Characteristics and prognosis of myocardial infarction in patients with normal coronary arteries

Management of myocardial infarction with non-obstructive coronary arteries (MINOCA) in Germany: a single-center study on hospital resources and healthcare economics

Background

Patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) present as a main feature ≤50% stenosis upon angiography despite clinical symptoms and biomarker elevation related to acute coronary syndrome. Due to broad availability of high sensitivity troponin testing as well as invasive and non-invasive imaging, this clinical entity receives increasing clinical awareness.

Objective

We aimed to investigate the in-hospital work flow and economic impact of MINOCA vs. MICAD (myocardial infarction with obstructive coronary artery disease) patients and related clinical outcomes in a single-center patient collective of a large university heart center in Germany.

Methods

We retrospectively screened and analyzed all patients who were admitted to our hospital under the suspicion of an acute coronary syndrome within a 12-month period (2017-2018) for further diagnostics and treatment. All included patients showed a pathological troponin elevation and received invasive coronary angiography for acute coronary syndrome. Associated in-hospital costs, procedural and various clinical parameters as well as timelines and parameters of work-flow were obtained.

Results

After screening of 3,021 patients, we included 660 patients with acute coronary syndrome. Of those, 118 patients were attributed to the MINOCA-group. 542 patients presented with a "classical" myocardial infarction (MICAD group). MINOCA patients were less frail, more likely female, but showed no relevant difference in age or other selected comorbidities except for fewer cases of diabetes. In-hospital mortality (11% vs. 0%; p < 0.001) and 30-day mortality (17.3% vs. 4.2%; p < 0.001) after the index event were significantly higher in the "classical" myocardial infarction group (MICAD)- Despite a shorter overall length of hospital stay (9.5 ± 8.7 days vs. 12.3 ± 10.5 days, p < 0.01) with a significantly shorter duration of high care monitoring (intensive/intermediate care or chest pain units) (2.4 ± 2.1 days vs. 4.7 ± 3.3 days, p < 0.01) MINOCA patients consumed a relevant contingent of hospital resources. Thus, in a 12-months period a total sum of almost 300 days was attributed to high care monitoring for MINOCA patients with a mean difference of approximately 50% compared to patients with classical myocardial infarction. With average and median costs of 50% less per index, MINOCA treatment costs were lower compared to the MICAD group in the hospital reimbursement system of Germany. Consequently, MINOCA treatment was not associated with a relevant profit for these expanses and a relevant share of nearly 40% of the total costs was generated due to high care monitoring.

Conclusion

In light of lower mortality than MICAD and growing scarcity of staff, financial and capacity resources the clinical symptom complex of MINOCA should be put under particular consideration for refining care concepts and resource allocation.

Helicobacter pylori and Pro-Inflammatory Protein Biomarkers in Myocardial Infarction with and without Obstructive Coronary Artery Disease

Myocardial infarction (MI) with obstructive coronary artery disease (MI-CAD) and MI in the absence of obstructive coronary artery disease (MINOCA) affect different populations and may have separate pathophysiological mechanisms, with greater inflammatory activity in MINOCA compared to MI-CAD. Helicobacter pylori (Hp) can cause systemic inflammation and has been associated with cardiovascular disease (CVD). We aimed to investigate whether Hp infection is associated with concentrations of protein biomarkers of inflammation and CVD. In a case-control study, patients with MINOCA (n = 99) in Sweden were included, complemented by matched subjects with MI-CAD (n = 99) and controls (n = 100). Protein biomarkers were measured with a proximity extension assay in plasma samples collected 3 months after MI. The seroprevalence of Hp and cytotoxin-associated gene A (CagA) was determined using ELISA. The associations between protein levels and Hp status were studied with linear regression. The prevalence of Hp was 20.2%, 19.2%, and 16.0% for MINOCA, MI-CAD, and controls, respectively (p = 0.73). Seven proteins were associated with Hp in an adjusted model: tissue plasminogen activator (tPA), interleukin-6 (IL-6), myeloperoxidase (MPO), TNF-related activation-induced cytokine (TRANCE), pappalysin-1 (PAPPA), soluble urokinase plasminogen activator receptor (suPAR), and P-selectin glycoprotein ligand 1 (PSGL-1). Hp infection was present in one in five patients with MI, irrespective of the presence of obstructive CAD. Inflammatory proteins were elevated in Hp-positive subjects, thus not ruling out that Hp may promote an inflammatory response and potentially contribute to the development of CVD.

Polygenic risk scores point toward potential genetic mechanisms of type 2 myocardial infarction in people with HIV

BACKGROUND

People with human immunodeficiency virus (HIV) infection (PWH) are at higher risk of myocardial infarction (MI) than those without HIV. About half of MIs in PWH are type 2 (T2MI), resulting from mismatch between myocardial oxygen supply and demand, in contrast to type 1 MI (T1MI), which is due to primary plaque rupture or coronary thrombosis. Despite worse survival and rising incidence in the general population, evidence-based treatment recommendations for T2MI are lacking. We used polygenic risk scores (PRS) to explore genetic mechanisms of T2MI compared to T1MI in PWH.

METHODS

We derived 115 PRS for MI-related traits in 9541 PWH enrolled in the Centers for AIDS Research Network of Integrated Clinical Systems cohort with adjudicated T1MI and T2MI. We applied multivariate logistic regression analyses to determine the association with T1MI and T2MI. Based on initial findings, we performed gene set enrichment analysis of the top variants composing PRS associated with T2MI.

RESULTS

We found that T1MI was strongly associated with PRS for cardiovascular disease, lipid profiles, and metabolic traits. In contrast, PRS for alcohol dependence and cholecystitis, significantly enriched in energy metabolism pathways, were predictive of T2MI risk. The association remained after the adjustment for actual alcohol consumption.

CONCLUSIONS

We demonstrate distinct genetic traits associated with T1MI and T2MI among PWH further highlighting their etiological differences and supporting the role of energy regulation in T2MI pathogenesis.

Why the Term MINOCA Does Not Provide Conceptual Clarity for Actionable Decision-Making in Patients with Myocardial Infarction with No Obstructive Coronary Artery Disease

When acute myocardial injury is found in a clinical setting suggestive of myocardial ischemia, the event is labeled as acute myocardial infarction (MI), and the absence of ≥50% coronary stenosis at angiography or greater leads to the working diagnosis of myocardial infarction with non-obstructed coronary arteries (MINOCA). Determining the mechanism of MINOCA and excluding other possible causes for cardiac troponin elevation has notable implications for tailoring secondary prevention measures aimed at improving the overall prognosis of acute MI. The aim of this review is to increase the awareness that establishing the underlying cause of a MINOCA is possible in the vast majority of cases, and that the proper classification of any MI should be pursued. The initial diagnosis of MINOCA can be confirmed or ruled out based on the results of subsequent investigations. Indeed, a comprehensive clinical evaluation at the time of presentation, followed by a dedicated diagnostic work-up, might lead to the identification of the pathophysiologic abnormality leading to MI in almost all cases initially labeled as MINOCA. When a specific cause of acute MI is identified, cardiologists are urged to transition from the "all-inclusive" term "MINOCA" to the proper classification of any MI, as evidence now exists that MINOCA does not provide conceptual clarity for actionable decision-making in MI with angiographically normal coronary arteries.

