The Journal of Tehran University Heart Center
Volume:2 Issue: 2, Apr 2007

Apical ballooning syndrome (ABS) is a reversible cardiomyopathy with presentation mimicking an acute coronary syndrome. So in clinical practice, it is essential to consider it in the differential diagnosis of patients presenting with chest pain, especially in postmenopausal women. Coronary angiography is usually indicated to achieve a proper diagnosis. Typically, patients do not have significant coronary artery lesions. Left ventriculography and echocardiography reveal a regional systolic dysfunction with akinesis of the midventricle, apex and compensatory hyperkinesis of the basal ventricular segments. Occurrence of an emotionally or physically stressful event is a feature of ABS but its absence does not exclude this diagnosis. Several pathophysiologic mechanisms had been proposed. The prognosis of ABS is good. In this review, we highlight the clinical manifestations, pathophysiology and management of this syndrome.

This study was designed to examine a unique and low dose use of intravenous enoxaparin in elective percutaneous coronary intervention (PCI) that would be applicable to an unselected population regardless of age, weight, and renal function. There is limited experience in anticoagulation using intravenous low-molecular-weight heparin in PCI. A total of 100 consecutive patients undergoing elective PCI were treated with a single IV bolus of enoxaparin (0.5mg/kg) in group A of patients (n=50) or with unfractionated heparin in group B of patients (n=50). Sheaths were removed immediately after the procedure in patients treated with enoxaparin and some hours later in those treated with unfractionated heparin. In group A, ACT was 124.6±9.3 before PCI and 149.2±17.1 after that (P<0.05). In group B, one patient (2.9%) developed groin hematoma. No deaths, MI, or urgent target vessel revascularization were reported. Low- dose (0.5 mg/kg) IV enoxaparin allows a target level of anticoagulation in patients undergoing PCI, appears to be safe and effective, allows immediate sheath removal, and does not require dose adjustment.

Stenting is currently the standard of care in percutaneous coronary intervention (PCI). Whether young patients remain at increased risk after PCI in the present stent era has not been investigated widely. We evaluated angiographic characteristics and short- and mid-term outcomes in patients younger than 40 years of age who underwent PCI. From April 2003 to March 2005, prospective data were collected in 118 consecutive patients, who were less than 40 years of age and underwent PCI at our referral center. The PCI outcomes in these patients were compared to those in 354 patients, randomly selected from 2493 patients older than 40 years of age in our database. Follow-up was scheduled at 1 month, 5 months, and 9 months through clinic visits, telephone interviews, and reviewing hospital records. Patients<40 years of age were more often male (91.5% vs. 71.8%, P<0.001), current smokers (33.9% vs. 15.2 %, P<0.001), and had more family history of coronary artery disease (38.1% vs. 21.8%, P<0.001) and myocardial infarction (44.1 vs. 31.1, p=0.01), while diabetes mellitus (6.8% vs. 22.1%, P<0.001), hypertension (13.6% vs. 35.3%, P<0.001), and hyperlipidemia (34.7% vs. 44.8%, P=0.055) were less common in these patients. There were no significant differences between the two groups regarding vessel involvement, reference vessel diameter, stenosis rate (before and after procedure), and lesion characteristics, with an exception that angulated lesions were more common in the patients≤ 40 years of age (P<0.05). The young patients, who underwent PCI, presented more frequently with single-vessel disease (61% vs. 46%, P=0.01).The vessel and lesion sites of PCI and clinical success rates were similar in these age groups. Usage of stent was high and similar, and drug- eluting stent use was not significantly different between the two groups. With a high procedural success (94.9% vs. 91.8%), intra-hospital and late complications were very low and similar in both groups. Percutaneous coronary intervention is a safe and effective procedure for young patients, and major adverse cardiac events are similar in young and older patients.

The hepatic secretion of apolipoprotein B (apoB), containing lipoproteins, is known to be regulated by insulin, and the overproduction of these atherogenic lipoproteins occurs in insulin-resistant states. Protein tyrosine phosphatase 1B (PTP-1B) is a key regulator of hepatic insulin signaling and is also upregulated in insulin resistance. We aimed to investigate the role of PTP-1B in regulating apoB mRNA translational efficiency mediated by 5''/3'' untranslated regions (UTRs) under conditions of insulin stimulation. Human hepatoma HepG2 cells were transfected with a vector carrying the firefly luciferase reporter gene and either a chimeric apoB mRNA encoding the 5''/3'' untranslated region (5''LUC3''-pGL3) or a null sequence of length equivalent to apoB 5'' UTR (LUC-pGL3). The transfected cells were then infected with adenovirus carrying the mouse PTP-1B gene (AdPTP1B) in the absence or presence of insulin, and the cellular luciferase activity was determined. The RNA extracts from cells were transfected with constructs carrying 5''/3'' apoB UTR, or a null sequence was also translated in vitro in a rabbit reticulocyte translation system. The luciferase activity of the cells transfected with constructs containing the apoB UTR sequences (5''LUC3'') was significantly higher than that of the control constructs carrying a null sequence (p<0.01, n=12). Similar results were observed following in vitro translation studies showing a significantly higher expression of the 5''/3'' UTR constructs (p<0.001, n=6). Treatment with 100 nM insulin led to a significant reduction in the luciferase activity of the constructs carrying apoB 5''/3'' UTR (p<0.0001, n=12). The down regulation of the apoB mRNA translation mediated by insulin was mediated by the apoB 5''/3'' UTR sequences since insulin did not affect the control constructs containing a null sequence. The infection of HepG2 cells expressing 5''LUC3'' or control constructs with AdPTP-1B attenuated the inhibitory effect of insulin and led to higher levels of luciferase activity compared to the Adb-gal infected control cells (p< 0.05, n=12). However, the activity was lower than that in the control cells infected with 5''LUC3''-pGL3 but not treated with insulin (p<0.05, n=12). Our data suggest that PTP-1B can potentially modulate apoB synthesis by blocking insulin-mediated inhibition of the apoB mRNA translation via its 5''/3'' UTR sequences. We hypothesize that the PTP-1B-mediated attenuation of the insulin action can lead to the upregulation of the apoB mRNA translation and contribute to a lipoprotein overproduction in conditions such as insulin resistance.

