Early Prediction of Disease Progression in Patients with Severe COVID-19 Using C-Reactive Protein to Albumin Ratio.

BACKGROUND: Early identification of patients with severe coronavirus disease (COVID-19) at an increased risk of progression may promote more individualized treatment schemes and optimize the use of medical resources. This study is aimed at investigating the utility of the C-reactive protein to albumin (CRP/Alb) ratio for early risk stratification of patients. METHODS: We retrospectively reviewed 557 patients with COVID-19 with confirmed outcomes (discharged or deceased) admitted to the West Court of Union Hospital, Wuhan, China, between January 29, 2020 and April 8, 2020. Patients with severe COVID-19 (n = 465) were divided into stable (n = 409) and progressive (n = 56) groups according to whether they progressed to critical illness or death during hospitalization. To predict disease progression, the CRP/Alb ratio was evaluated on admission. RESULTS: The levels of new biomarkers, including neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, CRP/Alb ratio, and systemic immune-inflammation index, were higher in patients with progressive disease than in those with stable disease. Correlation analysis showed that the CRP/Alb ratio had the strongest positive correlation with the sequential organ failure assessment score and length of hospital stay in survivors. Multivariate logistic regression analysis showed that percutaneous oxygen saturation (SpO2), D-dimer levels, and the CRP/Alb ratio were risk factors for disease progression. To predict clinical progression, the areas under the receiver operating characteristic curves of Alb, CRP, CRP/Alb ratio, SpO2, and D-dimer were 0.769, 0.838, 0.866, 0.107, and 0.748, respectively. Moreover, patients with a high CRP/Alb ratio (≥1.843) had a markedly higher rate of clinical deterioration (log - rank p < 0.001). A higher CRP/Alb ratio (≥1.843) was also closely associated with higher rates of hospital mortality, ICU admission, invasive mechanical ventilation, and a longer hospital stay. CONCLUSION: The CRP/Alb ratio can predict the risk of progression to critical disease or death early, providing a promising prognostic biomarker for risk stratification and clinical management of patients with severe COVID-19.

CardiOvaScular Mechanisms In Covid-19: methodology of a prospective observational multimodality imaging study (COSMIC-19 study).

BACKGROUND: 8-28% of patients infected with COVID-19 have evidence of cardiac injury, and this is associated with an adverse prognosis. The cardiovascular mechanisms of injury are poorly understood and speculative. We aim to use multimodality cardiac imaging including cardiac magnetic resonance (CMR) imaging, computed tomography coronary angiography (CTCA) and positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (18F-FDG-PET/CT) to identify the cardiac pathophysiological mechanisms related to COVID-19 infections. METHODS: This is a single-centre exploratory observational study aiming to recruit 50 patients with COVID-19 infection who will undergo cardiac biomarker sampling. Of these, 30 patients will undergo combined CTCA and 18F-FDG-PET/CT, followed by CMR. Prevalence of obstructive and non-obstructive atherosclerotic coronary disease will be assessed using CTCA. CMR will be used to identify and characterise myocardial disease including presence of cardiac dysfunction, myocardial fibrosis, myocardial oedema and myocardial infarction. 18F-FDG-PET/CT will identify vascular and cardiac inflammation. Primary endpoint will be the presence of cardiovascular pathology and the association with troponin levels. DISCUSSION: The results of the study will identify the presence and modality of cardiac injury associated COVID-19 infection, and the utility of multi-modality imaging in diagnosing such injury. This will further inform clinical decision making during the pandemic. TRIAL REGISTRATION: This study has been retrospectively registered at the ISRCTN registry (ID ISRCTN12154994) on 14th August 2020. Accessible at https://www.isrctn.com/ISRCTN12154994.

[Effect of anticoagulant therapy on the course of COVID-19 in comorbid patients].

