Silvia Ulrich

• University of Zurich

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide and contributes significantly to reduced quality of life due to symptoms such as dyspnea and exercise intolerance. Eccentric cycling exercise (ECC) has shown potential as an alternative to conventional concentric cycling exercise (CON) i...

In an unselected obstructive sleep apnoea (OSA) population, continuous positive airway pressure (CPAP) slightly lowers blood pressure (BP). The aim was to investigate the differential effects of CPAP on BP in different OSA severities. Medline was searched through December 2023 for randomised controlled trials (RCTs) on the effect of CPAP compared t...

This study aimed to quantify the effect of two consecutive prolonged, intermittent exposures to high and very high altitudes on oxygen saturation (SpO2) and acute mountain sickness (AMS). For this, healthy lowlanders (N = 21), aged 18–30 years, underwent two 7-day sojourns at the ALMA observatory, Chile (6 h/day at 5050 m, 18 h/day at 2900 m), sepa...

Introduction In pulmonary arterial hypertension (PAH) and distal chronic thromboembolic pulmonary hypertension (CTEPH), the consistent use of disease-specific therapies is crucial. We aimed to investigate medication adherence to oral disease-specific medication and the impact on clinical outcome among patients with PAH or CTEPH to identify potentia...

Background The susceptibility to acute mountain sickness (AMS) in relation to sexual hormones in women remains elusive, partly because hormones could not be conveniently measured. We evaluated a novel kit for self-monitoring sexual hormones in women and recorded AMS incidence during high-altitude sojourns. Methods Two groups of healthy, premenopau...

Introduction: Lung cancer screening has increased the detection of peripheral pulmonary lesions (PPLs). Accurate diagnosis for therapy and prognosis is crucial but challenging. Our study compares the safety and efficacy of transbronchial cryobiopsy with two probe diameters and forceps biopsy. Methods: This single-centre, investigator-initiated, ope...

Pulmonary hypertension (PH) complicating interstitial lung diseases (ILDs) is critical for symptom burden and prognosis. The prevalence of PH varies according to ILDs subgroups and severities. Establishing the diagnosis of PH associated with ILDs (PH-ILDs) is complex due to overlapping symptoms, late clinical signs and poor diagnostic performance o...

Background Patients with chronic obstructive pulmonary disease (COPD) experience an increase in systolic pulmonary artery pressure (sPAP) when exposed to high altitude with an unclear acclimatization. We investigated the effects of acute ascent to 3100m on pulmonary hemodynamics of COPD-patients and their acclimatization during a three-day stay at...

Background Acclimatization to high altitudes over several weeks has not been extensively studied. Repeated physiological assessments were performed in healthy lowlanders staying at 3,100 m for 3 weeks. We hypothesized that acute exposure to 3,100 m results in hypoxemia, sleep-disordered breathing, and postural instability, while a 3-week acclimatiz...

Objectives The aim of this study was to compare the accuracy of photon-counting detector computed tomography (PCD-CT) iodine maps of the lung parenchyma with perfusion scintigraphy for detection and extent estimation of pulmonary perfusion defects. Materials and Methods This institutional review board–approved retrospective study included 26 subje...

OBJECTIVES Chronic thromboembolic pulmonary hypertension is a rare disease, characterized by delays in diagnosis and curative surgical treatment. After establishing a surgical pulmonary endarterectomy center in Switzerland and due to a historically low resection rate of 14%, a national multidisciplinary evaluation board was established in January 2...

Hematological and oncological diseases collectively affect a substantial number of patients. Pulmonary hypertension (PH) is recognized as a potential complication associated with these conditions, manifesting in various forms of PH and presenting with a range of symptoms. The complexity of PH in this context arises from its multifactorial etiology,...

Introduction In patients with chronic obstructive pulmonary disease (COPD), oxygen delivery to the heart may be impaired during travel at altitude. We assessed electrocardiogram (ECG)-derived signs of cardiac ischemia and the effects of preventive acetazolamide therapy in COPD patients traveling to high altitudes. Methods Patients with COPD [Globa...

Background This study investigated whether nocturnal oxygen therapy (NOT) improves next-day cerebrovascular function in lowlanders with COPD staying at moderate altitude. Methods This randomized, placebo-controlled crossover trial was performed in stable patients with moderate to severe COPD (FEV 1 /FVC <0.7 and FEV 1 30-80%predicted), living <800...