Chlamydia pneumoniae and Mycoplasma pneumoniae as two Emerging Risk Factors in Atherosclerosis: Meta-Analysis Study and Systematic Review

BACKGROUND

Previous studies suggested an association between Chlamydia pneumoniae and Mycoplasma pneumonia with atherosclerosis, separately. Until now, according to inconsistent information, the relationship between C.pneumoniae and M.pneumoniae with atherosclerosis is controversial.

OBJECTIVE

the aim of this study, investigate of the association between C.pneumoniae and M.pneumoniae as two separate risk factors with atherosclerosis by systematic review and meta-analysis study.

METHODS

We searched databases such as Pubmed, SID, Magiran, Google scholar and Iranmedex using the following keywords in English and Persian language as C. pneumoniae , M. pneumoniae and atherosclerosis. Data were analyzed with meta-analysis and a random effect model. Also, in this study Heterogeneity of articles were estimated by using I2 index. Finally, data was analyzed with STAT (version 11.2) Results: Among thirty-eight articles for C. pneumoniae and five articles for M. pneumoniae individually reviewed that included 2980 samples for M. pneumoniae and 23298 samples for C. pneumoniae, result demonstrated that association between M. pneumoniae and C. pneumoniae with atherosclerosis is significant with OR (odd ratio) = 1.58 (95% Confidence Interval (CI): 1.00 to 2.50), OR (odd ratio) = 2.25(95% Confidence Interval (CI): 1.91 to 2.64), respectively.

CONCLUSION

This systematic review study provides strong evidence for the role of persistent bacterial infection such as M. pneumoniae and C. pneumoniae in potential atherosclerosis. Thus, a novel way should be employed for the complete management of bacterial infection.

Preliminary study: myocardial T1 relaxation time in patients with ischemic findings and normal findings on coronary angiography

OBJECTIVE

The aim of this study is to evaluate the myocardium structure in patients with chest pain who were determined to have moderate and/or high risk for cardiac ischemic heart disease (IHD) but who had normal findings on conventional coronary angiography by using native cardiac magnetic resonance imaging (CMRI) T1 mapping and comparing with healthy volunteers.

METHODS

A total of 50 patients and 30 healthy volunteers who underwent CMRI were included in our prospective study. Patients whose clinical findings were compatible with stable angina pectoris, with moderate and/or high risk for IHD, but whose conventional coronary angiography was normal, were our patient group. Native T1 values were measured for 17 myocardial segments (segmented based on American Heart Association recommendations) by two radiologists independently. The data obtained were statistically compared with the sample t-test.

RESULTS

Myocardial native T1 values were found to be significantly prolonged in the patient group compared with the control group (p<0.05). Inter-observer reliability for native T1 value measurements of groups was high for both patient and control groups (α = 0.92 for the patient group and 0.96 for the control group).

CONCLUSION

Findings suggestive of ischemia were detected by T1 mapping in the myocardium of our patients. For this reason, it is recommended that this patient group should be included in early diagnosis and close follow-up assessments for IHD.

Risk factor comparison in young patients presenting with acute coronary syndrome with atherosclerotic coronary artery disease vs. angiographically normal coronaries

Background: Acute myocardial infarction is a relatively rare phenomenon in the young population. The incidence has nevertheless increased from years past, likely due to the presence of multiple risk factors from an increasingly younger age. Regardless of whether they have atherosclerotic coronary artery disease or normal coronary angiogram, young patients with risk factors for coronary artery disease (CAD), chest pain, and positive troponin, are initially treated in a similar fashion. Our goal was to shed light on whether risk factors between these two groups differ to help guide physicians in clinically determining whether or not an atherosclerotic cardiovascular event has occurred, as well as to potentially identify young patients at risk of acute coronary syndrome (ACS) despite normal coronary arteries. Methods: A retrospective cross sectional study was undertaken over an 8 year period at Tawam Hospital. 576 patients aged 50 or under who underwent coronary angiography were selected for the study. Medical records were analyzed for the patient's demographics and CAD risk factor profile, including the following variables: family history of CAD, smoking status, Body Mass Index category, lipid profile, and diagnosis of hyperlipidemia, diabetes, or hypertension. Details of the coronary angiogram were also reviewed. Results: Statistically significant outcomes included a higher prevalence of diabetes, hyperlipidemia, and smoking history in patients with CAD compared to the patients with normal coronary angiogram. Diabetes was one of the strongest risk factors in CAD patients, with an odds ratio of 1.98 (p= 0.011), followed by hyperlipidemia at 1.85 (p= 0.021). Smoking history had an odds ratio of 2.93 (p <0.001). Conclusion: Risk factors were present in both groups, but significantly more in the CAD group. No particular risk factor stood out for the development of ACS in those with normal coronary arteries, other than mean BMI being slightly higher in this group. Based on our analysis, no single variable can accurately predict the risk for ACS in normal coronaries. To our knowledge, few studies have been done in the young population with angiographically normal coronary arteries to determine possible risk factors for development of ACS. Further research needs to be done to determine whether the risk factors that were common amongst both groups are coincidental, or a cause of ACS in those with normal coronary arteries.

Role of cardiovascular magnetic resonance in the prognosis of patients with myocardial infarction with non-obstructive coronary arteries

BACKGROUND

It is estimated that 5% to 10% of patients with myocardial infarction (MI) present with no obstructive coronary artery lesions. Until now, most studies have focused on acute coronary syndrome, including different clinical entities with a similar presentation encompassed under the term MINOCA (MI with non-obstructive coronary arteries). The aim of this study is to assess the prognosis of patients diagnosed with true infarction, confirmed by cardiovascular magnetic resonance (CMR), in the absence of significant coronary lesions.

METHODS

Prospective multicenter registry study, including 120 consecutive patients with a CMR-confirmed MI without obstructive coronary artery lesions. The primary clinical outcome was major adverse cardiovascular events (MACE: death, non-fatal infarction, stroke, or cardiac readmission), assessed over three years.

RESULTS

Seventy-six patients (63.3%) were admitted with a diagnosis of acute coronary syndrome, and 44 (36.6%) for other causes (mainly heart failure); the definitive diagnosis was established by CMR. Most patients (64.2%) were men, and the mean age was 58.8 ± 13.5 years. Patients presented with small infarcts: 83 (69.1%) showed late gadolinium enhancement (LGE) in one or two myocardial segments, mainly transmural (in 77.5% of patients) and with a preserved left ventricular ejection fraction (median 54.8%, interquartile range 37-62). The most frequent infarct location was inferolateral (n = 38, 31.7%). During follow-up, 43 patients (35.8%) experienced a MACE, including 9 (7.5%) who died. In multivariable analysis, LGE in two versus one myocardial segment doubled the risk of adverse cardiac events (hazard ratio [HR] 2.32, 95% confidence interval [CI] 0.97-5.83, p = 0.058). Involvement of three or more myocardial segments almost tripled the risk (HR 2.71, 95% CI 1.04-7.04, p = 0.040 respectively).

CONCLUSIONS

Patients with true MI but without significant coronary artery lesions predominantly had small infarcts. Myocardial 3-segment LGE involvement is associated with a significantly higher risk of adverse cardiac events.

Myocardial infarct size and sex-related angiographic differences in myocardial infarction in nonobstructive coronary artery disease

BACKGROUND

Myocardial infarction in nonobstructive coronary artery disease (MINOCA) is a recently described infarct subtype. There are few studies that examine coronary artery disease (CAD) extent, MI size and type, and treatment differences at hospital discharge compared to myocardial infarction in obstructive coronary artery disease (MICAD), or that explore sex-specific MINOCA attributes of coronary anatomy and infarct size.

