Myocardial infarction and normal coronary arteriography: a 10 year clinical and risk analysis of 74 patients

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.

Acute myocardial infarction not attributed to coronary artery disease: A seldom initial presentation of a left ventricular myxoma

Although myxoma represents the most frequent non-malignant cardiac primary tumor; it is extremely rare met in the left ventricle. Clinical features of the neoplasm extend from symptomless to critical signs of either ischemia or embolism. We describe here an unusual case of a huge left ventricular myxoma in a 68-year-old man, presented with clinical and ECG findings of an inferior wall myocardial infarction. The patient was primarily referred to our institution for coronary angiography, which showed no coronary artery disease. Further examinations revealed a left ventricular mass as the possible source of embolization, thus the patient underwent surgery for tumor excision. The postoperative course was unremarkable. A bibliographical analysis demonstrated that those tumors are rare but treatable causes of embolic myocardial infarction, thus profound clinical intuition, proper utilization of imaging modalities, administration of anticoagulants preoperatively, as well immediate surgical removal are justified.

Posterobasal left ventricular aneurysm after myocardial infarction with normal coronary arteries: Case-report

We present a case of a 64-year-old woman with signs of debilitating condition including anginal chest pain, exertional dyspnea, and depression. The patient had previously suffered from a myocardial infarction after a loss of a close family member. Workup showed a posterobasal left ventricular aneurysm and moderate to severe mitral regurgitation in the absence of coronary atherosclerosis. Routine ultrasonography revealed abdominal aortic aneurysm and intraabdominal aortic deviation. The patient was immediately started on optimal medical treatment. On repeat assessment general condition was satisfactory, vital signs were normal, and investigations showed no signs of progressive heart failure or other significant clinical changes. Although prognosis in patients with myocardial infarction with normal coronary arteries is generally considered favorable, mechanical complications such as posterobasal left ventricular aneurysm with moderate to severe mitral regurgitation are possible.

Risk of ventricular arrhythmia in patients with myocardial infarction and non-obstructive coronary arteries and normal ejection fraction

AIM

To assess the arrhythmic determinants and prognosis of patients presenting with myocardial infarction and non-obstructive coronary arteries (MINOCA) with normal ejection fraction (EF).

METHODS

This is an observational analysis of 131 MINOCA patients with normal EF. Three cardiac magnetic resonance (CMR) diagnosis classes were recognized according to the late gadolinium enhancement (LGE) pattern: Myocardial infarction (MI) (n = 34), myocarditis (n = 47), and “no LGE” (n = 50). Ventricular events occurring during hospitalization were recorded and the entire population was followed-up at 1 year.

RESULTS

Ventricular arrhythmia was observed in 18 (13.8%) patients during hospitalization. The “no LGE” patients experienced fewer ventricular events than the MI and myocarditis patients [4.0% vs 26.5% and 14.9%, respectively (P = 0.013)]. There was no significant difference between the MI and myocarditis groups. On multivariate analysis, LGE transmural extent [OR = 1.52 (1.08-2.15), P = 0.017] and ST-segment elevation [OR = 4.65 (1.61-13.40), P = 0.004] were independent predictors of ventricular arrhythmic events, irrespective of the diagnosis class. Finally, no patient experienced sudden cardiac death or ventricular arrhythmia recurrence at 1-year.

CONCLUSION

MINOCA patients with normal EF presented no 1-year cardiovascular events, irrespective of the CMR diagnosis class. LGE transmural extent and ST segment elevation at admission are risk markers of ventricular arrhythmia during hospitalization.

Nonobstructive Versus Obstructive Coronary Artery Disease in Acute Coronary Syndrome: A Meta-Analysis

Background

Differences in prognosis and baseline clinical presentation have been documented among patient with acute coronary syndrome and coronary artery disease with obstructive (ObCAD) or nonobstructive arteries (NObCAD), but the rates of events largely varied across single studies. We carried out a meta‐analysis to compare the clinical presentation and prognosis of NObCAD versus ObCAD acute coronary syndrome patients, as well as of the subjects with zero versus mild occlusion.

Methods and Results

Searches were made in MedLine, EMBASE, Cochrane databases, and proceedings of international meetings up to June 30, 2015. We compared the risk of events of NObCAD versus ObCAD patients using random‐effect meta‐analyses. We also performed meta‐analyses to estimate the yearly or monthly outcome rates in each single group. In NObCAD and ObCAD patients, respectively, the combined yearly rates were as follows: 2.4% versus 10.1% (all‐cause mortality); 1.2% versus 6.0% (myocardial infarction), 4.0% versus 12.8% (all‐cause mortality plus myocardial infarction), 1.4% versus 5.9% (cardiac death), and 9.2% versus 16.8% (major cardiovascular events). In the studies directly comparing NObCAD versus ObCAD, all of the above outcomes were significantly less frequent in NObCAD subjects (with risk ratios ranging from 0.33 to 0.66). No differences in any outcome rate were observed between mild occlusion (1–49% stenosis) and zero occlusion patients.

