ISRN Cardiology

A Review of Most Relevant Complications of Transcatheter Aortic Valve Implantation

Siyamek Neragi-Miandoab and Robert E. Michler — Sun, 12 May 2013 10:04:16 +0000

Transcatheter aortic valve implantation (TAVI) has emerged for treating aortic stenosis in patients who are poor candidates for surgical aortic valve replacement. Currently, the balloon-expandable Edwards Sapien valve—which is usually implanted via a transfemoral or transapical approach—and the self-expanding CoreValve ReValving system—which is designed for retrograde application—are the most widely implanted valves worldwide. Although a promising approach for high-risk patients, the indication may be expanded to intermediate- and eventually low-risk patients in the future; however, doing so will require a better understanding of potential complications, risk factors for these complications, and strategies to individualize each patient to a different access route and a specific valve. This paper reviews the most relevant complications that may occur in patients who undergo catheter-based aortic valve implantation.

The Transaxial Orientation Is Superior to Both the Short Axis and Horizontal Long Axis Orientations for Determining Right Ventricular Volume and Ejection Fraction Using Simpson's Method with Cardiac Magnetic Resonance

Sun, 14 Apr 2013 18:55:05 +0000

We sought to determine which of the three orientations is the most reliable and accurate for quantifying right ventricular (RV) volume and ejection fraction (EF) by cardiac magnetic resonance using Simpson’s method. We studied 20 patients using short axis (SA), transaxial (TA), and horizontal long axis (HLA) orientations. Three readers independently traced RV endocardial contours at end-diastole and end-systole for each orientation. End-diastolic volumes (EDVs), end-systolic volumes (ESVs), and EF were calculated and compared with the 3D piecewise smooth subdivision surface (PSSS) method. The intraclass correlation coefficients among the 3 readers for EDV, ESV, and EF were 0.92, 0.82, and 0.42, respectively, for SA, 0.95, 0.92, and 0.67 for TA, and 0.85, 0.93, and 0.69 for HLA. For mean data there was no significant difference between TA and PSSS for EDV (−2.6%, 95% CI: −8.2 to 3.3%), ESV (−5.9%, −15.2 to 4.5%), and EF (1.7%, −1.5 to 4.9%). HLA was accurate for ESV (−8.9%, −18.5 to 1.8%) and EF (−0.7%, −3.8 to 2.5%) but significantly underestimated EDV (−9.8, −16.6 to −2.4%). SA was accurate for EDV (0.5%, −6.0 to 7.5%) but overestimated ESV (10.5%, 0.1 to 21.9%) and had poor interrater reliability for EF. Conclusions. The TA orientation provides the most reliable and accurate measures of EDV, ESV, and EF.

Elevated Cardiac Troponins in Setting of Systemic Inflammatory Response Syndrome, Sepsis, and Septic Shock

Nasir Hussain — Thu, 11 Apr 2013 12:00:09 +0000

Elevation of cardiac troponins and creatinine kinase is frequently observed in setting of systemic inflammatory response syndrome (SIRS), sepsis, or septic shock. Underlying pathophysiologic mechanism for such troponin leak, its clinical significance, and what different could be done in such settings remain elusive. In this paper we have briefly overviewed the proposed pathogenic mechanisms for SIRS, sepsis, or septic shock-related troponin elevation (SRTE) and have provided brief overview on its clinical significance. Upon review of the relevant literature we found that majority of patients with the SRTE with no prior history of coronary artery disease (CAD) upon testing are found not to have any CADs. We have also briefly discussed the possible pharmacologic agents and potential targets which are important from pathophysiologic and pharmacologic point of view that may alter the outcomes of SRTE-related myocardial depression in near future.

