Biomedical subjects

Kenneth M Kent

Publications and source records attributed to Kenneth M Kent.

At least 37 records · Page 2Linked to original sources

PubMed2006

Sirolimus-eluting stents and calcified coronary lesions: clinical outcomes of patients treated with and without rotational atherectomy.

This study examined the outcomes of patients who underwent sirolimus-eluting stent (SES) implantation for the treatment of heavily calcified coronary lesions (HCCL) with and without the use of rotational atherectomy (rotablator). We investigated 150 consecutive patients with angiographic evidence of HCCL who underwent SES implantation. Sixty-nine patients underwent SES implantation without the need of rotablator (SES), and 81 patients required rotational atherectomy to modify the plaque and facilitate the delivery of the stent (SES + rotational atherectomy). Clinical success was equivalent in both groups (>98%) and there were no in-hospital outcome differences. At 6 months, the target lesion revascularization rate was 4.9% in SES vs. 4.2% in SES + rotational atherectomy groups, respectively (P = NS). Mortality at 6 months was 7.9% in the SES group vs. 6.8% in the SES + rotational atherectomy group (P = NS). SES performs well in patients with complex HCCL, with a relative low event rate. Lesions requiring rotational atherectomy to facilitate dilation and stenting had similar outcomes after SES implantation to those that could be stented without the need for rotablator.

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PubMed2006

Impact of overlapping drug-eluting stents in patients undergoing percutaneous coronary intervention.

BACKGROUND: Sirolimus-eluting stent (SES) implantation for the treatment of single coronary lesions is proven to be effective and durable. However, the safety and efficacy of overlapping SES for the treatment of long lesions have not been well established. OBJECTIVES: We conducted a retrospective analysis to compare the clinical outcomes of overlapping versus nonoverlapping SES. METHODS: Fifty-five patients who received overlapping SES were compared with 39 patients who received nonoverlapping SES. RESULTS: The baseline clinical and angiographic characteristics were balanced between the two study groups. The in-hospital complications were similar between groups, except that non-Q-wave myocardial infarction was significantly higher in the Overlapping SES group when compared with the Nonoverlapping SES group (23.6% vs. 7.7%, P = 0.04). This higher rate of myonecrosis is due to periprocedural side branch compromises, including side branch narrowing, occlusion, and flow reduction. At 30 days and 6 months follow-up, all clinical outcomes were similar between the study groups. In addition, the event-free survival rate was similar between groups (P = 0.87). CONCLUSIONS: The implantation of overlapping SES for the treatment of long, native coronary lesions is feasible and effective but is associated with an increased rate of periprocedural myonecrosis. This phenomenon is caused primarily by side branch compromises, but does not have any adverse impact on late clinical events.

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PubMed2006

Impact of three or more sirolimus-eluting stents versus paclitaxel-eluting stents on clinical outcomes in patients undergoing percutaneous coronary intervention.

OBJECTIVES: The purpose of this study was to examine the clinical outcomes of patients who underwent stenting with > or =3 sirolimus-eluting stents (SES) when compared with those treated with > or =3 paclitaxel-eluting stents (PES). BACKGROUND: Drug-eluting stent (DES) implantation for single coronary lesions is proven to be effective and durable. METHODS: A total of 126 patients who received DES were identified, of which 66 patients received > or =3 SES (SES group) and 60 patients received > or =3 PES (PES group). RESULTS: The baseline clinical and angiographic characteristics were compatible between the two study groups. During the index hospitalization, all clinical outcomes were similar between the two groups. There were no deaths or Q-wave myocardial infarctions (MIs) in either group. At 30 days' and 6 months' follow-up, all clinical outcomes, including death, Q-wave MI, non-Q-wave MI, target lesion revascularization, target vascular revascularization, and major adverse cardiac events, were compatible between both groups. There were 2 patients (3.0%) with subacute thrombosis in the SES group and 1 patient (1.7%) in the PES group, but there was no statistical significance. There was no late thrombosis from either group. In addition, patients in the SES group had similar event-free survival rates as compared with those in the PES group (P = 0.56). CONCLUSIONS: Patients who require > or =3 DES implantations experienced increased adverse clinical events as compared with historical single stent implantation. However, there were no differences in safety and efficacy among the patients treated with SES as compared with those treated with PES.