METHODS

Our study population consisted of a single tertiary-center of consecutive patients that had coronary angiography for acute MI between 2005 and 2015. The MI type at presentation, MI size and ejection fraction (post-MI), and gender differences between MINOCA patients were examined.

RESULT

Among 1698 cases with acute MI, 95 had MINOCA (5.6%). MINOCA patients were younger, more often had NSTEMI, lower peak cardiac troponin (cTn) values, and greater ejection fraction than MICAD patients (all P-values <0.005). At hospital discharge, 30-day re-admission rates were similar. MINOCA patients less frequently received optimal medical therapy. When women were analyzed, the 45 women with MINOCA had smaller MIs (P < 0.001) and greater ejection fraction (P = 0.002) than the 358 women with MICAD. Sex comparisons of the 95 MINOCA patients revealed women were older than men (P < 0.001), had lower mean peak cTn values (P < 0.001), greater ejection fraction (P = 0.02), and more single-vessel disease involvement than men (P < 0.0001).

CONCLUSION

The average MI size is smaller in MINOCA than MICAD patients, and there are sex-related differences in clinical presentation, coronary artery disease extent, and MI size. Re-admission rates are similar and MINOCA patients are less likely to receive guideline recommended medical therapy at discharge.

Outcome after myocardial infarction without obstructive coronary artery disease

OBJECTIVE

The medium-term outcome and cause of death in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) is not well characterised. The aim of this study was to compare mortality and rates of recurrent events in post myocardial infarction (MI) patients with obstructive coronary artery disease (CAD) and in patients with MINOCA compared with an age and sex-matched cohort without cardiovascular disease (CVD).

METHODS

We performed a national cohort study of consecutive patients undergoing coronary angiography for MI during 2 years between 2013 and 2015 from the All New Zealand Acute Coronary Syndrome-Quality Improvement (ANZACS QI) registry. MI patient registry data were linked anonymously to national hospitalisation and mortality records. Age and sex matched patients without known CVD formed the comparison group.

RESULTS

Of the 8305 patients with MI, 897 (10.8%) were classified as MINOCA. Compared with those without known CVD, the adjusted HRs for the primary outcome (all-cause death or recurrent non-fatal MI) were 7.81 (95% CI 6.64 to 9.19, p<0.0001) in those with obstructive CAD and 4.64 (95% CI 3.54 to 6.10, p<0.0001) in those with MINOCA. Kaplan-Meier all-cause mortality at 2 years was 7.9% for those with obstructive CAD, with nearly half being CVD deaths (3.6% CVD deaths and 4.5% non-CVD deaths, respectively). In contrast, MINOCA all-cause mortality was 4.9% with non-CVD death (4.5%) predominating.

CONCLUSIONS

MINOCA is common and has an adverse outcome rate approximately half than that of those with obstructive CAD. The predominant contributor to mortality is non-CVD death. The rate of events in MINOCA is significantly greater than the population without CVD.

The occupational risk of Helicobacter pylori infection: a systematic review

PURPOSE

The aim of this systematic review was to describe the prevalence of Helicobacter pylori infection in specific occupational groups and to compare them with the general population.

METHODS

We searched PubMed® to identify original studies reporting the prevalence of H. pylori infection in occupational groups. The differences between occupational groups and the general population were analyzed taking into account the direction and statistical significance of the differences observed when comparing each occupational group with a reference group (either recruited in the same study or using an external comparator).

RESULTS

A total of 98 studies addressing the prevalence of H. pylori infection in occupational groups were included in the systematic review. Overall, health professionals showed a significantly higher prevalence of H. pylori infection than the general population, especially among those working at gastrointestinal units. Similar results were found in subjects involved in agricultural, forestry and fishery, as well as in sewage workers, miners, and workers at institutions for the intellectually disabled, although differences were less pronounced.

CONCLUSIONS

Our results show an occupational risk of H. pylori infection supporting the role of oral-oral, fecal-oral, and zoonotic transmission. Studies comparing specific occupational groups with adequate comparators may contribute to better identify groups at higher risk of infection. The recognition of this infection as an occupational disease would result in early detection and treatment, as well as prevention and control of its transmission in workplaces.

Uncommon cause of complicated myocardial infarction with normal coronary arteries in a Saudi patient

A case of a young Saudi patient with a previous diagnosis of bronchial asthma, nasal polyps, and chronic smoker, presented with atypical chest pain, elevated serum troponin and borderline ischemic electrocardiogram (ECG) changes, with no significant regional wall motion abnormalities at bedside echocardiography is reported. The patient was admitted to the coronary care unit for continuous monitoring as possible acute coronary syndrome, non-ST elevation myocardial infarction (STEMI). One hour after admission, the patient had ventricular fibrillation (VF) cardiac arrest that required three DC shocks and amiodarone bolus before returning of spontaneous circulation, which followed the fourth shock. The resuscitation took 15 minutes of cardiopulmonary resuscitation (CPR). An immediate 12-leads ECG showed significant ST elevation in precordial leads that mandate an urgent coronary angiogram that revealed patent coronary arteries, therefore spasm of normal coronary arteries was postulated as the operative factor. The cardiac magnetic resonance image (MRI) showed a picture of transmural anterior myocardial infarction, which correlates with the follow up echocardiogram reporting hypokinetic anterior wall. A complete history was taken and no use of illicit drugs or alcohol was found. The unusual presentation in such a patient with evidence of extensive anterior STEMI and normal coronary arteries raise the thought of considering uncommon causes. In view of previous medical history and laboratory evidence of eosinophilia, Kounis syndrome was considered dominant in the differential diagnosis.

Epidemiology of Myocardial Infarction Caused by Presumed Paradoxical Embolism via a Patent Foramen Ovale

BACKGROUND

Despite several negative prospective randomized trials on the efficacy of patent foramen ovale (PFO) occlusion, the discussion on indications is ongoing. Because the incidence of paradoxical coronary embolism through a PFO is unknown, we investigated the risk of paradoxical embolic myocardial infarction over a period of 13 years.

METHODS AND RESULTS

We conducted a retrospective and a prospective study. In the former, we searched the hospital database of a tertiary referral center for cases of acute myocardial infarction (AMI) during the past 10 years and screened them for possible paradoxical MIs. On this basis we started a prospective evaluation over 39 months in another tertiary referral center. All patients with AMI and normal coronary arteries were screened for PFO and if no other reason for the AMI could be found, the case was judged as presumed paradoxical embolism. In the retrospective analysis we found 22 cases (0.45%) of presumed paradoxical coronary artery embolism under 4,848 AMI. In the prospective study there were 11 presumed paradoxical coronary artery embolisms among 1,654 patients with AMI, representing an incidence of 0.67%.

CONCLUSIONS

Our findings demonstrated that well below 1% of AMIs are caused by paradoxical embolism via an interatrial communication. Although this percentage appears low, it is not a negligible number of patients based on the huge number of MIs occurring in the industrialized world.

Congenital coronary artery anomalies in adults: review of 111 cases from a single-centre experience

BACKGROUND

Coronary artery anomalies are a heterogeneous group of congenital disorders presenting with a wide spectrum of symptoms, ranging from vague chest pain to sudden cardiac death. Despite available data, there is no consensus about the classification, nomenclature, and outcomes of coronary anomalies in the normally connected heart. In this study, we aimed to investigate clinical and angiographic characteristics of coronary arterial anomalies, as well as the frequency of atherosclerotic involvement in anomalous coronaries, diagnosed at a tertiary referral centre.