Conclusions

NObCAD in patients with acute coronary syndrome has a significantly lower cardiovascular risk at baseline and a subsequent lower likelihood of death or main cardiovascular events. However, these subjects are still at high risk for cardiovascular mortality and morbidity, suggesting potential undertreatment and calling for specific management.

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.

Myocardial infarction with normal coronary arteries is common and associated with normal findings on cardiovascular magnetic resonance imaging: results from the Stockholm Myocardial Infarction with Normal Coronaries study

OBJECTIVES

Myocardial infarction with angiographically normal coronary arteries (MINCA) is an important subtype of myocardial infarction; however, the prevalence, underlying pathophysiology, prognosis and optimal management of this condition are still largely unknown. Cardiovascular magnetic resonance (CMR) imaging has the potential to clarify the underlying pathology in patients with MINCA. The objective of this study was to investigate the diagnostic value of CMR imaging in this group of patients.

DESIGN

The prospective, multicentre, observational Stockholm Myocardial Infarction with Normal Coronaries (SMINC) study.

SETTING

Coronary care units in the Stockholm metropolitan area.

SUBJECTS

Patients between 35 and 70 years of age with MINCA were consecutively included in the screening phase of the SMINC study. All patients had a typical clinical presentation, fulfilling the universal definition of myocardial infarction and had normal coronary angiography finding. Patients with known structural or coronary heart disease or other known causes of elevated troponin levels were excluded.

RESULTS

In total, 176 patients with MINCA were screened from 2007 to 2011. Of these, 152 underwent CMR imaging. The investigation was performed a median of 12 (interquartile range 6-28) days after hospital admission; 67% of the findings were normal, whereas 19% of patients had signs of myocardial necrosis and 7% had signs of myocarditis. The remaining patients (7%) had either unrecognized hypertrophic cardiomyopathy or could not be classified.

CONCLUSION

In this consecutive series of patients with MINCA, CMR imaging may help to differentiate between those with myocarditis, myocardial necrosis and normal myocardium. The incidence of MINCA was higher than previously reported. After excluding cases of myocarditis, MINCA consists of a large group of patients with normal CMR imaging results and a smaller group with myocardial necrosis. The aetiologies of these different imaging findings need to be explored.

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.

Risk factors for myocardial infarction with normal coronary arteries and myocarditis compared with myocardial infarction with coronary artery stenosis

The interest and awareness of myocardial infarction with normal coronary arteries (MINCA) have increased recently due to the frequent use of coronary angiography, the description of Takotsubo stress cardiomyopathy, and new sensitive troponin analyses. The prevalence of MINCA in all patients with myocardial infarction (MI) was registered during a 3-month period in the Stockholm metropolitan area in Sweden. The results showed that MINCA is more common than previously thought (7%) and affecting one third of every woman with MI. Patients with myocarditis were younger and more often presented with signs of inflammation such as elevated C-reactive protein and fever. Myocarditis constitutes an important differential diagnosis for coronary artery disease. There is a need for larger studies of MINCA, including investigation with cardiac magnetic resonance imaging, to establish prevalence and pathological process in this important subgroup of MI.

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.

Coexistence of acute myocardial infarction with normal coronary arteries and migraine with aura in a female patient

Acute myocardial infarction with normal coronary arteries is a well known condition, which is typically diagnosed in young patients. Coronary vasospasm, inherited, acquired or malignancy-induced hypercoagulable state, collagen vascular disease and coronary arterial embolism have been considered as underlying etiologic factors. An association between migraine with aura and increased risk of ischemic stroke, angina and myocardial infarction has been demonstrated in studies. Patients with migraine and especially with aura should be followed closely against cardiovascular events even if they are young and do not have traditional risk factors.

Myocardial infarction with angiographically normal coronary arteries

Myocardial Infarction with Normal Coronary Arteries (MINCA) is an important subgroup of myocardial infarction with a frequency of at least 3-4% of all myocardial infarctions. The interest and awareness of MINCA have increased recently due to the frequent use of coronary angiography, the description of Takotsubo stress cardiomyopathy and new sensitive troponin assays. Since myocarditis may mimic myocardial infarction it is essential to exclude this in patients with myocardial infarction with angiographically normal coronary arteries. Cardiac magnetic resonance imaging is a cornerstone not only to establish the diagnosis but also an important tool in the search for different causes of myocardial damage. In the future, atherosclerotic burden, hemostatic function, characterization of stressors and inflammation will be important targets for research in this group of patients.

