bluuebunny/crossref_metadata_2025 huggingface dataset:
Immediate and one-year safety of intracoronary ultrasonic imaging. Evaluation with serial quantitative angiography.
Authors: Pinto F J , St Goar F G , Gao S Z , Chenzbraun A , Fischell T A , Alderman E L , Schroeder J S , Popp R L
Published: June 2012

BACKGROUND

Intracoronary ultrasound (ICUS) has the ability to quantitatively evaluate vessel wall morphology and is well suited for serial studies of coronary artery disease regression and progression. However, the potential risk for catheter-induced endothelial damage and accelerated atherosclerosis in instrumented vessels is a concern. The acute effects as well as the 1-year safety of ICUS regarding its impact on the atherosclerotic process were assessed.

METHODS AND RESULTS

The acute studies include 240 intracoronary studies performed in 170 cardiac transplant recipients. Patients were systematically heparinized. Only vessels > or = 2 mm in diameter were visualized. Coronary arteries of 38 patients were measured by quantitative coronary angiography in matched angiograms at an interval of 1 year after the initial ICUS examination was performed to assess long-term effects. The angiographic measurements in the previously instrumented and noninstrumented vessels were compared. Forty-nine vessels that had been imaged (IM) in these 38 patients with a 5F ICUS catheter were compared with 61 vessels not previously imaged (NIM) in the same patients. Absolute and percentage change in angiographically measured mean vessel diameters in the ICUS imaged and nonimaged segments were compared. Despite pretreatment with nitroglycerin, 20 patients (8.3%) had angiographically evident coronary spasm. In all cases, this was reversed by giving nitroglycerin. One year after the original imaging study, no difference was noted between imaged and nonimaged vessels in change in absolute vessel diameter (IM, -0.11 +/- 0.28 mm vs NIM, -0.07 +/- 0.22 mm; P = .49) or in percentage change in diameter (IM, -5 +/- 11% vs NIM, -3 +/- 7%; P = .32).

CONCLUSIONS

Intracoronary ultrasound in cardiac transplant recipients was associated with no clinical morbidity and a low incidence of vessel spasm in large and medium-size coronary arteries. It does not accelerate progression of angiographically quantifiable coronary artery disease. This study suggests that ICUS can be safely used even in coronary arteries not undergoing interventions.
Three-dimensional echocardiography. In vivo validation for left ventricular volume and function.
Authors: Siu S C , Rivera J M , Guerrero J L , Handschumacher M D , Lethor J P , Weyman A E , Levine R A , Picard M H
Published: June 2012

BACKGROUND

Current two-dimensional quantitative echocardiographic methods of volume assessment require image acquisition from standardized scanning planes. Left ventricular volume and ejection fraction are then calculated by assuming ventricular symmetry and geometry. These assumptions may not be valid in distorted ventricles. Three-dimensional echocardiography can quantify left ventricular volume without the limitations imposed by the assumptions of two-dimensional methods. We have developed a three-dimensional system that automatically integrates two-dimensional echocardiographic images and their positions in real time and calculates left ventricular volume directly from traced endocardial contours without geometric assumptions.

METHODS AND RESULTS

To study the accuracy of this method in quantifying left ventricular volume and performance in vivo, a canine model was developed in which instantaneous left ventricular volume can be measured directly with an intracavitary balloon connected to an external column. Ten dogs were studied at 84 different cavity volumes (4 to 85 cm3) and in conditions of altered left ventricular shape produced by either coronary occlusion or right ventricular volume overload. To demonstrate clinical feasibility, 19 adult human subjects were then studied by this method for quantification of stroke volume. Left ventricular volume, stroke volume, and ejection fraction calculated by three-dimensional echocardiography correlated well with directly measured values (r = .98, .96, .96 for volume, stroke volume, and ejection fraction, respectively) and agreed closely with them (mean difference, -0.78 cm3, -0.60 cm3, -0.32%). In humans, there was a good correlation (r = .94, SEE = 4.29 cm3) and agreement (mean difference, -0.98 +/- 4.2 cm3) between three-dimensional echocardiography and Doppler-derived stroke volumes.

CONCLUSIONS

Three-dimensional echocardiography allows accurate assessment of left ventricular volume and systolic function.
Accuracy of electronic digital calipers compared with quantitative angiography in measuring coronary arterial diameter.
Authors: Uehata A , Matsuguchi T , Bittl J A , Orav J , Meredith I T , Anderson T J , Selwyn A P , Ganz P , Yeung A C
Published: June 2012

BACKGROUND

Quantitative angiography is the accepted method for measuring coronary luminal diameter. Electronic digital calipers have been used to assess arterial diameters in vasomotor function studies and after interventional procedures. However, careful validation of calipers against quantitative angiography has not been described.

METHODS AND RESULTS

We used digital calipers and quantitative angiography to measure 517 arterial diameters (88 nonstenotic segments) in 24 transplant patients undergoing vasomotor function studies with acetylcholine and nitroglycerin, 20 stenoses in 14 patients with coronary artery disease, and 15 stenoses in 15 patients before and after excimer laser-facilitated coronary angioplasty and at 6 months' follow-up. In nonstenotic arterial segments ranging in size from 0.6 to 3.5 mm, calipers overestimated diameters measured by quantitative angiography by 0.29 +/- 0.21 mm (mean +/- SD) (limits of agreement, -0.13 to 0.71 mm). However, when the vasomotor responses were expressed as percent diameter change, the two methods did not differ significantly (-1 +/- 10%; limits of agreement, -21% to 19%). In the 35 stenoses measured before intervention and 30 stenoses measured after intervention, calipers and quantitative angiography differed by 3 +/- 9% (limits of agreement, -15% to 21%) across a range of stenosis severity (11% to 80%). Repeat caliper measurements by the same observer of the percent diameter change in the transplant patients and the percent stenosis in the coronary artery disease patients led to standard deviations of the differences of 9.3% and 7.6%, respectively. Two different observers recorded percent diameter change and percent stenosis that differed with standard deviations of 9.6% and 7.8%, respectively.

