovascular, neuropathic, and autonomic features of post-acute sequelae of coronavirus disease 2019 ((COVID-19) PASC).

Methods: This retrospective study evaluated consecutive patients with chronic fatigue, brain fog, and orthostatic intolerance consistent with PASC. Controls included patients with postural tachycardia syndrome (POTS) and healthy participants.

Noninvasive Scale Measurement of Stroke Volume and Cardiac Output Compared With the Direct Fick Method: A Feasibility Study.

Background Objective markers of cardiac function are limited in the outpatient setting and may be beneficial for monitoring patients with chronic cardiac conditions. We assess the accuracy of a scale, with the ability to capture ballistocardiography, electrocardiography, and impedance plethysmography signals from a patient's feet while standing on the scale, in measuring stroke volume and cardiac output compared with the gold-standard direct Fick method. Methods and Results Thirty-two patients with unexplained dyspnea undergoing level 3 invasive cardiopulmonary exercise test at a tertiary medical center were included in the final analysis.

Persistent Exertional Intolerance After COVID-19: Insights From Invasive Cardiopulmonary Exercise Testing.

Background: Some patients with COVID-19 who have recovered from the acute infection after experiencing only mild symptoms continue to exhibit persistent exertional limitation that often is unexplained by conventional investigative studies.

Research Question: What is the pathophysiologic mechanism of exercise intolerance that underlies the post-COVID-19 long-haul syndrome in patients without cardiopulmonary disease?

Study Design And Methods: This study examined the systemic and pulmonary hemodynamics, ventilation, and gas exchange in 10 patients who recovered from COVID-19 and were without cardiopulmonary disease during invasive cardiopulmonary exercise testing (iCPET) and compared the results with those from 10 age- and sex-matched control participants. These data then were used to define potential reasons for exertional limitation in the cohort of patients who had recovered from COVID-19.

Postural orthostatic tachycardia syndrome (POTS): Priorities for POTS care and research from a 2019 National Institutes of Health Expert Consensus Meeting - Part 2.

The National Institutes of Health hosted a workshop in 2019 to build consensus around the current state of understanding of the pathophysiology of postural orthostatic tachycardia syndrome (POTS) and to identify knowledge gaps that must be addressed to enhance clinical care of POTS patients through research. This second (of two) articles summarizes current knowledge gaps, and outlines the clinical and research priorities for POTS. POTS is a complex, multi-system, chronic disorder of the autonomic nervous system characterized by orthostatic intolerance and orthostatic tachycardia without hypotension.

Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting - Part 1.

Postural orthostatic tachycardia syndrome (POTS) is a chronic and often disabling disorder characterized by orthostatic intolerance with excessive heart rate increase without hypotension during upright posture. Patients often experience a constellation of other typical symptoms including fatigue, exercise intolerance and gastrointestinal distress. A typical patient with POTS is a female of child-bearing age, who often first displays symptoms in adolescence.

Insights From Invasive Cardiopulmonary Exercise Testing of Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) affects tens of millions worldwide; the causes of exertional intolerance are poorly understood. The ME/CFS label overlaps with postural orthostatic tachycardia (POTS) and fibromyalgia, and objective evidence of small fiber neuropathy (SFN) is reported in approximately 50% of POTS and fibromyalgia patients.

Research Question: Can invasive cardiopulmonary exercise testing (iCPET) and PGP9.

Impact of right ventricular work and pulmonary arterial compliance on peak exercise oxygen uptake in idiopathic pulmonary arterial hypertension.

Background: Pulmonary arterial hypertension (PAH) is associated with increased right ventricular (RV) afterload, RV dysfunction and decreased peak oxygen uptake (pVO). However, the pulmonary hemodynamic mechanisms measured by exercise right heart catheterization (RHC) that contribute to reduced pVO in idiopathic PAH (IPAH) are not completely characterized. Therefore, we sought to evaluate the exercise RHC determinants of pVO in patients with IPAH.

The Role of Exercise Testing in Pulmonary Vascular Disease: Diagnosis and Management.

Exercise intolerance is the dominant symptom of pulmonary hypertension (PH). The gold standard for the estimation of exercise capacity is a cycle ergometer incremental cardiopulmonary exercise test (CPET). The main clinical variables generated by a CPET are peak oxygen uptake (Vo2peak), ventilatory equivalents for carbon dioxide (VE/Vco), systolic blood pressure, oxygen (O2) pulse, and chronotropic responses.

Sex-Related Differences in Dynamic Right Ventricular-Pulmonary Vascular Coupling in Heart Failure With Preserved Ejection Fraction.

Background: Right ventricular (RV) dysfunction is associated with poorer outcomes in heart failure with preserved ejection fraction (HFpEF). Although female subjects are more likely to have HFpEF, male subjects have worse prognosis and resting RV function. The contribution of dynamic RV-pulmonary arterial (RV-PA) coupling between sex and its impact on peak exercise capacity (VO) in HFpEF is not known.

Dynamic right ventricular function response to incremental exercise in pulmonary hypertension.

Pulmonary hypertension is a progressive disease whose survival is linked to adequate right ventricle adaptation to its afterload. In the current study, we performed an in-depth characterization of right ventricle function during maximum incremental exercise in patients with pulmonary hypertension and how it relates to exercise capacity. A total of 377 pulmonary hypertension patients who completed a maximum symptom-limited invasive cardiopulmonary exercise testing were evaluated to identify 45 patients with heart failure with preserved ejection fraction, 48 with exercise pulmonary hypertension, and 47 with established pulmonary arterial hypertension.

Systemic vascular distensibility relates to exercise capacity in connective tissue disease.

Objective: Exercise intolerance is a common clinical manifestation of CTD. Frequently, CTD patients have associated cardio-pulmonary disease, including pulmonary hypertension or heart failure that impairs aerobic exercise capacity (pVO2). The contribution of the systemic micro-vasculature to reduced exercise capacity in CTD patients without cardiopulmonary disease has not been fully described.