Cardiac syndrome X: current concepts

Cardiac syndrome X is a heterogeneous entity, both clinically and pathophysiologically, encompassing a variety of pathogenic mechanisms. Management of this syndrome represents a major challenge to the treating physician. They often seek medical care because of recurring and disabling chest pain, which may imply repetitive and costly invasive and non-invasive investigations. A careful patient evaluation for underlying pathophysiologic mechanism and exclusion of other causes of chest pain along with attention to various psychological aspects is helpful in reducing the stress and suffering of these patients. This article reviews the available literature on the pathophysiology and current controversies surrounding the management of this difficult to treat condition.

Intracoronary catheter aspiration can be an adequate option in patients with acute myocardial infarction caused by left atrial myxoma

Cardiac myxomas are the most common benign cardiac tumors and can be associated with systemic embolization including acute myocardial infarction (AMI). The probability of an arterial embolization is closely related to a tumor's villous morphology. In cases of AMI caused by cardiac myxoma, open heart surgery including excision of the coronary artery has been the one of the treatment options for removing the myxoma and embolus from the coronary artery to maintain distal coronary flow. However, preparing for emergent open heart surgery takes a considerable amount of time. Moreover, this time delay can deteriorate the coronary perfusion to the infarcted area and is associated with poor clinical prognosis. So intracoronary catheter aspiration can be an additional option to maintain the distal coronary flow. In this report we present a case with acute anterior ST elevation myocardial infarction caused by a left atrial myxoma. The embolus in the left anterior descending coronary artery was successfully removed with intracoronary catheter aspiration, and distal coronary flow was restored after the procedure.

Acute ST-segment elevation myocardial infarction due to a huge floating thrombus mimicking a myxoma in the left atrium

Acute ST-segment elevation myocardial infarction occurs when the blood supply to a coronary artery is completely interrupted. The most common cause of the abrupt occlusion of a coronary artery is the rupture of a vulnerable atherosclerotic plaque. However, embolisms from any sources can be another cause of abrupt coronary obstruction. The authors report a case of acute ST-segment elevation myocardial infarction caused by a huge left atrial thrombus mimicking a myxoma.

Are patients with angiographically near-normal coronary arteries who present as acute myocardial infarction actually safe?

BACKGROUND

There is a paucity of data concerning the clinical outcome of patients presenting with acute myocardial infarction (AMI) and near-normal coronary angiograms. The purpose of this study was to evaluate the clinical outcome and the prognosis of the patients with near-normal coronary angiograms who were registered in the Korean Acute Myocardial Infarction Registry (KAMIR).

METHODS

The subjects were divided into three groups according to findings from coronary angiograms performed between September 2005 and November 2006. Among 8510 consecutive AMI patients, 372 patients (Group I) had near-normal coronary arteries, 6136 patients (Group II) had one- or two-vessel disease, and 2002 patients (Group III) had three-vessel or left main disease.

RESULTS

Clinical characteristics, in-hospital mortality, and major cardiac adverse events (MACE) were analyzed. Group I was younger, had the lower prevalence of DM, and showed the higher percentage of previous angina history compared to the other two groups. Group III showed a higher incidence of in-hospital mortality, but there was no significant difference between Group I and Group II (2.6% in Group II and 2.2% in Group I, p=0.952). Furthermore, MACE at 1 month, 6 months and 12 months revealed no significant difference between Groups I and II (12 month MACE: 7.8% in Group I and 12.2% in Group II, p=0.359).

CONCLUSIONS

Patients with near-normal coronary angiograms had similar clinical outcomes and prognosis compared with one- or two-vessel diseased patients presenting with an acute myocardial infarction.

Acute myocardial infarction in the presence of normal coronaries and the absence of risk factors in a young, lifelong regular exerciser

Around 6% of patients suffering an acute myocardial infarction (AMI) have normal coronary arteries. The mechanisms responsible are not fully known, but include hypercoagulable state, coronary endothelial dysfunction, aortic dissection, inflammation, coronary thrombosis, aortic wall stiffening, cocaine abuse, carbon monoxide poisoning and paradoxical embolism. Here, the case of a lifelong regular exerciser without risk factors for cardiovascular disease who suffered an AMI with normal coronaries is reported. Despite normal cardiac function on left ventriculography and echocardiography, late gadolinium enhancement by cardiac magnetic resonance (CMR) revealed significant cardiac necrosis. The long-term prognosis is favourable with low rates of coronary morbidity and mortality. Acute chest pain should not be considered as benign and warrants medical investigation.

Baseline clinical characteristics and midterm prognosis of STE-ACS and NSTE-ACS patients with normal coronary arteries

OBJECTIVE

We sought to compare clinical profiles and midterm prognosis of patients with normal coronary arteries presenting with ST-elevation ACS (STE-ACS) versus non-ST-elevation ACS (nSTE-ACS).