METHODS

We retrospectively reviewed coronary angiograms performed between 2011 and 2015 for the presence of a coronary anomaly. A total of 111 patients with a final diagnosis of coronary anomaly were included in the study group. We also recruited 110 age- and sex-matched patients who underwent coronary angiography because of symptomatic coronary artery disease as controls.

RESULTS

Among 36,893 coronary angiograms, 111 (0.30%) major coronary anomalies were found. Compared with controls, the prevalence of significant atherosclerotic coronary disease was lower in patients with coronary anomalies and stable symptoms (p=0.02); however, the prevalence of significant coronary atherosclerosis was similar among patients admitted with unstable angina or myocardial infarction (p>0.05). Compared with controls, patients with an anomalous left anterior descending coronary artery had significantly less atherosclerotic involvement than those in whom the left anterior descending artery was not anomalous (p=0.005).

CONCLUSIONS

Although coronary artery anomalies are cited as a cause for myocardial ischaemia, atherosclerotic coronary artery disease is also frequent and may offer an alternative explanation to ischaemic symptoms. No predisposition to accelerated atherosclerosis was found, however, and atherosclerotic involvement was less frequent in some anomalous vessels.

Myocardial Infarction Without Obstructive Coronary Artery Disease is Not a Benign Condition (ANZACS-QI 10)

BACKGROUND

Non-obstructive coronary artery disease (CAD) on coronary angiography after myocardial infarction (MI) is associated with a lower risk of adverse outcomes, but the prognosis may not be benign. Our aim was to assess outcomes in MI with and without obstructive CAD, and in an age and sex matched comparison cohort without known cardiovascular disease.

METHODS

We performed a single centre analysis of consecutive patients undergoing coronary angiography for MI between 2007 and 2012. Patients were classified into those with obstructive CAD (≥50% epicardial coronary artery stenosis) and those without obstructive CAD (<50%). Myocardial infarction patient data was collected in an electronic registry and linked anonymously to national hospitalisation and mortality records. Age and sex matched patients without known CVD were identified from the community PREDICT cohort.

RESULTS

Of the 2070 patients with MI, 302 (15%) had non-obstructive CAD. Compared to patients with obstructive disease they were younger (mean 57 v 61 years, p<0.001), more likely to be women (50% vs 23%, p<0.001), to be of Maori or Pacific vs. European ethnicity (p<0.001), more likely to be lifelong non-smokers (46% v 38%, p=0.02), non-diabetic (80v 73%, p <0.01), have no ST-segment deviation (78% v 46%, p<0.001), and have a low risk Global Registry of Acute Coronary Events acute coronary syndrome (GRACE ACS) score (54 v 35%, p<0.001). They were also less likely to receive 'triple therapy' secondary prevention medications (81% v 94%, p<0.0001). The cumulative two-year Kaplan-Maier composite outcome of mortality or non-fatal MI was 14.3% for MI with obstructive CAD, 4.6% for MI without obstructive disease, and 2.2% for patients without prior CVD (p<0.001).

CONCLUSION

Myocardial infarction without obstructive coronary disease is common (∼1 in 7 patients) and is not clinically benign, with an adverse outcome rate double that of age and sex matched patients without CVD.

Human cytomegalovirus infection and vascular disease risk: A meta-analysis

BACKGROUND

Human cytomegalovirus (HCMV) infection has been associated with the acceleration of vascular disease. Numbers studies were conducted to analyze the association between HCMV infection and risk of vascular disease, but no clear consensus had been reached. The aim of this study was to confirm this relationship precisely by doing a systematic review and meta-analysis.

METHODS

We identified relevant studies through a search of PubMed and Embase. Studies were eligible for inclusion if they fulfilled all of the following selection criteria: (1) evaluating the association between HCMV infection and vascular disease; (2) case-control studies or nested case-control studies; (3) and supply the numbers (or percentage) of positivity for HCMV infection in cases and controls, respectively. Data were extracted and analyzed independently by two investigators. Ultimately, We included data from 68 studies, which altogether enrolled 12027 cases and 15386 controls from 24 countries.

RESULTS

HCMV IgG was detected 7376 in 10611 cases, HCMV IgM was detected 153 in 1486 cases and HCMV DNA was detected 654 in 2139 cases. Overall, people exposed to HCMV infection had higher risk than those not exposed for vascular disease (OR 1.70 [95% CI 1.43-2.03] IgG-based HCMV tests, 2.88 [95% CI 1.87-4.43] IgM-based HCMV tests and 2.56 [95% CI 1.46-4.49 PCR-based HCMV tests]). HCMV infection was clearly identified as a risk factor for vascular disease in Asian group, Caucasian group and other group, especially Asian group(OR 1.86 [95% CI 1.33-2.60] IgG-based HCMV tests, 3.57 [95% CI 1.94-6.60] IgM-based HCMV tests and 4.09 [95% CI 3.10-5.40 PCR-based HCMV tests]).

CONCLUSION

This meta-analysis suggested that HCMV infection is associated with an increased risk for vascular disease.

Risk Factors and Markers for Acute Myocardial Infarction With Angiographically Normal Coronary Arteries

Myocardial Infarction with normal coronary arteries (MINCA) is common with a prevalence of 1% to 12% of all myocardial infarctions. The pathogenic mechanisms of MINCA are still unknown, but endothelial dysfunction has been suggested as a possible cause. To investigate risk factors and markers for MINCA, we conducted a case-control study. Considering the reported low prevalence of classical risk factors for coronary heart disease (CHD) in some but not all studies, our hypothesis was that endothelial function and intima-media thickness (IMT) were better, respectively lower, than CHD controls. One hundred patients with MINCA fulfilling diagnostic criteria according to the European Society of Cardiology/American Collage of Cardiology/American Heart Association universal definition of myocardial infarction with myocarditis excluded by cardiac magnetic resonance imaging were investigated. Risk factors, endothelial function (EndoPAT), and IMT were compared to gender- and age-matched patients with myocardial infarction and CHD, respectively healthy controls. Smoking, hypertension, impaired glucose tolerance and diabetes mellitus, inflammatory disease, and psychiatric disorders were more common in patients with MINCA than in healthy controls. In contrast to patients with CHD, the lipid profile was antiatherogenic with low low-density lipoprotein and high high-density lipoprotein cholesterol. There were no major differences between the groups regarding endothelial function and IMT that were in the normal range. In conclusion, the present study showed that MINCA was associated with many established cardiovascular risk factors without major differences in atherosclerosis markers. MINCA patients recalled a high prevalence of emotional stress before admission that together with previous psychiatric vulnerability and female gender speaks strongly in favor of Takotsubo syndrome being an important cause of MINCA.

Systematic review of patients presenting with suspected myocardial infarction and nonobstructive coronary arteries

BACKGROUND

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a puzzling clinical entity with no previous evaluation of the literature. This systematic review aims to (1) quantify the prevalence, risk factors, and 12-month prognosis in patients with MINOCA, and (2) evaluate potential pathophysiological mechanisms underlying this disorder.

