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Chaim Lotan

Publications and source records attributed to Chaim Lotan.

At least 19 recordsLinked to original sources
PubMed2006

Safety of coronary sirolimus-eluting stents in daily clinical practice: one-year follow-up of the e-Cypher registry.

BACKGROUND: The expanding indications for sirolimus-eluting stents (SES) include increasingly complex coronary lesions and populations with clinical profiles markedly different from those of early pivotal controlled studies. The e-Cypher registry monitored the safety and efficacy of SES currently implanted worldwide in daily practice. METHODS AND RESULTS: Between April 2002 and September 2005, data were collected on 15,157 patients who underwent implantation of > or =1 SES at 279 medical centers from 41 countries. An independent endpoint review committee adjudicated all reported major adverse cardiovascular events, stent thromboses, and target-vessel revascularizations. Data were managed and analyzed by independent organizations. Predictors of adverse clinical events were identified by regression analysis. The mean age of the sample was 61.7+/-11.4 years; 77.7% were men, and 28.6% were diabetics. A total of 18,295 lesions were treated (20,503 SES) during the index procedure. The cumulative rates of major adverse cardiovascular events were 1.36% at 30 days, 3.38% at 6 months, and 5.80% at 1 year. The rates of acute, subacute, and late stent thrombosis were 0.13%, 0.56%, and 0.19% of patients, respectively, representing a 12-month actuarial incidence of 0.87%. Insulin-dependent diabetes, acute coronary syndrome at presentation, and advanced age were clinical predictors, whereas TIMI flow grade <3 after the index procedure, treatment of multiple lesions, a prominently calcified or totally occluded target lesion, and multivessel disease were the angiographic or procedural predictors of stent thrombosis at 12 months. CONCLUSIONS: This analysis of 1-year data collected by the e-Cypher registry suggests a high degree of safety of SES, with a rate of stent thrombosis similar to that observed in randomized trials.

Aged↗
PubMed2006

Comparison of cardiovascular risk of noncardiac surgery following coronary angioplasty with versus without stenting.

Previous studies have shown a high incidence of cardiovascular complications when noncardiac surgery (NCS) is performed after coronary stenting. No study has compared the outcomes of NCS after stenting compared with percutaneous transluminal coronary angioplasty (PTCA) alone. The records of all patients who underwent NCS within 3 months of percutaneous coronary intervention at our institution were reviewed for adverse clinical events with the end points of acute myocardial infarction, major bleeding, and death < or = 6 months after NCS. A total of 216 consecutive patients were included in the study. Of these, 122 (56%) underwent PTCA and 94 (44%) underwent stenting. A total of 26 patients (12%) died, 13 in the stent group (14%) and 13 in the PTCA group (11%), a nonsignificant difference. The incidence of acute myocardial infarction and major bleeding was 7% and 16% in the stent group and 6% and 13% in the PTCA group (p = NS), respectively. Significantly more events occurred in the 2 groups when NCS was performed within 2 weeks of percutaneous coronary intervention. In conclusion, our study has demonstrated high rates of perioperative morbidity and mortality after NCS in patients undergoing PTCA alone, as well as stenting. These findings support the current guidelines regarding the risk of NCS after stenting but suggest they be extended to PTCA as well.

Age Factors↗
PubMed2006

In-hospital cardiac arrest: is outcome related to the time of arrest?

BACKGROUND: Whether outcome from in-hospital cardiopulmonary resuscitation (CPR) is poorer when it occurs during the night remains controversial. This study examined the relationship between CPR during the various hospital shifts and survival to discharge. METHODS: CPR attempts occurring in a tertiary hospital with a dedicated, certified resuscitation team were recorded prospectively (Utstein template guidelines) over 24 months. Medical records and patient characteristics were retrieved from patient admission files. RESULTS: Included were 174 in-hospital cardiac arrests; 43%, 32% and 25% in morning evening and night shifts, respectively. Shift populations were comparable in demographic and treatment related variables. Asystole (p < 0.01) and unwitnessed arrests (p = 0.05) were more common during the night. Survival to discharge was poorer following night shift CPR than following morning and evening shift CPR (p = 0.04). When asystole (being synonymous with death) was excluded from the analysis, the odds of survival to discharge was not higher for witnessed compared to unwitnessed arrest but was 4.9 times higher if the cardiac arrest did not occur during the night shift (p = 0.05, logistic regression). The relative risk of eventual in-hospital death for patients with return of spontaneous circulation (ROSC) following night shift resuscitation was 1.9 that of those with ROSC following morning or evening resuscitation (Cox regression). CONCLUSIONS: Although unwitnessed arrest is more prevalent during night shift, resuscitation during this shift is associated with poorer outcomes independently of witnessed status. Further research is required into the causes for the increased mortality observed after night shift resuscitation.

