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Ran Kornowski

Publications and source records attributed to Ran Kornowski.

At least 19 recordsLinked to original sources
PubMed2004

Anterior wall myocardial infarction in real world: does reperfusion strategy make any differences?

Some prospective randomized trials have established the superiority of primary percutaneous coronary intervention (PCI) over fibrinolytic treatment in patients with acute myocardial infarction (MI). These excellent PCI results are not duplicated in smaller hospitals where there may be delays in getting the cardiac catheterization team to the laboratory. This study aimed to compare the outcome of patients with anterior wall MI, without cardiogenic shock on admission, treated with primary PCI or thrombolytic therapy, in everyday practice. The data of all patients with MI hospitalized in all coronary care units operating in Israel during three consecutive national surveys was analyzed. A total of 1,038 patients with anterior wall MI were treated by reperfusion (886 received thrombolytic therapy, 152 primary PCI). Overall, the outcome of patients treated using primary PCI was better compared to patients treated with thrombolysis, with 68% relative risk reduction of 30-day mortality (mortality at 30 days: 2% vs. 6.3%; P = 0.04). A subanalysis of patients according to age showed that the beneficial effect of primary PCI on mortality was mainly clustered among the younger. In our study, patients (especially younger than 75 years) with anterior wall MI allocated to primary PCI have a better clinical outcome.

Age Factors↗
PubMed2003

Degrees of severe stenoses in sigma-shaped versus C-shaped right coronary arteries.

The right coronary artery (RCA) appears either C-shaped or sigma-shaped during standard angiography. The purpose of the present investigation was to assess whether C-shaped RCAs are associated with more atherosclerotic disease than sigma-shaped RCAs. The study sample comprised 120 consecutive patients who underwent coronary catheterization and multivariate analysis was conducted using several systemic risk factors for atherosclerosis. The proportion of sigma-shaped RCAs found in a group whose angiograms showed little or no obstruction (70%) was significantly higher than that found in the group with significant obstruction (33%, p <0.001). In conclusion, a C-shaped RCA is associated with atherosclerosis.

Adult↗
PubMed2003

Catheter-based autologous bone marrow myocardial injection in no-option patients with advanced coronary artery disease: a feasibility study.

OBJECTIVES: We conducted a pilot study to evaluate the feasibility of transendocardial delivery of autologous bone marrow (ABM) strategy in patients with severe symptomatic chronic myocardial ischemia not amenable to conventional revascularization. BACKGROUND: Transendocardial injection of ABM cells appears to enhance perfusion of ischemic porcine myocardium. METHODS: Ten patients underwent transendocardial injection of freshly aspirated and filtered unfractionated ABM using left ventricular electromechanical guidance. Twelve injections of 0.2 ml each were successfully delivered into ischemic noninfarcted myocardium pre-identified by single-photon emission computed tomography perfusion imaging. RESULTS: Autologous bone marrow injection was successful in all patients and was associated with no serious adverse effects; in particular, there was no arrhythmia, evidence of infection, myocardial inflammation, or increased scar formation. Two patients were readmitted for recurrent chest pain. At three months, Canadian Cardiovascular Society angina score significantly improved (3.1 +/- 0.3 vs. 2.0 +/- 0.94, p = 0.001), as well as stress-induced ischemia occurring within the injected territories (2.1 +/- 0.8 vs. 1.6 +/- 0.8, p < 0.001). Treadmill exercise duration, available in nine patients, increased, but the change was not significant (391 +/- 155 vs. 485 +/- 198, p = 0.11). CONCLUSIONS: This study provides preliminary clinical data indicating feasibility of catheter-based transendocardial delivery of ABM to ischemic myocardium.

Bone Marrow Transplantation↗
PubMed2003

Preliminary experiences using X-sizer catheter for mechanical thrombectomy of thrombus-containing lesions during acute coronary syndromes.

