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H Nassar

Publications and source records attributed to H Nassar.

At least 19 recordsLinked to original sources
PubMed2003

Use of ThinPrep monolayer technique and cytospin preparation in urine cytology: a comparative analysis.

We compared the ThinPrep (TP) technique to the cytospin (CS) preparation in the cytological diagnosis of urine by processing 79 specimens by these two techniques. Ten cases were positive for malignancy (six high grade (HG)/carcinoma in situ; four low grade (LG) transitional cell carcinomas (TCC)). Forty-eight cases were within normal limits (59%) and 21 cases had atypical cytological features (19%). The TP technique was better in terms of a cleaner background with fewer obscuring inflammatory cells and blood and with a more even distribution of cells. In general, the cytomorphology was comparable in both techniques. However, in cases with malignancy, CS was relatively superior in the cytomorphologic details; in TP, the diagnostic cells were mostly dispersed as single cells with loss of architectural features and were difficult to find. Artifactual empty spaces and air-drying were more frequently present in TP. In cases contaminated with squamous cells, the urothelial cells were difficult to find in TP. Screening time was comparable for both techniques. In conclusion, to avoid false-negative diagnosis, CS would be complementary to the TP technique in malignant cases and, in particular, those with low cellularity.

Artifacts↗
PubMed2001

Clinicopathologic analysis of invasive micropapillary differentiation in breast carcinoma.

Invasive micropapillary carcinoma (IMPCa) of breast is histologically characterized by growth of cohesive tumor cell clusters within prominent clear spaces resembling dilated angiolymphatic vessels. In this study, eighty three breast carcinomas with IMPCa differentiation were identified by review of the invasive carcinoma cases in our institution and correlated retrospectively with standard clinicopathologic parameters and survival status relative to a control series of cases (mean follow up 7 years). IMPCa growth pattern was present in 6% of all breast carcinomas; it was generally a focal component in otherwise typical invasive ductal carcinoma. It comprised more than 80% of the total neoplasm in only 10 cases (12%), 50-80% of the neoplasm in 7 cases (8%), 20-50% of the neoplasm in 22 cases (26%) and less than 20% in 44 cases (53%). The mean tumor size was 4 cm, 22% invaded skin, and 58% were poorly differentiated, but 71% were ER positive. Axillary node metastases were present in 77% of cases, were typically multiple (51% had three or more positive), and usually contained an IMPCa component (81% of the cases). There was no significant difference in node status, ER status, size, tumor grade, or peritumoral angiolymphatic invasion between tumors with predominant (more than 50%) v/s focal IMPCa components. In both groups 46% of the patients died from their disease (mean interval to death = 36m). Skin involvement and nodal status were the only parameters which predicted poor survival (P =.01). The outcome of patients with IMPCa did not differ significantly from infiltrating ductal carcinomas of similar node status. In conclusion, our results suggest that IMPCa growth pattern may be a manifestation of aggressive behavior, as shown by frequent skin invasion and extensive nodal involvement. However, clinicopathologic features and outcome of IMPCa are not strongly dependent on the relative amount of micropapillary component.

Aged↗
PubMed1999

Long-term outcome of patients with very long stents for treatment of diffuse coronary disease.

OBJECTIVES: The study sought to determine the 6-month clinical outcome of patients who underwent implantation of very long coronary stents to treat diffuse disease and/or long dissections and to compare the findings with those reported in the literature for patients who underwent implantation of multiple short coronary stents. BACKGROUND: New designs of flexible stents enable the implantation of long stents rather than multiple short, older design stents. The initial experience is very promising but the long-term outcome has not been described yet. METHODS: Fifty-seven consecutive patients in whom 67 long stents (>/=30 mm) were successfully deployed were included in this study. Six-month clinical and angiographic follow-up was prospectively collected. Patients with recurrent angina underwent coronary angiography without further testing. Patients who remained asymptomatic at the 6-month follow-up visit underwent positron emission tomographic imaging, and those with results suggestive of ischemia underwent coronary angiography. A combined study end point was defined as death, myocardial infarction, and the need for target vessel revascularization. RESULTS: Only 1 patient (2%) reached a study end point at hospital discharge. An additional 20 patients (total 21 patients [37%]) reached an end point by 6 months. The outcome was not influenced by the clinical presentation (stable or unstable angina) or by the indication for stenting (elective or emergency). Predictors for adverse outcome were multiple stents per narrowing (63% vs 29%, P <. 04), and stents smaller than 3.5 mm (49% vs 22%). Narrowing and stent length were not predictive of a study end point in narrowings that were successfully treated by a single long stent. CONCLUSIONS: Elective stenting provides an effective solution for patients with diffuse coronary disease provided that a single long stent (usually <40 mm) can cover the full length of the narrowing. The results are better when vessels larger than 3 mm are treated. Compared with multiple short stents, implantation of a single long stent is probably at least as effective, and the procedure is quicker and cheaper and thus should be the preferred approach.

