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.

Functional anatomy of normal mitral valve-left ventricular complex by real-time, three-dimensional echocardiography.

BACKGROUND AND AIM OF THE STUDY: A detailed anatomic examination of the mitral valve (MV)-left ventricular (LV) complex (annulus, leaflets, chordae, papillary muscles, and ventricular wall) is needed for the accurate assessment of functional mitral regurgitation, and for planning patient-specific valve repair. In the past, normal values for the various components of the MV-LV complex have been derived from two-dimensional echocardiography (2DE), but such measurements require unconventional image planes and allow no off-line adjustments. In addition, measurement of the LV volumes and dimensions of irregular structures (mitral annulus) is more accurate by using three-dimensional echocardiography (3DE). The study aim was to assess, quantitatively, the MV-LV complex by real-time 3DE in normal adults. METHODS: The components of the MV-LV complex were measured off-line at mid-diastole (anterior MV leaflet), end-diastole and end-systole, after full volume real-time 3DE data sets had been obtained using a matrix transducer in 10 normal adults (six females, four males; mean age 25 +/- 5 years; range: 18-35 years; mean body surface area 1.8 +/- 0.2 m2). 2DE measurements were made for comparison. RESULTS: The 2DE measurements were systematically smaller (1-12%) than 3DE measurements, due to a foreshortening of the various components of the MV-LV complex during 2DE imaging. By 3DE imaging, MV competence in normal hearts was achieved by systolic reduction in the LV volume (58%), LV length (17%), inter-papillary muscle distance (39%), annular diameter (6% anteroposterior, 14% mediolateral), and the length of both papillary muscles (21-31%). At end-systole, the anterior MV leaflet was 20% shorter (2.5 +/- 0.3 versus 2.0 +/- 0.3 cm), due to folding at the coaptation point. CONCLUSION: These data provide normal real-time 3DE reference values for the MV-LV complex. 3DE appears superior to 2DE for accurate functional assessment of the MV-LV complex.

Assessment of right ventricular function by real-time three-dimensional echocardiography improves accuracy and decreases interobserver variability compared with conventional two-dimensional views.

AIMS: Two-dimensional echocardiographic (2DE) assessment of right ventricular (RV) function is difficult, often resulting in inconsistent RV evaluation. Real-time three-dimensional echocardiography (RT3DE) allows the RV to be viewed in multiple planes, which can potentially improve RV assessment and limit interobserver variability when compared with 2DE. METHODS AND RESULTS: Twenty-five patients underwent 2DE and RT3DE. Views of 2DE (RV inflow, RV short axis, and apical four-chamber) were compared with RT3DE views by four readers. RT3DE data sets were sliced from anterior-posterior (apical view) and from base to apex (short axis) to obtain six standardized planes. Readers recorded the RV ejection fraction (RVEF) from 2DE and RT3DE images. RVEF recorded by RT3DE (RVEF(3D)) and 2D (RVEF(2D)) were compared with RVEF by disc summation (RVEF(DS)), which was used as a reference. Interobserver variability among readers of RVEF(3D) and RVEF(2D) was then compared. Overall, mean RVEF(DS), RVEF(3D), and RVEF(2D) were 37 +/- 11%, 38 +/- 10%, 41 +/- 10%, respectively. The mean difference of RVEF(3D)-RVEF(DS) was significantly less than RVEF(2D)-RVEF(DS) (3.7 +/- 4% vs. 7.1 +/- 5%, P = 0.0066, F-test). RVEF(3D) correlated better with RVEF(DS) (r = 0.875 vs. r = 0.69, P = 0.028, t-test). RVEF(3D) was associated with a 39% decrease in interobserver variability when compared with RVEF(2D) [standard deviation of mean difference: 3.7 vs. 5.1, (RT3DE vs. 2DE), P = 0.018, t-test]. CONCLUSIONS: RT3DE provides improved accuracy of RV function assessment and decreases interobserver variability when compared with 2D views.