METHODS AND RESULTS

Quantitative assessment of 28 publications using a meta-analytic approach evaluated the prevalence, clinical features, and prognosis of MINOCA. The prevalence of MINOCA was 6% [95% confidence interval, 5%-7%] with a median patient age of 55 years (95% confidence interval, 51-59 years) and 40% women. However, in comparison with those with myocardial infarction associated with obstructive coronary artery disease, the patients with MINOCA were more likely to be younger and female but less likely to have hyperlipidemia, although other cardiovascular risk factors were similar. All-cause mortality at 12 months was lower in MINOCA (4.7%; 95% confidence interval, 2.6%-6.9%) compared with myocardial infarction associated with obstructive coronary artery disease (6.7%, 95% confidence interval, 4.3%-9.0%). Qualitative assessment of 46 publications evaluating the underlying pathophysiology responsible for MINOCA revealed the presence of a typical myocardial infarct on cardiac magnetic resonance imaging in only 24% of patients, with myocarditis occurring in 33% and no significant abnormality in 26%. Coronary artery spasm was inducible in 27% of MINOCA patients, and thrombophilia disorders were detected in 14%.

CONCLUSIONS

MINOCA should be considered as a working diagnosis with multiple potential causes that require evaluation so that directed therapies may improve its guarded prognosis.

Five-year mortality and coronary heart disease development after normal coronary angiogram

BACKGROUND

Previous studies depict low cardiac event and mortality rates in patients with angiographically normal coronary arteries. These studies, however, are limited by small sample sizes, short follow-up intervals, and selection biases. This study was undertaken to determine the natural five-year course of a diverse cohort of subjects with documented normal coronary arteries with respect to coronary heart disease development, revascularization need, and all-cause mortality.

METHODS

Consecutive adult patients with angiographically normal coronary arteries were followed up for 5 years through medical record review. Patients with any degree of angiographic abnormality, including minimal luminal irregularity or non-critical stenosis, were excluded. Patients were not excluded based on age, co-morbidities (except cardiac transplant and structural heart disease), indication for angiogram, or initial hospitalization status.

RESULTS

Normal coronary arteries were found in 182 (31.3%) of 582 patients; 129 met all inclusion criteria. The mean age was (49.1±12.5) years; 47 (36.7%) were male and 75 (58.1%) were caucasian. The most common indication for angiography was cumulative risk factors (60.5%). Within 5 years of a normal angiogram, 13 of 129 patients died (10.1%; 95 CI 5.7%-16.9%). Six (40%; 95 CI 19.8% to 64.3%) of 15 patients undergoing repeat angiogram within five years developed new coronary heart disease, with one requiring revascularization. Of traditional risk factors of coronary heart disease, only diabetes was associated with a higher risk of death.

CONCLUSION

The natural five-year course of a diverse cohort of patients with documented normal coronary arteries suggests that there is significant risk for death and development of coronary heart disease.

Chlamydophila pneumoniae infection and cardiovascular disease

Atherosclerosis is a multifactorial vascular inflammatory process; however, the inciting cause for inflammation remains unclear. Two decades ago, Chlamydophila pneumoniae (formerly Chlamydia pneumoniae) infection was proposed as a putative etiologic agent. We performed a PubMed search using the keywords Chlamydia and atherosclerosis in a Boolean query to identify published studies on C. pneumoniae and its role in atherogenesis, and to understand research interest in this topic. We found 1,652 published articles on this topic between 1991 and 2011. We analyzed relevant published studies and found various serological, molecular, and animal modeling studies in the early period. Encouraged by positive results from these studies, more than a dozen antibiotic clinical-trials were subsequently conducted, which did not find clinical benefits of anti-Chlamydophila drug therapy. While many researchers believe that the organism is still important, negative clinical trials had a similar impact on overall research interest. With many novel mechanisms identified for atherogenesis, there is a need for newer paradigms in Chlamydophila-atherosclerosis research.

Prognostic role of Helicobacter pylori infection in acute coronary syndrome: a prospective cohort study

Abstract

In a prospective cohort study, we evaluated the effect of Helicobacter pylori seropositivity on the risk of future adverse cardiovascular outcomes among patients with acute coronary syndrome (ACS). In 433 patients, IgA and IgG antibodies to H pylori, along with classic risk factors, including hypertension, diabetes, hyperlipidaemia, smoking and family history of coronary artery disease (CAD) were determined. Short-and long-term follow-up information on adverse outcomes, defined as recurrence of unstable angina, myocardial infarction, coronary angioplasty, coronary artery bypass graft surgery, and sudden cardiac death was obtained. None of the classic CAD risk factors correlated with incidence of either short- or long-term outcomes. Seropositivity for H pylori was significantly associated with risk of short-term adverse outcomes, and independently predicted their incidence in multivariate regression (R = 3.05, p < 0.001). Results failed to show such an association between H pylori seropositivity and long-term adverse outcomes. H pylori infection may affect short-term prognosis in patients with ACS. Randomised trials are needed to evaluate the role of H pylori eradication in these patients.

Frequency of Helicobacter pylori and cytotoxine associated gene A antibodies in patients with cardiac syndrome X

Background:

Cardiac syndrome X (CSX) is a condition in which patients have the pain of angina despite normal coronary angiogram. Recently, Helicobacter pylori (H. pylori) bacteria has been associated with CSX. However, there is no obvious data about the frequency of its virulent strain (cytotoxine associated gene A: CagA) in patients with CSX. We surveyed the frequency of H. pylori and CagA antibodies in patients with cardiac syndrome X and healthy controls.

Materials and Methods:

Plasma samples from 100 CSX patients (61 females and 39 males; mean age: 51.8 ± 12.3 years) and 100 healthy controls (61 females and 39 males; mean age: 48.9 ± 6.3 years) were tested for the presence of IgG antibody to H. pylori using enzyme linked immunosorbent assay (ELISA) method. Also, infected patients were determined by the presence of IgG antibody to CagA by ELISA method. Statistical analysis was carried out using chi-square test and independent samples T-test.

Results:

Ninety two percent (92/100) of patients were anti-H. pylori positive (anti-H. pylori+), while only 56.0% (56/100) of control group were anti-H. pylori+ (P<0.01). However, prevalence of anti-CagA positive (anti- CagA+) in H. pylori infected- CSX patients and control groups were 59.8% (55/92) and 60.7% (34/56), respectively (P>0.05).

Conclusion:

Thus, due to the high frequency of anti-H. pylori in CSX patients, and the probable causative effect of chronic infection in vascular diseases, it is suggested that H. pylori has a probable role in the pathogenesis of CSX.

Is Myocardial Infarction in Patients without Significant Stenosis on a Coronary Angiogram as Benign as Believed?

The present study aimed to investigate the clinical characteristics and 1-year outcomes of acute myocardial infarction (AMI) patients without significant stenosis on a coronary angiogram comparison with the clinical characteristics and outcomes of patients with significant coronary artery stenosis. A total of 1,220 patients with AMI were retrospectively classified into Group I (≥50% diameter stenosis, n=1,120) and Group II (<50%, n=100). Group II was further divided into two subgroups according to the underlying etiology: cryptogenic (Group II-a, n=54) and those with possible causative factors (Group II-b, n=46). Patients in Group II were younger, were more likely to be women, and were less likely to smoke and to have diabetes mellitus than were patients in Group I. The levels of cardiac enzymes, LDL-cholesterol levels, and the apo-B/A1 ratio were lower in Group II. However, 1-month and 12-month rates of major adverse cardiac events (MACE) were not significantly different between the two groups. The Group II-b subgroup comprised 29 patients with vasospasm, 11 with myocardial bridge, and 6 with spontaneous thrombolysis. Left ventricular ejection fraction and creatinine clearance were lower and levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hs-CRP) were higher in Group II-a than in Group II-b. However, outcomes including MACE and mortality at 12 months were not significantly different between the two subgroups. The 1-year outcomes of patients in Group II were similar to those of patients in Group I. The clinical outcomes in Group II-a were also similar to those of Group II-b, although the former group showed higher levels of NT-proBNP and hs-CRP.