Aged↗
PubMed1999

The Cutting Balloon--a new technology?

The Cutting Balloon consists of a standard balloon dilatation catheter with four microtome-sharp blades that incise the plaque and minimize arterial wall trauma. It was used in 31 patients; nine had calcified arteries, ten had non-compliant lesions, three had in-stent restenosis and nine had aorto-ostial lesions. Seventeen lesions were predilated, 28 were post-dilated and 18 required stent implantation. The procedure was very effective in aorto-ostial lesions, non-compliant lesions that were not responsive to high-pressure balloon dilatation, and was partially successful in calcified arteries. It has a very specific niche in selected lesions.

Journal Article↗
PubMed1999

Effects of the superoxide dismutase-mimic compound TEMPOL on oxidant stress-mediated endothelial dysfunction.

The aim of this study was to investigate the effects of oxidant stress on endothelium-dependent and endothelium-independent arterial relaxation. For this, oxidant stress was generated by preincubation of rat aortic rings (RARs) in either 25 mM glucose (mimicking hyperglycemic stress) or 0.5 mM pyrogallol (a superoxide generator) and the effects of the superoxide dismutase (SOD)-mimetic compound 4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy free radical (TEMPOL) on the vasorelaxant and cGMP-producing effects of acetylcholine (ACh) and glyceryl trinitrate (GTN) in control RARs and RARs exposed to oxidant stress were examined. Pyrogallol, and to a lesser extent high glucose concentration, enhanced the contractile response of RARs to phenylephrine and markedly inhibited the vasorelaxant response to ACh. Although they existed, the inhibitory effects of high glucose and pyrogallol on the vasorelaxant response to GTN were less profound, especially with pyrogallol. Moreover, both pyrogallol and high glucose concentration inhibited the basal and the ACh-induced vascular cyclic guanosine monophosphate (cGMP) production. Treatment with TEMPOL (1-5 mM) slightly increased the ACh and GTN-induced cGMP levels in control RARs but had a significant effect in high glucose and pyrogallol-pretreated RARs. Additionally, concomitant treatment of RARs with TEMPOL (5 mM) abolished the difference in the relaxation response between control RARs and RARs exposed to either pyrogallol or high glucose concentration. These results further support the theory that reactive oxygen species (ROS), especially superoxide, play a key role in mediation of endothelial dysfunction accompanying diabetes, probably through their effects on the ability of the endothelium to synthesize, release or respond to endogenous nitric oxide (NO) or NO donated by nitrovasodilators.

Acetylcholine↗
PubMed1998

[Percutaneous revascularization of the left main coronary artery as coronary artery bypass in high surgical risks].

Coronary artery bypass grafting is the treatment of choice for obstructive disease of the left main coronary artery. Its proximal location and easy accessibility make the left main artery an inviting target for percutaneous intervention, an approach contraindicated by the high associated risk. We describe 2 patients at high operative risk in whom the obstructed main coronary artery was successfully revascularized percutaneously. Coronary stenting and rotational ablation of calcified arteries are essential for successful outcome and minimize complications.

Aged↗
PubMed1997

Long-term angiographic follow-up of coronary balloon angioplasty in patients with diabetes mellitus: a clue to the explanation of the results of the BARI study. Balloon Angioplasty Revascularization Investigation.

OBJECTIVES: We sought to compare the angiographic outcome of diabetic patients (treated with insulin or oral hypoglycemic agents) after successful coronary angioplasty with that in nondiabetic patients. The analysis included the outcome of the dilated (restenosis) and nondilated narrowings (disease progression). BACKGROUND: Recent data have confirmed that diabetes mellitus is an important risk factor for long-term adverse events. These adverse events are more common after balloon angioplasty than after bypass surgery (Bypass Angioplasty Revascularization Investigation [BARI]). METHODS: We examined retrospectively 353 coronary angiograms of 248 patients (55 diabetic, 193 nondiabetic) who were referred for diagnostic angiography >1 month after successful angioplasty (1.4 +/- 0.6 [mean +/- SD] repeat angiograms/patient). Restenosis and disease progression/regression were compared between groups by means of quantitative angiography. RESULTS: Baseline clinical and angiographic characteristics were similar in both groups. There was a nonsignificant trend for a higher restenosis rate of dilated narrowings in diabetic patients. There were no significant changes between diabetic and nondiabetic patients in the rates of progression and regression of narrowings that were not dilated during the initial angioplasty. The main difference was in the rate of appearance of new narrowings: There was a 22% increase in the number of narrowings on the follow-up angiogram in diabetic patients (38 new, 174 preexisting narrowings) compared with 12% (86 new, 734 preexisting narrowings) in nondiabetic patients (p < 0.004). Diabetes mellitus and the performance of angioplasty in the artery had an additive risk for development of new narrowings, which were identified in 15 (16.9%) of 89 arteries with and 16 (13.2%) of 121 without angioplasty in diabetic patients and in 42 (12.7%) of 331 arteries with and 38 (7.3%) of 518 without angioplasty in nondiabetic patients (p = 0.009). CONCLUSIONS: The combination of diabetes mellitus and an artery that was instrumented during balloon angioplasty is additive and increases the risk of formation of new narrowing in that artery. This finding may explain the high adverse event rates observed in diabetic patients in the angioplasty arm of the BARI study, most of whom had angioplasty performed in at least two arteries.