Angioplasty, Balloon, Coronary↗

PubMed2006

Percutaneous coronary intervention with drug-eluting stents in octogenarians: characteristics, clinical presentation, and outcomes.

OBJECTIVES: We aimed to compare clinical outcomes of octogenarians > or =80 years of age after coronary drug-eluting stent (DES) implantation. BACKGROUND: Although octogenarians constitute a fast-growing portion of cardiovascular patients, they are not adequately represented in current clinical revascularization trials. METHODS: We analyzed the data of 3,166 consecutive patients who underwent percutaneous coronary intervention (PCI) and DES implantation since March 2003. Periprocedural events, 1- and 6-month clinical outcomes were compared between octogenarians (n = 339) and patients <80 years of age (n = 2,827). RESULTS: Baseline characteristics revealed a higher prevalence of females (P < 0.001), Caucasians (P = 0.004), chronic renal failure (P < 0.001), heart failure (P < 0.001), number of diseased vessels (P = 0.009), and lower ejection fraction (P = 0.03) in octogenarians. Patients <80 years showed more positive family history (P < 0.001), hyperlipidemia (P = 0.006), smoking (P < 0.001), and obesity (P < 0.001). Clinical presentation and procedural success were similar in both groups as were death, myocardial infarction (MI), and repeat revascularization in-hospital. At 6 months, restenosis rates were low and comparable. In the subgroup of octogenarians who presented with acute coronary syndrome, mortality (15% vs. 3%, P < 0.001) and Q-wave MI occurred more often. Multivariate analysis revealed age >80 (P = 0.008), cardiogenic shock (P < 0.001), Q-wave MI at presentation (P = 0.003), and length of hospital stay (P = 0.003) to be independent predictors of mortality. CONCLUSIONS: PCI with DES in octogenarians results in a similar reduction of restenosis rates when compared to patients <80 years. Yet in octogenarians who presented with acute coronary syndrome, incidence of mortality and Q-wave MI at 6 months was higher as compared to younger patients.

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PubMed2006

The impact of cardiovascular risk factors on subclinical left main coronary artery disease: an intravascular ultrasound study.

BACKGROUND: The impact of cardiovascular risk factors on subclinical but measurable left main coronary artery (LMCA) atherosclerosis is not well known. METHODS: We analyzed 150 consecutive patients with first-time coronary artery disease presentation undergoing intervention of a left anterior descending coronary artery or left circumflex lesion with motorized intravascular ultrasound transducer pullback that included a nonstenotic LMCA. Framingham, PROCAM, and European SCORE risk assessments were determined in 107 patients <65 years of age (because the Framingham, PROCAM, and European SCORE studies excluded patients >65 years old). Intravascular ultrasound measurements were compared in patients with <10% vs 10% to 20% risk of events. RESULTS: Plaque volumes were greater in patients with higher risk scores: P = .007 in patients with 10% to 20% PROCAM risk, P = .063 in patients with 10% to 20% Framingham risk, and P = .059 in patients with 10% to 20% SCORE risk (P = .059). The mean arc of LMCA calcium (12 degrees +/- 25 degrees overall) correlated with plaque volume (51 +/- 28 mm3, r = 0.30, P = .0001) and with the number of coronary risk factors (P = .048) and ranged from 0.28 degrees +/- 0.74 degrees in patients with 0 to 1 risk factors to 9.95 degrees +/- 21.55 degrees in patients with 2 to 4 risk factors to 19.38 degrees +/- 32.51 degrees in patients with 5 to 7 risk factors. Regression analysis showed obesity and age were the most important factors contributing to LMCA calcium. CONCLUSION: Intravascular ultrasound measurable atherosclerosis in nonstenotic LMCA correlates with conventional primary coronary risk scores. Left main coronary artery calcium correlates both with LMCA plaque volume and risk factors. Thus, subclinical LMCA atherosclerosis may be a marker for events that are predicted by commonly used primary risk-assessment algorithms.