BACKGROUND

There are limited data regarding ACS in patients with normal coronary arteries, and especially clinical differences between ST-ACS and nSTE-ACS patients have not been evaluated sufficiently.

METHODS

The study group comprised 190 patients (mean age: 53.2 years, 63.1% males, 63.6% STE-ACS) presenting with ACS and normal coronary angiograms. The participants were evaluated in terms of 42 clinical variables. MACE [cardiac death (CD) and hospitalization for angina (HA)] were the study end points.

RESULTS

STE-ACS in comparison to nSTE-ACS patients were younger (P < 0.01), were more frequently males (P < 0.01), had more often infection prior to ACS (P < 0.01), higher hsCRP on admission (P < 0.01), and greater infarct size, measured by maximal troponin I (P < 0.01). By multivariate analysis in this subgroup, predictors of outcome were hsCRP (P = 0.03) and raised troponin I (P = 0.02). nSTE-ACS in comparison to STE-ACS patients were more obese (BMI, P < 0.01), had higher LDL cholesterol (P < 0.01), fasting glucose (P = 0.03). LDL cholesterol (P = 0.02) and fasting glucose (P = 0.03) emerged as independent predictors of outcome in these patients. Mean follow-up period was 25.4 months. STE-ACS patients had twice fewer MACE rate than nSTE-ACS patients [(1-CD, 12-HA; 11%) vs (1-CD, 16-HA; 25%), respectively, log rank P < 0.01].

CONCLUSIONS

STE-ACS and nSTE-ACS patients with normal coronary arteriography have different clinical profiles. In nSTE-ACS patients more pronounced metabolic abnormalities were identified, while in STE-ACS patients inflammatory background was more significant.

Myocardial infarction with normal coronary arteries: a case report and review of the literature

Introduction

Although acute myocardial infarction is generally associated with obstructive coronary artery disease, myocardial infarction associated with normal coronary arteries is a well-known condition. The overall prevalence rate of myocardial infarction with normal coronary arteries is considered to be low, varying from 1% to12% depending on the definition of "normal" coronary arteries.

Case presentation

We describe here a case of a 49-year-old woman with a history of prior myocardial infarction who continued to be asymptomatic after a 10-year follow-up, in the absence of a high-risk profile for adverse outcomes. She was studied with multi-slice coronary computed tomography and whole-body angiography, which showed normal coronary and extra-coronary arteries.

Conclusion

This case report raises two important issues. First, the possible role of multi-slice computed tomography/coronary angiography in the risk- and prognosis assessment of patients with known or suspected coronary artery disease. Second, the important role played by long-term pharmacological therapy in patients with prior myocardial infarction and normal coronary arteries.

Conditions mimicking acute ST-segment elevation myocardial infarction in patients referred for primary percutaneous coronary intervention

BACKGROUND/OBJECTIVES.: A rapid diagnosis of ST-segment elevation myocardial infarction (STEMI) is mandatory for optimal treatment. However, a small proportion of patients with suspected STEMI suffer from other conditions. Although case reports have described these conditions, a contemporary systematic analysis is lacking. We report the incidence, clinical characteristics and outcome of patients with suspected STEMI referred for primary percutaneous coronary intervention (PCI) with a final diagnosis other than STEMI. METHODS.: From January 2004 to July 2005, 820 consecutive patients were included with suspected STEMI who were referred for primary PCI to a university medical centre, based on a predefined protocol. Clinical characteristics, final diagnosis and outcome were obtained from patient charts and databases. RESULTS.: In 19 patients (2.3%), a final diagnosis other than myocardial infarction was established: coronary aneurysm (n=1), (myo)pericarditis (n=5), cardiomyopathy (n=2), Brugada syndrome (n=1), aortic stenosis (n=1), aortic dissection (n=3), subarachnoidal haemorrhage (n=2), pneumonia (n=1), chronic obstructive pulmonary disease (n=1), mediastinal tumour (n=1), and peritonitis after recent abdominal surgery (n=1). These patients less often reported previous symptoms of angina (p<0.001), smoking (p<0.05) and a positive family history of cardiovascular diseases (p<0.05) than STEMI patients. Mortality at 30 days was 16%. CONCLUSION.: A 2.3% incidence of conditions mimicking STEMI was found in patients referred for primary PCI. A high clinical suspicion of conditions mimicking STEMI remains necessary. (Neth Heart J 2008;16:325-31.).

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.

