Long-Haul Post-COVID-19 Symptoms Presenting as a Variant of Postural Orthostatic Tachycardia Syndrome: The Swedish Experience

Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment

OBJECTIVE

To report the prevalence and severity of nonpelvic symptoms for patients with venous-origin chronic pelvic pain (VO-CPP) and to describe outcomes after pelvic vein stenting and embolization.

METHODS

We retrospectively reviewed outcomes of 45 women with VO-CPP who underwent treatment with iliac vein stenting and/or embolization. Patients completed symptom-severity questionnaires before and after treatment that assessed for pelvic pain, and multiple other symptoms, including brain fog, anxiety, depression, musculoskeletal pain, fatigue, migraines and more.

RESULTS

Patient age ranged from 18 to 65 years. The prevalence of common symptoms was as follows: migraines, 69%; brain fog, 76%; anxiety attacks, 58%; excess sweating, 64%; hip pain, 73%; diarrhea, 62%; constipation, 76%; and abdominal bloating, 82%. After treatment, most symptom scores improved by more than 50%; exceptions were excessive sweating (41% improvement) and bloating (47% improvement). Prevalence of individual symptoms that bundle into POTS ranged from 29% to 76%, where symptom improvement ranged from 23% to 59% after treatment. Overlapping individual symptoms characteristic of fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) were present in 64% to 82% of patients and all improved by 49% to 63% after treatment.

CONCLUSIONS

Pelvic venous flow abnormality is linked causally to a spectrum of interrelated symptoms, of which many can be bundled into named syndromes of unknown cause. With catheter- based treatment of pelvic venous pooling, nonpelvic symptom and syndrome scores improved.

Cardiovascular autonomic dysfunction in post-COVID-19 syndrome: a major health-care burden

Cardiovascular autonomic dysfunction (CVAD) is a malfunction of the cardiovascular system caused by deranged autonomic control of circulatory homeostasis. CVAD is an important component of post-COVID-19 syndrome, also termed long COVID, and might affect one-third of highly symptomatic patients with COVID-19. The effects of CVAD can be seen at both the whole-body level, with impairment of heart rate and blood pressure control, and in specific body regions, typically manifesting as microvascular dysfunction. Many severely affected patients with long COVID meet the diagnostic criteria for two common presentations of CVAD: postural orthostatic tachycardia syndrome and inappropriate sinus tachycardia. CVAD can also manifest as disorders associated with hypotension, such as orthostatic or postprandial hypotension, and recurrent reflex syncope. Advances in research, accelerated by the COVID-19 pandemic, have identified new potential pathophysiological mechanisms, diagnostic methods and therapeutic targets in CVAD. For clinicians who daily see patients with CVAD, knowledge of its symptomatology, detection and appropriate management is more important than ever. In this Review, we define CVAD and its major forms that are encountered in post-COVID-19 syndrome, describe possible CVAD aetiologies, and discuss how CVAD, as a component of post-COVID-19 syndrome, can be diagnosed and managed. Moreover, we outline directions for future research to discover more efficient ways to cope with this prevalent and long-lasting condition.

Long COVID in Children, Adults, and Vulnerable Populations: A Comprehensive Overview for an Integrated Approach

Long COVID affects both children and adults, including subjects who experienced severe, mild, or even asymptomatic SARS-CoV-2 infection. We have provided a comprehensive overview of the incidence, clinical characteristics, risk factors, and outcomes of persistent COVID-19 symptoms in both children and adults, encompassing vulnerable populations, such as pregnant women and oncological patients. Our objective is to emphasize the critical significance of adopting an integrated approach for the early detection and appropriate management of long COVID. The incidence and severity of long COVID symptoms can have a significant impact on the quality of life of patients and the course of disease in the case of pre-existing pathologies. Particularly, in fragile and vulnerable patients, the presence of PASC is related to significantly worse survival, independent from pre-existing vulnerabilities and treatment. It is important try to achieve an early recognition and management. Various mechanisms are implicated, resulting in a wide range of clinical presentations. Understanding the specific mechanisms and risk factors involved in long COVID is crucial for tailoring effective interventions and support strategies. Management approaches involve comprehensive biopsychosocial assessments and treatment of symptoms and comorbidities, such as autonomic dysfunction, as well as multidisciplinary rehabilitation. The overall course of long COVID is one of gradual improvement, with recovery observed in the majority, though not all, of patients. As the research on long-COVID continues to evolve, ongoing studies are likely to shed more light on the intricate relationship between chronic diseases, such as oncological status, cardiovascular diseases, psychiatric disorders, and the persistent effects of SARS-CoV-2 infection. This information could guide healthcare providers, researchers, and policymakers in developing targeted interventions.

Multidisciplinary Management Strategies for Long COVID: A Narrative Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused millions of infections to date and has led to a worldwide pandemic. Most patients had a complete recovery from the acute infection, however, a large number of the affected individuals experienced symptoms that persisted more than 3 months after diagnosis. These symptoms most commonly include fatigue, memory difficulties, brain fog, dyspnea, cough, and other less common ones such as headache, chest pain, paresthesias, mood changes, muscle pain, and weakness, skin rashes, and cardiac, endocrine, renal and hepatic manifestations. The treatment of this syndrome remains challenging. A multidisciplinary approach to address combinations of symptoms affecting multiple organ systems has been widely adopted. This narrative review aims to bridge the gap surrounding the broad treatment approaches by providing an overview of multidisciplinary management strategies for the most common long COVID conditions.

Postural orthostatic tachycardia syndrome and other autonomic dysfunctions following COVID-19: Incidence, characteristics, and associated factors

Background

Long-COVID syndrome has become a new health concern. Many major clinical centers have experienced more patients with symptoms suggestive of autonomic dysfunction, especially postural orthostatic tachycardia syndrome (POTS) following COVID-19. However, there is a lack of information regarding the incidence and associated factors in Asian population.

Methods

A retro-prospective study was conducted to evaluate patients with symptoms suggestive of POTS or other autonomic dysfunctions. These symptoms last at least 3 months after PCR-proven COVID-19. Exclusion criteria were age under 18 years old, pregnancy, and pre-COVID-19 autonomic dysfunction symptoms. Patients with a symptom severity score greater than two were assessed with blood tests, 24-h Holter, 24-h ambulatory blood pressure, echocardiogram, and head-up tilt table (HUTT).

Results

Seven hundred ninety-three patients were interviewed at 146 ± 37 days after COVID-19. The majority of patients were middle-aged females (53%). Of those, 15 patients had the symptom severity score greater than 2. Out of those 15 patients, 12 had positive HUTT (1 demonstrating POTS, 10 neurocardiogenic syncope, and 1 orthostatic hypotension). Among those with positive HUTT patients, C-reactive protein (CRP) was significantly higher (OR 1.01; p-value 0.041). Fatigue and dyspnea on exertion were the two most complaint symptoms.

Conclusions

This study shows the incidence of autonomic dysfunction and POTS is 1.5% (12/793) and 0.1% POTS (1/793), respectively, in a primary care setting (among general post-COVID-19 patients). The most common symptoms for these patients were fatigue and dyspnea.

Cardiovascular dysautonomia in postacute sequelae of SARS-CoV-2 infection

Coronavirus disease 2019 (COVID-19) has led to a worldwide pandemic that continues to transform but will not go away. Cardiovascular dysautonomia in postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection has led to persistent symptoms in a large number of patients. Here, we define the condition and its associated symptoms as well as potential mechanisms responsible. We provide a careful and complete overview of the topic addressing novel studies and a generalized approach to the management of individuals with this complex and potentially debilitating problem. We also discuss future research directions and the important knowledge gaps to be addressed in ongoing and planned studies.