Aging↗

PubMed2006

Efficacy of sirolimus-eluting stents as compared to paclitaxel-eluting stents for saphenous vein graft intervention.

BACKGROUND: Saphenous vein graft (SVG) intervention is associated with a significantly increased rate of periprocedural complications and late clinical and angiographic restenosis. In the contemporary drug-eluting stent (DES) era, the comparison of the efficacy of sirolimus-eluting stents (SES) with paclitaxel-eluting stents (PES) in SVG interventions is currently unknown. We conducted this retrospective analysis to investigate this issue. METHODS AND RESULTS: Forty-seven patients with 50 SVG lesions who underwent standard percutaneous coronary intervention (PCI) with SES (SES group) were compared with 42 patients with 45 SVG lesions with PES (PES group). All patients received distal protection devices (DPDs) during the interventions. The in-hospital, 30-day, and 6-month clinical outcomes in both groups were compared. Baseline clinical and procedural characteristics were balanced between both groups except for the proximal and mid lesions. There were no deaths or Q-wave myocardial infarctions (MIs) during the index hospitalization. Non-Q-wave MI was similar between the two groups (SES vs PES, 4.3% vs 7.1%, P=0.55). At 30-day and 6-month follow-ups, all the clinical outcomes were similar between the two groups. There was no subacute thrombosis (SAT) or late thrombosis in either group. The event-free survival at 6 months was also similar between both groups (P=0.75). CONCLUSIONS: The use of DES in patients undergoing SVG intervention with a DPD is clinically safe and feasible. As compared to SES, PES have the same efficacy and clinical outcomes in SVG interventions up to 6 months.

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PubMed2006

Clinical outcomes after percutaneous coronary intervention with drug-eluting stents in dialysis patients.

OBJECTIVES: We aimed to compare the clinical outcomes of dialysis versus nondialysis patients after coronary drug-eluting stent (DES) implantation. BACKGROUND: The revascularization of ischemic heart disease in dialysis patients has remained controversial due to consistent exclusion of this population from major trials, especially in the context of percutaneous coronary interventions (PCI) with DES. METHODS: We analyzed the data on 3,442 consecutive patients who underwent PCI and DES implantation since March 2003. Periprocedural events, 1- and 6-month clinical outcomes were then compared between dialysis (n = 72) and nondialysis patients (n = 3,370). RESULTS: Baseline characteristics revealed a higher prevalence of female gender (p = 0.03), African Americans (p < 0.001), hypertension (p < 0.001), diabetes mellitus (p < 0.001), number of diseased vessels (p = 0.04), lower ejection fraction (p < 0.001), and a higher prevalence of acute myocardial infarction (MI) (p = 0.04) in dialysis patients. Nondialysis patients showed more history of smoking (p < 0.001) and obesity (p = 0.02). Procedural success was higher (p = 0.05), while there was a trend toward a lower mortality rate, in the nondialysis group during hospitalization. At 6 months, the restenosis rate was low and comparable, but mortality occurred more often (16% vs. 3.8%; p < 0.001) in dialysis patients. Multivariate analysis revealed cardiogenic shock (p = 0.04) to be an independent predictor of mortality. CONCLUSIONS: PCI with DES in dialysis patients is safe and feasible, with a similar reduction of repeat revascularization when compared with nondialysis patients. There was, however, a higher incidence of mortality in dialysis patients at 6 months, mostly influenced by contributing comorbidities and more severe conditions at presentation.

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PubMed2006

Switching from Enoxaparin to Bivalirudin in Patients with Acute Coronary Syndromes without ST-segment Elevation who Undergo Percutaneous Coronary Intervention. Results from SWITCH--a multicenter clinical trial.