CONCLUSIONS

Quantitative angiography and electronic digital calipers produce similar relative changes in arterial diameters and percent stenosis in a broad range of severities. Digital calipers thus are a rapid and convenient alternative to computerized quantitative angiography in certain research studies and clinical practice of assessing stenosis severity.
A simple ultrasound approach for detection of recurrent proximal-vein thrombosis.
Authors: Prandoni P , Cogo A , Bernardi E , Villalta S , Polistena P , Simioni P , Noventa F , Benedetti L , Girolami A
Published: June 2012

BACKGROUND

The objective of this study was to develop a simple ultrasound method for measuring thrombus regression in patients with proximal deep-vein thrombosis (DVT) and to test its utility for the detection of DVT recurrence.

METHODS AND RESULTS

The study comprised a cross-sectional survey and a prospective investigation (149 and 145 patients, respectively). In both phases, the normalization rate of a previously abnormal ultrasound test, applying the criterion of full compressibility of the common femoral and popliteal veins (C-US method), was assessed. In the prospective study, the vein diameter under maximum compression (thrombus thickness) was measured in the abnormal venous segments at scheduled times (1, 3, 6, and 12 months). In patients presenting with suspected DVT recurrence, the procedure was repeated and results were compared with those available from the previous examination. Noncompressibility of a previously normal(ized) venous segment and enlargement of thrombus thickness (> or = 2 mm) were considered diagnostic of proximal DVT recurrence. The diagnostic accuracy of the C-US method alone, as well as of the combined ultrasound methods (C-US + thrombus thickness), was assessed against contrast phlebography. C-US test normalization occurred in only 30% of patients within 1 year. A significant reduction of the thrombus mass (P < .0001) was recorded throughout the entire study period. However, a major decrease in thrombus mass (> 50%) was recorded within the first 3 months. Of 29 patients who developed a suspected recurrent DVT, phlebography confirmed diagnosis in 11. The C-US method alone showed an excellent accuracy (100%) but was applicable in only 6 patients (21%). Both the sensitivity and the specificity for proximal DVT recurrence of the combined ultrasound methods were 100% (95% confidence interval, 69% to 100% and 81% to 100%, respectively) and were applicable in all patients.

CONCLUSIONS

The serial ultrasound measurement of thrombus mass after an acute episode of DVT may allow the correct identification of patients who develop a recurrent proximal-vein thrombosis.
Persistent T-wave changes after alteration of the ventricular activation sequence. New insights into cellular mechanisms of 'cardiac memory'.
Authors: Geller J C , Rosen M R
Published: June 2012

BACKGROUND

"Cardiac memory" refers to persistent T-wave changes on ECG that follow resumption of sinus rhythm after a period of altered activation sequence. Previous studies demonstrated that cardiac memory in intact dogs was abolished by 4-aminopyridine (4-AP), which blocks both the transient outward potassium current, Ito, and IK.

METHODS AND RESULTS

We used standard microelectrode techniques to study the mechanism for cardiac memory in canine ventricular subepicardial and subendocardial slabs measuring 15 x 30 x 1 to 2 mm. Bipolar electrodes were used to stimulate slabs parallel to fiber axis, simulating normal activation, and perpendicular to fiber axis, simulating ventricular pacing. Four 30-minute periods of normal activation at a basic cycle length of 650 milliseconds were interrupted by three 20-minute periods of ventricular pacing at a basic cycle length of 450 milliseconds. We first recorded action potentials differentially from epicardial and endocardial slabs. The stimulation protocol induced changes in the "T" wave of the difference signals that mimicked cardiac memory and that could be explained on the basis of the transmural gradient in repolarization between epicardium and endocardium. This result was not obtainable with slow and rapid pacing from one site only. In subsequent experiments, action potential characteristics of epicardial and endocardial slabs were studied by the same pacing protocol with alternation between simulated normal activation and ventricular pacing. During ventricular pacing, the epicardial phase 1 notch and plateau amplitude decreased compared with normal activation. 4-AP (3 mmol/L) decreased notch size and plateau amplitude during normal activation in epicardium but not endocardium. In contrast, the local anesthetic lidocaine did not change notch size or plateau amplitude in epicardium or endocardium.

CONCLUSIONS

These results suggest that the contribution to repolarization of specific potassium channels influences the memory phenomenon and that by blocking Ito and reducing the transmural voltage gradient for repolarization, 4-AP abolishes cardiac memory.
Augmented efficacy of external CPR by intermittent occlusion of the ascending aorta.
Authors: Tang W , Weil M H , Noc M , Sun S , Gazmuri R J , Bisera J
Published: June 2012

BACKGROUND

After prolonged cardiac arrest, conventional methods of closed-chest cardiac compression are ineffective. This is primarily because of failure to generate minimal threshold levels of coronary perfusion pressure for cardiac resuscitation. This report introduces a new option for cardiac resuscitation by use of a combination of intermittent ascending aortic balloon occlusion, aortic infusion, and precordial compression to increase the pressure gradient for coronary perfusion.