Häfliger, Alina, Aline Buergin, Laura C. Mayer, Maamed Mademilov, Mona Lichtblau, Talantbek Sooronbaev, Silvia Ulrich, Konrad E. Bloch, and Michael Furian. Sex-specific difference in health-related altitude-effects and their prevention by acetazolamide. Data from a randomized controlled trial. High Alt Med Biol. 00:00-00, 2024. Background: Women ar...

Background Hypoxic pulmonary vasoconstriction leads to an increase in pulmonary artery pressure (PAP) and potentially right heart failure in healthy individuals and patients with respiratory diseases. Previous studies in patients with chronic obstructive pulmonary disease (COPD) exposed to hypobaric hypoxia have shown an increase in PAP, while trad...

Objective To quantify the effect of two consecutive prolonged, intermittent exposures to high and very high altitudes on oxygen saturation (SpO2) and acute mountain sickness (AMS). Methods Healthy lowlanders (N=21), aged 18-30y, underwent two 7-day sojourns at the ALMA observatory, Chile (6hrs/day at 5050m, 18hrs/day at 2900m), separated by 1-week...

Background Limited data exist on the reliability, efficacy and safety of ultrasound-guided transbronchial cryobiopsy for suspicious mediastinal and hilar lesions. This study shares findings from implementing this method and compares the results with those of the standard endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)....

Background: The susceptibility to acute mountain sickness (AMS) in relation to sexual hormones in women remains elusive, partly because hormones could not be conveniently measured. We evaluated a novel kit for self-monitoring sexual hormones in women and recorded AMS incidence during high-altitude sojourns. Methods: Two groups of healthy, premenopa...

Background Exercise pulmonary hypertension (exercise PH) was defined by a mean pulmonary arterial pressure (mPAP)/cardiac output (CO) slope >3 mmHg·L ⁻¹ ·min ⁻¹ between rest and exercise in the 2022 ESC/ERS PH guidelines. However, large, multi-center studies on the prognostic relevance of exercise hemodynamics and its added value to resting hemodyn...

Background The acclimatization to high altitudes over several weeks is not extensively studied. Repeated physiological assessments were performed in healthy lowlanders staying at 3100m for 3 weeks. We hypothesized that over the course of 3 weeks, the arterial oxygen saturation (SpO2) improves and has favorable effects on psychomotor vigilance, post...

Introduction In patients with chronic obstructive pulmonary disease (COPD), oxygen delivery to the heart may be impaired during altitude travel. We assessed ECG-derived signs of cardiac ischemia, and effects of preventive acetazolamide therapy in COPD patients travelling to high altitude. Methods Patients with COPD, GOLD grade 2-3, mean±SD, FEV 1...

Objectives The aim of this study was to evaluate the feasibility and efficacy of chronic pulmonary thromboembolism assessment using photon-counting detector computed tomography (PCD-CT) iodine maps of the lung parenchyma. Materials and Methods This institutional review board–approved retrospective study included 83 subjects (49.4% male, aged 62.4...

Background/Aims The aim of this study was to investigate the acute effect of acetazolamide on pulmonary hemodynamics during exercise in patients with pulmonary vascular disease (PVD). Methods Patients with PVD diagnosed as pulmonary arterial or chronic thromboembolic pulmonary hypertension (PAH/CTEPH) underwent right heart catheterisation with hem...

Thrombotic microangiopathy (TMA) is defined by the typical triad of severe thrombocytopenia, hemolytic anemia and endorgan dysfunction and can be characterized by the pathophysiology of ischemia-inducing microthrombi in arterioles and capillaries possibly leading to severe organ dysfunction up to acutely life-threatening endorgan damage. In terms o...

Background In patients with chronic obstructive pulmonary disease (COPD), preventive treatment with acetazolamide reduces adverse health effects during altitude travel. We investigated whether preventive acetazolamide treatment modifies exercise performance in COPD patients going to high altitude. Methods In this randomized, double-blind trial, lo...

Current guidelines recommend oxygen (O2) supplementation in patients with pulmonary hypertension (PH), despite scarce data on long-term O2 therapy (LTOT). The aim of this prospective, randomized, controlled trial was to investigate the effect of LTOT in patients with precapillary PH on exercise capacity, clinical parameters and hemodynamics. Patien...

Purpose of review This review addresses the concern of the health effects associated with high-altitude living and chronic hypoxia with a focus on pulmonary hypertension. With an increasing global population residing at high altitudes, understanding these effects is crucial for public health interventions and clinical management. Recent findings R...

Over 80 Mio people worldwide live >2500 m, including at least as many patients with pulmonary vascular disease (PVD), defined as pulmonary arterial or chronic thromboembolic pulmonary hypertension (PAH/CTEPH), as elsewhere (estimated 0.1‰). Whether PVD patients living at high altitude have altered disease characteristics due to hypobaric hypoxia is...