Cytomegalovirus infection and coronary heart disease risk: a meta-analysis

The chronic inflammatory process including cytomegalovirus (CMV) infection has been hypothesized to induce the progression of atherosclerosis in coronary heart disease (CHD). Numbers studies were conducted to analyze the association between CMV infection and risk of CHD, but no clear consensus had been reached. To assess this relationship more precisely, a meta-analysis was performed. The electronic databases PubMed, Embase, and CNKI were searched; data were extracted and analyzed independently by two investigators. Ultimately, 55 studies, involving 9,000 cases and 8,608 controls from six prospective studies (all with a nested case-control design) and 49 retrospective case-control studies were included. Overall, people exposed to CMV infection had an odds ratio (OR) of 1.67 (95% CI, 1.56-1.79) for CHD risk, relative to those not exposed. CMV infection was clearly identified as a risk factor for CHD in both prospective studies (OR, 1.31; 95% CI, 1.132-1.517) and retrospective studies (OR, 1.79; 95% CI, 1.659-1.939), and in both Asian group (OR, 2.69; 95% CI, 2.304-3.144) and non-Asian group (OR, 1.48; 95% CI, 1.371-1.600). Interestingly, in the subgroup analyses by detection methods of CMV, the increased risk (OR, 8.121) was greater among studies using polymerase chain reaction than the risk (OR, 1.561) among studies using enzyme-linked immunosorbent assay. In conclusion, this meta-analysis suggested that CMV infection is associated with an increased risk for CHD, especially among Asian populations.

Coronary CT angiography: current status and continuing challenges

Coronary CT angiography has been increasingly used in the diagnosis of coronary artery disease owing to rapid technological developments, which are reflected in the improved spatial and temporal resolution of the images. High diagnostic accuracy has been achieved with multislice CT scanners (64 slice and higher), and in selected patients coronary CT angiography is regarded as a reliable alternative to invasive coronary angiography. With high-quality coronary CT imaging increasingly being performed, patients can benefit from an imaging modality that provides a rapid and accurate diagnosis while avoiding an invasive procedure. Despite the tremendous contributions of coronary CT angiography to cardiac imaging, study results reported in the literature should be interpreted with caution as there are some limitations existing within the study design or related to patient risk factors. In addition, some attention must be given to the potential health risks associated with the ionising radiation received during cardiac CT examinations. Radiation dose associated with coronary CT angiography has raised serious concerns in the literature, as the risk of developing malignancy is not negligible. Various dose-saving strategies have been implemented, with some of the strategies resulting in significant dose reduction. The aim of this review is to present an overview of the role of coronary CT angiography on cardiac imaging, with focus on coronary artery disease in terms of the diagnostic and prognostic value of coronary CT angiography. Various approaches for dose reduction commonly recommended in the literature are discussed. Limitations of coronary CT angiography are identified. Finally, future directions and challenges with the use of coronary CT angiography are highlighted.

The natural course of traumatic myocardial infarction in a young patient with angiographically normal coronary arteries

A 23-year-old man with no history of heart disease was admitted to Beijing Anzhen Hospital Affiliated to Capital Medical University for an abnormal electrocardiogram of ST-T changes mimicking myocardial infarction. Catheterization revealed normal coronary and peripheral arteries. The echocardiogram and delayed enhancement cardiovascular magnetic resonance imaging indicated a markedly reduced left ventricular function and enlarged left ventricular cavity with evidence of fibrous tissue. Given the patient's history of multiple blunt trauma 7 years previously and acute myocardial infarction diagnosis at that time, he was diagnosed with traumatic myocardial infarction (TMI). We describe the natural course of such a patient with TMI. There is a possibility of spontaneous healing of coronary artery dissection induced by trauma. Although early revascularization may be helpful for preventing cardiac remodeling after TMI in some cases, more data are needed to compare the long-term outcome among different interventions in large sample cases.

Evolution of acute coronary syndrome with normal coronary arteries and normal cardiac magnetic resonance imaging

BACKGROUND

Acute coronary syndrome (ACS) with normal coronary angiography is a frequent clinical situation with an uncertain prognosis. Cardiac magnetic resonance imaging (CMRI) is a powerful tool for differential diagnosis between myocardial infarction (MI), acute myocarditis and Tako-tsubo cardiomyopathy (TTC). Data are sparse regarding the evolution of patients presenting an ACS with normal coronary arteries and normal CMRI.

AIMS

To evaluate the evolution of patients presenting an ACS with normal coronary arteries and normal CMRI, with a 1-year follow-up.

METHODS

Eighty-seven consecutive patients (mean age, 53 years; 40.2% men) presenting an ACS with troponin elevation and normal coronary arteries by angiography were prospectively included. All patients underwent CMRI at 3-Tesla. Adverse events were recorded with 1-year follow-up.

RESULTS

A likely aetiology for the acute clinical presentation was established by CMRI in 63.2% of patients (22.7% MI, 26.4% acute myocarditis, 11.5% TTC). During follow-up, one patient in the MI group had a stroke (1.2%). In the myocarditis group, there was one initial cardiogenic shock, one episode of congestive heart failure (1.2%) and nine patients had recurrent chest pain without troponin elevation (10.3%). Two TTC group patients initially presented with cardiogenic shock (2.4%); there were no other adverse events in this group during follow-up. In the remaining 36.7% patients, no clear diagnosis could be identified by CMRI, and no adverse events occurred during follow-up.

CONCLUSION

CMRI is a useful tool for the management of ACS presenting with normal coronary angiography, as it helps to ascertain the diagnosis and adapt treatment in a large proportion of cases. Nonetheless, patients with no abnormalities identified by CMRI have an excellent evolution.

ST-segment elevation in non-atherosclerotic coronaries: a brief overview

The most common, clinically significant cause of ST elevation is an angiographically demonstrable occlusive disease due to atherosclerotic changes in coronary artery. Often, a patient presenting with non-specific complaints and ST-segment elevation on the electrocardiogram, is sent for a cardiac catheterization only to see no luminal stenosis on the angiogram. This clinical review is intended to inform emergency medicine physicians and internists about the conditions in which ST-segment elevation is accompanied with no atherosclerotic lesion on coronary angiography. These situations make a diverse array of conditions ranging from anomalous coronaries to anatomically normal coronaries with varied degrees of myocardial injury. These conditions are briefly reviewed in this article.

Coronary artery disease in asymptomatic young adults: its prevalence according to coronary artery disease risk stratification and the CT characteristics

Objective

We aimed at evaluating the prevalence and CT characteristics of occult coronary artery disease (CAD) in young Korean adults under 40 years of age by performing coronary CT angiography (CCTA).

Materials and Methods

We retrospectively enrolled 112 consecutive asymptomatic subjects (90 men, mean age: 35.6 ± 3.7 years) who underwent CCTA as part of a general health evaluation. We classified the subjects into three National Cholesterol Education Program risk categories and we assessed the plaque characteristics on CCTA according to the number of involved vessels, the location and type of plaques and vascular remodeling.