BACKGROUND: Enoxaparin is an established therapy for the treatment of patients with acute coronary syndrome (ACS), and bivalirudin is commonly used as the antithrombotic agent during percutaneous coronary intervention (PCI). This study was designed to examine the safety of switching from enoxaparin to bivalirudin in these patients. METHODS: The Switching from Enoxaparin to Bivalirudin in Patients with Acute Coronary Syndromes without ST-segment Elevation Undergoing Percutaneous Coronary Intervention (SWITCH) trial was a prospective, open-label, multicenter study including 91 patients who presented with an ACS without ST-segment elevation, and who had received greater than or equal to 1 dose of enoxaparin (1 mg/kg SC) within the 12 hours prior to PCI. Patients were enrolled into 3 time categories: Group 1: 0-4; Group 2: 4-8; and Group 3: 8-12 hours from last enoxaparin dose to PCI. The primary endpoint of the study was major bleeding complications. RESULTS: Baseline characteristics and average number of enoxaparin injections prior to PCI were similar in all 91 patients and among the groups. There was no occurrence of death, Q-wave myocardial infarction (MI), or acute revascularization in any group and no incidence of intracranial or retroperitoneal bleeding. The overall rate of major bleeding (7.7%) was comparable among groups (p = 0.39), as was the incidence of periprocedural non-Q-wave MI (overall 12%; p = 0.58), irrespective of the time interval between enoxaparin and bivalirudin administration. CONCLUSIONS: Switching from enoxaparin to bivalirudin for patients with ACS undergoing PCI appears to be clinically safe without increased risk of major bleeding complications, regardless of the time of enoxaparin administration, and is safe enough to warrant testing it in larger numbers.

Acute Disease↗

PubMed2005

Efficacy of sirolimus-eluting stents compared with bare metal stents for saphenous vein graft intervention.

Saphenous vein graft (SVG) intervention is associated with a significantly increased rate of periprocedural complications and late clinical and angiographic restenosis. We examined the efficacy and safety of sirolimus-eluting stents (SESs; Cypher) compared with bare metal stents (BMSs) in SVG intervention. Forty-eight patients who had 50 SVG lesions and underwent standard percutaneous coronary intervention with SESs (SES group) were compared with 57 patients who had 64 SVG lesions and underwent intervention with BMSs (BMS group). All patients received distal protection devices during SVG intervention. In-hospital, 30-day, 6-month, and 1-year clinical outcomes in the 2 groups were compared. Baseline clinical and procedural characteristics were balanced between groups. There were no deaths or Q-wave myocardial infarctions during the index hospitalization, but compared with the BMS group, patients in the SES group had significantly fewer non-Q-wave myocardial infarctions (4% vs 21%, p = 0.01), which was mainly attributed to increased periprocedural creatine kinase-MB levels. At 30-day, 6-month, and 1-year follow-ups, all clinical outcomes were similar between groups. Event-free survival at 1 year was also similar between groups (p = 0.84). In conclusion, the use of SESs in patients who undergo SVG intervention with a distal protection device is clinically safe and feasible but is not associated with decreased clinical events up to 1 year compared with BMSs.

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PubMed2005

Cardiovascular events in patients with coronary plaque rupture and nonsignificant stenosis.

The long-term outcome of patients who present with an identified plaque rupture in a nonflow-limiting lesion is not well known. We retrospectively studied 17 consecutive patients in whom intravascular ultrasound identified plaque rupture in nonflow-limiting lesions (minimum lumen area >4.0 mm2) that were not treated with coronary intervention. After a mean follow-up of 43 +/- 25 months, events related to those lesions were 1 death (6%) of undetermined cause (6%) that occurred after 69 months, no myocardial infarction, and 2 revascularizations (12%) that occurred at 3 and 67 months. Overall, the cumulative rate of cardiac events was 18%.