Dual Antiplatelet Therapy Can Be Discontinued at Three Months after Implantation of Zotarolimus-Eluting Stent in Patients with Coronary Artery Disease

Thu, 04 Apr 2013 17:52:48 +0000

Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention increases the risk of bleeding. We studied the safety and clinical outcomes of switching from DAPT to aspirin monotherapy at 3 months after ZES implantation. We retrospectively evaluated 168 consecutive patients with coronary artery disease who had been implanted with a ZES from June 2009 through March 2010. After excluding 40 patients according to exclusion criteria such as myocardial infarction, 128 patients were divided into a 3-month DAPT group (67 patients, 88 lesions) and a 12-month conventional DAPT group (61 patients, 81 lesions). Coronary angiographic followup and clinical followup were conducted at more than 8 months and at 12 months after ZES implantation, respectively. Minor and major bleeding events, stent thrombosis (ST), and major adverse cardiac events (MACE) (death, myocardial infarction, cerebrovascular accident, target lesion revascularization, and target vessel revascularization) were evaluated. There were no statistically significant differences in the incidences of ST and MACE between the two groups. The incidence of bleeding events was significantly lower in the 3-month group than in the 12-month group (1.5% versus 11.5%, ). DAPT can be safely discontinued at 3 months after ZES implantation, which reduces bleeding risk.

Hyperoxic Vasoconstriction of Human Pulmonary Arteries: A Novel Insight into Acute Ventricular Septal Defects

Sun, 31 Mar 2013 16:15:05 +0000

Objectives. Acute rises in pulmonary artery pressures following postinfarction ventricular septal defects present a challenge. We hypothesised that the abnormally high oxygen content exposure to the pulmonary arteries may be a factor. We investigated the contractile responses of human pulmonary arteries to changes in oxygen tension. Methods. Isometric tension was measured in large and medium sized pulmonary artery rings obtained from lung resections for patients with bronchial carcinoma (). Fresh rings were mounted in organ baths bubbled under basal conditions with hyperoxic or normoxic gas mixes and the gas tensions varied during the experiment. We studied whether voltage-gated calcium channels and nitric oxide signalling had any role in responses to oxygen changes. Results. Hypoxia caused a net mean relaxation of 18.1% 15.5 () from hyperoxia. Subsequent hyperoxia caused a contraction of 19.2% 13.5 (). Arteries maintained in normoxia responded to hyperoxia with a mean constriction of 14.8% 3.9 (). Nifedipine inhibited the vasoconstrictive response () whilst L-NAME had no effect on any hypoxic vasodilatory response. Conclusions. We demonstrate that hyperoxia leads to vasoconstriction in human pulmonary arteries. The mechanism appears to be dependent on voltage-gated calcium channels. Hyperoxic vasoconstriction may contribute to acute rises in pulmonary artery pressures.

Intracoronary Adenosine versus Intravenous Adenosine during Primary PCI for ST-Elevation Myocardial Infarction: Which One Offers Better Outcomes in terms of Microvascular Obstruction?

Gemina Doolub and Erica Dall'Armellina — Wed, 27 Mar 2013 17:32:56 +0000

Aims. Previous studies have suggested that intravenous administration of adenosine improves myocardial reperfusion and reduces infarct size in ST-elevation myocardial infarction (STEMI) patients. Intracoronary administration of adenosine has shown conflicting results. Methods. In this retrospective, single-centre, blinded clinical study, we assessed whether selective intracoronary administration of adenosine distal to the occlusion site immediately before initial balloon inflation reduces microvascular obstruction (MVO) as assessed with cardiac magnetic resonance imaging (MRI). Using contrast-enhanced sequences, microvascular obstruction (MVO) was calculated. We found 81 patients presenting with STEMI within 12 h from symptom onset who were eligible for the study. In 80/81 (100%) patients receiving the study drug, MRI was performed on Day 1 after primary angioplasty. Results. The prevalence of MVO was reduced in the patients treated with intracoronary adenosine, (45%) compared to 85% of patients who were administered intravenous adenosine (). We found that the size of MVO in patients receiving intracoronary adenosine was significantly reduced compared to 0.91 g in the intravenous-treated group (). There was no statistically significant difference in TIMI flow and clinical outcomes after primary PCI. Conclusion. We found significant evidence that selective high-dose intracoronary administration of adenosine distal to the occlusion site of the culprit lesion in STEMI patients results in a decrease in microvascular obstruction.

Amiodarone-Induced Cirrhosis of Liver: What Predicts Mortality?