Aged↗
PubMed2006

Sirolimus-eluting stent in chronic total occlusion: the SICTO study.

Coronary stenting can significantly reduce the restenosis and reocclusion rates after successful balloon angioplasty for chronic total occlusions (CTO). Nevertheless, recanalization of CTO remains among the worst predictors for in-stent restenosis and reocclusion. This multicenter, nonrandomized study assessed the safety and effectiveness of the CYPHER sirolimus-eluting stent in reducing angiographic in-stent late loss in totally occluded native coronary arteries. A total of 25 eligible patients were treated with the CYPHER sirolimus-eluting stent. Baseline clinical and angiographic data were collected and 6-month follow-up angiography and intravascular ultrasound (IVUS) were performed. Clinical follow-up was required at 30 days, 6, 12, 18, and 24 months. Study stent implantation was successful in all patients, with a mean stent length of 28.4 +/- 11 mm. Six-month angiographic outcomes showed that mean lumen diameter stenosis did not change (2.22 +/- 0.56 mm postprocedure; 2.26 +/- 0.60 mm at 6 months follow-up; P = NS). Similarly, mean percent diameter stenosis did not change significantly (15.7 +/- 8.6% postprocedure, 19.3 +/- 11% at follow-up; P = NS). The absolute late lumen loss was -0.03 +/- 0.28 mm with a 6-month in-stent restenosis rate of 0%. IVUS follow-up revealed in-stent obstruction volume of only 4.9 +/- 6.8%. Long-term clinical follow-up showed target lesion revascularization at 12 months was only 4%, with target vessel revascularization of only 12%. The CYPHER sirolimus-eluting stent was safe and effective in the treatment of CTO compared to historical data with bare metal stents.

Aged↗
PubMed2006

Anti-erbB2 treatment induces cardiotoxicity by interfering with cell survival pathways.

INTRODUCTION: Cardiac dysfunction is among the serious side effects of therapy with recombinant humanized anti-erbB2 monoclonal antibody. The antibody blocks ErbB-2, a receptor tyrosine kinase and co-receptor for other members of the ErbB and epidermal growth factor families, which is over-expressed on the surface of many malignant cells. ErbB-2 and its ligands neuregulin and ErbB-3/ErbB-4 are involved in survival and growth of cardiomyocytes in both postnatal and adult hearts, and therefore the drug may interrupt the correct functioning of the ErbB-2 pathway. METHODS: The effect of the rat-anti-erbB2 monoclonal antibody B-10 was studied in spontaneously beating primary myocyte cultures from rat neonatal hearts. Gene expression was determined by RT-PCR (reverse transcription polymerase chain reaction) and by rat stress-specific microarray analysis, protein levels by Western blot, cell contractility by video motion analysis, calcium transients by the FURA fluorescent method, and apoptosis using the TUNEL (terminal uridine nick-end labelling) assay. RESULTS: B-10 treatment induces significant changes in expression of 24 out of 207 stress genes analyzed using the microarray technique. Protein levels of ErbB-2, ErbB-3, ErbB-4 and neuregulin decreased after 1 day. However, both transcription and protein levels of ErbB-4 and gp130 increased several fold. Calreticulin and calsequestrin were overexpressed after three days, inducing a decrease in calcium transients, thereby influencing cell contractility. Apoptosis was induced in 20% cells after 24 hours. CONCLUSION: Blocking ErbB-2 in cultured rat cardiomyocytes leads to changes that may influence the cell cycle and affects genes involved in heart functions. B-10 inhibits pro-survival pathways and reduces cellular contractility. Thus, it is conceivable that this process may impair the stress response of the heart.