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PubMed2005

Impact of renal function on coronary plaque morphology and morphometry in patients with chronic renal insufficiency as determined by intravascular ultrasound volumetric analysis.

The aim of the present study was to use intravascular ultrasonography (IVUS) to assess plaque morphology and morphometry in patients with varying degrees of chronic renal insufficiency, including end-stage renal disease (ESRD) on dialysis replacement. Cardiovascular disease is the main cause of death for patients with chronic renal insufficiency, particularly in patients with ESRD. The impact of several degrees of renal insufficiency (including ESRD) on coronary plaque characteristics has not been determined. A total of 142 patients who underwent IVUS imaging of a de novo native coronary artery stenosis before percutaneous intervention were matched for age, gender, and diabetes and were grouped according to calculated creatinine clearance (CrCl): CrCl >70 ml/min (n = 39); CrCl 50 to 69 ml/min (n = 41); CrCl <50 ml/min, (n = 37), and ESRD (n = 25). Standard clinical, angiographic, and IVUS parameters were measured. The ESRD group had more African-American (p = 0.002) and hypertensive (p = 0.002) patients. No significant difference was found in any of the IVUS measurements among patients with CrCl >70, 50 to 69, and <50 ml/min: reference and lesion site arterial, lumen, and plaque areas and volumes, and arterial calcium (p = NS for all comparisons). Conversely, patients with ESRD had larger reference segment arterial and lumen areas and volumes; larger lesion site arterial, lumen, and plaque areas; and larger arcs of calcium (p <0.05 for all post hoc comparisons between patients with ESRD and patients with CrCl >70, 50 to 69, and <50 ml/min). Thus, chronic renal insufficiency in the absence of dialysis is not associated with increased reference segment or lesion site plaque burden and calcium. However, the transition to the need for dialysis is associated with progressive calcific atherosclerosis (larger lesion plaque area and calcium).

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PubMed2005

Serial intravascular ultrasound comparison of the extent and distribution of intimal hyperplasia six months after stent implantation for de novo versus in-stent restenosis lesions.

The aim of this study was to compare intimal hyperplasia (IH) growth at 6 months in patients with de novo lesions treated with stents versus IH regrowth in patients with treated in-stent restenosis. Intravascular ultrasound was performed after intervention and at the 6-month follow-up visit as part of a standardized protocol across several clinical trials. At 6 months, the lumen was larger in the de novo group (mean lumen cross-sectional area [CSA] 6.31 +/- 2.2 vs 4.48 +/- 1.9 mm(2), p = 0.0001; minimum lumen CSA 4.2 +/- 1.8 vs 2.59 +/- 1.5 mm(2), p = 0.0001). However, the total increase in the mean IH CSA volume was the similar in the de novo and ISR groups (2.89 +/- 1.6 vs 2.64 +/- 1.94 mm(2), respectively; p = 0.11). We found that IH regrowth in restented in-stent restenosis lesions was similar to that in de novo stent implantation and that the final lumen CSA was an important component of in-stent restenosis recurrence.

Coronary Restenosis↗

PubMed2005

Impact of treatment of coronary artery disease with sirolimus-eluting stents on outcomes of diabetic and nondiabetic patients.