Nasir Hussain, Anirban Bhattacharyya, and Suartcha Prueksaritanond — Thu, 14 Mar 2013 19:18:17 +0000

Introduction. Amiodarone has been used for more than 5 decades for the treatment of various tachyarrhythmias and previously for the treatment of refractory angina. There are multiple well-established side effects of amiodarone. However, amiodarone-induced cirrhosis (AIC) of liver is an underrecognized complication. Methods. A systematic search of Medline from January 1970 to November 2012 by using the following terms, amiodarone and cirrhosis, identified 37 reported cases of which 30 were used in this analysis. Patients were divided into 2 subsets, survivors versus nonsurvivors, at 5 months. Results. Aspartate aminotransferase was significantly lower () in patients who survived at 5-months (mean 103.33 IU/L) compared to nonsurvivors (mean 216.88 IU/L). There was no statistical difference in the levels of prothrombin time, total bilirubin, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase, cumulative dose, and latency period between the two groups. The prevalence of DM, HTN, HLD, CAD, and CHF was similar in the two groups. None of the above-mentioned variables could be identified as a predictor of survival at 5 months. Conclusion. AIC carries a mortality risk of 60% at 5 months once the diagnosis is established. Further prospective studies are needed to identify predictors of AIC and of mortality or survival in cases of AIC.

Diagnosis and Treatment of Asymptomatic Left Ventricular Systolic Dysfunction after Myocardial Infarction

Tue, 12 Mar 2013 08:57:58 +0000

The increased survival after acute myocardial infarction induced an increase in heart failure with left ventricular systolic dysfunction. Early detection and treatment of asymptomatic left ventricular systolic dysfunction give the chance to improve outcomes and to reduce costs due to the management of patients with overt heart failure.

QRS Complex Enlargement as a Predictor of Ventricular Arrhythmias in Patients Affected by Surgically Treated Tetralogy of Fallot: A Comprehensive Literature Review and Historical Overview

Pier Paolo Bassareo and Giuseppe Mercuro — Wed, 20 Feb 2013 08:27:24 +0000

Tetralogy of Fallot (TOF) is a congenital heart disease frequently treated by surgical repair to relieve symptoms and improve survival. However, despite the performing of an optimal surgical repair, TOF patients are at times characterized by a poor long-term survival rate, likely due to cardiac causes such as ventricular arrhythmias, with subsequent sudden death. In the 80s it was irrefutably demonstrated that QRS prolongation ≥180 msec at basal electrocardiogram is a strong predictor for refining risk stratification for ventricular tachycardia in these patients. The aim of this research was to undertake a review of all studies conducted to assess the impact of QRS duration on the development of life-threatening ventricular arrhythmias in repaired TOF subjects.

Pathobiology of Obstructive Sleep Apnea-Related Dyslipidemia: Focus on the Liver

Aibek E. Mirrakhimov and Alaa M. Ali — Wed, 02 Jan 2013 09:52:06 +0000

Obstructive sleep apnea and dyslipidemia are common medical disorders that independently increase vascular morbidity and mortality. Current animal and human data show that, indeed, obstructive sleep apnea may mediate pathological alterations in cholesterol and triglyceride metabolism. The mechanisms involved are increased lipolysis, decreased lipoprotein clearance, and enhanced lipid output from the liver. Human evidence shows that the treatment of obstructive sleep apnea with continuous positive airway pressure leads to an improvement of postprandial hyperlipidemia. However, more studies are needed, to clarify the pathophysiology of the interrelationship between obstructive sleep apnea and dyslipidemia and whether treatment of obstructive sleep apnea will lead to an improvement in the lipid profile and, more importantly, reduce hyperlipidemia-related vascular outcomes.

Changes in Lipids and Lipoprotein Indices in Relation to the Severity of Hypertension in Newly Diagnosed Hypertensive Nigerians

E. I. Onwubuya, B. C. Anisiuba, C. U. Osuji, and J. E. Ahaneku — Tue, 11 Dec 2012 15:52:50 +0000

Hypertension and dyslipidaemia are important components of metabolic syndrome and both are known to complicate each other. Materials and Methods. A total of 149 subjects consisting of 107 hypertensive patients, grouped into 3 (of 37, 35, and 35 patients categorized based on the grade of hypertension as grade 1, grade 2, and grade 3, resp.) and 42 controls, were recruited for this study. Each subject had a recording of the bio- and anthropometric data comprising of the age, height, weight, body mass index (BMI), and abdominal circumference (AC). The blood pressure was also recorded. Fasting blood was collected and serum was used for the estimation of the lipids: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG), while low density lipoprotein cholesterol (LDL-C) and VLDL were estimated using Friedewald formula. Findings. Patients with hypertension had higher lipid and lipoprotein levels than the controls and the values became more significant with increasing severity of hypertension. The difference was statistically significant for TC, LDL-C, and VLDL-C (). Conclusion. This study showed that lipid and lipoprotein cholesterol abnormalities exist and even worsen with severity of hypertension. It is important that investigations in patients with hypertension should include a lipid profile.