Clinical significance of epicardial fat measured using cardiac multislice computed tomography.

Cardiac adiposity defined as increased epicardial adipose tissue and massive deposits of fat within the atrial septum (lipomatous hypertrophy) is seen in overweight persons and is associated with coronary artery disease (CAD), atrial arrhythmias, and increased risk of left ventricular free wall rupture after acute myocardial infarction. Unlike subcutaneous fat, epicardial fat is metabollically active and produces hormones, cytokines, and other vasoactive substances that work systemically or locally to alter vascular endothelial function and may be implicated in the pathogenesis of CAD. The aim of the study was to assess the feasibility of measuring epicardial fat volume (EFV) and identify its clinical correlates using (64-slice) multislice computed tomography (MSCT). A protocol was devised to measure EFV using MSCT in 151 adults (age 26 to 83 years, mean 51 +/- 12; 55% men). Cross-sectional tomographic cardiac slices (2.5-mm thick) from base to apex (range 28 to 40 per heart) were traced semiautomatically using an off-line workstation, and EFV was measured by assigning Hounsfield units ranging from -30 to -250 to fat. Coronary computed tomographic angiography was performed using a standard protocol. EFV ranged from 25 to 274 ml (mean 121 +/- 47), corresponding to 2.4% to 30.5% (mean 15 +/- 5%) of total cardiac volume and correlated with age, atrial septum thickness, body weight, and body mass index. Coronary calcium score was significantly higher in patients with EFV >100 ml (67 +/- 155 vs 216 +/- 639; p = 0.03), and a higher percentage of patients with increased EFV had CAD (46% vs 31%; p <0.05) or metabolic syndrome (44% vs 29%; p <0.05). In conclusion, quantification of EFV was feasible using MSCT. Large deposits of fat around the heart and within the atrial septum were associated with obesity, coronary calcium, metabolic syndrome, and CAD. Measurement of EFV may provide another useful noninvasive indicator of heightened risk of CAD in addition to calcium score and coronary angiography.

Migration of a Central Venous Catheter in a Hemodialysis Patient Resulted in Left Atrial Perforation and Thrombus Formation Requiring Open Heart Surgery.

Central venous catheterization is widely used in patients on hemodialysis. A rare complication associated with the clinical use of central venous catheters is perforation of the heart or major vessels. We report a case of inadvertent perforation of the left atrium and thrombosis after the placement of a hemodialysis catheter in the right internal jugular vein. In such cases, surgical removal of the central venous catheter from perforation sites in the heart and vessel walls poses anesthetic challenges because of the high risk of pneumothorax, hemorrhage, arrhythmias, thrombosis, and death.

Effects of sprint training on contractility and [Ca(2+)](i) transients in adult rat myocytes.

The effects of 6-8 wk of high-intensity sprint training (HIST) on rat myocyte contractility and intracellular Ca(2+) concentration ([Ca(2+)](i)) transients were investigated. Compared with sedentary (Sed) myocytes, HIST induced a modest (5%) but significant (P < 0.0005) increase in cell length with no changes in cell width. In addition, the percentage of myosin heavy chain alpha-isoenzyme increased significantly (P < 0.02) from 0.566 +/- 0.077% in Sed rats to 0.871 +/- 0.006% in HIST rats. At all three (0.6, 1.8, and 5 mM) extracellular Ca(2+) concentrations ([Ca(2+)](o)) examined, maximal shortening amplitudes and maximal shortening velocities were significantly (P < 0.0001) lower and half-times of relaxation were significantly (P < 0.005) longer in HIST myocytes. HIST myocytes had significantly (P < 0.0001) higher diastolic [Ca(2+)](i) levels. Compared with Sed myocytes, systolic [Ca(2+)](i) levels in HIST myocytes were higher at 0.6 mM [Ca(2+)](o), similar at 1.8 mM [Ca(2+)](o), and lower at 5 mM [Ca(2+)](o). The amplitudes of [Ca(2+)](i) transients were significantly (P < 0.0001) lower in HIST myocytes. Half-times of [Ca(2+)](i) transient decline, an estimate of sarcoplasmic reticulum (SR) Ca(2+) uptake activity, were not different between Sed and HIST myocytes. Compared with Sed hearts, Western blots demonstrated a significant (P < 0.03) threefold decrease in Na(+)/Ca(2+) exchanger, but SR Ca(2+)-ATPase and calsequestrin protein levels were unchanged in HIST hearts. We conclude that HIST effected diminished myocyte contractile function and [Ca(2+)](i) transient amplitudes under the conditions studied. We speculate that downregulation of Na(+)/Ca(2+) exchanger may partly account for the decreased contractility in HIST myocytes.

