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Pramod Kuchulakanti

Publications and source records attributed to Pramod Kuchulakanti.

17 recordsLinked to original sources
PubMed2005

Three-year follow-up after intravascular gamma-radiation for in-stent restenosis in saphenous vein grafts.

The Washington Radiation for In-Stent Restenosis Trial in Saphenous Vein Grafts (SVG WRIST) demonstrated safety and efficacy of intravascular radiation therapy (IRT) for the treatment of in-stent restenosis (ISR) in SVG at 12 months. In this study, we aimed to examine whether the safety and efficacy of IRT is durable up to 36 months. One hundred twenty patients with diffuse ISR in SVG underwent balloon angioplasty, laser or atherectomy ablation, and/or additional stenting. After successful intervention, patients were randomly assigned in a double-blind fashion to intravascular treatment with a ribbon containing either iridium (Ir)-192 (n = 60) or nonradioactive seeds (n = 60). The prescribed dose at 2 mm from the source was either 14 or 15 Gy in vessels 2.5-4.0 mm or 18 Gy in vessels > 4.0 mm in diameter. At 36 months, target lesion revascularization (TLR; 43% vs. 66%; P = 0.02) and target lesion revascularization-major adverse cardiac event (TLR-MACE; 49% vs. 71%; P = 0.02) rates continued to be lower in the IRT group, but both target vessel revascularization (TVR; 59% vs. 71%; P = 0.17) and TVR-MACE (63% vs. 77%; P = 0.11) rates were not. In SVG WRIST, patients with ISR treated with IRT had a marked reduction in the need for repeat TLR at 36 months, with sustained clinical benefit at 3 years despite late recurrences, which were more pronounced in the radiation group.

Aged↗
PubMed2005

Brachytherapy and bivalirudin evaluation study.

BACKGROUND: Bivalirudin is shown to be a competent substitute for heparin in percutaneous coronary intervention (PCI). The safety and efficacy of bivalirudin in patients undergoing PCI and vascular brachytherapy (VBT) are not known. This study aimed to assess the safety and efficacy of bivalirudin as a single antithrombotic agent in patients undergoing PCI and VBT. METHODS: A total of 152 patients enrolled in the Brachytherapy and Bivalirudin Evaluation Study underwent PCI and VBT with either gamma (n = 8) or beta radiation (n = 144). The main outcome measures were in-hospital events and 30-day clinical outcomes. All patients were treated with bivalirudin (0.75 mg/kg bolus and 1.75 mg/kg per hour infusion for beta radiation, 1 mg/kg bolus and 2.5 mg/kg per hour infusion for gamma radiation) as a single antithrombotic agent during the entire procedure. RESULTS: Baseline clinical and angiographic characteristics were similar between the 2 groups. More than 90% of the patients received beta radiation. In-hospital events showed a higher prevalence of acute procedural intracoronary thrombosis in patients treated with gamma- vs beta radiation (25% vs. 0.7%, P < .001). Thirty-day outcomes including death, Q-wave, and non-Q-wave myocardial infarctions, subacute stent thromboses, and repeat revascularizations were similar in both groups. CONCLUSION: Bivalirudin, as a single antithrombotic agent during PCI and VBT with beta emitters, may be used safely, but its use in the setting of PCI and gamma radiation may not be acceptable due to an increased incidence of acute procedural intracoronary thrombosis.

Angioplasty, Balloon, Coronary↗
PubMed2005

Impact of continued hospitalization in patients pre-treated with clopidogrel prior to coronary angiography and undergoing coronary artery bypass grafting.

Pre-treatment of patients with clopidogrel prior to coronary angiography (CAG) and possible percutaneous coronary intervention (PCI) is a standard practice. Candidates for coronary artery bypass surgery (CABG) are discharged or remain in the hospital until CABG after clopidogrel is discontinued. We investigated whether any differences exist in the rates of surgical complications and outcomes between these two groups of patients. We conclude that continued hospitalization of clopidogrel pre-treated patients does not confer any safety benefit with regard to post-operative complications and 30-day mortality. Discharging these patients after CAG may reduce hospitalization costs.