METHODS AND RESULTS

Twenty anesthetized, mechanically ventilated, normovolemic domestic pigs were investigated. A 10F balloon catheter was advanced from the left femoral artery into the ascending aorta. Ventricular fibrillation was induced with an AC current delivered through an electrode catheter advanced into the right ventricle. Precordial compression was initiated after 7 minutes of untreated ventricular fibrillation. The animals were randomized to one of four groups: (1) balloon occlusion with proximal infusion of oxygenated saline, (2) balloon occlusion alone, (3) proximal aortic infusion together with epinephrine without balloon occlusion, and (4) injection of epinephrine without balloon occlusion or proximal infusion. For balloon occlusion, the balloon was inflated for 30 seconds during each minute of cardiopulmonary resuscitation. In the subsets of animals that received infusions, oxygenated saline (30 mL) was injected into the proximal aorta immediately after balloon occlusion. Epinephrine was used in two subsets: It was injected as a bolus in amounts of 30 micrograms/kg into the right atrium at 30 seconds after start of precordial compression and repeated as required to maintain coronary perfusion pressure within the range of 25 to 30 mm Hg. Defibrillation was attempted at 1 minute after start of precordial compression and at 1-minute intervals thereafter. Resuscitation attempts were continued until there was return of spontaneous circulation or for a total of 30 minutes after start of precordial compression. Coronary perfusion pressure generated by precordial compression was significantly increased after balloon occlusion. Each of 10 animals was successfully resuscitated and survived for 48 hours after balloon occlusion whether or not it was combined with infusion. Three of five animals were resuscitated by a combination of infusion and epinephrine in the absence of aortic occlusion, but none survived for 48 hours (P = .02). Only one epinephrine-treated animal was successfully resuscitated and survived for 48 hours in the absence of balloon occlusion or infusion (P < .05).

CONCLUSIONS

Ascending aortic balloon occlusion with or without proximal aortic infusion strikingly increased resuscitability and 48-hour survival after cardiac arrest under conditions when conventional methods failed.
Socioeconomic factors and cardiovascular disease: a review of the literature.
Authors: Kaplan G A , Keil J E
Published: June 2012

Despite recent declines in mortality, cardiovascular diseases are the leading cause of death in the United States today. It appears that many of the major risk factors for coronary disease have been identified. Researchers are still learning about different modifiable factors that may influence cardiovascular diseases. Socioeconomic status may provide a new focus. The principal measures of SES have been education, occupation, and income or combinations of these. Education has been the most frequent measure because it does not usually change (as occupation or income might) after young adulthood, information about education can be obtained easily, and it is unlikely that poor health in adulthood influences level of education. However, other measures of SES have merit, and the most informative strategy would incorporate multiple indicators of SES. A variety of psychosocial measures--for example, certain aspects of occupational status--may be important mediators of SES and disease. The hypothesis that high job strain may adversely affect health status has a rational basis and is supported by evidence from a limited number of studies. There is a considerable body of evidence for a relation between socioeconomic factors and all-cause mortality. These findings have been replicated repeatedly for 80 years across measures of socioeconomic level and in geographically diverse populations. During 40 years of study there has been a consistent inverse relation between cardiovascular disease, primarily coronary heart disease, and many of the indicators of SES. Evidence for this relation has been derived from prevalence, prospective, and retrospective cohort studies. Of particular importance to the hypothesis that SES is a risk factor for cardiovascular disease was the finding by several investigators that the patterns of association of SES with coronary disease had changed in men during the past 30 to 40 years and that SES has been associated with the decline of coronary mortality since the mid-1960s. However, the declines in coronary mortality of the last few decades have not affected all segments of society equally. There is some evidence that areas with the poorest socioenvironmental conditions experience later onset in the decline in cardiovascular mortality. A number of studies suggest that poor living conditions in childhood and adolescence contribute to increased risk of arteriosclerosis. Some of these studies have been criticized because of their nature, and others for inadequate control of confounding factors.(ABSTRACT TRUNCATED AT 400 WORDS)
Evaluation of bioprosthetic valve-associated thrombus in ventricular assist device patients.
Authors: Wagner W R , Johnson P C , Kormos R L , Griffith B P
Published: June 2012

BACKGROUND

Thromboembolic events may be related to thrombotic deposition on prosthetic valves. In a left ventricular assist device (LVAD) that contains two porcine pericardial bioprosthetic valves in addition to significant associated biomaterial placement, this may be particularly true. Thrombotic deposits on valves removed from LVADs at autopsy or heart transplantation were scored to determine (1) the nature and location of valvular deposition, (2) whether deposition was related to thromboembolic events, (3) correlations between deposition and patient hemodynamic and coagulation parameters, and (4) implant time dependency.