Stress-induced cardiomyopathy: A review

In clinical practice it is essential to bear stress-induced cardiomyopathy (SICMP) in mind as it is an insufficiently known cardiac pathology that mimics acute coronary syndromes (ACS), often with signs of cardiac failure. In the chronic phase, it poses differential diagnostic problems with regard to coronary artery pathology. Taxonomic confusion, due to the pathology also being called "takotsubo" or "ampulla cardiomyopathy", has resulted in inappropriate diagnoses and therapy. Available evidence strongly suggests that, in the presence of several cardiac risk factors, excessive sympathetic stimulation may induce this cardiomyopathy. The predilection of this cardiomyopathy for Mediterranean and Indo-Asian women, who represent 85% of cases, is probably explained by the fact that there is a significant correlation between female gender, a short (<158 cm) stature, a small (<1.9 m(2)) body surface area, and hypoplastic coronary arteries. Furthermore, 40% of SICMP patients have a hypoplastic branching of the coronary arteries in the apical region of the heart. This anomaly strongly favors the apical localization of the dyskinesia. The prognosis of SICMP is good as far as life expectancy is concerned. However, in most cases, the symptoms become chronic, medical treatment rarely improves dyspnea and chest pain, and the quality of life is, therefore, reduced. In this paper, we address diagnostic misunderstandings and we review the clinical and pathophysiological features of SICMP.

Assessment of arterial distensibility in patients with cardiac syndrome X

This study aims to investigate arterial distensibility by using carotid-femoral (aortic) pulse wave velocity measurements in patients with cardiac syndrome X. The authors studied 10 patients with cardiac syndrome X (mean age 49.4 +/-7.5, 39 to 67 years old, 3 men) and 10 healthy subjects (mean age 50.0 +/-10.5, 38 to 70 years old, 3 men). Carotid-femoral pulse wave velocity measured by a Complior Colson device was calculated for each patient. The carotid-femoral pulse wave velocity was increased in patients with cardiac syndrome X as compared with age-matched control subjects (10.25 +/-1.28 vs 8.95 +/-0.89 m/s, p = 0.01). In contrast, there were no significant differences in the age, weight, height, body mass index, waist/hip ratio, systolic blood pressure, diastolic blood pressure, mean blood pressure, pulse pressure, and heart rate (p=0.76,p=0.17,p=0.36,p=0.08, p=0.21,p=0.14,p=0.89,p=0.30,p=0.10, p = 0.36, respectively). No significant correlation was found between pulse wave velocity and age, sex, height, weight, heart rate, systolic blood pressure, diastolic blood pressure, mean blood pressure, and pulse pressure in the studied groups (p>0.05). The arterial distensibility was decreased in patients with cardiac syndrome X. The deterioration in these patients showed that this disease might be a more generalized disturbance of the vasculature. Measurements of carotid-femoral pulse wave velocity may provide a simple and noninvasive technique to identify patients at increased risk of vascular disease.

Detection of myocarditis by contrast-enhanced MRI in patients presenting with acute coronary syndrome but no coronary stenosis

PURPOSE

To prospectively assess the use of cardiac MRI with delayed contrast enhancement (DCE) for identifying patients with active myocarditis among those presenting with acute coronary syndrome (ACS) but no coronary stenosis.

MATERIALS AND METHODS

A total of 27 consecutive patients (age = 45 +/- 17 years; 14 male) presenting with ACS (chest pain, positive troponin-I) and no coronary stenosis, underwent cardiac MRI 9 +/- 7 days after pain onset and 8 +/- 5 months later (N = 19). Steady-state free-precession pulse (SSFP) sequence was applied for the assessment of myocardial function and both inversion-recovery (IR) and SSFP sequences were used for analyzing the topography and extent of DCE areas. Rest sestamibi-gated-single photon emission CT (SPECT) was also systematically performed.

RESULTS

Subepicardial DCE pattern typical of acute myocarditis was documented in 12 patients (44%). Ischemic DCE pattern (transmural or subendocardial focal DCE) was documented in 12 of the 15 remaining patients (44%). Patients with subepicardial DCE had: higher C-reactive protein (CRP) levels (38 +/- 32 vs. 14 +/- 24 mg/mL; P = 0.04), lower Framingham cardiovascular risk (3 +/- 3% vs. 9 +/- 5%; P < 0.001), lower incidence of perfusion SPECT defects (17% vs. 73%; P = 0.01), higher left ventricular (LV) end-diastolic volume (77 +/- 16 vs. 64 +/- 10 mL/m(2); P = 0.02), and higher regression of DCE areas at follow-up (-65 +/- 17% vs. -18 +/- 23%; P = 0.002).

CONCLUSION

DCE pattern of active myocarditis can be seen in patients presenting with ACS but no coronary stenosis.

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.

Peripartum myocardial ischemia: a review of Canadian deliveries from 1970 to 1998

OBJECTIVE

The purpose of this study was to evaluate the incidence of peripartum myocardial ischemia in Canada.

