Non-ST-Elevation Myocardial Infarction-Like Syndrome in Scombroid Tuna Fish Poisoning

Mistreated fish products ingestion can lead to a histaminergic illness known as Scombroid Syndrome (SS). The disease usually causes cutaneous rash, stomach cramps, nausea, vomiting, breathing disorder and further histamine-related symptoms. To date, however, SS has been disregarded among the potential triggers of acute coronary syndrome (ACS), in spite of prior published occasional case reports. In the present study we describe 3 consecutive patients presenting with signs and symptoms of ACS associated to SS. Two men and a woman with no history of coronary artery disease and food allergy were studied. Clinical characteristics, electrocardiographic presentation and outcomes are described. Non-ST-elevation myocardial infarction-like pattern was observed in all patients. The 2 men underwent unremarkable coronary angiography, whereas the woman was just monitored at emergency department. All individuals had uneventful follow-up. The present study confirms non-ST-elevation myocardial infarction-like ACS as a possible histaminergic toxic, not allergic, epiphenomenon of mistreated raw tuna fish ingestion, likely due to transient epicardial and/or microvascular coronary vasospasm.

Very late recurrence of Takotsubo syndrome

Recurrence of the Takotsubo syndrome is possible, and in the majority of cases it occurs within 4 years. The present report is focused on a case of the Takotsubo syndrome recurrence after 10 years. The patient had been admitted for the first time in 1999 with a diagnosis of "non-q wave acute anterolateral myocardial infarction." Ten years later, she was readmitted for suspected acute myocardial infarction; coronary arteries, however, were normal, and the left ventricular angiogram demonstrated apical ballooning typical for the Takotsubo syndrome. It is worth noting that the clinical presentation and the ECG were the same on both occasions; in addition, both events were triggered by an emotional stress.

A rare case of lack of correlation of carotid atherosclerosis and coronary atherosclerosis

Signs of plaque inflammation in carotid arteries may serve as a window to the entire cardiovascular system, to identify "vulnerable" patients. Moreover, flow-mediated vasodilation in the brachial artery and intima media thickness (IMT) in the carotid artery could represent a surrogate diagnostic method for assessment of coronary artery disease (CAD) severity. Renal function is an important predictor of the presence and severity of angiographic CAD in patients without severe renal impairment with incremental value over traditional risk factors for CAD and IMT. It has also been reported ,that renal dysfunction may exert differential effects on the development of coronary and peripheral atherosclerosis. An accumulating burden of hypertension, diabetes, and smoking is important in the progression of atherosclerosis from the coronary to the carotid circulation. We present an unusual case of lack of correlation of carotid atherosclerosis and coronary atherosclerosis.

Quadricuspid morphology of the aortic valve

Quadricuspid aortic valve is a rare congenital heart defect. It may be isolated or associated to other cardiac anomalies. It may cause aortic valve dysfunction, commonly aortic regurgitation. Management of patients with quadricuspid aortic valve is represented by strict follow-up, because they may require aortic valve replacement in later life. We report the case of a 37-year old male patient, occasionally diagnosed to have quadricuspid aortic valve. Diagnosis and management are discussed.

Bifid T waves in leads V2 and V3 in children: a normal variant

Introduction

The T wave is rarely bifid, apart from patients with long QT syndrome or subjects treated with antiarrhythmic drugs. At times, a U wave partially superimposed upon the T wave is responsible for an apparently bifid T wave. Bifid T waves, in contrast, have been described in normal children in the past, but the phenomenon has not received any attention in recent years, to the extent that it is not mentioned in current textbooks of paediatric cardiology. Aim of the present study was to determine the incidence and clinical counterpart of bifid T waves in a paediatric population.

Methods

We selected 604 consecutive children free from clinically detectable heart disease; subjects whose electrocardiogram showed a bifid T wave underwent a complete clinical and echocardiographic examination. In addition, the electrocardiograms of 110 consecutive adults have also been analyzed. A T wave was considered as bifid whenever it was notched, being the 2 peaks separated from each other by a notch with duration ≥ 0.02 sec and voltage ≥ 0.05 mV. Moreover, in 7 children with bifid T wave in lead V2 further precordial recordings were obtained: a small electrode was gradually moved from V1 to V3, and 4 additional leads were recorded: 2 between V1 an V2, and 2 between V2 and V3.

Results

A bifid T wave was observed in 110 children (18,3%), with a relatively age-related incidence; the highest rate of bifid T waves (53%) occurred in the group of 5-year-old children. The bifid T wave was detected only in lead V2 in 51 cases (46,4%), only in lead V3 in 5 cases (4,6%), in both leads V2 and V3 in 50 cases (45,4%), and in leads other than V2 and V3 in 4 cases (3,6%). In the adult group, none of the examined electrocardiograms showed bifid T waves in any lead.