Animals↗
PubMed2006

Paradoxical effects of aurintricarboxylic acid and RG-13577: acute thrombosis and in-stent stenosis in a passive-coated stent.

PURPOSE: To investigate if a platelet inhibitor (aurintricarboxylic acid [ATA]) and a heparin-mimicking antagonist (RG-13577) of basic fibroblast growth factor 2 (bFGF2) could be combined as a stable compound and attached to conventional bare metal stents to hinder thrombus formation and inflammatory reactions of stenting. METHODS: Fifteen domestic pigs were stented with RG-13577/ATA-coated (n=6), ATA-coated (n=12), and bare metal stents (n=12) in the left anterior descending (LAD) and left circumflex (LCX) coronary arteries. All surviving pigs were evaluated with contrast angiography and intravascular ultrasonography (IVUS) after 4 weeks. Histological analysis of the stented arteries was performed after hematoxylin-eosin staining. Tissue factor (TF) staining and scanning electron microscopy (SEM) were performed in animals with acute stent thrombosis. RESULTS: Five of the 6 animals receiving an RG-13577/ATA-coated stent experienced acute stent thrombosis, while no adverse events occurred in the animals of the other 2 groups. Follow-up angiography did not show significant in-stent stenosis in either bare or ATA-coated stents. However, histomorphometry revealed larger neointimal area (3.54+/-0.69 mm2 versus 1.82+/-0.27 mm2, p<0.05) and outward plaque area (1.56+/-0.34 mm2 versus 0.61+/-0.12 mm2, p<0.05) in ATA-coated stents. Three-dimensional IVUS analysis showed analogous results, with significantly larger neointimal volume and outward plaque volume in ATA-coated stents. There was a slight increase in TF staining around the stent struts, while SEM showed increased platelet adhesion and activity in RG-13577/ATA-coated stents versus the ATA-coated and bare metal stents. CONCLUSION: RG-13577/ATA-coated stents lead to acute stent thrombosis. The ATA coating alone did not lead to acute events, but resulted in higher neointimal hyperplasia and expansive remodeling. These results underline the importance of preclinical studies before using new coated stents in human arteries.

Animals↗
PubMed2005

The diagnostic value of troponin T testing in the community setting.

BACKGROUND: Many patients presenting with chest pain to their family physician are referred to the emergency room, in part, due to lack of accurate objective diagnostic tools. This study aimed to assess the diagnostic value of bedside troponin T kit testing in patients presenting with chest pain to their family physician. DESIGN: Prospective, multi-center study. METHODS: Consecutive subjects with chest pain were recruited from 44 community clinics in Jerusalem. Following clinical assessment by the family physician, qualitative troponin kit testing was performed. Patients with a negative clinical assessment and negative troponin kit were sent home and all others were referred to the emergency room. The final diagnosis at the time of hospital discharge was recorded and telephone follow up was performed after 60 days. Positive predictive value, negative predictive value, sensitivity and specificity of troponin kit for myocardial infarction diagnosis and of family physician for hospitalization, were assessed. RESULTS: Of 392 patients enrolled, 349 (89%) were included in the final analysis. The prevalence of myocardial infarction was 1.7%. The positive and negative predictive values of the troponin kit for myocardial infarction diagnosis were 100% and 99.7%, respectively. The positive and negative predictive values of the family physician's assessment to predict hospitalization were 41.4% and 94.1%, respectively. CONCLUSIONS: Troponin kit testing is an important tool to assist the family physician in the assessment of patients with chest pain in the community setting. Troponin kit testing may identify otherwise undiagnosed cases of myocardial infarctions, and reduce unnecessary referrals to the emergency room.

Ambulatory Care↗
PubMed2005

Use of polytetrafluoroethylene-covered stent for treatment of coronary artery aneurysm.