Rescue of contractile abnormalities by Na+/Ca2+ exchanger overexpression in postinfarction rat myocytes.

Previous studies on myocytes isolated from rat hearts 3 wk after myocardial infarction (MI) demonstrated increased cell length, reduced Na(+)/Ca(2+) exchange (NCX1) activity, altered contractility, and intracellular Ca(2+) concentration ([Ca(2+)](i)) transients. In the present study, we investigated whether NCX1 overexpression in MI myocytes would restore contraction and [Ca(2+)](i) transients to normal. When myocytes were placed in culture under continued electrical-field stimulation conditions, differences in contraction amplitudes and cell lengths between sham and MI myocytes were preserved for at least 48 h. Infection of both sham and MI myocytes by adenovirus expressing green fluorescent protein resulted in >95% infection, as evidenced by green fluorescent protein fluorescence, but contraction amplitudes at 6-, 24-, and 48-h postinfection were not affected. NCX1 overexpression in MI myocytes resulted in lower diastolic [Ca(2+)](i) levels at all extracellular Ca(2+) concentrations ([Ca(2+)](o)) examined, suggesting enhanced forward NCX1 activity. At 5 mM [Ca(2+)](o), subnormal contraction and [Ca(2+)](i) transient amplitudes in MI myocytes (compared with sham myocytes) were restored toward normal levels by overexpressing NCX1. At 0.6 mM [Ca(2+)](o), supranormal contraction and [Ca(2+)](i) transient amplitudes in MI myocytes (compared with sham myocytes) were lowered by NCX1 overexpression. We conclude that overexpression of NCX1 in MI myocytes was effective in improving contractile dysfunction, most likely because of enhancement of both Ca(2+) efflux and influx during a cardiac cycle. We suggest that decreased NCX1 activity may play an important role in contractile abnormalities in postinfarction myocytes.

Impact of clinical predictors and routine coronary artery disease testing on outcome of patients admitted to chest pain decision unit.

BACKGROUND: Chest pain decision unit (CDU) evaluation of patients with acute chest pain (ACP) and nondiagnostic electrocardiogram (ECG) usually includes noninvasive testing for coronary artery disease (CAD). HYPOTHESIS: CAD evaluation will not improve clinical outcome in low-risk ACP patients. METHODS: We studied 459 adults admitted to CDU with ACP and no troponin release who underwent noninvasive CAD testing (stress testing in 396 and coronary computed tomographic angiography in 63). Multivariate logistic regression was used to determine predictors of adverse outcome over a 3-year follow-up period. RESULTS: Initial noninvasive test was normal in 367 (80%) and abnormal (positive or indeterminate) in 92 (20%). A total of 42 (9%) patients underwent invasive coronary angiography, and 16 (3.5%) underwent revascularization. During follow-up, 33 patients had a total of 36 major clinical events: 12 revascularizations, 9 myocardial infarctions, and 15 deaths. Multivariate logistic regression analysis identified abnormal ECG (odds ratio [OR]: 2.7, P = 0.03), typical chest pain (OR: 3.8, P = 0.002), diabetes (OR: 4.1, P = 0.001), and known CAD (OR: 2.3, P = 0.03) as independent predictors for adverse outcome, but not noninvasive test result. Thus, in 187 patients with no high-risk features (41% of the cohort), the annualized event rate was 0.5%. In 272 patients with at least 1 high-risk feature, annualized event rates were 2.8% and 5.7% when noninvasive test was normal or abnormal, respectively (P = 0.04). CONCLUSIONS: Clinical risk stratification allows identification of patients at low risk of adverse outcome over an intermediate period of follow-up. Noninvasive testing is not warranted in such patients.

