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Neil J Weissman

Publications and source records attributed to Neil J Weissman.

87 records · Page 5Linked to original sources
PubMed2002

Incidence, morphology, angiographic findings, and outcomes of intramural hematomas after percutaneous coronary interventions: an intravascular ultrasound study.

BACKGROUND: Intramural hematomas during percutaneous coronary intervention (PCI) have not been well studied. METHODS AND RESULTS: We used intravascular ultrasound to determine the incidence, morphology, and clinical features of post-PCI intramural hematomas. In 905 patients with 1025 consecutive native coronary artery, non-in-stent restenosis lesions undergoing PCI, 72 hematomas were detected in 69 arteries in 68 patients. The incidence of intramural hematomas per artery was 6.7% (69 of 1025); 36% (26 of 72) involved the proximal reference artery, 18% (13 of 72) were confined to the lesion, and 46% (33 of 72) involved the distal reference artery. The entry site from the lumen into the hematoma was identified in 86% of hematomas (62 of 72) and had the appearance of a dissection into the media. Conversely, a re-entry site was identifiable in only 8% (6 of 72). The axial extension of the hematoma was distal in 63% and proximal in 37%. In 60% of the hematomas (42 of 72) the angiogram had the appearance of a dissection; in 11% (8 of 72), it appeared to be a new stenosis; and in 29% (22 of 72), no significant abnormality was detected. Non-Q-wave myocardial infarctions occurred in 26% of patients (17 of 65). In 3 patients, the creatine kinase-MB was not measured during the hospital stay. Repeat revascularization occurred in 2 patients in-hospital, 2 additional patients at 1 month, and 8 additional patients at 1 year. There were 3 sudden deaths at 1 year. CONCLUSIONS: Intravascular ultrasound identified intramural hematomas after 6.7% of PCIs. The mechanism appeared to be a dissection into the media where blood accumulated because of a lack of re-entry. A third of ultrasound-identified hematomas showed no angiographic abnormalities. There was a high rate of non-Q-wave myocardial infarction, need for repeat revascularization, and sudden death in patients with hematomas.

Angioplasty, Balloon, Coronary↗
PubMed2002

The impact of obesity on the short-term and long-term outcomes after percutaneous coronary intervention: the obesity paradox?

OBJECTIVES: The purpose of this study was to assess the impact of body mass index (BMI) on the short- and long-term outcomes after percutaneous coronary intervention (PCI). BACKGROUND: Obesity is associated with advanced coronary artery disease (CAD). However, the relation between BMI and outcome after PCI remains controversial. METHODS: We studied 9,633 consecutive patients who underwent PCI between January 1994 and December 1999. Patients were divided into three groups according to BMI: normal, BMI between 18.5 and 24.9 (n = 1,923); overweight, BMI between 25 and 30 (n = 4,813); and obese, BMI >30 (n = 2,897). RESULTS: Obese patients were significantly younger and had consistently worse baseline clinical characteristics than normal or overweight patients, with a higher incidence of hypertension, diabetes, hypercholesterolemia and smoking history (p < 0.0001). Despite similar angiographic success rates among the three groups, normal BMI patients had a higher incidence of major in-hospital complications, including cardiac death (p = 0.001). At one-year follow-up, overall mortality rates were significantly higher for normal BMI patients compared with overweight or obese patients (p < 0.0001). Myocardial infarction and revascularization rates did not differ among the three groups. By multivariate Cox regression analysis, diabetes, hypertension, age, BMI and left ventricular function were independent predictors of long-term mortality. CONCLUSIONS: In patients with known CAD who undergo PCI, very lean patients (BMI <18.5) and those with BMI within the normal range are at the highest risk for in-hospital complications and cardiac death and for increased one-year mortality.

Age Factors↗
PubMed2002

Testing the test: the reliability of echocardiography in the sequential assessment of valvular regurgitation.

BACKGROUND AND OBJECTIVE: Substantial variability in serial echocardiographic qualitative assessment of valvular regurgitation may exist. Reader variability is generally well understood, but acquisition variability (portions of variability caused by equipment, sonographers, physiologic changes) has been less frequently assessed, particularly in combination with reader variability. We attempted to determine the relative contributions of acquisition and reader variability as components of total test-retest variability for aortic (AR) and mitral (MR) regurgitation. METHODS: Outpatient echocardiographic study was done at 2 clinical sites. Twenty-three predominantly obese middle-aged females had 3 echocardiograms, 2 performed 14 +/- 3 days apart and the third performed within 1 to 2 hours of the second. Triplets of echocardiograms were evaluated for change in grade of AR and MR. Medical history, anthropometrics, and blood pressures were obtained. RESULTS: Average intrareader variability (percentage of reads for which there is within-reader disagreement) was 5.6% for AR and 16.7% for MR. The average total test-retest variability (percentage of reads for which there is disagreement between visits) was 29.0% for AR and 24.6% for MR. The acquisition variability for AR was 23.4% +/- 7.7%; for MR, it was 7.9% +/- 10.2%. A significant predictor of change for AR/MR was the initial grade. Change in diastolic blood pressure was positively associated with change in AR and MR. CONCLUSIONS: Intrareader agreement was substantial for AR and MR. Components of total test-retest variability found were reader, biological (change in diastolic blood pressure), and regression to the mean. Recommendations for clinical practice include monitoring blood pressure changes and understanding the confidence limits of the clinical test. Test-retest variability and its components should be considered in echocardiography and other diagnostic testing.

Adolescent↗
PubMed2002

Echocardiographic evaluation of pulmonary artery pressure with clinical correlates in predominantly obese adults.