Results

Twelve individuals had CAD (11%, 11 men). The prevalence of CAD was significantly higher in the subgroups with moderate (22%) or high (25%) risk than that in the low risk subgroup (5%) (p < 0.05). Nine patients had single-vessel disease and three patients had two-vessel disease. The most common location for plaque was the proximal left anterior descending coronary artery (60%). All the patients had non-significant stenosis and plaque, including the non-calcified (27%), mixed (47%) and calcified (27%) types. Positive vascular remodeling was identified in all the patients with non-calcified or mixed plaques.

Conclusion

The prevalence of occult CAD was not negligible in the asymptomatic young adults with moderate to high risk, and this suggests the importance of management and risk factor modification in this population. All the patients had non-significant stenosis, and one fourth of the plaques did not show calcification.

Cardiac complication after experimental human malaria infection: a case report

A 20 year-old healthy female volunteer participated in a clinical Phase I and IIa safety and efficacy trial with candidate malaria vaccine PfLSA-3-rec adjuvanted with aluminium hydroxide. Eleven weeks after the third and last immunization she was experimentally infected by bites of Plasmodium falciparum-infected mosquitoes. When the thick blood smear became positive, at day 11, she was treated with artemether/lumefantrine according to protocol. On day 16 post-infection i.e. two days after completion of treatment, she woke up with retrosternal chest pain. She was diagnosed as acute coronary syndrome and treated accordingly. She recovered quickly and her follow-up was uneventful. Whether the event was related to the study procedures such as the preceding vaccinations, malaria infection or antimalarial drugs remains elusive. However, the relation in time with the experimental malaria infection and apparent absence of an underlying condition makes the infection the most probable trigger. This is in striking contrast, however, with the millions of malaria cases each year and the fact that such complication has never been reported in the literature. The rare occurrence of cardiac events with any of the preceding study procedures may even support a coincidental finding.

Apart from acute coronary syndrome, myocarditis can be considered as a final diagnosis, but the true nature and patho-physiological explanation of the event remain unclear.

MR delayed enhancement imaging findings in suspected acute myocarditis

The purpose of the study was to prospectively assess the clinical impact of routinely performed delayed enhancement imaging in suspected acute myocarditis. A two-centre prospective study was performed in patients with suspected acute myocarditis. The protocol included horizontal long axis, vertical long axis and short axis ciné MR and delayed enhancement imaging after Gd-DTPA infusion (0.2 mmol/kg). Sixty consecutive patients were enrolled (aged 49.4 +/- 17.8 years). MRI demonstrated delayed enhancement sparing the subendocardicardial layer in 51.6% of patients, concordant with the diagnosis of acute myocarditis; 16.7% of patients exhibited delayed enhancement involving the subendocardial layer with irregular margins, concordant with the diagnosis of acute myocardial infarction; 31.7% of patients had delayed enhancement imaging that was considered normal. Routine imaging to identify delayed enhancement provided crucial information in suspected acute myocarditis by reinforcing the diagnosis in 51.6% of patients and correcting a misdiagnosed acute myocardial infarction in 16.7% of patients.

Possible causes of symptoms in suspected coronary heart disease but normal angiograms

BACKGROUND

In patients with suspected coronary heart disease and normal angiography, the causes of cardiac symptoms frequently remain undetermined. A correct diagnosis is desirable, however, since some of the underlying disorders may be curable, treatable, influence prognosis, or induce screening of the relatives.

HYPOTHESIS

In such patients, the prevalence of arterial hypertension, hemochromatosis, hypothyroidism, hypoparathyroidism, tachycardiomyopathy, amyloidosis, and neuromuscular disorders as a possible cause for their symptoms and the seroprevalence of micro-organisms, known to cause myocardial damage, were assessed.

METHODS

Consecutive patients with normal coronary angiograms were invited for two visits comprising clinical history and investigation, electrocardiograms, blood tests, and echocardiography. Patients were investigated neurologically if unexplained anginal chest pain or creatine kinase elevation persisted or if echocardiography showed isolated left ventricular abnormal trabeculations.

RESULTS

In 71 patients (31 women, 40 men, mean age 60 years), the most common cause for cardiac symptoms was hypertension (66%), followed by neuromuscular disorders (13%), tachycardiomyopathy (9%), hypothyroidism (4%), and hemochromatosis (3%). The seroprevalence for Chlamydia species was 90%, Helicobacter pylori 70%, Chlamydia pneumoniae 63%, Borrelia burgdorferi sensu lato 15%, and Rickettsia conorii 10%. No possible cause was found in 24% of the patients.

CONCLUSIONS

In patients with suspected coronary heart disease and normal angiograms, hypertension, neuromuscular disorders, tachycardiomyopathy, hypothyroidism, and hemochromatosis should be considered as possible causes.

Platelet deposition in rabbit common carotid arteries promoted by arterial stenosisand spasm. A quantitative and morphological study

Coronary arteriograhy in patients with ischemic heart disease often shows spasm of the coronary arteries. The question is whether spasm is a triggering factor for thrombosis in a stenotic artery. If so, what are the mechanisms for this? A stenosing teflon ring was applied to the right common carotid artery of anesthetized rabbits and 1-nor-epinephrine was dripped over the outer surface of both carotid arteries, causing spasm. In control animals an indifferent solution did not cause spasm. Nineteen rabbits were killed 30 min or 24 h after treatment. Microscopically, arteries with stenosis and spasm contained thrombi nearby the stenosis significantly more often than arteries in control animals. In another 14 rabbits, killed at 30 min, the number of platelets on the intimal surface away from the stenosis was quantified. In arteries with both stenosis and spasm the counts were significantly greater than in arteries with no treatment. The intimal surface in stenotic and spastic arteries showed assumed imprints of eddying flow and endothelial injury downstream and upstream of the stenosis. Spastic arteries showed increased folding of the internal elastic membrane, altered endothelial cells, and adhering platelets. Spasm in a rabbit artery with a preformed stenosis facilitates thrombosis probably by creating increased flow disturbances. Spasm may induce endothelial injury, causing adherence of platelets.

Elevated infection parameters and infection symptoms predict an acute coronary event

Background: The etiology and significance of flu-like symptoms often appearing before myocardial infarction should be clarified.

Methods: In a case-control study of 323 matched controls and a random sample of 110 out of 351 cases the presence of infection symptoms during the preceding four weeks before admission were asked and blood samples taken.

Results: Enterovirus (EV), herpes simplex virus (HSV), and Chlamydia pneumoniae IgA titers were significantly higher in cases than in controls ( p<0.001, 0.008 and 0.046, respectively). Flu-like symptoms appeared significantly more often in patients than in controls the most common one being fatigue ( p<0.001). In controls with fatigue, EV and HSV titers showed a trend to be higher (1.50 vs 1.45 and 4.29 vs 3.73) than in controls without fatigue but only HSV titers were statistically significantly higher (3.47 vs 3.96, p = 0.02). Even CRP and amyloid A concentrations (3.49 vs 2.08, p<0.0001 and 5.70 vs 3.77 mg/l, p = 0.003, respectively) as well as C4 (0.40 vs 0.44, p = 0.02) were higher in controls with fatigue.

Conclusions: Odds ratios for a coronary event in a logistic regression model were 4.79 for fatigue and 2.72 for EV antibody levels in their fourth quartile. A linear-by-linear association test showed increasing number of single symptoms with higher EV titer quartiles ( p = 0.004).

