bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three-year outcome after balloon aortic valvuloplasty. Insights into prognosis of valvular aortic stenosis.
Authors: Otto C M , Mickel M C , Kennedy J W , Alderman E L , Bashore T M , Block P C , Brinker J A , Diver D , Ferguson J , Holmes D R 
Published: June 2012

BACKGROUND
To identify predictors of long-term outcome after balloon aortic valvuloplasty, we analyzed data on 674 adults (mean age, 78 +/- 9 years; 56% were women) undergoing this procedure at 24 clinical centers who had a mean initial increase in aortic valve area of 0.3 cm2.

METHODS AND RESULTS
Baseline data included clinical, echocardiographic, and catheterization variables. Follow-up data included mortality, cause of death, rehospitalization, 6-month echocardiography, and functional status. Kaplan-Meier curves and log-rank tests were used to evaluate survival in subgroups. Multivariate Cox regression models were used to identify independent predictors of survival. Overall survival was 55% at 1 year, 35% at 2 years, and 23% at 3 years, with the majority of deaths (70%) classified as cardiac by an independent review committee. Rehospitalization was common (64%), although 61% of survivors at 2 years reported improved symptoms. Echocardiography at 6 months (n = 115) showed restenosis from the postprocedural valve area of 0.78 +/- 0.31 cm2 to 0.65 +/- 0.25 cm2 (P < .0001). With stepwise multivariate analysis, sequentially adding clinical, echocardiographic, and catheterization variables, the overall model identified independent predictors of survival as baseline functional status, baseline cardiac output, renal function, cachexia, female gender, left ventricular systolic function, and mitral regurgitation. Baseline and postprocedural variables were examined to identify which subgroup of patients has the best outcome after aortic valvuloplasty. A "lower-risk" subgroup (28% of the study population), defined by normal left ventricular systolic function and mild clinical functional limitation, had a 3-year survival of 36% compared with 17% in the remainder of the study group.

CONCLUSIONS
Long-term survival after balloon aortic valvuloplasty is poor with 1- and 3-year survival rates of 55% and 23%, respectively. Although survivors report fewer symptoms, early restenosis and recurrent hospitalization are common.
Contrasting effects of the intermittent and continuous administration of heparin in experimental restenosis.
Authors: Edelman E R , Karnovsky M J 
Published: June 2012

BACKGROUND
Heparin inhibits proliferation of smooth muscle cells in culture and intimal hyperplasia in experimental animals but paradoxically exacerbates vascular injury in clinical trials. To determine whether the difference in the means by which heparin was administered explained the benefit in animals and aggravation in humans, we examined the vascular effects of a range of heparin treatments.

METHODS AND RESULTS
When laboratory rats were injected subcutaneously with heparin (55.5 IU, approximately 1.0 mg/kg) per clinical trial protocols, intimal hyperplasia after arterial injury was exacerbated rather than alleviated. The intima to media area ratio was increased 22.5% with every-other-day injections and was increased 16.8% with daily injections. When the daily dose of heparin was increased to 7.2 mg/kg or when injections were initiated a week before injury, intimal hyperplasia was made even worse (52.2% and 59.9% above control). Twice-daily heparin, 7 and 17 hours apart, had no demonstrable effect one way or the other, and it was not until the heparin was administered at 12-hour intervals that intimal hyperplasia and cell proliferation were lessened (44.6% decrease). The greatest reduction in intimal hyperplasia was obtained when the heparin was administered continuously. The continuous osmotic pump intravenous infusion of heparin inhibited 62.5% of the expected proliferation, and perivascular polymeric device release of heparin blocked the response by 74.2%. While subcutaneous injections transiently increased activated partial thromboplastin time, neither mode of continuous delivery altered coagulation.

CONCLUSIONS
We might reconsider the use of heparin in vascular diseases and not neglect this promising compound because of inappropriate extrapolation from the laboratory to clinical use.
Use of the rabbit ear artery to serially assess foreign protein secretion after site-specific arterial gene transfer in vivo. Evidence that anatomic identification of successful gene transfer may underestimate the potential magnitude of transgene expression.
Authors: Losordo D W , Pickering J G , Takeshita S , Leclerc G , Gal D , Weir L , Kearney M , Jekanowski J , Isner J M 
Published: June 2012

BACKGROUND
The development of molecular strategies for the treatment of restenosis has been hindered by low efficiencies of in vivo arterial transfection. Expression of intracellular marker proteins is generally evident in < 1% of vascular smooth muscle cells after in vivo arterial transfection. Efforts to improve the efficiency of in vivo gene transfer have been further impeded by the use of transgenes encoding for intracellular marker proteins, necessitating tissue removal and limiting survey for expression to one point in time.