INTRODUCTION: Analysis of the pathogenesis of coronavirus infection caused SARS-CoV-2 indicates a significant impact of hemorheological disorders on its course and outcomes. It is known that chronic cardiovascular diseases are associated with the risk of severe course and lethal outcomes both in COVID-19 and other infectious diseases. Therefore, in each case it is necessary to study the interaction and mutual influence of different components of the treatment program prescribed to such patients.The purpose of this work was to evaluate the effect of coagulation activity on the course of a novel coronavirus infection (COVID-19) and to justify the management of comorbid patients having been received novel oral anticoagulants (NOACs) in previously selected doses according to indications in concomitant somatic diseases. MATERIAL AND METHODS: Total 76 cases of confirmed coronavirus infection in patients who had been received initial therapy on an outpatient basis were analyzed. 26 patients who received NOACs (rivaroxaban, apixaban, dabigatran) made up the main group and 50 - the comparison (control) group in which patients had not been administered any drugs that affect blood clotting until the episode of COVID-19. All patients have been prescribed therapy following the Provisional guidelines «Prevention, diagnosis and treatment of coronavirus infection (COVID-19)¼ (https://static-0.minzdrav.gov.ru/system/attachments/attaches/). RESULTS AND DISCUSSION: The number of hospitalizations was significantly fewer in the group of patients who had been received NOACs (19 vs. 66% in the control group). No deaths or cases of severe respiratory and/or renal failure were observed in the main group, while adverse outcomes were noted in 14% of patients who had not been administered these drugs. CONCLUSION: Taking NOACs reduces the probability of severe course and adverse outcomes in the development of coronavirus infection caused by SARS-CoV-2, which indicates a significant contribution of coagulation mechanisms to the pathogenesis in COVID-19. There were no indications for drug replacement and correction of anticoagulant therapy regimens in patients who received adequate therapy with oral anticoagulants for treating a non-severe form of coronavirus infection in ambulatory patient settings.

Effects of Life Events and Social Isolation on Stroke and Coronary Heart Disease.

The current coronavirus disease 2019 (COVID-19) pandemic represents a severe, life-changing event for people across the world. Life changes may involve job loss, income reduction due to furlough, death of a beloved one, or social stress due to life habit changes. Many people suffer from social isolation due to lockdown or physical distancing, especially those living alone and without family. This article reviews the association of life events and social isolation with cardiovascular disease, assembling the current state of knowledge for stroke and coronary heart disease. Possible mechanisms underlying the links between life events, social isolation, and cardiovascular disease are outlined. Furthermore, groups with increased vulnerability for cardiovascular disease following life events and social isolation are identified, and clinical implications of results are presented.

Onset of Coronary Heart Disease is Associated with HCMV Infection and Increased CD14 +CD16 + Monocytes in a Population of Weifang, China.

OBJECTIVE: To investigate the relationship between human cytomegalovirus (HCMV) infection and peripheral blood CD14 +CD16 + monocytes in the pathogenesis of coronary heart disease (CHD), and to elucidate the mechanism of pathogenesis in CHD by analyzing the correlation between infection, inflammation, and CHD, to provide a basis for the prevention, evaluation, and treatment of the disease. METHODS: In total, 192 patients with CHD were divided into three groups: latent CHD, angina pectoris, and myocardial infarction. HCMV-IgM and -IgG antibodies were assessed using ELISA; CD14 +CD16 + monocytes were counted using a five-type automated hematology analyzer; mononuclear cells were assessed using fluorescence-activated cell sorting; and an automatic biochemical analyzer was used to measure the levels of triglyceride, cholesterol, high- and low-density lipoprotein cholesterols, lipoprotein, hs-CRp and Hcy. RESULTS: The positive rates of HCMV-IgM and -IgG were significantly higher in the CHD groups than in the control group. HCMV infection affects lipid metabolism to promote immune and inflammatory responses. CONCLUSION: HCMV infection has a specific correlation with the occurrence and development of CHD. The expression of CD14 +CD16 + mononuclear cells in the CHD group was increased accordingly and correlated with acute HCMV infection. Thus, HCMV antibody as well as peripheral blood CD14 +CD16 + mononuclear cells can be used to monitor the occurrence and development of CHD.

Sympathetic activation: a potential link between comorbidities and COVID-19.