Gut microbiota composition is altered in postural orthostatic tachycardia syndrome and post-acute COVID-19 syndrome

Postural Orthostatic Tachycardia Syndrome (POTS) reflects an autonomic dysfunction, which can occur as a complication to COVID-19. Our aim was to examine gastrointestinal symptoms and gut microbiota composition in patients with POTS and post-acute COVID-19 syndrome (PACS), compared with controls. POTS patients (n = 27), PACS patients (n = 32) and controls (n = 39) delivered fecal samples and completed a 4-day food diary, irritable bowel syndrome-severity scoring system (IBS-SSS), and visual analog scale for IBS (VAS-IBS). A total of 98 DNA aliquots were sequenced to an average depth of 28.3 million (M) read pairs (Illumina 2 × 150 PE) per sample. Diversity and taxonomic levels of the microbiome, as well as functional abundances were calculated for POTS and PACS groups, then compared with controls. There were several differences in taxonomic composition between POTS and controls, whereas only the abundance of Ascomycota and Firmicutes differed between PACS and controls. The clinical variables total IBS-SSS, fatigue, and bloating and flatulence significantly correlated with multiple individual taxa abundances, alpha diversity, and functional abundances. We conclude that POTS, and to a less extent PACS, are associated with differences in gut microbiota composition in diversity and at several taxonomic levels. Clinical symptoms are correlated with both alpha diversity and taxonomic and functional abundances.

Cardiovascular effects of the post-COVID-19 condition

Throughout the COVID-19 pandemic, the new clinical entity of the post-COVID-19 condition, defined as a multisystemic condition of persistent symptoms following resolution of an acute severe acute respiratory syndrome coronavirus 2 infection, has emerged as an important area of clinical focus. While this syndrome spans multiple organ systems, cardiovascular complications are often the most prominent features. These include, but are not limited to, myocardial injury, heart failure, arrhythmias, vascular injury/thrombosis and dysautonomia. As the number of individuals with the post-COVID-19 condition continues to climb and overwhelm medical systems, summarizing existing information and knowledge gaps in the complex cardiovascular effects of the post-COVID-19 condition has become critical for patient care. In this Review, we explore the current state of knowledge of the post-COVID-19 condition and identify areas where additional research is warranted. This will provide a framework for better understanding the cardiovascular manifestations of the post-COVID-19 condition with a focus on pathophysiology, diagnosis and management.

The Long-COVID autonomic syndrome in hospitalized patients: A one-year prospective cohort study

Long-COVID syndrome is characterized by fatigue, orthostatic intolerance, tachycardia, pain, memory difficulties, and brain fog, which may be associated with autonomic nervous system abnormalities. We aimed to evaluate the short and long-term course of COVID-19 autonomic symptoms and quality of life (QoL) after SARS-CoV-2 infection through a one-year follow-up combined with validated questionnaires. Additionally, we aimed to identify patients with worsening autonomic symptoms at 6 and 12 months by dividing the patient cohort into two sub-groups: the Post-COVID healed Control sub-group (total score<16.4) and the Long-COVID autonomic syndrome sub-group (total score>16.4). This prospective cohort studied 112 SARS-CoV-2 positive patients discharged from Humanitas Research Hospital between January and March 2021. Autonomic symptoms and QoL were assessed using the composite autonomic symptom scale 31 (COMPASS-31) and Short Form Health Survey (SF-36) questionnaires at various time points: before SARS-CoV-2 infection (PRE), at hospital discharge (T0), and at 1 (T1), 3 (T3), 6 (T6), and 12 (T12) months of follow-up. COMPASS-31 total score, Orthostatic Intolerance and Gastrointestinal function indices, QoL, physical functioning, pain, and fatigue scores worsened at T0 compared to PRE but progressively improved at T1 and T3, reflecting the acute phase of COVID-19. Unexpectedly, these indices worsened at T6 and T12 compared to T3. Subgroup analysis revealed that 47% of patients experienced worsening autonomic symptoms at T6 and T12, indicating Long-COVID autonomic syndrome. Early rehabilitative and pharmacological therapy is recommended for patients at the T1 and T3 stages after SARS-CoV-2 infection to minimize the risk of developing long-term autonomic syndrome.

Possible Role of Fibrinaloid Microclots in Postural Orthostatic Tachycardia Syndrome (POTS): Focus on Long COVID

Postural orthostatic tachycardia syndrome (POTS) is a common accompaniment of a variety of chronic, inflammatory diseases, including long COVID, as are small, insoluble, 'fibrinaloid' microclots. We here develop the argument, with accompanying evidence, that fibrinaloid microclots, through their ability to block the flow of blood through microcapillaries and thus cause tissue hypoxia, are not simply correlated with but in fact, by preceding it, may be a chief intermediary cause of POTS, in which tachycardia is simply the body's exaggerated 'physiological' response to hypoxia. Similar reasoning accounts for the symptoms bundled under the term 'fatigue'. Amyloids are known to be membrane disruptors, and when their targets are nerve membranes, this can explain neurotoxicity and hence the autonomic nervous system dysfunction that contributes to POTS. Taken together as a system view, we indicate that fibrinaloid microclots can serve to link POTS and fatigue in long COVID in a manner that is at once both mechanistic and explanatory. This has clear implications for the treatment of such diseases.

Treatment of long COVID complicated by postural orthostatic tachycardia syndrome-Case series research

Background

Coronavirus disease 2019 (COVID-19) sequelae, also known as long COVID, can present with various symptoms. Among these symptoms, autonomic dysregulation, particularly postural orthostatic tachycardia syndrome (POTS), should be evaluated. However, previous studies on the treatment of POTS complicated by COVID-19 are lacking. Therefore, this study aimed to investigate the treatment course of long COVID complicated by POTS.

Methods

The medical records of patients who complained of fatigue and met the criteria for POTS diagnosis were reviewed. We evaluated the treatment days, methods and changes in fatigue score, changes in heart rate on the Schellong test, and social situation at the first and last visits.

Results

Thirty-two patients with long COVID complicated by POTS were followed up (16 males; median age: 28 years). The follow-up period was 159 days, and the interval between COVID-19 onset and initial hospital attendance was 97 days. Some patients responded to β-blocker therapy. Many patients had psychiatric symptoms that required psychiatric intervention and selective serotonin reuptake inhibitor prescription. Changes in heart rate, performance status, and employment/education status improved from the first to the last visit. These outcomes were believed to be because of the effects of various treatment interventions and spontaneous improvements.

Conclusions

Our study suggests that the condition of 94% of patients with POTS complicated by long COVID will improve within 159 days. Therefore, POTS evaluation should be considered when patients with long COVID complain of fatigue, and attention should be paid to psychological symptoms and the social context.

Balancing the value and risk of exercise-based therapy post-COVID-19: a narrative review

Coronavirus disease 2019 (COVID-19) can lead to ongoing symptoms such as breathlessness, fatigue and muscle pain, which can have a substantial impact on an individual. Exercise-based rehabilitation programmes have proven beneficial in many long-term conditions that share similar symptoms. These programmes have favourably influenced breathlessness, fatigue and pain, while also increasing functional capacity. Exercise-based rehabilitation may benefit those with ongoing symptoms following COVID-19. However, some precautions may be necessary prior to embarking on an exercise programme. Areas of concern include ongoing complex lung pathologies, such as fibrosis, cardiovascular abnormalities and fatigue, and concerns regarding post-exertional symptom exacerbation. This article addresses these concerns and proposes that an individually prescribed, symptom-titrated exercise-based intervention may be of value to individuals following infection with severe acute respiratory syndrome coronavirus 2.

Autonomic Manifestations of Long-COVID Syndrome

PURPOSE OF REVIEW

Long-COVID is a novel condition emerging from the COVID-19 pandemic. Long-COVID is characterized by symptoms commonly seen in autonomic disorders including fatigue, brain fog, light-headedness, and palpitations. This article will critically evaluate recent findings and studies on Long-COVID and its physiological autonomic manifestations.