Thrombus-containing lesions are frequently observed in patients with acute coronary syndromes. These lesions are prone to increased procedural risks, including distal embolization and abrupt closure of the vessel. This preliminary report evaluates if thrombus removal using a new X-Sizer catheter could reduce thrombotic burden and optimize angioplasty results. Thrombectomy was attempted with the X-Sizer catheter in 11 patients (age, 59 +/- 10 years) undergoing coronary angioplasty with angiographic evidence of intracoronary thrombus. The device uses a helix cutter contained in a 4.5 or 5.5 Fr catheter tip connected to a closed vacuum aspiration system. Procedural outcomes using detailed angiographic analysis and clinical data were obtained from all treated patients. Seven patients (64%) had acute or recent myocardial infarction and four patients (36%) presented with unstable angina. The culprit lesion was located in right coronary, left anterior, vein graft, and circumflex-marginal in five, three, two, and one patient, respectively. The mean proximal reference diameter was 3.37 +/- 0.39 mm and % diameter stenosis was 90% +/- 15% prior to thrombectomy and decreased to 72% +/- 16% afterward and was 9% +/- 10% at the end of the procedure. The TIMI flow increased from 0.8 +/- 1.0 to 2.1 +/- 0.9 following thrombectomy and the final TIMI grade was 2.9 +/- 0.3. Stents were used in 9 of 11 patients. Procedural success was achieved in 10 of 11 patients (91%). No evidence of stent thrombosis was noted among treated patients in hospital and at 30-day follow-up. In this preliminary series of patients with angiographic evidence of thrombus, the use of X-Sizer thrombectomy seems to be feasible and relatively safe, permitting thrombus removal and improved intracoronary flow.

Aged↗
PubMed2003

Autologous stem cells for functional myocardial repair.

Recent experimental studies based on innovative hypothesis utilizing cell therapy for the damaged myocardium are recently becoming increasingly promising. The naturally occurring myocardial reparative process is apparently complex and relatively inefficient. It consists of up-regulation of progenitor cell release from the bone marrow after myocardial infarction, homing of these cells to the injured tissue, and differentiation of these progenitor cells into vascular cells and cardiomyocytes within the infarcted tissue. Accordingly, there are two main strategies to regenerate myocardium with autologous stem cells: (1) Extracting stem cells from the bone marrow and injecting these cells into the damaged area, (2) Increasing the efficiency of the naturally occurring reparative process by increasing the mobilization of bone marrow-derived stem cells after myocardial infarction. This review summarizes the growing field of autologous stem cell utilization over the past decade and outlines scientific and clinical hurdles that need to be overcome before this therapy can fully reach its clinical potential.

Heart Failure↗
PubMed2003

Acute and intermediate-term results of percutaneous coronary stenting in octogenarian patients.

BACKGROUND: Percutaneous coronary intervention (PCI) in octogenarian patients has been associated with increased cardiovascular morbidity and mortality. This study aimed to assess acute and intermediate-term clinical outcomes among octogenarians undergoing PCI. METHODS: The authors identified 97 consecutive patients aged > or =80 years who underwent PCI using stents between November 2000 and February 2002 at their institution. The patients were divided into three groups according to clinical presentation: (1) acute myocardial infarction (AMI, n = 31); (2) unstable angina pectoris (UAP, n = 28); and (3) stable angina pectoris (SAP, n = 38). Procedural data, and in-hospital and six-month clinical outcomes were obtained and adjudicated for all patients. RESULTS: Overall mean age was 84 +/- 3 years, 67% of patients were males and 73% had multivessel coronary disease. In-hospital outcomes varied according to clinical presentation: procedural success was 78% in AMI patients (including shock patients), 93% in UAP, and 95% in SAP patients. Likewise, hospital mortality was 26% in AMI, 3.6% in UAP, and 0% in SAP patients (p = 0.0003). Among AMI patients, hospital mortality was extremely high in patients with cardiogenic shock (67% versus 4.6% in AMI without shock, p < 0.0001). Cumulative event rate at six months also varied according to clinical presentation: mortality/MI and target vessel revascularization (TVR) rates were 29%, 3.6%, and 0% in AMI, 7.1%, 7.4%, and 11% in UAP and 0%, 5.3%, and 7.9% in SAP patients. Multivariate analysis identified cardiogenic shock as the most powerful risk factor for predicting mortality (odds ratio = 42, p = 0.03). CONCLUSIONS: These results show that clinically stable octogenarian patients undergoing PCI have favorable procedural and intermediate-term prognosis. In contrast, cardiogenic shock has a profound negative prognostic impact on octogenarians despite 'aggressive' PCI attempts.