In coronavirus disease 2019 (COVID-19), higher morbidity and mortality are associated with age, male gender, and comorbidities, such as chronic lung diseases, cardiovascular pathologies, hypertension, kidney diseases, diabetes mellitus, and obesity. All of the above conditions are characterized by increased sympathetic discharge, which may exert significant detrimental effects on COVID-19 patients, through actions on the lungs, heart, blood vessels, kidneys, metabolism, and/or immune system. Furthermore, COVID-19 may also increase sympathetic discharge, through changes in blood gases (chronic intermittent hypoxia, hyperpnea), angiotensin-converting enzyme (ACE)1/ACE2 imbalance, immune/inflammatory factors, or emotional distress. Nevertheless, the potential role of the sympathetic nervous system has not yet been considered in the pathophysiology of COVID-19. In our opinion, sympathetic overactivation could represent a so-far undervalued mechanism for a vicious circle between COVID-19 and comorbidities.

Cardiac injuries in coronavirus disease 2019 (COVID-19).

As the coronavirus disease 2019 (COVID-19) epidemic worsens, this global pandemic is impacting more than 200 countries/regions and more than 4,500,000 confirmed cases worldwide. COVID-19 is caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), which might attack not only the respiratory system, but also the other important organs, including the heart. It was reported that COVID-19 patients with a past history of cardiovascular diseases would have a higher mortality. Meanwhile, elevated troponin levels were frequently observed in COVID-19 cases. Besides the comprehensive treatments for COVID-19, as a cardiologist, we should also remain vigilant about the cardiac injuries, especially those with severe emergent cardiovascular symptoms.

Clinical features of patients with coronavirus disease 2019 from a designated hospital in Beijing, China.

Clinical and laboratory data on patients with coronavirus disease 2019 (COVID-19) in Beijing, China, remain extremely limited. In this study, we summarized the clinical characteristics of patients with COVID-19 from a designated hospital in Beijing. In total, 55 patients with laboratory-confirmed SARS-CoV-2 infection in Beijing 302 Hospital were enrolled in this study. Demographic data, symptoms, comorbidities, laboratory values, treatments, and clinical outcomes were all collected and retrospectively analyzed. A total of 15 (27.3%) patients had severe symptoms, the mean age was 44.0 years (interquartile range [IQR], 34.0-56.0), and the median incubation period was 7.5 days (IQR, 5.0-11.8). A total of 26 (47.3%) patients had exposure history in Wuhan of less than 2 weeks, whereas 20 (36.4%) patients were associated with familial clusters. Also, eighteen (32.7%) patients had underlying comorbidities including hypertension. The most common symptom of illness was fever (45; 81.8%); 51 (92.7%) patients had abnormal findings on chest computed tomography. Laboratory findings showed that neutrophil count, percentage of lymphocyte, percentage of eosinophil, eosinophil count, erythrocyte sedimentation rate, albumin, and serum ferritin are potential risk factors for patients with a poor prognosis. A total of 26 patients (47.3%) were still hospitalized, whereas 29 (52.7%) patients had been discharged. Compared with patients in Wuhan, China, the symptoms of patients in Beijing are relatively mild. Older age, more comorbidities, and more abnormal prominent laboratory markers were associated with a severe condition. On the basis of antiviral drugs, it is observed that antibiotics treatment, appropriate dosage of corticosteroid, and gamma globulin therapy significantly improve patients' outcomes. Early identification and timely medical treatment are important to reduce the severity of patients with COVID-19.

[COVID-19 pandemia: Impact on the cariovascular system. Data of 1st April 2020]. / Pandémie COVID-19 : impact sur le systeme cardiovasculaire. Données disponibles au 1er avril 2020.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects host cells with angiotensin receptors, leading to pneumonia linked to COVID-19. The virus has a double impact on the cardiovascular system, the infection will be more intense if the host has cardiovascular co-morbidities and the virus can cause life-threatening cardiovascular lesions. Therapies associated with COVID-19 may have adverse cardiovascular effects. Therefore, special attention should be given to cardiovascular protection during COVID-19 infection.

Diminished impact of cytomegalovirus infection on graft vasculopathy development in the antiviral prophylaxis era - a retrospective study.