RECENT FINDINGS

Studies have reported on the prevalence of different symptoms and autonomic disorders in Long-COVID cohorts. Autonomic nervous system function, including both the parasympathetic and sympathetic limbs, has been studied using different testing techniques in Long-COVID patients. While numerous mechanisms may contribute to Long-COVID autonomic pathophysiology, it is currently unclear which ones lead to a Long-COVID presentation. To date, studies have not tested treatment options for autonomic disorders in Long-COVID patients. Long-COVID is associated with autonomic abnormalities. There is a high prevalence of clinical autonomic disorders among Long-COVID patients, with limited knowledge of the underlying mechanisms and the effectiveness of treatment options.

Recognizing postural orthostatic tachycardia syndrome in primary care

ABSTRACT

Postural orthostatic tachycardia syndrome (POTS) is a complex autonomic disorder characterized by abnormal tachycardia on standing. This disorder predominantly affects young women, with a peak incidence between ages 20 and 30 years. POTS often is associated with a variety of symptoms, including dizziness, palpitations, fatigue, generalized weakness, anxiety, and exercise intolerance, which can significantly impair patient quality of life. Primary care providers (PCPs) often are the first healthcare professionals to whom patients present. This article provides an overview of POTS, including diagnostic criteria and the importance of a thorough clinical evaluation to rule out other causes of symptoms. PCPs play a critical role in the comprehensive approach to care, involving patient education, lifestyle modifications, and treatment to improve outcomes and enhance patient quality of life.

Pooled rates and demographics of POTS following SARS-CoV-2 infection versus COVID-19 vaccination: Systematic review and meta-analysis

PURPOSE

To address recent concerns of postural orthostatic tachycardia syndrome (POTS) occurring after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) vaccination.

METHODS

We searched PubMed, Web of Science, and Scopus as of 1st June 2023. We performed a systematic review and meta-analysis of pooled POTS rate in SARS-CoV-2-infected and COVID-19-vaccinated groups from epidemiological studies, followed by subgroup analyses by characteristic. Meta-analysis of risk ratio was conducted to compare POTS rate in infected versus uninfected groups. Meta-analysis of demographics was also performed to compare cases of post-infection and post-vaccination POTS from case reports and series.

RESULTS

We estimated the pooled POTS rate of 107.75 (95 % CI: 9.73 to 273.52) and 3.94 (95 % CI: 0 to 16.39) cases per 10,000 (i.e., 1.08 % and 0.039 %) in infected and vaccinated individuals based on 5 and 2 studies, respectively. Meta-regression revealed age as a significant variable influencing 86.2 % variance of the pooled POTS rate in infected population (P < 0.05). Moreover, POTS was 2.12-fold more likely to occur in infected than uninfected individuals (RR = 2.12, 95 % CI: 1.71 to 2.62, P < 0.001). Meta-analyzed demographics for cases of post-infection (n = 43) and post-vaccination (n = 17) POTS found no significant differences in several variables between groups, except that the time from exposure to symptom onset was shorter for cases of post-vaccination POTS (P < 0.05).

CONCLUSION

Although evidence is limited for post-vaccination POTS, our study showed that POTS occur more frequently following SARS-CoV-2 infection than COVID-19 vaccination.

SGLT2 Inhibitors in Long COVID Syndrome: Is There a Potential Role?

The coronavirus disease (COVID)-19 has turned into a pandemic causing a global public health crisis. While acute COVID-19 mainly affects the respiratory system and can cause acute respiratory distress syndrome, an association with persistent inflammatory stress affecting different organ systems has been elucidated in long COVID syndrome (LCS). Increased severity and mortality rates have been reported due to cardiophysiological and metabolic systemic disorders as well as multiorgan failure in COVID-19, additionally accompanied by chronic dyspnea and fatigue in LCS. Hence, novel therapies have been tested to improve the outcomes of LCS of which one potential candidate might be sodium-glucose cotransporter 2 (SGLT2) inhibitors. The aim of this narrative review was to discuss rationales for investigating SGLT2 inhibitor therapy in people suffering from LCS. In this regard, we discuss their potential positive effects-next to the well described "cardio-renal-metabolic" conditions-with a focus on potential anti-inflammatory and beneficial systemic effects in LCS. However, potential beneficial as well as potential disadvantageous effects of SGLT2 inhibitors on the prevalence and long-term outcomes of COVID-19 will need to be established in ongoing research.

Dysregulations in hemostasis, metabolism, immune response, and angiogenesis in post-acute COVID-19 syndrome with and without postural orthostatic tachycardia syndrome: a multi-omic profiling study

Post-acute COVID-19 (PACS) are associated with cardiovascular dysfunction, especially postural orthostatic tachycardia syndrome (POTS). Patients with PACS, both in the absence or presence of POTS, exhibit a wide range of persisting symptoms long after the acute infection. Some of these symptoms may stem from alterations in cardiovascular homeostasis, but the exact mechanisms are poorly understood. The aim of this study was to provide a broad molecular characterization of patients with PACS with (PACS + POTS) and without (PACS-POTS) POTS compared to healthy subjects, including a broad proteomic characterization with a focus on plasma cardiometabolic proteins, quantification of cytokines/chemokines and determination of plasma sphingolipid levels. Twenty-one healthy subjects without a prior COVID-19 infection (mean age 43 years, 95% females), 20 non-hospitalized patients with PACS + POTS (mean age 39 years, 95% females) and 22 non-hospitalized patients with PACS-POTS (mean age 44 years, 100% females) were studied. PACS patients were non-hospitalized and recruited ≈18 months after the acute infection. Cardiometabolic proteomic analyses revealed a dysregulation of ≈200 out of 700 analyzed proteins in both PACS groups vs. healthy subjects with the majority (> 90%) being upregulated. There was a large overlap (> 90%) with no major differences between the PACS groups. Gene ontology enrichment analysis revealed alterations in hemostasis/coagulation, metabolism, immune responses, and angiogenesis in PACS vs. healthy controls. Furthermore, 11 out of 33 cytokines/chemokines were significantly upregulated both in PACS + POTS and PACS-POTS vs. healthy controls and none of the cytokines were downregulated. There were no differences in between the PACS groups in the cytokine levels. Lastly, 16 and 19 out of 88 sphingolipids were significantly dysregulated in PACS + POTS and PACS-POTS, respectively, compared to controls with no differences between the groups. Collectively, these observations suggest a clear and distinct dysregulation in the proteome, cytokines/chemokines, and sphingolipid levels in PACS patients compared to healthy subjects without any clear signature associated with POTS. This enhances our understanding and might pave the way for future experimental and clinical investigations to elucidate and/or target resolution of inflammation and micro-clots and restore the hemostasis and immunity in PACS.

Evaluation and treatment approaches for neurological post-acute sequelae of COVID-19: A consensus statement and scoping review from the global COVID-19 neuro research coalition

Post-acute neurological sequelae of COVID-19 affect millions of people worldwide, yet little data is available to guide treatment strategies for the most common symptoms. We conducted a scoping review of PubMed/Medline from 1/1/2020-4/1/2023 to identify studies addressing diagnosis and treatment of the most common post-acute neurological sequelae of COVID-19 including: cognitive impairment, sleep disorders, headache, dizziness/lightheadedness, fatigue, weakness, numbness/pain, anxiety, depression and post-traumatic stress disorder. Utilizing the available literature and international disease-specific society guidelines, we constructed symptom-based differential diagnoses, evaluation and management paradigms. This pragmatic, evidence-based consensus document may serve as a guide for a holistic approach to post-COVID neurological care and will complement future clinical trials by outlining best practices in the evaluation and treatment of post-acute neurological signs/symptoms.