METHODS AND RESULTS

Novacor LVADs were implanted in 23 patients as a bridge to transplantation for 1 to 303 days. Photographs of the concave (downstream) and convex (upstream) side of the inflow and outflow valve were made at explant and later scored for (1) total thrombus area (10 = equivalent of cusp area), (2) percent of cusp area occupied by solid thrombus, (3) thrombus color (10 = dark red, 0 = white), and (4) average percent of valve strut height involved with thrombus (from a side view). The inflow valve was shown to have heavier and redder deposition than the outflow valve. This was also true for the concave versus the convex side. Heaviest deposition was seen on the inflow valve concave side, which rests within the LVAD pumping sac and may be subject to poor convection. Patients with neurological thromboembolic events (8/23) during implantation had heavier deposition on the inflow valve concave side (5.7 +/- 2.7 versus 4.6 +/- 2.2, P < .05). Pump volumetric output was also found to negatively correlate with thrombus area on this valve and side (r = -.61, P = .002). Platelet release (platelet factor 4) was correlated with thrombus involvement on the upstream (convex) side of the inflow valve (r = .82, P = .002). No significant dependence of deposition on the implant time was found.

CONCLUSIONS

Valve thrombus deposition was related to thromboembolic events. Pump volumetric output and platelet release were found to be related to deposition. These results may have implications for the role of hemodynamics and platelet activation in thromboembolism associated with prosthetic valve placement in general.
Predictive value of tissue plasminogen activator mass concentration on long-term mortality in patients with coronary artery disease. A 7-year follow-up.
Authors: Jansson J H , Olofsson B O , Nilsson T K
Published: June 2012

BACKGROUND

The fibrinolytic system is part of the defense against thrombotic and cardiovascular events, but so far no study has shown that clinical measurements of fibrinolytic key components such as tissue plasminogen activator (t-PA) or plasminogen activator inhibitor type 1 (PAI-1) have any predictive value beyond 3 years.

METHODS AND RESULTS

In 1983 through 1985, 213 consecutive patients with angina pectoris and angiographically verified coronary artery disease were sampled, and the mass concentration of t-PA and the activity of PAI-1 were measured in citrated plasma samples. At a mean follow-up time of 7 years, the all-cause mortality was checked. No patient was lost to follow-up. The data were analyzed by Cox regression, and t-PA mass concentration was found to be the only laboratory risk factor significantly related to mortality in all patients (P < .022) and also in the major subgroup (78% of all patients) subjected to coronary bypass surgery (P < .027). In the latter subgroup, body mass index was also related to mortality.

CONCLUSIONS

An increased mass concentration of t-PA is a new risk factor of long-term mortality in patients with angina pectoris and coronary artery stenosis. This paradoxical effect probably reflects increased t-PA levels attributable to enzyme inhibitor complex formation in subjects with increased plasma levels of t-PA inhibitors.
Safety and efficacy of recombinant hirudin (CGP 39 393) versus heparin in patients with stable angina undergoing coronary angioplasty.
Authors: van den Bos A A , Deckers J W , Heyndrickx G R , Laarman G J , Suryapranata H , Zijlstra F , Close P , Rijnierse J J , Buller H R , Serruys P W
Published: June 2012

BACKGROUND

Enhanced thrombin activity has been associated with acute and long-term complications following balloon angioplasty (percutaneous transluminal coronary angioplasty (PTCA). We evaluated, in a 2-to-1 randomized, double-blind trial, the effects of recombinant hirudin, CGP 39 393, relative to unfractionated sodium heparin on periprocedural events, bleeding, early angiographic outcome, and coagulation in 113 patients with stable angina undergoing PTCA.

METHODS AND RESULTS

Prior to PTCA, 20 mg CGP 39 393 was administered as a bolus, followed by continuous infusion at a rate of 0.16 mg.kg-1 x h-1, or 10,000 IU sodium heparin was administered as a bolus and continued at a rate of 12 IU.kg-1 x h-1 for 24 hours. Infusion was adjusted to activated partial thromboplastin time (APTT) levels. ST segment was monitored for 24 hours, and angiograms were analyzed with quantitative technique (QCA). In 74 CGP 39 393- and 39 heparin-treated patients, 132 lesions were dilated. Myocardial infarction and/or emergency coronary bypass surgery occurred in 1 (1.4%) CGP 39 393 patient compared with 4 (10.3%) heparin patients (relative risk, 7.6; 95% confidence interval, 0.9, 65.6). At 24 hours, complete perfusion was present in 91% heparin and 100% CGP 39 393 patients. Significant ST segment displacement was found in 11% of heparin versus 4% of CGP 39 393 subjects. Bleeding occurred only at the puncture site in 4 CGP 39 393-treated patients. QCA did not reveal significant differences between the groups. APTT values were more often in the target range and more stable in CGP 39 393 patients. Levels of thrombin-antithrombin III complexes, prothrombin fragment F1+2, and fibrinopeptide A indicated that CGP 39 393 was an effective inhibitor of thrombin activity.

CONCLUSIONS

CGP 39 393 can safely be administered to patients undergoing elective PTCA for stable anginal symptoms and may have a more favorable anticoagulant profile than heparin.
Interference of glycosylated human hemoglobin with endothelium-dependent responses.
Authors: Rodríguez-Mañas L , Arribas S , Girón C , Villamor J , Sánchez-Ferrer C F , Marín J
Published: June 2012

BACKGROUND

Hypertension and other vascular diseases are more prevalent in diabetic patients than in the general population. In humans and in several animal models of diabetes, a disturbance of endothelium-dependent responses has been shown. Oxyhemoglobin is one of the most known modulators of these endothelium-dependent responses. We postulate that high levels of plasmatic glycosylated hemoglobin, a frequent profile in diabetic patients, may be the cause of the disturbance in endothelium-dependent relaxation and/or contraction.