In the bifid T wave paediatric population, the echocardiogram did not reveal any abnormality, apart from 3 subjects which had an asymptomatic mitral valve prolapse; a trivial mitral and/or tricuspid regurgitation detected by color Doppler, as well as a patent foramen ovale in infants, were not considered as abnormal findings. The QTc interval was normal in all of the subjects; the average QTc interval was not different in the bifid T wave population (402 ± 46 msec) with respect to the control group (407 ± 39 msec).

Conclusion

The incidence of bifid T waves in leads V2 and V3 in normal children is high, and awareness of this phenomenon avoids possible misinterpretations leading to a diagnosis of ECG abnormalities.

Hyperventilation-induced ST segment elevation mimicking acute myocardial infarction in a comatose patient with tracheostomy

Controlled hyperventilation leading to respiratory alkalosis may induce coronary artery spasm. This manoeuvre is currently used in the diagnosis of Prinzmetal's angina. We describe the case of a comatose patient with tracheostomy in whom hyperventilation, caused by excessive bronchial secretion resulting in partial obstruction of the tracheal cannula, was followed by ST segment elevation mimicking acute myocardial infarction.

Alternating right and left bundle branch block aberration during atrial tachycardia

In a patient with atrial tachycardia with a rate of 200 per minute, the A-V conduction ratio was at times 2:1, but often it was 4:3 or 3:2 with progressive P-R interval prolongation (Wenckebach mechanism, an expression of presumable A-V nodal block). In each episode of 4:3 conduction, the first QRS complex was narrow, and the 2 ensuing beats were wide due to aberrant conduction. Aberration did not occur with a constant configuration, but in consecutive episodes of 4:3 conduction ratio there was a regular alternation of left bundle branch block and right bundle branch block. The pattern was explained by concealed retrograde conduction into the anterogradely blocked bundle branch. This caused 2 distinct effects: (1) shifting "to the right" of the refractory period of the affected bundle branch, resulting in maintenance of aberration with the same configuration, if consecutive atrial impulses were conducted to the ventricles, and (2) shortening of the effective cycle of the affected bundle branch, resulting in aberration due to block of the controlateral bundle branch, whenever a pause occasioned by a nonconducted atrial impulse was followed by restoration of 1:1 conduction for 2 or more consecutive beats.

Coronary artery embolisation

In the setting of an acute inferior myocardial infarction undergoing primary stent implantation, we could document a macroscopic embolus moving along the right coronary artery. Coronary embolisation is a well known drawback of percutaneous coronary interventions and dedicated devices can be used in order to minimize myocardial damage. Nonetheless, unexpected macroscopic embolisation after the first manual contrast injection through a diagnostic catheter remains a possible complication and may lead to unsatisfactory results when the upstream pharmacological therapy is not appropriate.

Can we finally get a coronary angiography with the least amount of dye?

The incidence of adverse events complicating coronary angiography is still considerably high. Founded concerns about risks of coronary angiography, and mainly its inherent invasiveness, have favored the increasing request for noninvasive techniques to evaluate the coronary anatomy, such as multislice computed tomography (MSCT). Nonetheless, it has to be kept in mind that several risks and complications are the same both for MSCT and conventional coronary angiography. Rotational angiography has been shown to be a powerful imaging tool for the evaluation of coronary anatomy resulting in the use of less contrast media and less radiation, without losing the possibility to obtain a precise, efficient and fast characterization of obstructive coronary artery disease. It is likely that in the next future the overall performance, taking into account both the diagnostic accuracy and the risk of exposure to radiation and contrast media, of MSCT techniques will have to be compared to that of rotational angiography, especially when the latter is coupled with minimally invasive approaches.

Left ventricular pseudodiverticulum

The differential diagnosis between left ventricular aneurysm and diverticulum remains a matter of debate. Cardiac magnetic resonance is dramatically helpful in the anatomical and functional characterization of the walls of any angiographical left ventricular outpouching.

Imaging of left main coronary artery dissection with multislice computed tomography

We occurred in a left main (LM) dissection during primary coronary intervention in a 45-year-old man with anterior acute myocardial infarction. Successful, multiple direct stenting was performed from the ostial to the mid left anterior descending coronary artery (LAD). Nonetheless, an LM dissection involving the proximal circumflex artery (Cx) was still evident at the end of the intervention. Multislice Computed Tomography (MSCT) coronary angiography images showed that LM dissection was definitely long and close to the ostium; moreover, the proximal stent had both excluded the false lumen in the LAD and stabilized the dissection towards the Cx. Two months later, at MSCT coronary angiography the LM dissection was still evident and the patient had remained totally asymptomatic. MSCT coronary angiography can be recommended as a complementary diagnostic tool for the assessment of LM anatomy because of the possibility of three-dimensional reconstructions and consequent clear evaluation of its take-off, course and bifurcation.

Acute myocardial infarction and rescue percutaneous transluminal coronary angioplasty in a young HIV-infected patient

We report a case of acute myocardial infarction in an HIV-infected patient without significant coronary artery disease (CAD) risk factors. The patient underwent rescue percutaneous transluminal coronary angioplasty (PTCA), with a successful outcome. We presume a possible pathogenetic role of anti-retroviral therapy and/or direct viral action on ischaemic heart disease progression. We propose that the current approach to management of AIDS-affected patients needs close monitoring for CAD risk factors and symptoms, to improve prognosis and life expectancy.