Dysautonomia, but Not Cardiac Dysfunction, Is Common in a Cohort of Individuals with Long COVID

Despite the prevalence of dysautonomia in people with Long COVID, it is currently unknown whether Long COVID dysautonomia is routinely accompanied by structural or functional cardiac alterations. In this retrospective observational study, the presence of echocardiographic abnormalities was assessed. Left ventricular (LV) chamber sizes were correlated to diagnostic categories and symptoms via standardized patient-reported outcome (PRO) questionnaires. A total of 203 individuals with Long COVID without pre-existing cardiac disease and with available echocardiograms were included (mean age, 45 years; 67% female). Overall, symptoms and PRO scores for fatigue, breathlessness, quality of life, disability, anxiety and depression were not different between those classified with post-COVID dysautonomia (PCD, 22%) and those unclassified (78%). An LV internal diameter at an end-diastole z score < -2 was observed in 33 (16.5%) individuals, and stroke volume (SV) was lower in the PCD vs. unclassified subgroup (51.6 vs. 59.2 mL, 95% C.I. 47.1-56.1 vs. 56.2-62.3). LV end-diastolic volume (mean diff. (95% CI) -13 [-1--26] mL, p = 0.04) and SV (-10 [-1--20] mL, p = 0.03) were smaller in those individuals reporting a reduction in physical activity post-COVID-19 infection, and smaller LVMI was weakly correlated with worse fatigue (r = 0.23, p = 0.02). The majority of individuals with Long COVID report shared symptoms and did not demonstrate cardiac dysfunction on echocardiography.

Unmasking Pandemic Echoes: An In-Depth Review of Long COVID's Unabated Cardiovascular Consequences beyond 2020

At the beginning of 2020, coronavirus disease 2019 (COVID-19) emerged as a new pandemic, leading to a worldwide health crisis and overwhelming healthcare systems due to high numbers of hospital admissions, insufficient resources, and a lack of standardized therapeutic protocols. Multiple genetic variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been detected since its first public declaration in 2020, some of them being considered variants of concern (VOCs) corresponding to several pandemic waves. Nevertheless, a growing number of COVID-19 patients are continuously discharged from hospitals, remaining symptomatic even months after their first episode of COVID-19 infection. Long COVID-19 or 'post-acute COVID-19 syndrome' emerged as the new pandemic, being characterized by a high variability of clinical manifestations ranging from cardiorespiratory and neurological symptoms such as chest pain, exertional dyspnoea or cognitive disturbance to psychological disturbances, e.g., depression, anxiety or sleep disturbance with a crucial impact on patients' quality of life. Moreover, Long COVID is viewed as a new cardiovascular risk factor capable of modifying the trajectory of current and future cardiovascular diseases, altering the patients' prognosis. Therefore, in this review we address the current definitions of Long COVID and its pathophysiology, with a focus on cardiovascular manifestations. Furthermore, we aim to review the mechanisms of acute and chronic cardiac injury and the variety of cardiovascular sequelae observed in recovered COVID-19 patients, in addition to the potential role of Long COVID clinics in the medical management of this new condition. We will further address the role of future research for a better understanding of the actual impact of Long COVID and future therapeutic directions.

Cardiorespiratory dysautonomia in post-COVID-19 condition: Manifestations, mechanisms and management

A significant proportion of COVID-19 patients experience debilitating symptoms for months after the acute infection. According to recent estimates, approximately 1 out of 10 COVID-19 convalescents reports persistent health issues more than 3 months after initial recovery. This 'post-COVID-19 condition' may include a large variety of symptoms from almost all domains and organs, and for some patients it may mean prolonged sick-leave, homestay and strongly limited activities of daily life. In this narrative review, we focus on the symptoms and signs of post-COVID-19 condition in adults - particularly those associated with cardiovascular and respiratory systems, such as postural orthostatic tachycardia syndrome or airway disorders - and explore the evidence for chronic autonomic dysfunction as a potential underlying mechanism. The most plausible hypotheses regarding cellular and molecular mechanisms behind the wide spectrum of observed symptoms - such as lingering viruses, persistent inflammation, impairment in oxygen sensing systems and circulating antibodies directed to blood pressure regulatory components - are discussed. In addition, an overview of currently available pharmacological and non-pharmacological treatment options is presented.

Importance of resting heart rate

Resting heart rate is a determinant of cardiac output and physiological homeostasis. Although a simple, but critical, parameter, this vital sign predicts adverse outcomes, including mortality, and development of diseases in otherwise normal and healthy individuals. Temporal changes in heart rate can have valuable predictive capabilities. Heart rate can reflect disease severity in patients with various medical conditions. While heart rate represents a compilation of physiological inputs, including sympathetic and parasympathetic tone, aside from the underlying intrinsic sinus rate, how resting heart rate affects outcomes is uncertain. Mechanisms relating resting heart rate to outcomes may be disease-dependent but why resting heart rate in otherwise healthy, normal individuals affects outcomes remains obscure. For specific conditions, physiologically appropriate heart rate reductions may improve outcomes. However, to date, in the normal population, evidence that interventions aimed at reducing heart rate improves outcomes remains undefined. Emerging data suggest that reduction in heart rate via vagal activation and/or sympathetic inhibition is propitious.

Impaired parasympathetic function in long-COVID postural orthostatic tachycardia syndrome - a case-control study

PURPOSE

Eighty percent of patients infected by SARS-CoV-2 report persistence of one symptom beyond the 4-week convalescent period. Those with orthostatic tachycardia and orthostatic symptoms mimicking postural tachycardia syndrome, they are defined as Long-COVID POTS [LCP]. This case-control study investigated potential differences in autonomic cardiovascular regulation between LCP patients and healthy controls.

METHODS

Thirteen LCP and 16 healthy controls, all female subjects, were studied without medications. Continuous blood pressure and ECG were recorded during orthostatic stress test, respiratory sinus arrhythmia, and Valsalva maneuver. Time domain and power spectral analysis of heart rate [HR] and systolic blood pressure [SBP] variability were computed characterizing cardiac autonomic control and sympathetic peripheral vasoconstriction.

RESULTS

LCP had higher deltaHR (+ 40 ± 6 vs. + 21 ± 3 bpm, p = 0.004) and deltaSBP (+ 8 ± 4 vs. -1 ± 2 mmHg, p = 0.04) upon standing; 47% had impaired Valsalva maneuver ratio compared with 6.2% in controls (p = 0.01). Spectral analysis revealed that LCP had lower RMSSD (32.1 ± 4.6 vs. 48.9 ± 6.8 ms, p = 0.04) and HFRRI, both in absolute (349 ± 105 vs. 851 ± 253ms2, p = 0.03) and normalized units (32 ± 4 vs. 46 ± 4 n.u., p = 0.02). LFSBP was similar between groups.

CONCLUSIONS

LCP have reduced cardiovagal modulation, but normal sympathetic cardiac and vasoconstrictive functions. Impaired parasympathetic function may contribute to the pathogenesis of Long-COVID POTS syndrome.

Cardiovascular autonomic dysfunction in "Long COVID": pathophysiology, heart rate variability, and inflammatory markers

Long COVID is characterized by persistent signs and symptoms that continue or develop for more than 4 weeks after acute COVID-19 infection. Patients with Long COVID experience a cardiovascular autonomic imbalance known as dysautonomia. However, the underlying autonomic pathophysiological mechanisms behind this remain unclear. Current hypotheses include neurotropism, cytokine storms, and inflammatory persistence. Certain immunological factors indicate autoimmune dysfunction, which can be used to identify patients at a higher risk of Long COVID. Heart rate variability can indicate autonomic imbalances in individuals suffering from Long COVID, and measurement is a non-invasive and low-cost method for assessing cardiovascular autonomic modulation. Additionally, biochemical inflammatory markers are used for diagnosing and monitoring Long COVID. These inflammatory markers can be used to improve the understanding of the mechanisms driving the inflammatory response and its effects on the sympathetic and parasympathetic pathways of the autonomic nervous system. Autonomic imbalances in patients with Long COVID may result in lower heart rate variability, impaired vagal activity, and substantial sympathovagal imbalance. New research on this subject must be encouraged to enhance the understanding of the long-term risks that cardiovascular autonomic imbalances can cause in individuals with Long COVID.