METHODS AND RESULTS

Endothelium-dependent responses to acetylcholine and several alpha-adrenergic agonists (norepinephrine, methoxamine, and clonidine) were tested in segments of rat aorta. Experiments were carried out in control segments and in those preincubated with several concentrations of nonglycosylated, low-glycosylated (7.3%), and high-glycosylated (14%) human hemoglobin. Low concentrations of high-glycosylated human hemoglobin (1 to 100 nmol/L) but not of low- or nonglycosylated hemoglobin, inhibited endothelium-dependent relaxation caused by acetylcholine in intact vessels. The same effect was observed on relaxations caused by nitric oxide in denuded ones. High-glycosylated human hemoglobin (10 nmol/L) induced an increase in norepinephrine-evoked contraction in intact vessels; this latter effect was also shown in vessels contracted with methoxamine but not with clonidine. De-endothelialization of the vascular segments blunted these effects of high-glycosylated human hemoglobin.

CONCLUSIONS

High glycosylation of human hemoglobin impairs endothelium-mediated vasoactive responses and may play a pathophysiological role in producing hypertension and vascular diseases in diabetic patients.
Associations of postmenopausal estrogen use with cardiovascular disease and its risk factors in older women. The CHS Collaborative Research Group.
Authors: Manolio T A , Furberg C D , Shemanski L , Psaty B M , O'Leary D H , Tracy R P , Bush T L
Published: June 2012

BACKGROUND

Postmenopausal estrogen replacement therapy has been associated with favorable levels of cardiovascular disease risk factors, but these associations and the relations between estrogen use and subclinical disease have not been examined in large samples of older women.

METHODS AND RESULTS

Present and past estrogen use was ascertained in 2955 women > or = 65 years old in the Cardiovascular Health Study, a study of risk factors for coronary heart disease and stroke in the elderly. Present estrogen use was reported by 12% of these women and past use by an additional 26.5%. Estrogen use (past or present) was strongly associated with lower low-density lipoprotein cholesterol, fibrinogen, glucose, insulin, obesity, and age and higher high-density lipoprotein cholesterol and socioeconomic status (all P < .0001). Estrogen users also had lower levels of subclinical disease as measured by carotid intimal-medial thickness, carotid stenosis grade, ECG left ventricular mass, and Doppler mitral peak flow velocities (each P < .02). Relations were similar in younger and older women (65 to 74 versus > or = 75 years) and smokers and nonsmokers and were unchanged after women with poor medication compliance were excluded. After adjustment for other factors, estrogen use was associated with decreased carotid wall thickness, although this association was of borderline significance after further adjustment for lipids.

CONCLUSIONS

Postmenopausal estrogen use in this sample of older women was associated with favorable cardiovascular disease risk factor profiles and with lower measures of subclinical disease. These findings suggest that postmenopausal estrogen use may be associated with lower risk of cardiovascular disease in women well into the eighth decade of life.
Socioeconomic status and coronary heart disease risk factor trends. The Minnesota Heart Survey.
Authors: Luepker R V , Rosamond W D , Murphy R , Sprafka J M , Folsom A R , McGovern P G , Blackburn H
Published: June 2012

BACKGROUND

Socioeconomic status (SES) indicators including education, income, and occupation are associated with coronary heart disease (CHD) risk factors, morbidity, and mortality. In most industrialized nations, individuals with less education, lower income, and blue collar occupations have the highest CHD rates. It is suggested by some that these differences by SES are increasing even as age-adjusted CHD mortality declines.

METHODS AND RESULTS

The Minnesota Heart Survey includes measurement of CHD risk factors and behaviors in population-based samples of Minneapolis-St. Paul adults aged 25 to 74 years in 1980 to 1982 (N = 3243) and 1985 to 1987 (N = 4538). Education was significantly and inversely related to blood pressure, cigarette smoking, body mass index, and a summary risk score for both men and women. Serum cholesterol was inversely related to education in women but not in men. Education was positively associated with leisure physical activity and health knowledge. Associations with household income were less consistent in magnitude and direction. Risk characteristics improved significantly between the 1980 to 1982 and 1985 to 1987 surveys. These changes were similar across education and household income levels.

CONCLUSIONS

Improvement in CHD risk factors over time unrelated to education or income suggests that population-wide factors such as improved health knowledge, availability of healthy food items, hypertension treatment, and restrictions on cigarette smoking are operating beneficially in all SES groups. Although the SES gradient in risk factors is not increasing, it remains substantial and indicates directions for future prevention efforts.
Regional left ventricular mechanics in hypertrophic cardiomyopathy.
Authors: Betocchi S , Hess O M , Losi M A , Nonogi H , Krayenbuehl H P
Published: June 2012

BACKGROUND

Nonuniformity is a determinant of diastolic function. In patients with hypertrophic cardiomyopathy, hypertrophy, abnormal calcium handling, and regional ischemia can also play a role. This study was designed to assess regional mechanics, asynchrony, and asynergy in patients with hypertrophic cardiomyopathy.