Cardiac Ion Channelopathies and the Sudden Infant Death Syndrome

Ronald Wilders — Wed, 05 Dec 2012 14:34:54 +0000

The sudden infant death syndrome (SIDS) causes the sudden death of an apparently healthy infant, which remains unexplained despite a thorough investigation, including the performance of a complete autopsy. The triple risk model for the pathogenesis of SIDS points to the coincidence of a vulnerable infant, a critical developmental period, and an exogenous stressor. Primary electrical diseases of the heart, which may cause lethal arrhythmias as a result of dysfunctioning cardiac ion channels (“cardiac ion channelopathies”) and are not detectable during a standard postmortem examination, may create the vulnerable infant and thus contribute to SIDS. Evidence comes from clinical correlations between the long QT syndrome and SIDS as well as genetic analyses in cohorts of SIDS victims (“molecular autopsy”), which have revealed a large number of mutations in ion channel-related genes linked to inheritable arrhythmogenic syndromes, in particular the long QT syndrome, the short QT syndrome, the Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia. Combining data from population-based cohort studies, it can be concluded that at least one out of five SIDS victims carries a mutation in a cardiac ion channel-related gene and that the majority of these mutations are of a known malignant phenotype.

Depression and Coronary Heart Disease

Karina W. Davidson — Thu, 22 Nov 2012 09:18:18 +0000

There are exciting findings in the field of depression and coronary heart disease. Whether diagnosed or simply self-reported, depression continues to mark very high risk for a recurrent acute coronary syndrome or for death in patients with coronary heart disease. Many intriguing mechanisms have been posited to be implicated in the association between depression and heart disease, and randomized controlled trials of depression treatment are beginning to delineate the types of depression management strategies that may benefit the many coronary heart disease patients with depression.

Computational Cardiology: The Heart of the Matter

Natalia A. Trayanova — Wed, 14 Nov 2012 14:23:43 +0000

This paper reviews the newest developments in computational cardiology. It focuses on the contribution of cardiac modeling to the development of new therapies as well as the advancement of existing ones for cardiac arrhythmias and pump dysfunction. Reviewed are cardiac modeling efforts aimed at advancing and optimizing existent therapies for cardiac disease (defibrillation, ablation of ventricular tachycardia, and cardiac resynchronization therapy) and at suggesting novel treatments, including novel molecular targets, as well as efforts to use cardiac models in stratification of patients likely to benefit from a given therapy, and the use of models in diagnostic procedures.

Carotid Artery Disease and Stroke: Assessing Risk with Vessel Wall MRI

William S. Kerwin — Wed, 14 Nov 2012 09:50:58 +0000

Although MRI is widely used to diagnose stenotic carotid arteries, it also detects characteristics of the atherosclerotic plaque itself, including its size, composition, and activity. These features are emerging as additional risk factors for stroke that can be feasibly acquired clinically. This paper summarizes the state of evidence for a clinical role for MRI of carotid atherosclerosis.

Glycemic Control during Coronary Artery Bypass Graft Surgery

Harold L. Lazar — Wed, 14 Nov 2012 09:37:38 +0000

Hyperglycemia, which occurs in the perioperative period during cardiac surgery, has been shown to be associated with increased morbidity and mortality. The management of perioperative hyperglycemia during coronary artery bypass graft surgery and all cardiac surgical procedures has been the focus of intensive study in recent years. This report will paper the pathophysiology responsible for the detrimental effects of perioperative hyperglycemia during cardiac surgery, show how continuous insulin infusions in the perioperative period have improved outcomes, and discuss the results of trials designed to determine what level of a glycemic control is necessary to achieve optimal clinical outcomes.