Aged↗
PubMed2004

Oral rapamycin to inhibit restenosis after stenting of de novo coronary lesions: the Oral Rapamune to Inhibit Restenosis (ORBIT) study.

OBJECTIVES: The aim of this study was to establish safety and feasibility of oral Rapamycin at two doses-2 mg and 5 mg-in achieving low rates of repeat target lesion revascularization (TLR) in de novo native coronary artery lesions. BACKGROUND: Drug-eluting stents have shown the ability to limit restenosis. Oral Rapamycin is an alternative strategy that can target multiple coronary lesions suitable for treatment with any approved metal stent and at potentially lower cost. METHODS: The Oral Rapamune to Inhibit Restenosis (ORBIT) study is an open-label study of 60 patients with de novo lesions treated with bare metal stents in up to two vessels. After a loading dose of 5 mg, patients received a daily dose of 2 mg (n = 30) and 5 mg (n = 30) for 30 days. Six-month angiographic, intravascular ultrasound (IVUS), and clinical follow-up were conducted. RESULTS: Baseline clinical and procedural characteristics were similar: 10% of patients in the 2-mg group and 30% in the 5-mg group did not complete the course; 43% in the 2-mg group and 66% in the 5-mg group had side effects. At six-month follow-up, late loss (0.6 +/- 0.5 mm vs. 0.7 +/- 0.5 mm; p = NS), in-stent binary restenosis (7.1% vs. 6.9%; p = NS), in-stent percent volume obstruction by IVUS (29% vs. 24%; p = NS), and clinically driven TLR (14.3% vs. 6.9%; p = NS) were similar in 2-mg and 5-mg groups. CONCLUSIONS: Oral Rapamycin for the prevention of restenosis is safe, feasible, and associated with low rates of repeat revascularization. Although associated with certain side effects, it may be considered for patients undergoing multivessel stents if proven in larger randomized studies.

Administration, Oral↗
PubMed2004

Impact of major side branch on periprocedural enzyme elevation and long-term outcome in patients undergoing percutaneous coronary intervention and brachytherapy for in-stent restenosis.

Side branch occlusion is 1 mechanism for the increase of creatine phosphokinase-MB after percutaneous coronary intervention and is associated with long-term adverse events. We studied 248 patients who underwent brachytherapy for in-stent restenosis with and without side branches, compared levels of creatine phosphokinase-MB with procedural, in-hospital, and long-term clinical outcomes, and found that patients with side branches have increased levels of creatine phosphokinase-MB after percutaneous coronary intervention and higher rates of restenosis, target vessel, and target lesion revascularization at 6-month follow-up.

Angioplasty, Balloon, Coronary↗
PubMed2004

Therapeutic potential of oral antiproliferative agents in the prevention of coronary restenosis.

The treatment of coronary artery disease has reached many milestones - from balloon angioplasty to drug-eluting stents. The last decade witnessed the revolution of bare metal stents with new designs, alloys and strut thicknesses. Yet restenosis, the aphorismic 'Achilles heel', remains to be conquered. The restenosis rates with balloon angioplasty alone are 30-40% and are reduced to 20-30% with stents. Although intravascular brachytherapy proved to be a durable and safely used technique to treat in-stent restenosis, clinical event rates were not reduced to single digits.Drug-eluting stents are showing positive results in this direction, but it is too early to predict their efficacy in various subsets of lesions. With the increased usage of these stents, there are reports of problems such as late stent malapposition, subacute and late thromboses, and aneurysm formations due to the vessel toxicity associated with this method of treatment. Furthermore, when multivessel stenting is considered, the cost of drug-eluting stents is a significant problem given the fact that these are no longer 'zero restenosis' devices. There is a definite need for a simple, safe and durable solution to restenosis. Oral agents are an alternative delivery strategy that can target multiple coronary lesions, which are targets for catheter-based revascularisation with any approved metal stent and with potentially lower cost. Although oral agents have been an interesting option to treat restenosis and several agents have been tested in trials since the 1980s, the results were disappointing. The development of devices such as intravascular ultrasound has led to a greater understanding of restenosis mechanisms, and the focus on pathophysiological mechanisms, which centred mainly on platelets, growth factors and lipids, has changed to inflammation, endothelium and smooth muscle cell proliferation.Accordingly, the targets of pharmaceutical agents have shifted from platelets to cell cycle inhibition, smooth muscle cell proliferation and migration, synthesis of extra cellular matrix, and inflammatory mediators. Initial encouraging results with oral drugs such as cilostazol, sirolimus (rapamycin) and thiazolidinediones indicate a definite place for this strategy to reduce restenosis. A desirable oral agent would be anti-inflammatory, inhibit smooth muscle cell migration and proliferation, promote endothelial growth, and be well tolerated and free from significant adverse effects. It may be useful to start with a high loading dose before stent implantation and then follow with a short-term lower maintenance dose. Future trials should be aimed at finding an ideal agent, effective loading dose, maintenance dose and optimum duration of therapy.