METHODS AND RESULTS

Nine control subjects and 22 patients with hypertrophic cardiomyopathy were studied by biplane left ventriculography and high-fidelity pressure tracings for the assessment of diastolic function by computing the time constant of isovolumic relaxation, peak filling rate, and the constant of passive chamber stiffness. Regional mechanics were evaluated by dividing the left ventricle into six sectors in the right and left anterior oblique projections. Systolic and diastolic asynchrony were assessed from the coefficient of variation of the regional time intervals from end diastole to end systole and to peak filling rate, respectively. Asynergy was evaluated from the coefficient of variation of the regional area reduction. Regional passive elastic properties were estimated by computing the regional constant of chamber stiffness. In patients with hypertrophic cardiomyopathy, isovolumic relaxation was prolonged (time constant of isovolumic relaxation 101 +/- 41 versus 51 +/- 16 milliseconds in control subjects; P < .001) and the constant of chamber stiffness was increased (0.056 +/- 0.038 versus 0.025 +/- 0.010 mL-1; P < .001). Both systolic and diastolic asynchrony as well as asynergy were found. Regional mechanics showed hyperkinesia in the free wall, whereas the septum exhibited normal wall motion and increased constant of chamber stiffness.

CONCLUSIONS

Diastolic function is impaired in hypertrophic cardiomyopathy, and such an impairment is the consequence of nonuniformity and hypertrophy. The regions where the myopathic process is more pronounced show normal wall motion but increased stiffness. The inhomogeneity of regional wall motion with regional hyperkinesia and normokinesia of neighboring regions results in left ventricular asynergy.
Helical and retrograde secondary flow patterns in the aortic arch studied by three-directional magnetic resonance velocity mapping.
Authors: Kilner P J , Yang G Z , Mohiaddin R H , Firmin D N , Longmore D B
Published: June 2012

BACKGROUND

Helical and retrograde secondary flows have been recorded in the aorta, but their origins and movements in relation to the arch have not been clarified. We set out to do this using magnetic resonance velocity mapping.

METHODS AND RESULTS

Three-directional phase contrast cine magnetic resonance velocity mapping was used to map multidirectional flow velocities in the aortas of 10 healthy volunteers. Computer processing was used to visualize flow vector patterns in selected planes. Right-handed helical flows predominated in the upper aortic arch in late systole, being clearly recognizable in 9 of the 10 subjects. Nonaxial components of velocity in this region reached 0.29 m/s (+/- 0.05 m/s) as axial velocities declined from a peak of 1.0 m/s (+/- 0.1 m/s). Helical flow patterns in the upper descending aorta varied between subjects, apparently depending on arch curvature. End-systolic retrograde flow originated from regions of blood with low momentum, usually along inner wall curvatures. Flow studies in a curved tubular phantom showed right-handed helical flow in the upper "arch" when the inflow section was positioned to simulate ascending aortic curvature, and retrograde flow occurred along the inner wall at end systole during pulsatile flow.

CONCLUSIONS

Helical and retrograde streams are consistent features of intra-aortic flow in healthy subjects that result, at least in part, from the curvature of the arch and the pulsatility of flow in it. They may have significance in relation to circulatory dynamics and the pathogenesis of atheroma in the arch.
Influence of right heart size on outcome in pulmonary atresia with intact ventricular septum.
Authors: Giglia T M , Jenkins K J , Matitiau A , Mandell V S , Sanders S P , Mayer J E , Lock J E
Published: June 2012

BACKGROUND

Neonates with pulmonary atresia and intact ventricular septum (PA-IVS) are frequently born with hypoplastic right heart structures that must grow after right ventricular decompression (RVD) procedures for a complete two-ventricle physiology to be achieved. Previous authors have asserted that neonatal right heart size or morphology will predict right heart growth potential. Since 1983, our bias has favored early RVD regardless of initial right heart size. In 1986, we recognized a subset of patients with coronary artery abnormalities associated with poor outcome after RVD and have defined these patients as having a right ventricular-dependent coronary circulation (RVDCC).

METHODS AND RESULTS

To assess the influence of right heart size on outcome independent of the presence of RVDCC, we measured echocardiographic right ventricular (RV) dimensions in 37 neonates with adequate studies presenting between 1983 and 1990. Coronary artery anatomy was adequately assessed by angiography in 36. RV volume and tricuspid valve (TV) diameter were significantly smaller in patients with RVDCC than in those without. However, there was no statistically significant association between RV volume or TV diameter and survival among patients with or without RVDCC: Among 29 patients without RVDCC, 23 of 24 (95.8%) who achieved RVD are alive compared with 1 of 5 (20%) who did not achieve RVD (P = .001). Twenty-one of the 23 survivors have a complete two-ventricle physiology with low right atrial pressure. Among 7 patients with RVDCC, 2 patients who underwent RVD died early of left ventricular failure, whereas 4 of 5 who did not undergo RVD have survived single ventricular palliation.

CONCLUSIONS

Small right heart size is associated with RVDCC but is not associated with survival in PA-IVS. Patients without RVDCC have improved survival after RVD regardless of neonatal right heart size.
Effects of the angiotensin converting enzyme inhibitor enalapril on the long-term progression of left ventricular dilatation in patients with asymptomatic systolic dysfunction. SOLVD (Studies of Left Ventricular Dysfunction) Investigators.
Authors: Konstam M A , Kronenberg M W , Rousseau M F , Udelson J E , Melin J , Stewart D , Dolan N , Edens T R , Ahn S , Kinan D
Published: June 2012

BACKGROUND

Patients with heart failure and reduced left ventricular (LV) ejection fraction (EF) manifest progressive LV dilatation, which is prevented by angiotensin converting enzyme (ACE) inhibitors. In patients with asymptomatic LV systolic dysfunction, in whom there is less activation of the renin-angiotensin system, ventricular remodeling might be less rapid and the benefit of ACE inhibitors less discernible.