Coronary artery aneurysm is an uncommon occurrence, yet it is described more often today than in the past as coronary angiography is now routinely used for diagnosis and treatment of ischemic heart disease. However, there is no therapeutic consensus regarding this finding. We present a case of giant coronary artery aneurysm and review the literature on the use of polytetrafluoroethylene-covered stents as a therapeutic option for this condition. Combined antiaggregant therapy is needed after the procedure. Randomized controlled trials of surgery versus covered stents are necessary to define the best treatment for large coronary artery aneurysms.

Coated Materials, Biocompatible↗
PubMed2005

An Internet-based registry examining the efficacy of heparin coating in patients undergoing coronary stent implantation.

BACKGROUND: Heparin coating is an attractive alternative to counterbalance intrinsic stent thrombogenicity and to decrease the incidence of stent thrombosis. METHODS: We compared, based on the data of an international multicenter prospective registry, the rates of stent thrombosis after percutaneous coronary interventions in native coronary arteries using a Bx VELOCITY heparin-coated stent versus a bare metal stent of the same design in a total of 3098 patients at high risk for stent thrombosis. Most patients in both groups underwent percutaneous coronary intervention for unstable angina (48.4% vs 47.5%, respectively) with > 25% of the patients treated for acute myocardial infarction (30.8% and 28.1%, respectively). RESULTS: Procedural success was high and very similar in patients with heparin-coated and bare metal stents (99.3% vs 98.8%, respectively, P = .11). The primary end point, a 30-day stent thrombosis, occurred in 0.6% of the 1417 patients treated with the heparin-coated stent and 0.9% of the 1681 patients treated with the bare metal stent (relative risk reduction 33%, P = .41). The rates of cardiac death, myocardial infarction, and target lesion revascularization did not differ significantly between the groups. By multivariate analysis, variables independently associated with 30-day stent thrombosis included the evidence of thrombus at baseline (odds ratio [OR] 3.0, 95% CI 1.29-7.0, P = .01), small vessel stenting (OR 2.41, 95% CI 1.01-5.74, P = .05), and target left anterior descending artery (OR 2.32, 95% CI 1.00-5.38, P = .05). CONCLUSION: This large-scale registry comparing the use of heparin-coated stent versus bare metal stent in the reality of daily practice showed no significant difference in stent thrombosis in patients with a high-risk profile for thrombotic complications.

Angina, Unstable↗
PubMed2005

Future shock: automatic external defibrillators.

PURPOSE OF REVIEW: This review provides a practical overview of the performance capabilities of automatic external defibrillators (AEDs), and of advances in technology and dissemination programmes for these devices. RECENT FINDINGS: Arrhythmia analysis by AEDs is extremely reliable in most settings (sensitivity 81-100%, specificity 99.9-97.6%). Accurate detection of arrhythmias has also been demonstrated in children, leading the US Food and Drug Administration to approve the use of several AEDs in children aged 8 years or younger. Factors that potentially may reduce the quality of arrhythmia detection are the presence of wide complex supraventricular tachycardia and location of an arrythmic event near to high-power lines. AED use by professional basic life support providers resulted in increased survival in the prehospital setting. However, provision of AEDs to nonmedical rescue services did not result in universal improvement in patient outcome. Public access defibrillation programmes have led to higher rates of survival from cardiac arrest. The role of AEDs in hospitals has yet to be elucidated, although in-hospital mortality from ventricular arrhythmias has been shown to decrease following AED deployment. SUMMARY: Given the correct setting, AEDs can ensure that defibrillation is not limited by lack of medical knowledge or difficulties in decision making. However, event-related variables and operator-related factors, that are yet to be determined, can significantly affect the efficacy of automatic external defibrillation.

Journal Article↗
PubMed2005

Predictors for successful angioplasty of chronic totally occluded coronary arteries.