Patients with diabetes mellitus are at increased risk for repeat interventions and mortality after coronary angioplasty and stenting. The efficacy of sirolimus-eluting stents (SESs) to improve the outcomes of these patients is a focus of interest. In the first 1,407 patients treated with SESs at our institution, 492 were diabetic (insulin dependent diabetes mellitus [IDDM], n = 160 and non-insulin-dependent DM [NIDDM], n = 332). The in-hospital and 1- and 6-month clinical outcomes were compared with those of 915 patients without DM (non-DM). The baseline characteristics were similar, except for more women, obesity, previous myocardial infarction, coronary artery bypass grafting, and renal insufficiency in the DM group (p <0.001). Compared with non-DM patients, DM patients had higher in-hospital (p <0.05) and 1-month mortality (p = 0.02). IDDM patients had more in-hospital renal failure (p = 0.04) and Q-wave myocardial infarctions (1.6% vs 0%, p = 0.04) compared with NIDDM patients, and higher mortality (3.1% vs 0.8%, p = 0.04) and subacute stent thromboses (2.3% vs 0.5%, p = 0.07) than non-DM patients at 30 days. At 6 months, DM patients had a higher incidence of Q-wave myocardial infarction, target lesion revascularization-major adverse cardiac events, and composite of death and Q-wave myocardial infarction than non-DM patients (6.0% vs 2.7%, p = 0.01). Late outcomes between the IDDM and NIDDM groups were similar. Multivariate analysis showed diabetes and acute renal failure as independent predictors of target lesion revascularization-major adverse cardiac events. In conclusion, our data showed that, despite a reduction in repeat revascularization, coronary intervention with SESs in diabetic patients is limited by higher mortality at 1 month and a higher incidence of Q-wave myocardial infarction and target lesion revascularization-major adverse cardiac events at 6 months compared with non-DM patients. Careful surveillance is required in IDDM patients undergoing SES implantation.

Angioplasty, Balloon, Coronary↗

PubMed2005

Bivalirudin versus heparin as an antithrombotic agent in patients who undergo percutaneous saphenous vein graft intervention with a distal protection device.

Bivalirudin (Angiomax) is increasingly used as a substitute for heparin in a variety of percutaneous coronary interventions, and data on its usage in saphenous vein graft interventions are limited. This retrospective, observational study evaluated the efficacy and safety of bivalirudin compared with heparin as an antithrombotic regimen in patients who underwent saphenous vein graft intervention with distal protection devices. We found that bivalirudin use is clinically safe and feasible, with fewer vascular and ischemic complications compared with heparin.

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PubMed2005

Incidence, location, magnitude, and clinical correlates of saphenous vein graft calcification: an intravascular ultrasound and angiographic study.

BACKGROUND: The pattern of saphenous vein graft (SVG) calcification before percutaneous intervention has not been studied. METHODS AND RESULTS: We used diagnostic and preintervention intravascular ultrasound (IVUS) to determine the incidence and magnitude of SVG calcification in 334 SVG lesions in 274 consecutive patients. Calcium was found in 133 SVGs (40%). Calcium was uniformly distributed among 48 lesion sites (14%), 43 proximal references (13%), and 42 distal references (13%). Calcium was superficial in 20 (40%) and deep in 28 (60%). Over the entire length of the SVGs, the maximum arc and length of calcium (in calcium-containing SVGs) averaged 174+/-107 degrees and 6.8+/-4.8 mm, respectively. In calcium-containing SVGs, lesion site arc and length of calcium measured 151+/-107 degrees and 4.1+/-3.7 mm, similar to the proximal and distal references (175+/-121 degrees and 4.0+/-2.3 mm and 177+/-121 degrees and 4.1+/-2.5 mm, respectively). Graft age (7.5+/-4.7 versus 10.5+/-4.7 years, P<0.0001), insulin-treated diabetes mellitus (40% versus 60%, P=0.02), and tobacco use (44% versus 55%, P=0.06) were clinical independent predictors of SVG calcification. CONCLUSIONS: Sixty-five percent of calcium-containing SVGs had reference calcium in the absence of lesion calcium. Calcium was located primarily in SVG wall and not at the plaque. These data suggest that SVG calcium is not just part of lesion formation and maturation. SVG calcium occurred more commonly in older grafts, in insulin-treated diabetic patients, and in smokers.

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PubMed2005

Real-world clinical practice of intracoronary radiation therapy as compared to investigational trials.