Evidence concerning an association between cytomegalovirus (CMV) infection and accelerated cardiac allograft vasculopathy (CAV) is inconclusive. Data were analyzed retrospectively from 297 consecutive heart transplants between 1.1.2002 and 31.12.2012. Patients ≤18 years of age, survival, and follow-up ≤1-year post-transplant and patients with early CAV were excluded. CMV-infection was diagnosed and monitored closely in the first year. CAV was diagnosed by coronary angiography via left heart catheterization, and results were categorized according to the International Society of Heart and Lung Transplantation (ISHLT) scoring system. Risk factors for CAV were tested in a multivariable model. Median follow-up was 7.5 years (IQR: 5.6-10.3). CMV infection in the first year after transplantation occurred in 26% of patients (n = 78), CMV disease in 5% (n = 15). CAV ≥1 ISHLT was detected in 36% (n = 108). Incidence of CAV >1 ISHLT and severity of CAV increased over time. No statistically significant association between CMV infection and disease within the first year and risk of CAV after 1-year post-HTx was detected in the univariate (P = 0.16) and multivariable [hazard ratio (HR), 1.36; confidence interval (CI), 0.89-2.07; P = 0.16] Cox regression. In the multivariable Cox regression, donor age (HR, 1.04; 95% CI, 1.02-1.06; P < 0.01) and acute cellular rejection (ACR) ≥2R in the first year after HTx (HR, 1.77; 95% CI, 1.06-2.95; P = 0.03) were independent risk factors for CAV development. In our cohort, CMV infection and disease in the first year after transplantation did not significantly influence the risk of CAV in the long-term follow-up.

Circulating fibroblast activation protein activity and antigen levels correlate strongly when measured in liver disease and coronary heart disease.

BACKGROUND AND AIM: Circulating fibroblast activation protein (cFAP) is a constitutively active enzyme expressed by activated fibroblasts that has both dipeptidyl peptidase and endopeptidase activities. We aimed to assess the correlation between cFAP activity and antigen levels and to compare variations in levels. METHODS: In plasma of 465 control individuals, 368 patients with coronary heart disease (CHD) and 102 hepatitis C virus (HCV) infected patients with severe liver disease before and after liver transplant, cFAP activity levels were measured with a newly developed cFAP activity assay. In the same samples, cFAP antigen levels were measured using a commercially available cFAP ELISA. Correlation analyses between activity and antigen levels were performed by calculating Pearson's correlation coefficient (ρ). Additionally, normal ranges, determinants and differences between cohorts and between anticoagulants were investigated. RESULTS: cFAP activity and antigen levels significantly correlated in controls (ρ: 0.660, p<0.001) and in CHD patients (ρ: 0.709, p<0.001). cFAP activity and antigen levels in the HCV cohort were significantly lower in the samples taken after liver transplantation (p<0.001) and normalized toward levels of healthy individuals. Furthermore, cFAP activity and antigen levels were higher in men and significantly associated with body mass index. Also, cFAP activity and antigen levels were higher in EDTA plasma as compared to the levels in citrated plasma from the same healthy individuals. CONCLUSIONS: For analyzing cFAP levels, either activity levels or antigen levels can be measured to investigate differences between individuals. However, it is of importance that blood samples are collected in the same anticoagulant.

Viral metagenomics analysis of feces from coronary heart disease patients reveals the genetic diversity of the Microviridae.

Recent studies have declared that members of the ssDNA virus family Microviridae play an important role in multiple environments, as they have been found taking a dominant position in the human gut. The aim of this study was to analyze the overall composition of the gut virome in coronary heart disease (CHD) patients, and try to discover the potential link between the human gut virome and CHD. Viral metagenomics methods were performed to detect the viral sequences in fecal samples collected from CHD inpatients and healthy persons as controls. We present the analysis of the virome composition in these CHD patients and controls. Our data shows that the virome composition may be linked to daily living habits and the medical therapy of CHD. Virgaviridae and Microviridae were the two dominant types of viruses found in the enteric virome of CHD patients. Fourteen divergent viruses belonging to the family Microviridae were found, twelve of which were grouped into the subfamily Gokushovirinae, while the remaining two strains might represent two new subfamilies within Microviridae, according to the phylogenetic analysis. In addition, the genomic organization of these viruses has been characterized.

Pathophysiology and management of cardiovascular disease in patients with HIV.