'Mechanical thrombectomy alone' as a definite therapy for rescue angioplasty.

Coronary reperfusion strategies for acute ST segment elevation myocardial infarction (STEMI) include primary percutaneous coronary intervention (PCI), intravenous thrombolytic agents and recently mechanical thrombectomy alone during PCI, the latter reserved for those without significant residual disease post-thrombectomy. We describe the success of 'mechanical thrombectomy alone' in two young patients undergoing rescue angioplasty at our institution. Both patients were thrombolysed for inferior STEMI. During rescue PCI, post-thrombus aspiration, mild underlying atherosclerotic burden was detected in both patients, thus possibly obviating the need for further balloon angioplasty or stenting. Cost and compliance with long-term dual antiplatelet therapy (DAPT) was an additional factor to avoid stenting. Both patients received aspirin, clopidogrel, heparin and additional standard therapy for myocardial infarction (MI). Medication compliance was ensured by providing 1 month DAPT at no extra cost. Short-term follow-up at 1 and 3 months, for both patients was uneventful. Two-year, long-term follow-up, available for one patient has been uneventful.

Brugada syndrome with elevated cardiac biomarkers.

A 45-year-old man presented to our hospital with a history of palpitations, presyncope and chest pain. Vital signs and physical examination were unremarkable. Initial ECG  revealed sinus rhythm with non-specific ST changes. Subsequent ECGs showed rsr' in V1 and saddle-back pattern of ST elevation in lead V2, indicative of type 2 Brugada ECG pattern. Telemetry monitoring revealed multiple runs of asymptomatic non-sustained polymorphic ventricular tachycardia. Ajmaline challenge test confirmed the diagnosis of Brugada syndrome. The subsequent rise and fall of cardiac biomarkers was suggestive of acute myocardial infarction which was refuted by having normal coronaries by cardiac catheterisation. Echocardiogram showed normal cardiac structures and function without any evidence of myopericarditis. Automated intracardiac defibrillator was recommended which the patient declined.

Aneurysmal coronary cameral fistula.

A 26-year-old asymptomatic man, being medically managed for ventricular septal defect since childhood, presented to the outpatient clinic for a second opinion. Clinically, he was well built with normal vital signs. Cardiac auscultation was significant for a diastolic murmur over the praecordium. An ECG showed non-specific ST changes, and a subsequent transthoracic echocardiography performed revealed diastolic flow from the left ventricular (LV) anteroseptal wall into the LV cavity. A diagnosis of coronary-cameral fistula was confirmed by a multidetector CT which showed a 2.5×2 cm aneurysmal left anterior descending artery fistula to the LV. In addition to starting aspirin, transcatheter closure with occlusion device was considered knowing the potential risk of thrombus formation in the aneurysm and subsequent systemic embolisation. The patient however refused any percutaneous or surgical intervention. He remains asymptomatic 1 year after returning to his home country.

"Lone aspiration thrombectomy" without stenting in young patients with ST elevation myocardial infarction.