STUDY DESIGN

We identified the cohort of women who were admitted to Canadian hospitals for delivery between 1970 and 1998 to calculate the incidence rate and to evaluate potential risk factors.

RESULTS

One hundred fourteen of 10,032,375 women delivered in Canadian hospitals between 1970 and 1998 had peripartum myocardial ischemia recorded as a discharge diagnosis. The overall crude incidence rate was 1.1 (95% confidence interval 0.93, 1.37) women with peripartum myocardial ischemia per 100,000 women delivering per year as noted in the Canadian Hospital Morbidity database. Rates did not increase over time but increased with maternal age. Identified risk factors were diabetes mellitus, hyperlipidemia, and chronic heart disease. The case fatality rate among women with the disease was 1.8%.

CONCLUSION

The incidence of peripartum myocardial ischemia did not increase between 1970 and 1998 in Canada, despite an aging cohort with more prevalent medical comorbidities. Maternal mortality from this event is lower than previously described.

Acute myocardial infarction in systemic sclerosis patients: a case series

To characterize the clinical manifestations of patients with systemic sclerosis who develop a myocardial infarction (MI), a retrospective review of the medical records of all patients who were admitted to our institution between 1982 and 2002 and had the dual diagnosis of systemic sclerosis and an acute MI was done. From 1,009 systemic sclerosis hospital admissions, 11 (1.09%) were for an acute MI. Three of these patients had normal coronaries, and instead of wall motion abnormalities, left ventricular hypertrophy was the predominant finding of an echocardiography. The odds ratio of finding normal coronaries in systemic sclerosis vs the general population who develops an acute MI is 33.89 (14.08-81.39). Seven of our patients had an elevated creatinine level on presentation. Acute MI is an uncommon manifestation in systemic sclerosis patients. Normal coronaries are seen more commonly in these patients as compared to the general population, while vascular, gastrointestinal, and renal involvement is prevalent in these patients.

Increased thrombolysis in myocardial infarction frame count in patients with myocardial infarction and normal coronary arteriogram: a possible link between slow coronary flow and myocardial infarction

BACKGROUND

Thrombolysis in myocardial infarction (TIMI) frame count is a simple clinical tool for assessing quantitative indexes of coronary blood flow. This technique counts the number of cineangiographic frames from initial contrast opacification of the proximal coronary artery to opacification of distal arterial landmarks. We hypothesized that patients with normal coronary artery (NCA) and myocardial infarction (MI) might have impaired coronary flow. Accordingly, we assessed the TIMI frame counts of patients with NCA and MI and compared to patients with NCA and without MI.

MATERIALS AND METHOD

This retrospective study included consecutive patients with MI and who were found to have normal coronary angiograms performed between 1999 and 2003. Fifty patients (group I) with NCA and MI were enrolled in the study. Fifty consecutive patients with NCA and without MI were also enrolled in the study as control group (group II). Mean time interval between MI and coronary angiography was 6 +/- 2 days.

RESULTS

There were statistically significant differences between groups I and II in respect to gender (11 females (22%) versus 22 females (44%), p = 0.003, respectively) and smoking status (62% (31/50) versus 38% (19/50), p = 0.02). Comparison of TIMI frame counts between two groups revealed that group I patients had significantly higher TIMI frame counts than group two patients for all three coronary arteries (LAD: 40 +/- 12 versus 23 +/- 7, Cx: 47 +/- 14 versus 27 +/- 7, RCA: 36 +/- 10 versus 26 +/- 10, respectively, p < 0.001 for all). Smokers were significantly younger when compared to non-smokers (44 +/- 5 years versus 51 +/- 9 years, p = 0.008, respectively). TIMI frame counts of smokers did not significantly differ from those of non-smokers in group I patients. There were statistically significant differences between smokers and non-smokers in group II patients regarding TIMI frame counts for all three coronary arteries (LAD: 29 +/- 7 versus 18 +/- 3, LCX: 34 +/- 10 versus 22 +/- 4, RCA: 34+ /- 13 versus 20 +/- 4, respectively, p < 0.001 for all).

CONCLUSION

We have shown that patients with MI and NCA have higher TIMI frame counts for all coronary arteries when compared to patients without MI and NCA. Absence of difference between smokers and non-smoker in the myocardial infarction group in respect to TIMI frame count, has suggested that smoking does not lead to further increase of TIMI frame counts. On the other hand, in patients without MI and with NCA, smokers have higher TIMI frame counts than non-smokers have.