Acute Disease↗
PubMed2003

Collateral formation and clinical variables in obstructive coronary artery disease: the influence of hypercholesterolemia and diabetes mellitus.

BACKGROUND: Collateral circulation is severely compromised in patients who have a limited degree of spontaneous myocardial angiogenesis and arteriogenesis. METHOD: To determine the clinical characteristics associated with angiographic apparent collaterals (AAC) and myocardial blush score (MBS), this study compared the clinical variables in various AAC and MBS grades (0 = no, 1 = minimal, 2 = moderate and 3 = maximal collaterals defined by the two variables) among a consecutive group of 112 patients (aged 62 +/- 12 years, 76% men) with a native artery chronic total coronary occlusion studied by selective coronary angiograms. RESULTS: By univariate analysis, including variables such as age, sex, diabetes, hypertension, hypercholesterolemia, smoking and ejection fraction, the only variable that was found more frequently in patients with greater AAC grade was hypercholesterolemia (59%, 63%, 71% and 78% in patients with AAC grade 0, 1, 2 and 3, P = 0.003). Ejection fraction tended to be more preserved in patients with greater AAC score (46%, 48%, 51% and 54% in patients with AAC grade 0, 1, 2 and 3, respectively, P = 0.052). Diabetes mellitus was the only factor that was negatively associated with MBS (23%, 22%, 18% and 16% in patients with MBS grade 0, 1, 2 and 3, P = 0.01). Using a multivariate logistic regression analysis to predict maximal AAC grade, the only independent predictor found was hypercholesterolemia (odds ratio = 1.3, confidence limits = 1.05-1.9, P = 0.048). Diabetes mellitus was the only predictor found to be negatively associated with MBS (odds ratio = 0.72, confidence limits = 0.46-0.98, P = 0.04). It is concluded that collateral grade is associated with hypercholesterolemia and myocardial blush is negatively associated with diabetes mellitus. These findings may reflect a conflicting impact of hypercolesterolemia and diabetes mellitus upon collateral formation, leading to enhanced or depressed angiogenesis in response to obstructive coronary artery disease.

Aged↗
PubMed2003

Validation of vital signs recorded via a new telecare system.

A telecare system (Medic4All) has been developed that relies on a wireless wristwatch-like sensor to measure the pulse wave from the radial artery. From this, the heart rate and respiration rate are derived. The system's performance was examined by comparing the results obtained from the pulse wave signal with those obtained from conventional electrocardiographic and spirometer devices. A total of 144 patients participated in the study; their mean (SD) age was 43 (18) years. There were 44 cardiac patients in group 1 and 100 healthy patients, who were studied in their homes, in group 2. There was a significant correlation between the heart rates measured by the two monitoring methods. A 'difference versus average' analysis showed that the error distribution had a mean (SD) value of -0.1 (3.3) beats/min. Similarly, the respiration rates measured by the two techniques were significantly correlated. The error distribution had a mean (SD) value of 0.1 (1.9) respirations/min. The present study suggests that the wrist-worn sensor represents a promising tool for online detection and monitoring of vital signs in the home.

Adult↗
PubMed2002

Stroke complicating percutaneous coronary interventions: incidence, predictors, and prognostic implications.