Intracoronary radiation therapy (IRT) is well established in clinical practice as an effective treatment for in-stent restenosis. We aimed to determine if the 6-month clinical outcome of patients treated postapproval for marketing [commercial radiation (CR)] is equivalent to those patients enrolled in the Washington Radiation for In-Stent Restenosis Trials [Gamma WRIST and Beta WRIST; investigational radiation (IR)]. The 6-month clinical outcome of 110 consecutive patients with 125 lesions who received IRT (gamma, (192)Ir, 15-18 Gy, n = 6; or beta, (32)P, 20 Gy, n = 20; or (90)Sr/Y, 18.4-23.0 Gy, n = 99) in CR was compared with the 6-month clinical outcome of 117 patients with 117 lesions who received IRT ((192)Ir, 15 Gy, n = 65, in Gamma WRIST; and (90)Y, 20.6 Gy, n = 52, in Beta WRIST) in IR. Patients in CR were treated with wider radiation margins. The CR received antiplatelet therapy for at least 6 months and the IR for 1 month. The baseline characteristics of both groups were similar. Use of atheroablation devices was less in CR than IR (15.2% vs. 32.8%, respectively; P = 0.001). The overall major adverse cardiac events (death, Q-wave myocardial infarction, and target vessel revascularization; 18.2% vs. 29.1% in IR; P = 0.05) were significantly lower in the CR when compared with patients in the IR. The real-world clinical practice of IRT demonstrates lower events and better clinical outcomes. This is most likely a result of implementation of the lessons learned from the clinical trials such as optimizing the dosimetry by using a higher dose, treating wider margins to minimize edge effect, and administering prolonged antiplatelet therapy to abolish late thrombosis.

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PubMed2005

Internet-based teleangiography: an indispensable tool for the interventional cardiologist.

Efficient and effective communication of specific patient information between referring and consulting physicians has become increasingly important with the need to evaluate a variety of treatment strategies, including coronary bypass surgery, coronary intervention, and medical therapy, without prolonging hospital stay. Until recently, the options available were either slow (mail or courier) or costly and cumbersome (hardware-based digital solutions). eMedcon, a new, easy-to-install Internet-based software solution described in this article, offers a quick and inexpensive solution to image digital cine transfer. eMedcon was tested at our institution, Washington Hospital Center, and was found to transmit images effectively and rapidly between physicians at any Internet-accessible site and Washington Hospital Center. Our data indicate that use of eMedcon led to an increase in repeat referrals and an increase in the number of physicians choosing to refer their patients to our institution.

Coronary Angiography↗

PubMed2005

Underexpansion of sirolimus-eluting stents: incidence and relationship to delivery pressure.

We aimed to assess the incidence of underexpansion and the relationship between delivery pressure and expansion with sirolimus-eluting stents. Adequate stent expansion contributes to early and late improved outcomes. In 51 patients (53 lesions) with native coronary artery narrowing, balloon-expandable sirolimus-eluting stents (Cypher) were serially expanded with gradual balloon inflations [14 atm, 20 atm, and in case of minimal stent cross-sectional area (CSA)/reference lumen CSA < 50% at 20 atm, postdilatation with 0.5 mm larger balloon]. Intravascular ultrasound (IVUS) imaging was performed before intervention and after each gradual balloon inflation. Stent expansion (minimal stent CSA/reference lumen CSA) was measured. Stent expansion was 72% +/- 16% after 14 atm balloon inflation, 90% +/- 18% after 20 atm balloon inflation (P < 0.001 vs. 14 atm), and 90% +/- 18% at the end of the procedure (including optional postdilatations with 0.5 mm larger balloon; P = NS vs. 20 atm). Stent expansion addressed by MUSIC criteria (all struts apposed, no tissue protrusion, and final lumen CSA > 80% of the reference or > 90% if minimal lumen CSA was < 9 mm2) was adequate in 15% of the cases after 14 atm balloon inflation, in 60% after 20 atm balloon inflation (P < 0.001 vs. 14 atm), and in 60% at the end of the procedure (P = NS vs. 20 atm). Sirolimus-eluting stent underexpansion is common when deployed at conventional pressures. Increasing balloon delivery pressure or assessing stent expansion with IVUS seems warranted in order to ensure adequate sirolimus-eluting stent deployment.

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