Left Ventricular Hypertrophy Is Associated with Diastolic Filling Alterations in Normotensive Offspring of Hypertensive Nigerians

P. M. Kolo, E. O. Sanya, A. B. Omotoso, A. Soladoye, and J. A. Ogunmodede — Tue, 30 Oct 2012 14:58:53 +0000

Contribution of left ventricular diastolic dysfunction to adverse events in patients with cardiovascular diseases is increasingly being recognized and individuals with pedigree for hypertension are thought to exhibit anatomic and or functional changes in their left ventricle before they become hypertensive. This study aimed at characterizing left ventricular diastolic function in normotensive offspring of hypertensive Nigerians. Sixty-five offspring of hypertensive parents aged 15–25 years (subjects) with 65-age and sex-matched offspring of normotensive parents (controls) were studied for early makers of hypertensive cardiovascular disease using Doppler echocardiogram. Mean mitral E velocity was reduced () in the subjects ( cm/s) compared with the controls ( cm/s). Similarly, mean S velocity of pulmonary venous flow was lower () in the subjects than in the controls. Left atrial dimension and mitral E/A ratio in the subjects with left ventricular hypertrophy were higher (, 0.004 respectively) than in the subjects without this abnormality. We concluded that normotensive offspring of hypertensive Nigerians showed early alterations in indexes of left ventricular diastolic filling and these abnormalities were exaggerated in the presence of left ventricular hypertrophy.

Physical Activity, Health Benefits, and Mortality Risk

Peter Kokkinos — Tue, 30 Oct 2012 07:41:37 +0000

A plethora of epidemiologic evidence from large studies supports unequivocally an inverse, independent, and graded association between volume of physical activity, health, and cardiovascular and overall mortality. This association is evident in apparently healthy individuals, patients with hypertension, type 2 diabetes mellitus, and cardiovascular disease, regardless of body weight. Moreover, the degree of risk associated with physical inactivity is similar to, and in some cases even stronger than, the more traditional cardiovascular risk factors. The exercise-induced health benefits are in part related to favorable modulations of cardiovascular risk factors observed by increased physical activity or structured exercise programs. Although the independent contribution of the exercise components, intensity, duration, and frequency to the reduction of mortality risk is not clear, it is well accepted that an exercise volume threshold defined at caloric expenditure of approximately 1,000 Kcal per week appears to be necessary for significant reduction in mortality risk. Further reductions in risk are observed with higher volumes of energy expenditure. Physical exertion is also associated with a relatively low and transient increase in risk for cardiac events. This risk is significantly higher for older and sedentary individuals. Therefore, such individuals should consult their physician prior to engaging in exercise.

Insights into the Pathogenesis of Takotsubo Syndrome, Which with Persuasive Reasons Should Be Regarded as an Acute Cardiac Sympathetic Disease Entity

Shams Y-Hassan — Mon, 15 Oct 2012 08:39:02 +0000

The pathogenesis of takotsubo syndrome (TS) has not been established yet. The literature data dealing with the pathogenesis of TS are abundant but scattered among different medical specialities. Subarachnoid hemorrhage and other acute intracranial diseases and injuries are among the important and currently well-recognized trigger factors for TS. In both induced and spontaneous subarachnoid hemorrhages, signs suggestive of increased cardiac sympathetic overactivity have been documented. Surgical and pharmacological sympathectomy has shown to have protective cardiac effects in both animal and human studies. Increase in local release of norepinephrine from the heart of patients with TS has been measured. Signs of both cardiac sympathetic denervation and myocardial lesions adjacent to the cardiac nerve terminals have been seen. Furthermore, the systematized and typically circumferential pattern of ventricular wall motion abnormality is incongruent with the coronary artery supply region and appears most likely to follow the cardiac sympathetic nerve distribution. In conclusion, compelling literature data support the hypothesis that acute cardiac sympathetic disruption and norepinephrine seethe and spillover is causing TS in predisposed patients. TS is most probably an acute cardiac sympathetic disease entity causing myocardial stunning in which takotsubo is one among other cardiac image study findings.