METHODS AND RESULTS
To study gene expression on a serial basis in vivo and determine the relation between a secreted gene product and transfection efficiency after in vivo arterial gene transfer, a method for performing and serially monitoring gene expression in vivo was developed using the central artery of the rabbit ear. Liposome-mediated transfection of plasmid DNA containing the gene for human growth hormone (hGH) was successfully performed in 18 of 23 arteries. Serum hGH levels measured 5 days after transfection ranged from 0.1 to 3.8 ng/mL (mean, 0.97 ng/mL); in contrast, serum drawn from the control arteries demonstrated no evidence of hGH production. Serial measurement of hGH from transfected arteries demonstrated maximum hGH secretion 5 days after transfection and no detectable hormone after 20 days. Despite these levels of secreted gene product documented in vivo, immunohistochemical staining of sections taken from the rabbit ear artery at necropsy disclosed only rare cells in which there was evidence of successful transfection.

CONCLUSIONS
These experiments demonstrate a useful method of performing serial in vivo analyses of gene expression after vascular transfection and that anatomic analyses of transfection efficiency may underestimate the potential magnitude of expression in the case of a secreted gene product. These findings have implications for the clinical application of somatic gene therapy because low-efficiency transfection with a gene encoding for a secreted protein may achieve therapeutic effects not realized by transfection with genes encoding for proteins that remain intracellular.
Predictive value of reactive hyperemic response on reperfusion on recovery of regional myocardial function after coronary angioplasty in acute myocardial infarction.
Authors: Suryapranata H , Zijlstra F , MacLeod D C , van den Brand M , de Feyter P J , Serruys P W 
Published: June 2012

BACKGROUND
The objective of the study was to determine the coronary vasodilatory reserve in reperfused myocardium in patients with acute myocardial infarction and its relation to regional myocardial function.

METHODS AND RESULTS
The study population consisted of 22 patients with acute myocardial infarction who underwent successful coronary angioplasty. The vasodilatory reserve in the reperfused myocardium was assessed quantitatively using computer-assisted digital subtraction cine-angiography immediately after angioplasty and at follow-up angiography before hospital discharge. Myocardial contrast medium appearance time and density were determined before and after pharmacological hyperemia induced by an intracoronary injection of 12.5 mg papaverine. Global and regional left ventricular functions were determined from contrast angiography. After papaverine, the mean contrast medium appearance time decreased significantly from 3.5 +/- 0.7 to 2.7 +/- 0.7 cardiac cycles (P < .000005) immediately after successful coronary angioplasty and from 3.8 +/- 0.7 to 2.7 +/- 0.9 cardiac cycles (P < .000005) at angiography before hospital discharge. The mean contrast medium density increased significantly from 48.7 +/- 13.8 to 61.0 +/- 19.0 pixels (P < .003) and from 49.6 +/- 19.7 to 80.3 +/- 29.6 pixels (P < .000005), respectively. As a consequence, the calculated coronary flow reserve increased significantly from 1.8 +/- 0.7 to 2.6 +/- 1.0 (P < .0008). The global ejection fraction increased significantly from 52 +/- 12% to 58 +/- 14% (P < .03), primarily because of a significant improvement in the regional myocardial function of the infarct zone from 20.8 +/- 9.0% to 26.0 +/- 10.5% (P < .001). Coronary flow reserve correlated well with regional myocardial function both during the acute phase (R = .79, P < .002) and at follow-up angiography (R = .82, P < .000004). Interestingly, coronary flow reserve measurement on reperfusion, immediately after angioplasty, correlated significantly with regional myocardial function at follow-up angiography (R = .81, P < .00003).

CONCLUSIONS
The results indicate that there is a pharmacologically inducible vasodilatory reserve in reperfused ischemic myocardium after successful coronary angioplasty in patients with acute myocardial infarction and that this is increased at 10-day follow-up angiography. More important, the degree of reactive hyperemic response on reperfusion has a predictive value regarding the ultimate degree of recovery of regional myocardial function. Quantitative assessment of reperfusion may be useful in investigating the role of coronary reperfusion and salvage of myocardial function.
Long-term graft patency (3 years) after coronary artery surgery. Effects of aspirin: results of a VA Cooperative study.
Authors: Goldman S , Copeland J , Moritz T , Henderson W , Zadina K , Ovitt T , Kern K B , Sethi G , Sharma G V , Khuri S 
Published: June 2012

BACKGROUND
The long-term success of coronary bypass surgery is dependent on graft patency after surgery. This trial was designed to determine if aspirin improved saphenous vein graft or internal mammary artery (IMA) graft patency between 1 and 3 years after coronary artery bypass grafting (CABG).