Age is one of the most important factors that have consistently emerged as the most potent predictors of mortality and morbidity after coronary artery bypass graft (CABG) surgery. However, early results of CABG in young patients in comparison with elderly ones have been different in previous surveys. The aim of this study was to compare short-term mortality and morbidity in young versus older patients and evaluate the presence of risk factors and their influence on outcome in both groups. We conducted a retrospective database review of 13222 patients divided into two age groups: patients less than 40 years old (411 patients) and those older (12811 patients), who underwent CABG at Tehran Heart Center between January 2002 and January 2007. We also compared preoperative, operative, and postoperative characteristics between them and assessed the influence of the variables on the length of stay in hospital (LOS) in the two groups. Among postoperative complications, only atrial fibrillation (P<0.001) was more prevalent in the elderly group and other complications were similar. The thirty-day mortality rate was higher in the elderly group (1.1% vs. 0%, P=0.023). Also, prolonged LOS (P<0.001) and ICU stay (P<0.001) were found more prevalent in the elderly group. Among the preoperative and postoperative variables, emergency surgery, diabetes mellitus, and previous myocardial infarction influenced the prolonged LOS in the young patients. Early mortality rate and prolonged length of stay in ICU and hospital were higher in the elderly than those in the young patients; however, other postoperative early complications were similar between the two groups.

Standard methods for the measurement of myocardial perfusion are invasive and require cardiac catheterization or the use of radioisotope dyes. The coronary sinus blood flow (CSBF) is an appropriate criterion for the efficacy of myocardial perfusion. This study sought to measure CSBF via transthoracic echocardiography (TTE) in patients with acute myocardial infarction (AMI) and to assess its relation with left ventricular ejection fraction (LVEF), wall motion scoring index (WMSI), and in-hospital mortality. This case-control study evaluated 20 patients (pts) with anterior AMI and 20 healthy individuals as controls over a 6-month period (in 2005) in Madani Heart Center in Tabriz (Iran). All the patients received the same drugs for AMI treatment (e.g. fibrinolytic). CSBF and WMSI, having been obtained via TTE, were compared between the two groups. Baseline variables were similar between the two groups (P>0.05). CSBF in the AMI group was 287.8±128 ml/min and in the control group was 415±127 ml/min (P=0.001). There was a significant correlation between CSBF and LVEF (r=0.52, P=0.01), between CSBF and WMSI (r=-0.77, P=0.0001), and between CSBF and in-hospital mortality (r=0.58, P=0.03). Our study demonstrated a good correlation between CSBF measured with 2D-doppler TTE and LVEF, WMSI, and in-hospital mortality.

Muscle fibers overlying the intramyocardial segment of an epicardial coronary artery are termed myocardial bridge (MB). The aim of this study was to analyze the mid-term outcome of MB and to examine its possible association with angiographic findings and concomitant cardiac pathologies such as hypertrophic cardiomyopathy (HCM). From a total of 3218 patients admitted for coronary angiography during 9 consecutive months, 28 (0.9%) were diagnosed with MBs with stenoses >=50%. Of these, 19 referred for follow-up with a median duration of 18 months. HCM was present in 5 patients (26.3%), of whom 4 had MB as the sole finding in angiography. Of the 19 patients, 14 had diastolic dysfunction. In follow-up, 2 patients were treated with revascularization strategies due to the concomitant coronary artery disease and in 2, syncope occurred. For two patients, an intra-cardiac device and a permanent pacemaker were implanted. Three patients with MB as the sole finding in angiography were readmitted because of chest pain. Diastolic dysfunction may contribute to the presentation of symptoms of muscle bridging. Also, myocardial bridging as the only finding in coronary angiography is highly associated with hypertrophic cardiomyopathy and may help to detect this group of patients. The mid-term outcome of myocardial bridges is favorable.

Myocardial free wall rupture is a catastrophic complication of acute myocardial infarction, and prognosis will depend on the prompt diagnosis by echocardiography, extension of infarct size, and prompt surgical treatment. Free wall rupture concomitant with ventricular septal defect (VSD) may be more complicated for management. A case of a 69-year-old man with myocardial free wall rupture and VSD following acute anterior myocardial infarction is presented.

The majority of coronary artery fistulas (CAFs) are congenital. The anomaly accounts for 0.4% of congenital heart defects and approximately 50% of pediatric coronary vasculature anomalies. Twenty percent of people with congenital CAFs have other concomitant cardiac anomalies, most frequently aortic and pulmonary atresia and patent ductus arteriosus. It is worthy of note that CAF with the tetralogy of Fallot has also been reported. Here we describe a patient with a double outlet right ventricle in association with a coronary artery fistula.

Mobile luminal mass of aortic arch is an unusual finding in patients with peripheral embolization. To search the source of these emboli, aortic arch mass should be considered. To our knowledge, transesophageal echocardiography (TEE) can be a useful modality to demonstrate the nature and exact location of the mass. This report is illustrative of a large mobile aortic arch mass, histologically thrombus, found by TEE in a 48- year-old woman with embolic symptoms.