Results from several studies have suggested that people with HIV have an increased risk of cardiovascular disease, especially coronary heart disease, compared with people not infected with HIV. People living with HIV have an increased prevalence of traditional cardiovascular disease risk factors, and HIV-specific mechanisms such as immune activation. Although older, more metabolically harmful antiretroviral regimens probably contributed to the risk of cardiovascular disease, new data suggest that early and continuous use of modern regimens, which might have fewer metabolic effects, minimises the risk of myocardial infarction by maintaining viral suppression and decreasing immune activation. Even with antiretroviral therapy, however, immune activation persists in people with HIV and could contribute to accelerated atherosclerosis, especially of coronary lesions that are susceptible to rupture. Therefore, treatments that safely reduce inflammation in people with HIV could provide additional cardiovascular protection alongside treatment of both traditional and non-traditional risk factors.

Impact of nucleoside reverse transcriptase inhibitors on coronary heart disease.

The nucleoside and nucleotide reverse transcriptase inhibitor (N[t]RTI) drug class remains an integral component of effective antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection. However, these drugs are associated with toxicities, through their off-target effects, that may significantly contribute to a number of long-term comorbidities, including coronary artery disease (CAD) and myocardial infarction (MI), recognized to occur with increased frequency in those with HIV undergoing treatment with ART. The contribution of N(t)RTI to CAD and MI may arise either indirectly through induction of metabolic toxicities such as dyslipidemia and insulin resistance, or directly through impact on pathologic pathways involved in development of MI, such as altered platelet responsiveness or endothelial dysfunction. This review focuses on the available data relating to use of individual N(t)RTI drugs and the drug class as a whole and CAD, with a focus on MI.

Impact of antiretroviral medications on fasting lipid parameters.

It is widely accepted that metabolic disease in human immunodeficiency virus (HIV) develops at the intersection of traditional risk factors and HIV-specific contributors, but in observational studies it is difficult to dissect the contribution of the two. This review describes the metabolic impact of antiretroviral medications recommended in the first-line treatment in HIV-infected naive patients. At a clinical level, coronary heart disease screening and management will continue to be of paramount importance in the long-term management of HIV-positive patients on antiretroviral therapy.

Epidemiology of coronary heart disease in patients with human immunodeficiency virus.

As a growing number of patients infected with human immunodeficiency virus (HIV) have access to antiretroviral therapy and achieve virologic suppression, the focus of clinical care is shifting from treating the infectious complications of advanced immunodeficiency to managing and preventing chronic disease. The aging of the HIV-positive population and increased rates of chronic disease complications in the setting of HIV infection have increased the impact of noncommunicable diseases such as coronary heart disease (CHD). The effect of HIV on CHD is independent of traditional cardiovascular risk factors and antiretroviral medications and is likely due in part to the chronic inflammation and immune activation underlying HIV infection. This article describes the current state of epidemiologic knowledge on CHD in HIV infection. It highlights key studies in the field and summarizes epidemiologic data with respect to traditional and novel CHD risk factors, specialized clinical subgroups, and broader cardiovascular outcomes.

The relation between hepatitis C virus and coronary heart disease.

It is well known that chronic hepatitis C is associated with insulin resistance and metabolic syndrome which are risk factors for atherosclerosis and coronary heart disease. As a result, chronic hepatitis C might be thought, through its association with metabolic syndrome, to increase the risk of myocardial infarction. However, unexpectedly it was found that HCV infection is not associated with an increased risk of myocardial infarction. We are providing here an hypothesis of the mechanism through which HCV infection does not increase the risk for myocardial infarction and also may be protecting against some cardiovascular risks that typically develop in many patients with metabolic syndrome who do not have chronic hepatitis C. The suggested mechanism includes factors that are normal consequences of chronic hepatitis, such as: significant decrease in cholesterol and LDL levels; defected blood clotting system; impaired myocardial function; decreased venous return and central venous pressure; increased nitric oxide and TNF alpha levels; and diminished cardiac beta receptors signal transduction. All these factors contribute to a protective effect against cardiac ischemia and coronary heart disease. We suggest further studies to investigate this hypothesis.

Might infection explain the higher risk of coronary heart disease in South Asians? Systematic review comparing prevalence rates with white populations in developed countries.