Myocardial infarction with angiographically normal coronary arteries in the contemporary era

BACKGROUND

Myocardial infarction with angiographically normal coronary arteries (MINC) is a well recognized clinical entity, but limited data regarding outcome and prognostic factors exist in the literature. This study sought to identify clinical characteristics and etiological factors as well as outcome predictors in patients with MINC.

DESIGN

Retrospective follow-up study.

METHODS

Fifty-eight patients presenting with MINC fulfilled the study inclusion criteria. Clinical characteristics, cardiovascular risk factors, and etiologic and laboratory data were harvested and compared with those obtained from patients with myocardial infarction and single vessel coronary artery disease (MISVD). Follow-up information regarding survival and cardiac events such as angina, reinfarction and heart failure was collected and prognostic factors identified.

RESULTS

Compared with the MISVD group, MINC patients had a lower prevalence of hypercholesterolemia and ST elevation. Hypercoagulopathy, collagen tissue disorder, cocaine abuse and Takotsubo cardiomyopathy were identified etiologies in some MINC patients. During follow-up, patients with MINC were less likely to sustain reinfarction (log-rank P<0.001) and cardiovascular death (log-rank P=0.04) on Kaplan-Meier survival analysis. Recurrence of angina and heart failure were the most prevalent cardiac events in the MINC group. Cox proportional multivariate regression analysis identified left ventricular ejection fraction as an independent predictor of cardiac events in the MINC cohort.

CONCLUSION

MINC is associated with lower mortality and morbidity compared with infarction in the setting of single vessel disease. Left ventricular function is an independent predictor of poor outcome.

Effect of atherosclerosis on thermo-mechanical properties of arterial wall and its repercussion on plaque instability

Data from the literature report febrile reactions prior to myocardial infarction in patients with normal coronary arteries and that coronary syndromes seem to be triggered by bacterial and viral infections, being fever the common symptom. The thermo-mechanical behavior of thoracic aortas of New Zealand White rabbits with different degrees of atherosclerosis was measured by means of pressure-diameter tests at different temperatures. Specific measurements of the thermal dilatation coefficient of atheroma plaques were performed by means of tensile tests. Results show a different thermo-mechanical behavior, the dilatation coefficient of atheroma plaque being at least twice that of the arterial wall. Temperature-induced mechanical stress at the plaque-vessel interface could be enough to promote plaque rupture. Therefore, increases of corporal temperature, either local or systemic, can play a role in increasing the risk of acute coronary syndromes and deserve a more comprehensive study.

Antiphospholipid antibodies in patients with coronary artery disease: new cardiac risk factors?

Antiphospholipid antibodies (aPL) have been implicated in the pathogenesis of coronary artery disease (CAD). We evaluated the presence of aPL in patients with chest pain/acute coronary syndromes (ACS) to determine if aPL were associated with the presence and severity of CAD, adverse outcomes, and other coronary risk factors. Patients with chest pain/ACS were evaluated for aPL prior to diagnostic and therapeutic investigations. Coronary angiograms were graded according to the severity of disease. Risk factors, including family histories, were assessed and patients were followed for adverse outcomes. To date, 232 patients (116 M, 116 F, mean age 63 years) with a mean follow-up of 9 months were studied. Thirty-seven percent (86/232) were positive for one or more aPL. More women, 49/86 (57%), were aPL positive versus men, 37/86 (43%). The presence of aPL appeared associated with both presence and severity of CAD (P = 0.176 women; P = 0.163 men). In patients undergoing procedures (angioplasty, stent, bypass), aPL was significantly associated with both an increase in adverse cardiac outcomes (P = 0.045) and extracardiac thrombotic events (P = 0.033). Anti-beta2 glycoprotein-1 (abeta2GP1) was the most frequent aPL, occurring in 68.5% of aPL-positive patients with CAD. Anticardiolipin antibody (aCL) occurred in only 7.4%. IgM isotypes were the most frequent for all categories of aPL (range 55-90%). Family history of antiphospholipid syndrome (APS)-related events was more significant in aPL-positive than aPL-negative individuals (P = 0.027).

Acute ST elevation myocardial infarction with angiographically normal coronary arteries: causes and outcomes

A minority of patients presenting with ST elevation myocardial infarction (STEMI) have angiographically normal coronary arteries. We aimed to assess its incidence, identify possible aetiologies and determine long-term prognosis. We retrospectively analysed 714 consecutive patients presenting with STEMI over a 10-year period (1995 to 2005), and identified 41 patients with angiographically normal coronary arteries. Mean age was 44+/-15 years; the majority were male. Specific diagnoses were made in 13/41 (32%) patients, including peri-myocarditis (11/41) and Takotsubo cardiomyopathy (2/41). No specific diagnosis was made in the remainder and these were considered cryptogenic AMI's. At a mean follow-up of 44+/-30 months, 1 patient with cryptogenic AMI had a non-cardiovascular death and 1 patient required pacing. In conclusion, there is a small but definite incidence of angiographically normal coronary arteries in patients presenting with STEMI. While the eventual aetiology remains uncertain in most patients, long-term outcomes appear favourable.

Myocardial infarction with normal coronary arteries: a conundrum with multiple aetiologies and variable prognosis: an update

The existence of myocardial infarction despite angiographically normal coronary arteries was recognized more than 30 years ago. Since then, various series of such patients have been described, but the aetiology and pathogenesis of the condition are still a source of debate. Evidence exists for a role of coronary vasospasm, thrombosis, embolization and inflammation, per se or combined, in determining the occurrence of myocardial infarction in the presence of angiographically normal coronary arteries. Endothelial dysfunction, possibly superimposed to nonangiographically evident atherosclerosis, may be an underlying common feature predisposing to the acute event. Additionally, myocarditis may explain some of these occurrences. Myocardial infarction with normal coronary arteries is therefore likely the result of multiple pathogenetic mechanisms. Although most reports emphasize the good prognosis of this condition, in general much better than myocardial infarction with coronary artery disease, prognosis is likely variable according to the underlying mechanism. This review summarizes current knowledge on this condition and examines areas of recent progress.

Normal coronary arteries are rare in young patients with acute myocardial infarction

OBJECTIVE

To delineate the angiographic extent of coronary atherosclerosis in young patients (<45 years) with acute myocardial infarction (MI).

BACKGROUND

Prior studies suggest 20% of young patients with acute MI have normal coronary arteries. However, most such studies defined "normal" as absence of stenoses >50% luminal diameter, ignoring the presence of nonflow limiting disease that may harbor culprit plaques.

METHODS

We retrospectively analyzed 131 patients <45 years old with ST-segment elevation MI undergoing emergency catheterization. Angiograms were analyzed for the presence and extent of disease, including lesion "complexity" indicative of plaque instability. "Normal" vessels were defined as absence of any disease.

RESULTS

Mean patient age was 40 +/- 7 years. The infarct related artery and an obvious complex culprit lesion was identified in all (100%) cases (left anterior descending 44%, right coronary 38%, and circumflex 18%). Single vessel disease involving the culprit vessel only was identified in 60% of cases, whereas additional disease was found in 40% of others (two-vessel in 29% and three-vessel disease in 11% of patients).

CONCLUSION

These findings demonstrate that young patients with acute MI typically manifest an identifiable complex culprit atherosclerotic coronary lesion. Furthermore, they often have multivessel atherosclerosis.