Pulmonary artery systolic pressure (PASP) was examined in relationship to age, body mass index (BMI), the effects of comorbid disease, and standard echocardiographic measurements of cardiac chamber size, left ventricular filling patterns, and left ventricular systolic function in 5 large cohorts presenting with a primary problem of obesity. For subjects with a measurable PASP, means (+/- SD) across cohorts for age ranged from 46.0 +/- 11.2 to 54.1 +/- 12.8 years, for BMI from 26.0 +/- 4.4 to 37.2 +/- 6.1 kg/m2, and PASP (n = 1515) from 29.9 +/- 7.7 to 33.8 +/- 7.8 mm Hg. PASP 30 mm Hg or greater occurred in 46% to 66% of subjects and 35 mm Hg or greater in 16% to 36%. Age and BMI were the most significant correlates of PASP. Increased PASP was also significantly associated with systemic hypertension and a history of cardiovascular disease. The mean PASP in obese individuals is higher than previously reported with nearly one third having a PASP of 35 mm Hg or greater. Clinical interpretation of PASP should include BMI, age, blood pressure, and presence of cardiovascular disease.

Adult↗
PubMedDate not supplied

Late thrombosis in cypher stents after the discontinuation of antiplatelet therapy.

Drug-eluting stents, since their approval in the United States, have become the treatment of choice for de novo coronary artery narrowing due to their ability to reduce restenosis and the need for repeat revascularization. We present two patients who underwent percutaneous coronary intervention for the treatment of multivessel coronary artery disease; both patients were treated with sirolimus-eluting stents (SES) and bare metal stents (BMS).

Adult↗
PubMedDate not supplied

Comparison of paclitaxel-eluting stent and sirolimus-eluting stent expansion at incremental delivery pressures.

OBJECTIVES: We sought to compare the adequacy of paclitaxel-eluting stent (PES) and sirolimus-eluting stent (SES) expansion based on intravascular ultrasound (IVUS) imaging criteria at conventional delivery pressures. METHODS: Forty-six patients underwent SES implantation and 42 patients underwent PES implantation for de novo native coronary lesions<33 mm in length with reference lumen diameters of 2.5-3.5 mm. Stents were serially expanded with gradual balloon inflations at 14 and 20 atm. IVUS imaging was performed prior to intervention and after each balloon inflation. Stent expansion (minimal stent cross-sectional area/reference lumen cross-sectional area) was measured. Inadequate stent expansion was defined using the MUSIC criteria (all struts apposed, no tissue protrusion, and final lumen cross-sectional area>80% of the reference or >90% if minimal lumen cross-sectional area was <9 mm2). RESULTS: The baseline characteristics of the two groups were similar except for shorter lesion length, larger mean lumen cross-sectional area, larger lumen diameter, and lower plaque burden in the PES group. Stent expansion was inadequate in 80% of patients with SES versus 63% of patients with PES at 14 atm, although this was not statistically significant. After 20 atm, 48% of patients with SES remained underexpanded as compared with 35% of patients with PES. CONCLUSION: Drug-eluting stents showed significant underexpansion by MUSIC criteria at conventionally used inflation pressures. Higher balloon inflations are required especially during deployment of a SES. IVUS guidance is recommended to ensure optimal results and outcomes with both stents.

Aged↗
PubMedDate not supplied

Late thrombosis in drug-eluting coronary stents after discontinuation of antiplatelet therapy.

Although the safety profiles of coronary stents eluting sirolimus or paclitaxel do not seem to differ from those of bare metal stents in the short-to-medium term, concern has arisen about the potential for late stent thromboses related to delayed endothelialisation of the stent struts. We report four cases of angiographically-confirmed stent thrombosis that occurred late after elective implantation of polymer-based paxlitaxel-eluting (343 and 442 days) or sirolimus-eluting (335 and 375 days) stents, and resulted in myocardial infarction. All cases arose soon after antiplatelet therapy was interrupted. If confirmed in systematic long-term follow-up studies, our findings have potentially serious clinical implications.

Aged↗
PubMedDate not supplied

Dose volume histogram assessment of late stent malapposition after intravascular brachytherapy.

PURPOSE: Positive remodeling and decreased neointima proliferation are among the causes for Late Stent Malapposition (LSM). It was our interest to investigate a possible relationship between dose and incidence of LSM. METHODS: Index and follow up IVUS examinations of 238 patients (152 treated with Intravascular Brachytherapy (IVBT), 86 control) enrolled in IVBT trials were reviewed to identify patients with LSM. 7.2% of patients treated with IVBT and 2.3% of patients in the control group were found to have LSM on their 6-month follow-up IVUS. Using the index IVUS study. Dose Volume Histograms (DVH) were constructed for a segment of the adventitia comprising an arc deep to the area where LSM is present at follow up. For control, two areas: an arc deep to complete apposition (Control 1) and a segment within the stent but 5 mm apart from the LSM (Control 2). Volumes were defined by IVUS images that were 1 mm apart and the media-adventitial contour was taken to be 0.5 mm thick from the border. RESULTS: DVH of 90% and 50% adventitial volume of LSM area received a significantly (p < .05) higher dose compared to both controls. Calculated are 12 LSM sites in 9 patients and 9 control sites. At all 12 sites Mean Cross Sectional Area of External Elastic Membrane (EEM CSA) was significantly larger in the LSM group at follow up compared to index (p-.001). CONCLUSIONS: DVH analysis showed a positive correlation between radiation dose to the adventitia and incidence of LSM. The myofibroblasts in the adventitia are known to be the target for irradiation. Proliferation of myofibroblasts leads to neointima formation. LSM may be due to the higher dosages delivered to 50% and 90% of the adventitia volume (LSM area) which may have led to profound neointima suppression. In turn the neointima could not compensate positive remodeling reflected by an increase in EEM CSA.

Blood Vessel Prosthesis Implantation↗