METHODS AND RESULTS

One hundred eight patients enrolled in the Studies of Left Ventricular Dysfunction (SOLVD) Prevention Trial, with left ventricular ejection fraction < or = 0.35 but without clinical heart failure, underwent radionuclide ventriculograms, and 49 underwent left heart catheterizations. Measurements were made before and after double-blinded randomization to enalapril (2.5 to 20 mg/d) or placebo. Repeated-measures analysis of all time points showed significant differences for change in end-diastolic volume (EDV) between enalapril and placebo groups. Significant difference between the enalapril and placebo groups (P < .05) was present for change in EDV at 1 year within the catheterization study and at a mean of 25 months within the radionuclide study. Radionuclide EDV increased in placebo patients (119 +/- 28 to 124 +/- 33 mL/m2, mean +/- SD) and decreased in enalapril patients (120 +/- 25 to 113 +/- 25 mL/m2). Differences between the two groups were significantly less than previously described in patients with symptomatic heart failure (P < .02), with less increase in LV volumes in the placebo group and less decrease in volumes in the enalapril group.

CONCLUSIONS

Chronic ACE inhibitor treatment slows or reverses LV dilatation in patients with asymptomatic LV systolic dysfunction. Compared with symptomatic patients, asymptomatic patients manifest a slower rate of spontaneous LV dilatation and less reduction in LV volumes by enalapril.
Use-dependent block of the pacemaker current I(f) in rabbit sinoatrial node cells by zatebradine (UL-FS 49). On the mode of action of sinus node inhibitors.
Authors: Goethals M , Raes A , van Bogaert P P
Published: June 2012

BACKGROUND

Zatebradine (UL-FS 49) is a drug with a specific bradycardiac electrophysiological profile. It reduces heart rate by lengthening the duration of diastolic depolarization in the sinoatrial (SA) node. The ionic basis of this action, however, is not clarified.

METHODS AND RESULTS

We used the whole-cell patch-clamp technique to study the effects of zatebradine on ionic currents underlying diastolic depolarization of isolated rabbit SA node cells. Low concentrations of zatebradine simultaneously reduced diastolic depolarization rate and the pacemaker current I(f). The drug blocked the pacemaker current, I(f), in a use-dependent manner without causing a shift of its activation curve. At hyperpolarized potentials, unblock of I(f) occurred. Clinically relevant concentrations of the drug have little effect on the L-type calcium current or delayed rectifier potassium current.

CONCLUSIONS

This use-dependent block of the If channel can account for most of the pharmacological characteristics of zatebradine and is probably the mechanism of heart rate reduction caused by this agent. Thus, the sinus node inhibitor zatebradine belongs to a new class of "I(f) blockers" with possible advantages over currently available drugs for the treatment of ischemic heart disease.
Smooth muscle cell abundance and fibroblast growth factors in coronary lesions of patients with nonfatal unstable angina. A clue to the mechanism of transformation from the stable to the unstable clinical state.
Authors: Flugelman M Y , Virmani R , Correa R , Yu Z X , Farb A , Leon M B , Elami A , Fu Y M , Casscells W , Epstein S E
Published: June 2012

BACKGROUND

The mechanisms responsible for the transformation of stable angina to unstable angina, a major cause of morbidity and mortality, are commonly believed to be plaque rupture and thrombosis. We determined whether additional mechanisms are operative by analyzing the histopathology and immuno-histopathology of coronary plaques retrieved by directional atherectomy of patients with unstable angina in whom no intraluminal thrombus was demonstrated by angiography.

METHODS AND RESULTS

The histological findings of atherectomy specimens from 34 patients with unstable angina were compared with those of 24 patients with postangioplasty restenosis, whose lesions are known to be composed of smooth muscle cells (SMCs), and 10 patients with stable angina, whose lesions contain relatively few SMCs. We also studied the expression of acidic and basic fibroblast growth factors (aFGF and bFGF), whose role in the vascular response to injury has been established. Specimens from unstable angina resembled those from postangioplasty restenosis in regard to SMC abundance (scale, 0 to 3; 1.4 +/- 0.9 versus 1.7 +/- 0.9; P = NS), and both differed from those of stable angina. Thrombus and/or hemorrhage occurred in only 34% of patients with unstable angina (compared with 8% of restenosis patients and in none of stable angina patients). Active lesions (defined as lesions (defined as lesions containing one or more of the following: thrombus, hemorrhage, abundant and disorganized SMCs in the presence of loose connective tissue, or inflammatory infiltrate) were observed in 56% of the unstable angina patients and in 50% of the restenosis patients but in none of the stable angina patients. The expression of aFGF and bFGF was detected in 80% to 100% of unstable angina (n = 11) and restenosis (n = 10) specimens but in only 1 of 5 stable angina specimens.

CONCLUSIONS

Microscopic evidence of thrombosis and plaque rupture occurred in only one third of unstable angina patients, selected because they had no angiographic evidence of intracoronary thrombus. Moreover, their lesions resembled those of restenosis patients in regard to SMC abundance, lesion activity, and the expression of aFGF and bFGF. Our findings therefore suggest that an alternative mechanism to plaque rupture and thrombus formation may be operative in the precipitation of unstable angina; namely, in a subset of patients, SMC proliferation may lead to gradual plaque expansion and thereby to lumenal narrowing and unstable angina. Our data also suggest a role for aFGF and bFGF in this process.
Benefit of adding low molecular weight heparin to the conventional treatment of stable angina pectoris. A double-blind, randomized, placebo-controlled trial.
Authors: Melandri G , Semprini F , Cervi V , Candiotti N , Palazzini E , Branzi A , Magnani B
Published: June 2012

BACKGROUND

Patients with chronic coronary artery disease exhibit a dysfunctioning endothelium, which may be responsible for exercise-induced platelet activation and expression of a procoagulant moiety. In this study, we evaluated the therapeutic efficacy of a low molecular weight heparin (Parnaparin) in patients with stable angina pectoris.