AIMS: Reevaluation of clinical and angiographic predictors for percutaneous recanalization of coronary chronic total occlusion (CTO) using current techniques with conventional PTCA wires and balloons. METHODS AND RESULTS: We studied 253 consecutive patients with 283 lesions who underwent attempted PTCA of CTO (mean time since occlusion 33 months, range 3-150 month). Immediate procedural success rate was 84.8% (95% CI = 80.3%-88.6%). Multiple clinical and angiographic characteristics were evaluated as possible predictors of success/failure. Multiple logistic regression analysis revealed that a tapered morphology (P < 0.001, OR = 6.1; 95% CI = 2.1-18.2), </=45 degree of angulations of the target artery (P < 0.03, OR = 4.5; 95% CI = 1.2-17.2), length of occlusion <15 mm (P < 0.001, OR = 3.4; 95% CI = 1.6-7.0), and the presence of multiple lesions in the target artery (P < 0.03, OR = 2.2; 95% CI = 1.1-4.4) were statistically significant independent predictors of procedural success. According to absence or presence of the various identified determinants of outcome, predicted procedural success rates varied between 26 and 98%. CONCLUSIONS: Although the probability of immediate procedural success with percutaneous recanalization of coronary CTO using conventional PTCA is now high, a number of characteristics of the occlusive lesion represent significant modulators of success or failure. These factors should be utilized in the process of patients or lesions selection.

Angioplasty, Balloon, Coronary↗
PubMed2005

[Surgical intervention in infective endocarditis: indications and timing].

A major advance has occurred over recent decades in the treatment strategies for infective endocarditis (IE). A significant part of this progress is due to a clearer knowledge of IE insult patterns; especially those concerning valvular damage and resultant heart failure. Furthermore, the existence of IE unique vegetations ensuring a suitable platform for organism growth and partial antibiotic resistance, has led to an understanding of the limited capacity of antibiotics to treat IE. Accordingly, an increased emphasis on surgical intervention has emerged. Indeed, the last decades were characterized by increased attempts to explore the feasibility and efficacy of surgical approach in IE. The present review is a result of these attempts, summarizing the major indications for surgical intervention in IE, as was recently published by the American Heart Association. Generally, such intervention is warranted in IE complications including: hemodynamically significant valvular damage, paravalvular abscess, continuous infection despite optimal treatment, recurrent emboli and antibiotic-resistant organisms. Recognition of the prognostic influence of pre-treatment heart failure degree has led to the development of early surgical intervention, namely, surgical intervention during the active period of IE. Application of such early intervention has led to survival rates which are significantly higher than achieved by antibiotic treatment per se.

Cardiac Surgical Procedures↗
PubMed2004

Distal protection of bifurcating vessels: a novel approach.

Distal protection devices protect only a single distal vessel. We describe a novel technique to protect both branches following a thrombus-containing bifurcation lesion. The combination of an occlusive balloon and an arterial filter system provides an attractive solution to the challenging environment of a lesion at high risk for distal embolization supplying more than a single major branch.

Angioplasty, Balloon, Coronary↗
PubMed2003

Comparison of bypass surgery and stenting for the treatment of multivessel disease: results from the ARTS trial in Israel.

BACKGROUND: The Arterial Revascularization Therapies Study was a multicenter, randomized trial designed to compare percutaneous coronary intervention with stenting versus coronary artery bypass graft surgery in 1,205 patients with multivessel coronary artery disease. The most appropriate type of treatment for these patients is still a matter of considerable debate. OBJECTIVES: To evaluate the clinical characteristics of patients enrolled in the ARTS trial in Israel in comparison to those worldwide, and to assess the 1 year outcome in these patients. METHODS: Between April 1997 and June 1998, a total of 1,205 patients with multivessel coronary artery disease, who were considered to be equally treatable with both modalities, were randomized to either stenting (n = 600) or CABG (n = 605) at 67 centers around the world. In Israel, 53 patients at four participating medical centers were randomized to either PCI with stents (n = 27) or CABG (n = 26). RESULTS: Clinical and angiographic characteristics were similar in the two groups, except for a significantly higher incidence of diabetic patients in Israel who were randomized to CABG, compared to those worldwide (35% vs. 16%, P = 0.01). Also, there were more patients with unstable angina in Israel (63 vs. 37%, P = 0.006). At 1 year follow-up, overall mortality and cerebrovascular accident rates were similar between the two groups and equivalent to results obtained around the world. There was a significantly higher incidence of myocardial infarction rates in patients randomized to stenting in Israel compared to patients worldwide (7.4 vs. 5.3%, P = 0.01) or to patients randomized to CABG in Israel (7.4 vs. 0%, P = 0.006). Similar to the overall ARTS results, there was a higher incidence of repeat revascularization procedures in patients assigned to the PCI with stenting arm (22.2 vs. 3.8%, P = 0.004) compared to those randomized to CABG, respectively. CONCLUSIONS: The results of this analysis of the Israeli ARTS population indicate that coronary stenting and bypass surgery yield similar findings with regard to mortality and stroke and are comparable to those obtained in the whole study group. Likewise, coronary stenting was associated with an increased incidence of repeat revascularization procedures as compared to CABG. However, patients in Israel randomized to stenting had a higher rate of myocardial infarction as compared to the overall results and to patients who underwent CABG in Israel. The present analysis provides important data for the safety and efficacy of either stenting or bypass surgery in treating patients with multivessel disease in Israel.