METHODS AND RESULTS
After receiving aspirin 325 mg/d for 1 year after CABG and undergoing a 1-year postoperative cardiac catheterization, patients were randomized to receive either aspirin (325 mg) or placebo for 2 additional years. Angiography was performed 3 years after surgery to determine the primary end point-saphenous vein graft patency in 288 patients and IMA graft patency in 167 patients. At 3 years after CABG, the saphenous vein graft occlusion rate was 17.0% (62 of 365) for patients treated with aspirin compared with 19.7% (74 of 376) for those who received placebo (P = .404). For saphenous vein grafts that were patent at 1 year, the occlusion rate at 3 years was 4.8% (15 of 313) for patients treated with aspirin compared with 4.2% (13 of 310) for patients who received placebo (P = .757). At 3 years, the IMA graft occlusion rate was 10.3% (8 of 78) for patients treated with aspirin compared with 7.9% (7 of 89) for patients who received placebo (P = .594). For IMA grafts that were patent at 1 year, the occlusion rate was 4.3% (3 of 70) for patients treated with aspirin compared with 2.5% (2 of 81) for patients who received placebo (P = .541).

CONCLUSIONS
These data suggest that aspirin treatment does not improve saphenous vein graft or IMA graft patency between 1 and 3 years after CABG.
Reconsideration of criteria for the Fontan operation. Influence of pulmonary artery size on postoperative hemodynamics of the Fontan operation.
Authors: Senzaki H , Isoda T , Ishizawa A , Hishi T 
Published: June 2012

BACKGROUND
The outcome of the Fontan operation largely depends on the selection of patients because this procedure is a physiological correction. Among the several selection criteria for the Fontan operation, the importance of adequate size of the pulmonary artery remains controversial. In this series, in order to clarify whether the pulmonary artery size is indispensable or not as one of the selection criteria for the Fontan operation, we considered the physiological meaning of pulmonary artery size and investigated how it influenced postoperative hemodynamics of the Fontan operation.

METHODS AND RESULTS
In congenital heart disease of decreasing pulmonary blood flow, 40 patients were examined for this analysis. Pulmonary artery indexes (cross-sectional area of the right and left pulmonary arteries divided by body surface area) were measured as the expression of pulmonary artery size, and the relations of pulmonary artery index (PAI) to pulmonary vascular resistance (Rp) and compliance (Cp) were studied. There was no significant correlation between PAI and Rp, whereas a significant correlation was found between PAI and Cp (r = .71, P = .001). Furthermore, Cp influenced postoperative hemodynamics of the Fontan operation by affecting the peak central venous pressure (pCVP) and total impedance, which was the afterload to the ventricle. Impedance increased abruptly when PAI was < approximately 100 mm2/m2.

CONCLUSIONS
The smaller pulmonary artery size causes more disadvantageous hemodynamics after the Fontan operation, with resultant effects of the rise in pCVP and the increase in afterload to the single ventricle.
Plasma angiotensin-converting enzyme activity and carotid wall thickening.
Authors: Bonithon-Kopp C , Ducimetière P , Touboul P J , Fève J M , Billaud E , Courbon D , Héraud V 
Published: June 2012

BACKGROUND
Mechanisms underlying the previously reported association between a deletion polymorphism in the gene encoding for angiotensin-converting enzyme (ACE) and the risk of myocardial infarction in low-risk subjects are unclear. The purpose of this case-control study was to examine the relation of plasma ACE activity to intimal-medial thickness of the carotid wall measured ultrasonographically in an apparently healthy population.