Postural orthostatic tachycardia syndrome and other related dysautonomic disorders after SARS-CoV-2 infection and after COVID-19 messenger RNA vaccination

The COVID-19 pandemic has caused a challenge for our society due to the post-acute sequelae of the disease. Persistent symptoms and long-term multiorgan complications, known as post-acute COVID-19 syndrome, can occur beyond 4 weeks from the onset of the COVID-19 infection. Postural orthostatic tachycardia syndrome (POTS) is considered a variety of dysautonomia, which is characterized by chronic symptoms that occur with standing and a sustained increase in heart rate, without orthostatic hypotension. POTS can lead to debilitating symptoms, significant disability, and impaired quality of life. In this narrative review, the etiopathogenic basis, epidemiology, clinical manifestations, diagnosis, treatment, prognosis, and socioeconomic impact of POTS, as well as other related dysautonomic disorders, after COVID-19 infection and SARS-CoV-2 postvaccination, were discussed. After a search conducted in March 2023, a total of 89 relevant articles were selected from the PubMed, Google Scholar, and Web of Science databases. The review highlights the importance of recognizing and managing POTS after COVID-19 infection and vaccination, and the approach to autonomic disorders should be known by all specialists in different medical areas. The diagnosis of POTS requires a comprehensive clinical assessment, including a detailed medical history, physical examination, orthostatic vital signs, and autonomic function tests. The treatment of POTS after COVID-19 infection or vaccination is mainly focused on lifestyle modifications, such as increased fluid and salt intake, exercise, and graduated compression stockings. Pharmacotherapy, such as beta-blockers, fludrocortisone, midodrine, and ivabradine, may also be used in selected cases. Further research is needed to understand the underlying mechanisms, risk factors, and optimal treatment strategies for this complication.

Post-COVID-19 Syndrome and Related Dysautonomia: Reduced Quality of Life, Increased Anxiety and Manifestation of Depressive Symptoms: Evidence from Greece

Background

Post-COVID-19 syndrome affects a significant number of SARS-CoV-2 infected individuals, even in asymptomatic cases causing several neurological and neuropsychiatric symptoms and signs.

Materials and Methods

An online cross-sectional study with a convenience sample was conducted in Greece from November 2022 to January 2023. We measured the demographic and clinical characteristics of patients with post-COVID-19 dysautonomia in terms of the quality of life with the EQ-5D-3L, and anxiety and depressive symptoms by employing Patient Health Questionnaire-4.

Results

The study population included 122 patients with post-COVID-19 syndrome. One out of four patients (27.8%) manifested post-COVID-19 dysautonomia, while the mean duration of COVID-19 symptoms was 11.6 months. Anxiety and depressive symptoms were worse after the post-COVID-19 syndrome (p<0.001 in both cases). A statistically significant reduction in quality of life was observed among patients after the post-COVID-19 syndrome (p<0.001 for both EQ-5D-3L index value and EQ-5D-3L VAS). Post-COVID-19 dysautonomia increased depression symptoms after developing the post-COVID-19 syndrome (p=0.02). We found a negative relationship between the duration of COVID-19 symptoms and the quality of life (p<0.001). Moreover, our results showed that depressive symptoms were more common among females after the post-COVID-19 syndrome (p=0.01). Also, the quality of life was lower among females than males (p=0.004 for EQ-5D-3L index value, and p=0.007 for EQ-5D-3L VAS).

Conclusions

Our results suggest that post-COVID-19 syndrome causes a tremendous impact on the patients' quality of life and mental health. In addition, we found that the groups most psychologically affected were patients with post-COVID-19 dysautonomia, females, and patients with a longer duration of symptoms. Policy makers should assign priority rights to vulnerable groups in future psychiatric planning. Policy measures should focus on the mental health of post-COVID-19 patients who seem to be particularly vulnerable.

Atrial electromechanical delay in post-COVID-19 postural orthostatic tachycardia: Innocent bystander or pathologic factor

BACKGROUND

Post-COVID-19 syndrome represents a wide range of ongoing symptoms that persist beyond weeks or even months, after recovery from the acute phase. Postural orthostatic tachycardia (POT) is one of these symptoms with a poorly recognized underlying pathophysiology.

PURPOSE

We aimed to investigate atrial electromechanical delay (AEMD), demonstrated by electrocardiographic P wave dispersion (PWD) and tissue Doppler echocardiography (TDE) in patients with POST-COVID-19 POT (PCPOT).

METHODS

94 post-COVID-19 patients were enrolled and classified into two groups; PCPOT group, 34 (36.1%) patients, and normal heart rate (NR group), 60 (63.9%) patients. 31.9% of them were males and 68.1% were females, with a mean age of 35 ± 9 years. Both groups were compared in terms of PWD and AEMD.

RESULTS

As compared to the NR group, the PCPOT group showed a significant increase in PWD (49 ± 6 versus 25.6 ± 7.8, p < 0.001), higher CRP (37 ± 9 versus 30 ± 6, p = 0.04), prolonged left-atrial EMD, right-atrial EMD and inter-atrial EMD at (p = 0.006, 0.001, 0.002 respectively). Multivariate logistic regression analysis revealed that P wave dispersion (β 0.505, CI (0.224-1.138), p = 0.023), PA lateral (β 0.357, CI (0.214-0.697), p = 0.005), PA septal (β 0.651, CI. (0.325-0.861), p = 0.021), and intra-left atrial EMD (β 0.535, CI (0.353-1.346) p < 0.012) were independent predictors of PCPOT.

CONCLUSION

Atrial heterogenicity in the form of prolonged AEMD and PWD seems to be a reasonable underlying pathophysiology of PCPOT. This could provide a new concern during the management and novel pharmacological approaches in these patients.

Postural Orthostatic Tachycardia Syndrome After COVID-19: A Systematic Review of Therapeutic Interventions

ABSTRACT

Postural orthostatic tachycardia syndrome (POTS) is a clinical syndrome of inappropriate increase in heart rate on standing that has been recently also associated with Coronavirus Disease 2019 (COVID-19) as part of the postacute sequelae of COVID-19 (PASC) or long-COVID. We herein aimed to systematically review reported cases of POTS after COVID-19 and determine the characteristics of the subjects, the diagnostic approach used, and the treatment strategies. We searched the literature according to the following criteria: (1) diagnosis of POTS according to standard definition; (2) timely association with a probable or definite diagnosis of COVID-19; and (3) a description of the individual subject(s). We identified 21 reports meeting criteria between March 2020 and September 2022, including 68 subjects (51 females and 17 males, 3:1 ratio) with a mean age of 34 ± 12 years, with reports deriving from the United States, Norway, Sweden, Israel, Ireland, United Kingdom, Singapore, and Japan. Most cases had mild COVID-19 symptoms. The most common POTS symptoms were palpitations, chest pain, lightheadedness, and debilitating fatigue. The diagnosis was established by means of head-up tilt table or active stand test. Nonpharmacologic treatments (fluids, sodium intake, and compression stockings) were virtually always used, but largely ineffective. Subjects received different treatments, the most common being beta-adrenergic blockers (ie, propranolol), mineral corticosteroids (ie, fludrocortisone), midodrine, and ivabradine. Symptoms tended to improve over time, but most patients remained symptomatic for several months. In conclusion, POTS after COVID-19 is a clinical condition affecting young individuals, and disproportionately young women, occurring as part of PASC-long-COVID, often debilitating, which can be easily diagnosed with a thorough clinical assessment and measuring changes in orthostatic heart rate and blood pressure. POTS after COVID-19 seems to be poorly responsive to nonpharmacological treatments but with symptoms improving with pharmacological interventions. Given the limited data available, additional research is urgently needed with respect to its epidemiology, pathophysiology, and treatments.