Angioplasty, Balloon, Coronary↗
PubMed2003

Clinical manifestations and outcome of acute myocardial infarction in very young patients.

BACKGROUND: Acute myocardial infarction is rare in people under the age of 30. OBJECTIVE: To determine the clinical features and outcome in young patients presenting with AMI. METHODS: All patients aged 30 years and younger hospitalized with AMI during a period of 8 years (1993-2000) were evaluated for clinical features and outcome. RESULTS: Of the 3,758 patients with AMI, 15 were 30 years old or younger (0.4%). The mean age was 28 (range 21-30 years) and all were male. Eight had normal coronary arteries on angiogram; seven had obstructive coronary artery disease. Patients with OCA had more classical risk factors for coronary disease. A complete diagnostic workup was abnormal in four patients with NCA: thrombophilia in two patients, spasm due to alcohol withdrawal and hyperthyroidism in one patient each. All patients presented with typical new-onset chest pain. None had a previous history of angina. All patients with OCA received reperfusion therapy as compared to one patient with NCA. Peak creatine phosphokinase in NCA and OCA was 504 +/- 547 and 1,328 +/- 440 respectively (P < 0.01). All patients with NCA had good left ventricular function on follow-up echocardiography, compared to only three in the OCA group (P = 0.02). There was one death due to cardiogenic shock in a patient with OCA. Follow-up of 4 +/- 2 years demonstrated recurrent acute coronary syndromes in four of seven patients with OCA versus none in the NCA patients (P = 0.02). CONCLUSIONS: AMI is rare in very young patients, and more than half NCA. A thrombophilic tendency or spasm should be considered. Young patients with NCA have an excellent prognosis.

Adult↗
PubMed2002

Effects of the superoxide dismutase-mimetic compound tempol on endothelial dysfunction in streptozotocin-induced diabetic rats.

Evidence exists to support the beneficial effects of superoxide dismutase on endothelial dysfunction induced by hyperglycemia in vitro. In vivo, however, studies of the effects of native superoxide dismutase preparations on the vascular complications accompanying diabetes are limited, and their therapeutic application potential has so far been disappointing. The objective of this study was to evaluate, for the first time in vivo, the effects of long-term administration of tempol, a stable superoxide dismutase-mimic compound, on diabetes-induced endothelial dysfunction in rats. Diabetes was induced by streptozotocin and rats were monitored for 8 weeks with or without treatment with tempol (100 mg/kg, s.c., b.i.d). Diabetic rats showed increased vascular levels of superoxide, which was accompanied by increased levels of the oxidative stress markers malondialdehyde and 8-epi-prostaglandin F(2alpha). In addition, the vasorelaxant as well as the cGMP-producing effects of acetylcholine and glyceryl trinitrate were reduced in diabetic rats. Treatment with tempol abolished not only the differences in the vascular content of superoxide, malondialdehyde and 8-epi-prostaglandin F(2alpha), but also the differences in the relaxation and cGMP responses of aortic rings to both acetylcholine and glyceryl trinitrate between control and diabetic rats. These results support the involvement of reactive oxygen species in mediation of hyperglycemia-induced endothelial dysfunction in vivo, and provide the rationale for potential utilization of stable superoxide dismutase-mimic nitroxides for the prevention of the vascular complications accompanying diabetes.

Acetylcholine↗