METHODS AND RESULTS
We determined plasma ACE activity in 80 pairs of subjects without any history of ischemic heart disease or any treatment of hypertension and diabetes. Cases and control subjects were defined on the basis of intimal-medial thickness measured in the common carotid arteries by B-mode ultrasound and were matched for sex, sonographer, and the presence of atheromatous plaques. Subjects were selected from a sample of 434 men and 602 women between 60 and 69 years old participating in an ongoing study on vascular aging (EVA). Subjects with intimal-medial thickening (cases) showed a slight but not significant increase in plasma ACE activity in comparison with control subjects (P < .16). However, after exclusion of subjects receiving lipid-lowering drugs, the mean plasma ACE activity became significantly higher in cases than in control subjects (29.9 +/- 7.7 U/L versus 27.5 +/- 8.0 U/L; n = 54 pairs, P < .03). The mean case-control difference in plasma ACE activity was further increased when analysis was restricted to pairs without carotid atheromatous plaques (n = 42 pairs). After adjustment for body mass index, smoking, and systolic blood pressure, the odds ratio for having carotid wall thickening based on 1 SD difference in log ACE was 2.29 (95% confidence interval, 1.16 to 4.52; P < .02).

CONCLUSIONS
The results of the study suggest that chronic exposure to high levels of plasma ACE could be involved in structural changes of the arterial wall.
Dyslipidemia and ischemic heart disease mortality among men and women with diabetes.
Authors: Goldschmid M G , Barrett-Connor E , Edelstein S L , Wingard D L , Cohn B A , Herman W H 
Published: June 2012

BACKGROUND
We investigated whether the greater increased risk of ischemic heart disease mortality associated with diabetes among women compared with men could be explained by their more pronounced lipoprotein abnormalities.

METHODS AND RESULTS
Seventy-six men and 45 women with diabetes and 327 men and 496 women without diabetes were followed for an average of 16 years in a population-based study. Cox proportional hazards models were used to determine the relative hazard of ischemic heart disease mortality for changes in lipoprotein subfractions after adjustment for age, hypertension, obesity, smoking, exercise, alcohol consumption, and estrogen use (among women). The relative hazard of ischemic heart disease mortality among diabetic women was 1.76 (P = .10) for a 10-mg/dL decrement in high-density lipoprotein cholesterol (HDL-C) and 3.13 (P = .01) for a 1-U increment in log very-low-density lipoprotein cholesterol (VLDL-C). The risk of ischemic heart disease mortality among diabetic women relative to nondiabetic women for an HDL-C level of 50 mg/dL and a log(e) VLDL-C of 3 (about 20 mg/dL) were 4.1 and 3.4, respectively (P < .05). These lipoprotein changes were not associated with ischemic heart disease mortality among men or among nondiabetic women.

CONCLUSIONS
Excess ischemic heart disease mortality among diabetic women is partially explained by deleterious levels of HDL-C and VLDL-C. HDL-C levels of < or = 50 mg/dL and VLDL-C levels of > or = 20 mg/dL appear to predict ischemic heart disease mortality among these women and may help identify women who would benefit most from intervention.
A pilot, early angiographic patency study using a direct thrombin inhibitor as adjunctive therapy to streptokinase in acute myocardial infarction.
Authors: Lidón R M , Théroux P , Lespérance J , Adelman B , Bonan R , Duval D , Lévesque J 
Published: June 2012

BACKGROUND
The success of streptokinase in acute myocardial infarction is hampered by the high failure rate to achieve early reperfusion. This study evaluates the possible benefit of Hirulog (Biogen, Cambridge, Mass), a direct thrombin inhibitor, as adjunct therapy to streptokinase to enhance early patency and prevent rethrombosis. Heparin has been shown to be of very limited benefits in this setting.

METHODS AND RESULTS
Forty-five patients were randomized to Hirulog or heparin (2:1 ratio). Coronary angiography documented a TIMI 2 or 3 flow after 90 minutes in 77% of the patients treated with Hirulog and streptokinase and in 47% of patients treated with heparin and streptokinase (P < .05) and after 120 minutes in 87% and 47% of patients, respectively (P < .01). TIMI 3 flow was established in 77% of patients with Hirulog compared with 40% with heparin (P < .02). The clinical outcome and the bleeding rate was also favorable to Hirulog; no reocclusion was observed at late angiography performed 4.7 days later.