High incidence of autonomic dysfunction and postural orthostatic tachycardia syndrome in patients with long-COVID: Implications for management and healthcare planning

BACKGROUND

Autonomic dysfunction including postural orthostatic tachycardia syndrome (POTS) has been reported in individuals with post-acute sequelae of Covid-19 (PASC). However, the degree of dysautonomia in PASC has not been compared to those with POTS and healthy controls.

METHODS

All participants were prospectively enrolled between 5^th August 2021 and 31^st October 2022. Autonomic testing included beat-to-beat hemodynamic monitoring to assess respiratory sinus arrhythmia, Valsalva ratio and orthostatic changes during a 10-minute active standing test as well as Sudomotor assessment. The Composite Autonomic Symptom Score (COMPASS-31) was used to assess symptoms and the Euroquol 5-Dimension survey (EQ-5D-5L) was used to assess health-related quality of life (HrQoL) measures.

RESULTS

A total of 99 participants (n=33 PASC, n=33 POTS and n=33 healthy controls; median age 32 [18], 85.9% females) were included. Compared to healthy controls, the PASC and POTS cohorts demonstrated significantly reduced respiratory sinus arrhythmia (p<0.001), greater heart rate increase during 10-minute active standing test (p<0.001), greater burden of autonomic dysfunction evidenced by higher COMPASS-31 scores across all subdomains (all p<0.001) and poor HrQoL across all EQ-5D-5L domains (all p<0.001), lower median EQ-VAS (p<0.001) and lower utility scores (p<0.001). The majority (79%) of those with PASC met the internationally established criteria for POTS.

CONCLUSION

The prevalence of autonomic symptomology or POTS was high in those with PASC, leading to poor HrQoL and high health disutility. Autonomic testing should be routinely undertaken in those with PASC to aid diagnosis and direct appropriate management to improve health outcomes.

TRIAL REGISTRATION

ANZCTR 12621000476831.

The relevance of pacing strategies in managing symptoms of post-COVID-19 syndrome

BACKGROUND

Post-COVID-19 syndrome (PCS) shares many features with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). PCS represents a major health issue worldwide because it severely impacts patients' work activities and their quality of life. In the absence of treatment for both conditions and given the beneficial effect of pacing strategies in ME/CFS, we conducted this study to assess the effectiveness of pacing in PCS patients.

METHODS

We retrospectively included patients meeting the World Health Organization definition of PCS who attended the Internal Medicine Department of Angers University Hospital, France between June 2020 and June 2022, and were followed up until December 2022. Pacing strategies were systematically proposed for all patients. Their medical records were reviewed and data related to baseline and follow-up assessments were collected. This included epidemiological characteristics, COVID-19 symptoms and associated conditions, fatigue features, perceived health status, employment activity, and the degree of pacing adherence assessed by the engagement in pacing subscale (EPS). Recovery was defined as the ability to return to work, and improvement was regarded as the reduction of the number and severity of symptoms.

RESULTS

A total of 86 patients were included and followed-up for a median time of 10 [6-13] months. Recovery and improvement rates were 33.7% and 23.3%, respectively. The EPS score was the only variable significantly associated with recovery on multivariate analysis (OR 40.43 [95% CI 6.22-262.6], p < 0.001). Patients who better adhered to pacing (high EPS scores) experienced significantly higher recovery and improvement rates (60-33.3% respectively) than those with low (5.5-5.5% respectively), or moderate (4.3-17.4% respectively) scores.

CONCLUSION

Our findings demonstrated that pacing is effective in the management of patients with PCS, and that high levels of adherence to pacing are associated with better outcomes.

Post -acute sequalae of COVID-19 and cardiac outcomes in U. S. military members

Post -acute sequalae of COVID-19 (PASC) among U.S. military members remains unexplored. A cohort study of U. S. military members who had a COVID-19 test result, with the specimen collected between March 1, 2020 and November 30, 2021 was conducted. Demographic, inpatient and outpatient data including cardiac event diagnoses were extracted from electronic medical records and compared COVID-19 test-positive and COVID-19 test-negative service members. We used univariate and multivariable logistic regression methods to determine the effect PASC on select cardiac events. Among 997,785 service members, 15,779 (1.6%) were diagnosed with a cardiac event. In fully adjusted models, PASC was significantly associated with increased odds of any cardiac event [OR =1.64 (95% CI: 1.57, 1.71]. PASC was associated with increased odds of myocarditis [OR = 5.86 (95% CI: 4.22, 8.15)], pericarditis [OR =3.08 (95% CI: 2.31, 4.11)], syncope [OR =1.52 (95% CI: 1.41, 1.63)], tachycardia [OR =1.72 (95% CI: 1.56, 1.89)], heart failure [OR =2.15 (95% CI: 1.76, 2.63)], bradycardia [OR =1.71 (95% CI: 1.50, 1.96)], and atrial fibrillation [OR =1.33(95% CI: 1.02, 1.74)] in fully adjusted models. In a sensitivity analysis of military members with no history of cardiac events, PASC was still significantly associated with increased odds of any cardiac event [OR =1.75 (95% CI: 1.67, 1.84)]. In conclusion, we observed a significant association between PASC and cardiac outcomes including; myocarditis, pericarditis, and heart failure. These associations were observed in a relatively young and healthy population and among those without pre-existing cardiac diagnoses.

Objective Hemodynamic Cardiovascular Autonomic Abnormalities in Post-Acute Sequelae of COVID-19

BACKGROUND

Many COVID-19 patients are left with symptoms several months after resolution of the acute illness; this syndrome is known as post-acute sequalae of COVID-19 (PASC). We aimed to determine the prevalence of objective hemodynamic cardiovascular autonomic abnormalities (CAA), explore sex differences, and assess the prevalence of CAA among hospitalized vs nonhospitalized patients with PASC.

METHODS

Patients with PASC (n = 70; female [F] = 56; 42 years of age; 95% confidence interval [CI], 40-48) completed standard autonomic tests, including an active stand test 399 days (338, 455) after their COVID-19 infection. Clinical autonomic abnormalities were evaluated.

RESULTS

Most patients with PASC met the criteria for at least 1 CAA (51; 73%; F = 43). The postural orthostatic tachycardia syndrome hemodynamic (POTSHR) criterion of a heart rate increase of > 30 beats per minute within 5 to 10 minutes of standing was seen in 21 patients (30%; F = 20; P = 0.037 [by sex]). The initial orthostatic hypotension hemodynamic (IOH40) criterion of a transient systolic blood pressure change of > 40 mm Hg in the first 15 seconds of standing was seen in 43 (61%) patients and equally among female and male patients (63% vs 57%; P = 0.7). Only 9 (13%) patients were hospitalized; hospitalized vs nonhospitalized patients had similar frequencies of abnormalities (67% vs 74%; P = 0.7).

CONCLUSIONS

Patients with PASC have evidence of CAA, most commonly IOH40, which will be missed unless an active stand test is used. Female patients have increased frequency of POTSHR, but IOH40 is equally prevalent between sexes. Finally, even nonhospitalized "mild" infections can result in long-term CAAs.

Post-COVID-19 Syndrome Mechanisms, Prevention and Management

As the population of patients recovering from COVID-19 grows, post COVID-19 challenges are recognizing by ongoing evidences at once. Long COVID is defined as a syndrome with a range of persistent symptoms that remain long after (beyond 12 weeks) the acute SARS-CoV-2 infection. Studies have shown that long COVID can cause multi-organ damages with a wide spectrum of manifestations. Many systems, but not limited to, including respiratory, cardiovascular, nervous, gastrointestinal, and musculoskeletal systems, are involved in long COVID. Fatigue and dyspnea are the most common symptoms of long COVID. Long COVID-19 may be driven by tissue damage caused by virus-specific pathophysiologic changes or secondary to pathological long-lasting inflammatory response because of viral persistence, immune dysregulation, and autoimmune reactions. Some risk factors like sex and age, more than five early symptoms, and specific biomarkers have been revealed as a probable long COVID predicator discussed in this review. It seems that vaccination is the only way for prevention of long COVID and it can also help patients who had already long COVID. Managing long COVID survivors recommended being in a multidisciplinary approach, and a framework for identifying those at high risk for post-acute COVID-19 must be proposed. Possible therapeutic options and useful investigation tools for follow-up are suggested in this review. In sum, as evidence and researches are regularly updated, we provide the current understanding of the epidemiology, clinical manifestation, suspected pathophysiology, associated risk factors, and treatment options of long COVID in this review.