BACKGROUND: Stroke associated with percutaneous coronary intervention (PCI) is an infrequent although devastating complication. We investigated the incidence, predictors, and prognostic impact of periprocedural stroke in unselected patients undergoing PCI. METHODS AND RESULTS: A total of 9662 patients who underwent 12 407 PCIs between January 1990 and July 1999 were retrospectively studied. Stroke was diagnosed in 43 patients (0.38% of procedures). Patients with stroke were older (72+/-11 versus 64+/-11 years, P<0.001), had lower left ventricular ejection fraction (42+/-12 versus 46+/-13%, P=0.04) and more diabetes (39.5% versus 27.2%, P=0.07), and experienced a higher rate of intraprocedural complications necessitating emergency use of intra-aortic balloon pump (IABP) (23.3% versus 3.3%, P<0.001). In-hospital mortality (37.2% versus 1.1%, P<0.001) and 1-year mortality (56.1% versus 6.5%, P<0.001) were higher in patients with stroke. Compared with hemorrhagic stroke, patients with ischemic stroke had higher rate of in-hospital major adverse cardiac events (57.1% versus 25%, P=0.037). Multivariate logistic regression analysis identified emergency use of IABP as the strongest predictors for stroke (OR=9.6, CI 3.9 to 23.9, P<0.001), followed by prophylactic use of IABP (OR=5.1), age >80 years (OR=3.2, compared with age <50 years), and vein graft intervention (OR=2.7). CONCLUSIONS: Stroke associated with contemporary PCI is associated with substantial increased mortality. Elderly patients who experience intraprocedural complications necessitating the use of IABP are at particularly high risk.

Aged↗
PubMed2002

Safety and efficacy of a 6 French perclose arterial suturing device following percutaneous coronary interventions: a pilot evaluation.

BACKGROUND: Arterial access site management after percutaneous coronary intervention (PCI) is a matter of increasing importance in this era of potent antiplatelet pharmacotherapy. We evaluated the safety and efficacy of a 6 French (Fr) Perclose suturing device in achieving rapid hemostasis of the access site after PCI and thus improving patient comfort. METHODS: The 6 Fr Perclose (Prostar) device consists of a suture-based closure device delivered via introducer sheath designed for suturing of the arteriotomy puncture site. Over a 3-month period, the device was used in 48 consecutive PCI treated patients (age, 62 13 years; 70% male; 44% post myocardial infarction) and in-hospital groin complication rate was compared to 48 consecutive patients (age, 64 12 years; 64% male; 33% post myocardial infarction) who had manual compression hemostasis. RESULTS: Antiplatelet glycoprotein IIb/IIIa antagonists were used more frequently during and following the procedure in 58% of Perclose-treated patients versus 42% of the manual compression group (p = 0.019). Leg immobilization duration was 3 4 hours in all patients sutured by the device; in patients with manual compression, the sheath was removed at an average of 4.8 2.5 hours after termination of the PCI and an additional 6 hours of leg immobilization were subsequently required. No difference in overall major complication rate was found between groups (6.2% in suture-mediated patients versus 9.3% in manual compression group; p = 0.60). In 3 patients (6.2%) treated using the device, adjunctive manual compression was required in addition to groin suturing due to technical failure or residual oozing from the arteriotomy site. CONCLUSION: The 6 Fr Perclose device can be safely used to achieve rapid hemostasis and the device may hasten bed mobilization of PCI-treated patients despite frequent use of potent antiplatelet pharmacotherapy during coronary interventions.

Adult↗
PubMed2001

Anti-angiogenesis: A new potential strategy to inhibit restenosis.