CONCLUSIONS
Hirulog in this pilot study significantly improved the early patency rate of the infarct-related artery with a favorable clinical profile. This new direct thrombin inhibitor exhibits promise as adjunctive therapy to thrombolysis.
Dispersion of the QT interval. A marker of therapeutic efficacy in the idiopathic long QT syndrome.
Authors: Priori S G , Napolitano C , Diehl L , Schwartz P J 
Published: June 2012

BACKGROUND
QT interval dispersion, measured as interlead variability of QT, is a marker of dispersion of ventricular repolarization and, hence, of cardiac electrical instability. We tested the hypothesis that dispersion of ventricular repolarization may be differently affected by interventions destined to provide complete or incomplete protection against malignant arrhythmias in patients with long QT syndrome (LQTS). Twenty-eight patients affected by the Romano Ward form of LQTS entered the study and were divided into three groups: LQTS patients before institution of therapy, patients who did respond to beta-blocker therapy, and patients who continued to have syncope and cardiac arrest despite beta-blockade and who underwent left cardiac sympathetic denervation. A group of 15 healthy volunteers served as control subjects.

METHODS AND RESULTS
Dispersion of QT and QTc were calculated using two indexes: the difference between the longest and the shortest value measured in each of the 12 ECG leads (QTmax-QTmin, QTcmax-QTcmin) and the relative dispersion of QT and QTc (standard deviation of QT/QT average x100, standard deviation of QTc/QTc average x100). Both indexes of dispersion of repolarization were higher in the LQTS patients than in control subjects; also, patients not responding to beta-blockers had a significantly higher dispersion of repolarization than responders. A cutoff value of 100 milliseconds for QTmax-QTmin had an 80% sensitivity and 82% specificity in discriminating between responders and nonresponders. A cutoff value of 6 for QT relative dispersion yielded similar results. The LQTS patients who did not respond to beta-blockade underwent left cardiac sympathetic denervation and thereafter remained asymptomatic (mean follow-up, 5 +/- 4 years). In this group, dispersion of repolarization was significantly reduced by the surgical denervation to values similar to that of the responders to beta-blockade.

CONCLUSIONS
These data indicate that QT dispersion is a useful clinical tool to predict efficacy of antiadrenergic therapy in LQTS patients.
Comparison of intravascular ultrasound and angiography in the assessment of myocardial bridging.
Authors: Ge J , Erbel R , Rupprecht H J , Koch L , Kearney P , Görge G , Haude M , Meyer J 
Published: June 2012

BACKGROUND
In autopsy, myocardial bridging is a common finding. With coronary angiography, a systolic compression, mainly of the left anterior descending coronary artery, is observed in 1% to 3% of the patients. Controversy exists concerning the functional importance of this finding. To obtain a functional insight into the myocardial bridging, intravascular ultrasound and intracoronary Doppler were performed.

METHODS AND RESULTS
Intracoronary ultrasound and Doppler were performed in 14 patients with angiographic evidence of systolic vessel compression ("milking effect") in the left anterior descending coronary artery. The 4.8F, 20-MHz ultrasound catheter could not be advanced through the entire myocardial bridge segment in 6 of the 14 patients studied because the lumen was < 1.6 mm. In these patients, only the proximal parts of the bridge segment were scanned. The changes in cross-sectional shape during the cardiac cycle were determined for both the normal proximal segment and the bridge segment by use of a semiautomatic computer program. Intracoronary Doppler (20 MHz) was performed in 7 patients with a 3F catheter. A highly characteristic systolic eccentric or concentric compression with delayed relaxation in diastole of the myocardial bridging segment was clearly visualized in all patients. The cross-sectional lumen area variation was 40 +/- 25% in the bridging segments and 9 +/- 7% in the normal segments (P < .01). No atherosclerotic lesions were detected in the bridge or the distal segment in the 8 patients in whom the IVUS catheter was successfully advanced through the entire myocardial bridge. However, atherosclerotic plaques were found in the segments proximal to the bridge in 12 of 14 patients (86%). The resting mean flow velocity was 6.4 +/- 1.2 cm/s; the maximal mean flow velocity after intracoronary administration of 10 mg papaverine was 14.1 +/- 3.4 cm/s. The coronary flow velocity reserve was 2.2 +/- 0.7. A highly characteristic pattern showing a prominent peak in coronary velocity in early diastole was observed in 86% of patients, and this pattern was enhanced after injection of intracoronary papaverine.

CONCLUSION
Intravascular ultrasound demonstrated a characteristic systolic compression of the bridge segments. The delayed compression release may explain the characteristic sharp early diastolic peak in coronary flow velocity found with intracoronary Doppler in vessels with myocardial bridging. Reduced coronary flow reserve may be related to this phenomenon, possibly explaining signs of ischemia detected in some of the patients, but may alternatively be a result of the presence of atherosclerosis in the segment proximal to the bridge in these patients.