Myocardial ischemia due to a coronary-to-pulmonary artery fistula proximal to an intermediate stenosis in the left anterior descending coronary artery: percutaneous closure by means of angioplasty and stent grafting

This case report refers to a 46-year-old patient with symptomatic stable angina and myocardial ischemia documented at 99mTc-MIBI SPECT scintigraphy. Coronary angiography revealed a coronary artery fistula (CAF) and a non-significant stenosis of the left anterior descending coronary artery (LAD). We performed coronary angioplasty and stenting of the LAD and closure of the CAF using a covered stent. After the procedure the patient was asymptomatic and a myocardial scintigraphy, performed 6 months later, confirmed the absence of myocardial ischemia. This suggests that a CAF arising before a coronary stenosis may contribute to the genesis of myocardial ischemia, perhaps by giving rise to a steal phenomenon.

[Thrombo-embolic risk evaluation in patients with atrial fibrillation. Role of echocardiography]

Atrial fibrillation (AF) is the most common observed cardiac arrhythmia and is the most frequent condition associated with thromboembolic events in patients with or without mitral valve disease. The source of cardiac emboli is the left atrium, the left atrial appendage or, less frequently, the left ventricle. Emboli may also originate from aortic atherosclerotic plaques. It is important to identify patients at risk in order to perform the appropriate therapy. Risk stratification is multiparametric, being based on clinical, laboratory, and echocardiographic data. Several trials have pointed out the role of echocardiography in the evaluation of anatomic and functional parameters associated with thromboembolic risk. Transthoracic echocardiography (TTE) does not provide sufficient information regarding posterior cardiac structures, being its sensitivity in detecting thrombi relatively low (33-72%). Transesophageal echocardiography (TEE) in contrast, has an almost 100% sensitivity; this technique is, therefore, mandatory in patients with AF for an adequate prevention of thromboembolism. The echocardiographic information joined with clinical features allow to stratify, in a proper way, the risk of every single patient.

Anatomical M-mode: an old-new technique

The M-mode (motion mode) technique has improved the diagnostic possibilities of echocardiography due to its high temporal resolution. The use of a two-dimensional (2D) image as a basis for M-mode analysis at a defined line, independent of the transducer orientation, namely the anatomic M-mode (AMM), has been proposed from the beginning of 2D echocardiography. For several years, however, this could not be accomplished due to several reasons including the limited digital memory, the relatively rough pixels of 2D images, and the low temporal resolution of the screen. The AMM has been improved by the "fully digital" machines. These are able to provide a series of digital data (direction, position, and timing) relative to any single echo received from any point of the tissue. AMM analysis, thus, can be performed in any direction, as a "normal" monodimensional echocardiogram. With respect to traditional M-mode, AMM permits a more detailed analysis of cardiac chambers diameters obtained by linear measurements, regional wall motion of the left ventricle (both at rest and during stress), and location of accessory pathways. In particular, the assessment of left ventricular regional wall motion represents the most important goal of this new technique, which results in marked reduction or even elimination of the limitations due to the subjective character of wall motion evaluation with 2D echocardiography.

Sulfated polysaccharides inhibit leukocyte rolling in rabbit mesentery venules

Before firm adhesion, leukocytes roll slowly along the walls of small venules at velocities ranging from 0.7 to 36% of mean blood flow velocity. To investigate the nature of the adhesive process underlying leukocyte rolling, synthetic (dextran sulfate) and naturally occurring sulfated polysaccharides (heparin, chondroitin sulfates, keratan sulfate, and heparan sulfate) were infused via glass micropipettes into the lumen of small venules (20-60 microns diam) of the rabbit mesentery. Leukocyte rolling was observed and quantified using both transmitted light and incident fluorescence intravital microscopy. Rolling leukocytes accounted for 27-80% of total leukocyte flux, exhibiting a wide range of individual velocities (0.01-0.84 mm/s) with a mean value of 4% of centerline velocity. Dextran sulfate (Mr 500,000) inhibited leukocyte rolling very effectively [half-effective concentration (ED50) approximately 10 micrograms/ml] and was able to almost completely abolish rolling at 500 micrograms/ml. Heparin (ED50 approximately 50 micrograms/ml), chondroitin 6-sulfate C (ED50 approximately 500 micrograms/ml), and heparan sulfate (ED50 approximately 5 mg/ml) also reduced leukocyte rolling. At 5 mg/ml, chondroitin 4-sulfate B (dermatan sulfate) was marginally effective, but chondroitin 4-sulfate A and keratan sulfate were ineffective. The present data suggest that an adhesion receptor-ligand system distinct from the leukocyte integrins may be underlying transient leukocyte adhesion (rolling). Endothelial glycoproteins or proteoglycans containing sulfated side chains may be involved in mediating this adhesive process.