OBJECTIVES: South Asians in developed countries such as the UK are at comparatively high risk of coronary heart disease for reasons which are not fully understood. One unexplored hypothesis is more infections in this ethnic group. This study assessed whether the prevalence of infections among South Asians differs from that among White populations of European origin in developed countries. STUDY DESIGN: Systematic review. METHODS: Medline, Web of Science and Google Scholar databases were searched. In addition, reference lists and citations were reviewed. RESULTS: Twenty-one studies reported prevalence rates and mean antibody levels of infection with 17 different pathogens or non-specific markers of infection. Among bacterial infections, higher rates of Escherichia coli and Mycobacterium tuberculosis infection were found in South Asians. No consistent differences were found for periodontal pathogens, Helicobacter pylori, Staphylococcus aureus, Chlamydia pneumoniae and Mycobacterium avium. For viral pathogens, higher rates of hepatitis A, hepatitis B and cytomegalovirus; and lower rates of herpes simplex, hepatitis C, human immunodeficiency virus and varicella zoster virus were found among South Asians. No difference was seen in the prevalence of hepatitis G virus in South Asians. Levels of non-specific markers of infection (total immunoglobulin G, endotoxin) were higher in South Asians. CONCLUSIONS: The number of studies was small. Differences in the prevalence of specific infections were found, but the current evidence is insufficient to support or reject the hypothesis under examination. Further studies are warranted.

Predicted coronary heart disease risk in croatian HIV infected patients treated with combination antiretroviral therapy.

We assessed the coronary heart disease (CHD) risk in 130 HIV-infected patients with no major past cardiovascular event treated with combination antiretroviral therapy (CART) between May 2004 and June 2005. We also investigated the association of HIV disease parameters (CD4 + T-cell counts, HIV viral load, AIDS diagnosis, antiretroviral medications and lipodystrophy), demographics, anthropometrics, clinical features, smoking status, dyslipidemia, adherence to the Mediterranean diet, and the metabolic syndrome (MS) to the Framingham risk score. The median 10-year CHD risk was 6.4% (IQR 3.3-13.0) for males and 1.8% (IQR 1.0-6.7) for females. The CHD risk was > or = 10% in 31.1% (32 of 103) males and in 14.8% (4 of 27) females. MS was present in 27 (20.8%) individuals. Participants who met the definition of the MS had a 2.63 times greater chance of having a CHD risk 210% (95% CI, 1.09-6.39; p = 0.032). On multivariable analysis, we found that a CHD risk > or = 10% was associated with: a lowest ever CD4+ T-cell counts of less than 50 per microliter and a past history of AIDS (OR, 6.26; 95% CI, 1.61-24.36; p = 0.008); alcohol consumption 210 g/day (OR, 3.87; 95% CI, 1.56-14.22; p = 0.041); and age 243 years (OR, 1.30; 95% CI, 1.17-1.45; p < 0.001). Interventions to reduce the modifiable cardiovascular risk are needed in Croatian patients treated with CART

High prevalence of intramural coronary infection in patients with drug-resistant cardiac syndrome X: comparison with chronic stable angina and normal controls.

BACKGROUND: Coronary microvascular dysfunction has been reported along with myocardial viral infection. Whether intramural coronary vessels infection plays a role in patients with cardiac syndrome X (CSX) is unknown. METHODS: Thirteen consecutive patients (four men, nine women, mean age 51±10.5 years) with drug-resistant CSX underwent left ventricular endomyocardial biopsy. Myocardial tissue was examined for histology, immunohistochemistry and for the presence of cardiotropic viruses by PCR analysis. In the presence of a viral infection on the whole tissue, laser microdissection was performed to analyse the viral genome selectively in intramural vessels and cardiomyocytes. Controls were surgical cardiac biopsies from patients with chronic stable angina and from patients with mitral stenosis and normal cardiac function (normal controls). RESULTS: Histology showed hypertrophy and degeneration of cardiomyocytes with interstitial and replacement fibrosis in all CSX, while focal lymphocytic myocarditis was additionally recognised in three patients. No vasculitis was observed. Viral genomes were detected in nine of 13 CSX (Epstein-Barr virus in four, adenovirus in three, human herpes virus (HHV) 6 in one, Epstein-Barr adenovirus co-infection in one). Laser microdissection showed that Epstein-Barr and adenovirus localised both in cardiomyocytes and intramural vessels, while HHV-6 infection was confined to the vessel wall. CONCLUSIONS: Viral genomes can be detected in intramural vessels of up to 69% of drug-resistant CSX. Coronary small vessels infection represents an alternative pathophysiological mechanism of this syndrome and can explain the poor response to anti-ischaemic drugs.