Clinical Evaluation of a Mobile Heart Rhythm Telemonitoring System

Hristo Mateev, Iana Simova, Tzvetana Katova, and Nikolay Dimitrov — Sun, 14 Oct 2012 15:04:05 +0000

Purpose. To evaluate the clinical applicability of a telemonitoring system: telemetric system for collection and distant surveillance of medical information (TEMEO). Methods. We evaluated 60 patients, applying simultaneously standard Holter ECG and telemonitoring. Two different comparisons were performed: (1) TEMEO ECG with standard 12-lead ECG; (2) TEMEO Holter with standard ECG Holter. Results. We found a very high coincidence rate (99.3%) between TEMEO derived ECGs and standard ECGs. Intraclass correlation coefficient analysis revealed high and significant correlation coefficients regarding average, maximal, and minimal heart rate, % of time in tachycardia, single supraventricular ectopic beats (SVEB), and single and couplets of ventricular ectopic beats (VEB) between Holter ECG and TEMEO derived parameters. Couplets of SVEB were recorded as different by the two monitoring systems, however, with a borderline statistical significance. Conclusions. TEMEO derived ECGs have a very high coincidence rate with standard ECGs. TEMEO patient monitoring provides results that are similar to those derived from a standard Holter ECG.

The Sweet Spot: Continued Search for the Glycemic Threshold for Macrovascular Disease—A Retrospective Single Center Experience

Sun, 14 Oct 2012 15:03:14 +0000

Background. Atherosclerotic cardiovascular disease (ASCVD) is a common complication of diabetes mellitus and impaired fasting glucose (IFG). We hypothesized that the relation of fasting glucose levels to ASCVD is linear, with the prevalence of clinical ASCVD beginning to increase even among individuals currently categorized as normoglycemic. Methods. Patient charts were retrospectively reviewed from our Dyslipidemic Preventive Cardiology Clinic. We evaluated the prevalence of ASCVD relative to fasting glucose levels in a cross-section of patients at high risk for ASCVD. Results. In 558 dyslipidemic patients, ASCVD prevalence increased with increasing fasting glucose levels. A significantly higher prevalence of ASCVD was observed among patients with fasting glucose levels between 90 and 99 mg/dL versus lower levels. As glucose levels increased from 90 to 125 mg/dL, the prevalence of ASCVD continued to rise in parallel. Logistic regression analysis with forward likelihood ratio stepwise selection indicated that individuals with fasting blood glucose of 90–99 mg/dL were 2.6 times more likely to have ASCVD than those with lower levels of fasting blood glucose. Conclusion. Our findings suggest that the current cutoff for impaired fasting glucose of 100 mg/dL may be somewhat conservative and that a level above 90 mg/dL may be more appropriate as an ASCVD risk factor, particularly in patients with a lipid disorder.

Persistent Atrial Fibrillation Is Associated with Worse Prognosis Than Paroxysmal Atrial Fibrillation in Acute Cerebral Infarction

Halvor Naess, Ulrike Waje-Andreassen, and Lars Thomassen — Thu, 27 Sep 2012 08:57:06 +0000

Background and Purpose. We hypothesized that patients with persistent atrial fibrillation (AF) suffer from more severe cerebral infarction than patients with paroxysmal AF due to differences in clot structure and volume. Methods. This study includes consecutive patients with acute cerebral infarction and persistent or paroxysmal AF documented by ECG any time prior to stroke onset. The National Institute of Health Stroke Scale (NIHSS) was used to assess stroke severity on admission. Short-term outcome was determined by the modified Rankin scale (mRS) score, Barthel index, and NIHSS score 7 days after stroke onset. Risk factors were registered on admission. Eligible patients were treated with thrombolysis. Results. In total, 141 (52%) patients had paroxysmal AF, and 129 (48%) patients had persistent AF. NIHSS score on admission, mRS score at day 7, and mortality were significantly higher among patients with persistent AF. Thrombolysis was less effective in patients with persistent AF. Conclusions. Our study shows that patients with persistent AF and acute cerebral infarction have poorer short-term outcome than patients with paroxysmal AF. Differences in clot structure or clot volume may explain this.