Administration, Oral↗
PubMed2004

Safety of percutaneous coronary intervention alone in symptomatic patients with moderate and severe valvular aortic stenosis and coexisting coronary artery disease: analysis of results in 56 patients.

Whether percutaneous coronary intervention (PCI) alone is safe in patients with moderate or severe aortic stenosis (AS) and coexisting coronary artery disease (CAD), and whether aortic valve replacement (AVR) can be deferred in patients with moderate AS by undergoing PCI alone is not known. We conducted a retrospective study of surgically inoperable patients with AS who underwent PCI (moderate AS, n = 28; and severe AS, n = 28) and compared to those with AVR (n = 55). The clinical characteristics, procedural complications, in-hospital and long-term clinical outcomes of PCI were compared. Baseline and procedural characteristics were similar except that lower age, hypertension, and renal impairment were seen in the AVR group. In-hospital complications were comparable among the 3 groups. Six-month and 1-year rates of myocardial infarction (MI), non-Q-wave MI, death and out-of-hospital death were similar between AVR and moderate AS patients (p = NS) and significantly high (p < 0.04) in patients with severe AS. On multivariate analysis, severe AS was the only significant predictor of 6-month and 1-year mortality. Our study suggests that PCI is safe in patients with moderate AS and coexisting CAD but is associated with poor outcomes in patients with severe AS.

Aged↗
PubMed2003

Mechanisms and methods to resolve edge effect.

Vascular brachytherapy (VBT) has established itself as a viable modality to treat in-stent restenosis (ISR). The problems associated with VBT have been understood well and remedied. Late thrombosis has been overcome to a great extent by prolonged antiplatelet therapy. Edge effect is another important limitation of VBT and is due to inadequate radiation coverage of the edges following VBT. It may be overcome by confining injury to the lesion segment and extending the radiation sources by a few millimeters from the injured segment.

Aged↗
PubMed2003

Repeat radiation for recurrent in-stent restenosis in patients who failed initial brachytherapy.

In-stent restenosis (ISR) is due to neointimal hyperplasia and is shown to be effectively inhibited by vascular brachytherapy (VBT). Despite its efficacy, 20-25% of patients present with recurrent ISR following failed initial VBT. Although conventional percutaneous coronary intervention (PCI) is offered in a majority of patients to treat failed brachytherapy, the requirement for repeat revascularization is about 50%. PCI with repeat radiation to treat this difficult subset of patients is safe and feasible with target lesion revascularization (TLR) rates less than 25%. The lessons learned from randomized trials of brachytherapy, including prevention of edge effect, prolonged antiplatelet therapy and the prescription of a higher mean dose, should be applied to treat these patients with repeat radiation.

Brachytherapy↗
PubMedDate not supplied

Peroxisome proliferator-activated receptor gamma: its role in metabolic syndrome.