Microvessels are an integral component of the neointima developing in response to the acute vascular injury resulting from angioplasty. These vessels originate from the vasa vasorum of the adventitia, and as such appear similar to the microvessels present in atherosclerotic plaques. Several angiogenic factors have been found in atherosclerotic plaques and have been associated with increased microvascularity. In addition, most of these agents - either directly or indirectly - also induce smooth muscle cell (SMC) proliferation, an essential component of the developing neointima. We therefore propose: (1) these newly formed blood vessels are necessary for the development, maintenance, and expansion of the neointimal lesions present in restenosis; (2) the initiation, regulation and maintenance of these vessels is, at least in part, due to the coordinate sequential expression of hypoxia-inducible factor 1 (HIF-1), vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), and/or other angiogenic factors such as the fibroblast growth factor (FGF) family of proteins; (3) targeted disruption of the signal transduction pathways modulated by these molecules may reduce vasa vasorum expansion and SMC proliferation. These effects, in turn, may inhibit neointimal expansion and thus the development of restenosis, especially following stenting.

Journal Article↗
PubMed2001

Percutaneous Approach to Achieve Therapeutic Myocardial Angiogenesis.

Myocardial therapeutic angiogenesis is a novel approach for treating the large number of patients with advanced symptomatic coronary artery disease not amenable to conventional revascularization approaches. Proof of concept has been demonstrated in animal models of myocardial ischemia, and preliminary results suggest possible benefit in clinical trials of direct surgical (transepicardial) delivery of proteins and recombinant genes encoding angiogenic growth factors. Catheter-based intramyocardial gene delivery strategies have been tested in parallel, with the assumption that the less invasive nature and the potential for multiple treatment sessions would make this technique more applicable. Currently, most of the data relating to the catheter-based transendocardial delivery of angiogensis factors are derived from the experience with a single device (Biosense; Johnson & Johnson, Skillman, NJ). Using this injection platform, catheter-based gene delivery was demonstrated in animals to be safe and feasible, with a transfection yield similar to that achieved by the direct transepicardial approach. At the time of this review, more than 45 patients have been enrolled in Phase I clinical trials that evaluate the safety and feasibility of transendocardial delivery of adenovirus and plasmid-mediated gene transfection as well as cellular elements.

Journal Article↗
PubMed2000

Catheter-based transendocardial gene delivery for therapeutic myocardial angiogenesis.

Currently it is unknown which is the most effective and safest delivery strategy for therapeutic myocardial angiogenesis. The enhancing effect of direct intramyocardial injection of angiogenic factors using either open-chest or catheter-based approaches on collateral function has been reported to occur in experimental models and among patients. This report reviews the rationale and current experience of using a catheter-based approach as a promising platform for proangiogenic intramyocardial gene delivery strategy.

Journal Article↗
PubMed1999

Intravascular ultrasound observations of atherosclerotic lesion formation and restenosis in patients with diabetes mellitus.

Coronary artery disease is more aggressive in diabetic patients than in nondiabetics; they have more diffuse disease, higher mortality rates and worse clinical outcomes after coronary interventions. Intravascular ultrasound (IVUS) produces transmural tomographic images of the coronary arteries in vivo. Recent IVUS studies have provided new insights into the mechanisms of stenosis formation and restenosis in both nondiabetic and diabetic patients. Arterial remodeling is defined as a change in arterial area. During atherogenesis, an increase in arterial area usually accompanies plaque accumulation to delay lumen compromise. Stenosis formation is related to: (a) the rate of plaque accumulation versus the rate of positive remodeling; and (b) the limits and ultimate failure of positive remodeling. However, there is a marked variability in remodeling. IVUS studies have suggested that remodeling may be impaired in some diabetic patients during atherogenesis. Following non-stent catheter-based interventions, serial (post-intervention and follow-up) IVUS studies have shown that the change in lumen area correlates better with the change in arterial area (remodeling) than with the change in plaque area (neointimal hyperplasia). In some patients, a positive remodeling response mitigates against the increase in plaque area to limit late lumen loss and restenosis. Neointimal hyperplasia is exaggerated in diabetic patients. Despite this, there is a reduced frequency of positive remodeling, potentially similar to the impaired positive remodeling in some diabetic patients during atherogenesis. Failed or inadequate arterial remodeling may contribute to the pathogenesis and natural history of atherosclerotic coronary artery disease in diabetic patients.

Journal Article↗