Cardiopulmonary Phenotypes of Post Acute Sequelae of Severe Acute Respiratory Syndrome Coronavirus 2: A Narrative Review

The acute effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are well known; however, the long-term cardiopulmonary effects are less well characterized. The phenotypic expression of acute infection is heterogeneous, ranging from a complete absence of symptoms to shock, multisystem organ failure, and death. Patients with severe or critical coronavirus disease (COVID-19) who survive their initial illness can require a prolonged period of recovery lasting weeks to months. This specific patient group is part of a larger and even more heterogeneous group of patients who initially experience mild-to-moderate symptoms that fail to resolve over time. Collectively, patients recovering from severe or critical COVID-19 and those who continue to experience symptoms following a lower acuity infection are considered to have Post Acute Sequalae of SARS-CoV-2 infection (PASC). Using prognostic factors like myocardial infarction, myocarditis, pulmonary embolism, acute respiratory distress syndrome, need for mechanical ventilation or extracorporeal membrane oxygenation, and advanced pharmaceutical therapies that primarily occur or are instituted in the acute phase of illness one can begin to develop a taxonomy or corpus of PASC in its varied forms.

Long COVID and risk of erectile dysfunction in recovered patients from mild to moderate COVID-19

Patients with coronavirus disease 2019 (COVID-19) were shown to have reduced serum testosterone levels compared to healthy individuals. Low testosterone levels are linked with the development of erectile dysfunction (ED). In this case-controlled study, 20 healthy controls and 39 patients with ED 3 months after recovering from mild-to-moderate COVID-19 pneumonia were studied. The patients ranged in age from 31 to 47 years. To identify early and late COVID-19 infections, real-time polymerase-chain reaction (RT-PCR) and COVID-19 antibody testing were done. The levels of luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone (TT), free testosterone (FT), free androgenic index (FAI), and sex hormone-binding globulin (SHBG) were measured. The sexual health inventory for patients (SHIM) score was used to measure the erectile function of the patients and controls. When compared to the controls, the TT serum level in long COVID-19 (LC) patients with ED was low (p = 0.01). In contrast to controls, FT and FAI were both lower in LC patients with ED. (p = 0.001). FSH serum levels did not significantly differ (p = 0.07), but in ED patients, LH serum levels were elevated. SHIM scores were associated with low TT (p = 0.30), FT (p = 0.09), and high LH (p = 0.76) in LC patients with ED. Male patients with decreased serum levels of LH and testosterone may have hypothalamic-pituitary-gonadal axis dysfunction, which could lead to the development of LC-induced ED. Therefore, an in-depth research is necessary to confirm the causal link between COVID-19 and ED in LC patients.

Occurrence of comorbid diseases in patients after COVID-19

The COVID-19 pandemic has highlighted the potential impact of this disease on cardiovascular morbidity and mortality. Patients with established cardiovascular (CV) disease are at increased risk of severe infection and hospital-acquired adverse outcomes. This study aimed to investigate the prevalence and characteristics of comorbidities in COVID-19 patients. We analyzed data from 220 patients who previously contracted COVID-19. Statistical analysis was performed using SPSS software. The average age of the patients was 54.6 ± 11.4 years, and arterial hypertension (AH) was the most common comorbidity, affecting 55% of patients. Obesity was observed in one-third of patients, while coronary heart disease (CHD) and coronary heart failure (CHF) were reported in 17.7% and 11.8% of patients, respectively. Chronic kidney disease (CKD), atrial fibrillation (AF), and obstructive pulmonary disease (COPD) were less common. Cardiovascular diseases, particularly AH, were the most frequent comorbidities in COVID-19 patients. Understanding the prevalence and characteristics of comorbidities in COVID-19 patients is crucial for developing appropriate management strategies and improving clinical outcomes. Our findings highlight the importance of identifying and managing comorbidities in COVID-19 patients to reduce the risk of severe COVID-19 and improve clinical outcomes.

Potential of Nano-Antioxidants and Nanomedicine for Recovery from Neurological Disorders Linked to Long COVID Syndrome

Long-term neurological complications, persisting in patients who cannot fully recover several months after severe SARS-CoV-2 coronavirus infection, are referred to as neurological sequelae of the long COVID syndrome. Among the numerous clinical post-acute COVID-19 symptoms, neurological and psychiatric manifestations comprise prolonged fatigue, "brain fog", memory deficits, headache, ageusia, anosmia, myalgias, cognitive impairments, anxiety, and depression lasting several months. Considering that neurons are highly vulnerable to inflammatory and oxidative stress damages following the overproduction of reactive oxygen species (ROS), neuroinflammation and oxidative stress have been suggested to dominate the pathophysiological mechanisms of the long COVID syndrome. It is emphasized that mitochondrial dysfunction and oxidative stress damages are crucial for the pathogenesis of neurodegenerative disorders. Importantly, antioxidant therapies have the potential to slow down and prevent disease progression. However, many antioxidant compounds display low bioavailability, instability, and transport to targeted tissues, limiting their clinical applications. Various nanocarrier types, e.g., liposomes, cubosomes, solid lipid nanoparticles, micelles, dendrimers, carbon-based nanostructures, nanoceria, and other inorganic nanoparticles, can be employed to enhance antioxidant bioavailability. Here, we highlight the potential of phytochemical antioxidants and other neuroprotective agents (curcumin, quercetin, vitamins C, E and D, melatonin, rosmarinic acid, N-acetylcysteine, and Ginkgo Biloba derivatives) in therapeutic strategies for neuroregeneration. A particular focus is given to the beneficial role of nanoparticle-mediated drug-delivery systems in addressing the challenges of antioxidants for managing and preventing neurological disorders as factors of long COVID sequelae.

"Long Haulers"

Post-COVID conditions continue to afflict patients long after acute severe acute respiratory syndrome-coronavirus-2 (SARS CoV-2) infection. Over 50 symptoms across multiple organ systems have been reported, with pulmonary, cardiovascular, and neuropsychiatric sequelae occurring most frequently. Multiple terms have been used to describe post-COVID conditions including long COVID, long-haul COVID, postacute coronavirus disease 2019 (COVID-19), postacute sequelae of SARS-CoV-2 infection, long-term effects of COVID, and chronic COVID-19; however, standardized assessments and treatment algorithms for patients have generally been lacking. This review discusses the epidemiology and risk factors for post-COVID conditions and provides a general overview of the diagnostic assessment and treatment of specific manifestations. Data derived from the multitude of observational studies and scientific investigations into pathogenesis are providing a clearer understanding of the distinct phenotypes of post-COVID conditions. Insight gained from these studies and ongoing interventional trials continues to lead to the development of clinical protocols directed toward improving COVID-19 survivors' quality of life and preventing or reducing long-term morbidity.

Postural Orthostatic Tachycardia Syndrome in COVID-19: A Contemporary Review of Mechanisms, Clinical Course and Management

The long-term implications of COVID-19 have garnered increasing interest in recent months, with Long-COVID impacting over 65 million individuals worldwide. Postural orthostatic tachycardia syndrome (POTS) has emerged as an important component of the Long-COVID umbrella, estimated to affect between 2 and 14% of survivors. POTS remains very challenging to diagnose and manage - this review aims to provide a brief overview of POTS as a whole and goes on to summarize the available literature pertaining to POTS in the setting of COVID-19. We provide a review of available clinical reports, outline proposed pathophysiological mechanisms and end with a brief note on management considerations.