Here we review PPARgamma function in relation to human adipogenesis, insulin sensitization, lipid metabolism, blood pressure regulation and prothrombotic state to perhaps provide justification for this nuclear receptor remaining a key therapeutic target for the continuing development of agents to treat human metabolic syndrome.

Adipose Tissue↗
PubMedDate not supplied

Optimizing dosimetry with high-dose intracoronary gamma radiation (21 Gy) for patients with diffuse in-stent restenosis.

BACKGROUND: The efficacy of intracoronary gamma radiation (IRT-gamma) in reducing recurrent in-stent restenosis (ISR) is well established using doses of 14-18 Gy. We sought to examine whether an escalation in dose to 21 Gy is safe and confers additional benefit in reducing repeat revascularization and major adverse cardiac events (MACE) in patients with diffuse ISR. METHODS: Forty-seven patients with diffuse ISR (lesion length 20-80 mm) in native coronary arteries (n=25) and saphenous vein grafts (n=22) underwent percutaneous transluminal coronary angioplasty and/or additional stents followed by IRT-gamma using the Checkmate system (Cordis) with a dose of 21 Gy. All patients were discharged with clopidogrel for 12 months and aspirin indefinitely. Six-month angiographic and 12-month clinical outcomes of these patients were compared to 120 patients treated with 18 Gy using the same system. RESULTS: At baseline, patients in the 21-Gy group had more multivessel, vein graft disease and history of prior myocardial infarctions and coronary artery bypass grafts (P<.001). The use of debulking devices and stents was less in this group (P<.001). Procedural and in-hospital complications were similar. Follow-up at 6 months revealed nonsignificant but lower late loss (in-stent, 0.33+/-0.7 mm; in-lesion, 0.41+/-0.6 mm) in the 21-Gy group compared to the 18-Gy group; follow-up at 12 months revealed a trend toward less overall myocardial infarction, although repeat revascularization and MACE rates were similar. CONCLUSIONS: IRT-gamma therapy for diffuse ISR lesions with a 21-Gy dose is clinically safe and feasible with marked reduction in late loss but does not confer additional benefit with regard to repeat revascularization and MACE when compared to a dose of 18 Gy.

Adult↗
PubMedDate not supplied

Bivalirudin compared with IIb/IIIa inhibitors in patients with in-stent restenosis undergoing intracoronary brachytherapy.

BACKGROUND: Bivalirudin is replacing heparin in percutaneous coronary interventions (PCIs), including vascular brachytherapy (VBT). The aim of the study was to compare bivalirudin with eptifibatide in patients with in-stent restenosis (ISR) undergoing PCI and VBT. METHODS: One hundred forty-four patients treated with bivalirudin as a single antithrombotic agent were compared with 150 patients treated with eptifibatide. Bivalirudin as a bolus of 0.75 mg/kg followed by 1.75 mg/kg/h infusion until the end of the procedure, and eptifibatide as a double bolus of 180 microg/kg followed by 2 microg/kg/min infusion for 18 h after the procedure were used. The main outcome measures were in-hospital events and 30-day clinical outcomes. RESULTS: Baseline clinical characteristics were similar except that patients in the eptifibatide group were younger (P=.02) and had more saphenous vein graft lesions (P<.001). Patients in the bivalirudin group had a higher number of lesions in the right coronary artery (P<.001) and a higher number of vessels treated (P<.001). Postprocedure creatinine phosphokinase (CPK)-MB levels were significantly lower in the bivalirudin group (P<.03). In-hospital events showed significantly less minor bleeding (P=.01) and a trend toward lower major bleeding and major adverse cardiac events (MACE) in the bivalirudin group (P=.06). Thirty-day outcomes showed a significantly lower incidence of non-Q-wave myocardial infarction (MI) in the bivalirudin group (P=.004). CONCLUSION: Bivalirudin, as a single antithrombotic agent during PCI and VBT, is associated with significantly lower postprocedural CPK-MB elevation, minor bleeding complications, 30-day non-Q-wave MI rates, and a trend toward lower major bleeding and in-hospital MACE when compared with eptifibatide.

Anticoagulants↗