[Tako-tsubo syndrome associated with a long course of the left anterior descending coronary artery along the apical diaphragmatic surface of the left ventricle]

INTRODUCTION AND OBJECTIVES

Tako-tsubo-like transient left ventricular apical ballooning has been described in Japan, but few cases have been reported in Western countries. We report one of the first series outside Japan, which provides new information on the coronary anatomy of this disorder.

PATIENTS AND METHODS

From January 1998 to February 2003 we observed 11 patients with a clinical suspicion of acute myocardial infarction, normal coronary arteries, and transient tako-tsubo-like systolic left ventricular apical ballooning. We compared the coronary artery anatomy in these 11 patients with that in 44 controls matched for age and sex: 22 with normal coronary arteries and 22 with acute myocardial infarction related with an obstructive thrombus in the left anterior descending coronary artery.

RESULTS

As in Japanese patients, tako-tsubo syndrome in Caucasian patients frequently occurs in women in their seventh or eighth decades of life, and is usually preceded by emotional or physical stress. The left anterior descending in our patients with tako-tsubo syndrome was longer overall, and its recurrent diaphragmatic segment was longer, than in controls. To compare these groups we designed a measure termed recurrent segment index (left anterior descending recurrent segment length/total left anterior descending length x 100). In tako-tsubo syndrome this index was 22.3 (1.5)%, vs 10.9 (6.7)% in normal controls (P<.001), and 11.3 (7.7)% in acute myocardial infarction patients (P<.001). Patients with acute myocardial infarction and a high recurrent segment index (> or =16%) had ventriculographic findings of systolic apical ballooning identical to those in patients with tako-tsubo syndrome.

CONCLUSIONS

All our patients with tako-tsubo syndrome had a left anterior descending with a long recurrent segment. The identical ventriculographic findings in patients with tako-tsubo syndrome and those with acute myocardial infarction with a long recurrent segment may be due to a common etiology.

Myocardial infarction resulting from nonatherosclerotic coronary artery diseases

Myocardial infarction (MI) infrequently results from nonatherosclerotic coronary diseases such as coronary embolism, spasm, dissection, and arteritis. If these disorders are not considered in the differential diagnosis of MI, specific beneficial therapies would be overlooked. Because physicians see large number of patients with MI during their career, the likelihood that they will encounter patients with MI resulting from nonatherosclerotic diseases is high. Two cases are presented to highlight different etiologies and treatment approaches of nonatherosclerotic MI.

High prevalence of (99m)tc-tetrofosmin reverse perfusion pattern in patients with myocardial infarction and angiographically smooth coronary arteries

BACKGROUND

There are no published data in the literature on the scintigraphic perfusion pattern in patients with myocardial infarction (MI) and normal coronary arteries (NCA).

OBJECTIVES

To evaluate myocardial perfusion imaging in a series of patients with MI and NCA.

METHODS

Twenty-seven patients who had developed a MI and had NCA were studied. As a control group we included 27 patients with a recent MI and coronary artery disease (CAD). All patients underwent stress/rest tetrofosmin myocardial perfusion SPECT within 6 months from MI.

RESULTS

In patients with NCA tetrofosmin stress images revealed 41 hypoperfused segments in 17 patients (63%). On rest images, 13 segments remained unchanged, 4 showed partial reperfusion, 10 normalized and 14 worsened. Additionally, there were 18 new hypoperfused segments in nine patients. Therefore, perfusion worsened at rest in 18 patients (67%) (32 segments). Overall, at rest there were 49 hypoperfused segments in 22 patients (81%). In patients with CAD, stress images revealed 71 hypoperfused segments. On rest images, 39 segments remained unchanged, 16 showed partial reperfusion and 12 normalized. Four segments worsened at rest and only four patients (15%) showed new perfusion defects at rest.

CONCLUSIONS

Myocardial perfusion with tetrofosmin might appear considerably worse at rest than at stress in patients with MI and NCA. Specifically, a reverse perfusion pattern in the infarct area is a frequent finding and is likely to be due to residual tissue viability. We postulate that in these patients the hyperemic response to exercise may mask resting underperfusion areas.

Myocardial infarction with normal coronary arteries: the pathologic and clinical perspectives

Myocardial infarction with normal coronary arteries is a syndrome resulting from numerous conditions but the exact cause in a majority of the patients remains unknown. Cigarette smokers and cocaine users are more prone to develop this condition. The possible mechanisms causing myocardial infarction with normal coronary arteries are hypercoagulable states, coronary embolism, an imbalance between oxygen demand and supply, intense sympathetic stimulation, non-atherosclerotic coronary diseases, coronary trauma, coronary vasospasm, coronary thrombosis, and endothelial dysfunction. It primarily affects younger individuals, and the clinical presentation is similar to that of myocardial infarction with coronary atherosclerosis. Thrombolytics, aspirin, nitrates, and beta blockers should be instituted as a standard therapy for acute myocardial infarction. Once normal coronary arteries are identified on subsequent angiography, the calcium channel blockers could be added since coronary vasospasm appears to play a major role in the pathophysiology of this condition. The beta blockers should be avoided in cocaine-induced myocardial infarction because the coronary spasm may worsen. In myocardial infarction with normal coronary arteries, complications such as malignant arrhythmia, heart failure, and hypotension are generally less common, and prognosis is usually good. Recurrent infarction, postinfarction angina, heart failure, and sudden cardiac death are rare. Stress electrocardiography and imaging studies are not useful prognostic tests and long-term survival mainly depends on the residual left ventricular function, which is usually good.