Long COVID: mechanisms, risk factors and recovery

NEW FINDINGS

What is the topic of this review? The emerging condition of long COVID, its epidemiology, pathophysiological impacts on patients of different backgrounds, physiological mechanisms emerging as explanations of the condition, and treatment strategies being trialled. The review leads from a Physiological Society online conference on this topic. What advances does it highlight? Progress in understanding the pathophysiology and cellular mechanisms underlying Long COVID and potential therapeutic and management strategies.

ABSTRACT

Long COVID, the prolonged illness and fatigue suffered by a small proportion of those infected with SARS-CoV-2, is placing an increasing burden on individuals and society. A Physiological Society virtual meeting in February 2022 brought clinicians and researchers together to discuss the current understanding of long COVID mechanisms, risk factors and recovery. This review highlights the themes arising from that meeting. It considers the nature of long COVID, exploring its links with other post-viral illnesses such as myalgic encephalomyelitis/chronic fatigue syndrome, and highlights how long COVID research can help us better support those suffering from all post-viral syndromes. Long COVID research started particularly swiftly in populations routinely monitoring their physical performance - namely the military and elite athletes. The review highlights how the high degree of diagnosis, intervention and monitoring of success in these active populations can suggest management strategies for the wider population. We then consider how a key component of performance monitoring in active populations, cardiopulmonary exercise training, has revealed long COVID-related changes in physiology - including alterations in peripheral muscle function, ventilatory inefficiency and autonomic dysfunction. The nature and impact of dysautonomia are further discussed in relation to postural orthostatic tachycardia syndrome, fatigue and treatment strategies that aim to combat sympathetic overactivation by stimulating the vagus nerve. We then interrogate the mechanisms that underlie long COVID symptoms, with a focus on impaired oxygen delivery due to micro-clotting and disruption of cellular energy metabolism, before considering treatment strategies that indirectly or directly tackle these mechanisms. These include remote inspiratory muscle training and integrated care pathways that combine rehabilitation and drug interventions with research into long COVID healthcare access across different populations. Overall, this review showcases how physiological research reveals the changes that occur in long COVID and how different therapeutic strategies are being developed and tested to combat this condition.

Malmö POTS symptom score: Assessing symptom burden in postural orthostatic tachycardia syndrome

BACKGROUND

Postural orthostatic tachycardia syndrome (POTS) is a common cardiovascular autonomic disorder characterized by excessive heart rate (HR) increase on standing and symptoms of orthostatic intolerance, posing significant limitations on functional capacity. No objective tool exists to classify symptom burden in POTS.

METHODS

We conducted a case-control study in 62 POTS patients and 50 healthy controls to compare symptom burden between groups using the newly developed, self-rating, 12-item, Malmö POTS Score (MAPS; 0-10 per item, total range 0-120) based on patients own perception of symptoms through visual analogue scale assessment. We have also explored correlations between symptom severity assessed by MAPS, basic clinical parameters and postural haemodynamic changes.

RESULTS

POTS patients showed significantly higher total MAPS score (78 ± 20 vs. 14 ± 12, p < 0.001), higher baseline systolic blood pressure (BP), diastolic BP and HR (p < 0.001) compared with healthy controls. The most prominent symptoms in POTS were palpitations, fatigue and concentration difficulties. Haemodynamic parameters on standing were significantly correlated with palpitations in POTS after adjustment for age and sex (lower systolic and diastolic BP, and higher HR) (p < 0.001 for all). Orthostatic HR was significantly associated with concentration difficulties and total MAPS score. The optimal cut-point value of MAPS to differentiate POTS and healthy controls was ≥42 (sensitivity, 97%; specificity, 98%).

CONCLUSIONS

Symptom severity, as assessed by MAPS score, is fivefold higher in POTS compared with healthy individuals. The new MAPS score can be useful as a semiquantitative system to assess symptom burden, monitor disease progression and evaluate pre-test likelihood of disease.

Most Common Long COVID Physical Symptoms in Working Age Adults Who Experienced Mild COVID-19 Infection: A Scoping Review

BACKGROUND

One-third of patients who recover from COVID-19 present with long COVID. Their symptoms are broad, affecting their physical functioning and, ultimately, their quality of life. Many of those individuals who develop long COVID, possibly from a mild COVID-19 infection, are in the 18-65 age group. This prolongation of malaise directly influences national workforce economies.

OBJECTIVES

To summarise the commonly reported physical symptoms of long COVID in order to inform potential adjustments in healthcare for the employable population.

METHODS

The Embase, CINAHL, Medline, SCOPUS, and WHO COVID-19 databases were searched. The study selection process was based on the PRISMA guidelines. The extracted data were synthesised and presented narratively.

RESULTS

7403 studies were accessed, comprising 60 cohort studies and 10 case series/studies, representing 289,213 patients who met our criteria. The most frequently reported physical symptoms were fatigue (92%), shortness of breath (SOB) (81.8%), muscle pain (43.6%), and joint pain (34.5%).

CONCLUSIONS

The range of reported physical symptoms was broad and varied; the main ones being fatigue, breathlessness/SOB, and pain. Similarities observed between long COVID and other post-acute infection syndromes may help formulate protocols to manage and promote recovery for long COVID patients. Inconsistencies were evident, particularly with a lack of adherence to the standardised definitions of long COVID.

Apparent Risks of Postural Orthostatic Tachycardia Syndrome Diagnoses After COVID-19 Vaccination and SARS-Cov-2 Infection

Postural orthostatic tachycardia syndrome (POTS) has been previously described after SARS-CoV-2 infection; however, limited data is available on the relation of POTS with COVID-19 vaccination. Here we show in a cohort of 284,592 COVID-19 vaccinated individuals using a sequence-symmetry analysis, that the odds of POTS are higher 90 days after vaccine exposure than 90 days prior to exposure, and that the odds for POTS are higher than referent conventional primary care diagnoses, but lower than the odds of new POTS diagnosis after SARS-CoV-2 infection. Our results identify a possible association between COVID-19 vaccination and incidence of POTS. Notwithstanding the probable low incidence of POTS after COVID-19 vaccination, particularly when compared to SARS-Cov-2 post-infection odds which were five times higher, our results suggest that further studies, are needed to investigate the incidence and etiology of POTS occurring after COVID-19 vaccination.

Plasma proteomic profiling in postural orthostatic tachycardia syndrome (POTS) reveals new disease pathways

Postural orthostatic tachycardia syndrome (POTS) is a cardiovascular autonomic disorder characterized by excessive heart rate increase on standing, leading to debilitating symptoms with limited therapeutic possibilities. Proteomics is a large-scale study of proteins that enables a systematic unbiased view on disease and health, allowing stratification of patients based on their protein background. The aim of the present study was to determine plasma protein biomarkers of POTS and to reveal proteomic pathways differentially regulated in POTS. We performed an age- and sex-matched, case-control study in 130 individuals (case-control ratio 1:1) including POTS and healthy controls. Mean age in POTS was 30 ± 9.8 years (84.6% women) versus controls 31 ± 9.8 years (80.0% women). We analyzed plasma proteins using data-independent acquisition (DIA) mass spectrometry. Pathway analysis of significantly differently expressed proteins was executed using a cutoff log2 fold change set to 1.2 and false discovery rate (p-value) of < 0.05. A total of 393 differential plasma proteins were identified. Label-free quantification of DIA-data identified 30 differentially expressed proteins in POTS compared with healthy controls. Pathway analysis identified the strongest network interactions particularly for proteins involved in thrombogenicity and enhanced platelet activity, but also inflammation, cardiac contractility and hypertrophy, and increased adrenergic activity. Our observations generated by the first use a label-free unbiased quantification reveal the proteomic footprint of POTS in terms of a hypercoagulable state, proinflammatory state, enhanced cardiac contractility and hypertrophy, skeletal muscle expression, and adrenergic activity. These findings support the hypothesis that POTS may be an autoimmune, inflammatory and hyperadrenergic disorder.