UNLABELLED: Plaque rupture with thrombotic occlusion without severe underlying coronary atherosclerosis is frequently observed during primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). These lesions are stented even if post thrombectomy mild underlying coronary artery disease (CAD) is noted. The value of mechanical thrombus aspiration alone "lone aspiration thrombectomy" (LAT) without stenting is not well studied. We present a retrospective analysis of patients receiving LAT as the only pPCI therapy for STEMI. Between January 2008 and March 2012, 202 young patients underwent pPCI for acute STEMI at our institution. From this group 10 patients had LAT as definitive therapy. LAT was favored if post thrombectomy minimal underlying CAD was noted, and concerns regarding long term treatment cost and compliance with dual antiplatelet therapy (DAPT) was an issue. All patients received ASA, clopidogrel, heparin and eptifibatide. DAPT was maintained for at least 1 month. One patient was lost to follow-up. At one month, all remaining 9 patients were free of MACE. At six weeks one patient had recurrent STEMI after abruptly discontinuing all his medications. Re-occlusion at the site of prior plaque rupture was stented, and treatment compliance was urged. Short term follow up at 2 months available for 5 patients and 2 years for 3 patients revealed no adverse consequences, the remaining patients had returned to their home countries. CONCLUSION: In selected young patients presenting with acute STEMI, LAT without balloon angioplasty or stenting is feasible and is associated with favorable short and long-term outcome.

Risk factor assessment of young patients with acute myocardial infarction.

UNLABELLED: The Middle East represents an attractive area for young individuals to seek employment, where they are exposed to numerous environmental conditions. The pursuit of a better standard of living has driven hundreds to the Middle East over the recent decades. This influx has also resulted in a predisposition to premature coronary artery disease (CAD). The aim of this study was to provide an overview of the risk factors in patients younger than 45 years, presenting with acute myocardial infarction (AMI). Out of the 148 patients analyzed, 137 were males and 11 females. 119 were from South Asia and 29 were Arabs. Their mean age was 36 ± 4.2 years. Smoking was the most prevalent risk factor in both groups at 67.6%. This was followed by hypertension, family history of CAD, hyperlipidemia and Diabetes mellitus. There was no significant difference in the clinical risk factor profile between these two groups. ST elevation myocardial infarction (STEMI) was noted in 67.6%, while 32.4% patients suffered a Non ST elevation myocardial infarction (NSTEMI). 84.5% received coronary stents, 8.8% had lone thrombus aspiration or balloon angioplasty only, while the rest were treated by conservative medical management or referred for coronary artery bypass surgery. CONCLUSION: There is no significant difference in the CAD risk profile between young South Asian and Arab patients. Preventive strategies focused on risk factor reduction, especially smoking cessation, should be implemented to protect young adults in the most productive years of their life.

Rare manifestation of Behcet's syndrome: insight from multimodality cardiovascular imaging.

A young Jordanian man was hospitalised with fever of 2 months duration. Preadmission diagnostic assessment including CT thorax and abdomen were inconclusive. Right-sided pleuritic chest pain was present on admission. Pulmonary embolism was suspected on a ventilation/perfusion lung scan. Lower-extremity deep venous thrombosis was, however, absent. Echocardiogram to exclude a cardiac source of pulmonary embolism showed a right ventricle mass which was also present on retrospective review of prehospitalisation CT thorax. Tissue characterisation of this mass on cardiac MRI was not helpful. Empiric anticoagulation was started without reduction in size at 3 weeks. Due to ongoing diagnostic uncertainty, surgical resection was performed. Histopathology confirmed this mass to be a thrombus. With unabated fever, right ventricular thrombosis with pulmonary embolism and cutaneous and scrotal ulceration which evolved later in the hospital course, a diagnosis of Bechet's syndrome was considered and subsequently confirmed. Response to immunosuppressive therapy was prompt.

Novel variant of dual left anterior descending coronary artery.

A 29-year-old African American man presented with atypical chest pain. Coronary computed tomographic angiography (64-slice) showed a previously not described variant of dual (duplicated) left anterior descending artery (LAD). Duplication of LAD is a rare anomaly and has been categorized into 4 angiographic subtypes based on the origin, course, and termination of the short and long LAD. Our case is unique in that, unlike previous subtypes, the short LAD originates independently from the left coronary sinus and that the long LAD arises from the right coronary sinus and has an intramyocardial course before reaching the distal interventricular groove. It can be, thus, considered a new variant of dual LAD (type V).