Background Hypoxia is a trigger for sympathetic activation and autonomic cardiovascular dysfunction. Pulmonary vascular disease (PVD) is associated with hypoxemia, which increases with altitude. The aim was to investigate how exposure of patients with PVD to hypobaric hypoxia at altitude affects autonomic cardiovascular regulation. Methods In a ra...

Background Pulmonary arterial hypertension (PAH) is a devastating complication of systemic sclerosis (SSc), as it represents one of the leading causes of mortality. The DETECT algorithm is a screening tool to identify patients with SSc-PAH in the asymptomatic stage. This algorithm shows an optimal performance identifying almost all cases of PAH in...

Question addressed Patients with pulmonary vascular disease (PVD) often suffer from nocturnal hypoxemia, but also from sleep apnoea. Short-term use of acetazolamide increases ventilation due to metabolic acidosis and also reduces loop gain. We investigated whether prolonged use of acetazolamide improves sleep-disordered breathing in PVD. Methods I...

Pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension are the main precapillary forms of pulmonary hypertension (PH) summarized as pulmonary vascular diseases (PVD). PVDs are characterized by exertional dyspnoea and oxygen desaturation, and reduced quality of life and survival. Medical therapies improve life expectancy a...

Grimm, Mirjam, Lucie Ziegler, Annina Seglias, Maamed Mademilov, Kamila Magdieva, Gulzada Mirzalieva, Aijan Taalaibekova, Simone Suter, Simon R. Schneider, Fiona Zoller, Vera Bissig, Lukas Reinhard, Meret Bauer, Julian Müller, Tanja L. Ulrich, Arcangelo F. Carta, Patrick R. Bader, Konstantinos Bitos, Aurelia E. Reiser, Benoit Champigneulle, Damira A...

BACKGROUND Among patients with pulmonary arterial hypertension (PAH), acute vasoreactivity testing during right heart catheterization may identify acute vasoresponders, for whom treatment with high-dose calcium channel blockers (CCBs) is recommended. However, long-term outcomes in the current era remain largely unknown. We sought to evaluate the im...

Study Objectives To assess the diagnostic accuracy of a purpose-designed QTc-scoring algorithm versus the established hand-scoring in patients with chronic obstructive pulmonary disease (COPD) undergoing sleep studies. Methods We collected 62 overnight electrocardiogram (ECG) recordings in 28 COPD patients. QT-intervals corrected for heart rate (Q...

Objective To investigate the ventilatory and circulatory differences between eccentric (ECC) and concentric (CON) cycling exercise at submaximal, low-dose intensity from onset to end-exercise in healthy middle-aged participants. Design Randomized controlled crossover trial. Setting The participants underwent 1 ECC and 1 CON test according to step...

Objective To investigate the effect of a daylong exposure to high altitude on peak exercise capacity and safety in stable patients with pulmonary arterial and chronic thromboembolic pulmonary hypertension (PAH/CTEPH). Methods In a randomised controlled cross-over trial, stable patients with PAH or distal CTEPH without resting hypoxemia at low alti...

Shareable abstract (@ERSpublications) Key highlights in pulmonary vascular diseases from #ERSCongress 2023 include insights into disease modification in PAH and novel therapies, PH associated with lung disease, lung embolism and CTEPH https://bit.ly/476G6cT Abstract Pulmonary vascular diseases such as pulmonary embolism and pulmonary hypertension a...

Introduction: Acetazolamide (AZA) improves nocturnal and daytime blood oxygenation in patients with pulmonary vascular disease (PVD), defined as pulmonary arterial and distal chronic thromboembolic pulmonary hypertension (CTEPH), and may improve exercise performance. Methods: We investigated the effect of 5 weeks of AZA (250 mg bid) versus place...

Background: Hypoxia and old age impair postural control and may therefore enhance the risk of accidents. We investigated whether acetazolamide, the recommended drug for prevention of acute mountain sickness, may prevent altitude-induced deterioration of postural control in older persons. Methods: In this parallel-design trial, 95 healthy volunteers...

Ever since the second world symposium on pulmonary hypertension (PH) held in Evian, France, in 1998, PH has been classified into five major clinical groups. Group 5 PH includes a variety of distinct conditions with unclear and/or multifactorial underlying pathologies. Management of these patients is challenging as the number of patients within thes...