MMP-2 and sTNF-R1 Variability in Patients with Essential Hypertension: 1-Year Follow-Up Study

Thu, 13 Sep 2012 17:50:45 +0000

The aim of this study is to analyze MMP-2 and sTNF-R1 variability, potent predictors of cardiovascular events, in stable hypertensive patients during a 12-month followup. 234 asymptomatic patients (age 60±13, 136 male) out of 252 patients with essential hypertension were followed up. MMP-2 and sTNF-R1 were measured at baseline and after 12 months (stage I). To compare MMP-2 and sTNF-R1 levels over time interval, we used the statistical method of Bland-Altman. MMP-2 and sTNF-R1 reproducibility was good in our patients for the two intervals with a coefficient of reproducibility of 8.2% and 11.3%, respectively. The percentages of patients within 1.96 × standard deviation of the mean were 93.6% and 92.7%. An elevated coefficient of correlation was obtained for MMP-2, basal versus stage I (𝑟=0.55, 𝑃<0.0001) and for sTNF-R1 (𝑟=0.75, 𝑃<0.0001). There is good stability in MMP-2 and sTNF-R1 levels in a followup study of patients with stable hypertension. As a consequence, assessment of its concentrations may be a useful tool for monitoring the follow-up of these patients. Measured variations in MMP-2 and sTNF-R1 levels, exceeding 8.2% and 11.3%, respectively, may indicate an increase in cardiovascular risk, thus, could be used to optimizing treatment than blood pressure control alone.

CT Imaging of Coronary Stents: Past, Present, and Future

Andreas H. Mahnken — Tue, 11 Sep 2012 08:29:02 +0000

Coronary stenting became a mainstay in coronary revascularization therapy. Despite tremendous advances in therapy, in-stent restenosis (ISR) remains a key problem after coronary stenting. Coronary CT angiography evolved as a valuable tool in the diagnostic workup of patients after coronary revascularization therapy. It has a negative predictive value in the range of 98% for ruling out significant ISR. As CT imaging of coronary stents depends on patient and stent characteristics, patient selection is crucial for success. Ideal candidates have stents with a diameter of 3 mm and more. Nevertheless, even with most recent CT scanners, about 8% of stents are not accessible mostly due to blooming or motion artifacts. While the diagnosis of ISR is currently based on the visual assessment of the stent lumen, functional information on the hemodynamic significance of in-stent stenosis became available with the most recent generation of dual source CT scanners. This paper provides a comprehensive overview on previous developments, current techniques, and clinical evidence for cardiac CT in patients with coronary artery stents.

Recurrent Syncope in Patients with Carotid Sinus Hypersensitivity

Alfonso Lagi, Sergio Cerisano, and Simone Cencetti — Mon, 10 Sep 2012 09:50:48 +0000

Syncope recurrence in pacemaker-implanted subjects for the cardio-inhibitory response to sinus carotid massage (SCM) was investigated. The study-hypothesis was that recurrences had significant vasodepressor responses that could justify the loss of consciousness. Forty-six patients were enrolled (16 patients and 30 controls), followed and revaluated after 5–7 years. At the end of follow-up, significant differences were found between patients and controls in mean SCM SAP (87 versus 106 mmHg) and reduction in mean SCM SAP (59 versus 38 mmHg); in the number of symptomatic subjects soon after SCM (5 versus 1); and in the number of subjects suffering from orthostatic hypotension. A subgroup of 13 patients showed significantly different hypotensive responses to SCM compared with the values observed at study recruitment. The data showed that some subjects with a defined hemodynamic pattern in response to SCM may change their characteristics and have spontaneous and/or provocative symptoms. These data explain the syncopal relapses, and suggest the presence of autonomic dysregulation in individuals with carotid sinus hypersensitivity.

Radiation Dose Reduction during Radial Cardiac Catheterization: Evaluation of a Dedicated Radial Angiography Absorption Shielding Drape

Tue, 04 Sep 2012 15:03:20 +0000

Objectives. Radiation scatter protection shield drapes have been designed with the goal of decreasing radiation dose to the operators during transfemoral catheterization. We sought to investigate the impact on operator radiation exposure of various shielding drapes specifically designed for the radial approach. Background. Radial access for cardiac catheterization has increased due to improved patient comfort and decreased bleeding complications. There are concerns for increased radiation exposure to patients and operators. Methods. Radiation doses to a simulated operator were measured with a RadCal Dosimeter in the cardiac catheterization laboratory. The mock patient was a 97.5 kg fission product phantom. Three lead-free drape designs were studied. The drapes were placed just proximal to the right wrist and extended medially to phantom’s trunk. Simulated diagnostic coronary angiography included 6 minutes of fluoroscopy time and 32 seconds of cineangiography time at 4 standard angulated views (8 s each), both 15 frames/s. ANOVA with Bonferroni correction was used for statistical analysis. Results. All drape designs led to substantial reductions in operator radiation exposure compared to control (𝑃<0.0001). The greatest decrease in radiation exposure (72%) was with the L-shaped design. Conclusions. Dedicated radial shielding drapes decrease radiation exposure to the operator by up to 72% during simulated cardiac catheterization.