Aged↗
PubMed1997

Atherosclerosis studies by intracoronary ultrasound.

Intravascular ultrasound (IVUS) is a new technique of tomographic visualization of the coronary arteries: its lumen, wall and pathology. Three dimensional (3D) reconstruction shows the tubular structure of the arterial wall and its pathology. IVUS has many advantages over coronary angiography: it has better resolution and shows many hidden lesions. IVUS has helped uncover the underlying mechanisms of percutaneous transluminal coronary angioplasty (PTCA), restenosis, the use and value of other interventional techniques such as directional coronary atherectomy (DCA), rotational atherectomy and stent implantation, and has great value in planning complex interventional procedures. The new American Heart Association (AHA) classification of coronary atherosclerosis pathology can be demonstrated by IVUS. IVUS is sensitive for studies of atheroma regression and progression and shows the coronary artery lesions after cardiac transplantation.

Animals↗
PubMed1997

Initial experience with long coronary stents: the changing practice of coronary angioplasty.

The initial experience with the use of long coronary stents (> 30 mm in length) was analyzed retrospectively. Sixty-seven stents were deployed in 58 narrowings in 57 patients (34 AVE Microstents, 16 Nir stents, four Gianturco-Roubin II stents, and 13 Wallstents). Stents were implanted in 22 patients with unstable angina, 34 patients with stable angina, and one patient during direct angioplasty for acute myocardial infarction. Eighteen additional short stents were implanted to cover the entire length of the lesions so that an average of one and a half stents were deployed per patient. The length of the narrowings before stenting was 40 +/- 20 mm and the length of the stented segments was 45 +/- 20 mm. Stents were deployed for "bailout" in 23 narrowings, to improve suboptimal results of balloon angioplasty in 18 narrowings, and electively in 17 narrowings. Twenty of the 67 long stents were deployed in saphenous vein grafts. The success rate of stent implantation was 100%. One patient had a rupture of a saphenous vein graft after deployment of two long stents, with tamponade treated by emergency surgery. One patient had chest pain 18 hours after stent deployment; by the time he arrived at the catheterization laboratory the pain had subsided and the angiogram revealed a patent artery with normal flow. There were no other major complications during the hospital course and 1-month follow-up. We conclude that long coronary stents can be deployed successfully in native coronary arteries and vein grafts. They are useful for elective implantation and extremely helpful in bailout situations. The immediate results are excellent, but long-term outcome is awaited.

Aged↗
PubMed1997

The Radial Artery: An Applicable Approach to Complex Coronary Angioplasty.

The purpose of this study was to assess the clinical value of the transradial approach (TRA) in coronary angioplasty. During the 18Ðmonth period from June 1994 to December 1995, 250 patients (mean age 61 +/- 11) underwent coronary angioplasty using the transradial approach. In 7 (2.8%) radial puncture was unsuccessful and in 6 (2.4%) additional femoral access was needed to complete the procedure. Ninety patients (36%) had angioplasty of two or three vessels and 49.5% had type B2 or C lesions. Sixty-five patients (22%) had additional procedures: stent implantations in 50 (16%) and rotational ablation in 15 (6%). Angiographic success was 97% and there were no deaths. Major procedural complications included: Q-wave myocardial infarction in 2 (0.8%), non-Q-wave myocardial infarction in 5 (2.0%), urgent coronary artery bypass grafting in 2 (0.8%) and CVA in 2 (0.8%). Local vascular complication included: compartment syndrome necessitating fasciotomy in 1 patient (0.4%), mild hematoma in 6 (2.4%) and a small pseudo-aneurysm treated by local compression in 4 (1.6%). Radial pulse was palpated in 93% before discharge and in 3% adequate flow could be heard with Doppler. No patient suffered from ischemia of the hand. Complex coronary angioplasty can be performed safely using the TRA with few vascular complications.