Zusammenfassung Im letzten Jahrzehnt hat sich aufgrund zunehmenden Alters bei Erstdiagnose eine Veränderung des klinischen Phänotyps mit einem vermehrten Vorkommen von Komorbiditäten bei der pulmonalarteriellen Hypertonie herausgebildet. Durch Clusteranalysen von Registerdaten wurden insbesondere ein kardialer, kardiopulmonaler und klassischer Phän...

Zusammenfassung Nicht selten sind Lungenerkrankungen und Hypoventilationssyndrome mit einer pulmonalen Hypertonie (PH) assoziiert. In den meisten Fällen liegt eine nicht schwere PH vor. Diese ist hämodynamisch definiert durch einen pulmonalarteriellen Mitteldruck (PAPm) > 20 mmHg, einen pulmonalarteriellen Verschlussdruck (PAWP) ≤ 15 mmHg und einen...

Zusammenfassung In der Neufassung der ESC/ERS-Leitlinien 2022 zur pulmonalen Hypertonie (PH) kam es zu wesentlichen Änderungen in der hämodynamischen Definition sowie zu einer weiteren Verfeinerung in der Klassifikation des Lungenhochdrucks. Als bedeutende Neuerung gilt die Einführung eines neuen Grenzwerts des mittleren pulmonalarteriellen Druckes...

Background: Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension (CTEPH) with accessible lesions. Breathing pure oxygen (hyperoxia) during right heart catheterization (RHC) allows for the calculation of the right-to-left shunt fraction (Qs/Qt). In the absence of intracardiac shun...

Introduction: This prospective cohort study assessed the effects of chronic hypoxaemia due to high-altitude residency on the cerebral tissue oxygenation (CTO) and cerebrovascular reactivity. Methods: Highlanders, born, raised, and currently living above 2,500 m, without cardiopulmonary disease, participated in a prospective cohort study from 2012 u...

Background Detection of pulmonary perfusion defects is the recommended approach for diagnosing chronic thromboembolic pulmonary hypertension (CTEPH). This is currently achieved in a clinical setting using scintigraphy. Phase‐resolved functional lung (PREFUL) magnetic resonance imaging (MRI) is an alternative technique for evaluating regional ventil...

With an estimated prevalence of around 1%, pulmonary hypertension (PH) presents a relevant burden worldwide. In this review, we aim to give an overview of the novelties from the revised European Society of Cardiology (ESC) /European Respiratory Society (ERS) guidelines for the diagnosis and treatment of PH and their implication for the everyday cli...

Background The course of pulmonary arterial wedge pressure (PAWP) during exercise in patients with pulmonary arterial or chronic thromboembolic pulmonary hypertension (PAH/CTEPH), further abbreviated as pulmonary vascular disease (PVD) is still unknown. The aim of the study was to describe the PAWP during exercise in patients with PVD. Methods In...

Background Amongst the millions of travelers to high altitude worldwide are many with chronic obstructive pulmonary disease (COPD), but data regarding the effects of acute exposure to altitude on exercise performance are limited. The current study investigated how acute exposure to moderate altitude influences exercise performance in COPD patients,...

Background: Asthma rehabilitation at high altitude is common. Little is known about the acute and subacute cardiopulmonary acclimatization to high altitude in middle-aged asthmatics without other comorbidities. Methods: In this prospective study in lowlander subjects with mostly mild asthma who revealed an asthma control questionnaire score >0.75 a...

Objectives: Pulmonary arterial hypertension (PAH) occurs in various connective tissue diseases (CTDs). We sought to assess contemporary treatment patterns and survival of patients with various forms of CTD-PAH. Methods: We analysed data from COMPERA, a European pulmonary hypertension registry, to describe treatment strategies and survival in pat...

Background and aim Cardiomyopathy has become an important life-limiting factor since survival in Duchenne muscular dystrophy (DMD) has greatly increased with long-term ventilation and cough assistance. The aim was to investigate the association between impaired left ventricular ejection fraction (LVEF) and survival. Methods In a >20-year observati...

Background Pulmonary hypertension (PH) is a complex clinical condition and left heart disease is the leading cause. Little is known about the epidemiology and prognosis of combined post- and precapillary PH (CpcPH). Methods This retrospective analysis of the Swiss PH Registry included incident patients with CpcPH registered from 01/2001 to 06/2019...

Background Chronic Thromboembolic Pulmonary Hypertension (CTEPH) is a rare, debilitating disease characterized by pathological changes that obstruct both sides of the pulmonary arteries (PA). The underlying pathophysiology is poorly understood. Aims Trying to understand the possible contribution of microRNAs to CTEPH pathophysiology, we here analy...