Doxorubicin and NRG-1/erbB4-Deficiency Affect Gene Expression Profile: Involving Protein Homeostasis in Mouse

Wed, 29 Aug 2012 14:53:29 +0000

The accumulating evidence demonstrates the essential role of neuregulin-1 signaling in the adult heart, and, moreover, indicates that an impaired neuregulin signaling exacerbates the doxorubicin-mediated cardiac toxicity. Despite this strong data, the specific cardiomyocyte targets of the active erbB2/erbB4 heterodimer remain unknown. In this paper, we examined pathways involved in cardiomyocyte damage as a result of the cardiac sensitization to anthracycline toxicity in the ventricular muscle-specific erbB4 knockout mouse. We performed morphological analyses to evaluate the ventricular remodeling and employed a cDNA microarray to assess the characteristic gene expression profile, verified data by real-time RT-PCR, and then grouped into functional categories and pathways. We confirm the upregulation of genes related to the classical signature of a hypertrophic response, implicating an erbB2-dependent mechanism in doxorubicin-treated erbB4-KO hearts. Our results indicate the remarkable downregulation of IGF-I/PI-3′ kinase pathway and extends our current knowledge by uncovering an altered ubiquitin-proteasome system leading to cardiomyocyte autophagic vacuolization.

A Method for Ventricular Late Potentials Detection Using Time-Frequency Representation and Wavelet Denoising

Matteo Gadaleta and Agostino Giorgio — Sun, 26 Aug 2012 10:23:02 +0000

This study proposes a method for ventricular late potentials (VLPs) detection using time-frequency representation and wavelet denoising in high-resolution electrocardiography (HRECG). The analysis is performed both with the signal averaged electrocardiography (SAECG) and in real time. A comparison between the temporal and the time-frequency analysis is also reported. In the first analysis the standard parameters QRSd, LAS40, and RMS40 were used; in the second normalized energy in time-frequency domain was calculated. The algorithm was tested adding artificial VLPs to real ECGs.

Primary Prevention of Heart Failure

Javed Butler — Thu, 16 Aug 2012 13:09:58 +0000

Most heart failure research and quality improvement efforts are targeted at treatment and secondary prevention of patients with manifest heart failure. This is distinct from coronary disease where primary prevention has been a focus for over three decades. Given the current importance and the projected worsening of heart failure epidemiology, a more focused effort on prevention is urgently needed.

Effect of Staged Preconditioning on Biochemical Markers in the Patients Undergoing Coronary Artery Bypass Grafting

Thu, 02 Aug 2012 10:23:03 +0000

The present study has investigated the effectiveness of staged-preconditioning, in both remote and target organs. After IP the myocardial release of the biochemical markers including, creatine phosphokinase (CPK), cardiac creatine kinase (CK-MB), cardiac troponin T (cTnT) and lactate dehydrogenase (LDH) were evaluated in patients who underwent CABG, with and without staged-preconditioning. Sixty-one patients entered the study; there were 32 patients in the staged-preconditioning group and 29 patients in the control group. All patients underwent on-pump CABG using cardiopulmonary bypass (CPB) techniques. In the staged-preconditioning group, patients underwent two stages of IP on remote (upper limb) and target organs. Each stage of preconditioning was carried out by 3 cycles of ischemia and then reperfusion. Serum levels of biochemical markers were immediately measured postoperatively at 24, 48 and 72 h. Serum CK-MB, CPK and LDH levels were significantly lower in the staged-preconditioning group than in the control group. The CK-MB release in the staged-preconditioning patients reduced by 51% in comparison with controls over 72 h after CABG. These results suggest that myocardial injury was attenuated by the effect of three rounds of both remote and target organ IP.