METHODS AND RESULTS

According to a double-blind, randomized, placebo-controlled trial, 29 patients with stable exercise-induced angina pectoris and angiographically proven coronary artery disease received a single daily subcutaneous injection of Parnaparin or placebo on top of aspirin and conventional antianginal medication over 3 months. Patients randomized to Parnaparin showed a significant decrease in the fibrinogen level (P = .035) and an improvement in both the time to 1-mm ST segment depression (P = .008) and the peak ST segment depression (P = .015). The Canadian Cardiovascular Society class for angina pectoris was also improved by Parnaparin (P = .016). Parnaparin did not affect ADP and collagen-induced platelet aggregation, whereas thrombin-induced aggregation was reduced (P = .0001). The bleeding time was slightly prolonged, but this was not associated with any significant bleeding.

CONCLUSIONS

Patients with stable angina pectoris may be treated with Parnaparin in addition to aspirin and conventional antianginal medication. Side effects are negligible, and compliance is excellent.
The role of transesophageal echocardiography in identifying anomalous coronary arteries.
Authors: Fernandes F , Alam M , Smith S , Khaja F
Published: June 2012

BACKGROUND

The study objective was to evaluate the role of transesophageal echocardiography in identifying the origin of anomalous coronary arteries and confirming their course in relation to the great vessels. The diagnosis of coronary anomalies is made by angiography. The anomalous left main artery with a course between the pulmonary artery and the aorta has been associated with myocardial infarction and sudden death. The course of these anomalous coronary arteries is difficult to demonstrate by angiography alone.

METHODS AND RESULTS

Nine patients with angiographically confirmed anomalous coronary arteries were studied by transesophageal echocardiography with color flow Doppler. The abnormal origin of the anomalous coronary arteries was confirmed by transesophageal echocardiography in all nine patients. In four patients, the left main coronary artery originated from the right sinus of Valsalva. In all of these patients, transesophageal echocardiography demonstrated the course of the anomalous left main coronary artery between the aorta and pulmonary artery better than angiography. Other anomalies that were visualized included two patients with origin of the right coronary arteries from the left aortic sinus, one patient with origin of the left anterior descending from the right sinus, one patient with origin of circumflex from the right sinus, and one patient with origin of the left main coronary artery from the pulmonary artery.

CONCLUSIONS

Transesophageal echocardiography is a useful noninvasive test for diagnosing anomalous origin of the coronary arteries. Furthermore, it is a valuable adjunct to angiography in demonstrating the abnormal course of the left main coronary artery interposed between the aorta and the pulmonary artery, a potentially life-threatening entity.
Radiofrequency catheter ablation of idiopathic left ventricular tachycardia guided by a Purkinje potential.
Authors: Nakagawa H , Beckman K J , McClelland J H , Wang X , Arruda M , Santoro I , Hazlitt H A , Abdalla I , Singh A , Gossinger H
Published: June 2012

BACKGROUND

Verapamil-sensitive, idiopathic left ventricular tachycardia (ILVT) with right bundle branch block configuration and left-axis deviation has been suggested to originate from the left posterior fascicle. The purpose of this study was to determine how frequently potentials generated by the Purkinje fiber network (P potential) can be recorded preceding ventricular activation, and the role of the P potential in guiding radiofrequency catheter ablation.

METHODS AND RESULTS

Eight patients (mean age, 26 +/- 10 years) with ILVT (cycle length, 346 +/- 59 milliseconds) were studied. Right and left ventricular endocardial mapping during tachycardia identified earliest ventricular activation at the posteroapical left ventricular septum. In all patients, earliest ventricular activation during tachycardia was preceded by a distinct potential. This potential also preceded ventricular activation during sinus rhythm, consistent with activation of a segment of the left posterior fascicle (P potential). The earliest recorded P potential preceded the QRS during tachycardia by 15 to 42 milliseconds (mean, 27 +/- 9 milliseconds). The application of radiofrequency current at 1 to 4 sites (median, 1) eliminated ILVT in all eight patients. In the seven patients with P potentials recorded at multiple sites within the posteroapical septum, ablation was successful at the site of the earliest P potential and unrelated to the timing of ventricular activation. In the remaining patient, ablation was successful at a site recording a late P potential fusing with earliest ventricular activation. During follow-up (1 to 67 months; median, 10.5) ILVT recurred only in the latter patient. Pace mapping during tachycardia at the successful ablation site in four patients produced a similar QRS with stimulus-QRS interval equal to P-QRS interval during tachycardia. However, a similar QRS was obtained by pacing at nearby sites that recorded a later P potential.

CONCLUSIONS

These findings support the hypothesis that ILVT originates from the Purkinje network of the left posterior fascicle. A P potential can be recorded at the posteroapical left ventricular septum during ILVT, and ablation is successful at the site recording the earliest P potential. Pace mapping with similar QRS is not specific due to capture of the Purkinje fiber network at a site remote from the origin of the tachycardia.