Journal Article↗
PubMed1996

Experience with the AVE Micro stent in native coronary arteries.

Experience with implantation of 62 AVE Micro stents is described. Stents were quickly and successfully deployed in 62 of 63 attempts (98.4%), in tortuous coronary vessels, through proximally deployed stents, and under conditions of hemodynamic instability. It is therefore a very attractive choice to treat difficult anatomy during urgent situations.

Aged↗
PubMed1996

Microvascular soft-tissue coverage and distraction osteosynthesis for lower-extremity salvage.

In our attempts to salvage massive lower-extremity injuries, even in the presence of severe peripheral vascular pathology, adequate soft-tissue coverage is no longer a limiting factor due to recent advances in microvascular composite tissue transfer. Restoration of tibial continuity without shortening has emerged as the last obstacle in the formidable task of salvaging lower extremities with grade III B and III C defects. Proposed solutions to this problem include conventional free cancellous bone-grafting applicable to small defects only, vascularized bone grafts, or shortening of the leg with subsequent elongation using the Ilizarov technique. We present our experience with 3 consecutive cases of lower-limb salvage, utilizing a new approach in which microsurgical soft-tissue reconstruction has been combined with bony reconstruction by distraction osteosynthesis. Bone transport by distraction osteosynthesis under a free flap performed while preserving the initial limb length throughout the treatment period proved to be superior to other methods in selected cases and is presented as a new technique for the management of problematic lower-limb injuries.

Adolescent↗
PubMed1995

Transradial approach for coronary angiography and angioplasty.

The transradial approach has currently been advocated as an alternative catheterization method for coronary angiography and angioplasty, due to the recent miniaturization of angioplasty equipment. The purpose of this study was to assess the practical clinical applicability of this method. From June to November 1994, 100 patients underwent coronary angiography and angioplasty with the transradial approach. Their mean age was 66.6 +/- 11.2 years, and 79 were men. In 4, radial puncture was not successful, and in 3, femoral access was necessary to complete the procedure. Coronary angioplasty was performed in 63 patients (76 lesions) with angiographic success (per lesion) of 96%. In 5 patients, a stent was successfully implanted. All patients were ambulatory on the day after the angioplasty procedure. In 98% of the patients, the introducer was taken out 1 to 4 hours after the procedure by local compression using a special custom-made device. No patient required blood transfusion. Major complications occurred in 2 patients; both had a cerebrovascular accident (1 probably not procedure-related), and both recovered. A radial pulse was palpated in 91 of the patients before discharge, and in 6 others, adequate flow could be heard with Doppler. In 2 patients, radial flow was restored within several weeks. None of the patients suffered from ischemia of the hand. Two patients had a small pseudoaneurysm successfully treated by local compression. Thus, coronary angioplasty can be performed safely using the transradial approach with relatively few vascular complications and with better patient comfort. However, the procedure is more time-consuming initially compared with the transfemoral approach due to a learning curve regarding equipment selection and catheter manipulation.

Adult↗
PubMed1995

Acute myocardial infarction--the angiographic picture: new insights into the pathogenesis of myocardial infarction.

The angiographic appearance of the coronary arteries were examined in 302 patients with stable angina pectoris and compared to 308 patients with acute myocardial infarction, who received high-dose intravenous thrombolytic therapy, in order to elucidate the underlying angiopathological picture in the two diseases. In each group coronary lesions were present in proximal segments of the arteries and were closely related to bifurcations. Lesions were more extensively distributed in the coronary tree in patients with stable angina and they had an average of 5.4 lesions per patient, compared to the acute myocardial infarction group who had only 2.4 lesions. Also, in the acute myocardial infarction patients, four-fifths of the culprit arteries were patent, 104 (34%) had a ruptured plaque, 22 (7%) had an ulcerated plaque and in 190 (62%) the lesions were eccentric. The study shows that patients with myocardial infarction who are suitable for thrombolysis have a unique coronary angiographic picture and the acute episode is caused by sudden rupture of a localized atheromatous plaque which initiates an obstructive thrombotic cascade.

Angina Pectoris↗
PubMed1995

Dissecting aortic aneurysm in systemic lupus erythematosus.

Many cardiovascular manifestations have been described in systemic lupus erythematosus (SLE). Aortic involvement, however, is very rare. We describe a 30-year-old woman with SLE who presented with extensive aortic dissection, and review the few reported cases. We discuss possible pathogenic mechanisms for aortic involvement in lupus and the appropriate diagnostic work-up.

Adult↗