Myocarditis in patients with clinical presentation of myocardial infarction and normal coronary angiograms

OBJECTIVES

The aim of this study was to assess the diagnosis of myocarditis in patients presenting with acute myocardial infarction (MI) and normal coronary angiograms.

BACKGROUND

Most often in these patients, the etiologic diagnosis remains unclear once they are found to have normal coronary arteries. The diagnosis of myocarditis mimicking MI is clinically relevant, because numerous arguments suggest a relation between myocarditis and dilated cardiomyopathy. Myocardial indium-111 (111In)-antimyosin antibody (AMA)/rest thallium-201 (201Tl) imaging allows noninvasive detection of myocarditis.

METHODS

Forty-five patients admitted to three intensive care units for suspicion of acute MI, with normal coronary angiograms, were investigated. Indium-111-AMA planar images and then a dual-isotope rest AMA/201Tl tomographic study were performed. Six-month echocardiographic follow-up was obtained in 80% of the patients with initial left ventricular (LV) wall motion abnormalities.

RESULTS

In eight patients, AMA and 201Tl scintigraphy were negative. In two patients, a matched 201Tl defect and focal AMA uptake suggested acute MI (due to prolonged vasospasm or spontaneously reperfused coronary occlusion). In 17 patients, diffuse AMA uptake over the whole LV suggested diffuse myocarditis. In 18 patients, focal AMA uptake with a normal 201Tl scan suggested diffuse but heterogeneous, or focal myocarditis. Complete functional recovery was observed in 81% of the patients with a pattern of myocarditis.

CONCLUSIONS

Among 45 patients presenting with acute MI and normal coronary angiograms, 38% had diffuse myocarditis and 40% had a scintigraphic pattern of heterogeneous or focal myocarditis. Short-term follow-up showed complete LV functional recovery in 81% of these patients.

Occlusive vascular diseases in oral contraceptive users. Epidemiology, pathology and mechanisms

Despite being an unprecedented departure from normal physiology, the combined oral contraceptive is not only highly effective, but it also has a remarkably good safety record. Concerns over safety persist, though, particularly with regard to venous thromboembolism (VTE), stroke and myocardial infarction (MI). Epidemiological studies consistently show an increase in risk of VTE, but the results are more contentious with regard to arterial diseases. Despite 40 years of research, the mechanisms behind these adverse effects are not understood. In this review, we integrate information from published studies of the epidemiology and pathology of the occlusive vascular diseases and their risk factors to identify likely explanations for pathogenesis in oral contraceptive users. Oral contraceptives induce both prothrombotic and fibrinolytic changes in haemostatic factors and an imbalance in haemostasis is likely to be important in oral contraceptive-induced VTE. The complexity of the changes involved and the difficulty of ascribing clinical significance has meant that uncertainty persists. A seriously under-researched area concerns vascular changes in oral contraceptive users. Histologically, endothelial and intimal proliferation have been identified in women exposed to high plasma estrogen concentrations and these lesions are associated with thrombotic occlusion. Other structural changes may result in increased vascular permeability, loss of vascular tone and venous stasis. With regard to arterial disease risk, epidemiological information relating to dose effects and joint effects with other risk factors, and studies of pathology and changes in risk factors, suggests that oral contraceptive use per se does not cause arterial disease. It can, nevertheless, synergise very powerfully with subclinical endothelial damage to promote arterial occlusion. Accordingly, the prothrombotic effects of the oral contraceptive estrogen intervene in a cycle of endothelial damage and repair which would otherwise remain clinically silent or would ultimately progress - in, for example, the presence of cigarette smoking or hypertension - to atherosclerosis. Future work in this area should focus on modification of the effects of established risk factors by oral contraceptive use rather than modification of the supposed risk of oral contraceptive use by established risk factors. Attempts to understand vascular occlusion in oral contraceptive users in terms of the general features of VTE or with reference to atherosclerosis may be limiting, and future work needs to acknowledge that such occlusions may have unique features. Unequivocal identification of the mechanisms involved would contribute considerably to the alleviation of fears over vascular disease and to the development of even safer formulations.